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101.
本文依据一组含有不同比例待测和干扰组分的标准混合液的吸收值,采用一元线性回归方法,在选择最佳测定波长对的同时建立标准工作曲线方程,使其更符合实际作品测定时的情况,提高了结果的精度和可靠性,并使计算量和实验工作量得以降低。应用于复方氨基比林注射液中三组分氨基比林、安替比林和巴比妥的同时测定,其平均回收率分别为99.8%,100.4%和99.8%,变异系数分别为0.59,1.48和1.05,结果优于卡尔曼滤波法、偏最小二乘法和目标因子分析法。  相似文献   
102.
Recurrent falls are a disabling feature of Parkinson's disease (PD). We have estimated the incidence of falling over a prospective 3 month follow-up from a large sample size, identified predictors for falling for PD patients repeated this analysis for patients without prior falls, and examined the risk of falling with increasing disease severity. We pooled six prospective studies of falling in PD (n = 473), and examined the predictive power of variables that were common to most studies. The 3-month fall rate was 46% (95% confidence interval: 38-54%). Interestingly, even among subjects without prior falls, this fall rate was 21% (12-35%). The best predictor of falling was two or more falls in the previous year (sensitivity 68%; specificity 81%). The risk of falling rose as UPDRS increased, to about a 60% chance of falling for UPDRS values 25 to 35, but remained at this level thereafter with a tendency to taper off towards later disease stages. These results confirm the high frequency of falling in PD, as almost 50% of patients fell during a short period of only 3 months. The strongest predictor of falling was prior falls in the preceding year, but even subjects without any prior falls had a considerable risk of sustaining future falls. Disease severity was not a good predictor of falls, possibly due to the complex U-shaped relation with falls. Early identification of the very first fall therefore remains difficult, and new prediction methods must be developed.  相似文献   
103.
In order to establish the reliability of the assessment of tumour stage and hence of resectability of carcinoma of the pancreatic head by ultrasonography (US) and computed tomography (CT) a retrospective analysis was performed on 41 patients. Both direct imaging techniques were very accurate in detecting non-resectable disease, 100 and 85% respectively, but were much less accurate in predicting resectable cancer, 18 and 15% respectively. False-resectable results were established in 58% of US examinations and 42% of CT examinations. As demonstrated in this study, predicting resectability of carcinoma of the pancreatic head with US and CT is an inadequate method of assessing tumour stage and should be complemented by other techniques to ensure a reliable result.  相似文献   
104.
OBJECTIVES: We investigated the relation between parental tobacco use and malnutrition in children <5 y of age and compared expenditures on foods in households with and without tobacco use. METHODS: Tobacco use, child anthropometry, and other factors were examined in a stratified, multistage cluster sample of 77 678 households from the Bangladesh Nutrition Surveillance Project (2005-2006). Main outcome measurements were stunting, underweight, and wasting, and severe stunting, severe underweight, and severe wasting. Secondary outcomes included the proportion of household expenditures spent on food. RESULTS: The prevalence of parental tobacco use was 69.9%. Using the new World Health Organization child growth standards, prevalences of stunting, underweight, and wasting were 46.0%, 37.6%, and 12.3%, respectively. After adjusting for potential confounders, parental tobacco use was associated with an increased risk of stunting (odds ratio [OR] 1.17, 95% confidence interval [CI] 1.12-1.21, P < 0.0001), underweight (OR 1.17, 95% CI 1.12-1.22, P < 0.0001), and wasting (OR 1.10, 95% CI 1.03-1.17, P = 0.004), and severe stunting (OR 1.16, 95% CI 1.10-1.23, P < 0.0001), severe underweight (OR 1.21, 95% CI 1.13-1.30, P < 0.0001), and severe wasting (OR 1.14, 95% CI 0.98-1.32, P = 0.09). Households with tobacco use spent proportionately less per capita on food items and other necessities. CONCLUSIONS: In Bangladesh parental tobacco use may exacerbate child malnutrition and divert household funds away from food and other necessities. Further studies with a stronger analytic approach are needed. These results suggest that tobacco control should be part of public health strategies aimed at decreasing child malnutrition in developing countries.  相似文献   
105.
In recent years, 5 genes have been identified that are unambiguously associated with genetic forms of Parkinson's disease. These genes probably explain less than 10% of all cases of Parkinson's disease. Clinically, these genetic forms can closely resemble idiopathic Parkinson's disease. Mutation analysis could be considered in cases involving an age at onset before 45 years, a positive family history or atypical presentations. However, the role of genetic testing in clinical practice remains to be established. Dysfunction of the ubiquitin-proteasome complex, abnormalities of the oxidative stress response and mitochondrial defects represent the three main disease mechanisms implicated in Parkinson's disease caused by these gene mutations. Further research is likely to contribute to the understanding and future treatment of idiopathic Parkinson's disease.  相似文献   
106.
Gait disorders are seen frequently and often have a neurological cause. The clinical management of patients presenting with a gait disorder is often complicated due to the large number of diseases that can cause a gait disorder and to the difficulties in interpreting a specific gait disorder properly. In addition, the currently available classification systems are confusing. Gait disorders can be classified into the following categories: antalgic, paretic-hypotonic, spastic, vestibular, ataxic, hypokinetic-rigid, cautious, or functional. A correct interpretation of the gait disorder is important as this determines the diseases to be considered, the auxilliary investigations that have to be carried out, and the selection of rational therapeutic options.  相似文献   
107.
An 80-year-old man was admitted because of head trauma following a fall down a staircase. Initial CT-imaging of the brain showed only global atrophy, but repeated CT-imaging 4 days later revealed a subdural hygroma. Because of the discrepancy between the radiological deterioration and the unchanged neurological condition, we refrained from neurosurgical evacuation. Two months after the trauma, the subdural hygroma had been spontaneously resorbed, but neurological examination revealed severe residual neurological abnormalities. Subdural hygroma is a little known complication in the acute stage ofhead trauma, which is seen mainly in elderly patients. The pathophysiology is not well known. Differentiating subdural hygroma (cerebrospinal fluid (CSF) accumulation in the subdural space) from external hydrocephalus (excessive CSF accumulation in the subarachnoid space) is important in view of the therapeutic consequences. Because CT-imaging usually cannot differentiate between these 2 conditions, we recommend the use of MRI.  相似文献   
108.
109.
A 19-year-old, untransfused Melanesian man from Papua New Guinea was admitted to the hospital for repair of an atrial septal defect. His serum contained an alloantibody that reacted strongly on the indirect antiglobulin test and was identified as anti-Ge. Gerbich-negative blood was transfused following urgent surgery. A 51Cr red cell survival study performed 2 weeks after surgery yielded zero survival of Gerbich-positive cells after 24 hours. A monocyte-driven, antibody-dependent, cell-mediated cytotoxicity assay performed on both pretransfusion and posttransfusion serum samples and on concentrated serum showed less than 1 percent specific lysis of Gerbich-positive cells. This did not correlate with the indication of clinical significance predicted by the 51Cr study. Red cell adherence and phagocytosis, not evident in a monocyte monolayer assay using native serum, were demonstrable in 16 percent of monocytes by the use of concentrated serum.  相似文献   
110.
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