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51.
目的观察国产鼻喷鲑鱼降钙素治疗骨质疏松性疼痛的疗效。方法采用随机分组对照设计。选择骨质疏松患者53例,随机分为两组,治疗组(30例)给予鼻喷鲑鱼降钙素,20u/次,1次/天,8周为1个疗程,停药后继续观察3周。对照组(23例)口服钙尔奇D片,1片/次,1次/天,共8周;采用国际惯用分级标准对疼痛予以评估。结果治疗组患者的疼痛明显改善,其总有效率为95%;在停药后缓解疼痛的作用仍可维持4周以上,Ⅲ度骨质疏松患者的治疗效果较Ⅰ度和Ⅱ度患者的效果差;对照组症状未见明显改善。结论用国产鼻喷鲑鱼降钙素治疗骨质疏松性骨痛,可明显缓解患者的疼痛症状。 相似文献
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53.
The potassium conductance increased by BRL 34915 (BRL, cromakalim) was studied in single guinea pig ventricular myocytes by using a whole cell voltage-clamp technique. In control voltage-clamp recordings, the late current-voltage relation showed a distinct inward rectification. BRL (1–100 μM) shortened the action potential and diminished or abolished inward rectification but had no effect on the slope conductance and currents flowing during hyperpolarizing clamp steps. BRL did not decrease the slow inward current but accelerated the time constant of activation and amplitude of the outward current. Cd markedly decreased (0.2 mM) or abolished (0.4–0.6 mM) the slow inward current and BRL induced a faster outward shift of late current to a greater value. Glybenclamide (10 μM), a blocker of ATP-sensitive K+ channels, had little effect of its own on action potential, membrane currents, and I-V relation. However, in the presence of BRL, glybenclamide abolished BRL effects on action potential and currents and restored inward rectification. It is concluded that the mechanism by which BRL shortens the action potential is a faster growth of an outward current due to the reduction or abolition of the inward rectification of an ATP-dependent potassium channel. The reduction in force in non-isolated tissues appears to be an indirect result of the action potential shortening and not of a decreased slow inward current. 相似文献
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55.
无框架MRI导航下的内镜经蝶鞍区肿瘤切除术 总被引:1,自引:0,他引:1
目的探讨无框架MRI导航系统在内镜经蝶垂体腺瘤和颅咽管瘤切除术中的作用.方法对8例垂体腺瘤和2例颅咽管瘤病人在无框架MRI影像导航引导内镜下经蝶入路切除肿瘤.结果机器定位误差平均1.5mm,重要结构和病变定位满意,导航注册时间平均5 min,手术时间平均50min,术后病人症状均减轻.结论在内镜经蝶鞍区手术治疗中,无框架影像导航使重要结构及病变定位准确,可在手术中发挥重要作用. 相似文献
56.
[目的]比较2,4-二氯苯胺重氮法(DCA)和钒酸盐氧化法检测血清结合胆红素的结果。[方法]根据NCCLS(EP6-P)评价方案,评估两种方法的相关性和偏倚。[结果]两种方法的检测结果相关性良好(r=0.9985),Ⅰ、Ⅱ、Ⅲ组检测结果无差异,Ⅳ组结果有差异。[结论]应建立与方法学相对应的血清结合胆红素参考值范围。 相似文献
57.
We have examined polyol pathway kinetics in the lenses of rats made diabetic with streptozotocin. At up to 11 days after diabetes induction, the lenses were isolated and subjected to 'pulse-chase' studies: the lenses were incubated with [13C]glucose and lens metabolism followed by [13C]nuclear magnetic resonance (NMR) spectroscopy. Proton NMR spectroscopy was also performed to measure the hexose monophosphate shunt (HMPS) activity. The results showed that (1) the activity of aldose reductase increased initially and decreased after 11 days of diabetes; (2) the fructose pool increased initially but started to decline after 3 days; (3) the HMPS activity increased nearly 40% immediately after diabetes induction; and (4) the turnover rates of glucose, alpha-glycerophosphate (GP), lactate, sorbitol, and fructose were 80.8 +/- 2.6, 10.1 +/- 1.4, 47.7 +/- 3.7, 7.9 +/- 0.9 and 5.2 +/- 2.2 nmol hr-1 lens-1 (34 mg wet weight lens-1), respectively. Up to 35% of lactate appeared to derive from the polyol pathway. Further, GP was rapidly metabolized, although its fate is currently unknown. These results reveal a far more complex pattern of glucose metabolism in the diabetic lens than that in lenses incubated in high glucose. 相似文献
58.
Han B Jaurequi J Tang BW Nimni ME 《Journal of biomedical materials research. Part A》2003,65(1):118-124
While attempting to find a suitable crosslinking reagent for biopolymers, a naturally occurring proanthocyanidin (PA) obtained from grape seeds was selected to fix biological tissues. The cytotoxicity and crosslinking rate, reflected by the in vitro and in vivo degradation of fixed matrices has been studied. The shrinkage temperature of the fixed bovine pericardium increased from 66 to 86 degrees C. A cytotoxicity assay using fibroblast cultures revealed that PA is approximately 120 times less toxic than glutaraldehyde (GA), a currently used tissue stabilizer. In vitro degradation studies showed that fixed tissue was resistant to digestion by bacterial collagenase. Crosslinks between PA and tissues can be stabilized by decreasing the dielectric constant of the solution during storage. After subcutaneous implantation for periods ranging between 3 and 6 weeks, we found no apparent degradation of the GA- or PA-fixed tissues, whereas fresh tissue controls rapidly disintegrated. Beyond 6 weeks PA crosslinks began to degrade. More fibroblasts migrated and proliferated inside the PA-fixed implants compared with GA counterparts. Tissues crosslinked with PA manifested an enhanced collagen expression and deposition and did not calcify after implantation. GA, on the other hand, even after thorough rinsing continued to be cytotoxic, inhibited collagen synthesis and encouraged dystrophic calcification. Collagen matrices crosslinked with PA are expected to be of value in the design of matrices that will encourage cell ingrowth and proliferation, which are temporary in nature, and that are intended to regenerate or replace missing tissues, which can delay the biogradation of collagen. As such they should be of significant value in the emerging field of tissue engineering. 相似文献
59.
Conclusions NT antibodies to LI virus were found in the sera of Swedish cows from many parts of the country although only exceptionally in the north. The prevalence of positive specimens increased markedly towards the southeast. This geographic distribution apparently fits well with the occurrence of ticks in the country. An analysis, now in progress, of RSSE-LI antibodies in human cases of meningoencephalomyelitis seems to indicate a closely similar distribution of the human RSSE infections. It is thus obvious that the screening of cow sera for LI antibodies provides reliable information as to endemic regions of RSSE-LI-like viruses. There was nothing to suggest that nonspecific reactions occurred or impaired the results; in fact the very uneven geographic distribution of positive specimens, of high as well as low titers, should argue for specificity of the reaction.Aided by a grant from the Swedish National Association against Poliomyelitis.The skilful technical assistance of MissSiri Austrin, MissIngrid Lövhvist, MissBrita Gustafson and Mr.Nils Lundh is gratefully acknowledged. 相似文献
60.
目的研究1例17α-羟化酶/17,20-裂解酶部分性联合缺陷症患者CYP17A1基因突变特点,并结合患者的临床表现与基因突变类型初步探讨P450C17酶蛋白的结构与功能的关系。方法收集1例17α-羟化酶/17,20-裂解酶部分性联合缺陷症患者的临床资料及其亲属血标本,提取基因组DNA,设计7对引物扩增CYP17A1基因的8个外显子及外显子与内含子的连接区域,琼脂糖凝胶电泳鉴定PCR产物,产物胶回收后直接做为DNA双链模板测序。DNA双链模板不一致的PCR产物经克隆后测序。测序结果在核苷酸序列数据库进行比较分析。结果患者CYP17A1基因突变检测结果为5994-5995delAT/7541C>T复合杂合子。这两种突变均未见报道。推测5994-5995delAT导致I259H,274X,突变形成的截短蛋白质缺少血红素结合区域,因此是没有功能的;而通过人类P450C17酶计算机模型分析显示7541C>T导致的A398V远离酶的活性中心,推测突变可能使酶的活性减弱,而不是完全地丧失。患者临床表现为有自发不规则月经及轻度高血压、低血钾,结合激素测定结果提示肾上腺和性腺保留部分功能。因而患者的基因型与其临床表型是一致的。结论应进行突变P450C17酶的功能学研究来进一步明确结构改变对功能的影响。 相似文献