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991.
992.
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
993.
This article examines the distribution of positive blood alcohol levels (BALs) among emergency room patients and the relationship between intoxication and other variables. Approximately one-quarter of the 640 subjects had positive blood alcohol levels and 16.3% had BAL readings above 0.10%, the legal limit for operating a motor vehicle in most states. Chi-square tests and logistic regression analysis indicated a significant relationship between employment status, gender, educational attainment, age and BAL. There were no significant racial differences. Analysis of the role of the presenting problem with BAL revealed that being involved in an accident was significantly predictive of a high BAL in a multivariate context. However, patients presenting with psychiatric problems had overall higher levels of intoxication than other patients. These findings have major implications for public policy formulation vis-à-vis public health delivery. 相似文献
994.
Geoffrey G. Hallock M.D. 《Aesthetic plastic surgery》1989,13(4):285-289
Reconstitution of the nasal scaffolding with maintainence of soft tissue proportions either following severe facial trauma or as a sequela to aesthetic rhinoplasty misadventures frequently is best achieved using the stability afforded by bone grafts. Split cranial bone grafts offer many advantages and may be the donor site of choice, and may even allow such surgery to be performed on an outpatient basis in some cases. The use of miniplate or screw osteosynthesis, now commonly accepted as a superior technique in craniomaxillofacial procedures, may simplify fixation of these calvarial nasal bone grafts with an apparent decrease in the risk of resorption. 相似文献
995.
The sequence of structural changes involved in postnatal photoreceptor differentiation, maturation and early degeneration was studied in young Abyssinian cats and kittens with hereditary rod-cone degeneration and compared to maturation in normal controls. In affected cats the earliest change seen was disorientation of outer segment discs in the majority of the rods, while other rods appeared to develop and mature normally. Such disorientation of discs (at oblique angles or parallel to the longitudinal axis of the outer segment, or whorls of discs) is considered as 'immaturity', since controls also showed a substantial number of disoriented rod outer segment discs at this young age. At postnatal day 35 the difference between affected animals and controls was marked with a high frequency of immature appearing rod outer segment discs in affected animals, while all rod outer segment discs were adult-like and arranged in an orderly manner in controls. Cones seemed unaffected at this age. More severe changes in affected rod outer segments in the form of disintegration of discs (vacuolization and clumping of disc material, or formation of debris), which we consider to represent degeneration, were first observed at the time when retinal maturation normally occurs in the cat, i.e. 150 days postnatally. Subsequently a drop-out of rods was seen, primarily of rods with disoriented and disintegrated outer segment discs, followed by a slow, progressive degeneration of rods that had developed and matured normally. Cones appeared normal during the time of retinal development and maturation and it was not until the age of 2-3 years (Narfstr?m and Nilsson, 1986, Incest. Ophthalmol, Vis. Sci. 27, 1569-76) that degenerative changes were seen also in cones. 相似文献
996.
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
997.
998.
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
999.
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
1000.