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41.
Internet网上细胞凋亡研究的信息资源及其利用 总被引:1,自引:0,他引:1
0 引言 Internet网上含有丰富的信息资源 ,科研人员可以通过 Internet网了解其所研究领域的最新发展动态 ,获取全面和系统的科研信息 ,有利于进行学术交流[1 ] .然而网上信息浩如烟海 ,当检索某一专门领域的资料时 ,有时无从下手 .我们在科研实践中对 Internet网上主要的细胞凋亡研究信息资源及其查找方法进行了归纳 .1 细胞凋亡专业网站1. 1 The Cell death society (http:/ / www.celldeath-apoptosis.org) 为美国细胞死亡学会主办 ,概括了细胞凋亡和程序性细胞死亡研究的各个领域 ,包括与细胞凋亡有关的各种疾病 .可以免费注册… 相似文献
42.
Marigo FA Esaki K Finger PT Ishikawa H Greenfield DS Liebmann JM Ritch R 《Ophthalmology》1999,106(11):2131-2135
BACKGROUND: To describe the ultrasound biomicroscopic (UBM) features of anterior segment cysts. DESIGN: A retrospective case series. PARTICIPANTS: One hundred eighteen eyes with anterior segment cysts examined by UBM at The New York Eye and Ear Infirmary between August 1992 and November 1997 were included in this study. INTERVENTION: The authors reviewed demographic and diagnostic data from the medical record including ocular and medical history, age, race, gender, and intraocular pressure. Ultrasound data concerning the type, number, position, and acoustic characteristics of cysts were recorded. The authors then correlated the written, clinical, and UBM characteristics. RESULTS: One hundred eyes (92.6%) had neuroepithelial cysts. Ninety (83.3%) of these had primary neuroepithelial cysts, 10 (9.3%) had cysts associated with uveitis, 7 (6.5%) had implantation cysts, and 1 (0.9%) had a cavitated ciliary body tumor. Neuroepithelial cysts typically were round or ovoid, thin-walled, and echolucent. Of the 90 eyes with primary neuroepithelial cysts, 56 (62.2%) had 3 or fewer cysts; multiple cysts (>3 per eye) were found in 34 eyes (37.8%). The multiple cysts occupied more than 180 degrees in 12 patients (13.3%). Primary neuroepithelial cysts were located at the iridociliary junction (74.2%), pars plicata (14.0%), pars plana (6.8%), and iris (5.0%). Implantation cysts (seven eyes) tended to have thicker walls and two contained a copious, echogenic material. CONCLUSION: The UBM results provide important information regarding location and extent of anterior segment cystic lesions. Ultrasound characteristics may help differentiate between neuroepithelial, implantation, and neoplastic cysts. 相似文献
43.
Increasing sampling density improves reproducibility of optical coherence tomography measurements. 总被引:1,自引:0,他引:1
R Gurses-Ozden H Ishikawa S T Hoh J M Liebmann A Mistlberger D S Greenfield H L Dou R Ritch 《Journal of glaucoma》1999,8(4):238-241
PURPOSE: Published series of peripapillary retinal nerve fiber layer (RNFL) measurements using optical coherence tomography (OCT) have sampled 100 evenly distributed points on a 360 degrees peripapillary circular scan. The goal of this study was to determine whether a four-fold increase in sampling density improves the reproducibility of OCT measurements. METHODS: Complete ophthalmic examinations, achromatic automated perimetry, and OCT imaging were performed in all patients. The OCT scanning consisted of three superior and inferior quadrantic scans (100 sampling points/quadrant) and three circular scans (25 points/quadrant). The RNFL thickness measurements and coefficient of variation (CV) were calculated for the superior and inferior quadrants for each sampling density technique. RESULTS: The study included 22 eyes of 22 patients (3 control subjects; 2 patients with ocular hypertension; and 17 patients with glaucoma). Quadrants with associated glaucomatous visual field loss on automated achromatic perimetry had thinner RNFLs than quadrants without functional defects for both the 25- and 100-points/quadrant scans. For quadrants associated with normal visual hemifields (n = 22), there was no difference between the 25- and 100-points/quadrant scans in mean RNFL thickness and CV. Among quadrants with visual field defects (n = 22), RNFL thickness measurements were thinner in the 25-points/quadrant scans than in the 100-points/quadrant scans. The CV for the 25-points/quadrant scans (25.9%) was significantly higher than that for the 100-points/quadrant scans (11.9%). CONCLUSION: Increasing the sampling density of OCT scans provides less variable representation of RNFL thickness. The optimal sampling density to achieve maximal reliability of OCT scans remains to be determined. 相似文献
44.
Beer drinking accounts for most of the hazardous alcohol consumption reported in the United States 总被引:5,自引:0,他引:5
OBJECTIVE: Patterns and correlates of hazardous drinking, defined as occasions in which five or more drinks were consumed in a day, were compared for wine, beer and distilled spirits. METHOD: From a probability sample of the U.S. adult household population, 2,817 respondents who had consumed at least one drink in the previous year were selected for analysis. RESULTS: The results show that, in the U.S., beer accounts for the bulk of alcohol consumed by the heaviest drinkers. Beer also accounts for a disproportionate share of hazardous drinking. Logistic regression analyses revealed that drinkers who consume beer in a hazardous fashion at least monthly are more likely to be young, male and unmarried, and less likely to be black than are other drinkers. Hazardous beer consumption is more predictive of alcohol-related problems than hazardous consumption of wine or spirits. CONCLUSIONS: Three potential explanations for the results are considered: advertising, beer-drinking subcultures and risk compensation. Additional research is urged in order to better specify the causal role of these and other factors in hazardous beer drinking. 相似文献
45.
46.
Studies of diabetic polyneuropathy using conduction velocity distribution (DCV) analysis 总被引:5,自引:0,他引:5
L J Dorfman K L Cummins G M Reaven J Ceranski M S Greenfield L Doberne 《Neurology》1983,33(6):773-779
The distributions of nerve fiber conduction velocities (DCVs) derived from the median nerves of 29 adult diabetic patients (mean age, 52.1 +/- 12.3 years) with mild or no symptoms or signs of polyneuropathy were compared with DCVs from 34 age-appropriate normal subjects. Ten patients (34%) had normal findings (type A DCVs). In the 19 patients (66%) with abnormal DCVs, defined as 10% or more of the DCV area falling outside the normal 95% confidence limits, two distinct patterns of DCV alteration were observed: type B DCVs (11 patients) showed reduced DCVmax, DCVmean, and DCVpeak, together with reduced DCVrange (narrow profile); whereas type C DCVs (8 patients) had reduced DCVmax, DCVmean, DCVpeak, and DCVmin, with normal DCVrange (broad profile). It is proposed that type C DCV represents a more advanced form of type B and that both reflect selective dysfunction of the fastest conducting (presumably largest-diameter) fibers in the nerve trunk. DCVmax was consistently greater than conventional measures of "maximal" CV in all patient subgroups. Patients with abnormal DCVs had higher incidence of mild neuropathic symptoms (15 of 19 versus 4 of 10, p less than 0.01) and greater insulin dependence (11 of 19 versus 1 of 10, p less than 0.001). Serial studies in 10 patients showed, at most, small degrees of change in conduction properties over relatively short intervals (1 to 9 months). 相似文献
47.
During a period of six years 7,555 bovine sera, 421 canine sera, 251 porcine sera and 135 equine sera were tested for agglutinins to Leptospira interrogans serotypes canicola, grippotyphosa, hardjo, icterohemorrhagiae, pomona and sejroe. The bovine sera reacted predominantly with hardjo and/or sejroe at a rate of 15% compared to 3.5% with pomona. Breeding or abortion problems were associated with pomona but not with sejroe/hardjo agglutinins. The canine sera reacted to canicola (9.9%y and icterohemorrhagiae (5.4%), tcted predominantly with canicola (8.9%) and icterohemorrhagiae (8.1%). 相似文献
48.
Greenfield SF Reizes JM Muenz LR Kopans B Kozloff RC Jacobs DG 《The American journal of psychiatry》2000,157(11):1867-1869
OBJECTIVE: Characteristics of the subsequent treatment received by people who screened positive for depression in the 1996 National Depression Screening Day were investigated. METHOD: A follow-up telephone survey was completed by 1,502 randomly selected participants from 2,800 sites. RESULTS: Of 927 people for whom additional evaluation was recommended, 602 (64.9%) obtained evaluations and 503 (83.6%) received treatment. Of these 503, 260 (51.7%) received psychotherapy and medication, 130 (25.8%) received medication only, and 93 (18.5%) received psychotherapy only. Compared with people without health or mental health insurance, individuals with health insurance (66.7% versus 57.5%) and mental health insurance (74.6% versus 55.3%) were more likely to comply with the recommendation to obtain follow-up evaluation. CONCLUSIONS: One-half of the people treated for depression received a combination of psychotherapy and medication. Lack of insurance was associated with not following the recommendation to obtain further evaluation and treatment. 相似文献
49.
Greenfield LJ Proctor MC Michaels AJ Taheri PA 《Journal of vascular surgery》2000,32(3):490-5; discussion 496-7
OBJECTIVE: The purpose of this study was to describe outcomes for patients with trauma who had vena caval filters placed in the absence of venous thromboembolic disease (group P) and compare them with outcomes for patients with trauma who had filters placed after either deep venous thrombosis or pulmonary embolism (group T). DESIGN: The study is a case series of consecutive patients who received vena caval filters after traumatic injury. Data were collected prospectively at the time of filter placement from reports of diagnostic studies obtained for clinical indications and during the annual follow-up examinations. Event rate findings are based on objective tests. Data were obtained from the Michigan Vena Cava Filter Registry. RESULTS: Filters were placed in 385 patients with trauma; 249 of these filters were prophylactic (group P). Event rates were similar in the two groups. New pulmonary embolism was diagnosed in 1.5% of the patients in group P and 2% of the patients in group T. Caval occlusion rates were 3.5% for group P and 2.3% for group T. In all, 15.6% of the patients in group P had deep venous thrombosis or pulmonary embolism after placement. The frequencies of lower extremity swelling and use of support hose were higher in group T than in group P (43% vs 25% and 25% vs 3.5%, respectively; P <.005). Outcomes were comparable in the two groups with respect to mechanical stability of the filter. CONCLUSIONS: The prophylactic indication for vena caval filter placement in patients with trauma is associated with a low incidence of adverse outcomes while providing protection from fatal pulmonary embolism. The current challenge is to limit the number of unnecessary placements through improved methods of risk stratification. 相似文献
50.