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81.
82.
The model of biliary tract infection induced in rats given suspension of E. coli into the bile duct is described. To prevent leakage of microorganisms after the administration, a temporary ligation of the bile duct followed. Contemporary groups of sham-operated and control rats (given saline by intrabiliary injection) were compared to assess the significance of the changes. The effect of biliary infection was concentration dependent. If 0.1 ml of the concentration containing 10(2), 10(3) and 10(6) colony-forming units/ml was injected, the mortality of rats reached 8%, 57% and 65%, respectively within 24 h. Blood and bile cultures from all dead animals grew E. coli. To evaluate the effect of chronic biliary infection, the concentration of 10(2) colony-forming units/ml was used. Serum concentrations of total and conjugated bilirubin, cholesterol and creatinine, activities of S-alanine-aminotransferase, S-aspartate-aminotransferase, alkaline phosphatase, the count of leucocytes in blood, total body weight with weight of the liver were investigated on days 1, 4 and 12 after the treatment. The results showed: an increase in leucocytes (21 +/- 4.2 10(9)/l, p less than 0.02 vs control animals) on day 4, an augmentation of serum cholesterol on day 1, (2.1 +/- 0.9 mmol/l, p less than 0.02 vs control animals), the presence of E. coli in blood on day 1 and its persistence in the bile on days 1, 4 and 12. Except the bile, all of the other symptoms were reversible by day 12.  相似文献   
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84.
Describes the development and evaluation of a pilot 12-session, school-based preventive intervention designed to enhance resilience among inner-city children who have experienced major life stress. Thirty-six 4th–6th grade children participated in the intervention in groups of 5–8 co-led by school personnel. The curriculum focussed on understanding feelings in oneself and others, perspective-taking, social problem-solving, dealing with solvable and unsolvable problems, and building self-efficacy and esteem. Pre-post evaluation showed significant improvement among participants on teacher-rated indices of learning problems and task orientation and on child ratings of perceived self-efficacy, realistic control attributions and anxiety. Program limitations and factors that restrict generalization are considered and new directions for program development and research are proposed.  相似文献   
85.
BACKGROUND. Detection and treatment for rejection after transplantation are based on the identification of myocyte damage upon endomyocardial biopsy. Noninvasive detection of such damage is possible with 111In-labeled monoclonal antimyosin antibodies (MAA). Although the presence and degree of MAA uptake parallels the rejection activity detected by biopsy, the relation between the degree of uptake and the occurrence of severe rejection-related complications has not been previously assessed. METHODS AND RESULTS. Two hundred forty-seven MAA studies were performed coinciding with biopsies in 52 patients 1-71 months after transplantation. A heart-to-lung ratio (HLR) was used as a measure of relative MAA uptake, with an HLR of 1.55 discriminating normal from abnormal studies. Of the 247 antimyosin studies, 149 coincided with absent, 38 with mild, and 60 with moderate rejection at biopsy. HLR was 1.68 +/- 0.27, 1.79 +/- 0.22, and 1.91 +/- 0.33 in the three biopsy groups, respectively (p less than 0.0001). Two hundred thirty-eight of 247 antimyosin studies coexisted with absent rejection-related complications; in nine of 247 patients, such complications were detected (five congestive heart failure episodes due to rejection and four episodes of vascular occlusion, which resulted in five deaths), and mean HLR was 1.74 +/- 0.3 and 2.1 +/- 0.16 in the two groups, respectively (p less than 0.0001). No complications were noted in 193 studies of patients with HLR of less than 2.00, whereas in nine of 45 with HRL of 2.00 or greater, complications occurred (p less than 0.0001). None of the 23 patients prospectively followed since surgery who had a gradual decrease in MAA uptake during the first 3 months showed rejection-related complications, whereas persistent uptake was associated with complications in five of nine patients (p less than 0.001). CONCLUSIONS. No rejection-related complications are seen coinciding with HLR of less than 2.00, whereas patients who have complications have an HLR of more than 2.00. The early 3-month pattern of decreasing MAA uptake is associated with a clinical course free of rejection-related complications, whereas a persistent pattern is a signal of the possibility of such complications.  相似文献   
86.
We reviewed 488 twin pregnancies that resulted in the birth of neonates weighing 1000 g or more. Complications were present in 56.7% of all pregnancies; most common were threat of premature labor (17.4%) and preeclampsia (14.5%). Perinatal mortality was 31.8 per thousand. Eighty percent of neonatal deaths in twin pregnancies involved newborns weighing less than 2000 g. Twin pregnancies are high risk pregnancies and benefit from early diagnosis, prevention and treatment of the threat of premature birth.  相似文献   
87.
A comparison was performed between technetium-99m tetrofosmin myocardial perfusion tomography at baseline and after nitrate administration, using a 2-day protocol, and rest-reinjection thallium-201 single-photon emission tomography (SPET) studies in order to assess whether nitrates enhance the detection of viable myocardium with99mTc-tetrofosmin. Fifteen patients with coronary artery disease, previous myocardial infarction and a left ventricular ejection fraction <40% underwent201T1 rest-injection and99mTc-tetrofosmin. baseline-postnitroglycerin (0.4 mg sublingually) SPET studies, within 48 h. Tomograms based on the three spatial planes were divided into 15 segments and regional tracer uptake was quantitatively analysed. Viability was defined as presence of tracer uptake >50% of peak activity on baseline studies or after reversibility. The percentage of peak activity of99mTc-tetrofosmin at baseline correlated with that of 201T1 (r=0.82,P <0.001). On baseline99mTc-tetrofosmin studies, 73 of the 225 segments that were analysed had <50% of peal. activity. Fifteen percent of these segments showed reversibility after nitrate administration, with an increase in99mTc-tetrofosmin uptake from 40%±9% to 57%±9% of peak activity (P=0.003). All reversible segments after nitrate administration had viability criteria on201Tl studies, but 20 segments that were non-viable on99mTc-tetrofosmin. studies were viable on201Tl studies. Using a threshold value of >40% of peak activity, only seven segments remained non-viable on99mTc-tetrofosmin studies. Overall agreement between99mTc-tetrofosmin with nitrates and201Tl-reinjection regarding the presence of myocardial viability was 90%. Detection of myocardial viability with99mTc-tetrofosmin. was enhanced after nitrate administration, correlating with viability criteria observed on thallium studies.  相似文献   
88.
INTRODUCTION: Colon cancer is one of the main causes of cancer death. Diagnosis requires the examination of the entire large bowel by means of radiological or endoscopic techniques. Many patients suspect of colon cancer are referred for colonoscopy but nevertheless this suspicion is not confirmed after endoscopic examination. The objective of this study is the evaluation of the reliability of abdominal ultrasound in the diagnosis of these tumors. MATERIAL AND METHOD: We selected patients suspect of colon cancer referred to the endoscopy unit for a colonoscopy. An abdominal ultrasound was carried out on all patients prior to the endoscopy. Considering the endoscopic examination as a gold standard, the sensibility, specificity, positive predictive value (PPV) and negative predictive value (NPV) of the ultrasonography were evaluated. Likewise, a series of analytical and clinical parameters were evaluated, in an attempt to establish associated factors of a colon cancer. The statistical analysis was carried out by means of the statistical package SPSS 12.0 for Windows. RESULTS: 145 patients were included in the study (56.6% males) with an average 66.72 years of age (22-89). A cancer was diagnosed in 42 cases (28.9%). In the diagnosis of colon cancer, abdominal ultrasound presents a sensitivity of 79.06%, a specificity of 92.15%, a PPV and a NPV of 80.9% and of 91.2%, respectively. Excluding from the analysis lesions of the rectal ampulla, which cannot be adequately evaluated by means of ultrasound, the figures for sensitivity, specificity, PPV and NPV increase to 91.8, 92.1, 80.9 and 96.9% respectively. The univariate analysis showed that an age over 65 years and the presence of microcytosis are associated to a greater risk of colon cancer while after multivariate analysis only the presence of microcytosis resulted to be an independent predictive factor of cancer. CONCLUSIONS: Abdominal ultrasound presents high sensitivity, specificity, PPV and NPV in the diagnosis of colon cancer. The combination of an ultrasonography and a rectoscopy permits us to rule out the presence of a colorectal carcinoma. In patients with microcytosis of 65 years and over, if there is strong clinical suspicion, a negative ultrasound may not be sufficient to rule out a colorectal neoplasia.  相似文献   
89.
Untested assumptions concerning ambulatory treatment have shaped mental health policies for decades. Three opinions prevail: (1) all use is alike; (2) any use leads to high use; and (3) all high use is discretionary and therefore excessive. These assumptions were tested, using data from a nationwide survey of ambulatory utilizers in Israel, a country that has universal coverage. The findings, based on detailed clinical and treatment records, challenge all three assumptions. Moreover, they document a diversity of clinical needs while also verifying substantial variations in the type, frequency, and duration of treatment provided to meet those needs. In brief, Israeli data do not confirm continuing concerns by policy makers about uncontrollable use of services with expanded mental health coverage. Special policy limitations on mental health treatment should be reconsidered in light of empirical evidence from a system without the restrictions that exist in the United States.  相似文献   
90.
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