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   75篇
  免费   8篇
  83篇
  2016年   3篇
  2014年   8篇
  2013年   3篇
  2012年   5篇
  2011年   4篇
  2010年   4篇
  2009年   3篇
  2008年   3篇
  2007年   3篇
  2006年   1篇
  2004年   5篇
  2003年   4篇
  2002年   5篇
  2001年   1篇
  2000年   4篇
  1999年   4篇
  1998年   1篇
  1996年   1篇
  1994年   1篇
  1993年   5篇
  1992年   3篇
  1991年   2篇
  1990年   4篇
  1989年   1篇
  1988年   2篇
  1987年   1篇
  1983年   1篇
  1970年   1篇
排序方式: 共有83条查询结果,搜索用时 0 毫秒
71.
Cyclins are indispensable elements of the cell cycle and derangement of their function can lead to cancer formation. Recent studies have also revealed more mechanisms through which cyclins can express their oncogenic potential. This review focuses on the aberrant expression of G1/S cyclins and especially cyclin D and cyclin E; the pathways through which they lead to tumour formation and their involvement in different types of cancer. These elements indicate the mechanisms that could act as targets for cancer therapy.  相似文献   
72.
Objective: Increased fat infiltration in skeletal muscle has been associated with diabetes. Quantitative computed tomography (QCT) can be used to measure muscle density, which reflects the lipid content of skeletal muscle such that greater fat infiltration in skeletal muscle is associated with lower muscle density. The relative contribution of genetic and environmental factors to fat infiltration in skeletal muscle has not been assessed. Therefore, our aim is to determine genetic and environmental contributions to measures of skeletal muscle composition, and describe their associations with type 2 diabetes in multigenerational families of African ancestry. Methods and Procedures: Peripheral QCT (pQCT) measures of skeletal muscle density were obtained for the calf in 471 individuals (60% women; mean 43 years) belonging to eight large, multigenerational Afro‐Caribbean families (mean family size 51 individuals; 3,535 relative pairs). Results: The proportion of variance in muscle density due to additive genetic effects (residual heritability) was 35.0% (P < 0.001) and significant covariates (age, gender, BMI, and parity) explained 55.0% of the total phenotypic variation in muscle density. Muscle density was lower (P < 0.001) in 62 diabetics (69.5 mg/cm3) than in 339 nondiabetics (74.3 mg/cm3) and remained significant after adjusting for age, gender, and BMI (P = 0.005) or age, gender, and waist circumference (P = 0.01). Discussion: Our results provide new evidence that ectopic lipid deposition in skeletal muscle is a heritable trait and is associated with diabetes, independent of overall and central obesity in families of African heritage. Genome‐wide screens and candidate gene studies are warranted to identify the genetic factors contributing to ectopic deposition of skeletal muscle fat.  相似文献   
73.
74.
75.
Natural blood-borne antigen-presenting cells (APCs) were tested for their ability to augment antigen presentation for SIV vaccines. Fibrocytes and monocyte-derived dendritic cells (DCs) were isolated from multiple Macaca fascicularis . Macaque fibrocytes displayed the characteristic cellular morphology and stained positive for CD34 and collagen, as observed in human and murine fibrocytes. Macaque DCs were generated from monocytes by culturing in granulocyte–macrophage colony stimulating factor and interleukin-4 (IL-4). Two days after maturation, cells were enriched for the DC marker CD83. Fibrocytes and DCs were each transfected with green fluorescence protein expression plasmids or DNA expression vectors encoding all of the SIVmne structural and regulatory genes. Autologous DCs were re-infused into macaques subcutaneously (sc) following transfection; mixing with recombinant SIV antigens or inactivated whole SIV in vitro ; or mock-treatment. Autologous monocyte-derived DCs pulsed with whole inactivated SIV were re-infused and elicited cellular and/or humoral responses in vivo in eight of ten vaccinated macaques.  相似文献   
76.
Three SIVMne-infected female pigtailed macaques (Macaca nemestrina) were mated with two SIV-negative males. The females exhibited signs of SAIDS and SIVMne was readily isolated from peripheral blood mononuclear cells (PBMC). Both males became infected with SIVMne, developed SAIDS, and died. This is the first documented case of the transmission of SIVMne between adult macaques housed together. Although transmission through scratching or biting cannot be ruled out, heterosexual transmission appears the most likely mode of SIVMne transmission in this study.  相似文献   
77.
A primate lymphotropic lentivirus was isolated on Hut 78 cells after cocultivation of a lymph node from a macaque that died with malignant lymphoma. In earlier studies SIV/Mne was inoculated into 17 macaques and two baboons. All of the macaques became viremic and seropositive. Fifteen of the macaques succumbed to a classic AIDS-like disease, whereas the baboons did not become viremic. The SIV/Mne virus has now been molecularly cloned and inoculated into Macaca nemestrina and baboons. A new transmission study has been initiated to test the effects of route and dosage on disease.  相似文献   
78.
Z. Kuller  A. Gasith 《Hydrobiologia》1996,335(2):147-157
Rain-pool habitats are gradually disappearing in Israel as a result of agricultural and urban development. Present and past records of notostracan distribution here reveal a difference in the occurrence of Triops cancriformis and Lepidurus apus lubbocki, the former rather rare, and support the suggestion that species of Triops are more thermophilic than Lepidurus, with optimal hatching temperature 8–12°C higher. The limited distribution of T. cancriformis in Israel may be partly attributed to sub-optimal temperatures (<20°C) in early winter.All populations of T. cancriformis in Israel were monosexual female. Resting Notostraca eggs float and become exposed to light, needed for hatching, and to warm day-time temperatures at the water surface which enhance embryonic development. Exposure to higher temperatures may be particularly important for the thermophilic T. cancriformis in Israel, where deep water temperatures in early winter are often below hatching values.  相似文献   
79.
Campylobacter jejuni was selectively cultured in 33 (66%) of 50 Macaca fascicularis that had been imported from Indonesia. As there was no published information on the incidence of Campylobacter infection in nonhuman primates from Indonesia, a survey was conducted to determine the presence and incidence of Campylobacter jejuni in 50 macaques before they were exported from Indonesia. The organism was positively identified in 18 (36%) of the specimens examined. Repeat cultures after importation and during the quarantine period produced 37 of 48 (77%) positive results. Stool cultures from 57 other Macaca fascicularis and Macaca nemestrina in more preliminary stages of captivity in Indonesia produced only two positive identifications. These findings suggest that Campylobacter jejuni is not a natural pathogen of macaques in Indonesia, but it infects them after capture.  相似文献   
80.
Ion transport and ion selectivity in bean hypocotyl slices were investigated. The transport mechanism is practically independent of temperature and in short term experiments appears to be non-metabolic. Selectivity may be attributed either to specific adsorption sites or to the properties of the diffusion barrier. The fact that with a physical transport mechanism selectivity is observed only under physiological temperature conditions hints that a flexible barrier (plasmalemma?) rather than fixed adsorption sites should be regarded as governing the process.  相似文献   
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