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We studied the prevalence and risk factors for thrombocytopenia among 299 drug users and 461 homosexual men. The prevalence of thrombocytopenia was 3.3% in HIV-negative homosexual men, 8.7% in HIV-negative drug users, 16.4% in HIV-positive homosexual men, and 36.9% in HIV-positive drug users. With multivariate logistic regression HIV-seropositivity (odds ratio 3.3), a history of injecting drugs (OR 3.9), an increased number of lymphocytes (OR 0.44), an increased number of neutrophils (OR 0.53) and a larger mean platelet volume (OR 2.8) were independently and significantly associated with thrombocytopenia. The results obtained with linear regression analysis were consistent with the results of the logistic regression. The higher prevalence of thrombocytopenia among drug users was related to a history of intravenous drug use but not to recent injecting. The mechanisms causing thrombocytopenia among HIV-positives and HIV-negatives seem to be related, but HIV-infection seems to enhance thrombocytopenia in an independent way.  相似文献   
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Experiments are described the results of which sustain the hypothesis that resistance against complement haemolysis, which is a characteristic of the red cells of patients with chronic cold agglutinin disease, is due to the following mechanism: when red cells react with cold auto-agglutinins in vivo, they are either haemolysed immediately, or, due to an unknown factor, escape direct haemolysis. In the latter case β1E and β1A disappear from the cell membrane. To the sites where these proteins have been attached once, no new β1E or β1A molecules can be bound. Full complement activation thus becomes impossible.  相似文献   
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Despite the effectiveness of combination antiretroviral therapy in the treatment of people living with HIV/AIDS (PLWHA), nonadherence to medication has become a major threat to its effectiveness. This study aimed to estimate the prevalence of self-reported irregular use of antiretroviral therapy and the factors associated with such an irregularity in PLWHA. A cross-sectional study of PLWHA who attended two referral centers in the city of Recife, in Northeastern Brazil, between June 2007 and October 2009 was carried out. The study analyzed socioeconomic factors, social service support and personal habits associated with nonadherence to antiretroviral therapy, adjusted by multivariable logistic regression analysis. The prevalence of PLWHA who reported irregular use of combination antiretroviral therapy (cART) was 25.7%. In the final multivariate model, the irregular use of cART was associated with the following variables: being aged less than 40 years (OR = 1.66, 95%-CI: 1.29-2.13), current smokers (OR = 1.76, 95%-CI: 1.31-2.37) or former smokers (OR = 1.43, 95%-CI: 1.05-1.95), and crack cocaine users (OR = 2.79, 95%-CI: 1.24-6.32). Special measures should be directed towards each of the following groups: individuals aged less than 40 years, smokers, former smokers and crack cocaine users. Measures for giving up smoking and crack cocaine should be incorporated into HIV-control programs in order to promote greater adherence to antiretroviral drugs and thus improve the quality of life and prolong life expectancy.  相似文献   
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Purpose:?To study the factors associated with progression, recovery and death from different grades of disability in elderly people.

Method:?The sample included 3198 participants of the PAQUID (‘Personnes Agées QUID’) cohort, aged 65 and over and community-dwellers at baseline. Subjects were re-interviewed 1, 3, 5, 8 and 10 years after baseline. A five-state Markov model was used to estimate transition intensities between four grades of disability and toward death. We used a hierarchic scale of disability, which combines basic and instrumental activities of daily living and mobility. Several explanatory variables were investigated: medical, personal and environmental factors.

Results:?The factors associated with progression and/or no recovery of disability were cardiovascular diseases, stroke and diabetes, low cognition, visual impairment and dyspnoea (for pathologies and impairments), older age, female gender, low educational level (for risk factors), depression (for intra-individual factor) and being married, recent hospitalization and number of drugs (for extra-individual factors). Older age, male gender, tobacco consumption and living in an urban area were associated with mortality.

Conclusions:?These findings confirm the independent contribution of each group of variables in the disablement process and stress their different impact on progression of disability or on recovery from different grades of disability.  相似文献   
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IntroductionEpithelial ovarian cancer are the most frequent of ovarian cancer, their prognosis is very bad. The aim of this study is to describe the diagnosis, the treatment and to assess the survival rate of the patients.MethodsIt was a retrospective study realized at the Cancer Institute of Dakar from December 2000 to January 2007. We have collected 117 patients with epithelial ovarian cancer. The mean age was 49 years. Patients were comprised: 22 stage I, 32 stage II, 35 stage III and 26 stage IV. Primary surgery was performed to 34 patients and the other patients were treated with chemotherapy and surgery. The survival rate was assessed by Kaplan-Meier method and the Logrank test had allowed to compare the survival among age and optimal surgery.ResultsOptimal surgery R0 was done in 20 cases and surgical resection R2 was performed in 45 cases. Pathological exam had found 65 serous cystadenocarcinoma, 28 mucinous cystadenocarcinoma and 21 endometrioid cystadenocarcinoma, one malignant tumor of Brenner. Overall survival at five years was 13.3%. The survival among optimal surgery was 16.3 and 2.3% for suboptimal surgery. There was no significant difference of the survival among patients who were less than 40 years old (P  =  0.334).ConclusionPrognosis of epithelial ovarian cancer is worse in Senegal as like as in the world. To improve the survival of our patients, we must detect the early diagnosis of these tumors and to introduce the neoadjuvant chemotherapy before optimal surgery.  相似文献   
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Hypertensive crisis (HC) includes hypertensive urgency (HU) and hypertensive emergency (HE). There is scarcity of data on the epidemiology of patients presenting with HC in Cameroon. The aim of this study was to determine the prevalence, clinical characteristics, and outcome of HU and HE. We conducted a cross‐sectional study from June 2018 until June 2019. The criteria to define a hypertensive crisis were systolic and/or diastolic blood pressure ≥180/110 mm Hg. We compared HU vs HE. Out of the 1536 patients admitted, 95(6.2%) had a HC. There were 49(51.6%) men and 56 (58.9%) had a HE. The mean age was 51.1 ± 14.9 years. A history of hypertension was found in 75.3% of the patients but only 24.2% were on treatment. 33.7% consumed alcohol and 24.2% had chronic kidney disease. Headache (34.7%), dyspnea (34.7%), and neurological deficit (23.2%) were the most common symptoms. Patients with HE had higher systolic and diastolic blood pressures though the difference was not significant. The most frequent forms of HE were acute left ventricular failure with pulmonary edema (44.6%), intracerebral hemorrhage (21.4%), and cerebral infarction (16.1%). The most commonly prescribed medication was labetalol (44.2%). Mean length of hospital stay was 8.4 days. Patients with HE had a longer hospital stay (9.8 vs 6.3 days, P < .001). In‐hospital case fatality was 6.3%. Hypertensive crisis accounted for 6.2% of admissions in the medical unit with HE being more common than HU. Acute left ventricular failure with pulmonary edema and stroke were the most frequent target organ lesions in HE.  相似文献   
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