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Zhao Z, Li B, Yin Y, Wang Z, Fu Z, Fang S, Liu T, Sun H. Study on Different SPECT/CT Image Registration Methods using Motion-phantom. Int J Radiat Oncol Biol Phys 2008. [DOI: 10.1016/j.ijrobp.2008.06.285] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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77
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Mao L, Qiu YD, Fang S, Wu YF, Liu H, Ding YT. Liver Progenitor Cells Activated After 30% Small-for-Size Liver Transplantation in Rats: A Preliminary Study. Transplant Proc 2008; 40:1635-40. [DOI: 10.1016/j.transproceed.2008.03.133] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2007] [Accepted: 03/06/2008] [Indexed: 02/07/2023]
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78
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Srokowski TP, Fang S, Hortobagyi GN, Giordano SH. Impact of diabetes mellitus on complications of chemotherapy and outcomes in older patients with breast cancer. J Clin Oncol 2008. [DOI: 10.1200/jco.2008.26.15_suppl.553] [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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79
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Zhou G, Ren S, Chen N, Duan L, Zhang Z, Fang S, Zhao W. Cerebral White Matter Lesions and Cognitive Function in a Non-demented Chinese Veteran Cohort. J Int Med Res 2008; 36:115-22. [PMID: 18230275 DOI: 10.1177/147323000803600115] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
This study examined the association between cerebral white matter lesions (WMLs) and cognitive function in a male, non-demented Chinese veteran cohort. A total of 662 participants underwent CT scan and cognitive function assessments; 51 were excluded from the analysis because they exhibited non-lacunar infarcts or suspected dementia. Subjects were allocated to one of four groups according to WML status and between-group comparisons were made for seven cognitive function tests. Logistic regression was used to assess odds ratios for impaired performance associated with WML status. In all cognitive tests, subjects with severe WMLs differed significantly from those without WMLs or with mild WMLs, and in three tests subjects with severe WMLs differed significantly from those with moderate WMLs. For each cognitive test severe WMLs were strongly associated with increased risk of impaired performance. Severe WMLs were associated with greater diminished cognitive function and there may be a WML threshold after which, in elderly Chinese subjects, an impact on cognitive function occurs.
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Fang S, Xue J, Tang L. Biomass production and carbon sequestration potential in poplar plantations with different management patterns. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2007; 85:672-9. [PMID: 17110018 DOI: 10.1016/j.jenvman.2006.09.014] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/02/2005] [Revised: 07/24/2006] [Accepted: 09/27/2006] [Indexed: 05/12/2023]
Abstract
Biomass production and carbon storage in short-rotation poplar plantations over 10 years were evaluated at the Hanyuan Forestry Farm, Baoying County, China. Experimental treatments applied in a split-plot design included four planting densities (1111, 833, 625 and 500 stems ha(-1)) and three poplar clones (NL-80351, I-69 and I-72). Based on the model of total biomass production developed, total plantation biomass production was significantly different in the plantations. The ranking of the plantation biomass production by planting density was 1111>833 more more than 625>500 stems ha(-1), and by components was stem>root>or=branch>leaf for all plantations. At 10 years, the highest total biomass in the plantation of 1111 stems ha(-1) reached about 146 t ha(-1), which was 5.3%, 11.6% and 24.2% higher than the plantations of 833, 625 and 500 stems ha(-1), respectively. The annual increment of biomass production over 10 years differed significantly among initial planting densities and stand ages (p<0.01), but no significant difference was observed from age 7 to 10. Mean carbon concentration among all biomass components ranged from 42-50%, with the highest carbon concentrations in stems and the lowest in leaves. Over the study period, the dynamic pattern of total plantation carbon storage by planting density was similar to that of total biomass production. At age 10, the highest total plantation carbon storage in the plantation of 1111 stems ha(-1) reached about 72.0 t ha(-1), which was 5.4%, 11.9% and 24.8% higher than in the plantations of 833, 625 and 500 stems ha(-1), respectively. The annual carbon storage increment over 10 years differed significantly among initial planting densities and stand ages (p<0.01), and it showed a pattern similar to the annual biomass production increment of the plantations. The results suggest that biomass production and carbon storage potential were highest for planting densities of 1111 and 833 stems ha(-1) grown over 5- and 6-year cutting cycles, respectively. If 3- or 4-year cutting cycles are used, the planting density should be higher than 1111 stems ha(-1) (e.g., 1667 or 2500 stems ha(-1)). Based on the mean annual carbon storage for the plantation of 625 stems ha(-1), as an estimation, the mean carbon storage in the biomass of poplar plantations (excluding leaves) amounts to 3.75x10(7) t ha(-1)yr(-1) in China.
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81
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Du XL, Sun CC, Milam MR, Bodurka DC, Fang S. Ethnic differences in socioeconomic status, diagnosis, treatment, and survival among older women with epithelial ovarian cancer. Int J Gynecol Cancer 2007; 18:660-9. [PMID: 17892451 DOI: 10.1111/j.1525-1438.2007.01081.x] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
Abstract
The purpose of the study was to determine the ethnic disparities in socioeconomic status (SES) and in receiving definitive surgical treatment and adjuvant chemotherapy and to examine if these differences contribute to ethnic disparities in survival. We studied a population-based cohort of 5131 women diagnosed with epithelial ovarian cancer at age >or=65 between 1992 and 1999, identified from the Surveillance, Epidemiology and End Results-Medicare linked databases with up to 11 years of follow-up. The percentage of women diagnosed with epithelial ovarian cancer at advanced stage (stage III or IV) was 71.6% in Caucasians and 69.7% in African-Americans. Of these 4264 with stage IC-IV disease who are recommended for chemotherapy, fewer African-Americans received chemotherapy compared to Caucasians (50.2% versus 64.7%, P < 0.001). The risk of all-cause mortality in African-Americans was not significantly different from Caucasians (hazard ratio [HR] = 1.00, 95% CI = 0.88-1.13) after controlling for patient demographics, tumor characteristics, and comorbidity. The HR remained not significant in African-Americans compared to Caucasians after additionally adjusting for treatments (0.93, 0.82-1.06) or SES (0.94, 0.82-1.08) or both (0.88, 0.77-1.01). Women who underwent cancer-directed surgery and received adjuvant chemotherapy were 50% less likely to die than those who did not. The survival benefits from these therapies were similar in Caucasian and African-American women with ovarian cancer. There was no significant difference in survival between African-American and Caucasian women with ovarian cancer after adjusting for tumor characteristics, treatment, and sociodemographic factors. Although adjuvant chemotherapy was effective in prolonging survival, substantial numbers of women with ovarian cancer still did not receive chemotherapy.
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Fang S, Chan H, Chen W. Combination of linear and nonlinear methods on electroencephalogram state recognition. CONFERENCE PROCEEDINGS : ... ANNUAL INTERNATIONAL CONFERENCE OF THE IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. ANNUAL CONFERENCE 2007; 2005:4604-5. [PMID: 17281265 DOI: 10.1109/iembs.2005.1615495] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Abstract
Electroencephalogram EEG) reveals brain state, i.e. awake, sleep, rather than the content of thinking. We calculated fast/slow power spectrum ratio and approximate entropy on the EEG of three brain states, normal awake, sleep and coma. Based on the above EEG quantities, the EEG in different brain states can be clearly separated in the following way: (1) fast and complex for normal awake, (2) slow and complex for sleep and (3) slow and simple for coma.
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Lin M, Chan H, Fang S. Linear and nonlinear EEG indexes in relation to the severity of coma. CONFERENCE PROCEEDINGS : ... ANNUAL INTERNATIONAL CONFERENCE OF THE IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. ANNUAL CONFERENCE 2007; 2005:4580-3. [PMID: 17281259 DOI: 10.1109/iembs.2005.1615489] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Abstract
Glascow's coma scale (GCS) is a clinical standard for assessing the severity of coma in intensive care units (ICUs). The EEG monitoring can be on-line work, soon responds to the change in the brain wave, and allows long-term continuous monitoring of brain activity. In this paper, several EEG parameters, including spectral possession distribution and nonlinear description (approximate entropy and Lempel-Ziv complexity) were used to assess the capability of EEG indexes for the severity of coma. Our results demonstrated that all EEG parameters are moderately related to the GCS, with the Spearman statistical correlation of 0.62-0.71 between the spectral possession distribution and the GCS and 0.62-0.66 between nonlinear measures and the GCS. The moderate correlation between EEG parameters and the GCS implies the possibility of the EEG-derived index to reveal the neurological status of patients in coma.
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Hwang L, Williams M, Grimes C, Fang S, Oujesky B. High Hiv Incidence among Drug Users in Hepatitis B Vaccination Project from Inner City Neighborhoods. Am J Epidemiol 2006. [DOI: 10.1093/aje/163.suppl_11.s194-c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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85
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Abstract
Preterm intrauterine growth restriction (IUGR) is strongly associated with increased mortality and morbidity. In the management of these infants, complications of preterm birth can be amplified by the effect of suboptimal fetal growth. It is important that pregnancies with IUGR are detected before birth, so that delivery can be arranged in a high-risk maternity unit with the appropriate neonatal staff in attendance. The provision of full support for resuscitation and stabilisation of these infants is crucial to the short-term and long-term health of these infants, who have suffered chronic hypoxia and malnutrition in utero. The long term outcome studies of these infants are retrospective and they include SGA infants. The effects of prematurity affect the outcome of IUGR infants. IUGR is associated with cerebral palsy in those delivered more than 32 weeks gestation. Infants less than 32 weeks of gestation may have poor developmental outcome if the head growth is affected, these infants may have associated cognitive and behavioural problems. Children who fail to grow by 2-4 years are at risk of long term growth problems. This paper outlines the acute and long-term management of these infants.
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Onstad DW, Fang S, Voegtlin DJ. Forecasting seasonal population growth of Aphis glycines (Hemiptera: Aphididae) in soybean in Illinois. JOURNAL OF ECONOMIC ENTOMOLOGY 2005; 98:1157-62. [PMID: 16156566 DOI: 10.1603/0022-0493-98.4.1157] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
From 2001 to 2004, 252 fifty-plant samples were collected from commercial soybean, Glycine max L., fields in three townships (93-km2 area) in Illinois. Townships were sampled every 3 wk from late June or early July when aphids (Aphis glycines Matsumura) first invaded the townships to early August. We used linear regression of 18 mean township field densities to calibrate several simple models to predict the change in aphid population density in a township from one sampling date to the next. The best exponential model for the complete data set has an r2 = 0.54, Y2 = Ylexp (0.09659 x DAY), where Y1 and Y2 are the first and second samples of aphids separated by a 3-wk period (the number of days, DAY). Our intrinsic rate of increase for the population is much lower than rates calculated in other studies. The best single-variable linear model has an r2 = 0.88, Y2 = Y1 + 0.1084 x Y1 x DAY. The latter model indicates the value of including monitoring data in the prediction. The best two-variable model has an R2 = 0.98, Y2 = Y1 + 0.08136 x Y1 x DAY + 0.000080 x N1(2) x DAY, where N1(2) x DAY is the interaction term for initial, squared, sample density of the season multiplied by the number of days between samples. The latter two models indicate that the change in the population density is greater for more dense populations. Degree-days were generally inferior to days as the time component in the simple models.
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Fang S, Bagtharia R, Kumar R, Costeloe KL, Bush A, Millar MR, Adams GGW. Pneumatocoele and conjunctivitis in a newborn. Lancet 2004; 364:1610. [PMID: 15519631 DOI: 10.1016/s0140-6736(04)17314-5] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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88
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Abstract
The capacity for exquisite regulation of ubiquitylation provides eukaryotic cells with a means to fine-tune both protein function and levels. This complex set of processes affects myriad proteins and potentially impacts all cellular processes. Ubiquitylation is brought about through multienzyme processes, with specificity conferred primarily by interactions of substrates with specific ubiquitin protein ligases (E3s) in association with ubiquitin conjugating enzymes (E2s). Regulation of ubiquitylation occurs at multiple levels, including E2-E3 interactions, substrate recognition, chain elongation, binding of ubiquitin to conserved motifs and deubiquityation. This review presents the fundamentals of the ubiquitin conjugating system.
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Kang J, Li W, Wang X, Lin Y, Li X, Xiao X, Fang S. Gel polymer electrolytes based on a novel quaternary ammonium salt for dye-sensitized solar cells. J APPL ELECTROCHEM 2004. [DOI: 10.1023/b:jach.0000015622.11471.41] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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90
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Adams GGW, Clark BJ, Fang S, Hill M. Retinal haemorrhages in an infant following RetCam screening for retinopathy of prematurity. Eye (Lond) 2004; 18:652-3. [PMID: 14716332 DOI: 10.1038/sj.eye.6700728] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
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91
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Gu J, Wang R, Lin J, Fang S. Concentric sclerosis: imaging diagnosis and clinical analysis of 3 cases. Neurol India 2003; 51:528-30. [PMID: 14742939] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/28/2023]
Abstract
Baló's Concentric sclerosis (BCS) is a rare demyelinating disease considered to be a variant of multiple sclerosis (MS). The typical magnetic resonance imaging (MRI) changes associated with BCS consist of concentric rings or onions' cross-section on T1-weighted (T1W) images. Because MRI reveals pathological changes consistent with autopsy in the focus of BCS, it plays an important role in the before-death diagnosis of BCS. We report three cases of BCS diagnosed antemortem on the basis of the typical concentric rings pattern on MRI and on the basis of clinical findings and cerebrospinal fluid (CSF) examination. BCS often occurs in the prime of life, acutely or subacutely. Then come cerebral multifocal symptoms and signs. We find that BCS is not always an acute and irreversible pathological process as described in the past.
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Fang S, Ferrone M, Yang C, Jensen JP, Tiwari S, Weissman AM. The tumor autocrine motility factor receptor, gp78, is a ubiquitin protein ligase implicated in degradation from the endoplasmic reticulum. Proc Natl Acad Sci U S A 2001; 98:14422-7. [PMID: 11724934 PMCID: PMC64697 DOI: 10.1073/pnas.251401598] [Citation(s) in RCA: 340] [Impact Index Per Article: 14.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
gp78, also known as the tumor autocrine motility factor receptor, is a transmembrane protein whose expression is correlated with tumor metastasis. We establish that gp78 is a RING finger-dependent ubiquitin protein ligase (E3) of the endoplasmic reticulum (ER). Consistent with this, gp78 specifically recruits MmUBC7, a ubiquitin-conjugating enzyme (E2) implicated in ER-associated degradation (ERAD), through a region distinct from the RING finger. gp78 can target itself for proteasomal degradation in a RING finger- and MmUBC7-dependent manner. Importantly, gp78 can also mediate degradation of CD3-delta, a well-characterized ERAD substrate. In contrast, gp78 lacking an intact RING finger or its multiple membrane-spanning domains stabilizes CD3-delta. gp78 has thus been found to be an example of a mammalian cellular E3 intrinsic to the ER, suggesting a potential link between ubiquitylation, ERAD, and metastasis.
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Fang S, Kempley ST, Gamsu HR. Prediction of early tolerance to enteral feeding in preterm infants by measurement of superior mesenteric artery blood flow velocity. Arch Dis Child Fetal Neonatal Ed 2001; 85:F42-5. [PMID: 11420321 PMCID: PMC1721289 DOI: 10.1136/fn.85.1.f42] [Citation(s) in RCA: 60] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
AIMS To evaluate whether serial Doppler measurements of superior mesenteric artery (SMA) blood flow velocity after the first enteral feed could predict early tolerance to enteral feeding in preterm infants. METHODS When clinicians decided to start enteral feeds, Doppler ultrasound blood flow velocity in the SMA was determined before and after a test feed of 0.5 ml milk. The number of days taken for infants to tolerate full enteral feeding (150 ml/kg/day) was recorded. RESULTS Fourteen infants (group 1) achieved full enteral feeding within seven days. Thirty infants (group 2) took 8-30 days. There was no difference in the preprandial time averaged mean velocity (TAMV) between the groups at a median age of 3 (2-30) days. In group 1, there was a significant increase in TAMV (p<0.01) above the preprandial level at 45 and 60 minutes, but this did not occur in group 2. An increase in TAMV by more than 17% at 60 minutes has a sensitivity of 100% and a specificity of 70% for the prediction of early tolerance to enteral feeds. CONCLUSIONS There is a significant correlation between an increase in mean SMA blood flow velocity and early tolerance of enteral feeding. Doppler measurements of SMA blood flow velocity may be useful for deciding when to feed high risk preterm infants.
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Li Y, Cheng H, Fang S, Qian Z. [Prevalent forecast of kiwifruit bacterial canker caused by Pseudomonas syringae pv. actinidiae]. YING YONG SHENG TAI XUE BAO = THE JOURNAL OF APPLIED ECOLOGY 2001; 12:355-8. [PMID: 11758412] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/23/2023]
Abstract
The prevalent analysis of kiwifruit bacterial canker for several years showed that the effective ecological factors of severe degree were the precipitation (x1) in the second and last ten-days of March, and the average temperature (x2) of January. The model was y = 2.1359 + 0.0107x1 - 0.6061x2. The main factor of the prevalence was the relative variation of ten-days average temperature and precipitation in Winter and in early Spring, and the regression equation was y = -8.127 + 22.739x - 13.254x2. The forecast effect of the equation was obviously significant after testing.
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Li Y, Cheng H, Fang S, Qian Z. [Ecological factors affecting prevalence of kiwifruit bacterial canker and bacteriostatic action of bacteriocides on Pseudomonas syringae pv. actinidae]. YING YONG SHENG TAI XUE BAO = THE JOURNAL OF APPLIED ECOLOGY 2001; 12:359-62. [PMID: 11758413] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/23/2023]
Abstract
According to the systematic study for 5 years, this paper dealt with the ecological factors affecting prevalence of kiwifruit bacterial canker. The disease was more serious in the orchards with above 750 m in elevation, and more serious at mountain slope facing south than facing north. Incidence differed significantly among cultivars, with easy disease infection for Jinfeng, and strong disease resistance for Jinkui. The older the trees, the more the diseased plants. The one year old twigs had highest death twig incidence of diseased twigs and death twig incidence than other twigs. Among 6 tested bacteriocides, Jiaruinong and streptomycin showed best bacteriostatic effect.
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Fang S, Yu J, Feng J, Han C, Li D, Liu Y. Identification of rice black-streaked dwarf fijivirus in maize with rough dwarf disease in China. Arch Virol 2001; 146:167-70. [PMID: 11266211 DOI: 10.1007/s007050170200] [Citation(s) in RCA: 74] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Three virus isolates from maize with rough dwarf in different provinces in China were analyzed at the molecular level. When compared to an isolate from diseased rice plants in Hubei Province, all four isolates had identical genomic RNA electrophoretic profiles, which were composed of ten double-stranded (ds) RNAs. Full-length cDNAs of segment 10 (S10) from each of the four isolates were cloned by RT-PCR and the complete sequences were determined. Analysis of the sequences revealed that each consisted of 1801 nucleotides and contained a single open reading frame (ORF) which potentially encoded a protein with 558 amino acids. Further, the sequences showed more than 97.0% and 98.0% identity at nucleotide and amino acid levels, respectively. In addition, their identities to rice black-streaked dwarf virus S10 were significantly higher than those to maize rough dwarf virus S10. Based on these results, it is suggested that the virus which causes this maize disease in China is rice black-streaked dwarf virus.
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Phillips CL, Arend LJ, Filson AJ, Kojetin DJ, Clendenon JL, Fang S, Dunn KW. Three-dimensional imaging of embryonic mouse kidney by two-photon microscopy. THE AMERICAN JOURNAL OF PATHOLOGY 2001; 158:49-55. [PMID: 11141478 PMCID: PMC1850252 DOI: 10.1016/s0002-9440(10)63943-0] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 09/21/2000] [Indexed: 11/17/2022]
Abstract
Developing mammalian embryonic kidney becomes progressively more elaborate as the ureteric bud branches into undifferentiated mesenchyme. Morphological perturbations of nephrogenesis, such as those seen in inherited renal diseases or induced in transgenic animals, require careful and often tedious documentation by multiple methodologies. We have applied a relatively quick and simple approach combining two-photon microscopy and advanced three-dimensional (3-D) imaging techniques to visualize and evaluate these complex events. As compared with laser confocal microscopy, two-photon microscopy offers superior optical sectioning deep into biological tissues, permitting analysis of large, heterogeneous, 3-D structures such as developing mouse kidney. Embryonic and newborn mouse kidneys were fluorescently labeled with lectins, phalloidin, or antibody. Three-dimensional image volumes were then collected. The resulting volume data sets were processed using a novel 3-D visualization technique. Reconstructed image volumes demonstrate the dichotomous branching of ureteric bud as it progresses from a simple, symmetrical structure into an elaborate, asymmetrical collecting system of multiple branches. Detailed morphology of in situ cysts was elucidated in a transgene-induced mouse model of polycystic kidney disease. We expect this integration of two-photon microscopy with advanced 3-D image analysis will provide a powerful tool for illuminating a variety of complex developmental processes in multiple dimensions.
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Sumanasekera GU, Adu CK, Fang S, Eklund PC. Effects of gas adsorption and collisions on electrical transport in single-walled carbon nanotubes. PHYSICAL REVIEW LETTERS 2000; 85:1096-1099. [PMID: 10991483 DOI: 10.1103/physrevlett.85.1096] [Citation(s) in RCA: 69] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/02/2000] [Indexed: 05/23/2023]
Abstract
Degassing of bundles of single-walled carbon nanotubes in vacuum at 500 K is found to drive the thermoelectricpower (TEP) strongly negative, indicating that the degassed metallic tubes in a bundle are n type. The magnitude of the negative TEP indicates that important asymmetry in the electronic carbon pi bands exists near the Fermi energy. Easily measurable increases in the TEP ( approximately 5-10 &mgr;V/K) and resistivity ( 2%-10%) are observed at 500 K upon exposure to N2 and He, suggesting that even gas collisions with the nanotube wall can contribute significantly to the transport properties.
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