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121.
ROBERT H. SHAPIRO CHARLES H. MULLER GREGORY CHEN RICHARD E. BERGER 《The Journal of urology》1998,160(4):1341-1346
Purpose
Reactive oxygen species, which are primarily produced by leukocytes, are generally detrimental to sperm. High reactive oxygen species levels are found in men with abnormal sperm function. Since men often have poor sperm characteristics and infertility after vasectomy reversal, fertile men to determine if reactive oxygen species were elevated in the former group.Materials and Methods
We studied semen samples of men with proved fertility (39) and those with previously proved fertility who had undergone vasectomy reversal (45). The presence of leukocytes was determined by Bryan-Leishman staining. Reactive oxygen species endogenous activity was monitored by luminol dependent chemiluminescence in washed cells, including all cells in the semen, and Percoll density gradient purified sperm.Results
After vasovasostomy men had significantly lower sperm concentration, motility and computerized motility measurements than fertile men. Mean reactive oxygen species in washed seminal cells after vasovasostomy was 684 relative light units per second compared to 49 for fertile controls (p <0.0001). Density gradient purified sperm had 53 and 0.64 relative light units per second, respectively (p <0.0001). When men with leukocytospermia were excluded from analysis, differences between the groups remained, although 9 times more reactive oxygen species were detected in men after vasectomy reversal with than those without leukocytes in semen.Conclusions
Higher levels of reactive oxygen species are found in washed seminal cells and purified sperm after vasectomy reversal than in those of fertile men. Although leukocytes are probably a significant source of reactive oxygen species in these groups, they may not account for all of the increased reactive oxygen species after vasovasostomy. Low motility after vasectomy reversal may be related to the detrimental effects of reactive oxygen species produced by leukocytes or sperm, even in men without clinical leukocytospermia. 相似文献122.
PIERO G. TOGNINI RICHARD S. FOSTER PETER McGRAW DOUGLAS HEILMAN RICHARD BIHRLE RANDALL G. ROWLAND GREGORY R. WAHLE LARRY H. EINHORN JOHN P. DONOHUE 《The Journal of urology》1998,159(6):1833-1835
Purpose
We determine if post-chemotherapy resection of residual retroperitoneal and chest tumor under the same anesthetic is reasonable based on tumor pathology and morbidity, and if the finding of necrosis in the abdomen allows observation of chest tumor.Materials and Methods
We retrospectively reviewed 143 post-chemotherapy patients who underwent resection of residual retroperitoneal and chest disease under the same anesthetic.Results
Retroperitoneal pathology was generally predictive of chest pathology. Concordance existed in 77.5% of patients with necrosis, 70% with teratoma and 69% with cancer of the abdomen. However, the correlation was much stronger (86%) in predicting necrosis/fibrosis if cases were categorized as uncomplicated by Indiana University criteria. Although the morbidity of the combined approach is higher than that of standard post-chemotherapy retroperitoneal lymph node dissection, it was acceptable.Conclusions
The morbidity of post-chemotherapy retroperitoneal lymph node dissection and resection of chest disease under the same anesthetic is acceptable. Retroperitoneal pathology generally predicts chest pathology but this correlation is much stronger if the case is uncomplicated based on our criteria. In an uncomplicated case the discovery of necrosis of the abdomen allows observation of chest tumor. 相似文献123.
CAROL A. GREGORY MARTIN ORRELL BARBARA SAHAKIAN JOHN R. HODGES 《International journal of geriatric psychiatry》1997,12(3):375-383
Objective. To compare the performance of patients with frontotemporal dementia (FTD) and Alzheimer's disease (AD) on a range of simple neuropsychological tests. Design. A battery of neuropsychological tests easily applied at the bedside, consisting of traditional tests of memory, attention and executive function, were given together with tests of motor sequencing and examination of frontal release signs. In addition, we devised a theoretically motivated test of dual attention—a story with distraction which also contained a ‘social dilemma’. Setting. Specialist memory and cognitive disorders clinic. Patients. 12 patients with FTD and 12 patients with AD, matched for overall level of dementia on the Mini-Mental State Examination, were selected. Results. In general, the difference in results between FTD and AD patients was small. However, a composite score derived from the presence of a grasp and pout reflex, the number of perseverations during category fluency for animals and response to the social dilemma within the two stories produced a sensitivity of 83.3% and specificity of 91.6%. There was also a highly significant difference between patients with FTD and AD in scores achieved on the Clinical Dementia Rating Scale reflecting the marked change in behaviour that patients with FTD suffer, even at a stage when memory functions are well preserved. Conclusion. Traditional neuropsychological tests were poor at differentiating cases of FTD and AD; however, a composite (SIFTD) score appears potentially useful but requires prospective validation. Better methods of assessing the changes in comportment that characterize the early stages of FTD are required. © 1997 by John Wiley & Sons, Ltd. 相似文献
124.
NINA C. GONNELLA XIAOLU ZHANG YONG JIN OM PRAKASH C. GREGORY PARIS ISTVAN KOLOSSVRY WAYNE C. GUIDA REGINE S. BOHACEK ISIDOROS VLATTAS TERRI SYTWU 《Chemical biology & drug design》1994,43(5):454-462
The conformations of cyclo(-D-Trp-D-Asp-Pro-D-val-Leu-) in dimethyl sulfoxide-d6 (DMSO-d6) and water were determined using two-dimensional nuclear magnetic resonance spectroscopy and restrained molecular dynamics. Comparisons were made between conformations of the cyclic pentapeptide in both solvents. The NMR study revealed that, while the backbone remained relatively unchanged in both solvents, the side-chains adopted distinctly different orientations in DMSO-d6 vs. H2O. A modeling study, minus NOE constraints, produced a set of low-energy conformers possessing agreement in backbone conformation with the NMR-derived structures; however, lowest-energy conformers did not have this agreement. These results show that different solvents can significantly affect the preferred side-chain conformation of small cyclic peptides in solution. This finding will impact the selection of solvent when determining structures for use as templates in rational drug design. 相似文献
125.
GREGORY W. BARSNESS M.D. E. MAGNUS OHMAN M.D. ROBERT M. CALIFF M.D. DEAN J. KEREIAKES M.D. BARRY S. GEORGE M.D. ERIC J. TOPOL M.D. 《Journal of interventional cardiology》1996,9(2):89-115
Beginning with its inception in 1985, the TAMI group performed randomized clinical trials in both academic: and nonacademic settings. The ten TAMI trials not only proved the viability of clinical research in a nontraditional environment, but also contributed significantly to the clinical investigation of acute myocardial infarction through small mechanistic trials. Despite having insufficient power to address overall survival and clinical outcome measures because of patient enrollments ranging from only 50–575 patients, the trials used similar entry criteria and follow-up measures, which permitted broader analyses of the prospectively collected dataset of randomized patients. This article reviews the history of the TAMI collaboration and discusses the findings of the individual trials as well as the contributions of larger analyses to our understanding of patient selection, prognosis, costs, and outcomes. (J Interven Cardiol 1996;9:89–115) 相似文献
126.
127.
128.
EFFECT OF MORPHINE ON CORTISOL AND PROLACTIN SECRETION IN ANOREXIA NERVOSA AND DEPRESSION 总被引:1,自引:0,他引:1
ATHANASIOS P. ZIS RONALD A. REMICK CAMPBELL M. CLARK ELLIOT GOLDNER B. E. KELLY GRANT GREGORY M. BROWN 《Clinical endocrinology》1989,30(4):421-427
Endogenous opioid peptides are involved in feeding regulation, and alterations in opioidergic regulation have been implicated in the pathophysiology of eating disorders. To investigate further this hypothesis, we conducted a placebo-controlled study of the effect of the opiate alkaloid morphine on cortisol and prolactin secretion in six patients with anorexia nervosa and six age-matched healthy volunteers, and compared the results with those obtained in nine depressed patients. Basal cortisol but not basal prolactin levels were elevated in patients with anorexia nervosa and patients with depression. Following the administration of morphine plasma concentrations of cortisol levels declined progressively and at a similar rate in all three groups. The prolactin response to morphine was attenuated significantly in patients with depression. Neither the cortisol and prolactin response to morphine in the anorectic patients nor the cortisol response in the depressed patients we observed in this study suggests altered opiate receptor sensitivity. However, the decreased prolactin response to morphine in depressed patients remains compatible with this hypothesis. 相似文献
129.
JAMES P. DAUBERT ROBERT H. HOYT† ROY JOHN‡ LARRY CHINITZ§ DAVID T. MARTIN‡ CHRISTOPHER FELLOWS GREGORY FELD¶ WILLIAM PELKEY# RUCHIR SEHRA for theCryoCor Atrial Flutter Investigators 《Pacing and clinical electrophysiology : PACE》2005,28(S1):S142-S145
We sought to evaluate prospectively the safety and efficacy of cryothermal energy to ablate typical atrial flutter (AFL). Ablation of cardiac tissue using cryothermal energy has recently been developed as an alternative to radiofrequency energy, which may offer certain advantages in the treatment of AFL. This prospective, multicenter nonrandomized study of a new catheter-based system for the treatment of cavotricuspid isthmus (CTI)-dependent AFL enrolled patients between 18 and 75 years of age. The CTI dependence of AFL was confirmed at electrophysiologic study with activation mapping and/or entrainment. Patients with atrial septal defect, recent myocardial infarction, left ventricular ejection fraction <0.30, or prior AFL ablation were excluded. Cryoablation of AFL was performed in 48 patients from 11 centers. The procedure was immediately successful in 45 patients (94%), and effective in 30 of 40 patients with complete data available at 6 months. Cryoablation is a promising new treatment of CTI-dependent AFL refractory to medical therapy. Further improvements in catheter design and intravascular sheaths will be tested in a larger multicenter trial. 相似文献
130.