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991.
Immunogold localisation of laminin in normal and exfoliative iris.   总被引:1,自引:1,他引:0       下载免费PDF全文
Immunoelectron microscopic studies of exfoliative iris tissue (seven specimens) revealed the presence of laminin in the fibrillar component of exfoliation material. The immunogold label was uniformly distributed on the exfoliation fibres. Deposition of laminin labelled exfoliation material in the dilator muscle was a noteworthy feature, as was an apparent depletion of laminin in the basement membranes of ostensibly unaffected vessels. In control iris tissue (five enucleated eyes) laminin was identified in the basement membrane round vascular contractile cells, but not beneath the endothelium.  相似文献   
992.
993.
Serotonin is a biogenic amine that can exert multiple effects on smooth muscle, including smooth muscle of the genitourinary tract; effects that may be species dependent. The present study using isolated tissues documents potent contractile responses to serotonin in canine bladder smooth muscle. Contractile responses to serotonin in canine bladder could be mimicked by alpha-methyl serotonin, a selective 5HT2 receptor agonist. In fact, although alpha-methyl serotonin was slightly less potent as a contractile agonist relative to serotonin, the contractile response to alpha-methyl serotonin was more persistent as evidenced by a greater recovery time to resting force following washout. In contrast, the 5HT1A receptor agonist, 8-OH-DPAT and the 5HT3 selective agonist, 2-methyl serotonin, did not markedly contract canine bladder. These data establish that contractile responses to serotonin in the canine bladder are mediated by activation of 5HT2 receptors. We further demonstrated that the 5HT2 receptor antagonist, LY53857, potently inhibited the contractile response to both serotonin and alpha-methyl serotonin in the canine bladder consistent with agonist activation of 5HT2 receptors. In contrast to the potent response to serotonin observed in the canine bladder, rat bladder preparations did not markedly contract in response to serotonin, alpha-methyl serotonin, 8-OH-DPAT, or 2-methyl serotonin. Thus, these studies reinforce the marked species variability in responsiveness to serotonin and indicate that contraction to serotonin in the canine bladder is mediated by activation of the 5HT2 receptor.  相似文献   
994.
995.
In the experiment on dogs and in patients with duodenal ulcer disease, it was established that the regulation of acid production besides the vagal nerves was mediated by the intragastric gastrin transport with the blood flow. A method of preoperative diagnosis of the intensity of intragastric blood flow permitting to define more accurately the indications for the choice of a method for surgical treatment has been developed. Supplementation of the selective proximal vagotomy with circular mucosectomy at the boundary between the antrum and body of a stomach enhances the effectiveness of operation due to reduction of the antral gastrin influence on the acid-producing zones of the stomach.  相似文献   
996.
In the article is presented classification, which takes into consideration mechanisms and sequence of spinal segment destruction in case of compression-flexion violence. On the basis of experimental and clinical data are shown the stages of destruction and their roentgenologic diagnosis, prognostication of some other damages, which are not detected by common methods. Differentiated curative tactics, taking account of necessary restorative measures in correspondence with stages and resolution types, is given.  相似文献   
997.
Argon laser pretreatment in Nd: YAG iridotomy   总被引:1,自引:0,他引:1  
Argon laser pretreatment prior to Nd:YAG laser iridotomy may decrease the incidence of operative hemorrhage. In a prospective, randomized clinical trial involving 12 patients (24 eyes), one eye was randomly assigned treatment with the Nd:YAG laser alone, while the other eye was pretreated with argon laser photocoagulation immediately prior to Nd:YAG laser. Eight of the 12 eyes (67%) treated with Nd:YAG laser alone had operative hemorrhages; only 2 of the 12 (17%) pretreated eyes did. Thus, argon laser pretreatment significantly reduced the incidence of hemorrhage during Nd:YAG iridotomy (P = .012).  相似文献   
998.
999.
1000.
Assay of FK 506 in plasma.   总被引:1,自引:0,他引:1  
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