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111.
Posthypoxic myoclonus and seizures precipitate as secondary neurological consequences in ischemic/hypoxic insults of the central nervous system. Neuronal hyperexcitation may be due to excessive activation of glutamatergic neurotransmission, an effect that has been shown to follow ischemic/hypoxic events. Therefore, riluzole, an anticonvulsant that inhibits the release of glutamate by stabilizing the inactivated state of activated voltage-sensitive sodium channels, was tested for its antimyoclonic and neuroprotective properties in the cardiac arrest-induced animal model of posthypoxic myoclonus. Riluzole (4-12 mg/kg i.p.) dose-dependently attenuated the audiogenic seizures and action myoclonus seen in this animal model. Histological examination using Nissl staining and the novel Fluoro-Jade histochemistry in cardiac-arrested animals showed an extensive neuronal degeneration in the hippocampus and cerebellum. Riluzole treatment almost completely prevented the neuronal degeneration in these brain areas. The neuroprotective effect was more pronounced in hippocampal pyramidal neurons and cerebellar Purkinje cells. These effects were seen at therapeutically relevant doses of riluzole, and the animals tolerated the treatment well. These findings indicate that the pathogenesis of posthypoxic myoclonus and seizure may involve excessive activation of glutamate neurotransmission, and that riluzole may serve as an effective pharmacological agent with neuroprotective potential for the treatment of neurological conditions associated with cardiac arrest in humans.  相似文献   
112.
目的:观察新型电热手术刀在妇产科手术中的应用效果。方法:对65 例需手术的妇产科病人,用新型电热手术刀做手术,与同期用普通手术刀(25 例) 和高频电刀(20 例) 做手术进行比较。结果:电热手术刀可在锋利切割组织的同时快速止血,止血作用类似于高频电刀;和普通手术刀相比,电热手术刀能明显减少出血量,加快手术速度,且无脂肪液化,无刀片粘连,切口愈合良好,热损伤轻微。结论:电热手术刀结合了普通手术刀和高频电刀的优点,适合在妇产科手术中推广使用。  相似文献   
113.
研究了不同冷冻与复苏方法以及不同移植周期法对人类胚胎冻存结果的影响。共复苏了149 个胚胎,89 个(59.7% )得以存活。在20 个移植周期中,5 例(25.0% )获得临床妊娠,2 例已经分娩健康的婴儿。结果表明,采用缓慢降温至- 120℃再浸入液氮中冷冻及快速升温、逐步置换冷冻保护剂的方法复苏,胚胎的存活率(72.7% )较高,但不同移植周期对冻胚移植的临床妊娠情况影响不大  相似文献   
114.
用HPLC法测定蒲公英中咖啡酸和绿原酸的含量。采用 HP Hypersil C_18色谱柱,200 mmx 2. 1mm,5μm,流动相:甲醇-磷酸盐缓冲溶液(pH=4. 2) 23: 77,检测波长:323 nm,柱温:40℃,流速:1.0 mL/min。该法咖啡酸平均回收率 99.80%,RSD 2.14%;绿原酸平均回收率99.54%,RSD 2.69%。本法稳定可靠,为药典建立蒲公英药材的质量标准提供了依据。  相似文献   
115.
显性遗传性运动感觉性神经病Ⅱ型一个家系分析   总被引:1,自引:0,他引:1  
目的本文报道一个在老年期发病的遗传性运动感觉性周围神经病Ⅱ型家族。方法对家族成员进行临床和电生理检查,其中1例病人进行腓肠神经活检。结果家族成员在老年期出现四肢无力和感觉减退。老年病人和无症状年轻病人的电生理检查均发现周围神经的诱发电位波幅显著下降。腓肠神经活检证实轴索性周围神经病。结论检查结果符合显性遗传性运动感觉性周围神经病Ⅱ型的诊断,电生理检查可以发现家族中的亚临床病人。  相似文献   
116.
Seo KK  Yun HY  Kim H  Kim SC 《Journal of andrology》1999,20(2):298-306
The present study was designed to evaluate whether functional impairment and/or protein expression of constitutive nitric oxide synthase (cNOS; endothelial NOS [eNOS] and neuronal NOS[nNOS]) was involved in impairment of endothelium-dependent relaxation of cavernous smooth muscle in hypercholesterolemic rabbits. New Zealand White rabbits were randomly divided into control and experimental groups. The control group (n=20) received a regular diet, while the two experimental groups (n=20 for each) were fed a 2% cholesterol diet for 4 and 8 weeks, respectively. We conducted isometric tension studies with endothelium-dependent and endothelium-independent vasodilators with or without preincubation with L-arginine and nonadrenergic, noncholinergic (NANC)-selective electrical field stimulation on isolated strips of corpus cavernosum. Expression of cNOS (eNOS and nNOS) protein was assessed by Western blot analysis. cNOS activities in both cytosolic and particulate fractions were measured by determining the conversion of L-[U-14C] arginine to L-[U-14C] citrulline. Blood levels of cholesterol were significantly higher (P < 0.01) in the experimental groups than in the control group. The relaxation responses to endothelium-dependent agents (acetylcholine and adenosine 5'-diphosphate [ADP]) were significantly reduced (P < 0.05) in both experimental groups, regardless of their incubation with L-arginine, compared with the control group. However, no differences were found among the three groups in the relaxation response to endothelium-independent agents (papaverine and nitroprusside) and to NANC-selective electrical field stimulation. There was no difference in immunoreactive nNOS from cytosolic and particulate fractions between the cavernous tissues of the control and experimental groups. nNOS protein levels in the particulate fractions were markedly lower than in the cytosolic fractions. The particulate cNOS activity was significantly decreased (P < 0.05) in the experimental groups compared with the control group, while the cytosolic cNOS activity in the experimental groups was not different from that found in the control group. Therefore, it is concluded that functional impairment of eNOS, rather than of nNOS, may lead to impairment of cavernous smooth muscle relaxation in response to endothelium-mediated stimuli in hypercholesterolemic rabbits.  相似文献   
117.
Lee SJ  Yun YS  Lee IK  Ryoo IJ  Yun BS  Yoo ID 《Planta medica》1999,65(7):658-660
A new lignan named as hibiscuside, (+)-pinoresinol 4-O-[beta-glucopyranosyl (1--->2)-alpha-rhamnoside] (1), and a known lignan, syringaresinol (2) were isolated from the root bark of Hibiscus syriacus together with two feruloyltyramines (3,4) and three known isoflavonoids (5,6,7). The structures of these compounds have been established on the basis of their NMR, mass UV spectra. Among these phenolic compounds, 6"-O-acetyldaidzin (5), 6"-O-acetylgenistin (6), and 3-hydroxydaidzein (7) with IC(50) values of 8.2, 10.6, and 4.1 microM, respectively, significantly inhibited lipid peroxidation in rat liver microsomes. Hibiscuside (1), E- and Z-N-feruloyl tyramines (3,4) exhibited moderate antioxidant activity.  相似文献   
118.
The mammary gland is a hormone-target organ derived from epidermis and develops as a result of reciprocal mesenchymal-epithelial interactions. The induction of mammary differentiation from indifferent epidermal cells by mammary mesenchyme implies induction of the complement of hormone receptors characteristic of normal mammary epithelium in cells of the epidermis. Considering the facts that mammary epithelial differentiation is induced by mammary mesenchyme and that certain aspects of hormone response (androgen-induced mammary regression) are inextricably linked to mesenchymal-epithelial interactions, it is evident that the biology of the mammary gland arises from and is maintained via cell-cell interactions. As a corollary, perturbation of stromal-epithelial interactions in adulthood may play a role in mammary carcinogenesis and in turn may provide opportunities for differentiation therapy.  相似文献   
119.
Corneal permeability of variousn-alkylp-hydroxybenzoates (parabens) was studiedin vitro using excised rabbit corneas, and the effect of lipophilicity of parabens on the corneal permeability was also investigated. Permeability coefficients were obtained from the least-square linear regression after the steady state had been reached. Lipophilicity of parabens was calculated by distribution coefficients determined in octanol-S \(12_\phi [\kern-0.15em[ \) rensen’s buffer solution (pH 5.0). The relationship between lipophilicity and corneal permeability of parabens was not linear, but the optimum lipophilicity for the maximum permeation was found. The influence of tween 80 on corneal permeability of methyl and butylparaben was not significant.  相似文献   
120.
Z M Gao  Z C Fan  Y Yun 《中西医结合杂志》1991,11(4):206-8, 196
This article reports the child reversal respiratory tract infection treated with Feibao syrup which produced in accordance with the TCM theory of "the evil factor can't attack the body with vital-Qi" and "the evil factor will attack the body which vital-Qi is weak". Feibao syrup consisted of Radix Astragali, Herba Hedyotis diffusae, etc. The clinical research proved that after taking the medicine, the general condition, appetite and anemia were improved, the profuse sweating disappeared, the tolerance against cold was improved, the frequency of occurrence of the disease was decreased or ceased. Even if the disease occurred, the symptoms were mild, the disease course was short. The efficacy of the medicine was 95.2%. It was better than that of levamisole (78.6%), P less than 0.05. This medicine can obviously improve the level of serum IgA and the cellular immunity (P less than 0.01). The experiment on mice manifested that it could obviously enhance the macrophage phagocytic rate, lymphocyte transformation rate, EAC rosette forming rate, and hemolysin generating rate.  相似文献   
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