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41.
In countries with adequate resources, rates of perinatal mother-to-child-transmission (MTCT) of HIV can be as low as 2% or lower. To achieve this low rate of MTCT of HIV requires identification of women with HIV infection early in pregnancy, treatment of the pregnant woman with appropriate combination antiretroviral therapy, special interventions in maternal management during labor and delivery, and appropriate care of the newborn infant.Although many of the steps in preventing HIV MTCT fall to obstetrical care providers, practitioners focused on care of the newborn also play an important role in the prevention of perinatal HIV MTCT, follow-up to identify or exclude HIV infection in the infant, and ongoing care for children and families affected by HIV.  相似文献   
42.
The prevalence of depression is high among injection drug users (IDUs) and among those infected with the hepatitis C virus (HCV). Moreover, one of the drugs used in the standard treatment for HCV infection (interferon) has been known to exacerbate, underlying psychiatric disorders such as depression and has been associated with the development of major, depressive disorder among HCV-infected patients. For these reasons, the most recent National Institutes of Health consensus statement on the management of HCV infection recommends the identification and treatment of depression prior to the start of HCV treatment. This study aimed to examine the extent of current moderate/severe depressive symptoms in a cohort of HCV-infected IDUs as measured by two screening tools, the Center for Epidemiologic Studies Depression Scale (CES-D) and the Beck Depression Inventory (BDI). Subjects were participants in a multisite behavioral intervention trial among HCV-seropositive, human immunodeficiency virus-negative IDUs aged 18–35 years; the trial was designed to prevent secondary transmission of HCV and to enhance uptake of HCV treatment. Baseline data on demographics, risk behaviors, depression, alcohol use, and health care utilization were measured via audio computer-assisted self-interview. A factor analysis was conducted on each scale to examine the clustering of items used in each to measure depressive symptoms. Baseline depressive symptoms, as measured via the CES-D and the BDI, were also compared using Pearson’s correlation coefficient. Of 193 HCV-infected individuals enrolled to date, 75,6% were male, and 65.3% were white. Median age was 25.8 years. Factor analyses revealed that these scales measured depression differently; a distinct somatic component was present in the BDI, but not the CES-D. Using cutoff scores of 23 for the CES-D and 19 for the BDI, 44.0% and 41.5% of the participants were identified as having moderate/severe depressive symptoms, respectively. Over half (56.0%) were identified as having depressive symptoms  相似文献   
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44.
The purpose of this study was to determine the prevalence and correlates of attempted suicide among young injection drug users (IDUs) from six study sites in five US cities. Two thousand two hundred and nineteen participants 15-30 years of age underwent interviewer-administered questionnaires relating to self-reported drug use, sociodemographics, suicidal ideation and attempts, and exposure to violence. The 6-month prevalence of suicidal ideation and attempts was 35.8% (n = 795) and 7% (n = 156), respectively. Compared to those not reporting a recent (past 6 months) suicide attempt, those attempting suicide were more likely to have a lifetime history of mental health facility admission or sexual abuse. Participants receiving drug treatment at the time of the baseline interview (53.2% versus 37.1%, odds ratio [OR] = 1.93, 95% confidence interval [CI]: 1.39, 2.67) were also more likely to report a recent attempt; as were those reporting a history of experiencing violence. These associations persisted after adjusting for age, sex, race/ethnicity, study site, and other significant covariates by multiple logistic regression. These data suggest that increased access to drug treatment, community mental health, and violence prevention programs may decrease suicidal behavior among young injection drug users.  相似文献   
45.
Previously, we detected pathogenic (invasive) DNA in the appendices of two patients who later developed Crohn's disease (CD). This subsequent investigation is the first to evaluate a series of specimens from CD patients for the presence of pathogenic DNA. A total of 54 intestinal resection specimens from 52 patients with confirmed CD were evaluated. Lesional tissue was tested by polymerase chain reaction analysis for the presence of genes occurring only in pathogenic Primer pairs are specific for each species, with no known cross reactions with other bacteria. Forty normal bowel specimens, 30 cases of acute appendicitis, and 50 cases of various active colitides served as disease controls. Medical records were reviewed following polymerase chain reaction and histologic evaluation. A total of 17 of 54 resections (31%) contained DNA by polymerase chain reaction. Mesenteric lymph nodes were also positive in eight of these cases. All controls were negative. -positive patients had carried the diagnosis of CD for a median of 10 years before resection (range 1 month to 40 years). We report the first documentation of DNA in a series of CD cases. Further studies are needed, including serial study, over time, of -positive CD patients, as well as prospective studies of newly diagnosed CD patients for evidence of infection. Like previous studies associating infectious organisms with CD, much work remains to elucidate whether the presence of DNA is an epiphenomenon or actually a factor in the pathogenesis of CD.  相似文献   
46.
Wells RG  Havens PL 《Radiology》2003,228(2):370-378
PURPOSE: To assess the safety and efficacy of urokinase and alteplase for intrapleural fibrinolysis in children with parapneumonic pleural fluid collections. MATERIALS AND METHODS: A retrospective review was performed of 71 children with parapneumonic pleural fluid accumulations who were treated with thoracostomy tube placement and intrapleural instillation of either urokinase or alteplase. The procedures were performed with urokinase between September 2, 1995, and March 27, 1998, and with alteplase between March 30, 1998, and January 2, 2002. The medical records and daily chest radiographs were reviewed by a pediatric radiologist to ascertain demographic information, signs and symptoms, laboratory results, thoracostomy tube output, treatment details, and radiographic pleural thickness and lung opacification. Multiple variables were compared for the alteplase and urokinase groups by using univariate and multivariate statistics. We defined primary treatment success as resolution of signs and symptoms at the time of discharge, without surgical intervention. RESULTS: Primary treatment success was 98% for alteplase and 100% for urokinase, with no major complications. Greater pleural fluid drainage occurred with alteplase than urokinase during the 1st (P =.001) and 2nd (P =.002) days of fibrinolytic therapy, and for the duration of thoracostomy drainage (P <.001). Multivariate models showed greater total drainage with alteplase (P <.001), greater patient age (P <.001), larger tube size (P =.002), and greater volume of drainage during the 24 hours prior to fibrinolysis (P <.001). CONCLUSION: Intrapleural fibrinolysis with urokinase or alteplase facilitates thoracostomy tube drainage of parapneumonic pleural fluid. With the dosing regimen used in this study, alteplase produces greater thoracostomy tube output than does urokinase.  相似文献   
47.
An integrative literature review was conducted to investigate studies on adverse events reported in medical, health services, and nursing literature. The review was guided by the method proposed by Jackson ( 1980 ) and Ganong (1987). Three questions shaped the review: (a) What terms are used to denote adverse events? (b) What purposes drive adverse events research? and (c) What data sources are used to study adverse events? Adverse events was the dominant term, the study of adverse events as an outcome variable was the prevailing research purpose, and monitoring or screening the patient clinical record and self‐reported incidents by health care professionals were the main data sources. Future research is recommended to conceptualize and study adverse events. © 2003 Wiley Periodicals, Inc. Res Nurs Health 26:398–408, 2003  相似文献   
48.
OBJECTIVE: To determine the prevalence of heparin-dependent platelet antibodies (HDPA) in children requiring heparin for >5 days after cardiopulmonary bypass surgery. DESIGN: Prospective, observational study. SETTING: Tertiary care pediatric intensive care unit. PATIENTS: Thirty children were enrolled: 15 patients <30 days old and 15 patients between 30 days and 12 yrs of age. INTERVENTIONS: Detection of HDPA by heparin-platelet factor 4 enzyme-linked immunosorbent assay after 5-10 days of postoperative heparin exposure. Positive or equivocal results were confirmed with serotonin release assay. MEASUREMENTS AND MAIN RESULTS: There were no confirmed cases of HDPA in this study (95% confidence interval 0-11.6%). Despite the lack of HDPA, the study population was at high risk of thrombosis with symptomatic clot developing in six patients (20%). Clinical models developed in adults to determine the pretest risk of heparin-induced thrombocytopenia were not valid in this study population. CONCLUSIONS: The prevalence of HDPA in children after cardiopulmonary bypass surgery is low. After bypass surgery, critically ill children are at risk of developing thrombosis from multiple etiologies, and suspicion of heparin-induced thrombocytopenia needs to be confirmed with laboratory testing including a functional assay.  相似文献   
49.
Recently, considerable interest has been given to photodynamic therapy of cancer using δ-aminolaevulinic acid to induce protoporphyrin IX as the cell photosensitizer. One advantage of this modality is that protoporphyrin IX is cleared from tissue within 24 h after δ-aminolaevulinic acid administration. This could allow for multiple treatment regimens because of little concern regarding the accumulation of the photosensitizer in normal tissues. However, the haem biosynthetic pathway would have to be fully functional after the first course of therapy to allow for subsequent treatments. Photosensitization of cultured R3230AC rat mammary adenocarcinoma cells with δ-aminolaevulinic acid-induced protoporphyrin IX resulted in the inhibition of porphobilinogen deaminase, an enzyme in the haem biosynthetic pathway, and a concomitant decrease in protoporphyrin IX levels. Cultured R3230AC cells exposed to 0.5 mM δ-aminolaevulinic acid for 27 h accumulated 6.07 × 10−16 mol of protoporphyrin IX per cell and had a porphobilinogen deaminase activity of 0.046 fmol uroporphyrin per 30 min per cell. Cells cultured under the same incubation conditions but exposed to 30 mJ cm−2 irradiation after a 3-h incubation with δ-aminolaevulinic acid showed a significant reduction in protoporphyrin IX, 2.28 × 10−16 mol per cell, and an 80% reduction in porphobilinogen deaminase activity to 0.0088 fmol uroporphyrin per 30 min per cell. Similar effects were evident in irradiated cells incubated with δ-aminolaevulinic acid immediately after, or following a 24 h interval, post-irradiation. There was little gain in efficacy from a second treatment regimen applied within 24 h of the initial treatment, probably a result of initial metabolic damage leading to reduced levels of protoporphyrin IX. These findings suggest that a correlation may exist between the δ-aminolaevulinic acid induction of porphobilinogen deaminase activity and the increase in intracellular protoporphyrin IX accumulation. © 1999 Cancer Research Campaign  相似文献   
50.
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