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101.

Background  

Sharing of tissue samples for research and disease surveillance purposes has become increasingly important. While it is clear that this is an area of intense, international controversy, there is an absence of data about what researchers themselves and those involved in the transfer of samples think about these issues, particularly in developing countries.  相似文献   
102.
Although physicians are known to experience more stress than other workers, knowledge is lacking on the course of stress from a longitudinal perspective. This study explored the course of and contributors to, different dimensions of early career job-stress among physicians by means of a nationwide mail survey, with a particular emphasis on stress relating to the work-home interference. All physicians graduating from all four Norwegian universities in 1993 / 94 (N=631), responded during their final year of medical school (N=522), during their internship (N=402), in their 4th postgraduate year (N=422), and in their 10th postgraduate year (N=390). The mean observation period was 9.2 yr (SD=0.5). The main outcomes were job stress dimensions derived from an established job stress questionnaire (Cooper / Tyssen), with emphasis placed on dimensions of the work-home interference. Stress relating to the work-home interference increased during the observation period for both genders (repeated measures: beta=0.06, p<0.05), whereas stress relating to emotional pressure, time pressure, and fear of complaints and criticism, decreased. Stress relating to the work-home interference increased during their early career, mainly due to a lack of adaptive reduction in work hours and an increased number of children. Neuroticism, conscientiousness, and lack of support from one's partner and colleagues, appeared to be predictive of this stress.  相似文献   
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CD73/ecto‐5′‐nucleotidase is a key enzyme in the regulation of purinergic signaling and inflammatory reactions. It hydrolyzes extracellular AMP into adenosine, which dampens immune cell activation, and reduces leukocyte trafficking. By comparing CD73 expression and function in mononuclear and endothelial cells (ECs) of blood and lymph, we show that extracellular purines and CD73 activity have differential effects in these two vascular systems. We found that CD8‐positive T lymphocytes and CD19‐positive B lymphocytes in human lymph expressed high levels of CD73 and other purinergic enzymes and adenosine receptors. Soluble CD73 was less abundant in human lymph than in serum, whereas CD73 activity was higher in afferent lymphatic ECs than in blood ECs. Adenosine signaling improved barrier function and induced sprouting of human blood, but not lymphatic, ECs in vitro. Similarly, using CD73‐deficient mice we found that CD73 controls only blood vascular permeability at selected lymphoid organs under physiological conditions. Thus, both vascular and lymphatic arms of the immune system synthesize the components of purinergic signaling system, but surprisingly they use CD73 differentially to control endothelial permeability and sprouting.  相似文献   
105.
Mund E  Christensson B  Grönneberg R  Larsson K 《Chest》2005,127(5):1714-1721
BACKGROUND: Chronic dry cough without dyspnea and wheezing is a well-known condition that is considered to be clinically overrepresented in women. The etiology and morphology remain unknown in many cases despite thorough investigations. DESIGN: To examine inflammatory cells and the lymphocyte profile in the lower airways and blood in women with chronic cough of unknown etiology. SETTING: University hospital department of respiratory medicine. PARTICIPANTS: Twenty-five otherwise healthy women with idiopathic cough and 11 age-matched healthy control women, all nonatopic nonsmokers. MEASUREMENTS: In order to characterize the cough, a careful standardized interview of the patients was made. Lung functions were tested. Cells were collected by BAL and analyzed for differential cell counts separate in the bronchial (first) wash and in the pooled peripheral washes (BAL fluid). The lymphocyte profile in BAL fluid and blood was characterized by dual-color flow cytometry. RESULTS: Eleven female patients formed a specific group with a history of a dry, nonproductive cough that always started in connection with an airway infection coinciding with menopause. Neither exercise, climate, nor seasonal change influenced the cough. BAL fluid contained an increased number of T (CD3+) lymphocytes: median. Seventy-three percent of T lymphocytes were T-helper lymphocytes (CD4+). A median of 57% of the BAL fluid T cells expressed HLA-DR activation marker compared with a median of 20% in the control subjects and in the other 14 included patients with chronic cough but with minor expectoration periodically (p < 0.001 and p < 0.0001, respectively). No differences between the groups were found in the blood. CONCLUSIONS: HLA-DR-activated CD4+ lymphocytic airway inflammation with a low number of eosinophils was identified in a group of nonsmoking, nonatopic otherwise healthy women patients with dry cough of life-long character. The disease appeared exclusively in connection to menopause.  相似文献   
106.
BACKGROUND: There is growing evidence that erectile dysfunction is a sentinel for future coronary artery disease. Recently published studies have shown signs of impaired coronary endothelial function in patients with erectile dysfunction, without clinical cardiovascular disease and diabetes. We evaluated the magnitude of coronary vasodilatory dysfunction in men with erectile dysfunction, as compared with men with impaired glucose metabolism (impaired fasting glucose or diabetes) and healthy controls. METHODS: We investigated men aged 68-73 years with erectile dysfunction (n=12), age-matched men with impaired glucose metabolism, who all proved to have erectile dysfunction (n=15), and age-matched male controls (n=12). Erectile dysfunction was evaluated using the International Index of Erectile Function (IIEF)-5 questionnaire. Coronary flow velocity reserve in the left anterior descending artery was examined using Doppler ultrasound and intravenous adenosine provocation. RESULTS: Coronary flow velocities at rest did not differ between the three groups, but maximum coronary flow velocity was significantly lower in the erectile dysfunction group (P=0.004) and in the impaired glucose metabolism group (P=0.019), as compared with controls. There was no difference between the erectile dysfunction and impaired glucose metabolism groups. Coronary flow velocity reserve was reduced in the erectile dysfunction group (P=0.026) compared to controls, but was similar compared to the impaired glucose metabolism group. In multivariate analysis including all groups, erectile dysfunction score was the only independent predictor of reduced coronary flow velocity reserve (P=0.020). CONCLUSIONS: The magnitude of early coronary endothelial and smooth muscle cell dysfunction in otherwise healthy men with erectile dysfunction was comparable to that of patients with impaired glucose metabolism: a well known risk factor for coronary artery disease.  相似文献   
107.
Inhibitors of gastric acid secretion are efficient drugs in the treatment of acid-related diseases. However, by reducing gastric acidity, hypergastrinemia develops. Gastrin regulates its target cell, the enterochromaffin (ECL) cell, both functionally and trophically. Long-term hypergastrinemia in whatever species studied, has been shown to induce tumors originating from the ECL cell. In man, at least 10 years of hypergastrinemia, accompanied by high or reduced gastric acidity is necessary to induce ECL cell carcinoids. There are reports indicating development of ECL cell carcinoids after long-term treatment with proton pump inhibitors. Moreover, the ECL cell may give rise to gastric carcinomas of diffuse type, which have increased during the last decades. Furthermore, most of the carcinomas developing in patients with long-lasting hypergastrinemia are of ECL cell origin. Therefore, long-lasting iatrogenic hypergastrinemia induced by potent inhibitors of acid secretion may be expected to increase the occurrence of gastric carcinomas in the future.  相似文献   
108.
The aim of the present study was to investigate the prevalence of left ventricular (LV) thrombus formation and important determinants in patients with acute ST elevation myocardial infarction localized to the anterior wall treated with percutaneous coronary intervention (PCI) and dual-antiplatelet therapy. One hundred selected patients with ST elevation myocardial infarctions revascularized with PCI in the left anterior descending coronary artery were included. The patients participated in the Autologous Stem Cell Transplantation in Acute Myocardial Infarction (ASTAMI) trial. All were treated with aspirin 75 mg/day and clopidogrel 75 mg/day and underwent serial echocardiography and magnetic resonance imaging during the first 3 months after PCI. After 4 to 5 days, the ejection fraction and infarct size in percentage of the left anterior descending coronary artery area were assessed using single photon-emission computed tomography in addition to the ejection fraction by echocardiography. LV thrombi were detected in 15 patients during the first 3 months, 2/3 of them within the first week. No differences in baseline characteristics between the groups with and without LV thrombi were shown. However, in the thrombus group, significantly higher peak creatine kinase levels (6,128 vs 2,197 U/L, p <0.01), larger infarct sizes (82.5% vs 63.8%, p <0.01), and lower ejection fractions on single photon-emission computed tomography (35.5% vs 40.0%, p = 0.03) and on echocardiography (43.0% vs 46.0%, p = 0.03) were found compared to patients without LV thrombi. In conclusion, LV thrombus formation is a frequent finding in patients with anterior wall ST elevation myocardial infarction treated acutely with PCI and dual-antiplatelet therapy and should be assessed by echocardiography within the first week.  相似文献   
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