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1.
Abstract: Background : Despite extensive literature on the topic, it is uncertain if grand (para ≥ 5) and great grand (para ≥ 10) multiparity are associated with adverse birth outcomes. We critically evaluate the evidence for and against the existence of adverse maternal and/or fetal outcomes in high parity women. Methods : An electronic search of MEDLINE and other bibliographic databases (Current Contents, EMBASE, and CAB) was conducted, and all relevant articles in English language were retrieved. Results : Findings on the association between high parity and maternal‐fetal birth outcomes are not consistent. Although the older literature tends to suggest that multiparity is a risk factor for negative birth outcomes, more recent reports are not supportive. Comparison across studies was further complicated by confounding factors like maternal age, socioeconomic status, and levels of prenatal care, as well as by variations in study designs and in the definition of parity itself. Furthermore, most studies that examined women of extreme parity (para ≥ 10) were handicapped by inadequate power. Conclusions : After accounting for quality, culture, and degrees of associations, the preponderance of evidence seems to point to possible existence of heightened risk for certain medical complications and placental pathologies among women of extreme parity. The literature also provides reasonable evidence for a higher‐than‐expected likelihood for occurrence of fetal macrosomia with advanced parity.  相似文献   
2.
BACKGROUND: The diagnosis of hepatitis B virus (HBV) has until recently been based on traditional serologic methods targeting viral antigens and antibodies to viral proteins. The development of molecular methods allowing for the quantitation of HBV DNA is proving clinically valuable for monitoring therapy and detecting early treatment failures. OBJECTIVES: Here we report a new real-time (LightCycler) quantitative PCR for the detection of HBV DNA based on sequence specific hybridisation probes (designed in-house), targeting the HBV surface antigen. STUDY DESIGN: The assay was evaluated using a 10-fold dilution series of standard HBV DNA [Eurohep standard reference 1, genotype A, HBsAg subtype adw with a unitage of 10(6) WHO. i.u./ml] and 89 clinical serum samples. The performance was measured against a quantified standard HBV DNA working reagent (NIBSC code 98/780) and the sensitivity compared with our conventional thermal-block PCR. RESULTS AND CONCLUSION: Real-time PCR detected HBV DNA in 45% (40/89) and thermal-block PCR in 16% (14/75) of clinical samples. Results for 26 samples were below the detection limit of the thermal-block PCR but could be quantified by real-time (LightCycler) PCR. The LightCycler assay was at least 5 logs more sensitive than thermal-block PCR and could detect HBV in a linear range between 5 and 10(7) i.u. per reaction. The broad generic nature of the PCR primers coupled with the enhanced sensitivity and specificity of the fluorescent hybridisation probes makes this assay potentially valuable for both routine diagnostic and epidemiological work.  相似文献   
3.
Healthcare for the elderly population presents enormous challenges, which are further complicated by ethnicity-related socioeconomic disparities in the United States. We set out to determine the predictors of hospital admissions in the elderly by conducting a retrospective cohort analysis of a nationally representative sample of community-dwelling individuals aged 70 and older in 1984 (n = 7541). Multivariate logistic regression analysis of data from the Longitudinal Study on Aging revealed that race, health status, type of family relationship, and activities of daily living (ADL) are significant predictors of hospitalization among the elderly. Older blacks are less likely to be admitted into the hospital, compared to their white counterparts (OR 0.68, 95%CI 0.52-0.89). Elderly persons who perceive their health status as being fair or poor are three times as likely to be hospitalized than those who perceived their health status as excellent (OR 2.99, 95%CI 2.15-4.15). Those with impairment in activities of daily living are twice as likely to be confined to the hospital than those without impairment (OR 1.78, 95%CI 1.64-1.96). Elderly persons living with nonrelatives are three times as likely to be admitted for short hospital stays than those living with spouses (OR 2.90, 95%CI 1.44-5.82). Future identification of predictors of hospital admissions in the elderly may help characterize those at risk and perhaps allow for focused and timely intervention.  相似文献   
4.
BACKGROUND AND PURPOSE: The emergent multidrug-resistant (MDR) Salmonella typhimurium definitive phage type 104 (DT104) is a public and veterinary health problem not only due to its wide host range and potential for enhanced virulence, but also the difficulty associated with its control. There is thus a need to investigate possible antigens of MDR DT104. METHODS: Using standard protocols, whole cell lysates, outer membrane extracts and cell-free ultracentrifuge supernatants of selected isolates of MDR DT104 were prepared, electrophoretically separated and tested for their antigen-antibody reactivity in comparison with a non-MDR DT104 strain. RESULTS: Protein antigens of both strain types were recognized by antibodies in chick serum in a similar manner for all methods of antigen preparation used. CONCLUSIONS: This study did not find differences between the antibody recognition of MDR DT104 and that of the non-MDR DT104 strain tested. This observation should strengthen the quest for the possible use of vaccines to control this emergent strain in poultry.  相似文献   
5.

Ethnopharmacological relevance

African trypanosomiasis is one of the neglected tropical diseases caused by different species of trypanosomes that affect both human and livestock with devastating consequences in the continent. Most of the affected populations commonly use traditional medicinal plants for the treatment of the disease. Consequently, this prompted ethnopharmacological research activities on the anti-trypanosomal activity of a number of these African medicinal plants in order to validate their ethnomedicinal use. Furthermore, such studies could lead to the identification of chemical leads for the development of newer anti-trypanosomal agents from those plants. This review aims to provide updated information on the ethnopharmacological evidence of African medicinal plants with anti-trypanosomal activity.

Methods

Literature was collected via electronic search (PubMed, Sciencedirect, Medline and Google Scholar) from published articles that report on the in vitro or in vivo anti-trypanosomal activity of plants that were collected from different parts of Africa.

Results

African medicinal plants investigated for in vitro and in vivo anti-trypanosomal activity from January 1993 to October 2013 are systematically compiled and all the in vivo studies are critically discussed. A total of 264 plant species belonging to 79 families were investigated for anti-trypanosomal activity. However, only 48 bioactive anti-trypanosomal compounds were successfully isolated in pure forms. Furthermore, some of the plants were investigated for possible ameliorative effects on the trypanosome-induced pathological changes out of which 18 plants were reported to be effective while a few others were not. In spite of interesting preclinical ethnopharmacological evidence for anti-trypanosomal activity, not a single African medicinal plant was investigated in a clinical study.

Conclusion

Several African medicinal plants have demonstrated promising anti-trypanosomal effects but the studies on the anti-trypanosomal potentials of these plants are not taken beyond proof of concept stage. It is hoped that the article would stimulate future clinical studies because of the paucity of knowledge in this area.  相似文献   
6.
The aim of this study is to assess the stress distribution on the bone tissue and bone-implant interface of a customized anatomic root-analog dental implant (RAI) by means of finite element analysis (FEA) for different types of bone density. A mandibular right second premolar was selected from the CBCT database. A DICOM file was converted to an STL file to create a CAD model in FEA software. The bone boundary model was created, while bone density types I–IV were determined. Von Mises stress was measured at bone tissues and bone-implant interfaces. To validate the models, the RAI was 3D printed through a laser powder-bed fusion (L-PBF) approach. The results revealed that all RAI designs could not cause plastic deformation or fracture resulting in lower stress than the ultimate tensile stress of natural bone and implant. Compared to a conventional screw-type implant, RAIs possess a more favorable stress distribution pattern around the bone tissue and the bone-implant interface. The presence of a porous structure was found to reduce the stress at cancellous bone in type IV bone density.  相似文献   
7.
Context Despite the reported anticarcinogenic activity of lophirones B and C, no scientific information exists for its activity in rat hepatocytes.

Objective Effect of lophirones B and C on aflatoxin B1 (AFB1)-induced oxidative stress, and DNA fragmentation in rat hepatocytes was investigated.

Materials and methods Wistar rat hepatocytes were incubated with lophirones B and C (1?mg/mL) or sylimarin (1?mg/mL) in the presence or absence of AFB1. For an in vivo study, rats were orally administered with lophirones B and C, and/or AFB1 (20?μg/d) for 9 weeks.

Results Lophirones B and C lowered AFB1-mediated increase in nitric oxide, superoxide anion radicals, caspase-3 and fragmented DNA. Lophirones B and C attenuated AFB1-mediated decrease in superoxide dismutase, catalase, glutathione peroxidase, glutathione reductase, and reduced glutathione. Also, lophirones B and C attenuated AFB1-mediated increase in conjugated dienes, lipid hydroperoxides and malondialdehyde in rat hepatocytes. Furthermore, AFB1-mediated alterations in alkaline phosphatase, alanine aminotransferase, aspartate aminotransferase, albumin, total bilirubin and globulin in rat serum were significantly annulled in lophirones B and C-treated rats.

Conclusion This study revealed that lophirones B and C prevented AFB1-induced oxidative damage in rat hepatocytes.  相似文献   
8.
Earth materials have been used in construction as safe, healthy and environmentally sustainable. It is often challenging to develop an optimum soil mix because of the significant variations in soil properties from one soil to another. The current study analyzed the soil properties, including the grain size distribution, Atterberg limits, compaction characteristics, etc., using multilinear regression (MLR) and artificial neural networks (ANN). Data collected from previous studies (i.e., 488 cases) for stabilized (with either cement or lime) and unstabilized soils were considered and analyzed. Missing data were estimated by correlations reported in previous studies. Then, different ANNs were designed (trained and validated) using Levenberg-Marquardt (L-M) algorithms. Using the MLR, several models were developed to estimate the compressive strength of both unstabilized and stabilized soils with a Pearson Coefficient of Correlation (R2) equal to 0.2227 and 0.766, respectively. On the other hand, developed ANNs gave a higher value for R2 than MLR (with the highest value achieved at 0.9883). Thereafter, an experimental program was carried out to validate the results achieved in this study. Finally, a sensitivity analysis was carried out using the resulting networks to assess the effect of different soil properties on the unconfined compressive strength (UCS). Moreover, suitable recommendations for earth materials mixes were presented.  相似文献   
9.
10.
The anti-Trypanosoma brucei brucei activity in vitro and in vivo of a lactone-rich fraction of Vernonia blumeoides leaves (VBLF) and its potential in alleviating trypanosome-induced anemia and organ damage were investigated. Gas chromatography–mass spectrometry (GC–MS) analysis of VBLF revealed the presence of a number of lactone-containing compounds. In an in vitro study, VBLF showed concentration-dependent activity and was further used to treat T. brucei brucei-infected rats. The VBLF treatments, especially at 300 mg/kg body weight (BW), significantly (P < 0.05) kept the parasites reduced during the entire experimental period compared with the infected untreated group. At the end of the experiment, the trypanosome-induced anemia and hepatic damage were significantly (P < 0.05) alleviated in all the VBLF treatment groups, but renal damage was only prevented in the 200 and 300 mg/kg BW treatment groups. Furthermore, the trypanosome-induced increase in the relative weights of liver, spleen and kidney were significantly (P < 0.05) alleviated by the 300 mg/kg BW VBLF treatment. It was concluded that orally administered VBLF, especially at 300 mg/kg BW, possessed antitrypanosomal activity and could alleviate parasite-induced anemia and organ damage.  相似文献   
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