76
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Borisenko SV, Kordyuk AA, Koitzsch A, Kim TK, Nenkov KA, Knupfer M, Fink J, Grazioli C, Turchini S, Berger H. Circular dichroism in angle-resolved photoemission spectra of under- and overdoped Pb-Bi2212. PHYSICAL REVIEW LETTERS 2004; 92:207001. [PMID: 15169374 DOI: 10.1103/physrevlett.92.207001] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/07/2003] [Indexed: 05/24/2023]
Abstract
We use angle-resolved photoemission with circularly polarized excitation to demonstrate that in the 5 x 1 superstructure-free (Pb,Bi)(2)Sr(2)CaCu(2)O(8+delta) (Pb-Bi2212) material there are no signatures of time-reversal symmetry breaking in the sense of the criteria developed earlier [Nature (London) 416, 610 (2002)]]. The dichroic signal retains reflection antisymmetry as a function of temperature and doping and in all mirror planes, precisely defined by the experimental dispersion at low energies. The obtained results demonstrate that the signatures of time-reversal symmetry violation in pristine Bi2212, as determined by angle-resolved photoemission spectroscopy, are not a universal feature of all cuprate superconductors.
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77
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Cousins BG, Doherty PJ, Williams RL, Fink J, Garvey MJ. The effect of silica nanoparticulate coatings on cellular response. JOURNAL OF MATERIALS SCIENCE. MATERIALS IN MEDICINE 2004; 15:355-359. [PMID: 15332599 DOI: 10.1023/b:jmsm.0000021101.64938.b3] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
The current techniques used to create patterned materials at the nanometer scale such as electron beam lithography are restricted to patterning small areas, which can be expensive and time consuming. A simple, cost-effective approach has been developed to create a reproducible surface topography to influence the cellular response. In this study, the cellular response of murine fibroblasts to 7, 14 and 21 nm colloidal silica particles were investigated over one, three and seven days and up to seven weeks. The surface topography and wettability of the surfaces were also studied. The results confirmed that silica particles create a nanoscale topography, which initiates a distinctive cellular response affecting the morphology, adhesion and proliferation of the fibroblasts. The effect was evident up to seven weeks with no adverse effects on cell viability.
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78
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Dequin P, Mercier E, Valat C, Fishman R, Fink J, Smith N, Gibbons K, Diot P. Crit Care 2004; 8:P229. [DOI: 10.1186/cc2696] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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79
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Kim TK, Kordyuk AA, Borisenko SV, Koitzsch A, Knupfer M, Berger H, Fink J. Doping dependence of the mass enhancement in (Pb,Bi)2Sr2CaCu2O8 at the antinodal point in the superconducting and normal states. PHYSICAL REVIEW LETTERS 2003; 91:167002. [PMID: 14611429 DOI: 10.1103/physrevlett.91.167002] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/20/2003] [Indexed: 05/24/2023]
Abstract
Angle-resolved photoemission spectroscopy is used to study the mass renormalization of the charge carriers in the high-T(c) superconductor (Pb,Bi)2Sr2CaCu2O8 in the vicinity of the (pi,0) point in the superconducting and the normal states. Using matrix element effects at different photon energies and due to a high momentum and energy resolution the bonding and the antibonding bands could be separated in the whole dopant range. A huge coupling to a bosonic collective mode is observed below T(c) for both bands, in particular, for the underdoped case. Above T(c), a weaker coupling to a continuous spectrum of modes is detected.
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80
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Borowiak-Palen E, Pichler T, Fuentes G, Graff A, Kalenczuk R, Knupfer M, Fink J. Efficient production of B-substituted single-wall carbon nanotubes. Chem Phys Lett 2003. [DOI: 10.1016/s0009-2614(03)01324-1] [Citation(s) in RCA: 68] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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81
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Moskvin AS, Málek J, Knupfer M, Neudert R, Fink J, Hayn R, Drechsler SL, Motoyama N, Eisaki H, Uchida S. Evidence for two types of low-energy charge transfer excitations in Sr2CuO3. PHYSICAL REVIEW LETTERS 2003; 91:037001. [PMID: 12906439 DOI: 10.1103/physrevlett.91.037001] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/30/2002] [Revised: 03/07/2003] [Indexed: 05/24/2023]
Abstract
A comparative analysis of electron energy-loss spectroscopy (EELS) spectra for the 1D insulating cuprate Sr2CuO3 with transferred momentum q--> axially and radially to the chain axis allows one to elucidate the structure of the charge transfer gap in in-chain response. It is determined by the superposition of two types of excitations with different magnitudes of dispersion. The low-energy response with q--> radially to the chain direction, but yet within the plane of CuO4 plaquettes, exhibits also a dispersionless peak near 2 eV. The theoretical simulation of the EELS data using exact diagonalizations of an appropriate extended Hubbard Hamiltonian for relevant clusters requires the explicit consideration of low-lying oxygen 2p pi states within the CuO4 plaquette plane beyond the standard pd sigma extended Hubbard model widely used for cuprates with corner-shared CuO4 plaquettes.
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82
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Borisenko SV, Kordyuk AA, Kim TK, Koitzsch A, Knupfer M, Fink J, Golden MS, Eschrig M, Berger H, Follath R. Anomalous enhancement of the coupling to the magnetic resonance mode in underdoped Pb-Bi2212. PHYSICAL REVIEW LETTERS 2003; 90:207001. [PMID: 12785915 DOI: 10.1103/physrevlett.90.207001] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/18/2002] [Indexed: 05/24/2023]
Abstract
High-resolution angle-resolved photoemission with variable excitation energies is used to disentangle bilayer splitting effects and intrinsic (self-energy) effects in the electronic spectral function near the (pi,0) point of differently doped (Pb,Bi)(2)Sr(2)CaCu(2)O(8+delta). In contrast to overdoped samples, where intrinsic effects at the (pi,0) point are virtually absent, we find in underdoped samples intrinsic effects in the superconducting-state (pi,0) spectra of the antibonding band. This intrinsic effect is present only below the critical temperature and weakens considerably with doping. Our results give strong support for models which involve a strong coupling of electronic excitations with the resonance mode seen in inelastic neutron scattering experiments.
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83
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Borowiak-Palen E, Pichler T, Fuentes GG, Bendjemil B, Liu X, Graff A, Behr G, Kalenczuk RJ, Knupfer M, Fink J. Infrared response of multiwalled boron nitride nanotubes. Chem Commun (Camb) 2003:82-3. [PMID: 12610976 DOI: 10.1039/b208214d] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
We report the infrared (IR) response of bulk samples of multiwalled boron nitride nanotubes, produced by a substitution reaction from single walled carbon nanotubes, which is dominated by two characteristic BN-vibrations at 800 and 1372 cm-1.
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84
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Hu Z, Golden M, Ebbinghaus S, Knupfer M, Fink J, de Groot F, Kaindl G. The distribution of the doped holes in La2−xSrxCu1−yRuyO4−δ. Chem Phys 2002. [DOI: 10.1016/s0301-0104(02)00729-2] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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85
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Borowiak-Palen E, Pichler T, Liu X, Knupfer M, Graff A, Jost O, Pompe W, Kalenczuk R, Fink J. Reduced diameter distribution of single-wall carbon nanotubes by selective oxidation. Chem Phys Lett 2002. [DOI: 10.1016/s0009-2614(02)01253-8] [Citation(s) in RCA: 78] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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86
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Kordyuk AA, Borisenko SV, Kim TK, Nenkov KA, Knupfer M, Fink J, Golden MS, Berger H, Follath R. Origin of the peak-dip-hump line shape in the superconducting-state (pi,0) photoemission spectra of Bi2Sr2CaCu2O8. PHYSICAL REVIEW LETTERS 2002; 89:077003. [PMID: 12190550 DOI: 10.1103/physrevlett.89.077003] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/18/2001] [Indexed: 05/23/2023]
Abstract
From detailed high-resolution measurements of the photon energy dependence of the (pi,0) superconducting-state photoemission spectrum of the bilayer Bi high-temperature superconductors, we show that the famous peak-dip-hump line shape is dominated by a superposition of spectral features originating from different electronic states which reside at different binding energies, but are each describable by essentially identical single-particle spectral functions. The previously identified bilayer-split CuO2 bands are the culprit: with the "superconducting" peak being due to the antibonding band, while the hump is mainly formed by its bonding bilayer-split counterpart.
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87
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Marinopoulos AG, Reining L, Olevano V, Rubio A, Pichler T, Liu X, Knupfer M, Fink J. Anisotropy and interplane interactions in the dielectric response of graphite. PHYSICAL REVIEW LETTERS 2002; 89:076402. [PMID: 12190537 DOI: 10.1103/physrevlett.89.076402] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/18/2002] [Indexed: 05/23/2023]
Abstract
We determined the anisotropic dielectric response of graphite by means of time-dependent density-functional theory and high-resolution valence electron energy-loss spectroscopy. The calculated loss function was in very good agreement with the experiment for a wide range of momentum-transfer orientations with respect to the graphitic basal planes, provided that local-field effects were included in the response. The calculations also showed strong effects of the interlayer Coulomb interaction on the total pi+sigma plasmon. This finding must be taken into account for the explanation of recent loss spectra of carbon nanotube materials.
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88
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Ruebsam M, Dinse KP, Plueschau M, Fink J, Kraetschmer W, Fostiropoulos K, Taliani C. Fourier-transform EPR investigation of photo-generated radical anions of C60 in solution. J Am Chem Soc 2002. [DOI: 10.1021/ja00051a047] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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89
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Gaber H, Busmann HG, Hiss R, Hertel IV, Romberg H, Fink J, Bruder F, Brenn R. Carbon films of amorphous and oriented graphitic structure from fullerene ion beam deposition. ACTA ACUST UNITED AC 2002. [DOI: 10.1021/j100133a021] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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90
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Yoshimura N, Franks ME, Sasaki K, Goins WF, Goss J, Yokoyama T, Fraser MO, Seki S, Fink J, Glorioso J, de Groat WC, Chancellor MB. Gene therapy of bladder pain with herpes simplex virus (HSV) vectors expressing preproenkephalin (PPE). Urology 2002; 57:116. [PMID: 11378092 DOI: 10.1016/s0090-4295(01)01060-3] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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91
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Jost O, Gorbunov AA, Möller J, Pompe W, Liu X, Georgi P, Dunsch L, Golden MS, Fink J. Rate-Limiting Processes in the Formation of Single-Wall Carbon Nanotubes: Pointing the Way to the Nanotube Formation Mechanism. J Phys Chem B 2002. [DOI: 10.1021/jp013138s] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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92
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Wilkes W, Fink J, Dhand R. Selecting an accessory device with a metered-dose inhaler: variable influence of accessory devices on fine particle dose, throat deposition, and drug delivery with asynchronous actuation from a metered-dose inhaler. JOURNAL OF AEROSOL MEDICINE : THE OFFICIAL JOURNAL OF THE INTERNATIONAL SOCIETY FOR AEROSOLS IN MEDICINE 2002; 14:351-60. [PMID: 11693847 DOI: 10.1089/089426801316970312] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Accessory devices reduce common problems with metered-dose inhalers (MDIs), namely high oropharyngeal deposition of aerosol and incoordination between actuation and inhalation by the patient. The objective of this study was to systematically compare the performance of various accessory devices in vitro. MDIs were tested alone or in combination with four spacers (Toilet paper roll, Ellipse, Optihaler, Myst Assist) and five holding chambers (Aerochamber, Optichamber, Aerosol Cloud Enhancer, Medispacer, and Inspirease). An Anderson cascade impactor was used to measure aerosol mass median aerodynamic diameter (MMAD) and fine particle dose (MMAD < 4.7 microm). In separate experiments, the influence of asynchronous MDI actuation on drug delivery was determined with a simulated spontaneous breathing model. Compared with the MDI alone, all of the accessory devices reduced aerosol MMAD and increased lung-throat ratio (fine particle dose/throat impaction; p < 0.05 for both parameters). The fine particle dose of albuterol was 40% higher with the Ellipse (p < 0.01), was equivalent with the Toilet Paper Roll, Aerochamber, Optichamber, and Medispacer, and was 33-56% lower with the Optihaler, Myst Assist, Aerosol Cloud Enhancer, and Inspirease (p < 0.03). MDI actuation in synchrony with inspiration produced highest drug delivery; when MDI actuation occurred 1-sec before inspiration or during exhalation, decrease in drug delivery with holding chambers (10-40% reduction) was less than that with spacers (40-90% reduction). Accessory device selection is complicated by variability in performance between devices, and in the performance of each device in different clinical settings. In vitro characterization of a MDI and accessory device could guide appropriate device selection in various clinical settings.
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93
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Leonhardt A, Ritschel M, Bartsch K, Graff A, Täschner C, Fink J. Chemical vapour deposition - a promising method for production of different kinds of carbon nanotubes. ACTA ACUST UNITED AC 2001. [DOI: 10.1051/jp4:2001356] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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94
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Krill G, Lapierre MF, Robert C, Gautier F, Czjzek G, Fink J, Schmidt H. Electronic and magnetic properties of the pyrite-structure compound NiS2: influence of vacancies and copper impurities. ACTA ACUST UNITED AC 2001. [DOI: 10.1088/0022-3719/9/5/016] [Citation(s) in RCA: 58] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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95
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Fink J, Blahut S, Reddy M, Light P. Use of erythropoietin before the initiation of dialysis and its impact on mortality. Am J Kidney Dis 2001; 37:348-55. [PMID: 11157377 DOI: 10.1053/ajkd.2001.21305] [Citation(s) in RCA: 105] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Erythropoietin (EPO) is recommended in individuals progressing toward end-stage renal disease (ESRD) to correct anemia and its complications, which are common in this disease. This study evaluated the impact of EPO administered before dialysis on mortality in incident ESRD patients. A total of 4,866 patients whose exposure to pre-ESRD EPO was determined from Health Care Financing Administration 2728 forms were analyzed. The median follow-up was 26.2 months, with 1,107 (22.7%) patients given EPO and 1,892 (38.9%) deaths. EPO use was more common in patients who had insurance before dialysis, remained employed, were started on renal replacement therapy outside the hospital, or initiated on peritoneal dialysis, which could be indicative of early intervention or quality care. The risk of death after starting dialysis was lower for patients treated with EPO before dialysis compared with patients who were not treated (adjusted relative risk 0.80, 95% confidence interval 0.70 to 0.91). There was no direct relationship between predialysis hematocrit and mortality; however, the most significant survival benefit with EPO use was in patients with the highest hematocrit values (adjusted relative risk 0.67, 95% confidence interval, 0.51 to 0.89). The most significant effect of pre-ESRD EPO use was observed during the first 19 months after starting dialysis (adjusted relative risk, 0.81; 95% confidence interval, 0.71 to 0.91), but this benefit diminished in patients with longer follow-up on renal replacement therapy. Use of EPO before dialysis confers a survival benefit to ESRD patients, especially in patients with an adequate hematocrit response before initiation of dialysis.
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96
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Brusetti R, Coey JMD, Czjek G, Fink J, Gompf F. The role of the lattice at the metal-semimetal transition in nickel sulphide. ACTA ACUST UNITED AC 2000. [DOI: 10.1088/0305-4608/10/1/013] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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97
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Manzke R, Crecelius G, Fink J, Trinkaus H, Jager W. Formation of He bubbles in Al films irradiated with He ions. ACTA ACUST UNITED AC 2000. [DOI: 10.1088/0305-4608/12/12/007] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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98
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Jacobs SC, Cho E, Dunkin BJ, Flowers JL, Schweitzer E, Cangro C, Fink J, Farney A, Philosophe B, Jarrell B, Bartlett ST. Laparoscopic live donor nephrectomy: the University of Maryland 3-year experience. J Urol 2000; 164:1494-9. [PMID: 11025690] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/17/2023]
Abstract
PURPOSE We determined whether laparoscopic living donor nephrectomy decreases the morbidity of renal donation for the donor, while providing a renal allograft of a quality comparable to that of open donor nephrectomy. MATERIALS AND METHODS In a 3-year period laparoscopic donor nephrectomy was performed via the transperitoneal approach. We evaluated donor and recipient medical records for preoperative donor characteristics, intraoperative parameters and complications, and postoperative recovery and complications. RESULTS Of the 320 laparoscopic donor nephrectomies performed the left kidney was removed in 97.5%. Intraoperative complications, which developed in 10.4% of cases, tended to occur early in the experience and required conversion to open nephrectomy in 5. Average operative time was 31/2 hours and warm ischemia time was 21/2 minutes. As the series progressed, blood loss as well as laparoscopic port size and number decreased but extraction site size remained constant at 7 cm. Urinary retention, prolonged ileus, thigh numbness and incisional hernia were the most common postoperative complications. Postoperative analgesic requirements were low and average hospitalization was 66 hours. CONCLUSIONS Laparoscopic donor nephrectomy appears to be safe and decreases morbidity in the renal donor. Allograft function is comparable to that in open nephrectomy series. The availability of laparoscopic harvesting may be increasing the living donor volunteer pool.
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99
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Borisenko SV, Golden MS, Legner S, Pichler T, Durr C, Knupfer M, Fink J, Yang G, Abell S, Berger H. Joys and pitfalls of fermi surface mapping in Bi(2)Sr(2)CaCu(2)O(8+delta) using angle resolved photoemission. PHYSICAL REVIEW LETTERS 2000; 84:4453-4456. [PMID: 10990709 DOI: 10.1103/physrevlett.84.4453] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/15/1999] [Indexed: 05/23/2023]
Abstract
On the basis of angle-scanned photoemission data recorded using unpolarized radiation, with high (E,k) resolution, and an extremely dense sampling of k space, we resolve the current controversy regarding the normal state Fermi surface (FS) in Bi(2)Sr(2)CaCu(2)O(8+delta). The true picture is simple, self-consistent, and robust: the FS is holelike, with the form of rounded tubes centered on the corners of the Brillouin zone. Two further types of features are also clearly observed: shadow FSs, which are most likely to be due to short range antiferromagnetic spin correlations, and diffraction replicas of the main FS caused by passage of the photoelectrons through the modulated Bi-O planes.
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100
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Fink J, Dhand R. Bronchodilator resuscitation in the emergency department. Part 2 of 2: dosing strategies. Respir Care 2000; 45:497-512. [PMID: 10813227] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/16/2023]
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