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排序方式: 共有10000条查询结果,搜索用时 15 毫秒
991.
Ureteroscopic pyelolysis for pelviureteric junction obstruction 总被引:8,自引:0,他引:8
The development of endourological techniques for the treatment of upper urinary tract disease has concentrated mainly on the endoscopic treatment of upper urinary tract stones. The relief of pelviureteric junction obstruction (PUJ) by percutaneous pyelolysis has recently been reported and the use of the flexible uretero-pyeloscope has also been described. We describe the use of a rigid uretero-renoscopy to relieve strictures causing secondary pelviureteric junction obstruction in two cases. 相似文献
992.
We describe five new cases of autosomal recessive distal dystrophy (Miyoshi myopathy) and emphasize the distinctive clinical and laboratory features of this unusual muscular dystrophy. Symptoms began at age 15 to 25, the gastrocnemius muscles were selectively involved, and creatine kinase was elevated more than 10 times normal. The EMG showed abundant brief motor units with numerous fibrillations. Dystrophic features without vacuoles were best seen in the biceps femoris muscle. Asymptomatic creatine kinase elevation was present years prior to the development of weakness. The disorder appears to be inherited in an autosomal recessive pattern. Miyoshi myopathy can be distinguished from other distal muscular dystrophies. We propose a new classification for the distal muscular dystrophies. 相似文献
993.
Direct observation in vitro of how neuroblasts migrate: medulla and cochleovestibular ganglion of the chick embryo 总被引:4,自引:0,他引:4
The hypothesis that neuroblasts migrate in the nervous system by a locomotory process was tested experimentally. An in vitro preparation permitted direct observation of postmitotic cells migrating from the rhombic lip of the medulla and the anlage of the cochleovestibular ganglion. Cell locomotion was not seen. Instead migration was produced by elongation of a leading process, followed by translocation of the nucleus (perikaryal translocation). On the basis of comparisons with previous observations in situ, we propose that this represents a common mode of migration in the developing nervous system. Cell clusters were explanted from the rhombic lip at the developmental stage when they migrate from the ventricular zone to the acoustico-vestibular anlage in the medulla. Cells from the cochleovestibular ganglion were explanted after migration from the otocyst, but before ganglionic differentiation. Each neuroblast's migration route was formed by an elongating leading process ending in a growth cone. The growth cone attached to other cells and processes or ended freely on an acellular substrate. Nonneuronal cells usually migrated as has been described for fibroblasts, yet with some of the features of perikaryal translocation, but some nonneuronal precursor cells may migrate the way neuroblasts do. Neuroblasts did not migrate preferentially on the processes of nonneuronal cells, although the reverse could be observed. In fact a variety of interactions between migratory cells, neuronal and nonneuronal, were observed. The advantage of the experimental system described here is that one can observe cells migrating spontaneously at the times in development when they normally do so, while preserving the cellular populations present in situ. 相似文献
994.
J. Duteil FA Rambert AM Pointeau P. Mangiameli and E. Assous 《Fundamental & clinical pharmacology》1991,5(8):695-708
The potential antidepressant effect of flerobuterol (dl-(fluoro-2 phenyl)-1 t-butylamino-2 ethanol), a new drug related to beta-adrenoceptor agonists, was evaluated and compared with imipramine and salbutamol using classical psychopharmacological tests in mice. Like imipramine and salbutamol, flerobuterol (0.5-32 mg kg-1, ip) fully prevented apomorphine (16 mg kg-1, sc)- and partly reversed reserpine- and oxotremorine-induced hypothermia. At higher doses (16-32 mg kg-1), flerobuterol enhanced the toxic effects of yohimbine. Unlike imipramine, flerobuterol and salbutamol did not reduce immobility duration in the behavioural despair test. Salbutamol and flerobuterol decreased locomotor activity. Flerobuterol did not induce mydriasis, did not prevent oxotremorine-induced tremors or salivary and lacrimal gland secretion and did not reduce reserpine-induced palpebral ptosis. Propranolol (8 mg kg-1, ip) but not alpha-methyl-paratyrosine (75 mg kg-1, ip) prevented the flerobuterol-induced antagonism of apomorphine-induced hypothermia. Our results suggest that flerobuterol demonstrates potential antidepressant activity, which could be related to beta-adrenoceptor activation in mice. 相似文献
995.
When human divers and experimental animals are exposed to an increasing environmental pressure, they develop the high pressure neurological syndrome (HPNS) characterized by electroencephalographic changes and sleep and behavioral disturbances. In rats, behavioral disturbances essentially include hyperlocomotor activity (HLA), tremor and myoclonia. Moreover, HLA has recently been demonstrated to be linked to a pressure-induced striatal increase of dopamine (DA). In these experiments, it was proposed to investigate in rats, at the behavioral level, the role of DA receptors in the occurrence of the pressure-induced DA disturbances. DA receptor agonists were found to induce no significant changes in the development of HLA, tremor, and myoclonia. Alternatively, HLA was found to be dramatically antagonized by the use of DA receptor antagonists (SCH 23390, sulpiride, and haloperidol), while tremor and myoclonia only decreased in SCH 23390 experiments. 相似文献
996.
997.
A review of lacrimal drainage surgery 总被引:3,自引:0,他引:3
The advent of improved silicone intubation sets, increased understanding of lacrimal and nasal anatomy and physiology, and refinements in surgical instrumentation and technique have led to higher success rates in lacrimal surgery. Recent clinical studies, combined with new techniques in canalicular reconstruction, have helped identify which patients will benefit from surgical intervention and which techniques are indicated. Fortunately, this has greatly reduced the number of CDCRs necessary. 相似文献
998.
R Menningen M Günther N B?nninghoff C D Stahlknecht I Kubitza J Kusche 《Agents and actions》1986,18(1-2):38-40
In the operative treatment of appendicitis the so called negative appendectomy is an important issue because of its increased morbidity. From the hypothesis that the intestinal diamine oxidase activity is a suitable marker of mucosal integrity, the distribution pattern of the enzyme in appendices histologically classified as inflamed or not inflamed was studied. Histologically apparent inflammation of the appendix was connected with a significant reduction of diamine oxidase activity. The determination of this enzymic activity may be a simple and sensitive test for mucosal inflammation of the appendix even at a very early state. This could reduce the rate of negative appendectomies and influence thereby risk-cost-benefit calculations. 相似文献
999.
For monitoring the changes in intracellular free Ca2+ concentration ([Ca2+]i), we developed a simple system combining a fluorescence microscope, an image intensifier, a video-camera, a cathode ray tube display and a photodiode, employing quin2 as a Ca2+ indicator. We recorded increases of the fluorescence intensity due to [Ca2+]i rises, when high K+ medium, neurotransmitter and Ca2+ ionophore were applied to the single cells of nervous system origin in culture. The present system is capable of simultaneous detection of the [Ca2+]i changes from multiple separate cells. 相似文献
1000.
A López Bernal D J Hansell S Alexander A C Turnbull 《British journal of obstetrics and gynaecology》1987,94(11):1052-1058
The production of progesterone from pregnenolone, of cortisol from cortisone and of prostaglandin E (PGE) under basal and arachidonic acid-stimulated conditions was measured in cells dispersed from chorion and decidua. The cells were obtained after delivery from four groups of women: following spontaneous labour at term (38-42 weeks gestation), at elective caesarean section at term before the onset of labour, after induced labour at term, and after uncomplicated preterm (27-36 weeks) labour. Chorionic cells had a high progesterone output with relatively low cortisol and PGE production, whereas decidual cells had a high cortisol and PGE production rate. Free arachidonic acid stimulated PGE production in both decidual and chorionic cells. There were no significant differences in either steroid or PGE production among the four groups studied. These data suggest that steroid dehydrogenase activity in choriodecidual cells is not related to the mode of onset of labour and that the increased prostaglandin production in intrauterine tissues associated with parturition is due to enhanced availability of arachidonic acid. 相似文献