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Four different sites were selected for sampling of water samples--river, pond, hand-pump, and municipal water. These were analyzed for physico-chemical and bacteriological parameters with special reference to aeromonads following standard methods. Chlorinated disinfectants in the form of powder and liquid (drops) were used for the treatment. Out of which powdered forms were found to be more effective. Although chlorination reduced the density of aeromonads to some extent but still its presence cannot be behold.  相似文献   
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Alzheimer disease: operating characteristics of PET--a meta-analysis   总被引:6,自引:0,他引:6  
PURPOSE: To assess the operating characteristics of positron emission tomography (PET) by using fluorine 18 fluorodeoxyglucose (FDG) in the diagnosis of Alzheimer disease. MATERIALS AND METHODS: Articles published between 1989 and 2003 were identified in the MEDLINE, CINAHL, and HealthSTAR databases. Articles were selected if FDG PET was performed with a dedicated scanner and the resolution was specified, if standard criteria were used for the diagnosis of Alzheimer disease, if at least 12 human subjects with Alzheimer disease were enrolled in the study, if clinical diagnosis or histopathologic findings were used as the reference standard, and if sufficient data were provided to construct a 2 x 2 table. Two reviewers independently abstracted data regarding the operating characteristics (sensitivity and specificity) of PET and evaluated the study quality. A meta-analysis was performed by constructing a summary receiver operating characteristic curve and by combining the sensitivity and specificity values by using a random-effects model. RESULTS: Fifteen articles that met the inclusion criteria showed heterogeneity in sensitivity and specificity estimates that were not related to quality features with no plausible explanations. The summary sensitivity of PET was 86% (95% CI: 76%, 93%), and the summary specificity was 86% (95% CI: 72%, 93%). CONCLUSION: The specificity and sensitivity of FDG PET are limited by both study design and patient characteristics. Therefore, the clinical value of these parameters is uncertain; future research on the use of PET in the diagnosis of Alzheimer disease needs to focus on current limitations to be of practical relevance in clinical settings.  相似文献   
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PROBLEM: Spontaneous mastitis or induced infections mimicking mastitis reduce pregnancy rates in ruminants. The effect of immunization with either a mastitis-related pathogen component, peptidoglycan-polysaccharide (PG-PS), or killed Streptococcus pyogenes on pregnancy outcome was investigated. METHOD OF STUDY: Ewe lambs were immunized with PG-PS (n = 50) or killed bacteria (n = 50) or were not immunized (control, n = 100). Titers of PG-PS immunoglobulin G (IgG) were detected by enzyme-linked immunosorbent assay (ELISA). Ewes were bred by rams at synchronized estrus. All immunized ewes and half of the ewes not immunized were challenged with PG-PS on day 5 after breeding. Pregnancy maintenance was evaluated. RESULTS: Although the proportion of ewes pregnant at day 42 after breeding did not differ among treatments, the probability of pregnancy decreased with total dose of PG-PS (P < 0.05). CONCLUSIONS: Immunization of ewe lambs with PG-PS or killed S. pyogenes did not improve pregnancy maintenance. Furthermore, the toxic streptococcal component decreased pregnancy rate in immunized sheep in a dose-dependent manner.  相似文献   
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Two new triterpenoids were isolated from the n-hexane extract of seeds of Nigella sativa Linn. and identified as cycloart-23-methyl-7,20,22-triene-3β,30-diol (1) and cycloart-3-one-7,22-diene-24-ol (2). In addition, two aliphatic compounds and two known sugars were isolated from alcohol extract, and identified as 4-hydroxy undecyl nonanoate (3), 14,20-dimethyl heptacosanol (4), maltose (5), and sucrose (6). They were characterized on the basis of spectral analysis and by comparing literature data. Extraction and transportation study of sugars were also investigated, which evaluated biological phenomena.  相似文献   
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Pharmacogenomics is the study of interindividual genetic variability, which plays a significant role in defining drug response and toxicity. As research has graduated from studying single candidate genes to whole-genome scans, pharmacogenomics is beginning to make its impact on the therapeutics of complex CNS disorders, such as schizophrenia, Parkinson's disease and Alzheimer's disease. Alzheimer's disease is a progressive complex disorder, where genetic predisposition interacts with environmental factors. With conventional therapeutics only providing symptomatic treatment, the current focus of the pharmaceutical industry is on novel strategies with an etiopathogenic orientation. In this review, we have summarized the current knowledge of pathogenetic mechanisms of Alzheimer's disease, with a focus on the known relevant molecules and the potential of pharmacogenomics in translating this knowledge of human genome variability into efficacious and safer therapeutics.  相似文献   
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36 patients with pleural effusion were studied clinically with pertinent investigations and pleural fluid analysis. The pleural fluid analysis was done with routine protocol including study of traditional parameters like protein and cell count and additional parameters like pleural LDH, GOT(AST) and their ratio with serum LDH and GOT respectively. The utility of these parameters was studied critically. Amongst the isolated parameters cell count enjoyed highest (100%) specificity and positive predictive value. LDH ratio had highest (79.1%) sensitivity. Pleural LDH showed highest (52.6%) negative predictive value and diagnostic accuracy (69.4%). Amongst the combination of two parameters protein with LDH ratio had highest (87.5%) sensitivity, cell count with LDH ratio showed highest specificity (100%), positive predictive value (75%) and diagnostic accuracy (88.9%). Amongst the combination of three parameters pleural protein and cell count with LDH ratio and GOT ratio respectively enjoyed best sensitivity (87.5%), specificity and positive predictive value (100%), negative predictive value (80%) and diagnostic accuracy (90.6%). Similarly competent were the combinations offour parameters namely p rotein and cell count with LDH and its ratio and GOT and its ratio respectively. Combination of all parameters exhibited similar degree of utility.  相似文献   
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