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951.
Worldwide, two billion people have at some time been infected by hepatitis B virus, 370 millions suffer from chronic infection and around one million die each year from HBV-related liver diseases of which liver cancer is the ultimate stage. Vaccination is the measure that is most effective in reducing the global incidence of hepatitis B and hepatitis B vaccines have now been available for over 20 years. The first hepatitis B vaccine was prepared from inactivated hepatitis B surface antigen particles purified from plasma of asymptomatic carriers of hepatitis B virus. Knowledge of the structure and genomic organization of hepatitis B virus has led to development of the first DNA recombinant vaccine. In preventing hepatocellular carcinoma development, hepatitis B virus vaccines are considered as the first available cancer vaccine. HBV vaccines have recently taken on a new role as therapeutic vaccines as an attempt to cure or to control hepatitis B virus infection in persistently infected individuals.  相似文献   
952.
953.
Methylglyoxal (MG) is a metabolite of glucose. The serum MG level is increased in diabetic patients, and MG is implicated in diabetic complications related to embryonic development injury. We previously reported cytotoxic effects of MG on mouse embryonic stem cells and blastocysts, and a further association with defects in subsequent development. Here, we further investigate the effects of MG on oocyte maturation and subsequent pre- and post-implantation development, both in vitro and in vivo. Notably, MG induced a significant reduction in the rate of oocyte maturation, fertilization, and in vitro embryonic development. Treatment of oocytes with MG during in vitro maturation (IVM) led to increased resorption of post-implantation embryos and decreased fetal weight. Experiments with an in vivo mouse model disclosed that consumption of drinking water containing 10–20 μM MG led to decreased oocyte maturation and in vitro fertilization, as well as early embryonic developmental injury. Finally, pretreatment with a caspase-3-specific inhibitor effectively prevented MG-triggered injury effects, suggesting that embryo impairment by MG occurs via a caspase-dependent apoptotic process.  相似文献   
954.
955.
目的 评价低剂量辐射对恶性肿瘤患者免疫功能的影响。方法 将20例患者(其中非何杰金氏淋巴瘤13例、小细胞肺癌7例)随机分为两组:HBR组和RR组。其中HBR组10例患者采用常规放疗(RR)加低剂量半身照射,低剂量半身照射方法为10 cGy/次,2次/周,总剂量为100 cGy,每次均间隔6~8 h再行常规放疗;RR组10例患者只予以常规放疗。采用流式细胞术(FCM)双标法检测HBR与RR组在放疗前、中、后外周血淋巴细胞CD4、CD8、CD25和CD56等指标的变化。结果 照射后RR组患者的CD4+ CD8+降低(P<0.05),HBR组患者的CD4+升高(P<0.05),CD25+和CD56+分子表达均明显地增加(P<0.05),放疗前和放疗后CD8+均低(P<0.05),放疗中(P<0.05)和放疗后(P<0.01)CD4+ CD8+均高。结论 低剂量半身照射可增强机体的免疫功能。  相似文献   
956.
In recent years, owing to the contributions of a few research groups, some new gold(III) compounds – either simple coordination complexes or organogold compounds – have been prepared that are sufficiently stable under physiological conditions and are promising candidates for pharmacological testing as cytotoxic and antitumor agents. In vitro pharmacological studies point out that some of these novel gold(III) complexes are highly cytotoxic toward cultured human tumor cell lines and are able to overcome resistance to platinum. Significant differences in the spectrum of action were observed compared with cisplatin. Studies are in progress to elucidate the mechanism of action of these compounds. The cellular effects of two representative gold(III) complexes are described. Preliminary results on binding to DNA in vitro are presented, pointing out that the interactions are generally weak. The implications of these results for the development of gold(III) complexes as a new family of cytotoxic and antitumor agents are discussed.  相似文献   
957.
In this review, the authors discuss the role of ECG in prediction of stroke. ECG plays an important role in detection of several stroke risk factors/predictors including atrial fibrillation and left ventricular hypertrophy; both are components of the Framingham Stroke Risk Score. Multiple other ECG traits have also emerged as potential predictors of stroke, namely cardiac electrical/structural remodeling – Q wave, QRS/QT duration, bundle blocks, P wave duration/amplitude/dispersion, other waveform angles and slopes; higher automaticity – ectopic beats; and re-entry – atrial tachyarrhythmia; and higher vulnerability to arrhythmia – heart rate and its variability. Most of these predictors are not ready for prime time yet; however, further research focusing on their role in risk stratification and prevention of stroke may be useful. In this article, the authors discuss the prevalence, mechanisms and clinical applications of traditional and novel ECG markers in the prevention and treatment of stroke.  相似文献   
958.
Copper microparticles have been dispersed in anion-exchange polymer films coated on carbon electrodes by oxidative electropolymerization of pyrrole–alkylammonium monomers. Incorporation of copper in polymeric films was effected by impregnation of copper-oxalate anionic complexes followed by an electroreductive precipitation to copper metal, or by electroreduction of polymer coated electrodes immersed in copper–oxalate aqueous solutions. The deposition process was examined by voltammetry. Scanning electron microscopy showed a dispersion of metal particles from 50–100 up to 300 nm, according to the lipophilic character of the polymer, located in a layer near the carbon  polymer interface. A study of the electrocatalytic activity in the reduction of nitrobenzene to aniline at these materials was performed. The cathodes appeared much more active than bulk copper electrodes.  相似文献   
959.
We studied the effects of intensive plasma exchange on endocrine ophthalmopathy in 12 patients with Graves' disease and one with Hashimoto's thyroiditis. All patients were euthyroid at the time of plasma exchange. All but five had concomitant treatment with azathioprine. Each patient had a treatment period consisting of six plasma exchanges performed in 2-3 weeks; two patients were treated in two periods. Each time a mean of 2.4 liters plasma was exchanged. There was a prompt reduction in the concentration of circulating immune complexes and/or thyrotropin receptor antibodies following plasma exchange. Six of the 13 patients improved their proptosis; their median duration of eye symptoms before treatment was less than 8 months. In patients suffering from eye symptoms for more than 1 year improvement was rare. Overall the Hertel values were 24.1 +/- 4.4 (SD) before and 22.8 +/- 3.4 after plasma exchange for the left eyes (P = 0.07) and 23.8 +/- 4.0 before and 23.0 +/- 3.8 after for the right eyes (P = 0.09). Nine patients altogether improved their ophthalmopathy index and periorbital oedema. In patients with disabling endocrine ophthalmopathy plasma exchange may sometimes be of value to induce a relief of the ophthalmopathy; when it is used it should be instituted before fibrotic changes occur. We suggest that concomitant immunosuppressive drugs should be given to prevent rebound phenomenon induced by plasma exchange. To establish the role of plasma exchange in the treatment of endocrine ophthalmopathy controlled studies should be performed.  相似文献   
960.
A case of immunological adverse reaction to the commonly used bladder irrigation fluid, glycine, is reported, with discussion of the immunological investigations and possible significance of the results.  相似文献   
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