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71.

Objective

To examine the association between nutrition knowledge, attitudes, and fruit/vegetable intake among Head Start teachers and their classroom mealtime behaviors (self-reported and observed).

Design

Cross-sectional design using observation and survey.

Setting

Sixteen Head Start centers across Rhode Island between September, 2014 and May, 2015.

Participants

Teachers were e-mailed about the study by directors and were recruited during on-site visits. A total of 85 participants enrolled through phone/e-mail (19%) or in person (81%).

Main Outcome Measures

Independent variables were nutrition knowledge, attitudes, and fruit/vegetable intake. The dependent variable was classroom mealtime behaviors (self-reported and observed).

Analysis

Regression analyses conducted on teacher mealtime behavior were examined separately for observation and self-report, with knowledge, attitudes, and fruit and vegetable intake as independent variables entered into the models, controlling for covariates.

Results

Nutrition attitudes were positively associated with teacher self-reported classroom mealtime behavior total score. Neither teacher nutrition knowledge nor fruit/vegetable intake was associated with observed or self-reported classroom mealtime behavior total scores.

Conclusion and Implications

There was limited support for associations among teacher knowledge, attitudes, and fruit/vegetable intake, and teacher classroom mealtime behavior. Findings showed that teacher mealtime behavior was significantly associated with teacher experience.  相似文献   
72.
Introduction This paper describes the care coordination training program and results of an evaluation from its pilot in seven states. Despite the importance of practice-based care coordination, only 42.3% of children with special health care needs (CYSHCN) met all needed components of care coordination as defined by the Maternal Child Health Bureau. Recognizing that children with medically complex conditions often have lower rates of achieving care coordination within a medical home, the Region 4 Midwest Genetics Collaborative worked with families to develop a training to empower families in care coordination. The Care Coordination: Empowering Families(CCEF) training provides families with the knowledge, tools, and resources to engage with health, education and family support systems. This article gives an overview of the training and comprehensive evaluation. Methods Participants were family caregivers of children with genetic conditions and other special health care needs recruited in one of seven pilot states. Evaluation data were collected from 190 participants prior to and immediately following the training. An additional follow-up assessment one full year post training was completed by 80 participants (a response rate of 42%). Results Families who attended the training report being the primary source of care coordination for their children and 83.7% see their role in their child’s healthcare changing as a result of the training. The findings suggest that peer support and communication with providers increased as a result of the training over the course of the study. The data suggest that the training impacted how the family interacts with the child’s doctor, including initiating conversations to prepare their child for transition to adult health care. Further, families report system-level improvements 1 year later compared to the pre-training assessment. Discussion CCEF training is a promising practice for facilitating medical home use among CYSHCN.  相似文献   
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The role of the central noradrenergic systems and corticotropin-releasing factor (CRF) in modulating defensive withdrawal behavior was studied in rats. The apparatus consisted of a small chamber set on one side of a one-meter open field, into which the rat was placed to start the test. When rats were unfamiliar with the apparatus, they displayed species typical defensive withdrawal behavior with long latencies to emerge from and a high proportion of time spent in the small chamber. Intraperitoneal administration of clonidine (0.03 mg/kg), l-propranolol (2.5 micrograms/kg), prazosin (0.1 mg/kg) or chlordiazepoxide (CDP, 5 mg/kg) each significantly decreased the latency to emerge from and the mean time spent in the small chamber (MTIC) and increased the number of chamber entries. When rats were familiar with the apparatus, prior restraint for 20 min significantly increased the latency and MTIC, and decreased the number of chamber entries and rears, but did not alter locomotor activity. Prazosin, clonidine, CDP, l-propranolol and the CRF-antagonist, alpha-helical CRF9-41 (25 micrograms i.c.v.), reversed the restraint-induced increase in the latency and MTIC. CRF (10-100 ng i.c.v.) dose-dependently induced defensive withdrawal behavior in rats familiar with the apparatus; the minimum statistically significant dose was 50 ng. dl-Propranolol (5 mg/kg) and CDP blocked the CRF-induced changes in the latency to emerge and the MTIC; whereas clonidine and prazosin significantly reduced the latency, but had no statistically significant effects on the MTIC. Phenylephrine (25-200 ng i.c.v.) dose-dependently induced defensive withdrawal behavior. This effect of phenylephrine (200 ng) was significantly antagonized by prazosin or alpha-helical CRF9-41 (25 or 50 mg i.c.v.), but not by CDP. Our results suggest that the hyperactivity of the central noradrenergic systems caused by exposure to the novel environment may stimulate the release of CRF, which through some unknown mechanism induces defensive withdrawal behavior in rats. Activation of beta adrenergic receptors may also induce defensive withdrawal.  相似文献   
75.
76.
A new metabolite of arachidonic acid, formed during interaction between thrombin- or collagen-stimulated platelets and unstimulated neutrophils, has been demonstrated by both thin-layer radiochromatography and high-performance liquid chromatography. Production of the 3H-labeled metabolite in combined suspensions containing [3H]arachidonate-labeled platelets and unlabeled neutrophils from aspirin-treated donors suggested that platelet 3H-labeled 12S-hydroxy-5,8-cis,10-trans,14-cis-icosatetraenoic acid (12-HETE) was the precursor. This was confirmed by identification of the same product when purified 12-[3H]HETE was added directly to unstimulated neutrophils. Hydrogenation and oxidation of the isolated product, followed by gas chromatography-mass spectrometry showed the structure to be 12S,20-dihydroxyicosatetraenoic acid. These experiments further show that platelet stimuli known to occur in vivo may initiate metabolic interactions between different cell types via the arachidonic acid pathway.  相似文献   
77.
Interleukin 4 (IL-4) is a potent mediator of growth and differentiation for various lymphoid and myeloid cells. To isolate a cDNA encoding the murine IL-4 receptor, we have developed an expression cloning method that uses biotinylated ligand as a probe and that may be generally applicable to cloning of receptor genes. COS-7 cells transiently transfected with the cloned full-length cDNA bind murine IL-4 specifically with a Kd = 165 pM. Crosslinking of 125I-labeled IL-4 to COS-7 cells transfected with the cDNA reveals binding to proteins of 120-140 kDa. IL-4-responsive cells also express IL-4-binding proteins of 120-140 kDa but show additional bands at 60-70 kDa; the relationship of the smaller proteins to the larger ones is unclear. The nucleotide sequence indicates that the full-length cDNA encodes 810 amino acids including the signal sequence. While no consensus sequence for protein kinases is present in the cytoplasmic domain, a sequence comparison with the erythropoietin receptor, the IL-6 receptor, and the beta chain of the IL-2 receptor reveals a significant homology in the extracellular domain, indicating that the IL-4 receptor is a member of a cytokine receptor family.  相似文献   
78.
Loss of chromosome 18q21 is well documented in colorectal cancer, and it has been suggested that this loss targets the DCC, DPC4/SMAD4, and SMAD2 genes. Recently, the importance of SMAD4, a downstream regulator in the TGF-beta signaling pathway, in colorectal cancer has been highlighted, although the frequency of SMAD4 mutations appears much lower than that of 18q21 loss. We set out to investigate allele loss, mutations, protein expression, and cytogenetics of chromosome 18 copy number in a collection of 44 colorectal cancer cell lines of known status with respect to microsatellite instability (MSI). Fourteen of thirty-two MSI(-) lines showed loss of SMAD4 protein expression; usually, one allele was lost and the other was mutated in one of a number of ways, including deletions of various sizes, splice site changes, and missense and nonsense point mutations (although no frameshifts). Of the 18 MSI(-) cancers with retained SMAD4 expression, four harbored missense mutations in the 3' part of the gene and showed allele loss. The remaining 14 MSI(-) lines had no detectable SMAD4 mutation, but all showed allele loss at SMAD4 and/or DCC. SMAD4 mutations can therefore account for about 50-60% of the 18q21 allele loss in colorectal cancer. No MSI(+) cancer showed loss of SMAD4 protein or SMAD4 mutation, and very few had allelic loss at SMAD4 or DCC, although many of these MSI(+) lines did carry TGFBIIR changes. Although SMAD4 mutations have been associated with late-stage or metastatic disease, our combined molecular and cytogenetic data best fit a model in which SMAD4 mutations occur before colorectal cancers become aneuploid/polyploid, but after the MSI(+) and MSI(-) pathways diverge. Thus, MSI(+) cancers may diverge first, followed by CIN(+) (chromosomal instability) cancers, leaving other cancers to follow a CIN(-)MSI(-) pathway.  相似文献   
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80.
Aim: We have generated a heterozygous glucokinase knockout mouse (gkdel/wt), upon which we investigated the effect of high‐fat diet (HFD) with respect to metabolic control and both hepatic and β‐cell gene expression. We also investigated the in vitro efficacy of a glucokinase activator (GKA) on glucose‐stimulated insulin secretion (GSIS) in gkdel/wtmouse islets. Methods: Male gkdel/wtand gkwt/wtmice were grouped (n = 8–10) at 10 weeks of age and fed HFD or chow diet (CD) for 10 weeks. Multiple parameters including blood glucose, plasma insulin and glucose tolerance were assessed. Further animal groups were used for in vitro GSIS and islet and liver gene expression analysis. Results and Conclusions: gkdel/wtmice showed early‐onset persistent hyperglycaemia, raised glycated haemoglobin levels, impaired GSIS and glucose tolerance but no change in plasma cholesterol, non‐esterified fatty acids or triglyceride levels. After HFD feeding, insulin levels of gkdel/wtmice were less than half that of gkwt/wtmice, although they were equivalent to gkwt/wtmice on CD. While gkwt/wtmice maintained moderate hyperglycaemia, gkdel/wtmice became overtly diabetic, with worsened glucose tolerance. A GKA (GKA50) increased GSIS, at 10 mM glucose, in gkdel/wtmice to an extent at least as great as that seen in gkwt/wtmice on both CD and HFD. gkdel/wtmice showed only a small number of changes in gene expression compared with gkwt/wtmice. We propose the high fat–fed gkdel/wtmouse as a model of type 2 diabetes and report retained efficacy of a GKA on in vitro GSIS.  相似文献   
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