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BACKGROUND AND PURPOSE: Esophageal invasion (EI) by head and neck neoplasm has important prognostic and surgical management implications. Our purpose was to determine the accuracy of MR imaging for predicting neoplastic cervical esophageal invasion. METHODS: MR scans of the neck obtained from 22 patients with periesophageal masses were retrospectively reviewed independently and by consensus by two experienced head and neck radiologists who were unaware of surgical findings. The patients were selected from clinical, radiologic, or pathologic reports suggesting EI. The following imaging criteria for EI were evaluated: effacement of periesophageal fat planes, circumferential mass, paraesophageal lymph nodes, luminal size, wall thickening, increased T2 wall signal, and wall enhancement. There were eight patients with EI and 14 patients without EI, as confirmed by surgical findings or pathologic examination. RESULTS: The consensus criteria with the best sensitivities were any wall thickening (100%), effaced fat plane (100%), and any T2 wall signal abnormality (100%). The criteria with the best specificities were circumferential mass greater than 270 (100%) or 180 degrees (93%) and focal T2 wall signal abnormality (86%). The overall kappa value for the two readers for all criteria was 0.57 (moderate agreement). CONCLUSION: A circumferential mass or focal T2 signal abnormality on the esophageal wall suggests the presence of EI. An intact fat plane, absence of wall thickening, and no T2 wall signal abnormalities imply that the esophagus is not invaded.  相似文献   
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With the advent of more safe and user-friendly drugs in the modern era of psychopharmacology and their use in general practice, a brief discussion regarding the pharmacological aspect of the new drugs has been attempted in the present article so that they may be used more effectively in practice.  相似文献   
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Information about tobacco use prevalence, knowledge and attitude was assessed among school personnel in schools of West Bengal. Statistical analysis was done using SUDAAN and the C-sample procedure in Epi-Info. The school response rate was 100%. Current any smoking and smokeless tobacco use was reported by 30.9% and 13.1% school personnel, respectively. Current daily smoking, and smokeless tobacco use reported by 20.4%, and 5.8% school personnel respectively. Men reported significantly more for all kinds of daily tobacco use as compared to women. School tobacco control policy on three scales was reported poor (17.7-30%). However most of the school personnel felt need for such policies (82.7-93.6%). Teaching and training on tobacco was reported low (29.9%-50.4%). However most of the school personnel (79.1-93.6%) were supportive on different measures of tobacco control. Training of school personnel may provide students with essential tools to help them adopt and maintain a smoke free lifestyle.  相似文献   
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Objective: This study attempted to assess the respiratory and general health of ragpickers who rummage through the garbage dumps and landfill sites in India to collect and sell recyclable materials for a living. Methods: 98 ragpickers and 60 controls from Delhi, matched for age, sex, and socioeconomic conditions, were examined. Health data were obtained from questionnaire survey, clinical examination, and laboratory investigations. Lung function was evaluated by spirometry. Results: After controlling for smoking as a confounder, respiratory symptoms and lung function decrement were recorded in 94% and 52% of the ragpickers, respectively, compared with 56% and 34% of controls. The ragpickers showed a higher prevalence of low hemoglobin, high circulating eosinophil and monocyte counts, unhealthy gums, frequent diarrhea, and dermatitis, when compared with controls. Their sputum showed an abundance of alveolar macrophages, siderophages and inflammatory cells, and a very high frequency of squamous metaplasia and dysplasia of bronchial epithelial cells, suggesting inflammation and cellular changes in the airways. Conclusion: The ragpickers suffer from a multitude of health problems which seem related to their occupation.  相似文献   
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Behavioral agitation and prominent positive psychotic symptoms often characterize the acute presentation of schizophrenia. The clinical treatment goal is a rapid control of these symptoms. The relative efficacy of olanzapine, a novel antipsychotic drug, was compared with that of the conventional antipsychotic drug haloperidol. A post hoc analysis conducted on a large multicenter, double-blind, 6-week study of acute-phase patients with DSM-III-R schizophrenia or schizophreniform or schizoaffective disorders treated with olanzapine (5-20 mg/day) or haloperidol (5-20 mg/day) assessed the treatment effects on agitation (Brief Psychiatric Rating Scale [BPRS] agitation score) and positive symptoms (BPRS positive symptom score). Overall, olanzapine-treated patients experienced significantly greater improvement in behavioral agitation than did haloperidol-treated patients (last observation carried forward [LOCF]; p < .0002). Both groups showed similar reductions in agitation scores during the first 3 weeks of therapy; olanzapine was associated with significantly greater improvements at weeks 4, 5, and 6 (observed cases [OC]). Similarly, patients with predominantly positive psychotic symptoms experienced significantly greater improvement in BPRS positive symptom scores with olanzapine compared with haloperidol (LOCF; p = .013). In olanzapine-treated patients, improvement in BPRS agitation and positive symptom scores was significantly greater at weeks 4, 5, and 6 (agitation scores, p < or = .01; positive symptom scores, p < .05) (OC). These data suggest that olanzapine may be considered a first-line treatment for the patient in an acute episode of schizophrenia.  相似文献   
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Cytochrome P450 (CYP450) has widely been implicated for drug-drug interactions (DDI) in the pharmaceutical industry. Inhibition or induction of this enzyme family has led to withdrawal of multiple drugs from the market leading to major time and financial losses for the pharmaceutical industry. CYP450 plays a prevailing role in the biotransformation of a large number of structurally diverse drugs. Few isoenzymes of the CYP enzyme family (CYP3A4, 2D6 and 2C9 family) are mainly involved in metabolism of most of the drugs. To avoid such interactions and potentially minimize DDI, major pharmaceutical organizations prefer to incorporate CYP enzyme screening at an early stage of their discovery program. While this has been a prevalent practice in the pharmaceutical industry lately, there is very limited literature available reviewing the relationship between chemotypes and CYP isoforms. This review will collate literature pertaining to CYP-inhibition modulation through physicochemical parameters and chemical modification and thus bring to focus commonly used trends by medicinal chemists world-wide.  相似文献   
19.
Particulate matter less than PM10 and aromatic chemicals formed during incomplete combustion of organic matter are major environmental pollutants because of their toxic potential. The present study reports on the respiratory morbidity pattern of people exposed to auto exhaust as a result of the traffic load consisting of three varieties of vehicles (heavy, medium, and light) at three different points: North (B), South (E), and Central (C) regions of Kolkata, India. Particle size distribution was analyzed by an Anderson cascade impactor and volatile organic compounds (VOCs) were analyzed by sorbent tube and capillary gas chromatography with flame ionization detector. Levels of VOCs, particularly benzene and toluene (at B, 15.2 and 20.1 μg/m3; at E, 67.4 and 74.6 μg/m3, and at C, 40.7 and 61.3 μg/m3, respectively), were found to be appreciably high in three sites in Kolkata compared with the values reported by the U.S. EPA. PM10 concentrations also have been found to be higher than the Central Pollution Control Board of India’s permissible standard (≤10 μm: B, 535.9; E, 909.2; C, 1114.5 μg/m3; <10–3.3 μm: B, 269.8 μg/m3; E, 460.1; C, 679.2 μg/m3; and <3.3–0.4 μm: B, 266.1; E, 449.1; C, 435.3 μg/m3). Pulmonary function tests (PFT) of 505 inhabitants were performed in the three different areas using Spirovit SP-10 and Wrights peak flowmeter. The traffic load in the vicinity supported the occurrence of higher respiratory functional deterioration. PFT status showed restrictive (3.76%), obstructive (3.17%), and combined restrictive and obstructive types (1.98%) of impairment. Higher restrictive impairments in males might be due to their combined occupational and environmental exposures. The rate of increase of the number of vehicles on the roads of the city adds to the risk of greater problems due to exposure to hazardous substances that are less than PM10, in particular, polycyclic aromatic hydrocarbons and VOCs. An erratum to this article can be found at  相似文献   
20.
Several studies have shown that patients' expectancies for the development of nausea following chemotherapy are robust predictors of that treatment-related side effect, and some studies have shown that interventions designed to influence expectancies can affect patients' reports of symptoms. In this randomized, multicenter, Community Clinical Oncology Program trial, we investigated the effect of an expectancy manipulation designed to reduce nausea expectancy on chemotherapy-induced nausea in 358 patients scheduled to receive chemotherapy treatment. Patients in the intervention arm received general cancer-related educational material plus specific information about the efficacy of ondansetron, specifically designed to diminish nausea expectancy. Patients in the control arm received only the general cancer-related educational material. Nausea expectancy was assessed both prior to and following the educational intervention. We observed a significant reduction in nausea expectancy in the intervention group (P=0.024) as compared to the control group (P=0.34). In the intervention group, patients' expectations of nausea assessed prior to the intervention correlated significantly with average nausea (r=0.27, P=0.001), whereas nausea expectancy assessed following the intervention did not (r=0.1, P=0.22). Although the expectancy manipulation reduced patients' reported expectations for the development of nausea, the occurrence of nausea was not reduced. Furthermore, post-intervention nausea expectancy compared to pre-intervention expectancy was less predictive of subsequent nausea. Explanations for these findings include the possibility that the expectancy manipulation was not strong enough, and the possibility that changing nausea expectancies does not change occurrence of nausea.  相似文献   
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