首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   35篇
  免费   2篇
  2022年   3篇
  2021年   2篇
  2020年   2篇
  2019年   2篇
  2018年   3篇
  2017年   1篇
  2015年   5篇
  2014年   1篇
  2013年   3篇
  2012年   4篇
  2011年   1篇
  2007年   2篇
  2003年   3篇
  2002年   1篇
  1994年   1篇
  1992年   1篇
  1991年   1篇
  1988年   1篇
排序方式: 共有37条查询结果,搜索用时 109 毫秒
1.
A study of the diagnosis of hepatic and pancreatic malignancies by fine needle aspiration (FNA) was made, based on 221 aspirates obtained from 209 patients with histologic or clinical confirmation: 159 with hepatic and 50 with pancreatic lesions. The values of sensitivity, specificity and predictivity for positive FNA results were, respectively, 0.84, 0.96 and 1.0 for the liver and 0.76, 1.0 and 1.0 for the pancreas. The composition of the case material showed an incidence of malignant tumors of the liver and pancreas of 84% and 60%, respectively (among which the primary malignancies were 39% and 48%), while nonneoplastic lesions had incidences of 14% and 40%. However, conclusive FNA diagnoses of the histologic type of the primary and the site of origin of metastatic tumors were made in 60% of the hepatic lesions but in only 9% of the pancreatic lesions. Primary hepatocellular carcinoma was diagnosed by FNA of the liver in 95% of the cases; FNA specifically diagnosed 42% of intrahepatic bile duct carcinomas and 40% of hepatic metastases. These findings correlate with the unique cytologic features of primary hepatocellular carcinoma of intrahepatic rather nonspecific morphology of carcinoma of intrahepatic and extrahepatic origin, as well as of pancreatic ductal origin.  相似文献   
2.
3.
Incubation of rat liver mitochondria with 100-500 mM tyramine, a substrate for monoamine oxidases A and B (MAOs), in the presence of 30 mM Ca2+ induces matrix swelling, accompanied by collapse of membrane potential, efflux of endogenous Mg2+ and accumulated Ca2+ and oxidation of endogenous pyridine nucleotides. These effects are completely abolished in the presence of cyclosporin A, ADP, dithioerythritol and N-ethylmaleimide, thus confirming the induction of the mitochondrial membrane permeability transition (MPT). The observed partial protective effect exerted by catalase indicates the involvement of both MAO-derived hydrogen peroxide and aldehyde. Higher concentrations of tyramine (1-2 mM) are less effective or even completely ineffective. At these high concentrations tyramine has an inhibitory effect when the MPT is induced by 100 mM Ca2+. The MAO inhibitors clorgyline (50 mM) and pargyline (500 mM) completely protect against MPT induction by 100 mM tyramine but also inhibit the phenomenon, although with different efficacy, when it is induced by 100 mM Ca2+ in the absence of tyramine. Taken together, our data suggest that tyramine, clorgyline and pargyline act as modulators of the MPT either through a direct inducing/protective effect or by controlling hydrogen peroxide and aldehyde generation.  相似文献   
4.

Background

Everolimus is a mammalian target of rapamycin (mTOR) inhibitor approved for the treatment of metastatic renal cell carcinoma (mRCC). We aimed to assess the association between the baseline values and treatmentrelated modifications of total serum cholesterol (C), triglycerides (T), body mass index (BMI), fasting blood glucose level (FBG) and blood pressure (BP) levels and the outcome of patients treated with everolimus for mRCC.

Methods

177 patients were included in this retrospective analysis. Time to progression (TTP), clinical benefit (CB) and overall survival (OS) were evaluated.

Results

Basal BMI was significantly higher in patients who experienced a CB (p=0,0145). C,T and C+T raises were significantly associated with baseline BMI (p=0.0412, 0.0283 and 0.0001). Median TTP was significantly longer in patients with T raise compared to patients without T (10 vs 6, p=0.030), C (8 vs 5, p=0.042) and C+T raise (10.9 vs 5.0, p=0.003). At the multivariate analysis, only C+T increase was associated with improved TTP (p=0.005). T raise (21.0 vs 14.0, p=0.002) and C+T increase (21.0 vs 14.0, p=0.006) were correlated with improved OS but were not significant at multivariate analysis.

Conclusion

C+T raise is an early predictor for everolimus efficacy for patients with mRCC.  相似文献   
5.
6.
7.
Cedrela P. Browne is a genus of trees, strictly related to Toona, in the Meliaceae, a family of flowering plants in the order Sapindales, which is among the most diverse sources of secondary metabolites in the Angiospermae. The most abundant metabolites in these genera are limonoids, tetranortriterpenes possessing diverse structural features, apotirucallanes, tirucallanes, and other triterpenes. The chemical constituents isolated from the genera Cedrela and Toona over the past decades, together with their biological activities, have been compiled in this article. The allelochemical and the phytotoxic activity of limonoids and triterpenoids seem to play a crucial role in the ecological function of these metabolites. While, the most promising use in human field seems related to their antimalarial and anti-inflammatory effects, even that further investigation are still needed.  相似文献   
8.
Growth factors and mitogens use the Ras/Raf/MEK/ERK signaling cascade to transmit signals from their receptors to regulate gene expression and prevent apoptosis. Some components of these pathways are mutated or aberrantly expressed in human cancer (e.g., Ras, B-Raf). Mutations also occur at genes encoding upstream receptors (e.g., EGFR and Flt-3) and chimeric chromosomal translocations (e.g., BCR-ABL) which transmit their signals through these cascades. Even in the absence of obvious genetic mutations, this pathway has been reported to be activated in over 50% of acute myelogenous leukemia and acute lymphocytic leukemia and is also frequently activated in other cancer types (e.g., breast and prostate cancers). Importantly, this increased expression is associated with a poor prognosis. The Ras/Raf/MEK/ERK and Ras/PI3K/PTEN/Akt pathways interact with each other to regulate growth and in some cases tumorigenesis. For example, in some cells, PTEN mutation may contribute to suppression of the Raf/MEK/ERK cascade due to the ability of activated Akt to phosphorylate and inactivate different Rafs. Although both of these pathways are commonly thought to have anti-apoptotic and drug resistance effects on cells, they display different cell lineage specific effects. For example, Raf/MEK/ERK is usually associated with proliferation and drug resistance of hematopoietic cells, while activation of the Raf/MEK/ERK cascade is suppressed in some prostate cancer cell lines which have mutations at PTEN and express high levels of activated Akt. Furthermore the Ras/Raf/MEK/ERK and Ras/PI3K/PTEN/Akt pathways also interact with the p53 pathway. Some of these interactions can result in controlling the activity and subcellular localization of Bim, Bak, Bax, Puma and Noxa. Raf/MEK/ERK may promote cell cycle arrest in prostate cells and this may be regulated by p53 as restoration of wild-type p53 in p53 deficient prostate cancer cells results in their enhanced sensitivity to chemotherapeutic drugs and increased expression of Raf/MEK/ERK pathway. Thus in advanced prostate cancer, it may be advantageous to induce Raf/MEK/ERK expression to promote cell cycle arrest, while in hematopoietic cancers it may be beneficial to inhibit Raf/MEK/ERK induced proliferation and drug resistance. Thus the Raf/MEK/ERK pathway has different effects on growth, prevention of apoptosis, cell cycle arrest and induction of drug resistance in cells of various lineages which may be due to the presence of functional p53 and PTEN and the expression of lineage specific factors.  相似文献   
9.
Phytochemistry Reviews - Over the years, the attention towards the role of phytochemicals in dietary natural products in reducing the risk of developing cancer is rising. Cancer is the second...  相似文献   
10.
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号