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141.
Immunoglobulin kappa gene usage and somatic mutation patterns were studied in a series of 47 IGKV-J rearrangements amplified in 42 follicular lymphoma (FL) cases. The IGKV1-39/1D-39 gene predominated and was significantly over-represented compared to normal cells, autoreactive cells or other B cell lymphomas. The impact of somatic hypermutation varied significantly; nevertheless, mutation distribution patterns indicated pressure for preservation of the B cell receptor. In conclusion, the present series demonstrates biased usage of IGKV genes in FL and alludes to the important role of immunoglobulin kappa light chains in antigen selection of the clonogenic B cells in FL.  相似文献   
142.
Abstract We report the case of a 44-year-old white man who presented with progressively worsening crampy abdominal pain and distention. Deterioration of his clinical picture along with leukocytosis and radiographic evidence of severe colonic dilation rendered exploratory laparotomy necessary. Greatly distended and inflamed transverse and descending colon were evident and an extended left colectomy was performed. Characteristic changes of leukocytoclastic vasculitis in the serosal and muscular layers of the resected colon were demonstrated at histopathologic examination. Systemic leukocytoclastic vasculitis, usually coexisting with Henoch-Schönlein purpura, commonly affects the small bowel with clinical evidence of ischemia or bleeding. Colon involvement is infrequently reported in the context of systemic disease. Isolated colonic leukocytoclastic vasculitis without extraintestinal manifestations is rare. A previously unreported case of localized leukocytoclastic vasculitis of the left colon resulting in the impressive presentation of megacolon, without the presence of any precipitating factor or associated systemic disease is presented here, with an overview of the related literature.  相似文献   
143.
  • Severe mitral regurgitation (MR) may lead to worsening renal function due to a decrease in stroke volume, increase in systemic vascular resistance, and venous pooling.
  • Percutaneous treatment with MitraClip seems to improve renal function in certain patient groups.
  • Larger studies are needed to prove that MitraClip is the preferred strategy in patients with severe MR and chronic kidney disease
  相似文献   
144.
145.
Artificial Neural Network (ANN) models were developed and applied in order to predict the total weekly number of Childhood Asthma Admission (CAA) at the greater Athens area (GAA) in Greece. Hourly meteorological data from the National Observatory of Athens and ambient air pollution data from seven different areas within the GAA for the period 2001-2004 were used. Asthma admissions for the same period were obtained from hospital registries of the three main Children's Hospitals of Athens. Three different ANN models were developed and trained in order to forecast the CAA for the subgroups of 0-4, 5-14-year olds, and for the whole study population. The results of this work have shown that ANNs could give an adequate forecast of the total weekly number of CAA in relation to the bioclimatic and air pollution conditions. The forecasted numbers are in very good agreement with the observed real total weekly numbers of CAA.  相似文献   
146.
Reduced intracellular Mg concentrations in patients with acute asthma   总被引:2,自引:0,他引:2  
STUDY OBJECTIVES: To determine the intracellular and extracellular Mg concentrations in patients with acute asthma and their correlation with parameters expressing the disease severity. PATIENTS: Thirty patients with acute asthma (FEV(1), 56% predicted [SD, 14.5]), 20 patients with stable asthma (FEV(1), 97% predicted [SD, 10]), and 20 healthy subjects (FEV(1), 97% predicted [SD, 8]). METHODS: Mg concentrations in erythrocytes and plasma were measured four times: at hospital admission, after 2 days, after 5 days, and at hospital discharge. Percentage of predicted FEV(1) and peak expiratory flow rate variability were recorded simultaneously. Similar measurements were carried in all study groups. RESULTS: Mg concentrations of healthy subjects and patients with stable asthma remained unchanged in both plasma and erythrocytes. Initial Mg content in erythrocytes was significantly lower in patients with acute asthma (1.77 fmmol per cell; 95% confidence interval [CI], 1.71 to 1.83) compared to normal subjects (1.94 fmmol per cell; 95% CI, 1.82 to 2.00) and patients with stable asthma (1.92 fmmol per cell; 95% CI, 1.87 to 1.96) [p < 0.0001], and it increased significantly after the resolution of the exacerbation (from 1.77 fmmol per cell [95% CI, 1.71 to 1.83] at hospital admission to 1.90 fmmol per cell [95% CI, 1.83 to 1.98] at hospital discharge; p < 0.0001). No correlation was observed between parameters of disease severity and the initial values of Mg concentrations in erythrocytes and plasma. CONCLUSIONS: Acute asthma is associated with lower erythrocyte Mg content while plasma levels remain unchanged. This decrease in intracellular Mg content occurs regardless of the severity of the exacerbation and returns to normal values after control has been achieved.  相似文献   
147.
148.
High total homocysteine (tHcy) concentrations increase coronary disease risk. Therefore, the authors examined the relation between tHcy concentrations and the number of stenotic arteries in patients with ischemic heart disease (IHD). They enrolled 155 patients with IHD (135 men) who had undergone selective coronary angiography during the previous 2 years. These patients were divided into 4 groups according to the number of vessels (0, 1, 2, and 3) with > or = 70% stenosis. They also reviewed the major coronary risk factors for each patient (age, gender, hypertension, diabetes mellitus, dyslipidemia, cigarette smoking, obesity), and measured serum concentrations of tHcy, folate, vitamin B12 and lipids. There was a significant positive correlation (rs = 0.19; p = 0.017; n = 155) between tHcy serum concentration and the extent of coronary atherosclerosis, expressed by the number of coronary arteries with significant stenosis. Moreover, the number of affected vessels displayed a significant positive correlation with the presence of diabetes mellitus (rs = 0.30; p < 0.0001; n = 155) and serum concentrations of lipoprotein (a) (rs = 0.25; p < 0.05; n = 67) and a negative correlation with apolipoprotein A-I serum concentration (rs = -0.27; p < 0.01; n = 67). In this study, the serum concentrations of tHcy correlated with the extent of coronary atherosclerosis, independently of other classical risk factors, with the exception of diabetes mellitus.  相似文献   
149.
Background. Pancreatic pseudocysts (PP) are considered to be one of the major complications of acute, chronic, and posttraumatic pancreatitis. Their treatment has always been a surgical challenge. Surgical treatment was for many years the only choice in the management of PP. However, technological development has provided new alternatives in their management. Purpose. The purpose of this retrospective study is to present our experience in the treatment of PP and to define the criteria for the selection of the treatment method. Methods. During the past decade, 14 patients were treated for PP in our clinic. We classified our patients in three groups based on the treatment: A, conservative treatment; B, surgical treatment with internal drainage; and C, percutaneous external drainage (PED) under CT guidance. Results. Conservative treatment had excellent outcome when it was applied in patients with small cysts. Internal drainage was always successful, but patients needed more hospitalization and showed increased morbidity compared to PED. PED was successful in two of three patients. Conclusions. Conservative treatment is a good choice for small asymptomatic cysts, particularly for patients who are poor candidates for operation. Internal drainage is a good method of treatment and should be used as the first choice by experienced surgeons. Finally, PED is a good first choice for patients with a unilocular cyst and contraindications for surgery.  相似文献   
150.

Aim

To prospectively evaluate interferences between viruses of the upper respiratory tract in asymptomatic preschool children.

Methods

Nasal-pharyngeal swabs from 233 preschool aged children were prospectively collected over four consecutive time periods, during one school year. The samples were tested using a RT-PCR DNA/RNA microarray system for nine respiratory viruses.

Results

Respiratory syncytial virus (RSV) was a predictor of the presence of influenza virus (INFL) (OR: 9.12, CI: 1.52–54.75, p = 0.016), and similarly, INFL predicted the presence of RSV (OR: 4.01, CI: 1.14–14.16, p = 0.030). Also, rhinovirus (RV) was a predictor of adenovirus (ADV) presence (OR: 3.66, CI: 1.10–12.14, p = 0.034), and similarly, ADV predicted the presence of RV (OR: 4.05, CI: 1.02–16.05, p = 0.046). No other significant associations between viruses were observed.

Conclusion

Our results indicate that respiratory viruses found in carrier stage in asymptomatic children may interact with other viruses and even facilitate their settling in the upper respiratory tract. The pathophysiological role of these interactions is not yet clear.  相似文献   
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