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   137篇
  免费   14篇
  国内免费   9篇
  160篇
  2023年   1篇
  2022年   1篇
  2019年   1篇
  2018年   1篇
  2017年   1篇
  2016年   1篇
  2015年   14篇
  2014年   9篇
  2013年   8篇
  2012年   7篇
  2011年   13篇
  2010年   10篇
  2009年   7篇
  2008年   6篇
  2007年   5篇
  2006年   10篇
  2005年   3篇
  2004年   5篇
  2003年   2篇
  2002年   1篇
  2001年   4篇
  2000年   2篇
  1999年   3篇
  1998年   9篇
  1997年   9篇
  1996年   4篇
  1995年   1篇
  1994年   6篇
  1993年   1篇
  1992年   1篇
  1991年   1篇
  1988年   1篇
  1987年   1篇
  1986年   2篇
  1985年   1篇
  1982年   2篇
  1977年   2篇
  1974年   1篇
  1955年   1篇
  1954年   2篇
排序方式: 共有160条查询结果,搜索用时 15 毫秒
81.
82.
A new species of Gesneriaceae from Honghe County, Southeastern Yunnan, China, Tremacron hongheense WH. Chen & YM. Shui, is described and illustrated. The new species is similar to Tremacron forrestii Craib, but differs by its leaf blade adaxially sparsely long setose (vs. densely white appressed pubescent and sparsely rusty brown villous), corolla tube outside short white glandular (vs. nearly glabrous), corolla lobes red and thickening at apex, especially adaxial lip (vs. yellow and not thickening), stamens 16-18cm long (vs. 04-12cm long), staminode 05-14cm long (vs. 02-04cm long).  相似文献   
83.
84.
85.
Methotrexate has been a clinical agent used in cancer, immunosuppression, rheumatoid arthritis and other highly proliferative diseases for many years, yet its underlying molecular mechanism of action in these therapeutic areas is still unclear. We present a chemical proteomics approach that uses ultra-sensitive mass spectrometry coupled to an inverse protein-ligand docking computational technique to unravel the mechanism of action of this drug. Using methotrexate tethered to a solid support we were able to isolate a signficant number of proteins. We effectively captured a large portion of the de novo purine metaolome and propose a pathway architecture similar to that seen in signaling pathways and consistent with substrate channeling. More importantly, we were able to capture protein targets that could potentially provide new insights into the mechanism of action of methotrexate in rheumatoid arthritis and immunosuppression. The application of this approach to other drugs and drug candidates may facilitate the prediction of unknown and secondary therapeutic target proteins and those related to the side effects and toxicity. These results demonstrate that this proteomics technology could play an important role in drug discovery and development since it allows monitoring of the interactions between a drug and the protein content of a cell.  相似文献   
86.

Background

Cerebral ischaemia initiates an inflammatory response in the brain and periphery. We assessed the relationship between peak values of plasma interleukin-6 (IL-6) in the first week after ischaemic stroke, with measures of stroke severity and outcome.

Methods

Thirty-seven patients with ischaemic stroke were prospectively recruited. Plasma IL-6, and other markers of peripheral inflammation, were measured at pre-determined timepoints in the first week after stroke onset. Primary analyses were the association between peak plasma IL-6 concentration with both modified Rankin score (mRS) at 3 months and computed tomography (CT) brain infarct volume.

Results

Peak plasma IL-6 concentration correlated significantly (p < 0.001) with CT brain infarct volume (r = 0.75) and mRS at 3 months (r = 0.72). It correlated similarly with clinical outcome at 12 months or stroke severity. Strong associations were also noted between either peak plasma C-reactive protein (CRP) concentration or white blood cell (WBC) count, and all outcome measures.

Conclusions

These data provide evidence that the magnitude of the peripheral inflammatory response is related to the severity of acute ischaemic stroke, and clinical outcome.  相似文献   
87.
NSD3s, the proline-tryptophan-tryptophan-proline (PWWP) domain-containing, short isoform of the human oncoprotein NSD3, displays high transforming properties. Overexpression of human NSD3s or the yeast protein Pdp3 in Saccharomyces cerevisiae induces similar metabolic changes, including increased growth rate and sensitivity to oxidative stress, accompanied by decreased oxygen consumption. Here, we set out to elucidate the biochemical pathways leading to the observed metabolic phenotype by analyzing the alterations in yeast metabolome in response to NSD3s or Pdp3 overexpression using 1H nuclear magnetic resonance (NMR) metabolomics. We observed an increase in aspartate and alanine, together with a decrease in arginine levels, on overexpression of NSD3s or Pdp3, suggesting an increase in the rate of glutaminolysis. In addition, certain metabolites, including glutamate, valine, and phosphocholine were either NSD3s or Pdp3 specific, indicating that additional metabolic pathways are adapted in a protein-dependent manner. The observation that certain metabolic pathways are differentially regulated by NSD3s and Pdp3 suggests that, despite the structural similarity between their PWWP domains, the two proteins act by unique mechanisms and may recruit different downstream signaling complexes. This study establishes for the first time a functional link between the human oncoprotein NSD3s and cancer metabolic reprogramming.  相似文献   
88.
Thyroid hormone exhibits profound effects on neural progenitor turnover, survival, maturation, and differentiation during perinatal development. Studies over the past decade have revealed that thyroid hormone continues to retain an important influence on progenitors within the neurogenic niches of the adult mammalian brain. The focus of the current review is to critically examine and summarize the current state of understanding of the role of thyroid hormone in regulating adult neurogenesis within the major neurogenic niches of the subgranular zone in the hippocampus and the subventricular zone lining the lateral ventricles. We review in depth the studies that highlight a role for thyroid hormone, in particular the TRα1 receptor isoform, in regulating progenitor survival and commitment to a neuronal fate. We also discuss putative models for the mechanism of action of thyroid hormone/TRα1 on specific stages of subgranular zone and subventricular zone progenitor development, and highlight potential thyroid hormone responsive target genes that may contribute to the neurogenic effects of thyroid hormone. The effects of thyroid hormone on adult neurogenesis are discussed in the context of a potential role of these effects in the cognitive‐ and mood‐related consequences of thyroid hormone dysfunction. Finally, we detail hitherto unexplored aspects of the effects of thyroid hormone on adult neurogenesis that provide impetus for future studies to gain a deeper mechanistic insight into the neurogenic effects of thyroid hormone.

  相似文献   

89.
The Brazilian Amazon Region is a highly endemic area for hepatitis B virus (HBV). However, little is known regarding the genetic variability of the strains circulating in this geographical region. Here, we describe the first full-length genomes of HBV isolated in the Brazilian Amazon Region; these genomes are also the first complete HBV subgenotype D3 genomes reported for Brazil. The genomes of the five Brazilian isolates were all 3,182 base pairs in length and the isolates were classified as belonging to subgenotype D3, subtypes ayw2 (n = 3) and ayw3 (n = 2). Phylogenetic analysis suggested that the Brazilian sequences are not likely to be closely related to European D3 sequences. Such results will contribute to further epidemiological and evolutionary studies of HBV.  相似文献   
90.
There is little research investigating relationships between the Functional Movement Screen (FMS) and athletic performance in female athletes. This study analyzed the relationships between FMS (deep squat; hurdle step [HS]; in-line lunge [ILL]; shoulder mobility; active straight-leg raise [ASLR]; trunk stability push-up; rotary stability) scores, and performance tests (bilateral and unilateral sit-and-reach [flexibility]; 20-m sprint [linear speed]; 505 with turns from each leg; modified T-test with movement to left and right [change-of-direction speed]; bilateral and unilateral vertical and standing broad jumps; lateral jumps [leg power]). Nine healthy female recreational team sport athletes (age = 22.67 ± 5.12 years; height = 1.66 ± 0.05 m; body mass = 64.22 ± 4.44 kilograms) were screened in the FMS and completed the afore-mentioned tests. Percentage between-leg differences in unilateral sit-and-reach, 505 turns and the jumps, and difference between the T-test conditions, were also calculated. Spearman''s correlations (p ≤ 0.05) examined relationships between the FMS and performance tests. Stepwise multiple regressions (p ≤ 0.05) were conducted for the performance tests to determine FMS predictors. Unilateral sit-and-reach positive correlated with the left-leg ASLR (r = 0.704-0.725). However, higher-scoring HS, ILL, and ASLR related to poorer 505 and T-test performance (r = 0.722-0.829). A higher-scored left-leg ASLR related to a poorer unilateral vertical and standing broad jump, which were the only significant relationships for jump performance. Predictive data tended to confirm the correlations. The results suggest limitations in using the FMS to identify movement deficiencies that could negatively impact athletic performance in female team sport athletes.  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