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191.
Resource allocation patterns, as quantified by residual food intake (RFI), and the consequences for offspring development were investigated during lactation in 96 females of a mouse line selected for 104 generations for high litter size at birth (S-line) and in 87 females of a non-selected control line (C-line). Litters of 45 C-line dams (Cs) and 48 S-line dams (Ss) were standardised (s) at birth; other dams (ns) supported total number of pups born (Cns and Sns, respectively). RFI during lactation was significantly lower in Sns-dams than in C-line dams and Sns-dams. After weaning Sns-dams seemed to be able to restore the negative resource situation. Sns-pups were about 25% less mature than Cns-pups at all times. Maturity was similar for Cs- and Ss-pups from 2 d in lactation on, and about 18% and 53% higher than Cns- and Sns-pups. The pre-weaning mortality rate was significantly higher in Sns-litters (35.6 ± 2.76) than in Cns-litters (4.95 ± 2.23). The results suggest that S-line dams allocated considerably more resources to maintenance of offspring than C-line dams. This was insufficient to provide the offspring with an adequate amount of resources, resulting in reduced pup development and increased pre-weaning mortality rates.  相似文献   
192.
Consumption of an otherwise balanced ration containing 1% of corn invaded by Fusarium tricinctum isolate 2061-C resulted in the death of 13% of turkey poults within 35 days, in decreased feed efficiency and weight gain, and moderate development of bilateral necrotic lesions at angles of the mouth, especially in those that succumbed. Consumption of a ration with 2% of corn invaded by F. tricinctum resulted in death of 60 to 83% of the birds, in greatly reduced growth and feed efficiency in the survivors, and in development of severe mouth lesions. Consumption of rations containing 5, 10, and 20% of corn invaded by the fungus resulted in death of all birds in 5 to 15 days.  相似文献   
193.
Circulating tumor cells (CTCs) are the potential precursors of metastatic disease. Most assays established for the enumeration of CTCs so far–including the gold standard CellSearch—rely on the expression of the cell surface marker epithelial cell adhesion molecule (EpCAM). But, these approaches may not detect CTCs that express no/low levels of EpCAM, e.g. by undergoing epithelial-to-mesenchymal transition (EMT). Here we present an enrichment strategy combining different antibodies specific for surface proteins and extracellular matrix (ECM) components to capture an EpCAMlow/neg cell line and EpCAMneg CTCs from blood samples of breast cancer patients depleted for EpCAM-positive cells. The expression of respective proteins (Trop2, CD49f, c-Met, CK8, CD44, ADAM8, CD146, TEM8, CD47) was verified by immunofluorescence on EpCAMpos (e.g. MCF7, SKBR3) and EpCAMlow/neg (MDA-MB-231) breast cancer cell lines. To test antibodies and ECM proteins (e.g. hyaluronic acid (HA), collagen I, laminin) for capturing EpCAMneg cells, the capture molecules were first spotted in a single- and multi-array format onto aldehyde-coated glass slides. Tumor cell adhesion of EpCAMpos/neg cell lines was then determined and visualized by Coomassie/MitoTracker staining. In consequence, marginal binding of EpCAMlow/neg MDA-MB-231 cells to EpCAM-antibodies could be observed. However, efficient adhesion/capturing of EpCAMlow/neg cells could be achieved via HA and immobilized antibodies against CD49f and Trop2. Optimal capture conditions were then applied to immunomagnetic beads to detect EpCAMneg CTCs from clinical samples. Captured CTCs were verified/quantified by immunofluorescence staining for anti-pan-Cytokeratin (CK)-FITC/anti-CD45 AF647/DAPI. In total, in 20 out of 29 EpCAM-depleted fractions (69%) from 25 metastatic breast cancer patients additional EpCAMneg CTCs could be identified [range of 1–24 CTCs per sample] applying Trop2, CD49f, c-Met, CK8 and/or HA magnetic enrichment. EpCAMneg dual-positive (CKpos/CD45pos) cells could be traced in 28 out of 29 samples [range 1–480]. By single-cell array-based comparative genomic hybridization we were able to demonstrate the malignant nature of one EpCAMneg subpopulation. In conclusion, we established a novel enhanced CTC enrichment strategy to capture EpCAMneg CTCs from clinical blood samples by targeting various cell surface antigens with antibody mixtures and ECM components.  相似文献   
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CXCR4 and CXCR7 have distinct functions in regulating interneuron migration   总被引:1,自引:0,他引:1  
CXCL12/CXCR4 signaling is critical for cortical interneuron migration and their final laminar distribution. No information is yet available on CXCR7, a newly defined CXCL12 receptor. Here we demonstrated that CXCR7 regulated interneuron migration autonomously, as well as nonautonomously through its expression in immature projection neurons. Migrating cortical interneurons coexpressed Cxcr4 and Cxcr7, and Cxcr7(-/-) and Cxcr4(-/-) mutants had similar defects in interneuron positioning. Ectopic CXCL12 expression and pharmacological blockade of CXCR4 in Cxcr7(-/-) mutants showed that both receptors were essential for responding to CXCL12 during interneuron migration. Furthermore, live imaging revealed that Cxcr4(-/-) and Cxcr7(-/-) mutants had opposite defects in interneuron motility and leading process morphology. In?vivo inhibition of Gα(i/o) signaling in migrating interneurons phenocopied the interneuron lamination defects of Cxcr4(-/-) mutants. On the other hand, CXCL12 stimulation of CXCR7, but not CXCR4, promoted MAP kinase signaling. Thus, we suggest that CXCR4 and CXCR7 have distinct roles and signal transduction in regulating interneuron movement and laminar positioning.  相似文献   
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Genome-wide association studies (GWAS) in several populations have demonstrated significant association of the IL23R gene with IBD (Crohn's disease (CD) and ulcerative colitis (UC)) and psoriasis, suggesting that perturbation of the IL-23 signaling pathway is relevant to the pathophysiology of these diseases. One particular variant, R381Q (rs11209026), confers strong protection against development of CD. We investigated the effects of this variant in primary T cells from healthy donors carrying IL23R(R381) and IL23R(Q381) haplotypes. Using a proprietary anti-IL23R antibody, ELISA, flow cytometry, phosphoflow and real-time RT-PCR methods, we examined IL23R expression and STAT3 phosphorylation and activation in response to IL-23. IL23R(Q381) was associated with reduced STAT3 phosphorylation upon stimulation with IL-23 and decreased number of IL-23 responsive T-cells. We also observed slightly reduced levels of proinflammatory cytokine secretion in IL23R(Q381) positive donors. Our study shows conclusively that IL23R(Q381) is a loss-of-function allele, further strengthening the implication from GWAS results that the IL-23 pathway is pathogenic in human disease. This data provides an explanation for the protective role of R381Q in CD and may lead to the development of improved therapeutics for autoimmune disorders like CD.  相似文献   
200.

Background:

Limited evidence suggests that adiposity and lack of physical activity may increase the risk of chronic obstructive pulmonary disease (COPD). We investigated the relation of body size and physical activity with incidence of COPD.

Methods:

We obtained data on anthropometric measurements and physical activity from 113 279 participants in the National Institutes of Health–AARP Diet and Health Study who reported no diagnosis of COPD at baseline (1995–1996). We estimated associations between these measurements and subsequent diagnosis of COPD between 1996 and 2006, with extensive adjustment for smoking and other potentially confounding variables.

Results:

Participants reported 3648 new COPD diagnoses during follow-up. The incidence of COPD was higher in both severely obese (body mass index [BMI]D≥ 35) and underweight (BMID< 18.5) participants, but after adjustment for waist circumference, only underweight remained positively associated with COPD (relative risk [RR]D1.56, 95% confidence interval [CI]D1.15–2.11). Larger waist circumference (highest v. normal categories, adjusted RRD1.72, 95% CID1.37–2.16) and higher waist–hip ratio (highest v. normal categories, adjusted RRD1.46, 95% CID1.23–1.73) were also positively associated with COPD. In contrast, hip circumference (highest v. normal categories, adjusted RR 0.78, 95% CI 0.62–0.98) and physical activity (≥ 5 v. 0 times/wk, adjusted RRD0.71, 95% CID0.63–0.79) were inversely associated with COPD.

Interpretation:

Obesity, in particular abdominal adiposity, was associated with an increased risk of COPD, and increased hip circumference and physical activity were associated with a decreased risk of COPD. These findings suggest that following guidelines for a healthy body weight, body shape and physical activity decrease the risk of COPD.Chronic obstructive pulmonary disease (COPD) is a progressive, irreversible condition that severely affects quality of life1 and ability to work.2 Direct and indirect annual costs of COPD, including inpatient and outpatient care, medication and loss of productivity, sum to $50 billion in the United States3 and R39 billion (about US$50 billion) in Europe.4Chronic obstructive pulmonary disease may be prevented by avoidance of tobacco smoke, occupational dust and other environmental air pollution.5 Body mass index (BMI) and physical activity are established correlates of disease progression among patients with COPD,6,7 but data relating body size or physical activity to incident COPD are sparse. The few studies available are based on small samples and show inverse relations of both BMI8,9 and physical activity10,11 to incidence of COPD. Data are lacking regarding waist or hip circumference in relation to COPD incidence. We therefore examined BMI, waist circumference, hip circumference, waist–hip ratio and physical activity in relation to incidence of COPD in a large cohort of women and men in the US.  相似文献   
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