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991.

Background

Effort-reward imbalance (ERI) is an established conceptualisation of work stress. Although a validated effort-reward questionnaire is available for public use, many epidemiological studies adopt shortened scales and proxy measures. To examine the agreement between different abbreviated measures and the original instrument, we compared different versions of the effort-reward scales available in 15 European cohort studies participating in the IPD-Work (Individual-participant-data meta-analysis in working populations) consortium.

Methods

Five of the 15 studies provide information on the original (‘complete’) scales measuring ‘effort’ and ‘reward’, whereas the 10 remaining studies used ‘partial’ scales. To compare different versions of the ERI scales, we analyse individual-level data from 31,790 participants from the five studies with complete scales.

Results

Pearson’s correlation between partial and complete scales was very high in case of ‘effort’ (where 2 out of 3 items were used) and very high or high in case of ‘reward’, if at least 4 items (out of 7) were included. Reward scales composed of 3 items revealed good to satisfactory agreement, and in one case, a reward scale consisting of 2 items only demonstrated a modest, but still acceptable degree of agreement. Sensitivity and specificity of a composite measure, the ratio of effort and reward, comparing partial versus complete scales ranged between 59–93 and 85–99 %, respectively. Complete and partial scales were strongly associated with poor self-rated health.

Conclusion

Our results support the notion that short proxy measures or partial versions of the original scales can be used to assess effort-reward imbalance.  相似文献   
992.
The concept of brain maintenance refers to the preservation of brain integrity in older age, while cognitive reserve refers to the capacity to maintain cognition in the presence of neurodegeneration or aging‐related brain changes. While both mechanisms are thought to contribute to individual differences in cognitive function among older adults, there is currently no “gold standard” for measuring these constructs. Using machine‐learning methods, we estimated brain and cognitive age based on deviations from normative aging patterns in the Whitehall II MRI substudy cohort (N = 537, age range = 60.34–82.76), and tested the degree of correspondence between these constructs, as well as their associations with premorbid IQ, education, and lifestyle trajectories. In line with established literature highlighting IQ as a proxy for cognitive reserve, higher premorbid IQ was linked to lower cognitive age independent of brain age. No strong evidence was found for associations between brain or cognitive age and lifestyle trajectories from midlife to late life based on latent class growth analyses. However, post hoc analyses revealed a relationship between cumulative lifestyle measures and brain age independent of cognitive age. In conclusion, we present a novel approach to characterizing brain and cognitive maintenance in aging, which may be useful for future studies seeking to identify factors that contribute to brain preservation and cognitive reserve mechanisms in older age.  相似文献   
993.
Abstract – Background: There is limited and inconsistent evidence on the influence of residential setting on caries experience of adults with physical and intellectual disabilities (PID), described here as care‐recipients. Objective: To examine caries experience and associated factors among adults with PID. Methods: Mailed questionnaire survey (2005–2006) of carers of adults with PID (18–44 years) in South Australia from family homes, community housing, and institutions, and oral examinations of care‐recipients recording decayed (D), missing (M) and filled (F) teeth (DMFT). Results: Carers completed questionnaires for 485 care‐recipients, 267 of whom were examined (completion rate = 55.1%). The prevalence of decay (D > 0) was 16.9% and 76.3% had caries experience (DMFT > 0). In unadjusted analysis, care‐recipients at institutions had a significantly higher mean DMFT than other settings. After adjusting for carer and care‐recipient characteristics, there was no difference in any of the DMFT components among residential settings. However, there were statistically significant associations (OR ± 95% CI excluding unity) between decayed teeth and moderate and high intake of sweet drinks and frequency of dental visits. Higher odds of missing teeth were associated with type of disability, general anaesthetic requirement for dental treatment and low and high carer‐contact. Higher odds of filled teeth were associated with age, no oral hygiene assistance (OHA) and high carer‐contact. Higher odds of caries experience were associated with age and no OHA. Conclusions: Residential setting was not associated with caries experience. Modifiable risk factors were diet, frequency of dental visits, no OHA and carer‐contact hours.  相似文献   
994.
995.
In a search for an alternative route of production of the important therapeutic radionuclide (192)Ir (T(1/2)=78.83 d), the excitation function of the reaction (192)Os(p,n)(192)Ir was investigated from its threshold up to 20 MeV. Thin samples of enriched (192)Os were obtained by electrodeposition on Ni, and the conventional stacked-foil technique was used for cross section measurements. The experimental data were compared with the results of theoretical calculations using the codes EMPIRE-II and ALICE-IPPE. Good agreement was found with EMPIRE-II, but slightly less with the ALICE-IPPE calculations. The theoretical thick target yield of (192)Ir over the energy range E(p)=16-->8 MeV amounts to only 0.16MBq/muA.h. A comparison of the reactor and cyclotron production methods is given. In terms of yield and radionuclidic purity of (192)Ir the reactor method appears to be superior; the only advantage of the cyclotron method could be the higher specific activity of the product.  相似文献   
996.
997.
Gene expression profiles provide an opportunity to dissect the heterogeneity of solid tumors, including colon cancer, to improve prognosis and predict response to therapies. Bayesian binary regression methods were used to generate a signature of disease recurrence in patients with resected early stage colon cancer validated in an independent cohort. A 50-gene signature was developed that effectively distinguished early stage colon cancer patients with a low or high risk of disease recurrence. RT-PCR analysis of the 50-gene signature validated 9 of the top 10 differentially expressed genes. When applied to two independent validation cohorts of 55 and 73 patients, the 50-gene model accurately predicted recurrence. Standard Kaplan–Meier survival analysis confirmed the prognostic accuracy (P < 0.01, log rank), as did multivariate Cox proportional hazard models. We tested potential targeted therapeutic options for patients at high risk for disease recurrence and found a clinically important relationship between sensitivity to celecoxib, LY-294002 (PI3kinase inhibitor), retinol, and sulindac in colon cancer cell lines expressing the poor prognostic phenotype (P < 0.01, t test), which performed better than standard chemotherapy (5-FU and oxaliplatin). We present a genomic strategy in early stage colon cancer to identify patients at highest risk of recurrence. An ability to move beyond current staging by refining the estimation of prognosis in early stage colon cancer also has implications for individualized therapy.  相似文献   
998.
999.
The radioprotective effect of bael (Aegle marmelos, AME) extract was studied in Swiss albino mice against radiation-induced changes in the peripheral blood, spleen colony forming units, and intestinal mucosa. The mice were treated with 250 mg/kg body weight of AME orally once daily for five consecutive days before exposure to an acute dose of 7 Gy of gamma radiation after the last administration. The peripheral blood was collected and evaluated for red blood cell (RBC), hemoglobin, total leukocyte count (TLC), and lymphocyte count on days one and seven postirradiation. The nucleated bone marrow cells were isolated and tested for colony-forming units (CFUs) in spleen at days one and seven. AME protected mice against the radiation-induced decline in hemoglobin, total leukocyte, and lymphocytes counts and the clonogenicity of hemopoietic progenitor cells assessed by the exogenous spleen colony-forming assay. Irradiation of mice caused a significant decline in the villus height and crypt number with an increase in goblet and dead cells in the small intestine, where the maximum changes were observed on day one postirradiation, indicating a severe damage, and signs of recovery at day seven postirradiation. Treatment of mice with AME before irradiation elevated the peripheral cell count as well as villus height and the crypt number accompanied by a decline in goblet and dead cells when compared with the irradiation control. The recovery and regeneration were faster in AME pretreated animals than the irradiation alone. AME pretreatment significantly decreased lipid peroxidation accompanied by a significant elevation in the GSH concentration in the mouse intestine. The data clearly indicate that the AME significantly reduced the deleterious effect of radiation in the intestine and bone marrow of mouse and could be a useful agent in reducing the side effects of therapeutic radiation.  相似文献   
1000.
Aim To find the relationship of periodontal status and dental caries status with oral health knowledge, attitude, behavior, among professional students in India.
Methodology In a cross sectional study, a total of 825 students (males: 577, females: 248) fi'om six professions were surveyed using a self administered structured questionnaire including 41 multiple choice questions and the WHO Oral Health Assessment Form (1997). The data was analyzed using the SPSS version 13.0 to perform the Student's t-test, ANOVA test, Scheffe's test and Chi-square test, linear regression analysis.
Results The mean percentage scores of the students for knowledge were 53.25 ±15.05; for attitude 74.97±20.48; and for behavior 59.09 ±18.77. The percentage of students with calculus score was found to be significantly high (43.8%). The percentage of professional students with DMFT〉4 was 14.1% and the percentage of students with decayed teeth was 46.2%. The regression analysis showed that the oral health behavior of the students was dependent on the attitude (P〈0.001), but showed no significant linear relation with the knowledge. Also, that the mean DMFT score was dependent on the oral health behavior (P〈0.05), but showed no significant relationship with the knowledge and attitude of the students. The periodontal status was independent on the knowledge, but showed a significant relationship with attitude and behavior of the students.
Conclusion A positive attitude and adherence to good oral hygiene behaviors is associated with better oral health.  相似文献   
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