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951.
952.
S J Graafsma L J van Tits P van Heijst J Reyenga J F Rodrigues de Miranda T Thien 《Journal of cardiovascular pharmacology》1989,14(4):598-602
The effect of handgrip (HG) isometric exercise on plasma catecholamines, alpha 2-adrenoceptors on platelets and beta 2-adrenoceptors on lymphocytes was studied in normotensive subjects (NT) and essential hypertensive subjects (HT). Whereas systolic blood pressure (SBP) increases were similar in NT and HT subjects, diastolic blood pressure (DBP) and heart rate (HR) increased more in the former group. Baseline values and changes in plasma epinephrine (E) and norepinephrine (NE) did not differ between both groups. No differences were apparent in alpha 2-adrenoceptor density and affinity between NT and HT subjects before or after the test. HG isometric exercise induced a similar increase in beta 2-adrenoceptors on lymphocytes of 22 +/- 7 and 13 +/- 5% in NT and HT subjects, respectively. Affinity to the beta 2-adrenoceptors under baseline conditions was somewhat lower in HT (8.1 +/- 0.4 pM) than in NT subjects (6.5 +/- 0.5 pM), and this difference persisted during the test. Our results indicate that there are no differences in alpha 2- and beta 2-adrenoceptor densities either at baseline conditions or after HG isometric exercise between NT and HT subjects. Small differences noted in affinity to the beta 2-adrenoceptors require further investigation. 相似文献
953.
Outflow of aqueous humor following cyclodialysis or ciliochoroidal detachment in rabbit 总被引:1,自引:0,他引:1
Cyclodialysis and ciliochoroidal detachment were performed in three eyes of three rabbits and in three eyes of another three rabbits, respectively. After aspiration of the aqueous humor, 0.1 ml of 10% sodium fluorescein was injected intracamerally, and the eyeball was enucleated between 30 minutes and one hour after injection and prepared for fluorescence microscopy. Sodium fluorescein concentrations in the supraciliary space were much greater in the group with cyclodialysis or ciliochoroidal detachment than in the normal control group. These results suggest that (1) in the eye with cyclodialysis, the aqueous humor may freely gain access to the supraciliary space through the cleft between the anterior chamber and the supraciliary space and then be removed rapidly and (2) in the eye with ciliochoroidal detachment, the aqueous humor may pass through the uveoscleral outflow pathway. 相似文献
954.
955.
Two new naphtho-pyrone glycosides, 9-[(beta-D-glucopyranosyl-(1----6)-O-beta-D-glucopyranosyl)oxy]-10- hydroxy-7-methoxy-3-methyl-1H-naphtho[2,3-c]pyran-1 -one (5) and 6-[(alpha-apiofuranosyl-(1----6)-O-beta-D-glucopyranosyl)oxy]- rubrofusarin (6), together with cassiaside (3) and rubrofusarin-6-beta-gentiobioside (4) were isolated from the seeds of Cassia tora L. Their structures were elucidated on the basis of chemical and spectral data. The naphtho-gamma-pyrone glycosides (3, 4, and 6) were found to have significant hepato-protective effects against galactosamine damage, which were higher than that of silybin from Silybum marianum. 相似文献
956.
The role of body temperature in the morbidity and mortality resulting from acute severe carbon monoxide (CO) poisoning (2400 ppm CO, 90 min) was investigated using an unanesthetized animal model. Modified Levine prepared female rats (left common carotid artery and jugular cannulated) displayed a lower rate of recovery period (4 hr) re-warming, and an increased mortality rate and behaviorally-assessed neurologic index (NI) compared to normal rats. This indicated their greater susceptibility to CO hypoxia, although the degree of CO-induced hypothermia was the same in both groups. The whole-body cooling of Levine rats to a similar extent prior to CO exposure increased somewhat the post-CO re-warming rate, and marginally decreased NI and mortality during CO exposure (in-CO). In contrast, maintenance of constant body temperature by external heating during CO exposure resulted in a negative post-CO re-warming rate and sharply increased NI and in-CO mortality. Normal euthermic rats were much less severely affected by CO. The results suggest that hypothermia, whether CO-induced or produced by prior cooling, provides measurable protection of brain function during acute severe CO poisoning, and that maintenance of body temperature increases in-CO mortality and interferes with ability to thermoregulate and increases NI in survivors. 相似文献
957.
Edward T. Crosby Stephen H. Halpern Stephen H. Rolbin 《Journal canadien d'anesthésie》1989,36(6):701-704
The safety of epidural anaesthesia in patients with active, recurrent genital herpes simplex (HSV) infections is controversial. We reviewed the six-year experience of the use of epidural anaesthesia in this patient population in two institutions. Eighty-nine parturients with active genital HSV were administered epidural anaesthesia for Caesarean section. No patient suffered an adverse outcome related to either the anaesthetic or the virus. The theoretical risks of regional anaesthesia in the parturient with active herpes genitalis are reviewed. We conclude from available data that the risk of an adverse outcome is small and does not contraindicate the use of epidural anaesthesia in patients with recurrent infection. 相似文献
958.
Using a 31P-NMR spectroscopy, we monitored the metabolic kinetics of energy organophosphate compound in rat lens during the process of generating galactose cataract. The most remarkable metabolic change in the earlier phase of galactose cataract formation was found in alpha-glycerophosphate. This increased significantly, as compared to controls, since the day 3 of giving feed containing 25% galactose. The high level lasted for up to three weeks, decrease followed by a gradual decrease and subsequently a significant decrease at five weeks. Adenosine triphosphate (ATP) showed a significant decrease in the galactose group compared to the controls from two weeks after beginning of the experiment and the decrease continued. Inorganic orthophosphate increased gradually in the galactose group as compared to the controls, the increase being of significance at one week reading a maximum at two weeks followed by a subsegment decrease. Our basic study suggests that 31P-NMR spectroscopy is a useful technique in lens of the metabolic kinetics, to noninvasively determine the pathophysiology of galactose cataract, which has been studied biochemically and histologically. 相似文献
959.
960.