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In this study the visual working memory (VWM) and perception speed of 60 children between the ages of three and six years were tested with an age-based, easy-to-handle Matrix Film Battery Test (reliability R?=?.71). It was thereby affirmed that the VWM is age dependent (correlation coefficient r?=?.66***) as expected. Furthermore, a significant gender effect was found (partial correlation coefficient rp?=?.42***) indicating that boys generally have a better VWM: they are able to memorise more items and they can process visual information faster. Given that the test was repeated during a period of eight months, strong learning effects could be detected which show that the VWM can be trained and that the test itself is also a good training tool.  相似文献   
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AIMS: This study addressed the hypotheses that the hypercapnic flow response in wild-type (WT) mouse heart is mainly mediated by nitric oxide (NO) and, thus, severely blunted in endothelial nitric oxide synthase knockout (eNOS-KO) mice and in WT mice after continuous pharmacological block (2 weeks) of NOS enzymes (WT-LN). METHODS AND RESULTS: Step changes of arterial pCO(2) were performed in isolated perfused hearts (n = 105). Contributions of NOS (L-NAME, TRIM), cyclooxygenase (indomethacin), epoxyeicosanotrienes (miconazole), adenosine A2A-receptors (SCH 58261), KV-channels (4-AP), KCa-channels (TEA), and K ATP-channels (glibenclamide) were studied in WT and eNOS-KO mouse hearts. Change of arterial pCO(2) increased coronary flow by 31.3 +/- 4% in WT, a response that was significantly decreased to 9.2 +/- 6% after L-NAME. Additional glibenclamide infusion (n = 5) completely abolished the steady-state flow increase during hypercapnic acidosis (-4.2 +/- 2.3%, P = 0.004 vs. control). Hearts from eNOS-KO mice as well as WT-LN showed a fully preserved flow response insensitive towards NOS-blockade. Whereas indomethacin, miconazole, TEA, and SCH 58261 were ineffective to reduce the flow response, glibenclamide blunted it in eNOS-KO hearts. CONCLUSION: NO-production and K ATP-channel activation together may fully account for the steady-state hypercapnic flow response in mouse heart. However, chronic deletion of eNOS does not result in a reduced hypercapnic flow response. Enhanced activation of K ATP-channels and potentially Kv-channels contributes to the compensatory mechanisms involved in the hypercapnic flow response when eNOS activity is absent.  相似文献   
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Laser Doppler flowmetry (LDF) is frequently used to study the microcirculation. Usually LDF time series are analyzed by conventional linear methods, mainly Fourier analysis. The aim of this study was to observe dynamic blood perfusion of the skin in malignant and benign melanocytic skin lesions. Wavelet transformation was performed on each LDF time series in order to calculate a vasomotion field. First, the differences in vasomotion between healthy and pigmented skin were evaluated visually on six different time scales of the vasomotion field. In order to quantify the findings, vasomotion scale variance (VSV) was calculated for each scale plane of the vasomotion field. These VSV were compared using contrast DeltaVSV to determine the difference between healthy skin and a pigmented skin lesion in the same patient. After the measurements, the skin lesions were excised and examined histologically. We found that wavelet analysis of LDF time series is a specific, sensitive method for the in vivo identification of malignant melanoma. It is a non-invasive procedure and takes minimal time to be carried out.  相似文献   
45.
The probability of event-free survival of childhood acute lymphoblastic leukemia (ALL) approaches 80% or more with the use of modern multiagent chemotherapeutic regimens. One major contribution to this success has been reduction of the rate of central nervous system (CNS) relapses to less than 5%. However, heterogeneity is observed with regard to the incidence of CNS relapse in homogenously treated patient populations. One potential explanation for this heterogeneity is variation in the genetic background of these populations. Glutathione S-transferase P1 and P-glycoprotein are implicated in resistance to a variety of chemotherapeutic agents and have been localized to the blood-brain barrier. In a matched case-control study, we investigated the associations between CNS relapse in childhood ALL and the presence of phenotypically relevant single nucleotide polymorphisms within the GSTP1 (codon 105 and 114) and MDR1 genes (ABCB1; coding for Pgp; exon 26, C3435T). Significant reductions in risk of CNS relapse were observed for patients homozygous for the GSTP1 Val105 allele as well as for patients with the MDR1 3435T/T or C/T genotype. For both genotypes, the effect was restricted to patients at intermediate or high risk of treatment failure. These results suggested a modulating role for host genetic variation in the development of CNS relapse in childhood ALL treated according to Berlin-Frankfurt-Münster protocols.  相似文献   
46.
To compare human immunodeficiency virus (HIV) type 1 disease progression in patients infected by the predominant strain circulating recombinant form (CRF) 02_AG in western and west-central Africa and in patients infected by other strains, a prospective multicenter cohort study was conducted in Cameroon and Senegal. Among the 335 patients, a broad HIV-1 group M subtype diversity was observed in the envelope V3-V5 region, but strain CRF02_AG predominated in both Cameroon and Senegal (61.2% and 62.9%, respectively; P<.8). Multivariate analyses showed no difference between patients infected by CRF02 strains and those infected by other strains in terms of survival (adjusted hazards ratio [HR], 1.16; 95% confidence interval [CI], 0.76-1.78; P=.5), clinical disease progression (HR, 0.79; 95% CI, 0.50-1.25; P=.3), or square root CD4 cell decline (regression coefficient, -0.01; 95% CI, -0.82 to 0.81; P=.9). This study suggests that the predominance of HIV-1 CRF02_AG strain in western and west-central Africa should have no major clinical consequences.  相似文献   
47.

Background and Purpose

A direct comparison between the effects of constraint‐induced movement therapy (CIMT) applied early after stroke and that of CIMT applied in the chronic phase has not been conducted. This study aimed to compare the long‐term effects of CIMT applied 6 months after stroke with the results of CIMT applied within 28 days post‐stroke.

Methods

This study was a single‐blinded, multicentre, randomized controlled trial with a crossover design. Forty‐seven patients received CIMT either early (within 28 days) or 6 months after stroke. Both groups received standard rehabilitation and were tested at 5 time points. The primary outcome measure was Wolf Motor Function Test (WMFT); the secondary measures were Nine‐Hole Peg Test (NHPT), the Fugl‐Meyer Assessment (FMA) of the upper extremity, Stroke Impact Scale, and Modified Rankin Scale (MRS).

Results

Compared with baseline data, both groups showed significant improvements in the primary and secondary outcome measures after 12 months. No significant differences between the 2 treatment groups were found before and after the delayed intervention group received CIMT at 6 months and during the 12‐month follow‐up. Both groups recovered considerably and showed only minor impairment (median FMA score of 64) after 6 months. The early intervention group showed an initially faster recovery curve of WMFT, NHPT, and MRS scores.

Discussion

In contrast to most CIMT studies, our study could not find an effect of CIMT applied 6 months after stroke. Our results indicate that commencing CIMT early is as good as delayed intervention in the long term, specifically in this group of patients who might have reached a ceiling effect during the first 6 months after stroke. Nevertheless, the early CIMT intervention group showed a faster recovery curve than the delayed intervention group, which can be a clinically important finding for patients in the acute phase.  相似文献   
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