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41.
Interleukin (IL)-17 is a proinflammatory cytokine primarily secreted by Th17 cells, which are a CD4+ T-cell subset. Th17 cells and IL-17 are important in the pathogenesis of multiple sclerosis and in its established animal model, experimental autoimmune encephalomyelitis (EAE). However, it is unclear whether IL-17 contributes to EAE immune tolerance. We used the myelin basic protein (MBP) peptide MBP 68–86 to induce nasal tolerance to EAE, and simultaneously interfered with the tolerance by treatment with different doses of IL-17. We found that IL-17 dramatically interfered with MBP 68–86-induced immune tolerance. IL-17 administration increased IL-6 release, skewing T cell differentiation towards Th17 cells and decreasing the number of Treg cells. This led to an imbalance between Treg cells and Th17 cells and spurred the development of EAE.  相似文献   
42.
The bcl-2 proto-oncogene, which inhibits programmed cell death (apoptosis), has recently been found to be cyclically expressed in human endometrium. In order to investigate its role in endometrial hyperlasia and neoplasia, bcl-2 expression was studied in 25 cases of endometrial carcinoma and 20 cases of endometrial hyperplasia (eight simple, two complex, and ten atypical hyperplasias). Uniform intense cytoplasmic bcl-2 expression was found in all cases of non-atypical hyperplasia, and less strong positivity in eight out of ten cases of atypical hyperplasia. In well-differentiated carcinomas, nine out of ten showed weak to moderate bcl-2 expression, whereas six out of seven poorly differentiated carcinomas were bcl-2-negative. Moderately differentiated tumours were an intermediate group, with six out of eight being positive. Widespread localization of bcl-2 protein to the chromosomes of dividing cells was also demonstrated, regardless of cytoplasmic bcl-2 expression, with rare staining of interphase nuclei. Our findings suggest a role for bcl-2 in the natural history of endometrial neoplasia and studies are needed to determine its usefulness as a prognostic marker. The finding of bcl-2 localization to chromosomes has important implications for its mode and site of action.  相似文献   
43.
The progressive myoclonus epilepsy of the Lafora type (LD; MIM 254780) is a rare autosomal recessive disorder characterized by epilepsy, myoclonus, progressive neurological deterioration, and the presence of periodic acid-Schiff-positive polyglucosan inclusions (Lafora bodies). Mutations in the EPM2A gene have recently been found to cause LD and about 30 or more mutations have been reported thus far. LD is relatively common in countries of the Mediterranean Basin, the Middle East, India, and Pakistan. Although a few sporadic cases with the typical LD phenotype have also been reported in the Far East including Korea and Japan, a recent effort to find mutations in Japanese LD families was not successful. In the present study, we report two novel mutations in a Korean girl with LD; a 1-bp insertion mutation (c.223insC; G75fsX107) in exon 1 and a missense mutation (c.559A>G; T187A) in exon 3 of the EPM2A gene. To our knowledge, this is the first report of a genetically confirmed case of LD in Koreans and also in the Far East.  相似文献   
44.
To determine structural features necessary for the production of direct mutagenic activity from oligoamine-nitrate reaction mixtures, we systematically tested a group of aliphatic amine substrates for comutagenic action with nitrite. The ability to react with nitrite and form direct-acting mutagenic derivatives was common to a reasonably well defined class of aliphatic polyamines. In general, primary-secondary diamino compounds were mutagenic in the Ames Salmonella tester system when reacted with nitrite, whereas primary and secondary amines produced no direct mutagenic activity when tested separately. In combination with teritary amino groups, primary amines were inactive; one secondary-tertiary amine was tested, and this substrate produced mutagenic activity.  相似文献   
45.
Metabolic syndrome is a worldwide health problem, and obesity is closely related to type 2 diabetes, cardiovascular disease, hypertension, and cancer. According to WHO in 2018, the prevalence of obesity in 2016 tripled compared to 1975. D. morbifera reduces bad cholesterol and triglycerides levels in the blood and provides various antioxidant nutrients and germicidal sub-stances, as well as selenium, which helps to remove active oxygen. Moreover, D. morbifera is useful for treating cardiovascular diseases, hypertension, hyperlipidemia, and diabetes. Therefore, we study in vivo efficacy of D. morbifera to investigate the prevention effect of obesity and cholesterol. The weight and body fat were effectively reduced by D. morbifera water (DLW) extract administration to high-fat diet-fed C57BL/6 mice compared to those of control mice. The group treated with DLW 500 mg∙kg−1∙d−1 had significantly lower body weights compared to the control group. In addition, High-density lipoprotein (HDL) cholesterol increased in the group treated with DLW 500 mg∙kg−1∙d−1. The effect of DLW on the serum lipid profile could be helpful to prevent obesity. DLW suppresses lipid formation in adipocytes and decreases body fat. In conclusion, DLW can be applied to develop anti-obesity functional foods and other products to reduce body fat.  相似文献   
46.
分别采用化学、声化学及光辐射等方法合成了1-丙二烯基-2,3,4,6四-氧-乙酰基-β-D-吡喃糖苷,结果表明声化学方法最有效、快速;借助电子自旋共振(ESR)技术及相关实验,证实此类糖苷的生成为一离子消除反应,所合成的糖苷化合物脱去乙酰基后对T、B淋巴细胞具有体外免疫调节作用。  相似文献   
47.
采用外耳道及鼓室再造术治疗先天性外耳道完全闭锁29例。统计各种外、中耳畸形情况,比较耳廓发育程度、颞骨相当于外耳道口处有无骨性小凹、术前听力损失程度与中耳畸形的关系,将术前的常规横断位CT检查结果与术中所见进行对照。结果显示,术前可通过耳廓发育程度、相当于外耳道口处有无骨性小凹、听力损失程度和颞骨CT扫描来综合估计中耳畸形情况,为术前了解手术难度和确定手术进路及方式提供一定的参考依据。  相似文献   
48.
49.
Annals of Surgical Oncology - Management of axillary lymph nodes in breast cancer has undergone significant change over the past decade through landmark clinical trials. This study aimed to assess...  相似文献   
50.
PurposeTo investigate the clinical characteristics, chemosensitivity, and outcome of metastatic upper tract urothelial carcinoma (UTUC).Patients and MethodsRecords of patients with metastatic UTUC since January 2005 were retrieved from a database that included clinical and survival data. Statistical analyses including survival and multivariate analyses of factors were respectively performed by the Kaplan-Meier method and Cox proportional hazard model.ResultsA total of 250 consecutive UTUC cases were evaluated. There were 56 patients (22.4%) with initially diagnosed stage IV disease. The most common metastatic sites were lung (39.6%), distant lymph nodes (39.2%), bone (19.6%), liver (18.0%), and adrenal gland (7.2%), respectively, and the local recurrence rate was 10.4%. Two hundred thirteen patients received first-line chemotherapy. The overall response rate was only 28.7% and the median progression-free survival time was only 5.0 months. The overall survival time of the cohort was 18.0 months. Multivariate analyses showed that initially diagnosed stage IV disease, number of metastatic organs ≥3, no response to chemotherapy and cycles of chemotherapy ≤2 were adverse prognosticators for overall survival.ConclusionUTUC presented to be more prone to metastasize than locally recur and thought to have low chemosensitivity. Stage IV disease at initial diagnosis, number of metastatic organs, response and cycles of chemotherapy were independent prognosticators for metastatic UTUC.  相似文献   
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