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61.
Optimum conditions of chiral derivatization reaction of beta-blockers acebutolol, arotinolol, beta-xolol, bisoprolol, celiprolol, metoprolol and pindolol) with (-)-menthyl chloroformate were investigated for the resolution by HPLC. With more than 30 times molar excess of (-)-menthyl chloroformate chiral derivatization reactions were completed within one hour at room temperature except arotinolol and celiprolol. Diastereomeric derivatives of beta-blockers were well resolved on the ODS column using acetonitrile-methanol-water as a mobile phase. 相似文献
62.
Jae Chul Jung Ju Cheun Kim Oee Sook Park Bong Suek Jang 《Archives of pharmacal research》1999,22(3):302-305
An efficient procedure for the preparation of 4-hydroxy-3-{1,2,3,4-tetra-hydro-3-[4-(4-triflu-oromethylbenzyl oxy)phenyl]-1-naphthyl}thiocoumarin (thioflocoumafen, 1a and 1b) is described. The key step in the synthesis involves the condensation reaction of 3-(4-methoxyphenyl)-1-tetralol (2) with 4-hydroxy-1-thiocoumarin (3). 相似文献
63.
Byong Kak Kim Eung Chil Choi Kyeong Soo Chung Hee Ju Park Hye Ryoung Kim Yang Sup Kim Yong Hwan Park Mi Ja Shim 《Archives of pharmacal research》1983,6(2):141-142
To find antitumor metabolites in Korean basidiomycetes, the shake-cultured mycelia of eight of the higher fungi were extracted with hot water and the extracts, after being partially purified, were subjected toin vivo antitumor test. When administeredi.p. at the dose of 30mg/kg/day for ten consecutive days into the female ICR mice, which had been implanted with 1×105 cells of sarcoma 180 twenty-four hours before the first injection, the extracts ofAgaricus campestris, Lyophyllum decastes, Lyophyllum ulmarium, Armillaria tabescence andCalvatia exipulitormis respectively showed inhibition ratios of 64.1%, 65.4%, 60.0%, 53.0% and 49.3%. These five species were selected for further study, whereas the extracts ofPhallus impudicus, Coprinus comatus andPholiota squarrosa which showed the inhibition ratios of 31.2%, 33.5% and 19.0% were discontinued. 相似文献
64.
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
65.
Selective neuronal survival and upregulation of PCNA in the rat inner retina following transient ischemia 总被引:1,自引:0,他引:1
Ju WK Kim KY Hofmann HD Kim IB Lee MY Oh SJ Chun MH 《Journal of neuropathology and experimental neurology》2000,59(3):241-250
In this study we investigated the extent and time course of neuronal cell death and the regulation of the proliferating cell nuclear antigen (PCNA) in the different retinal cell layers following ischemia-reperfusion injury. Retinal ischemia was induced by controlled elevation of the intraocular pressure for a duration of 60 min. Changes in thickness and cell numbers in the retinal cell layers were analyzed at various time points (1 h to 4 weeks) after reperfusion. In parallel, apoptotic cell death was determined by the TUNEL method and the expression of PCNA analyzed by immunocytochemistry. In addition, we tested whether PCNA is expressed in neurons by double immunocytochemistry. The reduction in thickness was found to be less pronounced in the inner nuclear layer (INL). Correspondingly, cell numbers decreased by only 33% in the inner retina, but by more than 80% in the outer nuclear layer (ONL). Alterations in glial cell numbers did not contribute significantly to postischemic changes in the INL and ONL as assessed by using immunocytochemical markers for microglial and Müller cells. The time course of cell death determined by the TUNEL technique also differed markedly in the retinal layers being rapid and transient in the inner retina but delayed and prolonged in the ONL. PCNA immunoreactivity was undetectable in the normal retina, but was specifically induced in neurons of the inner retina within 1 h after reperfusion and was sustained for at least 4 weeks. We conclude that in contrast to photoreceptors in the ONL, a significant proportion of inner retinal neurons is resistant to ischemic insult induced by transiently increased intraocular pressure and that PCNA may possibly play a role in the selective postischemic survival of these cells. 相似文献
66.
67.
目的:探讨经鼻持续气道正压通气(nCPAP)治疗,对阻塞性睡眠呼吸暂停综合征(OSAS)合并高血压患者动态血压的影响。方法:22例男性患者行多导睡眠图(PSG)监测及动态血压检查确诊为OSAS合并高血压的患者,观察nCPAP治疗前后患者动态血压、多导睡眠图等多项指标变化。结果:nCPAP治疗后患者PSG参数明显改善:睡眠时最低SaO_2从(71.0±12.3)%上升到(91.7±7.3)%(P<0.01);RDI显著降低;同时24小时血压明显下降,治疗前血压(16.5±1.6/11.6±2.3Kpa),治疗后血压(13.7±1.5/9.3±1.4Kpa)(P<0.01)。结论:经鼻持续气道正压通气治疗阻塞性睡眠呼吸暂停综合征,不但可以纠正患者的呼吸暂停,改善临床症状,而且可能降低患者的血压。 相似文献
68.
69.
土鳖虫水提物对实验性高脂血症大鼠血管内皮和内皮素的影响 总被引:19,自引:0,他引:19
目的研究土鳖虫水提物对高脂血症大鼠血管内皮和内皮素 (ET)的影响。方法建立高脂血症大鼠模型 ,测定血浆ET的浓度 ,并应用内皮细胞铺片和免疫组化相结合的方法 ,在大鼠主动脉内皮细胞铺片上 ,计数内皮细胞和ET阳性细胞并定量分析ET的合成。结果实验第 80d ,与正常组比较 ,高脂组血浆ET显著增高 (P <0 .0 1) ;内皮铺片显示内皮细胞数量增多 ,排列紊乱 ,胞核大小和染色深浅不一 ,ET阳性细胞率显著升高 (P <0 .0 1)。土鳖虫中、高剂量组血浆ET水平和ET阳性细胞率显著降低 (P <0 .0 5~ 0 .0 1)。结论土鳖虫水提物能保护血管内皮 ,减少ET的合成与释放 相似文献
70.
Effect of lonizing Radiation on the Expression of p16,CyclinD1 and CDK4 in Mouse Thymocytes and Splenocytes 总被引:4,自引:0,他引:4
OBJECTIVE: To investigate the effect of ionizing radiation on the expression of p16, CyclinD1, and CDK4 in mouse thymocytes and splenocytes. METHODS: Fluorescent staining and flow cytometry analysis were employed for the measurement of protein expression. RESULTS: In time course experiments, it was found that the expression of p16 protein was significantly increased at 8, 24, and 48 h for thymocytes (P < 0.05, P < 0.01, and P < 0.05, respectively) and at 24 h for splenocytes (P < 0.05) after whole body irradiation (WBI) with 2.0 Gy X-rays. However, the expression of CDK4 protein was significantly decreased from 8 h to 24 h for thymocytes (P < 0.05-P < 0.01) and from 8 h to 72 h for splenocytes (P < 0.05-P < 0.01). In dose effect experiments, it was found that the expression of p16 protein in thymocytes and splenocytes was significantly increased at 24 h after WBI with 1.0, 2.0, and 4.0 Gy (P < 0.05-P < 0.01), whereas the expression of CDK4 protein was significantly decreased with 2.0 Gy for thymocytes (P < 0.05) and 0.5-6.0 Gy for splenocytes (P < 0.05-P < 0.01). Results also showed that the expression of CyclinD1 protein decreased markedly in both thymocytes and splenocytes after exposure. CONCLUSION: The results indicate that the expression of p16 protein in thymocytes and splenocytes can be induced by ionizing radiation, and the p16-CyclinD1/CDK4 pathway may play an important role for G1 arrest of thymocytes induced by X-rays. 相似文献