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51.
Pharmacological effects of green tea on the gastrointestinal system   总被引:11,自引:0,他引:11  
Green tea is rich in polyphenolic compounds, with catechins as its major component. Studies have shown that catechins possess diverse pharmacological properties that include anti-oxidative, anti-inflammatory, anti-carcinogenic, anti-arteriosclerotic and anti-bacterial effects. In the gastrointestinal tract, green tea was found to activate intracellular antioxidants, inhibit procarcinogen formation, suppress angiogenesis and cancer cell proliferation. Studies on the preventive effect of green tea in esophageal cancer have produced inconsistent results; however, inverse relationships of tea consumption with cancers of the stomach and colon have been widely reported. Green tea is effective to prevent dental caries and reduce cholesterols and lipids absorption in the gastrointestinal tract, thus benefits subjects with cardiovascular disorders. As tea catechins are well absorbed in the gastrointestinal tract and they interact synergistically in their disease-modifying actions, thus drinking unfractionated green tea is the most simple and beneficial way to prevent gastrointestinal disorders.  相似文献   
52.
Tumor necrosis factor (TNF) receptor 1-associated death domain protein (TRADD) is an adaptor protein known to be involved in the TNF signaling pathway as well as signaling of other members of the TNF receptor superfamily, including DR3, DR6, p75(NTR), and the Epstein-Barr virus latent membrane protein 1. Current knowledge of the function of the adaptor protein has been derived from studies examining its over-expression in either wild-type or mutated forms. In this study, we analyzed the consequences of antisense oligonucleotide (ASO)-mediated depletion of endogenous TRADD on TNF induction of inflammation-related gene products, such as intercellular adhesion molecule-1, and associated kinase signaling pathways in human umbilical vein endothelial cells. A broader perspective of TRADD's role in TNF signaling was indicated by microarray gene expression analysis, where 20 of 24 genes that showed a 5-fold or greater increase in TNF-induced mRNA expression levels displayed a reduction in TNF-induced expression as a consequence of ASO-mediated knockdown of TRADD. Reduced activation of the nuclear factor-kappaB and c-Jun NH(2)-terminal kinase pathways, as measured by IkappaB-alpha protein levels and the extent of c-Jun phosphorylation, was also observed. These results indicate usage of antisense inhibitors of TRADD expression for modulating diseases associated with TRADD-dependent signal transduction pathways.  相似文献   
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This work aims to fabricate a large-area ceramic substrate for the application of probe cards. Mullite (M) and cordierite (C), which both have a low thermal expansion coefficient, excellent resistance to thermal shock, and high durability, were selected as starting powders. The mullite–cordierite composites were produced through different composition ratios of starting powders (M:C = 100:0, M:C = 90:10, M:C = 70:30, M:C = 50:50, M:C = 30:70, and M:C = 0:100). The effects of composition ratio and sintering temperature on the density, porosity, thermal expansion coefficient, and flexural strength of the mullite–cordierite composite pellets were investigated. The results showed that the mullite–cordierite composite pellet containing 70 wt% mullite and 30 wt% cordierite sintered at 1350 °C performed exceptionally well. Based on these findings, a large-area mullite–cordierite composite substrate with a diameter of 320 mm for use in semiconductor probe cards was successfully fabricated. Additionally, the changes in sheet resistance and flexural strength were measured to determine the effect of the environmental tests on the large-area substrate such as damp heat and thermal shock. The results indicated that the mullite–cordierite composite substrate was extremely reliable and durable.  相似文献   
55.
Intralymphatic histiocytosis (ILH) is a rare cutaneous condition with uncertain pathogenesis. It is characterized by dilated lymphatic vessels that contain histiocytes within their lumina. Although the etiology of ILH remains unknown, it has been associated with various inflammatory and neoplastic diseases, such as rheumatoid arthritis (RA), reaction to metal joint implants and Merkel cell carcinoma, breast cancer and colon cancer. An 83-year-old female presented with an erythematous patch on the left forearm that had appeared six months previous. She had suffered from osteoarthritis (OA) and the cutaneous lesion was located in the vicinity of the affected joint. Skin biopsy from the lesion showed dilated dermal vessels and some ectatic vessels that contained many mononuclear histiocytes. Based on the clinical and histopathological findings, we diagnosed her with ILH with OA. Two sessions of intralesional triamcinolone acetonide injection (5 mg/ml) were administered to treat the skin lesion, which gradually improved over a period of a few months. We here report a rare case of ILH associated with degenerative OA.  相似文献   
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Background/AimsWe investigated the effect of metabolic dysfunction-associated fatty liver disease (MAFLD) on future mortality and cardiovascular disease (CVD) using a prospective community-based cohort study.MethodsIndividuals from two community-based cohorts who were 40 to 70 years old were prospectively followed for 16 years. MAFLD was defined as a high fatty liver index (FLI ≥60) plus one of the following conditions overweight/obesity (body mass index ≥23 kg/m2), type 2 diabetes mellitus, or ≥2 metabolic risk abnormalities. Nonalcoholic fatty liver disease (NAFLD) was defined as FLI ≥60 without any secondary cause of hepatic steatosis.ResultsAmong 8,919 subjects (age 52.2±8.9 years, 47.7% of males), 1,509 (16.9%) had MAFLD. During the median follow-up of 15.7 years, MAFLD independently predicted overall mortality after adjustment for confounders (hazard ratio [HR], 1.33; 95% confidence interval [CI], 1.05 to 1.69) but NAFLD did not (HR, 1.20; 95% CI, 0.94 to 1.53). MAFLD also predicted CVD after adjustment for age, sex, and body mass index (HR, 1.35; 95% CI, 1.13 to 1.62), which lost its statistical significance by further adjustments. Stratified analysis indicated that metabolic dysfunction contributed to mortality (HR, 1.51; 95% CI, 1.21 to 1.89) and CVD (HR, 1.27; 95% CI, 1.02 to 1.59). Among metabolic dysfunctions used for defining MAFLD, type 2 diabetes mellitus in MAFLD increased the risk of both mortality (HR, 2.07; 95% CI, 1.52 to 2.81) and CVD (HR, 1.42; 95% CI, 1.09 to 1.85).ConclusionsMAFLD independently increased overall mortality. Heterogeneity in mortality and CVD risk of subjects with MAFLD may be determined by the accompanying metabolic dysfunctions.  相似文献   
58.
目的探讨外周血来源的内皮前体细胞自体移植,对大鼠急性心肌梗死后微血管新生与心功能的影响。方法抽取SD大鼠外周动脉血,应用Ficoll密度梯度离心法获取单个核细胞。应用含有VEGF和bFGF的特定培养基体外培养,得到内皮前体细胞;结扎SD大鼠冠状动脉左前降支,建立急性心肌梗死模型;然后将得到的自体内皮前体细胞植入缺血心肌局部区域。对照组动物注入细胞培养液。结果与对照组比较,细胞移植组大鼠心功能明显改善,心肌收缩力显著优于对照组;梗死心肌微血管新生更为明显。结论急性心肌梗死心肌局部移植外周血来源的自体内皮前体细胞,能够促进血管新生;对局部梗死心肌组织结构有一定的保护作用,并可在不同时点不同程度恢复心肌收缩力,显著改善心功能。  相似文献   
59.
For the long‐term efficacy of dry eye disease treatment, relieving underlying inflammation is necessary. Imatinib mesylate is a novel ophthalmic formulation of imatinib mesylate, which is expected to alleviate inflammation by inhibiting the discoidin domain receptor 1 activity. This study aims to evaluate the safety and pharmacokinetics of imatinib mesylate in healthy subjects. A randomized, double‐blind, placebo‐controlled study was conducted. In a single ascending dose, 16 subjects received a single eye drop of imatinib mesylate 0.1%, 0.3%, or matching placebo. In the multiple ascending dose (MAD), subjects received multiple eye drops of imatinib mesylate 0.1%, 0.3%, or matching placebo once daily for 7 days. Safety and tolerability were assessed by ophthalmic examination, including the visual analog scale (VAS) to monitor the burning sensation in the eyes. A total of four treatment‐emergent adverse events (TEAEs) occurred during the study. All TEAEs were mildly severe with no serious cases. VAS results in the 0.1% MAD group exhibited highest score of two points, whereas it was less than one point in others. Insignificant difference between the imatinib mesylate and placebo groups in the VAS results was seen. After a single dose administration of imatinib mesylate 0.1%, all plasma concentrations were below the lower limit of quantification. The peak plasma concentrations of imatinib were less than 0.54 µg/L in all groups. In conclusion, a single and multiple topical ophthalmic administration of imatinib mesylate was well‐tolerated in healthy subjects. Because there was minimal systemic exposure to imatinib, the adverse effect in the body seems to be insignificant.  相似文献   
60.
Data collected among African‐American and Caucasian women and men in the southeastern USA indicate that participants' perceptions of nature, God's will and the human body influence reproductive health and decision‐making. Attitudes about the health care system, pharmaceutical companies and government programmes for fertility regulation reinforce these views and may negatively affect willingness to use contraceptive methods consistently and correctly.  相似文献   
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