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341.
目的:分析普拉克索联合补肾活血通络胶囊治疗老年帕金森病的临床效果及对血清5-羟色胺(5-HT)、脑源性神经营养因子(BDNF)、S-100β水平的影响。方法:选择我院2014年12月~2016年12月收治的96例老年帕金森病患者,按随机数字表法分为对照组和研究组,每组48例。对照组采用普拉克索治疗,研究组基于对照组加以补肾活血通络胶囊治疗。观察并比较两组临床疗效指标统一帕金森病评分量表Ⅰ(unified parkinson’s disease rating scale,UPDRS)Ⅰ、UPDRSⅡ、UPDRSⅢ、UPDRSⅣ、总UPDRS,血清5-HT、BDNF、S-100β水平的变化及不良反应的发生情况。结果:治疗后,研究组总有效率为87.50%,显著高于对照组(64.58%,P<0.05)。两组治疗后的UPDRSⅠ、UPDRSⅡ、UPDRSⅢ、UPDRSⅣ、总UPDRS、血清S-100β水平均较治疗前显著下降,且研究组以上指标均明显低于对照组。两组治疗后的血清5-HT、BDNF水平均较治疗前明显上升,且研究组以上指标均明显高于对照组(P<0.05)。研究组不良反应发生率显著低于对照组(P<0.05)。结论:普拉克索联合补肾活血通络胶囊治疗治疗老年帕金森病的临床效果优于单用普拉克索,可能与其显著提高血清5-HT及BDNF表达并降低S-100β水平有关。  相似文献   
342.
Summary The present study deals with the localization and development of S-100 protein-like immunoreactivity in the retina, ciliary body and iris of human fetuses. In the retina, numerous astrocytes, densely distributed in the nerve-fiber layer and ganglion-cell layer, were stained strongly with the S-100 antiserum. The first immunoreactive astrocytes occurred at the posterior pole of the retina and spread gradually outward and toward the ora serrata with increasing age. Müller cells were not immunoreactive for S-100 during development, except in the retina of the latest fetus examined. S-100 immunoreactivity was also found in the nonpigmented ciliary epithelium and posterior epithelium of the iris, both of which are developed from the inner wall of the optic cup. On the other hand, the pigmented epithelium extending from retina to iris, derived from the outer layer of the optic cup, was free of S-100 immunoreactivity.  相似文献   
343.
目的:探讨乙酰肝素酶和S-100蛋白在人胃癌组织中的表达及其意义。方法:根据胃癌的病理大体分型将40例胃癌组织分为早期组和晚期组。其中,早期组同时未伴有淋巴结转移,晚期组伴有淋巴结转移。采用光镜、透射电镜、原位杂交和免疫组化方法对这两组胃癌组织的超微结构,乙酰肝素酶和S-100蛋白表达进行检测。结果:早期组乙酰肝素酶阳性表达细胞较少,晚期组阳性细胞较多,二者数密度和面密度比较。具有统计学意义(P<0.01);早期组S-100蛋白阳性表达细胞较晚期组多,二者比较,具有统计学意义(P<0.01);电镜观察可见:在胃癌早期,淋巴细胞和树突状细胞浸润较多,树突状细胞突起与淋巴细胞相接触,基底膜基本完整。晚期,基底膜几乎消失。淋巴细胞和树突状细胞浸润较少,癌细胞穿基膜明显。结论:乙酰肝素酶和S-100蛋白的表达程度可作为判定胃癌的侵袭和转移的指标,对其预后的判断具有参考价值。  相似文献   
344.
Foliar nutrient levels of broad-leaved tropical trees: A tabular review   总被引:1,自引:0,他引:1  
Foliar nutrient levels (N, P, S, K, Ca, Mg, Al, Fe, Mn, Zn, Cu, Mo, B), of about 40 tropical and subtropical broad-leaved trees, are listed and classified as deficient, low, intermediate, high, and toxic in each case according to the interpretation and evaluation of the reviewed author(s).  相似文献   
345.
Free energy derivatives, pictorial representation of free energy changes (PROFEC) and free energy perturbation methods were employed to suggest the modifications that may improve the stability of a mutant T4 lysozyme with a S-2-amino-3-cyclopentylpropanoic acid residue (Cpe) at position 133. The free energy derivatives and PROFEC methods were used to locate promising sites where modifications may be introduced. The effects of several candidate modifications on the enzyme's stability were analyzed by the free energy perturbation method. We found that this scheme is able to effectively suggest modifications that may increase the enzyme's stability. The modifications investigated are the introduction of a methyl, a tert-butyl or a trifluoromethyl group at the Cϵ2 position and a cyclopropyl group between the Cδ2 and Cϵ2 position on the cyclopentyl ring. The stereochemistry of the introduced groups (in the α or β configurations) was studied. Our calculations predict that the introduction of a methyl group in the α configuration or a cyclopropyl group in the β configuration will increase the stability of the enzyme; the introduction of the two groups in the other configurations and the other modifications will decrease the stability of the enzyme. The results indicate that packing interactions can strongly influence the stability of the enzyme. Proteins 32:438–458, 1998. © 1998 Wiley-Liss, Inc.  相似文献   
346.
Levels of enolase isozymes (alpha alpha, alpha gamma, and gamma gamma forms) and S-100 protein in rat sciatic nerves were determined during their degeneration and regeneration processes. The sciatic nerves were unilaterally crushed or severed. The rats were killed 1, 2, 6, and 8-9 weeks later, and both the proximal and distal portions of the damaged nerves were dissected. Control samples were obtained from the untreated contralateral hindlimbs. Enolase isozymes and S-100 protein in the nerve segments were determined with the enzyme immunoassay method. The control nerves contained about 40, 90, and 30 pmol/mg protein of alpha alpha, alpha gamma, and gamma gamma enolases, respectively, and 0.85 microgram/mg protein of S-100 protein. These levels were not affected by repetitive electrical stimulation of the nerve fibers in vivo. The levels of the nervous system-specific forms of enolase (alpha gamma and gamma gamma) and S-100 protein decreased markedly within a week in the distal portion of the crushed nerve (alpha gamma, 27 pmol/mg; gamma gamma, 5.5 pmol/mg; S-100 protein, 0.36 microgram/mg) with apparently no change in the concentration of alpha alpha enolase. These levels in the proximal portion of the crushed nerve remained unaltered. The sensory and motor functions impaired by the sciatic nerve crush showed a recovery more or less after 4-9 weeks. This recovery was accompanied by a gradual regaining of the specific proteins in the distal portion of injured nerves (alpha gamma, 64 pmol/mg; gamma gamma, 13 pmol/mg; S-100 protein, 0.63 microgram/mg at the 8-9th week).  相似文献   
347.
The problem of nonspecific adsorption to the reversibly soluble-insoluble polymers is of considerable importance in the design of an affinity precipitation protocol. It was seen that activation and coupling of the affinity ligand to the polymer changes the nature of the polymer surface in a significant fashion. The results with pure trypsin, partially purified trypsin preparation, and crude protein extract-containing protein inhibitors of trypsin and α-amylase and the reversibly soluble-insoluble polymer Eudragit S-100, show that nonspecific adsorption may not be a severe limitation in such systems.  相似文献   
348.
The calcium-binding protein S100B binds to several potential target proteins, but there is no detailed information showing the location of the binding site for any target protein on S100B. We have made backbone assignments of the calcium-bound form of S100B and used chemical-shift changes in spectra of 15N-labeled protein to locate the site that binds a peptide corresponding to residues 265-276 from CapZ alpha, the actin capping protein. The largest chemical-shift changes are observed for resonances arising from residues around the C terminus of the C-terminal helix of S100B and residues Val-8 to Asp-12 of the N-terminal helix. These residues are close to but not identical to residues that have been identified by mutational analysis to be important in other S100 protein-protein interactions. They make up a patch across the S100B dimer interface and include some residues that are quite buried in the structure of calcium-free S100B. We believe we may have identified a binding site that could be common to many S100 protein-protein interactions.  相似文献   
349.
Letter: Troponin subunit interactions   总被引:5,自引:0,他引:5  
Subunit interactions of the troponin complex are displayed by the in vitro aggregates formed by tropomyosin and the components of troponin. Certain linkages are specifically affected by calcium. These findings are consistent with a simple steric scheme for the functioning of the complex.  相似文献   
350.
Estrogen-activated sexual behavior in male rats   总被引:1,自引:1,他引:0  
Daily injections of 100 μg estradiol benzoate activated the whole pattern of sexual behavior in castrated sexually experienced male rats. If compared to rats treated daily with 100 μg testosterone propionate, the estrogen-treated males tended to have longer latencies and more mounts and intromissions prior to ejaculation. Fifty micrograms of estradiol benzoate stimulated the display of mounts and intromissions in prepuberally castrated male rats. No peripheral effects of the estrogen treatment were noted. These results suggest that estrogen has central “androgen-like” effects, but no such effects in the periphery. Estrogen treatment (5, 50, and 200 μg/kg for 3 weeks) of intact sexually experienced male rats resulted in testicular atrophy and loss of body weight, but had no significant effects on the sexual behavior.  相似文献   
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