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排序方式: 共有1209条查询结果,搜索用时 156 毫秒
151.
L Poulakos J H Elwell J W Osborne L F Urdaneta M Hauer-Jensen A P Vigliotti D H Hussey R W Summers 《Journal of surgical oncology》1988,38(2):130-135
During intraoperative radiation therapy for carcinoma of the head of the pancreas in humans, a portion of duodenum is often at risk for radiation-induced complications because of its fixed anatomical position within the treatment field. This study was undertaken to determine the feasibility of using the rat as a model to determine the radiotolerance of normal mammalian duodenum. The procedures used to exteriorize and irradiate a selected segment of duodenum are described. Histopathologic changes in 5-cm segments of midduodenum were studied 14 and 28 days after 0, 30, 40, or 50 Gy X-radiation. Complete denudation of the epithelium and thickening of the muscularis and serosal layers occurred in all irradiated segments by day 14. By day 28, even though crypt and villus architectures were atypical, large areas of epithelial regeneration were seen in rats receiving 30 Gy. In contrast, complete denudation of the epithelium were still evident along most of the length of the irradiated segments in rats receiving 40 or 50 Gy. Serosal fibrosis was prominent in all irradiated animals, regardless of dose. These results indicate that radiation doses above 30 Gy carry high risks of complications. The rat is considered a suitable animal model. 相似文献
152.
Effect of parental age on fertilization and pregnancy characteristics in couples treated by intracytoplasmic sperm injection 总被引:11,自引:5,他引:6
Spandorfer SD; Avrech OM; Colombero LT; Palermo GD; Rosenwaks Z 《Human reproduction (Oxford, England)》1998,13(2):334-338
The purpose of this study was to investigate any influence of maternal
and/or paternal age on gamete characteristics and pregnancy outcomes in
intracytoplasmic sperm injection (ICSI) cycles. In all, 821 consecutive
ICSI cases were analysed retrospectively. While a significant linear
decline in semen volume was detected, no significant differences in the
concentration, motility or morphology of the spermatozoa were found with
paternal ageing. A significant decline in the number of oocytes retrieved
and the number of mature oocytes obtained was found with advancing maternal
age. An increase in the occurrence of digyny was noted with parental
ageing, while no difference in single or bipronuclear fertilization was
found. Older women had a decreased incidence of single pronucleus formation
and an increase in digyny, but no significant difference in the percentage
of oocytes that underwent two-pronuclear fertilization was detected with
regard to maternal ageing. Pregnancy outcomes were not influenced by the
age of the male partner, while a strong negative correlation was found with
maternal ageing. To better analyse male partner ageing as a factor
affecting pregnancy outcome, we analysed a subgroup of patients with a
female partner aged <35 years who underwent ICSI. No paternal influence
on ICSI pregnancy outcome was found in this subgroup of patients. We
conclude that the influence on pregnancy outcome after ICSI is related
mostly to maternal and not paternal age.
相似文献
153.
Immune complex glomerulonephritis and chronic anaerobic urinary infection--complications of filariasis 总被引:2,自引:0,他引:2
A D Ormerod J Petersen J K Hussey J Weir N Edward 《Postgraduate medical journal》1983,59(697):730-733
We describe a patient with chyluria due to abdominal Bancroftian filariasis. The patient showed two unusual complications, an immune complex glomerulonephritis and a chronic urinary infection. We also discuss the use of the CT whole body scanner in the diagnosis and delineation of the extent of the disease. 相似文献
154.
155.
Retrospective analysis of outcome in 137 patients who underwent radical perineal prostatectomy and bilateral injection of gold-198 implants into the periprostatic tissues and/or neurovascular pedicles as treatment for prostatic adenocarcinoma was performed. Patients had undergone treatment between 1975 and 1985. Local recurrence developed in 22 patients (16.1%) and distant metastases developed in 33 (24.1%). Clinical and surgical staging of disease and Gleason grading of pathologic specimens were performed retrospectively. Kaplan-Meier local recurrence, freedom from relapse (FFR), and survival rates decreased with increasing stage and pathologic grade. With clinical staging, these rates were not statistically different from previous rates achieved with external beam radiation therapy, and with pathologic staging, they were not statistically different from previous rates achieved with prostatectomy. The authors conclude that (a) 5-year follow-up is inadequate to determine local control rates after prostatectomy; (b) use of implants did not improve local control, FFR, or survival rates of 10 years; and (c) method of staging probably has more effect on local control, FFR, and survival rates than does treatment modality. 相似文献
156.
D J Hermann T F Krol G E Dukes E K Hussey M Danis Y H Han J R Powell L J Hak 《Journal of clinical pharmacology》1992,32(2):176-183
Twelve healthy male subjects completed this randomized, placebo controlled, four-period crossover trial to determine the effect of verapamil, diltiazem, and labetalol on the bioavailability and metabolism of imipramine. Subjects received a 7-day course of one of four treatments; verapamil (120 mg every 8 hr), diltiazem (90 mg every 8 hr), labetalol (200 mg every 12 hr), or placebo (every 12 hr) during each study period. Imipramine (100 mg) was administered orally on the morning of day 4 of each study period. Plasma and urine samples were collected periodically over the ensuing 96 hours. Samples were assayed by HPLC for imipramine, desipramine, 2-hydroxyimipramine, and 2-hydroxydesipramine. Verapamil, diltiazem, and labetalol increased imipramine area under the plasma concentration time curve (relative bioavailability) as compared with placebo by 15%, 30%, and 53%, respectively. Verapamil and diltiazem did not demonstrate consistent changes in the formation of the measured metabolites. Labetalol caused a significant decrease in the amount of imipramine metabolized to 2-hydroxyimipramine (mean decrease: 22%) and from desipramine to 2-hydroxydesipramine (mean decrease: 8%). The molar ratios of plasma AUC of 2-hydroxyimipramine and 2-hydroxydesipramine to the parent compounds were significantly decreased. Since these metabolic processes are dependent on the cytochrome P450IID6 isozyme, these data suggest that labetalol decreases the oral clearance of imipramine by inhibiting this system. All three of these commonly used agents decreased the oral clearance of imipramine. These drug interactions could lead to elevated imipramine concentrations and have the potential for clinically important adverse events. 相似文献
157.
1-溴-2-甲氧基萘与0-对在苯磺酰乳酸乙酯(1)在无水氯化铝催化下化Friedel-Crafts反应,还原脱溴直接合成dl-1a萘普生(3),以上反应均在“一锅”内完成,收率达95。 相似文献
158.
159.
160.
Gary D. Frentz M.D. Jorgen U. Schlegel M.D. John L. Hussey M.D. Richard Prima M.D. 《Urology》1981,18(6):546-555
Renal transplant recipients and donors were studied serially with quantitative renal scintillation camera studies utilizing 131I-Hippuran and 99mTc-Iron ascorbate. This study allows for determination of effective renal plasma flow (ERPF), glomerular filtration rate (GFR), filtration fraction (FF), and predicted return in ten minutes. A drop in FF occurred with, or preceded clinical rejection; whereas, an increase in FF occurred with acute tubular necrosis (ATN) caused by preservation injury, aminoglycosides, and following acute rejection. Combined with the other parameters of renal function determined by this technique, FF alternation proved useful in the differentiation of ATN from rejection and in predicting the prognosis of renal homografts. 相似文献