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Individuals at clinical high risk (CHR) of developing psychosis present with widespread functional abnormalities in the brain. Cognitive deficits, including working memory (WM) problems, as commonly elicited by n-back tasks, are observed in CHR individuals. However, functional MRI (fMRI) studies, comprising a heterogeneous cluster of general and social cognition paradigms, have not necessarily demonstrated consistent and conclusive results in this population. Hence, a comprehensive review of fMRI studies, spanning almost one decade, was carried out to observe for general trends with respect to brain regions and cognitive systems most likely to be dysfunctional in CHR individuals. 32 studies were included for this review, out of which 22 met the criteria for quantitative analysis using activation likelihood estimation (ALE). Task related contrast activations were firstly analysed by comparing CHR and healthy control participants in the total pooled sample, followed by a comparison of general cognitive function studies (excluding social cognition paradigms), and finally by only looking at n-back working memory task based studies. Findings from the ALE implicated four key dysfunctional and distinct neural regions in the CHR group, namely the right inferior parietal lobule (rIPL), the left medial frontal gyrus (lmFG), the left superior temporal gyrus (lSTG) and the right fronto-polar cortex (rFPC) of the superior frontal gyrus (SFG). Narrowing down to relatively few significant dysfunctional neural regions is a step forward in reducing the apparent ambiguity of overall findings, which would help to target specific neural regions and pathways of interest for future research in CHR populations.  相似文献   
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Effective management of depression is predicated upon reliable assessment. The Quick Inventory of Depressive Symptomatology (QIDS) is a depression severity scale with both self-rated (QIDS-SR16) and clinician-rated (QIDS-C16) versions. Although widely used in research, the psychometric properties of the QIDS16 have not been systematically reviewed. We performed a systematic review of studies of the psychometric properties (factor structure, internal consistency, convergent validity, discriminant validity, test-retest reliability and responsiveness to change) of the QIDS-SR16 or QIDS-C16. Six databases were searched: MEDLINE, EMBASE, PsycINFO, CinAHL, Web of Science and the Cochrane Central Register of Controlled Trials. Findings were summarised, bias assessed and correlations with reference standards were pooled. 37 studies (17,118 participants) were included in the review. Both versions of the QIDS16 were unidimensional. Cronbach's alpha ranged from 0.69 to 0.89 for the QIDS-SR16 and 0.65 to 0.87 for the QIDS-C16. The QIDS-SR16 correlated moderately to highly with several depression severity scales. Seven studies were pooled where QIDS-SR16 was correlated with the HRSD-17 (r = 0.76, CI 0.69, 0.81) in patients diagnosed with depression. Four studies examined convergent validity with the QIDS-C16. Four studies examined discriminant validity, for the QIDS-SR16 alone. Eighteen studies had at least one author who was a co-author of the original QIDS16 study. Most studies were conducted in the USA (n = 26). The QIDS-SR16 and the QIDS-C16 are unidimensional rating scales with acceptable internal consistency. To justify the use of the QIDS16 scale in clinical practice, more research is needed on convergent and discriminant validity, and in populations outside the USA.  相似文献   
4.
BackgroundSuicide claims one million lives worldwide annually, making it a serious public health concern. The risk for suicidal behaviour can be partly explained by genetic factors, as suggested by twin and family studies (reviewed in (Zai et al. 2012)). Recently, genome-wide association studies (GWASs) of suicide attempt on large samples of bipolar disorder (BD) patients from multiple sites have identified a number of novel candidate genes. GWASs of suicide behaviour severity, from suicidal ideation to serious suicide attempt, have not been reported for BD.MethodsWe conducted a GWAS of suicide behaviour severity in three independent BD samples:212 small nuclear families with BD probands from Toronto, Canada, 428 BD cases from Toronto, and 483 BD cases from the UK. We carried out imputation with 1000 Genome Project data as reference using IMPUTE2. Quality control and data analysis was conducted using PLINK and R. We conducted the quantitative analyses of suicide behaviour severity in the three samples separately, and derived an overall significance by a meta-analysis using the METAL software.ResultsWe did not find genome-wide significant association of any tested markers in any of the BD samples, but we found a number of suggestive associations, including regions on chromosomes 8 and 10 (p < 1e-5).ConclusionsOur GWAS findings suggest that likely many gene variants of small effects contribute collectively to the risk for suicidal behaviour severity in BD. Larger independent replications are required to strengthen the findings from the GWAS presented here.  相似文献   
5.
Consistent evidence indicates that exercise improves cognition and mood, with preliminary evidence suggesting that brain-derived neurotrophic factor (BDNF) may mediate these effects. The aim of the current meta-analysis was to provide an estimate of the strength of the association between exercise and increased BDNF levels in humans across multiple exercise paradigms. We conducted a meta-analysis of 29 studies (N = 1111 participants) examining the effect of exercise on BDNF levels in three exercise paradigms: (1) a single session of exercise, (2) a session of exercise following a program of regular exercise, and (3) resting BDNF levels following a program of regular exercise. Moderators of this effect were also examined. Results demonstrated a moderate effect size for increases in BDNF following a single session of exercise (Hedges' g = 0.46, p < 0.001). Further, regular exercise intensified the effect of a session of exercise on BDNF levels (Hedges' g = 0.59, p = 0.02). Finally, results indicated a small effect of regular exercise on resting BDNF levels (Hedges' g = 0.27, p = 0.005). When analyzing results across paradigms, sex significantly moderated the effect of exercise on BDNF levels, such that studies with more women showed less BDNF change resulting from exercise. Effect size analysis supports the role of exercise as a strategy for enhancing BDNF activity in humans, but indicates that the magnitude of these effects may be lower in females relative to males.  相似文献   
6.
Alcohol addiction may increase the risk of obesity due to shared genetic components. The Copine V (CPNE5) gene is involved in Ca2+ binding and may play an important role in the development of the central nervous system. This study tested the genetic associations of 77 single-nucleotide polymorphisms (SNPs) within the CPNE5 gene with alcohol dependence (AD) and obesity using a Caucasian sample – The Study of Addiction – Genetics and Environment (SAGE) sample (1066 AD cases and 1278 non-AD controls, 422 obese cases and 1395 non-obese controls). The Marshfield sample (1442 obese cases and 2122 non-obese controls) was used for replication of obesity. Multiple logistic regression analysis was performed using the PLINK software. In the SAGE sample, we identified 10 SNPs associated with AD and 17 SNPs associated with obesity (p < 0.05). Interestingly, 6 SNPs (rs9986517, rs9470387, rs3213534, rs10456444, rs3752482, and rs9470386) were associated with both AD (OR = 0.77, 0.77, 0.83, 0.84, 0.79 and 1.14, respectively; p = 9.72 × 10−5, 1.1 × 10−4, 4.09 × 10−3, 5.26 × 10−3, 1.59 × 10−2, and 3.81 × 10−2, respectively) and obesity (OR = 0.77, 0.77, 0.78, 0.77, 0.68 and 1.18, respectively; p = 2.74 × 10−3, 2.69 × 10−3, 2.45 × 10−3, 1.01 × 10−3, 5.18 × 10−3 and 3.85 × 10−2, respectively). In the Marshfield sample, rs3752480 was associated with obesity (p = 0.0379). In addition, four SNPs (rs9986517, rs10456444, rs7763347 and rs4714010) showed associations with obesity in the meta-analysis using both samples (p = 0.00493, 0.0274, 0.00346, and 0.0141, respectively). These findings provide the first evidence of common genetic variants in the CPNE5 gene influencing both the AD and obesity; and will serve as a resource for replication in other populations.  相似文献   
7.
Inconsistent results in neuropsychological research of obsessive-compulsive disorder (OCD) may be the result of the heterogeneous nature of OCD symptoms. The most frequently investigated symptoms are contamination/cleaning and doubt/checking. The aim of this review was to determine whether OCD washers and checkers differ in their neuropsychological performance. We conducted a meta-analysis of 13 studies (including 535 patients) comprising tests in 10 different neuropsychological domains. Washers showed significant better task performance than checkers in 8 of 10 cognitive domains. Large effect sizes were found in planning/problem solving and response inhibition. Effect size in set shifting was medium, whereas effect sizes in attention, processing speed, encoding, verbal memory and nonverbal memory were small. Limitations consisted in a relatively small number of primary studies. In line with current neurobiological findings, the results provide further evidence for the validity of different symptom dimensions in OCD. Clinical and theoretical implications are discussed.  相似文献   
8.
Literature on posttraumatic stress disorder (PTSD) prevalence among Operations Enduring Freedom and Iraqi Freedom (OEF/OIF) veterans report estimates ranging from 1.4% to 60%. A more precise estimate is necessary for projecting healthcare needs and informing public policy. This meta-analysis examined 33 studies published between 2007 and 2013 involving 4,945,897 OEF/OIF veterans, and PTSD prevalence was estimated at 23%. Publication year and percentage of Caucasian participants and formerly active duty participants explained significant variability in prevalence across studies. PTSD remains a concern for a substantial percentage of OEF/OIF veterans. To date, most studies have estimated prevalence among OEF/OIF veterans using VA medical chart review. Thus, results generalize primarily to the prevalence of PTSD in medical records of OEF/OIF veterans who use VA services. Additional research is needed with randomly selected, representative samples administered diagnostic interviews. Significant financial and mental health resources are needed to promote recovery from PTSD.  相似文献   
9.
Since studies of association between prenatal tobacco exposure and age at menarche have reported inconsistent results so far, we conducted a meta-analysis to examine this association. In total 36 relevant articles (1995–2014) were identified, 17 of which satisfied the inclusion criteria and were used in the analysis. Nearly one month decrease (−0.092 [95% CI:−0.160, −0.024] year) in age at menarche was found in women who were exposed to tobacco in utero. The meta-regression analysis showed that average year of birth in the cohorts might significantly influence association between maternal smoking and daughter’s age at menarche. Based on results obtained from 5 studies where age at menarche was treated as a categorical variable, maternal smoking status during pregnancy increased a risk for daughters to have menarche earlier than at 11 years old by 15%.  相似文献   
10.
目的 评价绿脓杆菌注射液(pseudomonas aeruginosa injection,PAI)辅助治疗恶性肿瘤的临床疗效和安全性。方法 通过检索Cochrane Library、PubMed、Embase、CBM、CNKI、VIP和万方数据库,纳入相关的随机对照试验(randomized controlledtrail,RCT)。采用Jadad评分评价文献质量,使用Revman 5.3进行数据合并和分析。结果 纳入14项RCT,合计1 036例患者,其中PAI组526例,对照组510例。PAI组在疾病完全缓解率[RR=1.64,95%CI(1.34,2.00),P<0.000 1]、疾病部分缓解率[RR=1.31,95%CI(1.12,1.53),P=0.000 6]、疾病稳定率[RR=0.35,95%CI (0.26,0.48),P<0.000 1]和疾病进展(PD)率[RR=0.45,95%CI (0.27,0.74),P<0.000 1]方面与对照组有显著性差异。在不良反应方面,PAI显著增加了发热和皮肤局部反应的发生率,而2组在胸痛方面无显著性差异。结论 在常规手术和放化疗的基础上加用绿脓杆菌注射液辅助治疗恶性肿瘤时,虽然其增加了发热和皮肤局部反应的风险,但并无严重不良反应存在,同时可在一定程度上改善临床相关的指标。  相似文献   
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