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51.
Vitamin D (Vit D) is an essential element for the regulation of serum calcium, phosphate, and alkaline phosphatase (Alk Ph). Because the Vit D serum level is not usually measured directly, Vit D deficiency is diagnosed indirectly by changes in serum calcium, phosphate, and Alk Ph leves. The current study assessed the status of these biochemical parameters in subjects with different degrees of Vit D deficiency. We selected 1210 subjects, between 20 and 69 years old, randomly from the Tehran population. Subjects with diseases or medications that modified bone metabolism were excluded from the study. Serum 25(OH) D, calcium, phosphate, Alk Ph, and parathyroid hormone (PTH) levels were measured and the status of these biochemical parameters was compared in subjects with different degrees of Vit D deficiency. Vit D deficiency was diagnosed in 79.6% of the subjects. Different degrees of Vit D deficiency were classified as follows: group 1, severe; group 2, moderate; and group 3, mild. Serum PTH levels in the Vit D-deficient groups were significantly higher than that in group 4 (normal Vit D). Serum calcium and phosphate levels in groups 1 and 2 were significantly lower than those in groups 3 and 4. No significant difference was seen in serum Alk Ph in the groups with different degrees of Vit D deficiency. The sensivity for at least one biochemical variable (calcium, phosphorus, or Alk Ph) for the detection of severe, moderate, and mild Vit D deficiency was 24.2%, 13.8%, and 6%, respectively. When the serum 25(OH) D level was reduced to less than 25 nmol/l (groups 1 and 2), the effects of Vit D deficiency on calcium and phosphate levels were obvious. Therefore, the usual biochemical parameters (calcium, phosphate, Alk Ph) alone do not have sufficient sensitivity to detect mild deficiency of Vit D.  相似文献   
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Approximately one-third of patients with type 1 diabetes develop a variety of complications as a result of mechanisms that are not completely understood. However, insufficient metabolic control seems to play a major role. Other factors such as magnesium (Mg) could also be of importance. We designed this study to elucidate the effect of oral magnesium administration on plasma lipid profile and mesenteric fat in male Wistar rats. Animals were divided into 4 groups (n = 10 in each group): one group served as control, while the other groups were made diabetic with a single i.v. injection of 40 mg/kg streptozocin. Animals in which the diabetic state lasted for 10 days were referred as acute diabetic rats, whereas those in which the diabetes lasted for 8 weeks were defined as chronic diabetics. Mg-treated chronic diabetic received 10 g/l of MgSO4 added to the drinking water (0.46 g/24 h) for eight weeks following which the left common carotid artery was cannulated for continuous recording of blood pressure. Blood glucose, magnesium and lipid profiles levels were also determined. Diabetes induction caused plasma glucose, high density lipoprotein (HDL), low density lipoprotein (LDL), very low density lipoprotein (VLDL), total cholesterol and triglyceride concentrations to increase, however plasma Mg level was decreased. Administration of MgSO4 for eight weeks caused the return of the above factors to their normal levels. Mg concentrations also increased but failed to reach normal levels. Diabetes induction caused mesenteric fat/body weight ratio to increase, but administration of MgSO4 reduced the ratio to normal levels. In addition, Mg administration returned systolic blood pressure to the normal level. Our results support the hypothesis that Mg may play a part in the management of diabetes and the prevention of its vascular complications in streptozocin-induced diabetic rats and it may be useful in the treatment of hyperlipidaemia in diabetic case.  相似文献   
53.
Ertapenem is a new carbapenem with a broad spectrum of activity and an extended half-life, permitting once daily administration. Although high-performance liquid chromatography (HPLC) methods have been described for ertapenem, these are complex and involve column switching and thus this type of assay may not suitable for use in routine clinical microbiology laboratories. In this study we report a rapid, straightforward HPLC method for the detection of ertapenem in human serum.  相似文献   
54.
The major aim of this study was to model the effect of two causal factors, i.e. coating weight gain and amount of pectin-chitosan in the coating solution on the in vitro release profile of theophylline for bimodal drug delivery. Artificial neural network (ANN) as a multilayer perceptron feedforward network was incorporated for developing a predictive model of the formulations. Five different training algorithms belonging to three classes: gradient descent, quasi-Newton (Levenberg-Marquardt, LM) and genetic algorithm (GA) were used to train ANN containing a single hidden layer of four nodes. The next objective of the current study was to compare the performance of aforementioned algorithms with regard to predicting ability. The ANNs were trained with those algorithms using the available experimental data as the training set. The divergence of the RMSE between the output and target values of test set was monitored and used as a criterion to stop training. Two versions of gradient descent backpropagation algorithms, i.e. incremental backpropagation (IBP) and batch backpropagation (BBP) outperformed the others. No significant differences were found between the predictive abilities of IBP and BBP, although, the convergence speed of BBP is three- to four-fold higher than IBP. Although, both gradient descent backpropagation and LM methodologies gave comparable results for the data modeling, training of ANNs with genetic algorithm was erratic. The precision of predictive ability was measured for each training algorithm and their performances were in the order of: IBP, BBP>LM>QP (quick propagation)>GA. According to BBP-ANN implementation, an increase in coating levels and a decrease in the amount of pectin-chitosan generally retarded the drug release. Moreover, the latter causal factor namely the amount of pectin-chitosan played slightly more dominant role in determination of the dissolution profiles.  相似文献   
55.
The aim was to develop and validate an addictive behaviors screening tool in school children. METHODOLOGY: A cross sectional study including a self administrated 223 item questionnaire developed in Arabic language. The questionnaire included identification of the student and seven life domains: school, family, addiction, relationships with peers, leisure and well being, risky behaviors and personality traits. N=854 high school children. of Monastir City. RESULTS: the questionnaire Alpha Cronbach's Coefficient ranged between 0.3 and 0.8. Only items with a coefficient higher than 0.6 were maintained in the final version. The time reliability by using the Bland and Altman method 15 days after the first measure showed a Pearson's coefficient of 0.81. Validity evaluated by principal components analysis led to 3 independent factors consisting respectively in 20, 4 and 3 well correlated items: family, school and risky behaviors. CONCLUSION: validated version of the questionnaire consisted in 102 items, easy to read and understand. This version doesn't require much time to be filled in and takes into consideration cultural particularities of the school children of Monastir. It could be considered as an interesting tool for both the assessment and the prevention of addictive behaviors in school.  相似文献   
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This study was conducted to establish clinicians’ perspectives of a set of radiology curriculum topics for medical student teaching, which were held to be important by radiologists. A questionnaire was sent to clinicians in all specialties. Forty‐six clinicians (51.1%) out of 90 returned the questionnaires. All curriculum topics were scored above an average of 4 (agree). The five highest ranking curriculum topics in order of importance were: developing a system for viewing chest radiographs (5.59), developing a system for viewing abdominal radiographs (5.56), developing a system for viewing bone and joint radiographs (5.33), distinguishing normal structures from abnormal in chest and abdominal radiographs (5.33) and identifying gross bone or joint abnormalities in skeletal radiographs (5.22). Correlative analysis between speciality groups showed surgical and medical specialities were significantly different in their responses of two learning outcomes: basic knowledge about the contrast media benefits and risks (P= 0.01) and ability to select the most appropriate and the most cost‐effective methods of radiological investigations for clinical situations (P= 0.03). Acute specialities were not significantly different from the other two groups for these two learning outcomes. There was no statistically significant difference for other learning outcomes between the three speciality groups.  相似文献   
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