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91.

Purpose

We investigated maternal genetic effects of four IL-4/IL-13 pathway genes as well as their interactions with the "Western or Eastern lifestyles/environments" on IgE in Karelian children.

Methods

This study included 609 children and their mothers. Total IgE levels in children and mothers were measured and 10 single nucleotide polymorphisms (SNPs) in IL-4, IL-4Ra, IL-13, and STAT6 were genotyped in mothers and their children.

Results

The maternal G allele of IL-13 130 (rs20541) was significantly (P=0.001) associated with decreased IgE in children in the Karelian population (Pooling Finnish and Russian children), as well as in Finnish (P=0.030) and Russian children (P=0.018). The IgE levels were significantly (P=0.001) higher in Russian children whose mothers were homozygous for the G allele of the IL-4Ra 50 (rs1805010) SNP than that in Russian children of mothers who were AG heterozygotes or AA homozygotes. After accounting for children''s genotypes, we observed interactive effects on children''s IgE for maternal IL-13 130 genotypes (P=0.014) and maternal IL-4Ra 50 genotypes (P=0.0003) with "Western or Eastern" lifestyles/environments. With the adjustment for multiple comparisons using a false discovery rate (FDR) of 0.05, the interactive effect of the maternal IL-4Ra50 SNP was significant.

Conclusion

Maternal genetic variants in IL-4/IL-13 pathway genes, such as IL-13 130 and IL-4Ra50, influenced IgE levels in school children that were independent of the children''s genetic effects. These effects differ in "Western or Eastern" environments.  相似文献   
92.
The addition of 0.2 mM Na L-ascorbate increased the incorporation of 3H-thymidine by rabbit articular chondrocytes in cell and organ culture. The stimulatory response of explants to ascorbate was potentiated by pretreatment of the cartilage with 0.2% clostridial collagenase (type 1) or trypsin for 15–30 minutes. In explants there was a latent period of 3 to 4 days before increased labeling of the nuclei could be detected. The effect was transient and declined after 8 days of culture. It was more evident in organ cultures of immature (3-month-old) than 2- to 3-year-old rabbits. Age differences were not detected in cell cultures. Explants of adult human articular cartilage were stimulated by ascorbate when the medium was supplemented with 10% fresh human serum but not by fetal bovine serum. The findings indicated that synthesis of DNA by articular chondrocytes in situ is regulated by responsiveness of the cells proper to compounds such as vitamin C, by properties of the extracellular matrix, and by factors in the serum. Ascorbate was cytotoxic at concentrations >0.2 mM in the presence of certain batches of serum and when added to monolayers before the cells attached to the surface of the flask.  相似文献   
93.
94.
INTRODUCTIONChest radiographs (CXRs) are widely used for the screening and management of COVID-19. This article describes the radiographic features of COVID-19 based on an initial national cohort of patients.METHODSThis is a retrospective review of swab-positive patients with COVID-19 who were admitted to four different hospitals in Singapore between 22 January and 9 March 2020. Initial and follow-up CXRs were reviewed by three experienced radiologists to identify the predominant pattern and distribution of lung parenchymal abnormalities.RESULTSIn total, 347 CXRs of 96 patients were reviewed. Initial CXRs were abnormal in 41 (42.7%) out of 96 patients. The mean time from onset of symptoms to CXR abnormality was 5.3 ± 4.7 days. The predominant pattern of lung abnormality was ground-glass opacity on initial CXRs (51.2%) and consolidation on follow-up CXRs (51.0%). Multifocal bilateral abnormalities in mixed central and peripheral distribution were observed in 63.4% and 59.2% of abnormal initial and follow-up CXRs, respectively. The lower zones were involved in 90.2% of initial CXRs and 93.9% of follow-up CXRs.CONCLUSIONIn a cohort of swab-positive patients, including those identified from contact tracing, we found a lower incidence of CXR abnormalities than was previously reported. The most common pattern was ground-glass opacity or consolidation, but mixed central and peripheral involvement was more common than peripheral involvement alone.  相似文献   
95.
Nasopharyngeal carcinoma (NPC) is originated from the epithelial cells of nasopharynx, Epstein–Barr virus (EBV)-associated and has the highest incidence and mortality rates in Southeast Asia. Late presentation is a common issue and early detection could be the key to reduce the disease burden. Sensitivity of plasma EBV DNA, an established NPC biomarker, for Stage I NPC is controversial. Most newly reported NPC biomarkers have neither been externally validated nor compared to the established ones. This causes difficulty in planning for cost-effective early detection strategies. Our study systematically evaluated six established and four new biomarkers in NPC cases, population controls and hospital controls. We showed that BamHI-W 76 bp remains the most sensitive plasma biomarker, with 96.7% (29/30), 96.7% (58/60) and 97.4% (226/232) sensitivity to detect Stage I, early stage and all NPC, respectively. Its specificity was 94.2% (113/120) against population controls and 90.4% (113/125) against hospital controls. Diagnostic accuracy of BamHI-W 121 bp and ebv-miR-BART7-3p were validated. Hsa-miR-29a-3p and hsa-miR-103a-3p were not, possibly due to lower number of advanced stage NPC cases included in this subset. Decision tree modeling suggested that combination of BamHI-W 76 bp and VCA IgA or EA IgG may increase the specificity or sensitivity to detect NPC. EBNA1 99 bp could identify NPC patients with poor prognosis in early and advanced stage NPC. Our findings provided evidence for improvement in NPC screening strategies, covering considerations of opportunistic screening, combining biomarkers to increase sensitivity or specificity and testing biomarkers from single sampled specimen to avoid logistic problems of resampling.  相似文献   
96.
Objective  This study was designed to determine the safety of nevirapine (NVP)-based highly active antiretroviral therapy (HAART) in a cohort of HIV-positive pregnant women.
Design  This was a prospective cohort study of HIV-positive pregnant women.
Population and setting  All HIV-positive women treated with HAART during pregnancy from January 1997 to February 2004 at the British Columbia (BC) Women's Hospital in Vancouver, BC, Canada.
Methods  Demographic and clinical data were collected to compare antiretroviral drug toxicities in women treated antenatally with NVP-based or non-NVP-based HAART. Multivariate analyses were then used to investigate determinants of toxicity.
Results  From 1997 to 2004, 103 HIV-positive pregnant women received HAART. Equivalent numbers of women were initially treated with NVP-based (54%) and non-NVP-based (46%) HAART. The groups did not differ by clinical or demographic parameters and duration of HAART exposure was similar between groups. Toxicities necessitating treatment discontinuation were observed in 6 of 56 NVP-exposed women (2 cases each of grade 2, 3, and 4 toxicity) compared with 1 of 47 in the non-NVP-exposed women. First time use of NVP approached significance as a predictor for toxicity, with a toxicity rate of 12.5% (6/48) observed among those taking NVP for the first time (adjusted OR 2.68, 95% CI 0.49–14.6).
Conclusion  Continuous NVP use in pregnancy resulted in a relatively higher rate of toxicity, and all cases of NVP toxicity occurred in women exposed to NVP for the first time during pregnancy.  相似文献   
97.
Previous pilot work has established an association between obstructive sleep apnoea and the development of acute postoperative delirium 1 - 3 , but it remains unclear to what extent this risk factor is modifiable in the ‘real world’ peri‐operative setting. In a single‐blind randomised controlled trial, 135 elderly surgical patients at risk for obstructive sleep apnoea were randomly assigned to receive peri‐operative continuous positive airway pressure (CPAP) or routine care. Of the 114 patients who completed the study, 21 (18.4%) experienced delirium. Delirium was equally common in both groups: 21% (12 of 58 subjects) in the CPAP group and 16% (9 of 56 subjects) in the routine care group (OR = 1.36 [95%CI 0.52–3.54], p = 0.53). Delirious subjects were slightly older – mean (SD) age 68.9 (10.7) vs. 64.9 (8.2), p = 0.07 – but had nearly identical pre‐operative STOP‐Bang scores (4.19 (1.1) versus 4.27 (1.3), p = 0.79). Subjects in the CPAP group used their devices for a median (IQR [range]) of 3 (0.25–5 [0–12]) nights pre‐operatively (2.9 (0.1–4.8 [0.0–12.7]) hours per night) and 1 (0–2 [0–2]) nights postoperatively (1.4 (0.0–5.1 [0.0–11.6]) hours per night). Among the CPAP subjects, the residual pre‐operative apnoea–hypopnea index had a significant effect on delirium severity (p = 0.0002). Although we confirm that apnoea is associated with postoperative delirium, we did not find that providing a short‐course of auto‐titrating CPAP affected its likelihood or severity. Voluntary adherence to CPAP is particularly poor during the initiation of therapy.  相似文献   
98.
99.
The human working memory system provides an experimentally useful model for examination of neural overload effects on subsequent functioning of the overloaded system. This study employed functional magnetic resonance imaging in conjunction with a parametric working memory task to characterize the behavioral and neural effects of cognitive overload on subsequent cognitive performance, with particular attention to cognitive-limbic interactions. Overloading the working memory system was associated with varying degrees of subsequent decline in performance accuracy and reduced activation of brain regions central to both task performance and suppression of negative affect. The degree of performance decline was independently predicted by three separate factors operating during the overload condition: the degree of task failure, the degree of amygdala activation, and the degree of inverse coupling between the amygdala and dorsolateral prefrontal cortex. These findings suggest that vulnerability to overload effects in cognitive functioning may be mediated by reduced amygdala suppression and subsequent amygdala-prefrontal interaction.  相似文献   
100.
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