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61.
One new withanolide, (17S,20S,22R)-14alpha,15alpha,17beta,20beta-tetrahydroxy-1-oxowitha-2,5,24-trienolide) named coagulanolide (4) along with four known withanolides 1-3 and 5 have been isolated from Withania coagulans fruits and their structures were elucidated by spectroscopic techniques. The compounds 1-5 showed significant inhibition on postprandial rise in hyperglycemia post-sucrose load in normoglycemic rats as well as streptozotocin-induced diabetic rats. The compound 5 also showed significant fall on fasting blood glucose profile and improved the glucose tolerance of db/db mice. Further compound 5 showed antidyslipidemic activity in db/db mice. The median effective dose of the compound 5 was determined to be around 25 mg/kg in streptozotocin-induced diabetic rats, which is comparable to the standard antidiabetic drug metformin. Our results provide further support to explain the traditional use of W. coagulans as antihyperglycemic cum antidyslipidemic agent by the traditional medical practitioners.  相似文献   
62.
The American College of Medical Genetics and Genomics (ACMG) recommends that clinical sequencing laboratories return secondary findings in 56 genes associated with medically actionable conditions. Our goal was to apply a systematic, stringent approach consistent with clinical standards to estimate the prevalence of pathogenic variants associated with such conditions using a diverse sequencing reference sample. Candidate variants in the 56 ACMG genes were selected from Phase 1 of the 1000 Genomes dataset, which contains sequencing information on 1,092 unrelated individuals from across the world. These variants were filtered using the Human Gene Mutation Database (HGMD) Professional version and defined parameters, appraised through literature review, and examined by a clinical laboratory specialist and expert physician. Over 70,000 genetic variants were extracted from the 56 genes, and filtering identified 237 variants annotated as disease causing by HGMD Professional. Literature review and expert evaluation determined that 7 of these variants were pathogenic or likely pathogenic. Furthermore, 5 additional truncating variants not listed as disease causing in HGMD Professional were identified as likely pathogenic. These 12 secondary findings are associated with diseases that could inform medical follow-up, including cancer predisposition syndromes, cardiac conditions, and familial hypercholesterolemia. The majority of the identified medically actionable findings were in individuals from the European (5/379) and Americas (4/181) ancestry groups, with fewer findings in Asian (2/286) and African (1/246) ancestry groups. Our results suggest that medically relevant secondary findings can be identified in approximately 1% (12/1092) of individuals in a diverse reference sample. As clinical sequencing laboratories continue to implement the ACMG recommendations, our results highlight that at least a small number of potentially important secondary findings can be selected for return. Our results also confirm that understudied populations will not reap proportionate benefits of genomic medicine, highlighting the need for continued research efforts on genetic diseases in these populations.  相似文献   
63.
Upper Aero digestive Tract (UADT) is the commonest site for the development of second cancer in females after primary cervical cancer. Glutathione S-transferase (GSTM1 and / or T1) null genotype modulates the risk of developing UADT cancer (primary as well as second cancer). The aim of this study was to evaluate the difference in GST null genotype frequencies in females with paired cancers in the UADT and genital region as compared to females with paired cancers in the UADT and non-genital region. Forty-nine females with a cancer in the UADT and another cancer (at all sites-genital and non-genital) were identified from a database of patients with multiple primary neoplasms and were analyzed for the GSTM1 and T1 genotype in addition to known factors such as age, tobacco habits, alcohol habits and family history of cancer. Frequencies of GSTM1 null, GSTT1 null, and either GSTM1/T1 null were higher in females with paired occurrence of cancer in the UADT and genital site (54%, 33% and 75% respectively) in comparison to females with paired occurrence of cancer in the UADT and non-genital sites (22%, 6% and 24% respectively). The significantly higher inherited frequency of either GSTM1/T1 null genotype in females with a paired occurrence of cancers in UADT and genital region (p = 0.01), suggests that these females are more susceptible to damage by carcinogens as compared to females who have UADT cancers in association with cancers at non-genital sites.  相似文献   
64.
The introduction of culture-independent molecular screening techniques, especially based on 16S rRNA gene sequences, has allowed microbiologists to examine a facet of microbial diversity not necessarily reflected by the results of culturing studies. The bacterial community structure was studied for a pesticide-contaminated site that was subsequently remediated using an efficient degradative strain Arthrobacter protophormiae RKJ100. The efficiency of the bioremediation process was assessed by monitoring the depletion of the pollutant, and the effect of addition of an exogenous strain on the existing soil community structure was determined using molecular techniques. The 16S rRNA gene pool amplified from the soil metagenome was cloned and restriction fragment length polymorphism studies revealed 46 different phylotypes on the basis of similar banding patterns. Sequencing of representative clones of each phylotype showed that the community structure of the pesticide-contaminated soil was mainly constituted by Proteobacteria and Actinomycetes. Terminal restriction fragment length polymorphism analysis showed only nonsignificant changes in community structure during the process of bioremediation. Immobilized cells of strain RKJ100 enhanced pollutant degradation but seemed to have no detectable effects on the existing bacterial community structure.  相似文献   
65.
Molecular regulation of vessel maturation   总被引:44,自引:0,他引:44  
Jain RK 《Nature medicine》2003,9(6):685-693
The maturation of nascent vasculature, formed by vasculogenesis or angiogenesis, requires recruitment of mural cells, generation of an extracellular matrix and specialization of the vessel wall for structural support and regulation of vessel function. In addition, the vascular network must be organized so that all the parenchymal cells receive adequate nutrients. All of these processes are orchestrated by physical forces as well as by a constellation of ligands and receptors whose spatio-temporal patterns of expression and concentration are tightly regulated. Inappropriate levels of these physical forces or molecules produce an abnormal vasculature--a hallmark of various pathologies. Normalization of the abnormal vasculature can facilitate drug delivery to tumors and formation of a mature vasculature can help realize the promise of therapeutic angiogenesis and tissue engineering.  相似文献   
66.
Li F  Mandal M  Mishra SK  Barnes CJ  Kumar R 《FEBS letters》2002,524(1-3):49-53
To identify genes whose expression is modulated by heregulin-beta1 (HRG), a regulatory polypeptide for mammary epithelial cells, we performed differential display screening of MCF-7 cell mRNA. One cDNA clone upregulated by HRG was identical to human ADP-ribosylation factor 3 (ARF3), a guanine nucleotide-binding protein functioning in vesicular trafficking, phospholipase D activation and intracellular transport. HRG treatment increased expression of ARF3 mRNA and protein. Also, HRG triggered a rapid redistribution of ARF3, first to cell membranes and then to the nuclear compartment, where ARF3 colocalized with acetylated histone H3 in discrete regions. In addition, the ARF3 protein was developmentally regulated in the mammary gland with the highest levels in virgin and post-weaning glands. Together, these findings suggest for the first time that stimulation of ARF3 expression, subcellular redistribution and interaction with acetylated histone H3 may play a role in the action of HRG in mammary epithelial cells.  相似文献   
67.
68.
Allium sativum leaf agglutinin (ASAL) binds to several proteins in the midgut of Helicoverpa armigera and causes toxicity. Most of these were glycosylated. Six ASAL-binding proteins were selected for identification. PMF and MS/MS data showed their similarity with midgut aminopeptidase APN2, polycalins and alkaline phosphatase of H. armigera, cadherin-N protein (partial AGAP009726-PA) of Acyrthosiphon pisum, cytochrome P450 (CYP315A1) of Manduca sexta and alkaline phosphatase of Heliothis virescens. Some of the ASAL-binding midgut proteins were similar to the larval receptors responsible for the binding of δ-endotoxin proteins of Bacillus thuringiensis. Galanthus nivalis agglutinin also interacted with most of the ASAL-binding proteins. The ASAL showed resistance to midgut proteases and was detected in the larval hemolymph and excreta. Immunohistochemical staining revealed the presence of ASAL in the body tissue also.  相似文献   
69.
70.
Simple and cost-effective tools that identify patients at increased risk for adverse cardiovascular events are actively sought. High resting sinus heart rate and first degree AV block are easily recognized and commonly encountered findings in a cardiology practice. A growing body of epidemiological and clinical evidence has been shown them to be independent predictors of all-cause and cardiovascular mortality, both in the general population and in patients with structural heart disease. This paper reviews the important role of heart rate and first degree AV block in predicting cardiovascular outcomes, examines the pathophysiological mechanisms underlying this increased risk, and discusses the effectiveness of available therapies to favorably modify these risk factors.  相似文献   
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