201
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Search for three-jet resonances in pp collisions at square root(s)=7 TeV. PHYSICAL REVIEW LETTERS 2011; 107:101801. [PMID: 21981492 DOI: 10.1103/physrevlett.107.101801] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/16/2011] [Indexed: 05/31/2023]
Abstract
A search for three-jet hadronic resonance production in pp collisions at a center-of-mass energy of 7 TeV has been conducted by the CMS Collaboration at the LHC, using a data sample corresponding to an integrated luminosity of 35 pb(-1). Events with high jet multiplicity and a large scalar sum of jet transverse momenta are analyzed using a signature-based approach. The number of expected standard model background events is found to be in good agreement with the observed events. Limits on the cross section times branching ratio are set in a model of gluino pair production with an R-parity-violating decay to three quarks, and the data rule out such particles within the mass range of 200 to 280 GeV/c2.
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202
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Measurement of the t-channel single top quark production cross section in pp collisions at √s=7 TeV. PHYSICAL REVIEW LETTERS 2011; 107:091802. [PMID: 21929225 DOI: 10.1103/physrevlett.107.091802] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/16/2011] [Indexed: 05/31/2023]
Abstract
Electroweak production of the top quark is measured for the first time in pp collisions at √=7 TeV, using a data set collected with the CMS detector at the LHC and corresponding to an integrated luminosity of 36 pb⁻¹. With an event selection optimized for t-channel production, two complementary analyses are performed. The first one exploits the special angular properties of the signal, together with background estimates from the data. The second approach uses a multivariate analysis technique to probe the compatibility with signal topology expected from electroweak top-quark production. The combined measurement of the cross section is 83.6±29.8(stat+syst)±3.3(lumi) pb, consistent with the standard model expectation.
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203
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Indications of suppression of excited Υ states in Pb-Pb collisions at √(s(NN))=2.76 TeV. PHYSICAL REVIEW LETTERS 2011; 107:052302. [PMID: 21867063 DOI: 10.1103/physrevlett.107.052302] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/25/2011] [Indexed: 05/31/2023]
Abstract
A comparison of the relative yields of Υ resonances in the μ(+)μ(-) decay channel in Pb-Pb and pp collisions at a center-of-mass energy per nucleon pair of 2.76 TeV is performed with data collected with the CMS detector at the LHC. Using muons of transverse momentum above 4 GeV/c and pseudorapidity below 2.4, the double ratio of the Υ(2S) and Υ(3S) excited states to the Υ(1S) ground state in Pb-Pb and pp collisions, [Υ(2S+3S)/Υ(1S)](Pb-Pb)/[Υ(2S+3S)/Υ(1S)](pp), is found to be 0.31(-0.15)(+0.19)(stat)±0.03(syst). The probability to obtain the measured value, or lower, if the true double ratio is unity, is calculated to be less than 1%.
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204
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Measurement of the polarization of W bosons with large transverse momenta in W + jets events at the LHC. PHYSICAL REVIEW LETTERS 2011; 107:021802. [PMID: 21797595 DOI: 10.1103/physrevlett.107.021802] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/21/2011] [Indexed: 05/31/2023]
Abstract
A first measurement of the polarization of W bosons with large transverse momenta in pp collisions is presented. The measurement is based on 36 pb⁻¹ of data recorded at √s = 7 TeV by the CMS detector at the LHC. The left-handed, right-handed, and longitudinal polarization fractions (f(L), f(R), and f₀, respectively) of W bosons with transverse momenta larger than 50 GeV are determined by using decays to both electrons and muons. The muon final state yields the most precise measurement: (f(L) - f(R))⁻ = 0.240 ± 0.036(stat) ± 0.031(syst) and f₀⁻ = 0.183 ± 0.087(stat) ± 0.123(syst) for negatively charged W bosons and (f(L) - f(R))⁺ = 0.310 ± 0.036(stat) ± 0.017(syst) and f₀⁺ = 0.171 ± 0.085(stat) ± 0.099(syst) for positively charged W bosons. This establishes, for the first time, that W bosons produced in pp collisions with large transverse momenta are predominantly left-handed, as expected in the standard model.
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Abstract
Anion transport drives fluid into the airways and is essential for humidifying inspired air and supplying surface liquid for mucociliary transport. Despite the importance of airway secretion in diseases such as cystic fibrosis, the cellular mechanisms remain poorly understood, in part due to the small size and complicated structure of the submucosal glands that produce most of the fluid. The Calu-3 human lung adenocarcinoma cell line has become a popular model for studying airway secretion because it can be cultured as a flat sheet, expresses the cystic fibrosis transmembrane conductance regulator and several acinar cell markers, forms polarized monolayers with tight junctions, has robust cAMP-stimulated anion transport, and responds to secretagogues that regulate the glands in vivo. However, some properties of Calu-3 cells are less consistent with those of native tissue. In particular, Calu-3 monolayers do not secrete chloride when stimulated by forskolin under short-circuit conditions. Bicarbonate ions are thought to carry the short-circuit current (I(sc)) and the drive secretion of alkaline fluid, in contrast to the neutral pH secretions that are produced by submucosal glands. Calu-3 cells also have abnormal chromosomes and characteristics of both serous and mucus cells. In this article, we discuss Calu-3 as a model in light of our ongoing studies, which suggest that Calu-3 monolayers resemble submucosal glands more closely than was previously thought. For example, we find that net HCO(3)(-) flux fully accounts for I(sc) as previously suggested but Cl(-) is the main anion transported under physiological conditions. A novel, HCO(3)(-) -dependent mechanism of Cl(-) transport is emerging which may explain secretion by Calu-3 and perhaps other epithelial cells.
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206
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Measurement of the B0 production cross section in pp collisions at sqrt[s] = 7 TeV. PHYSICAL REVIEW LETTERS 2011; 106:252001. [PMID: 21770632 DOI: 10.1103/physrevlett.106.252001] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/14/2011] [Indexed: 05/31/2023]
Abstract
Measurements of the differential production cross sections dσ/dpTB and dσ/dyB for B0 mesons produced in pp collisions at sqrt[s] = 7 TeV are presented. The data set used was collected by the CMS experiment at the LHC and corresponds to an integrated luminosity of 40 pb-1. The production cross section is measured from B0 meson decays reconstructed in the exclusive final state J/ψKS0, with the subsequent decays J/ψ → μ + μ - and KS0 → π+}π-. The total cross section for pTB>5 GeV and |yB|<2.2 is measured to be 33.2 ± 2.5 ± 3.5 μb, where the first uncertainty is statistical and the second is systematic.
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207
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Search for neutral minimal supersymmetric standard model Higgs bosons decaying to tau pairs in pp collisions at √s=7 TeV. PHYSICAL REVIEW LETTERS 2011; 106:231801. [PMID: 21770497 DOI: 10.1103/physrevlett.106.231801] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/09/2011] [Indexed: 05/31/2023]
Abstract
A search for neutral minimal supersymmetric standard model (MSSM) Higgs bosons in pp collisions at the LHC at a center-of-mass energy of 7 TeV is presented. The results are based on a data sample corresponding to an integrated luminosity of 36 pb(-1) recorded by the CMS experiment. The search uses decays of the Higgs bosons to tau pairs. No excess is observed in the tau-pair invariant-mass spectrum. The resulting upper limits on the Higgs boson production cross section times branching fraction to tau pairs, as a function of the pseudoscalar Higgs boson mass, yield stringent new bounds in the MSSM parameter space.
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208
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Search for supersymmetry in pp collisions at √7 TeV in events with two photons and missing transverse energy. PHYSICAL REVIEW LETTERS 2011; 106:211802. [PMID: 21699288 DOI: 10.1103/physrevlett.106.211802] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/04/2011] [Indexed: 05/31/2023]
Abstract
A search for supersymmetry in the context of general gauge-mediated breaking with the lightest neutralino as the next-to-lightest supersymmetric particle and the gravitino as the lightest is presented. The data sample corresponds to an integrated luminosity of 36 pb(-1) recorded by the CMS experiment at the LHC. The search is performed by using events containing two or more isolated photons, at least one hadronic jet, and significant missing transverse energy. No excess of events at high missing transverse energy is observed. Upper limits on the signal cross section for general gauge-mediated supersymmetry between 0.3 and 1.1 pb at the 95% confidence level are determined for a range of squark, gluino, and neutralino masses, excluding supersymmetry parameter space that was inaccessible to previous experiments.
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209
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Study of Z Boson Production in PbPb Collisions at √S(NN)=2.76 TeV. PHYSICAL REVIEW LETTERS 2011; 106:212301. [PMID: 21699291 DOI: 10.1103/physrevlett.106.212301] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/01/2011] [Indexed: 05/31/2023]
Abstract
A search for Z bosons in the μ(+)μ(-) decay channel has been performed in PbPb collisions at √S(NN)=2.76 TeV with the CMS detector at the LHC, in a 7.2 μb(-1) data sample. The number of opposite-sign muon pairs observed in the 60-120 GeV/c(2) invariant mass range is 39, corresponding to a yield per unit of rapidity (y) and per minimum bias event of [33.8±5.5(stat)±4.4(syst)]×10(-8), in the |y|<2.0 range. Rapidity, transverse momentum, and centrality dependencies are also measured. The results agree with next-to-leading order QCD calculations, scaled by the number of incoherent nucleon-nucleon collisions.
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210
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Measurement of dijet angular distributions and search for quark compositeness in pp collisions at √s = 7 TeV. PHYSICAL REVIEW LETTERS 2011; 106:201804. [PMID: 21668222 DOI: 10.1103/physrevlett.106.201804] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/10/2011] [Indexed: 05/30/2023]
Abstract
Dijet angular distributions are measured over a wide range of dijet invariant masses in pp collisions at √s = 7 TeV, at the CERN LHC. The event sample, recorded with the CMS detector, corresponds to an integrated luminosity of 36 pb⁻¹. The data are found to be in good agreement with the predictions of perturbative QCD, and yield no evidence of quark compositeness. With a modified frequentist approach, a lower limit on the contact interaction scale for left-handed quarks of Λ⁺ = 5.6 TeV (Λ⁻ = 6.7 TeV) for destructive (constructive) interference is obtained at the 95% confidence level.
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211
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Effect of omega-3 fatty acids alone and in combination with raloxifene on biomarkers of breast cancer risk in postmenopausal healthy women at high risk. J Clin Oncol 2011. [DOI: 10.1200/jco.2011.29.15_suppl.e11036] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
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212
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Search for pair production of second-generation scalar leptoquarks in pp collisions at √s = 7 TeV. PHYSICAL REVIEW LETTERS 2011; 106:201803. [PMID: 21668221 DOI: 10.1103/physrevlett.106.201803] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/17/2010] [Indexed: 05/30/2023]
Abstract
A search for pair production of second-generation scalar leptoquarks in the final state with two muons and two jets is performed using proton-proton collision data at √s = 7 TeV collected by the CMS detector at the LHC. The data sample used corresponds to an integrated luminosity of 34 pb⁻¹. The number of observed events is in good agreement with the predictions from the standard model processes. An upper limit is set on the second-generation leptoquark cross section times β² as a function of the leptoquark mass, and leptoquarks with masses below 394 GeV are excluded at a 95% confidence level for β = 1, where β is the leptoquark branching fraction into a muon and a quark. These limits are the most stringent to date.
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213
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Search for pair production of first-generation scalar leptoquarks in pp collisions at √s = 7 TeV. PHYSICAL REVIEW LETTERS 2011; 106:201802. [PMID: 21668220 DOI: 10.1103/physrevlett.106.201802] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/17/2010] [Indexed: 05/30/2023]
Abstract
A search for pair production of first-generation scalar leptoquarks is performed in the final state containing two electrons and two jets using proton-proton collision data at √s = 7 TeV. The data sample used corresponds to an integrated luminosity of 33 pb⁻¹ collected with the CMS detector at the CERN LHC. The number of observed events is in good agreement with the predictions for the standard model background processes, and an upper limit is set on the leptoquark pair production cross section times β² as a function of the leptoquark mass, where β is the branching fraction of the leptoquark decay to an electron and a quark. A 95% confidence level lower limit is set on the mass of a first-generation scalar leptoquark at 384 GeV for β = 1, which is the most stringent direct limit to date.
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214
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Wardrobe. CMAJ 2011. [DOI: 10.1503/cmaj.100857] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022] Open
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215
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Dijet azimuthal decorrelations in pp collisions at √s=7 TeV. PHYSICAL REVIEW LETTERS 2011; 106:122003. [PMID: 21517306 DOI: 10.1103/physrevlett.106.122003] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/26/2011] [Indexed: 05/30/2023]
Abstract
Measurements of dijet azimuthal decorrelations in pp collisions at √s=7 TeV using the CMS detector at the CERN LHC are presented. The analysis is based on an inclusive dijet event sample corresponding to an integrated luminosity of 2.9 pb⁻¹. The results are compared to predictions from perturbative QCD calculations and various Monte Carlo event generators. The dijet azimuthal distributions are found to be sensitive to initial-state gluon radiation.
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216
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Measurement of the B(+) production cross section in pp collisions at sqrt[s]=7 TeV. PHYSICAL REVIEW LETTERS 2011; 106:112001. [PMID: 21469857 DOI: 10.1103/physrevlett.106.112001] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/31/2010] [Indexed: 05/30/2023]
Abstract
Measurements of the total and differential cross sections dσ/dp(T)(B) and dσ/dy(B) for B(+) mesons produced in pp collisions at sqrt[s]=7 TeV are presented. The data correspond to an integrated luminosity of 5.8 pb(-1) collected by the CMS experiment operating at the LHC. The exclusive decay B(+)→J/ψK(+), with J/ψ→μ(+)μ(-), is used to detect B(+) mesons and to measure the production cross section as a function of p(T)(B) and y(B). The total cross section for p(T)(B)>5 GeV and |y(B)|<2.4 is measured to be 28.1±2.4±2.0±3.1 μb, where the first uncertainty is statistical, the second is systematic, and the last is from the luminosity measurement.
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217
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Measurement of the isolated prompt photon production cross section in pp collisions at √s=7 TeV. PHYSICAL REVIEW LETTERS 2011; 106:082001. [PMID: 21405566 DOI: 10.1103/physrevlett.106.082001] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/03/2010] [Revised: 01/15/2011] [Indexed: 05/30/2023]
Abstract
The differential cross section for the inclusive production of isolated prompt photons has been measured as a function of the photon transverse energy E(T)(γ) in pp collisions at √s=7 TeV using data recorded by the CMS detector at the LHC. The data sample corresponds to an integrated luminosity of 2.9 pb(-1). Photons are required to have a pseudorapidity |η(γ)|<1.45 and E(T)(γ)>21 GeV, covering the kinematic region 0.006<x(T)<0.086. The measured cross section is found to be in agreement with next-to-leading-order perturbative QCD calculations.
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218
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Effect of a novel FAK inhibitor targeted to the binding site of VEGFR3 on pancreatic cancer proliferation in vitro and in vivo. J Clin Oncol 2011. [DOI: 10.1200/jco.2011.29.4_suppl.214] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
214 Background: Even with successful surgical resection and treatment pancreatic adenocarcinoma has a high incidence of recurrence because of metastatic spread. Vascular endothelial growth factor receptor 3 (VEGFR3) is related to lymphatic metastasis. VEGFR3 binds to the survival protein, focal adhesion kinase (FAK), to promote pancreatic cancer (PC) lymphangiogenesis. In this study we have pinpointed the site of interaction of VEGFR3 and FAK to create drug capable of disrupting their signaling with antitumor effect. Methods: 200,000 small molecules were screened in silico for their abilities to interact with the VEGFR3 /FAK binding site. Effects of the selected compounds on PC cell lines MiaPaCa2 and Panc1 were examined by MTT assay (viability), BrdU incorporation (proliferation), Boyden chamber (motility), TUNEL and flow cytometry (cell cycle, apoptosis), and Western blot (phosphorylation, apoptosis). Results: We selected compound C4 because it disrupted the FAK-VEGFR3 complexes in PC cells, as was shown by immunoprecipitation. It caused a dose-dependent dephosphorylation and inactivation of the VEGFR3. Inhibition of VEGFR3 with 10μM of C4 resulted in 80% reduction in cell viability, decrease in proliferation and a 50% reduction in motility. Treatment led to apoptosis in PC cells, confirmed by PARP cleavage. C4 increased the sensitivity of PC cells to chemotherapy in vitro. MiaPaca2 have shown 40% apoptosis after only 24 h of treatment with combination of C4 and gemcitabine at nanomolar concentrations ineffective alone. C4 reduced tumor growth in vivo in murine models of PC. C4 (60 mg/kg, daily IP) decreased tumor growth after 21 days of treatment to 60% (P=0.017). Lower dose of the C4 (10 mg/kg) still had an effect and inhibited tumor growth by 30%, but concomitant administration with low dose of gemcitabine (4 mg/kg, Q4dx6), had significant synergistic effect and led to 80% of tumor reduction. We also have shown that combination of C4 with gemcitabine had prolonged cytostatic effect on tumor growth after treatment withdrawal. Conclusions: Targeting the scaffolding function of FAK with the small-molecule inhibitors can be effectively used to develop potential oral-based PC therapeutics. [Table: see text]
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219
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Search for stopped Gluinos in pp collisions at square root s=7 TeV. PHYSICAL REVIEW LETTERS 2011; 106:011801. [PMID: 21231732 DOI: 10.1103/physrevlett.106.011801] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/26/2010] [Indexed: 05/30/2023]
Abstract
The results of the first search for long-lived gluinos produced in 7 TeV pp collisions at the CERN Large Hadron Collider are presented. The search looks for evidence of long-lived particles that stop in the CMS detector and decay in the quiescent periods between beam crossings. In a dataset with a peak instantaneous luminosity of 1×10(32) cm-2 s-1, an integrated luminosity of 10 pb-1, and a search interval corresponding to 62 hours of LHC operation, no significant excess above background was observed. Limits at the 95% confidence level on gluino pair production over 13 orders of magnitude of gluino lifetime are set. For a mass difference mg - mχ1(0) >100 GeV/c2, and assuming BR(g→gχ1(0))=100%, mg < 370 GeV/c2 are excluded for lifetimes from 10 μs to 1000 s.
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220
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A comparison of Arctic BrO measurements by chemical ionization mass spectrometry and long path-differential optical absorption spectroscopy. ACTA ACUST UNITED AC 2011. [DOI: 10.1029/2010jd014788] [Citation(s) in RCA: 89] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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221
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222
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Association of single-nucleotide polymorphisms in HLA class II/III region with knee osteoarthritis. Osteoarthritis Cartilage 2010; 18:1454-7. [PMID: 20691797 DOI: 10.1016/j.joca.2010.07.009] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/08/2010] [Revised: 07/18/2010] [Accepted: 07/20/2010] [Indexed: 02/02/2023]
Abstract
OBJECTIVE A genome-wide association study and a replication using Japanese, Spanish and Greek Caucasian populations have recently indicated two single-nucleotide polymorphisms (SNPs) (rs7775228 and rs10947262) associated with knee Osteoarthritis (OA) susceptibility. We have further evaluated the association in knee OA subjects from Han Chinese and Australian Caucasian origin. METHODS Two independent case-control association studies were performed using Han Chinese and Australian Caucasian populations. The two SNPs were genotyped in patients who had primary symptomatic knee OA with radiographic confirmation and/or received total knee replacement surgery as well as in matched controls. They were subjected to statistic analyses. RESULTS A total of 991 OA patients and 1536 controls were genotyped. No significant difference was detected in genotype or allele frequencies of the two SNPs between knee OA and control groups in the two populations (all P>0.05). The association was also negative even after stratification by sex, body mass index (BMI) and Kellgren/Lawrence scores. The significant heterogeneity was detected between Chinese and Japanese (both P<0.05). In the Caucasian samples, no significant heterogeneity was detected (both P>0.05). The result of meta-analysis showed significant association between knee OA and rs10947262 in total subjects [summary OR=1.26, 95%confidence intervals (CI)=1.07-1.27, P=3 × 10(-8)] and in Caucasian samples (summary OR=1.28, 95%CI=1.04-1.57, P=0.02). CONCLUSION We demonstrated no association between the two SNPs in human leukocyte antigen (HLA) class II/III region and knee OA in Han Chinese population. A significant association was detected between SNP rs10947262 and knee OA in Caucasian subjects. Further replication studies are required to identify the impact of controversial association.
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223
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Effects of TGF-beta3 and preculture period of osteogenic cells on the chondrogenic differentiation of rabbit marrow mesenchymal stem cells encapsulated in a bilayered hydrogel composite. Acta Biomater 2010; 6:2920-31. [PMID: 20197126 DOI: 10.1016/j.actbio.2010.02.046] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2009] [Revised: 02/23/2010] [Accepted: 02/24/2010] [Indexed: 12/17/2022]
Abstract
In this work, injectable, biodegradable hydrogel composites of crosslinked oligo(poly(ethylene glycol) fumarate) and gelatin microparticles (MPs) were used to fabricate a bilayered osteochondral construct. Rabbit marrow mesenchymal stem cells (MSCs) were encapsulated with transforming growth factor-beta3 (TGF-beta3)-loaded MPs in the chondrogenic layer and cocultured with cells of different periods of osteogenic preculture (0, 3, 6 and 12 days) in the osteogenic layer to investigate the effects of TGF-beta3 delivery and coculture on the proliferation and differentiation of cells in both layers. The results showed that, in the chondrogenic layer, TGF-beta3 significantly stimulated chondrogenic differentiation of MSCs. In addition, cells of various osteogenic preculture periods in the osteogenic layer, along with TGF-beta3, enhanced gene expression for MSC chondrogenic markers to different extents. In the osteogenic layer, cells maintained their alkaline phosphatase activity during the coculture; however, mineralization was delayed by the presence of TGF-beta3. Overall, this study demonstrated the fabrication of bilayered hydrogel composites which mimic the structure and function of osteochondral tissue, along with the application of these composites as cell and growth factor carriers, while illustrating that encapsulated cells of different degrees of osteogenic differentiation can significantly influence the chondrogenic differentiation of cocultured progenitor cells in both the presence and absence of chondrogenic growth factors.
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224
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SU-EE-A1-04: Multiobjective Evolutionary Algorithm for IMRT Optimization: Development and Clinical Comparisons. Med Phys 2010. [DOI: 10.1118/1.3468009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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225
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Generation of Pig-Induced Pluripotent Stem Cells with a Drug-Inducible System. J Mol Cell Biol 2010. [DOI: 10.1093/jmcb/mjq004] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
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226
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Application of GC-Triple Quadrupole MS in the Quantitative Confirmation of Polycyclic Aromatic Hydrocarbons and Phthalic Acid Esters in Soil. J Chromatogr Sci 2010; 48:161-6. [DOI: 10.1093/chromsci/48.3.161] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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227
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In-hospital myocardial infarction following acute ischaemic stroke: an observational study. Eur J Neurol 2009; 16:1035-40. [DOI: 10.1111/j.1468-1331.2009.02647.x] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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228
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TU-C-BRB-04: Enhanced Modeling of Radiation Therapy for Head and Neck Cancers with Probabilistic Outcomes Using Mixed Predictors. Med Phys 2009. [DOI: 10.1118/1.3182329] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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229
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Mechanism-based inhibition of CYP1A2 by antofloxacin, an 8-NH2 derivative of levofloxacin in rats. Xenobiotica 2009; 39:293-301. [PMID: 19350452 DOI: 10.1080/00498250802709428] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
A recent focus was to investigate whether antofloxacin, an 8-NH(2) derivative of levofloxacin, inhibited cytochrome P450 (CYP) 1A2 activity in rats. Phenacetin, the representative substrate of CYP1A2, was used as the model drug to evaluate the activity of CYP1A2. In an in vivo study, an oral single dose of antofloxacin (20 mg kg(-1)) did not affect the pharmacokinetic behaviour of phenacetin, but a multidose (20 mg kg(-1) twice daily for 7.5 days) significantly increased phenacetin's area under the curve (AUC). In an in vitro study, only when pre-incubated with beta-nicotinamide adenine dinucleotide phosphate, a reduced form (NADPH) system in rat liver microsomes, did antofloxacin inhibit phenacetin O-deethylation. The inhibition was NADPH-, pre-incubation time-, and antofloxacin concentration-dependent. A physiologically based pharmacokinetic model with mechanism-based inhibition was successfully developed for predicting the interaction between antofloxacin and phenacetin in vivo from the in vitro data. The simulated AUC was 1.4-fold of the control, which was near the observed value of 1.6-fold. From the results, it can be concluded that the inhibition of CYP1A2 by antofloxacin is mechanism-based.
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Altered structural and mechanical properties in decellularized rabbit carotid arteries. Acta Biomater 2009; 5:993-1005. [PMID: 19135421 PMCID: PMC2680318 DOI: 10.1016/j.actbio.2008.11.028] [Citation(s) in RCA: 91] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2008] [Revised: 11/21/2008] [Accepted: 11/24/2008] [Indexed: 10/21/2022]
Abstract
Recently, major achievements in creating decellularized whole tissue scaffolds have drawn considerable attention to decellularization as a promising approach for tissue engineering. Decellularized tissues are expected to have mechanical strength and structure similar to the native tissues from which they are derived. However, numerous studies have shown that mechanical properties change after decellularization. Often, tissue structure is observed by histology and electron microscopy, but the structural alterations that may have occurred are not always evident. Here, a variety of techniques were used to investigate changes in tissue structure and relate them to altered mechanical behavior in decellularized rabbit carotid arteries. Histology and scanning electron microscopy revealed that major extracellular matrix components were preserved and fibers appeared intact, although collagen appeared looser and less crimped after decellularization. Transmission electron microscopy confirmed the presence of proteoglycans (PG), but there was decreased PG density and increased spacing between collagen fibrils. Mechanical testing and opening angle measurements showed that decellularized arteries had significantly increased stiffness, decreased extensibility and decreased residual stress compared with native arteries. Small-angle light scattering revealed that fibers had increased mobility and that structural integrity was compromised in decellularized arteries. Taken together, these studies revealed structural alterations that could be related to changes in mechanical properties. Further studies are warranted to determine the specific effects of different decellularization methods on the structure and performance of decellularized arteries used as vascular grafts.
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QS233. The Effects of Morbid Obesity on Post-Traumatic Infection. J Surg Res 2009. [DOI: 10.1016/j.jss.2008.11.535] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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232
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Quality Assurance of QA Rounds: A Prospective Audit Tracks Practice Performance. Int J Radiat Oncol Biol Phys 2008. [DOI: 10.1016/j.ijrobp.2008.06.1424] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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233
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Positive margins in laparoscopic partial nephrectomy in 855 cases: a multi-institutional survey from the United States and Europe. J Urol 2007; 178:47-50; discussion 50. [PMID: 17574057 DOI: 10.1016/j.juro.2007.03.045] [Citation(s) in RCA: 92] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2006] [Indexed: 12/17/2022]
Abstract
PURPOSE Open partial nephrectomy has emerged as the standard of care in the management of renal tumors smaller than 4 cm. While laparoscopic radical nephrectomy has been shown to be comparable to open radical nephrectomy with respect to long-term outcomes, important questions remain unanswered regarding the oncological efficacy of laparoscopic partial nephrectomy. We examined the practice patterns and pathological outcomes following laparoscopic partial nephrectomy. MATERIALS AND METHODS A survey was sent to academic medical centers in the United States and in Europe performing laparoscopic partial nephrectomy. The total number of laparoscopic partial nephrectomies, positive margins, indications for intraoperative frozen biopsy as well as tumor size and position were queried. RESULTS Surveys suitable for analysis were received from 17 centers with a total of 855 laparoscopic partial nephrectomy cases. Mean tumor size was 2.7 cm (+/-0.6). There were 21 cases with positive margins on final pathology, giving an overall positive margin rate of 2.4%. Intraoperative frozen sections were performed selectively at 10 centers based on clinical suspicion of positive margins on excised tumor. Random biopsies were routinely performed on the resection bed at 5 centers. Frozen sections were never performed at 2 centers. Of the 21 cases with positive margins 14 underwent immediate radical nephrectomy based on the frozen section and 7 were followed expectantly. CONCLUSIONS Early experience with laparoscopic partial nephrectomy in this multicenter study demonstrates oncological efficacy comparable to that of open partial nephrectomy with respect to the incidence of positive margins. The practice of intraoperative frozen sections varied among centers and is not definitive in guiding the optimal surgical treatment.
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Effects of altitudinal change on the auditory bulla in Ochotona daurica (Mammalia, Lagomorpha). J ZOOL SYST EVOL RES 2007. [DOI: 10.1111/j.1439-0469.2006.00401.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Complications of laparoscopic living donor nephrectomy and their management: the UCLA experience. Urology 2007; 69:49-52. [PMID: 17270612 DOI: 10.1016/j.urology.2006.09.030] [Citation(s) in RCA: 66] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2006] [Accepted: 09/12/2006] [Indexed: 01/02/2023]
Abstract
OBJECTIVES Because of the shortage of cadaveric kidneys, laparoscopic living donor nephrectomy (LLDN) has become a more common option for transplant recipients. The complication rate has been reported at 6.4% to 16.5%. We present the initial University of California, Los Angeles experience with the complications and their management during LLDN. METHODS From January 2000 to December 2005, a single surgeon performed 300 consecutive LLDNs at our institution. A committee of urologists, nephrologists, and support staff approved each donor before surgery. After LLDN was completed, the patients received 30 mg of ketorolac intravenously every 6 hours until discharge. We reviewed the intraoperative and postoperative complications and their management at our institution. RESULTS Three patients required open conversion, for an overall conversion rate of 1%. Two of the three conversions were a result of a major vascular complication (0.6%). The first major vascular complication resulted from an endovascular stapler malfunction during transection of an accessory left renal artery. The second vascular complication was a Veress needle injury to the left common iliac artery. Three postoperative major complications (1%) occurred, including 1 case of rhabdomyolysis and 2 cases of chylous ascites. Also, 7 minor postoperative complications (2.3%) occurred. Our overall complication rate was 4%. No patients died, and the mean hospital stay was 1.1 days. CONCLUSIONS Our results have shown that LLDN is a safe procedure associated with low morbidity and a quick recovery. Appropriate patient selection is essential to ensure the safety of this procedure.
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The 22q11 deletion syndrome candidate gene Tbx1 determines thyroid size and positioning. Hum Mol Genet 2006; 16:276-85. [PMID: 17164259 DOI: 10.1093/hmg/ddl455] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Thyroid dysgenesis is the major cause of congenital hypothyroidism in humans. The underlying molecular mechanism is in most cases unknown, but the frequent co-incidence of cardiac anomalies suggests that the thyroid morphogenetic process may depend on proper cardiovascular development. The T-box transcription factor TBX1, which is the most probable gene for the 22q11 deletion syndrome (22q11DS/DiGeorge syndrome/velo-cardio-facial syndrome), has emerged as a central player in the coordinated formation of organs and tissues derived from the pharyngeal apparatus and the adjacent secondary heart field from which the cardiac outflow tract derives. Here, we show that Tbx1 impacts greatly on the developing thyroid gland, although it cannot be detected in the thyroid primordium at any embryonic stage. Specifically, in Tbx1-/- mice, the downward translocation of Titf1/Nkx2.1-expressing thyroid progenitor cells is much delayed. In late mutant embryos, the thyroid fails to form symmetric lobes but persists as a single mass approximately one-fourth of the normal size. The hypoplastic gland mostly attains a unilateral position resembling thyroid hemiagenesis. The data further suggest that failure of the thyroid primordium to re-establish contact with the aortic sac is a key abnormality preventing normal growth of the midline anlage along the third pharyngeal arch arteries. In normal development, this interaction may be facilitated by Tbx1-expressing mesenchyme filling the gap between the pharyngeal endoderm and the detached thyroid primordium. The findings indicate that Tbx1 regulates intermediate steps of thyroid development by a non-cell-autonomous mechanism. Thyroid dysgenesis related to Tbx1 inactivation may explain an overrepresentation of hypothyroidism occurring in patients with the 22q11DS.
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[Comparison of IgA/VCA, IgA/EA, IgG/EA in immunoenzyme methods and ZEBRA ELISA in early diagnosis of nasopharyngeal carcinoma.]. ZHONGHUA SHI YAN HE LIN CHUANG BING DU XUE ZA ZHI = ZHONGHUA SHIYAN HE LINCHUANG BINGDUXUE ZAZHI = CHINESE JOURNAL OF EXPERIMENTAL AND CLINICAL VIROLOGY 2006; 20:263-5. [PMID: 17086289] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
BACKGROUND To develop an ELISA method using Herpesvirus hominis type 4 (EBV) IgG/Zebra as capture antigen for large population screening. METHODS The ELISA method used purified ZEBRA antigen to detect the IgG/ZEBRA antibody from serum in nasopharyngeal carcinoma (NPC) and normal healthy subjects. RESULTS Of 288 NPC sera, 262 were detected positive, the sensitivity was 91%, while 5 of 96 normal sera were detected positive, the specificity was 94.8% and the results of NPC group and healthy group displayed significant difference (P less than 0.001). IgA/VCA, IgA/EA, IgG/EA in immunoenzyme methods and ZEBRA ELISA were compared during the NPC screening in two cities: Huizhou, Guangdong and Guiping, Guangxi, 5463 and 2017 samples respectively were tested and 5 earlier NPC patients were found. CONCLUSION The results indicate that this method has high specificity and sensitivity, and can be used for large population screening to assist early phase NPC diagnosis.
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Xenogeneic immunization with tyrosinase DNA vaccines: results from clinical trials in humans and dogs. Melanoma Res 2006. [DOI: 10.1097/00008390-200609001-00081] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Abstract
INTRODUCTION Canine malignant melanoma (CMM) is an aggressive neoplasm treated with surgery and/or fractionated RT; however, metastatic disease is common and chemoresistant. Preclinical and clinical studies by our laboratory and others have shown that xenogeneic DNA vaccination with tyrosinase family members can produce immune responses resulting in tumor rejection or protection and prolongation of survival. These studies provided the impetus for development of a xenogeneic DNA vaccine program in CMM. MATERIALS AND METHODS Cohorts of three dogs each received increasing doses of xenogeneic plasmid DNA encoding either human tyrosinase (huTyr; 100/500/1500 mcg), murine GP75 (muGP75; 100/500/1500 mcg), murine tyrosinase (muTyr; 5 dogs each at 100/500 mcg), muTyr+/-HuGM-CSF (9 dogs at 50 mcg muTyr, 3 dogs each at 100/400/800 mcg HuGM-CSF, or 3 dogs each at 50 mcg muTyr with 100/400/800 mcg HuGM-CSF), or 50 mcg MuTyr intramuscularly biweekly for a total of four vaccinations. RESULTS The Kaplan-Meier median survival time (KM MST) for all stage II-IV dogs treated with huTyr, muGP75 and muTyr are 389, 153 and 224 days, respectively. Preliminarily, the KM MST for stage II-IV dogs treated with 50 mcg MuTyr, 100/400/800 mcg HuGM-CSF or combination MuTyr/HuGM-CSF are 242, 148 and >402 (median not reached) days, respectively. Thirty-three stage II-III dogs with loco-regionally controlled CMM across the xenogeneic vaccine studies have a KM MST of 569 days. Minimal to mild pain was noted on vaccination and one dog experienced vitiligo. We have recently investigated antibody responses in dogs vaccinated with HuTyr and found 2- to 5-fold increases in circulating antibodies to human tyrosinase. CONCLUSIONS The results of these trials demonstrate that xenogeneic DNA vaccination in CMM: (1) is safe, (2) leads to the development of anti-tyrosinase antibodies, (3) is potentially therapeutic, and (4) is an attractive candidate for further evaluation in an adjuvant, minimal residual disease Phase II setting for CMM.
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Structural and biaxial mechanical properties of decellularized aortic valve leaflets. J Biomech 2006. [DOI: 10.1016/s0021-9290(06)85570-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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241
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Crystal structure of the small G protein M-Ras and its implications. Acta Crystallogr A 2005. [DOI: 10.1107/s010876730509015x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
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[Determination of polysaccharides of Dendrobium candidum in test-tube culture]. ZHONG YAO CAI = ZHONGYAOCAI = JOURNAL OF CHINESE MEDICINAL MATERIALS 2005; 28:450-1. [PMID: 16209260] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
OBJECTIVE To investigate the diversities of polysaccharides content of Dendrobium candidum and its test-tube culture. METHODS The content of polysaccharides was determined by colorimentry. RESULTS The content of polysaccharides extracted from Dendrobium candidum was higher than that of test-tube culture. CONCLUSION The content of polysaccharides in protocorm is higher than that in test-tube plantlet.
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Xenogeneic Human Tyrosinase DNA Vaccination Induces Specific Immune Response in Dogs with Advanced Malignant Melanoma. Vet Comp Oncol 2005. [DOI: 10.1111/j.1476-5810.2005.0064y.x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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244
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Phase I & Ib Trials of Murine Tyrosinase ± Human GM-CSF DNA Vaccination in Dogs with Advanced Malignant Melanoma. Vet Comp Oncol 2005. [DOI: 10.1111/j.1476-5810.2005.0064g.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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52 SUB-CLINICAL IMFLAMMATION CONTRIBUTES TO THE EARLY DEVELOPMENT OF CARDIOVASCULAR DISEASE IN THE NON-HYPERENSIVE YOUNG HEALTHY PREFESSIONALS. J Investig Med 2005. [DOI: 10.2310/6650.2005.00006.51] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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177 DECREASED ALVEOLAR SEPTATION DUE TO IN UTERO NICOTINE EXPOSURE IS ASSOCIATED WITH DECREASED SLIT/ROBO EXPRESSION. J Investig Med 2005. [DOI: 10.2310/6650.2005.00005.176] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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53 AMBULATORY BLOOD PRESSURE MONITOR IS SUPERIOR TO THE OFFICE BLOOD PRESSURE IN PREDICTING THE EARLY VASCULAR PATHOLOGY IN NON-HYPERTENSIVE YOUNG PROFESSIONALS. J Investig Med 2005. [DOI: 10.2310/6650.2005.00006.52] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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Abstract
The frequency of use of traditional Chinese drugs was investigated in relation to Western and Chinese diagnostic classifications in a hospital for traditional Chinese medicine in Germany. All 1597 in-patients treated in the hospital between February 1992 and August 1993 entered a prospective observational study. About two thirds of the patients suffered from chronic pain syndromes, the most frequent single diagnosis being migraine (n=244). All patients were treated with at least one of four Chinese therapies (traditional Chinese drugs, acupuncture, Tuina-massage, Qi-gong). 95.1% of all patients received traditional Chinese drug treatment, prescribed in complex prescriptions including 3 to 12 single drugs from a total of 305. Drug patterns prescribed to patients with the same Western diagnosis tended to be similar, but could differ strongly for single drugs in subgroups with distinct Chinese diagnoses. Studies evaluating traditional Chinese treatment strategies in patients classified according to Western nosology should take into account possible diagnostic differences according to Chinese nosology. The development of a reliable coding system for Chinese diagnostic classifications is a precondition for further cross-cultural studies.
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Abstract
The frequency of use of traditional Chinese drugs was investigated in relation to Western and Chinese diagnostic classifications in a hospital for traditional Chinese medicine in Germany. All 1597 in-patients treated in the hospital between February 1992 and August 1993 entered a prospective observational study. About two thirds of the patients suffered from chronic pain syndromes, the most frequent single diagnosis being migraine (n=244). All patients were treated with at least one of four Chinese therapies (traditional Chinese drugs, acupuncture, Tuina-massage, Qi-gong). 95.1% of all patients received traditional Chinese drug treatment, prescribed in complex prescriptions including 3 to 12 single drugs from a total of 305. Drug patterns prescribed to patients with the same Western diagnosis tended to be similar, but could differ strongly for single drugs in subgroups with distinct Chinese diagnoses. Studies evaluating traditional Chinese treatment strategies in patients classified according to Western nosology should take into account possible diagnostic differences according to Chinese nosology. The development of a reliable coding system for Chinese diagnostic classifications is a precondition for further cross-cultural studies.
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Induction of hypoxic root metabolism results from physical limitations in O2 bioavailability in microgravity. ADVANCES IN SPACE RESEARCH : THE OFFICIAL JOURNAL OF THE COMMITTEE ON SPACE RESEARCH (COSPAR) 2004; 34:1579-84. [PMID: 15880895 DOI: 10.1016/j.asr.2004.02.002] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/02/2023]
Abstract
Numerous spaceflight experiments have noted changes in the roots that are consistent with hypoxia in the root zone. These observations include general ultrastructure analysis and biochemical measurements to direct measurements of stress specific enzymes. In experiments that have monitored alcohol dehydrogenase (ADH), the data shows this hypoxically responsive gene is induced and is associated with increased ADH activity in microgravity. These changes in ADH could be induced either by spaceflight hypoxia resulting from inhibition of gravity mediated O2 transport, or by a non-specific stress response due to inhibition of gravisensing. We tested these hypotheses in a series of two experiments. The objective of the first experiment was to determine if physical changes in gravity-mediated O2 transport can be directly measured, while the second series of experiments tested whether disruption of gravisensing can induce a non-specific ADH response. To directly measure O2 bioavailability as a function of gravity, we designed a sensor that mimics metabolic oxygen consumption in the rhizosphere. Because of these criteria, the sensor is sensitive to any changes in root O2 bioavailability that may occur in microgravity. In a KC-135 experiment, the sensor was implanted in a moist granular clay media and exposed to microgravity during parabolic flight. The resulting data indicated that root O2 bioavailability decreased in phase with gravity. In experiments that tested for non-specific induction of ADH, we compared the response of transgenic Arabidopsis plants (ADH promoted GUS marker gene) exposed to clinostat, control, and waterlogged conditions. The plants were grown on agar slats in a growth chamber before being exposed to the experimental treatments. The plants were stained for GUS activity localization, and subjected to biochemical tests for ADH, and GUS enzyme activity. These tests showed that the waterlogging treatment induced significant increases in GUS and ADH enzyme activities, while the control and clinostat treatments showed no response. This work demonstrates: (1) the inhibition of gravity-driven convective transport can reduce the O2 bioavailability to the root tip, and (2) the perturbation of gravisensing by clinostat rotation does not induce a nonspecific stress response involving ADH. Together these experiments support the microgravity convection inhibition model for explaining changes in root metabolism during spaceflight.
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