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41.
To describe the association between coding and classification practices and observed stage-specific incidence and survival trends in Norway over time.We identified all women diagnosed with invasive breast cancer in the period between 1980 and 2015. Changes in the coding and classification of breast cancer in the study period were described, and stage-specific incidence rates and relative survival were calculated.A total of 90 362 women were diagnosed with primary breast cancer, stage I–IV, or unknown stage, in the study period. Stage-specific incidence was significantly influenced by changes in coding practice, classification systems and the implementation of the screening program. These changes have mostly affected the proportion of stage I and “unknown”, but also stages II, III and IV. The proportion of stage I showed a clear increase during the implementation period of the national screening program, and was most pronounced within the age group 50–69. Stage-specific trends for relative survival were less influenced by changes in coding and classification of stage.Our study showed that the stage-specific incidence trends in Norway were influenced by changes in the coding and classification practice. These findings should be taken into consideration in future research and evaluation related to stage-specific trends and stage migration of breast cancer in Norway.  相似文献   
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目的:考察苦黄缓释微丸的制备及其质量指标。方法:利用流化床包衣设备,采用薄膜包衣法制备苦黄缓释微丸,以总蒽醌为指标性成分,测定缓释微丸的释放度,并考察了包衣处方工艺因素对药物释放的影响。结果:流化床薄膜包衣法成功制备了苦黄缓释微丸,其Eudragit RS 30D与Eudragit RL 30D的用量比例为1∶0时,包衣增重为14%;累积释放百分率2h26%,6h70%,12h90%。结论:水性薄膜包衣技术制备苦黄缓释微丸,具有良好的体外缓释行为。  相似文献   
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Previous functional neuroimaging studies in Parkinson's disease (PD) patients with impulse control disorders (ICDs) demonstrated dysfunction of the reward network, although the extent of anatomical changes is unclear. The aim of this study was to measure brain cortical thickness and subcortical volumes, and to assess their relationship with presence and severity of symptoms, in PD patients with and without ICDs. We studied 110 PD patients (N = 58 with ICDs) and 33 healthy controls (all negative for ICDs) who underwent an extensive neurological, neuropsychological, and behavioral assessment as well as structural 1.5 Tesla magnetic resonance imaging (MRI). Between‐group differences in brain cortical thickness and subcortical volumes, assessed with the FreeSurfer 5.1 tool, were analyzed. In patients with ICDs, we found significant cortical thinning in fronto‐striatal circuitry, specifically in the right superior orbitofrontal, left rostral middle frontal, bilateral caudal middle frontal region, and corpus callosum, as well as volume reduction in the right accumbens and increase in the left amygdala. Finally, we observed a positive association relationship between severity of impulsive symptoms and left rostral middle frontal, inferior parietal, and supramarginal areas. These results support the involvement of both reward and response inhibition networks in PD patients with ICDs. Moreover, their severity is associated with alterations in brain regions linked with reward and top‐down control networks. Increased understanding of the mechanisms underlying impulsive and compulsive behaviors might help improve therapeutic strategies for these important disorders. © 2015 International Parkinson and Movement Disorder Society  相似文献   
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Statement of problem

The effect of screw-access holes and mechanical cycling on fracture resistance of 3-unit screw-retained zirconia-based implant-supported fixed dental prostheses (ISFDPs) is unknown.

Purpose

The purpose of this in vitro study was to evaluate the effect of screw-access holes on the maximum fracture load (Lf) of 3-unit ISFDPs fabricated with the same abutment design for screw (s)-retained and cement (c)-retained with either a metal- or zirconia-based framework, testing the hypotheses that ISFDPs with screw-access holes have the lowest Lf and that mechanical cycling decreases the Lf of screw-retained ISFDPs.

Material and methods

Models with fiberglass bases with 2 implants were fabricated. Special abutments were designed to allow for both s- and c-retained ISFDPs. The study considered the type of framework (s-retained metal-based and s-retained zirconia-based), fixation (s and c), and aging (a) with mechanical cycling, resulting in the following experimental groups (n=12): c-retained metal-based ISFDP; s-retained metal-based ISFDP (Ms); s-retained zirconia-based ISFDP aged by mechanical cycling (Zsa); and s-retained metal-based ISFDP aged by mechanical cycling (Msa). All ISFDPs were porcelain veneered and subjected to compressive load to failure. Fracture load data were statistically analyzed using 1-way ANOVA and Tukey range tests (α=.05). Fractography was used to evaluate the fracture surfaces.

Results

Cement-retained ISFDP (Zc and Mc) showed the greatest Lf values (P<.001). Zs prostheses showed higher Lf values than those for Ms. Aging significantly decreased the Lf of Zsa but had no effect on Msa. Chipping was the failure mode most frequently found. Only Zs and Zsa ISFDPs showed catastrophic failures.

Conclusions

ISFDPs with screw-access holes showed lower Lf values, regardless of the framework type. Mechanical cycling affected the Lf of screw-retained zirconia-based ISFDPs.  相似文献   
48.
聂黎行  张烨  戴忠  张毅  马双成 《中国中药杂志》2015,40(16):3245-3248
化学药品的晶型研究十分广泛,但中药中活性化学成分的多晶型现象尚未引起足够重视。该文以无水的脱水穿心莲内酯和含水的升麻素苷为代表,采用显微、熔点、差热分析和红外光谱技术探讨了不同晶型中药化学对照品的差异。结果表明晶型不同会引起熔点、热行为和红外光谱的改变。提示在应用中药化学对照品时如得到不同的指标测定结果,须考虑多晶型的存在。不同晶型的中药活性成分的化学性质差异尚待深入研究。  相似文献   
49.

Background

Gallstones and alcohol are currently the most frequent aetiologies of acute pancreatitis (AP). The aim of this study is to quantify these aetiologies worldwide, by geographic region and by diagnostic method.

Methods

A systematic review of observational studies published from January 2006 to October 2017 was performed. The studies provided objective criteria for establishing the diagnosis and aetiology of AP for at least biliary and alcoholic causes. A random-effects meta-analysis was used to assess the frequency of biliary (ABP), alcoholic (AAP) and idiopathic AP (IAP) worldwide and to perform 6 subgroup analyses: 2 compared diagnostic methods for AP aetiology and the other 4 compared geographic regions.

Results

Forty-six studies representing 2,341,007 patients of AP in 36 countries were included. The global estimate of proportion (95% CI) of aetiologies was 42 (39–44)% for ABP, 21 (17–25)% for AAP and 18 (15–22)% for IAP. In studies that used discharge code diagnoses and in those from the US, IAP was the most frequent aetiology. ABP was more frequent in Latin America than in other regions.

Conclusion

Gallstones represent the main aetiology of AP globally, and this aetiology is twice as frequent as the second most common aetiology.  相似文献   
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