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1.
Hysterosalpingography was performed in 31 patients by means of a low-dose scanning-beam digital radiographic system. The technique permits adequate evaluation of gynecologic abnormalities while allowing significant reduction in radiation: 2.4-mR (6.1 X 10(-7) C/kg) exposure to the skin and 0.7-mrad (7 X 10(-6) Gy) mean dose to the ovaries per image obtained. Sixteen patients demonstrated readily recognizable and documented abnormalities, corroborated by laparoscopy, laparotomy, or other supportive evidence. 相似文献
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F. R. VOGELPOEL R. J. VAN KOOIJ E. R. TE VELDE J. VERHOEF 《International journal of andrology》1990,13(2):81-86
Isolated sperm from normo-, oligo- and astheno-spermic men were incubated for 20 h in medium supplemented with 8% heat-inactivated or untreated human serum, and in medium with heated or untreated serum deficient in complement factor C3. Before and after incubation, sperm motility was assessed by means of a computer-assisted semen analyser. The results did not show significant differences between the motility of sperm incubated in heated or untreated serum. It is concluded that heating of homologous serum is not necessary for preserving sperm motility and in some cases may even be disadvantageous. 相似文献
4.
Flexible fiberoptic gastrointestinal endoscopy has greatly simplified the diagnosis and treatment of colonic volvulus. The management of 39 patients with colonic volvulus treated over 9 years was reviewed. Five per cent were treated with rectal tube decompression alone, 23% were treated with either sigmoidoscopic or colonoscopic reduction, and 26% were treated exclusively with operation. Endoscopic reduction was attempted in nearly half of the patients in preparation for operation. Recurrent volvulus occurred in 57% of patients initially treated with endoscopic reduction alone. Sigmoidoscopic examination did not confirm the diagnosis in 24% of instances in which it was used, although colonoscopy was always diagnostic. The overall mortality rate was 8%, but increased to 25% in patients with gangrene of the colon. Three patients who later proved to have gangrene of the colon had a normal initial sigmoidoscopic examination. Two of these patients died of intra-abdominal sepsis from a perforated colon. In five patients an accurate endoscopic diagnosis of gangrene prompted immediate exploration. None of these patients died. Endoscopy is a safe and effective diagnostic tool for the initial evaluation of patients with suspected colon volvulus. In addition, endoscopy may result in therapeutic decompression and may provide visual assessment of the viability of the bowel mucosa, thus assisting in the timing of appropriate operative treatment. 相似文献
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Image-directed percutaneous biopsies with a biopsy gun 总被引:3,自引:0,他引:3
Core tissue for histologic study is believed by many pathologists to be more diagnostic than material from needle aspiration. Recently, a biopsy "gun" has been introduced, which simplifies core biopsies. With this device, 182 biopsies of multiple anatomic sites were performed with ultrasonic, computed tomographic, and fluoroscopic guidance and 18-gauge needles. High-quality histopathologic specimens were obtained in 177 of the biopsies, and diagnostic target tissue was obtained in 167. Only three significant complications occurred: one bleeding complication that required transfusion and two cases of pneumothorax that necessitated placement of chest tubes. The biopsy gun eliminated the disjointed movements of conventional "skinny" needle biopsies, and none of the samples demonstrated significant "crush" artifact or obscuring blood, problems that are commonly associated with manual biopsy techniques. Patient discomfort was decreased with this system compared with that of manual biopsies, and the total procedure time was reduced. Because of these distinct advantages, the authors now use the biopsy gun exclusively for all percutaneous biopsies and recommend that other institutions consider the use of this biopsy method. 相似文献
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目的观察去甲硫氨酸全肠外营养对大鼠血清氨基酸谱等的影响.方法 Wistar大鼠24只,随机分为含甲硫氨酸(+MetTPN,n=12)和去甲硫氨酸全肠外营养2组(-MetTPN,n=12),分别给予相应的TPN支持.治疗7d后,每组随机抽取6只大鼠处死,检测血清FAA(HPLC法)、肝肾功能和全血常规,同时作心、肺、肝、肾组织病理学检查.两组其余大鼠继续原TPN治疗,观察生存期.结果 -MetTPN组大鼠血清游离Met、Cys明显降低,Asp、Glu、Ser等显著增高;大鼠体重下降;血清总蛋白和白蛋白水平下降;血常规和肾功能未见明显异常;组织学检查见肝细胞轻度肿胀,细胞核仁增粗,心肺肾未见明显异常;平均生存18d.对照组上述检查未见异常,除一只大鼠因导管并发症于TPN第16d死亡,其余大鼠全部存活.结论 -MetTPN一周可致大鼠血清游离Met、Cys明显降低和Asp、Glu、Ser等显著增高,及轻度肝功能改变;随着-MetTPN时间延长,出现严重的代谢紊乱和器官功能障碍导致死亡. 相似文献
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Methods for evaluation of retinal microvascular abnormalities associated with hypertension/sclerosis in the Atherosclerosis Risk in Communities Study 总被引:13,自引:0,他引:13
Hubbard LD Brothers RJ King WN Clegg LX Klein R Cooper LS Sharrett AR Davis MD Cai J 《Ophthalmology》1999,106(12):2269-2280
OBJECTIVE: To develop protocols to photograph and evaluate retinal vascular abnormalities in the Atherosclerosis Risk in Communities (ARIC) Study; to test reproducibility of the grading system; and to explore the relationship of these microvascular changes with blood pressure. DESIGN: Population-based, cross-sectional study. PARTICIPANTS: Among 4 examination centers, 11,114 participants (48-73 years of age) at their third triennial examination, after excluding persons with diabetes from this analysis. METHODS: One eye of each participant was photographed by technicians with nonmydriatic fundus cameras. Reading center graders evaluated focal arteriolar narrowing, arteriovenous (AV) nicking, and retinopathy by examining slides on a light box and measured diameters of all vessels in a zone surrounding the optic disc on enhanced digitized images. To gauge generalized narrowing, vessel diameters were combined into central arteriolar and venular equivalents with formulas adjusting for branching, and the ratio of equivalents (A/V ratio) was calculated. MAIN OUTCOME MEASURES: Retinal vascular abnormalities, mean arteriolar blood pressure (MABP). RESULTS: Among 11,114 participants, photographs were obtained of 99%, with quality sufficient to perform retinal evaluations in 81%. In the 9040 subjects with usable photographs, A/V ratio (lower values indicate generalized arteriolar narrowing) ranged from 0.57 to 1.22 (median = 0.84, interquartile range = 0.10), focal arteriolar narrowing was found in 7%, AV nicking in 6%, and retinopathy in 4%. Because of attrition of subjects and limitation of methods, prevalence of abnormality was likely underestimated. Controlling for gender, race, age, and smoking status, these retinal changes were associated with higher blood pressure. For every 10-mmHg increase in MABP, A/V ratio decreased by 0.02 unit (P < 0.0001), focal arteriolar narrowing had an odds ratio (OR) of 2.00 (95% confidence interval [CI] = 1.87-2.14), AV nicking had an OR of 1.25 (95% CI = 1.16-1.34), and retinopathy had an OR of 1.25 (95% CI = 1.15-1.37). For any degree of generalized narrowing, individuals with focal narrowing had MABP approximately 8 mmHg higher than those without (P < 0.0001). Masked replicate assessment of a sample found the following reproducibility: for A/V ratio, correlation coefficient = 0.79 and median absolute difference = 0.03; for focal arteriolar narrowing, kappa = 0.45; for AV nicking, kappa = 0.61; and for retinopathy, kappa = 0.89. CONCLUSION: Protocols have been developed for nonmydriatic fundus photography and for evaluation of retinal vascular abnormalities. Several microvascular changes were significantly associated with higher blood pressure; follow-up will show whether these are predictive of later cerebrovascular or cardiovascular disease independently of other known risk factors. 相似文献
9.
Annette J. Stark Ph.D. Gloria M. Gutman Ph.D. Kent Brothers Ph.D. 《Journal of community health》1982,8(2):102-109
This paper addresses the question of the degree of agreement between experienced assessors making level-of-care placement decisions for the same client, given a comparable opportunity to obtain and record client information in a community-based Long-Term Care program.A systematic sample of 246 cases was selected, consisting of 47 preadmission assessments and 199 reviews. The resulting data were subjected to analysis using the statistic Kappa and the degree of agreement categories suggested by Fleiss.1 It was found that at the level-of-care extremes— Extended Care and Personal Care—the agreement between two nurse assessors for reviews could be considered excellent. In the Intermediate Care range, however, the reliability of the level-of-care decision can only be considered fair. Agreement for initial assessments was less, withK=0.469 indicating, overall, only fair agreement. While there was most often only a one-care-level difference between assessors, the program assessor tended to recommend a higher level than the study or check assessor. This has implications for funding agencies and/or facility planners who must assess the likely care requirements of an increasing number of disabled elderly. From a program management perspective, the preceding analyses allow an objective judgement of the extent of the placement decision problem, if any, and further provide a definition of areas most in need of revision. The value of collaboration between practitioner and researcher is evident in these analyses.Dr. Stark is Director, Division of Health Services Research and Development and Assistant Professor, Department of Health Care and Epidemiology, The University of British Columbia. Dr. Gutman is Director, Gerontology Centre and Associate Professor, Faculty of Interdisciplinary Studies, Simon Fraser University. Dr. Brothers is Research Associate, Division of Health Systems, The University of British Columbia. Address enquiries to Dr. A. Stark, Director, Division of Health Services Research and Development, Office of the Coordinator of Health Sciences, The John F. McCreary Health Sciences Centre, 2194 Health Sciences Mall, The University of British Columbia, Vancouver, B.C., V6T 1Z6.The research described in this paper, as well as the larger study of which it is a part, is supported by a grant from the B.C. Health Care Research Foundation. In addition, the cooperation and support of the Ministry of Health, Province of British Columbia is gratefully acknowledged. 相似文献
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