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11.
Submitral ventricular aneurysm is a thoroughly studied pathology but is not well known due to its rarity. Clinically, it is manifested by symptoms and signs of heart failure, mitral regurgitation and/or ventricular arrhythmias, and may be associated with thromboembolic phenomena and myocardial ischemia due to compression of the coronary arteries by the aneurysm. A rare complication of this type of aneurysm is rupture into the left atrium. Transthoracic echocardiography plays an important role in the definitive diagnosis of this pathology, although the role of transesophageal echocardiography in the evaluation of these patients is less known. We report a case of a submitral ventricular aneurysm complicated by rupture into the left atrium, which was diagnosed by transesophageal echocardiography.  相似文献   
12.
Pulmonary embolism (PE) is an important health problem and often a major clinical challenge, not only because of the low specificity of its clinical manifestations but also because of the increasing number of medical circumstances that are risk factors for this illness and the importance of early identification, since prompt and appropriate treatment can decrease mortality from this disease by about 25%. In recent years research on PE has been extensive, directed mainly at trying to determine and characterize its risk factors, establish new clinical probability algorithms, develop new diagnostic methods and put existing ones into perspective, seek new therapeutic approaches (pharmacological and non-pharmacological), and above all establish protocols that can guide the clinician from the stage of clinical suspicion to measures to prevent recurrence. It was the authors' aim to review the most significant literature on this subject, in order to produce a text that reflects the state of the art concerning PE and that can be used as a guide in the clinical approach to this pathology.  相似文献   
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14.
BACKGROUND: Seroreversion, negativation of anti-hepatitis C virus previously positive, is sometimes found in some chronic hepatitis C-sustained responders (SRs) to antiviral therapy. AIMS: To determine the probability of seroreversion in SR treatment with Interferon and Ribavirin, and lymphocyte T helper (CD4+) reactivity to HCV antigens. METHODS: Thirty SR were followed on average for 54.8 months. Anti-HCV was tested by third generation test. Peripheral blood mononuclear cells (PBMCs) were isolated from venous blood and cultured to evaluate CD4+ proliferation in response to 2 microg/ml of eight HCV recombinant antigens from core, NS3, NS4, NS5 regions. RESULTS: Seroreversion was verified in 23% of patients (7/30), appearing at 47.5+/-24.0 months. The probability of anti-HCV loss in this group was 25% at 56 months after ending therapy. In 57% (4/7), anti-HCV returned to positive. These 7 SR patients with seroreversion also showed weaker CD4+ reactivity in 5% of tests (3/56) than the remaining 23 anti-HCV-positive SRs who showed stronger reactivity in 18% of tests (33/184), P=0.036. CONCLUSIONS: One-quarter of the SR showed seroreversion of anti-HCV and weaker CD4+ specific HCV proliferation than those who remained anti-HCV positive. The data suggest that complete viral eradication is a possible and achievable clinical objective.  相似文献   
15.
Treatment and prognostic factors in patients with hepatocellular carcinoma.   总被引:4,自引:0,他引:4  
INTRODUCTION: Hepatocellular carcinoma is a leading cause of death from cancer worldwide. Survival of patients depends on tumor extension and liver function, but yet there is no consensual prognostic model. AIMS: To evaluate the influence on survival of pretreatment parameters (clinico-laboratorial, liver function, tumor extension, Okuda and Cancer of the Liver Italian program (CLIP) staging) and treatment modalities. METHODS: We retrospectively analyzed 207 patients, diagnosed between 1993 and 2003. The initial treatment was: surgery--six patients; radiofrequency ablation--21; percutaneous ethanol injection--29; transarterial chemoembolization--49; tamoxifen--49; supportive care alone--53. Factors determining survival were assessed by Kaplan-Meier method and Cox regression models. RESULTS: Median survival was 24 months. In univariate analysis, Child-Pugh classification and Model for end-stage liver disease (MELD) score, portal vein thrombosis (PVT), tumor size, number of lesions, Okuda and CLIP scores were all associated with prognosis (P < 0.001). Alpha-fetoprotein levels were not predictive of survival. Independent predictors of survival were ascites, bilirubin, PVT and therapeutic modalities (P < 0.001). In early stage hepatocellular carcinoma (HCC), survival was similar for both percutaneous ablation modalities, either radiofrequency or ethanol injection (P = NS). In advanced HCC, survival was better in patients receiving tamoxifen than supportive care alone (P < 0.001). CONCLUSION: This study reinforces the importance of baseline liver function (Child-Pugh classification and MELD score) in the survival of patients with HCC, although staging systems allowed the stratification of patients in different prognostic groups. Ascites, bilirubin and PVT were independent pretreatment predictors of survival. All treatments influenced the patient's outcome, whether in early or advanced stages.  相似文献   
16.
This study aimed to investigate whether endothelial cells are damaged and to evaluate fibrinolytic system function in patients with type 2 diabetes. For this proposal, plasma levels of von Willebrand factor (an endothelial marker of injury), homocysteine (an inductor of endothelial injury), D-dimer (a marker of coagulation cascade activation) and plasminogen activator inhibitor-1 (a fibrinolysis marker) were measured in individuals with both type 2 diabetes and high blood pressure, with type 2 diabetes, with high blood pressure and in healthy control individuals. No significant differences among groups were observed for von Willebrand factor and homocysteine plasma levels. The type 2 diabetes and high blood pressure group presented a significant difference to the other groups for D-dimer and also presented high values for plasminogen activator inhibitor-1. The high blood pressure group and type 2 diabetes group presented separately higher values of plasminogen activator inhibitor-1 compared with the control group. High levels of D-dimer and plasminogen activator inhibitor-1 in patients with type 2 diabetes and high blood pressure with normoalbuminuria therefore indicate a state of hypercoagulability and hypofibrinolysis, despite no evident microvascular injury supported by normal levels of von Willebrand factor and homocysteine.  相似文献   
17.
OBJECTIVE: The objective of this study was to assess the efficiency of topical applications of podophyllin resin (25%) (P) versus podophyllin resin (25%) together with acyclovir cream (5%) (PA) in the treatment of oral hairy leukoplakia (OHL) in accordance with the following criteria: (1) number of applications necessary for the total clinical resolution of OHL; (2) correlation between the decrease of lesion size and the number of applications; (3) total clinical resolution of OHL; and (4) clinical reevaluation 12 months after the end of treatment. STUDY DESIGN: Forty-six OHLs were treated with P (P group) or with PA (PA group). Applications were performed weekly. Student t, Fisher exact, and Pearson correlation tests were used for statistical analysis. RESULTS: All 24 lesions from the PA group presented total clinical resolution while 4 lesions from the P group did not. The P group required up to 25 applications performed weekly while the PA group required up to 18. Observed was a negative significant association between the size of the lesions and the number of applications performed weekly in the PA group. CONCLUSIONS: The present study demonstrated the following: (1) P and PA topical treatments presented a similar average number of applications performed weekly; (2) both groups showed the same clinical response at 12 months post-therapy; and (3) PA presented a 100% clinical resolution and a continuous decrease in OHL size over the course of weekly applications.  相似文献   
18.
We conducted an exploratory investigation in a community in Haiti to determine the prevalence of Cyclospora cayetanensis infection and to identify potential risk factors for C. cayetanensis infection. In 2001, two cross-sectional stool surveys and a nested case-control study were conducted. In 2002, a follow-up cross-sectional stool survey was conducted among children < or =10 years of age. Stool specimens from study participants and water samples from their wells were examined for Cyclospora and other intestinal parasites. In stools, the prevalence of infection with Cyclospora in persons of all ages decreased from 12% (20 of 167 persons) in February 2001 to 1.1% (4 of 352 persons) in April 2001, a 90.8% decrease. For children < or =10 years of age, the prevalence rates were 22.5% (16 of 71 children) in February 2001, 3.0% (4 of 135 children) in April 2001, and 2.5% (2 of 81 children) in January 2002. Use of the water from the artesian well in the northern region of the community versus the one in the south was the only risk factor associated with Cyclospora infection in multivariate analyses (odds ratio, 18.5; 95% confidence interval, 2.4 to 143.1). The water sample from one of the nine wells or water sources tested (one sample per source) in January 2001, shortly before the investigation began, was positive for Cyclospora by UV fluorescence microscopy and PCR. None of the water samples from the 46 wells or water sources tested during the investigation (one sample per source per testing period, including the artesian wells) were positive for Cyclospora. Further studies are needed to assess the role of water as a possible risk factor for Cyclospora infection in Haiti and other developing countries.  相似文献   
19.
A C Moura  M Mariano 《Immunology》1996,89(4):613-618
In general, the majority of bacteria are pre-inflammatory when injected in experimental animals. However, Mycobacterium leprae has no inflammatory effect when injected into mouse footpad, but using the delipidated mycobacteria we observed a mild significant increase in footpad oedema. Other mycobacteria, Mycobacterium bovis-BCG or M. tuberculosis induce a strong paw oedema. Furthermore, M. leprae reduced locally the BCG-induced inflammatory reaction in mouse footpad, whereas delipidated M. leprae did not influence this reaction. Both M. leprae and M. leprae cell wall lipids blocked immune phagocytosis in vivo by inflammatory macrophages (from an induced focus). In contrast delipidated M. leprae stimulated the phagocytosis reaction. Neither intact M. leprae. delipidated M. leprae, nor its lipids had any toxic effect on macrophages or on cell migration. Although M. leprae did not interfere on cell influx and cell type in an induced-inflammatory site, this mycobacterium led to the appearance of a distinct cell population in vivo. The hypothesis is that M. leprae would transform macrophages in epithelioid cells, suggested by morphology analysis of cells by fluorescence-activated cell sorter and observed under optic microscopy.  相似文献   
20.
Wiedemann‐Steiner syndrome (WSS) is a rare genetic disorder characterized by growth retardation, facial dysmorphism, hypertrichosis cubiti and neurodevelopment delay. It is caused by pathogenic variants in the KMT2A gene. This report describes two unrelated Portuguese patients, age 11 and 17 years, with a phenotype concordant with WSS and clinical and molecular diagnosis of WSS by the identification of two novel frameshift variants in the KMT2A gene. This work also highlights the presence of certain clinical features in patients with growth retardation and development delay and should draw attention to the diagnosis of WSS, when hirsutism, particularly hypertrichosis cubiti is present.  相似文献   
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