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61.
The transforming growth factors type beta 1, beta 2, and beta 1.2 suppress multidrug transport in human pat-1 glioblastoma cells and even in cells that strongly over-express mdr genes and are resistant to inhibition of multidrug transport by chemosensitizers. Thus, inhibition of multidrug transport by cytokines might be a new approach to increase cellular accumulation of chemotherapeutic agents in multidrug resistant glial tumor cells. Interestingly, a member of the more distantly related decapentaplegic subgroup of transforming growth factors, the bone morphogenetic protein BMP 2, did not inhibit multidrug transport.  相似文献   
62.
63.
蛇床子水提取液抑瘤作用的实验研究   总被引:13,自引:0,他引:13  
目的 :研究蛇床子水提取液的体内抗肿瘤作用。方法 :通过 S180 肉瘤移植建立荷瘤小鼠模型 ,给予不同剂量蛇床子水提取液后观察 S180 荷瘤小鼠肿瘤生长曲线、血清唾液酸 (SA)、瘤重及小鼠生存天数的变化。结果 :蛇床子水提取液能明显抑制肿瘤生长 ,降低荷瘤小鼠血清 SA水平 ,0 .0 6mg/(g· d) ,0 .1 1 mg/(g· d)、0 .2 1 mg/(g· d)剂量组平均瘤重低于肿瘤对照组 (P<0 .0 5 ) ,抑瘤率依次为 2 3 .2 %、2 9.1 %和 2 4 .8%,且能延长荷瘤小鼠生存天数 (P<0 .0 1 ) ,动物生命延长率依次为 :2 6 .9%、3 4 .8%和 2 6 .6 %。结论 :蛇床子水提取液具有较强的抗肿瘤效应 ,有很好的利用前景 ,值得对其进行深入研究。  相似文献   
64.
The polymorphism at the HLA-DPB1 locus has been characterized in a large number of patients with multiple sclerosis (n = 112) and in healthy controls (n = 115). Both patients and controls lived in the southwest of France (in the Pyrénées Atlantiques) and had similar ethnic background. The typing procedure involved the selective amplification of the second exon of the DPB1 locus by polymerase chain reaction, followed by hybridization of the amplified DNA with 14 sequence-specific oligonucleotide probes. Individual alleles were identified by the pattern of hybridization of the different probes. The distribution of the DPB1 alleles was not significantly different in multiple sclerosis patients and controls (p = 0.11). This does not corroborate the reported association of multiple sclerosis with the primed lymphocyte typing (PLT)-defined DPw4 specificity and is not in favour of a role played by polymorphic residues of the DP molecule in susceptibility to multiple sclerosis.  相似文献   
65.
Permissive herpes simplex virus (HSV) infection in tissue culture results in host cell destruction. Latent HSV infection in vivo occurs in neurons of peripheral sensory ganglia (PSG) and it therefore can not take place in neurons in which the virus has completed a lytic replication cycle similar to that present in vitro. Our hypothesis, based on experimental data and observations in humans, suggests that establishment of latent infection and reactivation of HSV-1 does not involve neuronal cell loss. Latency is established in neurons in which the virus does not replicate and is determined, in part, by the tissue levels of a herpes transactivating protein (Vmw65) that is a component of the viral tegument. We also suggest that reactivation of latent infection does not involve destruction of neurons and is due to replication of virus at the peripheral mucocutaneous tissues to where virus or viral DNA have been transported from the nervous tissue. Alternatively, reactivation is initiated in the PSG using a replication cycle which does not involve irreversible damage to neurons. This model explains the lack of damage to neurons which continue to serve as permanent reservoirs of latent virus for the entire life of the host.  相似文献   
66.
[(1R)‐endo]‐(+)‐3‐bromocamphor was dehalogenated with tritium gas to [3‐3H]camphor and via [3‐3H]phenylborneol converted to [3‐3H]deramciclane isolated as the fumarate salt (specific activity 51.8 GBq/mmol). This three step synthesis from [3‐3H]camphor gave an overall yield of 22%. Benzyloxy‐acetic acid methyl ester was reduced with sodium‐borotritide to 2‐benzyloxy‐ethanol‐[1‐3H], and through a four step procedure was converted to 2‐dimethylaminoethyl‐[2‐3H] chloride. The latter was condensed with the sodium derivative of 2‐phenylborneol giving rise to [2‐dimethylamino‐[2‐3H]ethoxy]deramciclane isolated as the fumarate (specific activity 8.177 GBq/mmol). This six step synthesis from [3H]NaBH4 gave an overall yield of 6%. Copyright © 2005 John Wiley & Sons, Ltd.  相似文献   
67.
The effect of interleukin-1 on iron metabolism in rats was evaluated. Plasma iron decreased from 184 +/- 16 micrograms/dl (mean +/- SE) to 24 +/- 12 at 6 hours after interleukin-1 intramuscular administration in non-fasting rats and 109 +/- 6 micrograms/dl to 12 +/- 1 micrograms/dl in fasting rats, which was significantly lower than in control rats. Ferrokinetic studies showed a more rapid disappearance rate and lower iron turnover in interleukin-1-injected rats. The release of iron from the mononuclear phagocyte system to plasma was studied at 3 h after interleukin-1 administration. Although the percent of radioactivity in plasma of the total injected dose was 3.2 +/- 0.6% in interleukin-1, which was significantly lower than in the control rats (5.4 +/- 0.6%) at 9 h after intravenous injection of 59Fe chondroitin ferrous sulfate, there was no difference between the amount of 59Fe released from the mononuclear phagocyte system over the first 9 h in interleukin-1 and control rats. These data appear to imply that iron release is unimpaired but that, for some reason, there is an enhanced rate of clearance of the 59Fe once it has been released from the mononuclear phagocyte system into the plasma.  相似文献   
68.
黄顺祥  刘配芬 《中国保健》2007,15(20):99-100
目的比较小儿支气管哮喘中、西医治疗疗效.方法将64例支气管哮喘患儿随机分为两组治疗组32例,给予常规西药治疗及对症处理;中药组32例,在常规西药治疗的基础上加服中药(补益脾肾方),监测两组的ET-1、NO水平,比较两组的临床疗效.结果急性期ET-1、NO显著增高,入院时两组比较,差异无显著性(P>0.05).治疗2w后,中药组ET-1、NO明显下降,两组比较,差异有显著性(P<0.05).1年后随访患儿中,中药组(23例)轻度哮喘2例,中度哮喘3例,重度哮喘2例;治疗组(20例)依次分别为5例、4例、4例;1年内中药组与治疗组患儿哮喘发作次数比较未发作(例)61,发作>3次(例)15,两组比较差异有显著性(P<0.01).结论补益脾肾中药可降低支气管哮喘患儿的血ET-1、NO水平,减轻哮喘发作时的症状;随访1年患儿哮喘发作次数明显减少.我们认为补益脾肾中药可提高支气管哮喘患儿的机体抵抗力,减轻气管炎症损伤,对防治小儿支气管哮喘有效.  相似文献   
69.
目的:分析T1期(肿瘤直径<2cm)原发性乳腺癌女性患者绝经前后在肿瘤大小、病理分类、淋巴结转移率和数目。方法:常规病理检验以及应用免疫组化、HE法分别测定绝经前乳腺癌患者和绝经后乳腺癌患者者的ER、PR。结果:两组患者在肿瘤大小上无明显差异,但绝经前乳腺癌患者浸润导管癌的百分比为 84. 7%,绝经后乳腺癌患者的浸润导管癌百分比为 62. 2%,经χ2 检验,P<0. 01。两组淋巴结转移率分别为 39. 3%和 25. 5%,经χ2 检验,P<0. 01。两组ER和PR阳性伴淋巴结转移的比例经χ2 检验,P<0. 05。结论:绝经前乳腺癌患者和绝经后乳腺癌患者在病理分类、淋巴结转移率及数目、ER、PR阳性伴淋巴结转移上有显著性差异。对于T1原发性乳腺癌患者不论有无淋巴结转移,均应行癌肿切除伴Ⅰ、Ⅱ级淋巴结清扫。  相似文献   
70.
研究亚硫酸氢钠和氯化钠配伍使用的增敏性,建立了NaHSO3—NaCl—KIO3—KI四元无机体系测定碘盐中碘含量的新方法。测定碘的最佳条件:磷酸介质,pH 3~4,最大吸收波长479 nm,ε479=1.5×105L/(mol/cm),碘含量(以KIO3中I计)在0~2.24mg/L内符合比尔定律。用于测定食盐中碘的含量,回收率为99.49%~101.3%,结果满意。  相似文献   
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