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71.
Objective: To assess gender differences in the relationship between eating and weight loss attitudes (EWAs), and 30-day tobacco and alcohol use among adolescents, while controlling for potential confounds (age, country of birth, psychological distress, pubertal development, peer alcohol and tobacco use, and sexual activity). Methods: School students aged between 11 and 17 years (N = 10,273) from high schools in the State of Victoria (Australia) completed surveys in class under conditions of anonymity and confidentiality. Results: The interaction between EWAs and gender was significant for tobacco use but not for alcohol use, indicating that the effect of EWAs on tobacco use, but not alcohol use, vary by gender. Conclusions: Tobacco use was related to EWAs in adolescent females but not males, and this is consistent with the possibility that females use tobacco in an instrumental fashion to control weight. Implications and Contribution: Female adolescents high in eating and weight loss attitudes were more likely to engage in tobacco use. In contrast, eating and weight loss attitudes were not related to male tobacco use. These results point to the potential importance of developing gender-specific approaches towards addressing problematic behaviors in adolescent populations.  相似文献   
72.
中文:背景患者入院后可从不当消毒的环境表面获得多药耐药菌和艰难梭菌。本文确定了3种强化的终末消毒(入住同一病房的两名患者之间的消毒)策略,对感染耐甲氧西林金黄色葡萄球菌(MRSA)、耐万古霉素肠球菌(VRE)、艰难梭菌(CD)和多重耐药不动杆菌的影响。方法本文在美国东南部的9家医院开展了一项务实的、集群-随机、交叉研究。凡曾有感染或定植目标细菌感染患者居住过的病房,患者出院后随机采取4种消毒策略中的一种方法进行终末消毒:对照(季胺盐类消毒剂消毒,但凡遇到CD采用含氯消毒剂);UV(季胺盐类+UV-C消毒,但凡遇到CD采用含氯消毒剂+UV-C);含氯消毒剂;含氯消毒剂+UV-C。凡入住目标病房的患者被列为暴露人群。这4种终末消毒方法分别在每家医院连续实施7个月的周期。本文随机设计这几种消毒策略在每家医院内的实施顺序(1:1:1:1)。主要产出的结果是,观察暴露患者中目标细菌的感染的发生或定植情况,以及ITT人群中暴露患者CD感染发生率。本研究ClinicalTrials.gov注册编号:NCT01579370。结果共有31 226名患者暴露,其中21 395(69%)符合标准,包括4 916名对照组,5 178名UV组,5 438名含氯消毒剂组,以及5 863名含氯消毒剂+UV组。在对照组中,22 426个暴露日中有115名患者发生目标细菌的感染(51.3/10000暴露日)。在标准清洁策略的基础上增加UV消毒的暴露患者,其目标细菌感染的发生率明显较低(n=76;33.9/10 000暴露日;RR:0.70,95%CI:0.50~0.988;P=0.036)。含氯消毒剂组(n=101;41.6/10 000暴露日;RR:0.85,95%CI:0.69~1.04;P=0.116),或含氯消毒剂+UV组患者(n=131;45.6/10 000暴露日;RR:0.91,95%CI:0.76~1.09;P=0.303)的目标细菌的感染率,其差异无统计学意义。同样,在含氯消毒剂的基础上增加UV消毒,暴露患者中CD感染率也没有发生改变((n=38 vs 36;30.4 vs 31.6/10 000暴露日;RR:1.0,95%CI:0.57-1.75;P=0.997)。解释污染的医疗机构环境是获得病原微生物的重要来源;强化终末消毒可以降低这一风险。  相似文献   
73.
Population substructure can lead to confounding in tests for genetic association, and failure to adjust properly can result in spurious findings. Here we address this issue of confounding by considering the impact of global ancestry (average ancestry across the genome) and local ancestry (ancestry at a specific chromosomal location) on regression parameters and relative power in ancestry‐adjusted and ‐unadjusted models. We examine theoretical expectations under different scenarios for population substructure; applying different regression models, verifying and generalizing using simulations, and exploring the findings in real‐world admixed populations. We show that admixture does not lead to confounding when the trait locus is tested directly in a single admixed population. However, if there is more complex population structure or a marker locus in linkage disequilibrium (LD) with the trait locus is tested, both global and local ancestry can be confounders. Additionally, we show the genotype parameters of adjusted and unadjusted models all provide tests for LD between the marker and trait locus, but in different contexts. The local ancestry adjusted model tests for LD in the ancestral populations, while tests using the unadjusted and the global ancestry adjusted models depend on LD in the admixed population(s), which may be enriched due to different ancestral allele frequencies. Practically, this implies that global‐ancestry adjustment should be used for screening, but local‐ancestry adjustment may better inform fine mapping and provide better effect estimates at trait loci.  相似文献   
74.
The purpose of this clinical case report was to describe the kinematic variables of movement that best discriminated between asymmetrical and symmetrical mandibular excursion patterns in a patient with myogenic temporomandibular dysfunction. Two mandibular movements (deemed to be asymmetrical and symmetrical by both patient and physiotherapist) were each recorded six times on three occasions at six, twelve, and 15 weeks after commencement of an exercise programme. The mandibular movements were captured with a 12-camera Motion Analysis System (Motion Analysis Corp., Santa Rosa, CA) with kinematic variables expressed in six degrees-of-freedom. A two-way analysis of variance (ANOVA) for repeated measures was used to analyze the data. The asymmetrical pattern was characterized by increased axial rotation and decreased sagittal rotation but with no differences in translation values when compared to those of the symmetrical pattern. The results support the clinician's and patient's judgment regarding differences in quality of mandibular excursion patterns made over the course of time.  相似文献   
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77.

Background

Few previous studies have examined the influence of instrumental and emotional social support on physical activity (PA) longitudinally in underserved adolescents.

Purpose

This longitudinal study was a secondary analysis of the Active by Choice Today (ACT) trial examining whether instrumental social support predicts increases in PA in underserved adolescents, above and beyond emotional social support provided by family or peers.

Methods

Students in the sixth grade (N?=?1,422, 73 % African American, 54 % female, M age?=?11 years) in the ACT trial participated. At baseline and 19 weeks, previously validated measures of social support (family instrumental, family emotional, and peer emotional) were completed and moderate-to-vigorous PA (MVPA) was assessed using 7-day accelerometry estimates.

Results

A mixed ANCOVA demonstrated that baseline (p?=?0.02) and change in family instrumental support (p?=?0.01), but not emotional support from family or peers, predicted increases in MVPA across a 19-week period.

Conclusions

Future interventions in underserved adolescents should enhance opportunities for instrumental support for PA.  相似文献   
78.

Objective

The prefrontal cortex (PFC) receives multiple cortical and subcortical afferents that regulate higher order cognitive functions, many of which emerge late in adolescence. However, it remains unclear how these afferents influence PFC processing, especially in light of the protracted, late adolescent maturation of prefrontal GABAergic function. Here we investigated the role of PFC GABAergic transmission in regulating plasticity elicited from the ventral hippocampus and basolateral amygdala, and how such modulation undergoes functional changes during adolescence in rats.

Methods

In vivo local field potential recordings, combined with prefrontal microinfusion of the GABA-A receptor antagonist picrotoxin, were employed to study the impact of ventral hippocampal and basolateral amygdala high-frequency stimulation on PFC plasticity.

Results

Ventral hippocampal-induced PFC plasticity begins to appear only by postnatal days (P) 45–55 with a transient suppression of the evoked response. A switch from transient to long-lasting depression (LTD) of the PFC response emerges after P55 and throughout adulthood (P65–120). Recordings conducted in the presence of picrotoxin revealed that PFC GABAergic transmission is critical for the expression of LTD. In contrast, basolateral amygdala stimulation resulted in PFC long-term potentiation, a form of plasticity that is already enabled by P30 and is insensitive to picrotoxin.

Conclusions

The development of ventral hippocampal-dependent PFC LTD is contingent upon the recruitment of local prefrontal GABAergic transmission during adolescence whereas plasticity elicited from the basolateral amygdala is not. Thus, different mechanisms contribute to the refinement of prefrontal plasticity during adolescence as inputs from these two regions are critical for shaping PFC functions.  相似文献   
79.
Human metapneumovirus (HMPV) is an important cause of upper and lower respiratory tract disease in individuals of all ages. It is estimated that most individuals will be infected by HMPV by the age of five years old. Despite this burden of disease, there remain caveats in our knowledge of global genetic diversity due to a lack of HMPV sequencing, particularly at the whole-genome scale. The purpose of this study was to create a simple and robust approach for HMPV whole-genome sequencing to be used for genomic epidemiological studies. To design our assay, all available HMPV full-length genome sequences were downloaded from the National Center for Biotechnology Information (NCBI) GenBank database and used to design four primer sets to amplify long, overlapping amplicons spanning the viral genome and, importantly, specific to all known HMPV subtypes. These amplicons were then pooled and sequenced on an Illumina iSeq 100 (Illumina, San Diego, CA, USA); however, the approach is suitable to other common sequencing platforms. We demonstrate the utility of this method using a representative subset of clinical samples and examine these sequences using a phylogenetic approach. Here we present an amplicon-based method for the whole-genome sequencing of HMPV from clinical extracts that can be used to better inform genomic studies of HMPV epidemiology and evolution.  相似文献   
80.
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