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Digital X-ray radiogrammetry (DXR) calculates peripheral bone mineral density (BMD) from hand radiographs. The aim of this study was to examine in vitro and in vivo precision for the new direct digital version of DXR, a development of the conventional DXR. The in vitro precision for direct DXR was tested on 4 different X-ray equipments, based on 31 radiographs of the same phantom. The in vivo precision was based on duplicate hand radiographs from both hands in 39 individuals. For the 4 X-ray equipments, in vitro precision ranged from 0.14% to 0.30%, expressed as coefficient of variations (CV%) and from 0.0012 to 0.0028 g/cm2, expressed as smallest detectable difference (SDD). The precision was correlated to the resolution of the radiographic equipment (r = 0.95, p = 0.05). The corresponding values for the in vivo precision for mean values of both hands were: CV% = 0.46%; SDD = 0.0046 g/cm2, and least significant change (LSC%) = 1.28%. The DXR-BMD for 1 of the X-ray equipments differed 1.1% from the overall mean. The precision for direct DXR was highly satisfactory both in vitro and in vivo. DXR-BMD values may differ between the radiographic equipments, and follow-up measurements should be performed with the same X-ray equipment.  相似文献   
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OBJECTIVE: To compare levels of health-related quality of life (HRQOL) among patients with rheumatoid arthritis (RA) to those of the general population. METHODS: Disease burden was assessed using a generic health status instrument (Medical Outcome Study Short Form-36) for measurements of HRQOL and SF-6D to calculate utility scores in representative patients aged 20 to 79 years from the Oslo RA Register (n = 1052), and in individuals in the general population (n = 2323). Comparisons were performed with respect to sex and age, and standardized difference scores (s-scores) were calculated for comparisons with the norm. RESULTS: HRQOL in patients with RA was reduced compared to the general population on all scales of the SF-36 for both males and females and for all age groups. s-scores adjusted for age and education ranged from -1.39 for physical functioning to -0.27 for mental health. The overall difference in utility was 0.16 and ranged from 0.13 (in female patients below 50 yrs) to 0.20 (patients 50-60 years). This implies that RA of 1 year duration entails a disease burden of 14-20 quality-adjusted life-years in 100 RA patients. CONCLUSION: RA inflicts a substantial disease burden, and the disease affects all HRQOL dimensions as measured by the SF-36 in both sexes and in all age groups. Physical functioning is predominantly affected, but RA has social and mental consequences.  相似文献   
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BACKGROUND: Eosinophilic oesophagitis may be increasing but the prevalence in the general population remains unknown. Our aim was to assess this and the presence of eosinophils in the distal oesophageal epithelium in the community. METHODS: Oesophagogastroduodenoscopy was performed in a random sample (n = 1000) of the adult Swedish population (mean age 54 years, 49% men). Oesophageal biopsy samples were obtained from 2 cm above, and at, the Z-line. Any eosinophil infiltration of the epithelium was defined as "eosinophils present". Definite eosinophilic oesophagitis was defined as > or =20, probable as 15-19, and possible as 5-14 eosinophils/high-power field (HPF, at magnification x 40) in oesophageal biopsy specimens. RESULTS: Eosinophils were present in 48 subjects (4.8%, 95% CI 3.5 to 6.1%, mean age 54 years, 63% men), in 54% without troublesome reflux symptoms. Definite eosinophilic oesophagitis was present in four subjects (0.4%, 95% CI 0.01 to 0.8%, mean age 51 years, 75% men) and probable eosinophilic oesophagitis in seven subjects (0.7%, 95% CI 0.2 to 1.2%, mean age 58 years, 43% men). Erosive oesophagitis (OR = 2.99, 95% CI 1.58 to 5.66) and absence of dyspepsia (OR = 0.23, 95% CI 0.07 to 0.75) and Helicobacter pylori infection (OR = 0.41, 95% CI 0.19 to 0.92) were independent predictors for "eosinophils present". Definite eosinophilic oesophagitis was associated with dysphagia (2/66 vs 2/926, p = 0.025), and probable eosinophilic oesophagitis with narrowing of the oesophageal lumen (2/15 vs 5/978, p = 0.005). CONCLUSIONS: Oesophageal eosinophils were present in nearly 5% of the general population; approximately 1% had definite or probable eosinophilic oesophagitis. Oesophageal eosinophils may be a manifestation of reflux disease in adults, but the condition is as likely to be asymptomatic and go unrecognised.  相似文献   
107.
This correlational study explored the Resilience Scale for Adolescents (READ) as a predictor for developing depressive symptoms controlling for known risk factors. A young adolescent sample (N = 387) completed the READ, the Short Mood and Feeling Questionnaire (SMFQ), Social Phobia Anxiety Index for Children (SPAI-C), and the occurrence of Stressful Life Events (SLE). In addition, a subsample of their parents (N = 240) completed a parental version of READ (READ-P). The results indicated that the READ assesses important protective factors that are associated with fewer depressive symptoms among young adolescents even when controlling for known risk factors. All five READ-factors were predictors of depressive symptoms, while the READ-P showed no predictive value. There were no significant interaction effects between READ and SLE. There were, however, significant main-effects supporting a compensatory model of protective factors. The findings suggest that the READ is a significant predictor of mental health and a useful tool for further research examining differences in stress tolerance among young adolescents.  相似文献   
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Objective

To test whether young physicians improve their communication skills between graduating from medical school and completing clinical internship, and to explore contributing background and/or internship factors.

Methods

Norwegian medical students graduating June 2004 were invited to take part in a videotaped standardized patient interview February 2004. Of the 111 students who originally participated, 62 completed a second interview February 2006. Observed communication skills were assessed with the Arizona Communication Interview Rating Scale (ACIR).

Results

The level of communication skills increased significantly during the period for participants overall; and for females but not males. General social skills reached significantly higher levels than specific professional skills, both types of skill improving during the study. Independent predictors were working in local hospitals, learning atmosphere and low stress.At school completion, 50% reached a level defined as ‘advanced beginner’. Towards the end of the internship, 58% reached ‘capable’ and 27% ‘competent’ levels of communication skills.

Conclusions

Female physicians improved most in communication skills, the gender difference being multivariate mediated through low stress levels and learning atmosphere. The findings support the division of communication skills into general social and specific professional skills.

Practice implications

The relatively low proportion of young physicians, especially males, developing the capability to practise independently at internship completion indicates a need for more effective training in communication skills, during both medical school and internship.  相似文献   
110.

Objective

Multiple lines of evidence suggest that sex hormones may play a role in the pathogenesis or clinical expression of rheumatoid arthritis (RA). Studies on the effects of exogenous estrogens in RA patients have yielded contradictory results. We undertook this study to determine the effects of the selective estrogen receptor α (ERα) agonist Org 37663 in patients with RA, in terms of both its estrogenic effects and its ability to ameliorate disease activity.

Methods

A 10‐week, multicenter, randomized, double‐blind, placebo‐controlled, parallel group, dose‐finding, proof‐of‐concept trial was initiated to obtain data on the efficacy and safety of Org 37663 in postmenopausal female patients with RA who were receiving background treatment with either methotrexate or sulfasalazine. Patients were randomized to receive placebo or Org 37663 at doses of 4 mg/day, 15 mg/day, or 50 mg/week. The primary efficacy variable was the Disease Activity Score in 28 joints (DAS28).

Results

Org 37663 induced a clear biologic, estrogenic response in several organ systems, including a dose‐related increase in levels of sex hormone binding globulin. However, the DAS28 decreased similarly for all treatment groups including placebo, indicating lack of clinical efficacy of Org 37663 in this trial.

Conclusion

The observed lack of clinical benefit in RA patients treated with an ERα agonist, in association with a clear biologic response to the study drug, provides evidence that a biologically relevant ERα‐mediated estrogenic effect is not associated with a clinically relevant effect on RA symptoms and signs.
  相似文献   
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