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BackgroundCausal risk factors for aortic valve stenosis are poorly understood, limiting the possibility of preventing the most common heart valve disease.ObjectivesThe hypothesis was tested that genetically based obesity measured by body mass index is causally associated with risk of aortic valve stenosis and replacement.MethodsThe authors included 108,211 individuals from the Copenhagen General Population Study. Participants had measurements of body mass index, waist-hip ratio, and waist circumference, and information on 5 genetic variants associated with obesity. A Mendelian randomization design was used to investigate genetic and observational associations of obesity with incident aortic valve stenosis (n = 1,215) and replacement (n = 467) for a median follow-up time of 8.7 years.ResultsGenetically increased body mass index was causally associated with increased risk of aortic valve stenosis. Compared with an unweighted allele score of 0 to 3, individuals with an allele score 7 to 10 had a mean increase in body mass index of 0.87 kg/m2, and the age and sex–adjusted hazard ratio for aortic valve stenosis was 1.3 (95% confidence interval [CI]: 1.0 to 1.7) for allele score 4, 1.4 (95% CI: 1.1 to 1.8) for allele score 5 to 6, and 1.6 (95% CI: 1.3 to 2.1) for allele score 7 to 10 (p for trend: 9 × 10−5). A 1-kg/m2 increase in body mass index was associated with causal risk ratios for aortic valve stenosis and replacement, respectively, of 1.52 (95% CI: 1.23 to 1.87) and 1.49 (95% CI: 1.07 to 2.08) genetically, and with corresponding hazard ratios of 1.06 (95% CI: 1.05 to 1.08) and 1.06 (95% CI: 1.03 to 1.08) observationally.ConclusionsObesity from human genetics was causally associated with higher risk of aortic valve stenosis and replacement.  相似文献   
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Attitudes and expectations of people towards their lives are essential to future health outcomes. Growing evidence has linked dispositional optimism to beneficial health outcomes, such as exceptional longevity, healthy aging and better sleep quality. We describe the association between dispositional optimism and chronic insomnia, considering potential mediators, in the Austrian Sleep Survey (N = 1,004), a population‐based cross‐sectional study conducted in 2017. Optimism was measured using the validated Life Orientation Test‐Revised, and four different definitions were used to assess chronic insomnia. Three definitions were based on the criteria of chronic insomnia according to the International Classification of Sleep Disorders (3rd edn). Age‐ and multivariable‐adjusted logistic regression models were used to calculate odds ratios (OR) and 95% confidence intervals (CIs). Among Austrians who were more optimistic, chronic insomnia risk was lower compared with those less optimistic (middle versus bottom tertile of optimism score: OR = 0.39, 95% CI, 0.22–0.70; and top versus bottom tertile: OR = 0.28, 95% CI, 0.14–0.54; p‐trend < .001). Results were similar for all four definitions of insomnia, and differed slightly between men and women. Happiness, depression and health status confounded the association, whereas lifestyle did not. Promoting dispositional optimism could represent a simple and accessible strategy to improve sleep quality and lower insomnia risk, with downstream beneficial health effects. Further research is needed to clarify the prevention potential of interventions targeting this mental trait.  相似文献   
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Background: Type 2 diabetes mellitus (T2DM) is a complex chronic metabolic disorder triggered by insulin resistance in peripheral tissues. Evidence has shown that lipid metabolism and related genetic factors lead to insulin resistance. Hence, it is meaningful to investigate the association between single-nucleotide polymorphisms (SNPs) in lipid metabolism-related genes and T2DM.Methods: A total of 1,194 subjects with T2DM and 1,274 Non-diabetic subjects (NDM) were enrolled. Five SNPs in three genes (rs864745 in JAZF1, rs35767 in IGF1, and rs4376068, rs4402960, and rs6769511 in IGF2BP2) that contribute to insulin resistance involving lipid metabolism were genotyped using the MassArray method in a Chinese population.Results: The allele and genotypes of rs6769511 in IGF2BP2 were associated with T2DM (P=0.009 and P=0.002, respectively). In inheritance model analysis, compared with the T/T-C/T genotype, the C/C genotype of rs6769511 in IGF2BP2 was a risk factor for the development of T2DM (P<0.001, odds ratio [OR] =1.76; 95% confidence interval [CI]: 1.29-2.42). Haplotype analysis revealed associations of the rs4376068-rs4402960-rs6769511 haplotypes in IGF2BP2 with the development of T2DM (P=0.015). Additionally, rs4376068C-rs4402960T-rs6769511C was a risk haplotype for T2DM (OR=1.179; 95% CI: 1.033-1.346).Conclusion: The rs6769511 in IGF2BP2 was associated with T2DM susceptibility, and the rs4376068-rs4402960-rs6769511 haplotypes in IGF2BP2 was associated with the development of T2DM in a Chinese population.  相似文献   
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ObjectiveTo determine various morphometric parameters like transverse and sagittal pedicle width; interpedicular distance; antero-posterior and transverse canal diameter and canal surface area at thoracolumbar junction (T11, T12, L1, L2) in central Indian population and compare results with similar studies available in literature.Material and methodsA prospective, computerized tomography scan based morphometric analysis of thoracolumbar junction was conducted at medical college and tertiary care centre in central India. All asymptomatic cases more than 18 years age with normal lateral radiograph and CT scan of thoracolumbar junction and free from any spinal pathology or trauma were included in the study. Parameters measured were transverse and sagittal pedicle width; interpedicular distance; antero-posterior and transverse canal diameter and canal surface area at thoracolumbar junction (T11, T12, L1, L2).ResultsMean transverse pedicle width was maximum at T11 and minimum at L1 in both males and females, whereas sagittal width was maximum at T11 and minimum at L2 in both the groups. Interpedicular distance was largest at L1 in both the groups. All the measurements were significantly different (P < 0.05) in males and females. Mean antero-posterior and transverse diameter was maximum at T12 and L2 respectively in both male and female study population. Canal surface area was maximum at L1 among males (230.10 mm2) as well as females (209.02 mm2).ConclusionThere is significant variation in morphometric parameters of thoracolumbar junction in different races and population. Thorough knowledge of morphometry of a particular population is essential for dealing with pathology or trauma of thoracolumbar junction.  相似文献   
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ObjectiveThe purposes of the present study were to explore independent and interactive associations between night sleep duration, night sleep quality and coronary heart disease (CHD) based on a rural population in China.MethodsA total of 27,935 participants (11,177 men and 16,758 women) were investigated from the Henan Rural Cohort. Information about sleep was assessed by using the Pittsburgh Sleep Quality Index (PSQI). Restricted cubic splines and logistic regression were used to estimate the relationship between night sleep duration and quality with CHD.ResultAmong the 27,935 participants, 1506 participants with CHD were identified. Compared with participants with scores lower than 3, the odds ratios (ORs) and 95% confidence intervals (95% CIs) of participants with score of 3–5, 6–8, ≥9 were respectively 1.42 (1.24–1.63), 1.99 (1.70–2.33), and 2.56 (2.13–3.08) with full adjustment of covariates. Compared with night sleep duration of 7 h, men and women who slept less than 5 h were 1.55 (1.11–2.17), 1.12 (0.59–2.12) and 1.80 (1.20–2.68), after being adjusted ORs (95% CIs) of the total. Moreover, the ORs and 95% CIs of CHD increased with the shortening of sleep duration at PSQI score above the highlighted levels.ConclusionPoor sleep quality and short night sleep duration were all associated with CHD in Chinese rural areas. Moreover, the association was more obvious in women. In addition, the strongest prevalence of CHD was found in short sleepers with poor sleep quality.  相似文献   
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Background and aimsSome amino acids (AAs) may be associated with type 2 diabetes (T2DM). This study aimed to determine the associations of individual AAs with the development of T2DM in rural Chinese adults.Methods and resultsA cohort study of 1199 individuals aged 18 years or older was conducted from 2006 to 2008 in a rural community of Deqing, China, a repeated survey was done in 2015 and data linkage with the electronic health records system was performed each year for identifying new T2DM cases. A high-performance liquid chromatography approach was used to measure the baseline serum concentrations of 15 AAs. Cox proportional hazards models were used to examine the associations between AAs and the risk of incident T2DM. A total of 98 new T2DM cases were identified during the follow-up of 12 years on average. Among 15 AAs, proline was associated with an increased risk of incident T2DM after adjusted for age, sex, body mass index, fasting plasma glucose, family history of T2DM, smoking status, alcohol use, and history of hypertension, the adjusted hazard ratio for 1-standard deviation increment was 1.20 (95% confidence interval: 1.00, 1.43). The association tended to be more marked in subjects younger than 60 years and overweight/obese subjects. Among participants without hypertension, proline and phenylalanine were associated with an increased risk of incident T2DM, while aspartic acid was associated with a decreased risk.ConclusionSerum proline was associated with the risk of incident T2DM in rural Chinese adults and might be a potential predictor.  相似文献   
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