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排序方式: 共有1734条查询结果,搜索用时 31 毫秒
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Alpha-adrenoreceptor reagents. 4. Resolution of some potent selective prejunctional alpha 2-adrenoreceptor antagonists 总被引:1,自引:0,他引:1
A P Welbourn C B Chapleo A C Lane P L Myers A G Roach C F Smith M R Stillings I F Tulloch 《Journal of medicinal chemistry》1986,29(10):2000-2003
The resolution of three 2-substituted derivatives of idazoxan is described. The enantiomers show large separations in activity in a variety of in vitro and in vivo tests, and the active isomers are all potent and selective antagonists at the alpha 2-adrenoreceptor. The significance of these results in relation to those published on the enantiomers of idazoxan and to those on optically active alpha 2-adrenoreceptor agonists is discussed. 相似文献
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Strahlentherapie und Onkologie - Several randomized trials have demonstrated that men with localized prostate cancer benefit from the use of short-term neoadjuvant androgen deprivation therapy... 相似文献
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Modulation of the hypolipidemic effect of fish oils by dietary fiber in rats: studies with rice and wheat bran 总被引:1,自引:0,他引:1
D L Topping R J Illman P D Roach R P Trimble A Kambouris P J Nestel 《The Journal of nutrition》1990,120(4):325-330
Adult male rats were fed a purified diet containing rice bran or wheat bran with or without a marine fish oil to investigate the possible effects of such dietary combinations on lipid metabolism. Plasma and hepatic triacylglycerols and hepatic lipogenesis were lowered significantly by feeding fish oil with rice bran but not with wheat bran. Plasma cholesterol and hepatic cholesterol synthesis were significantly lower in animals fed fish oil with either bran. Liver microsomal free cholesterol was significantly lower in rats fed rice bran alone than in all other groups. Hepatic low density lipoprotein (LDL) receptor activity was significantly higher in the two groups fed rice bran than in the two groups fed wheat bran. Fish oil significantly decreased hepatic LDL receptor activity and increased hepatic high density lipoprotein (HDL) binding activity with wheat bran but had no significant effects on these parameters when added to the rice bran diet. However, when the data for all groups were pooled, there was a significant negative correlation between hepatic HDL binding activity and LDL receptor activity. Cecal volatile fatty acids were significantly higher in rats fed rice bran, were unaffected by adding fish oil to either bran diet and did not appear to mediate any of the effects of the brans and fish oil on plasma lipids and hepatic lipid metabolism. The combination of rice bran plus fish oil therefore appears to have more beneficial effects on lipid metabolism than wheat bran plus fish oil. 相似文献
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T C Ryken P W Hitchon R M Roach V C Traynelis 《Stereotactic and functional neurosurgery》1992,59(1-4):111-114
A review of the stereotactic cases performed at the University of Iowa between February, 1985, and December, 1990, yielded 12 infratentorial stereotactic biopsies in 11 patients. A definitive diagnosis was obtained in 9 of 11 patients. One patient required a second biopsy to obtain a diagnosis and 1 yielded cystic fluid only. The pathological diagnosis obtained included 4 high-grade gliomas, 2 undifferentiated adenocarcinomas, 2 low-grade astrocytomas, 1 malignant ependymoma, 1 pontine hematoma and 1 cyst. None of the patients experienced increased neurological deficit following biopsy and there was no mortality. One patient developed postoperative meningitis. We conclude that stereotactic biopsy of infratentorial lesions can be performed safely with a high probability of obtaining a diagnosis. Adequate tissue diagnosis is necessary to direct further therapy. 相似文献
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Transient Osteoporosis of the Hip in Pregnancy 总被引:1,自引:0,他引:1
Sashi Siva Vijay Roach 《The Australian & New Zealand journal of obstetrics & gynaecology》1997,37(3):261-266
Summary: Transient osteoporosis of the hip (TOH) is an uncommon condition. This painful regional osteoporosis affects previously healthy women in the third trimester of pregnancy. It is characterized by pain in the affected hip and pronounced osteopenia of the femoral head and neck. It has a relatively short clinical course (average 6 months) and a predictably benign prognosis. Complete clinical and radiological recovery is the rule. The diagnosis is one of exclusion. The cause of the osteopenia is not known, although various aetiological factors have been implicated. A case of TOH occurring in the third trimester of pregnancy with complete recovery within 6 months postpartum is presented. 相似文献
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J D Helman J M Leung W H Bellows N Pineda G W Roach J D Reeves J Howse M T McEnany D T Mangano 《Anesthesiology》1992,77(1):47-62
Desflurane, a coronary vasodilator, may induce myocardial ischemia in patients with coronary artery disease. To determine whether desflurane is safe to administer to the at-risk patient population (with known coronary artery disease), we compared the incidence and characteristics of perioperative myocardial ischemia in 200 patients undergoing coronary artery bypass graft (CABG) surgery randomly assigned to receive desflurane (thiopental adjuvant) versus sufentanil anesthesia. Under conditions of hemodynamic control, perioperative ischemia was assessed using continuous echocardiography (precordial: during induction; transesophageal: during surgery) and Holter electrocardiography (ECG); hemodynamics (including pulmonary artery pressure) were measured continuously. Hemodynamic results: During induction, no significant changes in hemodynamics occurred in the sufentanil group, while in the desflurane group, heart rate, systemic and pulmonary arterial pressure increased and stroke volume decreased significantly. During the intraoperative period, the incidence of hemodynamic variations was low in both anesthetic groups; however, the prebypass incidence of tachycardia (greater than 120% of preoperative baseline heart rate) was greater in the desflurane group (4 +/- 7% of total time monitored) than in the sufentanil group (1 +/- 6%) (P = 0.0003). Similarly, the incidence of prebypass hypotension (less than 80% of preoperative baseline systolic arterial blood pressure) was greater in the desflurane group (21 +/- 14%) than in the sufentanil group (15 +/- 16%) (P = 0.01). ECG results: Preoperatively, 15% (28/191) of patients developed ECG ischemia, with no difference between patients who received desflurane, 13% (12/96) or sufentanil, 16% (16/95) (P = 0.6). During anesthetic induction, 9% (9/99) of patients who received desflurane developed ECG ischemia, compared with 0% (0/98) who received sufentanil (P = 0.007). During the prebypass period, 5% (10/197) of patients developed ECG ischemia, with no difference between patients who received desflurane, 7% (7/99) or sufentanil, 3% (3/98) (P = 0.3). Postbypass, 12% (24/194) of patients developed ECG ischemic changes, with no difference between patients who received desflurane, 13% (13/97) or sufentanil, 11% (11/96) (P = 0.9). Echocardiographic results: The incidence of precordial echocardiographic ischemia during anesthetic induction was 13% (5/39) in the desflurane group versus 0% (0/29) in the sufentanil group (P = 0.1). Moderate to severe transesophageal echocardiographic (TEE) ischemic episodes occurred in 12% (21/175) of patients during prebypass, with no significant difference between the desflurane group, 16% (15/91) and the sufentanil group, 7% (6/84) (P = 0.09). TEE ischemic episodes occurred in 27% (49/178) of patients during the postbypass period, with no difference between the desflurane, 29% (27/92) and sufentanil, 25% (22/86) groups (P = 0.7).(ABSTRACT TRUNCATED AT 400 WORDS) 相似文献
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J R Shearer H I Roach S W Parsons 《The Journal of bone and joint surgery. British volume》1992,74(1):39-44
We describe the histology of a specimen taken from an amputated leg seven months after a 15 cm bone gap in the tibia had been closed by bone transport. Lengthening appeared to have occurred by repeated minor trauma to the bone, with the fractured trabeculae in sufficiently close contact for the repair process to proceed. Osteogenesis did not occur through a cartilage phase, but the fracture gaps were bridged by collagen fibres, around which new bone formed. Microfractures had repaired by primary healing with woven bone and with no microcallus. Small regions of bone were necrotic. Resorption of the necrotic bone and remodelling of the immature bundle and woven bone were still at an early stage, suggesting that complete remodelling in man may take years rather than months. 相似文献