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91.
Abstract: We investigated the effects of (1,4)‐α‐D‐glucan (α‐DG), a novel immune stimulatory drug from Tinospora cordifolia, on the concentration of pro‐ and anti‐inflammatory cytokines (interleukin [IL]‐1β, IL‐6, tumour necrosis factor‐α [TNF‐α], γ‐interferon [IFN‐γ] and IL‐10) in the lung and spleen of endotoxin‐stimulated juvenile rats. Experimental groups (n = 16/group) included controls with an intraperitoneal injection of saline, endotoxaemic rats with a non‐lethal dose of 10 mg/kg Escherichia coli endotoxin, and endotoxaemic rats treated with two doses of 10 mg/kg α‐DG, intraperitoneally, 2 and 4 hr after endotoxin injection. At 24 hr of treatment, rats were euthanized and lungs and spleen were removed for cytokines determination and lung injury. Endotoxaemia increased IL‐1β concentration by fivefold in both organs, while creating a moderate pulmonary hypercellularity (demonstrated by about 11% increase in the alveolar‐septal thickening and 11% decrease in the alveolar‐interstitial space ratio). In the lung, α‐DG treatment reduced concentrations of IL‐1β by 30% (p > 0.05), IL‐6 by 43% (p < 0.01), IFN‐γ by 46% (p < 0.01) and the anti‐inflammatory cytokine, IL‐10, by 31% (p > 0.05) compared to endotoxaemia. In the spleen, α‐DG treatment decreased the ratio of IL‐1β to IL‐10 by 55% (p < 0.05), demonstrating an anti‐inflammatory trend. These data suggest that α‐DG differentially modulates cytokine response in the lung and spleen and modifies the pro‐ and anti‐inflammatory balance during an early period of endotoxaemia in juvenile rats.  相似文献   
92.
93.
Idiopathic mid-aortic syndrome in children   总被引:1,自引:1,他引:0  
Mid-aortic syndrome (MAS) is an uncommon condition characterized by narrowing of the abdominal aorta and stenosis of its major branches. Our goal was to illustrate the presentation, diagnosis and management of six new cases of idiopathic MAS together with 96 cases of idiopathic MAS from the literature. The mean age of the 102 cases was 14.3 years (19 days to 49 years). Our patient who presented at 19 days of age is the youngest reported to date. Clinical presentations included hypertension (94%), claudication (17%), renal failure (4%) and intestinal ischemia (1%). Angiography was the diagnostic imaging study of choice. Renal arteries were involved in 91% of patients, while the superior mesenteric artery and celiac artery were involved in 35%. Thirteen percent of cases were managed medically, and the remainder was treated surgically. Our experience shows that initial conservative blood pressure management of idiopathic MAS is feasible unless medical control of hypertension is unsatisfactory, renal function is at risk or there are symptoms of claudication or intestinal ischemia. Careful timing and planning of a surgical intervention is possible for most cases and may, in select cases, be considered after completion of puberty to allow growth to be completed.  相似文献   
94.
Management and outcomes of patients with acute coronary syndromes (ACSs) may vary according to patient race and ethnicity. To assess racial differences in presentation and outcome in high-risk North American patients with non-ST-segment elevation (NSTE) ACS, we analyzed baseline racial/ethnic differences and all-cause death or nonfatal myocardial infarction (MI) in 6,077 white, 586 African-American, and 344 Hispanic patients through 30-day, 6-month, and 1-year follow-up. Frequencies of hypertension were 66% for whites, 83% for African-Americans, and 78% for Hispanics (overall p <0.001). Use of angiography was similar across groups. Use of percutaneous coronary intervention (46% for whites, 41% for African-Americans, and 45% for Hispanics, overall p = 0.046) and coronary artery bypass grafting (20% for whites, 16% for African-Americans, and 22% for Hispanics, overall p = 0.044) differed. African-American patients had significantly fewer diseased vessels compared with white patients (p = 0.0001). Thirty-day death or MI was 14% for whites, 10% for African-Americans, and 14% for Hispanics (overall p = 0.034). After adjustment for baseline variables, African-American patients had lower 30-day death or MI compared with white patients (odds ratio 0.73, 95% confidence interval 0.55 to 0.98). There were no differences in 6-month death or MI across racial/ethnic groups. In conclusion, baseline clinical characteristics differed across North American racial/ethnic groups in the SYNERGY trial. African-American patients had significantly better adjusted 30-day outcomes but similar 6-month outcomes compared with white patients.  相似文献   
95.
In this study, we have analyzed the chemical composition and antiproliferative activity of propolis from three different arid and semiarid regions of Sonora, Mexico. We identified and quantitated the main chemical constituents of propolis by HPLC-MS. The most abundant constituents of propolis were pinocembrin, pinobanksin 3-acetate, and chrysin. Sonoran propolis had a strong antiproliferative activity on both murine and human cancer cell lines in a concentration-dependent manner. The propolis constituents CAPE, galangin, xanthomicrol and chrysin showed significant antiproliferative activity on most of the cancer cells tested. DNA harvested from cancer cell cultures treated with Sonoran propolis exhibited a ladder of internucleosomal DNA cleavage characteristic of apoptosis. In summary, we have identified and quantitated the main constituents of Sonoran propolis. These propolis samples possess a strong antiproliferative activity on cancer cell lines.  相似文献   
96.
97.
Reorganization of skin during wound healing, inflammatory disorders, or cancer growth is the result of expression changes of multiple genes associated with tissue morphogenesis. We wanted to identify proteins involved in skin remodeling and select those that may be targeted for agonistic or antagonist therapeutic approaches in various disease processes. Full-thickness human skin was grafted to severe combined immunodeficient mice and injected intradermally with 38 different adenoviral vectors inserted with 37 different genes coding for growth factors, cytokines, proteolytic enzymes and their inhibitors, adhesion receptors, oncogenes, and tumor suppressor genes. Responses were characterized for infiltration of inflammatory cells, vascular density, matrix formation, fibroblast-like cell proliferation, and epidermal hyperplasia. Of the 17 growth factor vectors, 16 induced histological changes in human skin. Members of the VEGF and angiopoietin families induced neovascularization. PDGFs and TGF-betas stimulated connective tissue formation, and the chemokines IL-8 and MCP-1 attracted inflammatory neutrophils and monocytes, respectively. The serine protease uPA induced a vascular response similar to that of VEGF. Vectors with adhesion receptors, oncogenes and tumor suppressor genes had, with few exceptions, little effects on skin architecture. The overall results suggest that adenoviral vectors can effectively remodel the architecture of human skin for studies in morphogenesis, inflammatory skin disorders, wound healing, and cancer development.  相似文献   
98.
The aim of this study was to estimate the 1-year prevalence of migraine and the degree of the association of migraine with some sociodemographic characteristics of a representative sample of the adult population of Brazil. This was a cross-sectional, population-based study. Telephone interviews were conducted on 3848 people, aged 18–79 years, randomly selected from the 27 States of Brazil. The estimated 1-year gender- and age-adjusted prevalence of migraine was 15.2%. Migraine was 2.2 times more prevalent in women, 1.5 times more in subjects with > 11 years of education, 1.59 times more in subjects with income of < 5 Brazilian Minimum Wages per month, and 1.43 times more in those who do not do any physical exercise. The overall prevalence of migraine in Brazil is 15.2%. Migraine is significantly more prevalent in women, subjects with higher education, with lower income, and those who do not exercise regularly, independently of their body mass index.  相似文献   
99.
Visual identification of bacterially contaminated red cells   总被引:1,自引:0,他引:1  
There have been increasing numbers of reports of transfusion-acquired Yersinia enterocolitica bacteremia (including several fatal cases). Fifteen units of whole blood were inoculated with various concentrations of Y. enterocolitica serotype 0:3 and processed into AS-3 preserved red cells (RBCs). Consistent growth of the organism was found at inoculum concentrations greater than or equal to 10 colony-forming units per mL. In all 13 units of RBCs that supported the growth of Y. enterocolitica, a darkening in color (due to hemolysis and a decrease in pO2) was observed in the bag. The attached sample segments, which were sealed from the main unit, remained sterile and did not darken. This color change was apparent in all the contaminated units by Day 35, which was 1.5 to 2 weeks after the bacteria were first detected in cultures of the blood. Hence, by comparison of the color of the segment tubing with that of the unit itself, units grossly contaminated with Y. enterocolitica can be identified prior to transfusion. Moreover, review of photographs on file at the Centers for Disease Control revealed this dramatic color change in 2 units of blood that caused transfusion-transmitted sepsis (Enterobacter agglomerans and an unidentified gram-negative bacillus, not Yersinia sp.), which demonstrated that the color change was not limited to Y. enterocolitica. This method of visual identification of contaminated units of blood could decrease the incidence of posttransfusion bacterial sepsis.  相似文献   
100.
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