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991.
992.
This article presents data from 861 men who have participated in 14 separate occupational studies on testicular function. This population represents the largest series taken from occupational studies. The mean and median sperm counts were 107.1 and 83.0 million/ml of semen, respectively. The percentage of men with sperm counts less than 20 million/ml of semen was 8.7%. No significant differences were noted for age or race. A major issue in occupational studies requiring semen samples is how to successfully recruit the target population to participate. The number of semen samples requested can influence willingness to participate. Data from 137 men, each with three separate sperm counts, indicate that a single sample will suffice for an occupational study. 相似文献
993.
Role of venous drainage in cerebral arteriovenous malformation surgery,as related to the development of postoperative hyperperfusion injury 总被引:2,自引:0,他引:2
OBJECTIVE: To elucidate the role of venous drainage in cerebral arteriovenous malformation (AVM) surgery, with respect to the development of postoperative hyperperfusion injury. METHODS: For 52 patients with supratentorial AVMs, cortical capillary oxygenation (SaO(2)) was assessed intraoperatively, before and after resection, in the vicinity of the AVMs, by using a microspectrophotometric method. Assessed areas were defined as being related to feeding arteries or draining veins or as distant areas. Patients were divided into three groups on the basis of postoperative angiographic findings, as follows: Group 1, all former draining veins preserved (8 patients); Group 2, > or =1 former draining vein visible (12 patients); Group 3, no former draining veins visible (32 patients). Patients and SaO(2) values were pooled and compared by using paired and unpaired t tests (P < 0.05). Venous circulation times were calculated from digital subtraction angiography films. RESULTS: The postresectional relative increases in SaO(2) values were highest in draining vein areas (+40.8%, compared with +25% in feeder areas and +25.5% in distant areas). Five postoperative hyperemic complications occurred (9.6%), none in Group 1 (with all draining veins preserved), two (16.7%) in Group 2, and three (9.4%) in Group 3 (with all draining veins occluded). The lowest preresectional SaO(2) values (31.7 +/- 6.2%) were measured in the drainer areas of the five patients who subsequently developed hyperperfusion injuries. Among those patients, postresectional increases in SaO(2) values were significantly greater in drainer areas (+167.8%) than in feeder areas (+28.3%) or distant areas (+25.8%). Postoperative venous circulation times in former draining veins in Group 2 were significantly greater than those in Group 1 (8.9 +/- 1.5 s versus 6.3 +/- 0.6 s). Circulation times in normal veins in the five patients with hyperperfusion injury increased from 5.6 +/- 1.0 seconds (preoperatively) to 8.4 +/- 1.9 seconds (postoperatively). CONCLUSION: Postoperative hyperperfusion injury after resection of cerebral AVMs can be explained on the basis of unconstrained arterial inflow into cortical areas, which are rendered hypoxic/ischemic by longstanding preoperative venous hypertension. The risk for postoperative breakthrough complications seems higher in the presence of multiple draining veins, which also participate in the physiological venous drainage system of the ipsilateral hemisphere. 相似文献
994.
A 40-year-old woman with complaints of relapse in the upper abdomen and dysphagia was referred for laparascopic hiatal hernia repair. Chest radiograph, barium-swallow, and upper endoscopy revealed a paraesophageal hernia. Esophageal manometry and 24-h-pH study showed no pathological findings. A laparoscopic gastropexy was planned. Intraoperatively, in contradiction to the preoperative findings, an extrahiatal hernia containing most of the stomach was found. After resection of the hernia sac, the beating heart without covering pericardium was seen. These findings were confirmed by an additional thoracoscopy at the end of the operation. The defect was closed by direct suturing. The postoperative course and 2-month follow-up were uneventful. The resected parts of the hernia sac showed an embryonic and dysgenetic etiology. This rare malformation has been reported in combination with complex syndromes, which appear with serious clinical and morphological signs in the neonatal period. In adults, the pericardial aplasia can be observed during diagnostic or surgical interventions. In these patients, complaints are usually not caused by the malformation but may be due to the occasional herniation of abdominal organs. We consider laparoscopic repair to be a gentle and safe procedure for the treatment of extrahiatal hernias. 相似文献
995.
Human connective tissue growth factor mRNA expression of epiretinal and subretinal fibrovascular membranes: a report of three cases 总被引:12,自引:0,他引:12
Meyer P Wunderlich K Kain HL Prünte C Flammer J 《Ophthalmologica. Journal international d'ophtalmologie. International journal of ophthalmology. Zeitschrift für Augenheilkunde》2002,216(4):284-291
PURPOSE: To investigate the correlation between connective tissue growth factor (CTGF) mRNA expression and immunohistochemical characteristics (expression of type I collagen and tenascin) of fibrovascular membranes of proliferative retinal diseases under in vivo conditions. METHODS: CTGF mRNA expression was investigated using in situ hybridization. Expression of type I collagen and tenascin was detected by immunohistochemical staining. RESULTS: CTGF mRNA is produced in transformed retinal pigment epithelial cells and appears also in fibroblast-like cells, which are embedded in epiretinal and subretinal membranes of proliferative retinal diseases as well as in surgically removed subretinal membranes. In all examined membranes, expression of human CTGF mRNA appears in concurrence with the expression of type I collagen and tenascin. CONCLUSIONS: The predominant expression of CTGF mRNA in the development of fibrovascular membranes of proliferative retinal diseases suggests a significant role of CTGF in the pathological course of these ocular disorders. 相似文献
996.
997.
D'hermies F Morel X Meyer A Dighiero P Ellies P Fayet B Assaraf E Halhal M Bonnet M Behar-Cohen F Renard G 《Journal fran?ais d'ophtalmologie》2002,25(8):863-866
Among corneal dystrophies, the keratoconus is one of the most frequently observed among young adults. A clinico pathological case is reported in a 13-year-old-girl of African origin. The diagnosis of bilateral keratoconus was established based on the obvious changes of the corneal curvature and thickness. After an unsuccessful attempt to improve vision with contact lenses, a keratoplasty was finally performed on one side to remove the pathological cornea. Its histopathological study found the characteristic changes of keratoconus: breaks of Bowman's layer and corneal thinning. 相似文献
998.
Meyer JH Goulding VS Wilson AA Hussey D Christensen BK Houle S 《Psychopharmacology》2002,163(1):102-105
RATIONALE: Bupropion is thought to treat major depression by blocking the dopamine transporter (DAT) because bupropion appears to have a selective affinity for the DAT. The validity of this mechanism has been questioned because the affinity of bupropion for the DAT is quite low. OBJECTIVE: To determine the occupancy of bupropion for the DAT during clinical treatment of patients with depression. METHODS: Positron emission tomography with [(11)C]-RTI32 was used to determine the striatal DAT binding potential (BP) of eight depressed patients before and during treatment with bupropion. BP is proportional to available receptor density (receptors not blocked by drug). Occupancy is the percent change in BP. Eight healthy subjects were similarly studied in a test-retest design. RESULTS: No significant difference in DAT BP was found after bupropion treatment in comparison to the test-retest data. The occupancy after bupropion treatment was 14% (confidence interval 6-22%) as compared to 7% in the test-retest condition. CONCLUSIONS: Bupropion treatment occupies less than 22% of DAT sites. This raises the question as to whether a DAT occupancy of less than 22% is therapeutic or whether there is another mechanism involved during treatment with bupropion. 相似文献
999.
Pharmacodynamic interaction between the new selective cholesterol absorption inhibitor ezetimibe and simvastatin 总被引:5,自引:0,他引:5
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Kosoglou T Meyer I Veltri EP Statkevich P Yang B Zhu Y Mellars L Maxwell SE Patrick JE Cutler DL Batra VK Affrime MB 《British journal of clinical pharmacology》2002,54(3):309-319
AIMS: The primary aims of these two single-centre, randomized, evaluator-blind, placebo/positive-controlled, parallel-group studies were to evaluate the potential for pharmacodynamic and pharmacokinetic interaction between ezetimibe 0.25, 1, or 10 mg and simvastatin 10 mg (Study 1), and a pharmacodynamic interaction between ezetimibe 10 mg and simvastatin 20 mg (Study 2). Evaluation of the tolerance of the coadministration of ezetimibe and simvastatin was a secondary objective. METHODS: Eighty-two healthy men with low-density lipoprotein cholesterol (LDL-C) >or=130 mg dl-1 received study drug once daily in the morning for 14 days. In Study 1 (n=58), five groups of 11-12 subjects received simvastatin 10 mg alone, or with ezetimibe 0.25, 1, or 10 mg or placebo. In Study 2 (n=24), three groups of eight subjects received simvastatin 20 mg alone, ezetimibe 10 mg alone, or the combination. Blood samples were collected to measure serum lipids in both studies. Steady-state pharmacokinetics of simvastatin and its beta-hydroxy metabolite were evaluated in Study 1 only. RESULTS: In both studies, reported side-effects were generally mild, nonspecific, and similar among treatment groups. In Study 1, there were no indications of pharmacokinetic interactions between simvastatin and ezetimibe. All active treatments caused statistically significant (P<0.01) decreases in LDL-C concentration vs placebo from baseline to day 14. The coadministration of ezetimibe and simvastatin caused a dose-dependent reduction in LDL-C and total cholesterol, with no apparent effect on high-density lipoprotein cholesterol (HDL-C) or triglycerides. The coadministration of ezetimibe 10 mg and simvastatin 10 mg or 20 mg caused a statistically (P<0.01) greater percentage reduction (mean -17%, 95% CI -27.7, -6.2, and -18%, -28.4, -7.4, respectively) in LDL-C than simvastatin alone. CONCLUSIONS: The coadministration of ezetimibe at doses up to 10 mg with simvastatin 10 or 20 mg daily was well tolerated and caused a significant additive reduction in LDL-C compared with simvastatin alone. Additional clinical studies to assess the efficacy and safety of coadministration of ezetimibe and simvastatin are warranted. 相似文献
1000.
Surveillance data on occupational audiological disorders have been collected by the Occupational Surveillance Scheme for Audiological Physicians (OSSA) since October 1997 and by the Occupational Physicians Reporting Activity (OPRA) from January 1996. During the 3 years ending in September 2000, a total of 1620 new cases were received from consultant audiological physicians; 988 new cases were estimated from reports by occupational physicians in the period from October 1997 to September 2000. The annual incidence of occupational noise-induced hearing loss (NIHL) was 1.94 and 1.23 per 100 000 workers for the OSSA and OPRA schemes, respectively. The median age at diagnosis with NIHL was 59 years in OSSA reports and 50 years in OPRA; nearly all cases were seen in men (95.6 and 92.5% male cases for OSSA and OPRA, respectively). High incidence rates based on OSSA reports were seen in foundry labourers (64.0 per 100 000 employed), coal gas and coke oven furnace workers (54.6), workers in transport and communication (43.1), metal workers (31.3), and members of the armed forces (28.3). Data from occupational physicians point to high rates in sawyers and woodworking machinists, metal furnace workers, coach and carriage builders, maintenance fitters, and engineering labourers. Among workers aged < or =45 years, those in manufacturing and the armed forces were prominent. The long latency of occupational hearing loss makes surveillance difficult, but consistent patterns in occupational risk suggest targets for preventive efforts. 相似文献