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91.
细胞核因子NF-кB在肿瘤血管生成中可能具有核心调节作用,本文选择80例有随访结果的骨肉瘤,应用免疫组化方法检测 NF-кB p65亚单位以及血管内皮细胞生长因子(VEGF)的表达,同时观察肿瘤内微血管密度(MVD),旨在探讨 NF-кB表达与骨肉瘤血管生成的关系。结果:80例骨肉瘤中 48例 NF-кB p65阳性,阳性产物主要定位于肿瘤细胞浆。NF-кB表达与VEGF表达和MVD呈显著正相关,而且NF-кB阳性组病人存活时间显著低于阴性组。该结果表明:①NF-кB p65是骨肉瘤相关的一种癌蛋白,在骨肉瘤的发生和发展中发挥重要的作用;②NF-кB对VEGF可能有正向调节作用,进而影响骨肉瘤血管生成;③NF-кB 对肿瘤血管生成的作用,可能是影响骨肉瘤预后的主要原因之一。  相似文献   
92.
目的 :ABO亚型在临床输血中经常造成错定血型及输血反应 ,因而研制抗A1试剂血清是解决ABO亚型鉴定的主要途径。方法 :采用血型血清学特异性抗原抗体吸收实验。结果 :经大量反复实验 ,研制出特异性强 ,效价符合要求的抗A1试剂血清。结论 :抗A1血清是鉴定A亚型的专用试剂血清 ,对临床鉴定ABO亚型及安全输血有实用意义。  相似文献   
93.
目的:观察蓖麻油餐用于晚期妊娠引产的疗效。方法:随机选择118例服用蓖麻油餐引产与同期106例催产素引产作对照,观察引产效果、产程、产后出血及新生儿评分。结果:观察组引产效率明显高于对照组(P<005),剖宫产率明显低于对照组(P<005),两组的产后出血和新生儿阿氏评分无显著性差异(P>005)。结论:蓖麻油引产优于催产素引产。  相似文献   
94.
采用细胞生物学方法测定类风湿性关节炎( R A)14 例血清 I L- 6 、 T N F 水平,均显著高于正常对照组( P< 0 .001) 。相关分析显示 I L- 6 与 T N F 水平变化呈正相关( P< 0 .01) , I L- 6 、 T N F 与血沉亦呈正相关( P<0 .05) 。认为, I L- 6 、 T N F 参与 R A 的发病,两者在致病中有协同相同;其水平变化与 R A 的活动性及血沉相关。  相似文献   
95.
In 1978, China decided to reform its economy and since then has gradually opened up to the world. The economy has grown rapidly at an average of 9.8% per year from 1978 to 1994. Medical expenditure, especially for drugs, has grown even more rapidly. The increase in medical expenditure can be attributed to changing disease patterns, a higher proportion of older people in the population and fee-for-service incentives for hospitals. Due to the changing economic system and higher cost of health care, the Chinese government has reformed its health care system, including its health and drug policy. The drug policy reform has led to more comprehensive policy elements, including registration, production, distribution, utilization and administration. As a part of drug policy reform, the drug distribution network has also been changed, from a centrally controlled supply system (push system) to a market-oriented demand system (pull system). Hospitals can now purchase drugs directly from drug companies, factories and retailers, leading to increased price competition. Patients have easier access to drugs as more drugs are available on the market. At the same time, this has also entailed negative effects. The old drug administrative system is not suitable for the new drug distribution network. It is easy for people to get drugs on the market and this can lead to overuse and misuse. Marketing factors have influenced drug distribution so strongly that there is a risk of fake or low quality drugs being distributed. The government has taken some measures to fight these negative effects. This paper describes the drug policy reform in China, particularly the distribution of drugs to health care facilities.  相似文献   
96.
Manufacture of VAQTA, an inactivated hepatitis A virus vaccine, includes extensive purification of the intact virus particle to remove endogenous components from the host cell culture lysate as well as compounds introduced in the upstream purification process. Analysis of the final purified hepatitis A virus product by SDS-PAGE prior to inactivation shows that greater than 95% of the protein in the preparation is found in four protein bands, which have been confirmed to be hepatitis A virus capsid proteins VP0, VP1, VP2 and VP3 based on Western blot and mass spectrometry analyses. Validation of the manufacturing process and direct analysis of the final product were used to demonstrate that no other specific host cell-derived components are detected and that process residuals are all below the limits of detection of the assays used. Establishment of a rigorous standard of high purity for this product was pursued to minimize the impact of impurities during clinical development of this product and will facilitate the incorporation of this product into combination vaccines.  相似文献   
97.
针对用于上海污水外排的黄浦江底隧道工程,通过土工离心模拟试验,探讨了上海粘土的成拱能力.对于无支护的情况,开挖双孔隧道时,洞底以上约8 m厚的灰色砂质粉土或粘土中不能形成稳定的天然拱.进一步研究表明,该层土所需的成拱厚度至少为12 m;对于有混凝土管支护的情况,由于支护刚度较大,管顶上土压力基本上等于管顶以上土层的自重应力.  相似文献   
98.
Cytotoxicities of four urushiols, congeners isolated from the sap of Korean lacquer tree (Rhus vernicifera Stokes), to 29 human cancer cell lines originated from 9 organs were evaluated. Their values of 50% growth inhibition were below 4 microg/ml, and showed cell line specific cytotoxicity. The present result is the first report on the cytotoxicity of urushiols suggesting that they would have an anticancer activity to human cancer cells.  相似文献   
99.
Tissue sections taken from 157 potentially curatively operated lung carcinoma patients (70 epidermoid carcinomas, 68 adenocarcinomas, 15 large cell anaplastic, and 4 small cell anaplastic carcinomas) were examined by a standardized histochemical protocol in a prospective study evaluating the extent of various types of probes to serve as prognostic indicators in lung cancer. Detailed clinical records and survival data (minimum 56 weeks, maximum 96 weeks) were correlated to the results of the histochemical reactions. The study centres on monitoring the expression of galactoside-containing epitopes in tumor cells by human, animal and plant lectins: and with a monoclonal antibody. In addition, affinity-purified subfractions of natural antibodies from human serum with preferential affinity to alpha- and beta-galactosides, respectively, were employed. Significant contributions to the estimation of the survival of patients are given by clinical parameters (pT, pN stage), number of resected and positive lymph nodes and presence of tumor metastases into specific lymph nodes (No. 5 and No. 6 right and left). With respect to the relevance of subsets of beta-galactosides, the galectin from chicken liver (CL-16) and the Le(y)-specific monoclonal antibody unveiled a negative correlation at a statistically significant level. The predictive value of binding of the animal lectin CL-16 was especially pronounced for patients with advanced tumor stages, pointing to a potential role of such lectin-reactive beta-galactosides in late tumor stages or progression.  相似文献   
100.
Biochemical and metabolic indicators were monitored in a group of volunteers suffering from a variety of chronic illnesses participating in a week's course on a special uncooked vegetable diet, known as "living food". Unmatched healthy controls ate the same diet cooked for 2 min in a microwave oven. After 1 week on the regimen, serum protein and urea contents decreased and alanine aminotransferase (ALAT) activity increased in both groups, although all within the normal range. Blood glucose increased in both groups to slightly above normal limits but total serum cholesterol dropped about 1 mmol/l from normal starting levels. Serum tocopherol and retinol increased only in the group eating the uncooked diet. In both groups urinary sodium dropped drastically without a significant change in potassium. Serum and urinary phenol and p-cresol diminished also significantly. It is concluded that this vegetable diet may be of some benefit in the short term but any longer-term use requires evaluation.  相似文献   
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