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71.
We have previously shown that patients with renal fibromuscular dysplasia (FMD) have asymptomatic carotid lesions and that familial forms may occur. The objective of this study was to test whether carotid lesions could be detected in relatives of familial cases. High-resolution echotracking of the carotid artery was performed in 47 relatives of 13 cases from six families. This non-invasive investigation led to a semiquantitative arterial score that was compared with that obtained for 47 controls matched for age and sex and that for 125 sporadic cases. Familial resemblance was tested by using a generalized estimating equation approach taking into account the clustering of scores in families. As expected, FMD cases had a significantly higher score than controls (4.02 vs 2.52, P<10(-5)). Familial cases were not significantly different from sporadic cases. Of interest, the 47 apparently healthy relatives of familial cases had also a high carotid score (4.17), very significantly higher than that of controls (2.52, P<10(-5)) even though lower than the corresponding index FMD cases (4.81, P=0.01). Segregation analysis showed that 52% of the descendants of subjects with a score >4 had a score >4, a proportion consistent with autosomal-dominant transmission of the trait. Altogether these results strengthen the hypothesis of renal FMD being a systemic arterial disease and argue for a familial resemblance that may be due to a major genetic effect. The carotid score obtained by high-resolution echotracking may provide a non-invasive surrogate marker for renal FMD of potential value for use in linkage strategies on large pedigrees.  相似文献   
72.
Goiter rate, serum TSH, antithyroperoxidase (TPOAb), antithyroglobulin (TgAb) antibodies, and urinary iodine concentration (UIC) were evaluated 10-11 yr prior (1983-1984) and 5-6 yr after (1999-2000) national salt iodization in Iran. Pre- and post-iodization groups consisted of 465 and 1426 adults aged > or =20 yr, respectively, selected by random cluster sampling in Tehran province. Total, grade 1 and grade 2 goiter rates were 65.2, 53.1, and 12.1% in 1983-1984 vs 25.2, 15.5, and 9.7% in 1999-2000 (p<0.0001). Median serum TSH was 1.5 mIU/l in 1983-1984 vs 0.8 mIU/l in 1999-2000 (p<0.0001). Median TSH also decreased in 20-29, 30-39, 40-49, 50-59, and > or =60- yr-adults in 1983-1984 vs 1999-2000 (p<0.0001). In 1983-1984, positive TPOAb and positive TgAb were detected in 3.2 and 4%, respectively, using agglutination test. Corresponding values were 12.5 and 16.8% using immunoenzymometric assay in 1999-2000. Overt and subclinical hypothyroidism was present in 0 and 32.8/1000 in 1983-1984 vs 3.5 and 21.7/1000 in 1999-2000, respectively. Overt and subclinical hyperthyroidism was detected in 4.4 and 4.4/1000 in 1983-1984 vs 0.7 and 5.6/1000 in 1999-2000, respectively. Subclinical hypothyroidism in males was significantly more frequent in 1983-1984 vs 1999-2000 (odds ratio 5.02, 95% confidence interval 1.72-14.68; p=0.004). Salt iodization resulted in adequate UIC, decrease in serum TSH and subclinical hypothyroidism in males, and an increase in thyroid autoantibodies without significant change in thyroid abnormalities. Benefits of iodine supplementation far outweigh its hazards in Tehranian adults.  相似文献   
73.
74.
BACKGROUND AND PURPOSE: A common isolated reported finding in brain imaging studies on developmentally delayed children is delayed myelination. We hypothesized that brain MR imaging scans of these children would show delayed subcortical myelination of white matter with specific involvement of the subcortical U-fibers as these represent terminal zones of myelination and are the last areas to myelinate. MATERIALS AND METHODS: A total of 93 children (31 controls, 62 with idiopathic developmental delay [IDD]) aged 17 to 46 months were identified on the basis of having brain MR imaging for evaluation of IDD (cases) or for another condition (controls). Children with diseases that primarily affect white matter or overt intracranial lesions or malformations were excluded. IDD was defined as psychomotor retardation without a clear cause on the basis of history, physical, genetic, metabolic, and neuroimaging examinations. Developmental quotients (DQs) were calculated for all children with IDD on the basis of clinical history, examination, and psychometric testing. Three board-certified pediatric neuroradiologists examined axial T2-weighted brain images and used a published scoring system to rate the extent of myelination in the frontal, temporal, parietal, and peritrigonal brain regions. In addition, subcortical U-fibers in the frontal, temporal, and parietal lobes were scored separately. Data were analyzed at both the intraobserver and interobserver levels, and scores were compared between groups and tested for interactions with age and DQ. RESULTS: There were no differences in the timing or extent of myelination in the control and IDD groups at any age in any brain region. In the IDD group, there was no relationship between myelination scores and DQ or developmental domain. CONCLUSIONS: Our findings did not support the hypothesis that there is a correlation between IDD and the maturity of myelination, including the terminal zones, as seen on conventional brain MR imaging. Neuroimaging evaluation of maturity of subcortical myelination is not a marker of IDD in young children, and the isolated "finding" of delayed myelination should be interpreted with caution.  相似文献   
75.
OBJECTIVE: The abdominal and retroperitoneal lymphatic system is characterized by numerous anatomic variations. Our objective is to review MR lymphographic features of normal anatomy and abnormal conditions. CONCLUSION: MR lymphography is a noninvasive technique that is well suited for the examination of abdominal and retroperitoneal lymphatic vessels.  相似文献   
76.

Background  

Chronic kidney disease (CKD) is a global public health threat, associated with an alarming increase in morbidity and mortality. The importance is the worldwide increase in its incidence and prevalence.  相似文献   
77.
ObjectivesEvidence are available showing that higher nitric oxide production is associated with metabolic disorders. The aim of this study was to determine serum nitric oxide metabolites (NOx) concentration in subjects with metabolic syndrome (MetS).Design and methodsIn a cross-sectional study, NOx was measured in 3505 subjects, aged 20–94 years, using the Griess reaction. After excluding subjects taking medications for hypertension and dyslipidemia, data for 3148 subjects were analyzed.ResultsThere was a direct association between the numbers of metabolic risk factors and serum NOx values in both genders (p for trend < 0.05). After multivariable adjustment, serum NOx concentration was significantly higher in subjects with MetS [(31.9 (29.4–34.6) vs. 29.8 (27.6–32.1), p < 0.01) or type 2 diabetes (34.6 (31.3–38.2) vs. 30.2 (27.9–32.6), p < 0.001) as compared to their corresponding controls.ConclusionsHigher NOx concentrations in subjects with MetS and type 2 diabetes support the existing hypothesis that NO overproduction affects insulin's metabolic actions.  相似文献   
78.
Over the past few decades, microwave processing and its high potential capabilities have attracted food scientists. Application of microwave for microencapsulation is an innovative and new method in which the shell, due to having different dielectric constant, can fuse and cover core. In this research, the citric acid powder at various size ranges was microencapsulated by casein and inulin, using a domestic microwave oven. Then, for sensory evaluation purposes, they along with uncoated citric acid and commercial microcapsules were incorporated in chewing gum formulation. The qualitative and quantitative evaluations revealed the potential capability of this technique at micronized scales. Moreover, findings on some sensory characteristics showed practical and efficient applicability of inulin-coated microcapsules in chewing gum where its sensory scores were competitive and even much better than commercial ones. In addition, these observations elucidate a new approach for producing functional, nutritional and dietetic chewing gums.  相似文献   
79.
MC1R sequence variants are associated with malignant melanoma risk, and most commonly are missense mutations. Few (n=9) truncating mutations have been described in this gene as predisposing to malignant melanoma. In this study, three Jewish individuals were found to harbor an identical truncating MC1R mutation--Y152X: an Ashkenazi patient with two malignant melanomas, a non-Ashkenazi malignant melanoma patient with familial malignant melanoma and her asymptomatic mother. Both malignant melanoma patients carried additional, seemingly pathogenic MC1R variants. Haplotype analysis revealed that all three mutation carriers shared the same haplotype. This sequence variant was previously described in ethnically diverse, non-Jewish individuals and in all likelihood represents an error-prone domain that, in conjunction with other genetic and environmental factors, increases malignant melanoma risk.  相似文献   
80.
This study of 300 melanoma survivors examines the relative contributions of objective illness-related factors (stage of illness at diagnosis, time since diagnosis, and change in physical condition) and of subjective factors (cognitive appraisal) to their psychological adjustment. The findings show that lower appraisal of their situation as a threat, higher appraisal of it as a challenge, and higher appraisal of their subjective ability to cope with it all increased their well-being, while lower threat appraisal and higher appraisal of subjective ability to cope also reduced their distress. These findings, which are consistent with Lazarus and Folkman's stress coping theory, suggest that subjective factors may be more important than objective medical factors in predicting patients' adjustment. With this, more advanced stage at diagnosis contributed to reducing distress, while being married contributed both to higher well-being and reduced distress.  相似文献   
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