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91.
Naphthoquinones have been studied extensively due to their activity as topoisomerase inhibitors. These enzymes are critical to DNA replication in cells. β‐Lapachone (beta‐lap) is an o‐naphthoquinone chemically obtained from lapachol. This work results in a toxicological evaluation of beta‐lap in Wistar rats observing the following parameters: teratology, histology, hematology and serum biochemistry. The data demonstrate teratogenic action at the doses used, as well as hematological alterations in the total leukocytes, monocytes and segmented. The biochemical data demonstrated an increase in gamma glutamyl transferase, alkaline phosphatase and glutamate pyruvate transaminase levels. Histological study showed significant alterations in the spleen, however, the liver and kidney did not present significant alterations. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   
92.
BACKGROUND: Liver transplantation is accepted as effective therapeutic option for end-stage liver disease, including alcoholic liver disease AIM: To evaluate the outcome of liver transplantation for alcoholic liver disease in the Liver Transplantation Program at "Hospital de Clínicas" of the Federal University of Paraná, Curitiba, PR, Brazil. PATIENTS AND METHODS: It was performed a retrospective study of the patients who underwent liver transplantation for alcoholic end-stage liver disease between September 1991 and January 2001. The minimum abstinence period required was 6 months before liver transplantation. Identification of alcohol consumption after liver transplantation was determinated by information provided by patient or family and biochemical or histological anormalities. RESULTS: Twenty patients underwent liver transplantation for alcoholic liver disease in the study period, 95% (19/20) were men and the median age was 50 years (29-61 years). Seventy-five percent of the patients (15/20) had severe liver disfunction (Child C class) in the pre-transplant period. In six of them (30%) there was association with viral hepatitis and in one, with hepatocarcinoma. Median abstinence period before liver transplantation was 24 months, varying from 9 to 120 months. One-year and 3-year survival rate were 75% and 50%, respectively. The main complications were: acute cellular rejection (40%), chronic rejection (5%), hepatic artery thrombosis (15%), biliary complications (15%), bacterial or fungal infections (45%), cytomegalovirus infection (20%). Three patients returned to alcohol use after liver transplantation CONCLUSION: The survival of patients who received liver transplant for alcoholic cirrhosis are satisfactory. In the present study there was a small index of alcohol use after liver transplantation.  相似文献   
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Objective:To investigate the association between malocclusion/dentofacial anomalies and traumatic dental injuries (TDI) in adolescents.Materials and Methods:The sample of this cross-sectional study comprised 509 adolescents aged 11 to 14 years enrolled at public schools in the city of Osório, southern Brazil. Parents answered a structured questionnaire addressing demographic and socioeconomic characteristics. An examiner who had undergone a training and calibration exercise recorded malocclusion/dentofacial anomalies (Dental Aesthetic Index, DAI), TDI (Andreasen), and dental caries (World Health Organisation). Statistical analyses (SPSS software) involved Poisson regression with robust variance.Results:The prevalence of TDI was 11.6%, and the prevalence of defined, severe, and handicapping malocclusion was 24.0%, 21.6%, and 22.0%, respectively. The multivariate analysis demonstrated that the probability of TDI was approximately twofold higher among adolescents with severe malocclusion (prevalence ratio [PR] 2.22; 95% confidence interval [CI] 1.14–4.31) and handicapping malocclusion (PR 1.95; 95% CI 1.01–3.85) in comparison to those with normal occlusion or minor malocclusion. Defined malocclusion was not significantly associated with the outcome. Among the dentofacial anomalies evaluated, the probability of TDI was nearly twofold higher among adolescents with overjet greater than 3 mm (PR 1.96; 95% CI 1.14–3.37) and 2.2-fold higher among those with an abnormal molar relationship (PR 2.24; 95% CI 1.17–4.32), after controlling for confounding variables.Conclusions:Severe and handicapping malocclusion, accentuated overjet, and abnormal molar relationship were strongly associated with the occurrence of TDI. Future studies should investigate whether the treatment of these conditions can help reduce the occurrence of TDI in adolescents.  相似文献   
95.
Currently, the need to ensure adequate quality of air inside the living space but also the thermal efficiency of buildings is pressing. This paper presents the capacity of sheep wool heat-insulating mattresses to simultaneously provide these needs, cumulatively analyzing efficiency indicators for thermal insulation and indicators of improving air quality. Thus, the values obtained for the coefficient of thermal conductivity, and its resistance to heat transfer, demonstrate the suitability of their use for thermal insulation. The results of the permeability to water vapor characteristics on the sorption/desorption of water, air, demonstrate the ability to control the humidity of the indoor air and the results on the reduction of the concentration of formaldehyde, demonstrating their contribution to the growth of the quality of the air, and to reduce the risk of disease in the population.  相似文献   
96.
97.
Phosphoric acid has been suggested as an irrigant due to its effectiveness in removing the smear layer.

Objectives

: The purpose of this study was to compare the antimicrobial and cytotoxic effects of a 37% phosphoric acid solution to other irrigants commonly used in endodontics.

Material and Methods

: The substances 37% phosphoric acid, 17% EDTA, 10% citric acid, 2% chlorhexidine (solution and gel), and 5.25% NaOCl were evaluated. The antimicrobial activity was tested against Candida albicans, Staphylococcus aureus, Enterococcus faecalis, Escherichia coli, Actinomyces meyeri, Parvimonas micra, Porphyromonas gingivalis, and Prevotella nigrescens according to the agar diffusion method. The cytotoxicity of the irrigants was determined by using the MTT assay.

Results

: Phosphoric acid presented higher antimicrobial activity compared to the other tested irrigants. With regard to the cell viability, this solution showed results similar to those with 5.25% NaOCl and 2% chlorhexidine (gel and solution), whereas 17% EDTA and 10% citric acid showed higher cell viability compared to other irrigants.

Conclusion

: Phosphoric acid demonstrated higher antimicrobial activity and cytotoxicity similar to that of 5.25% NaOCl and 2% chlorhexidine (gel and solution).  相似文献   
98.
99.

Background

Severe anaemic foetuses of Rhesus (Rh) isoimmunised mothers are usually treated by intrauterine transfusion (IUT). It is helpful to determine the volume of blood necessary to raise the concentration of haemoglobin by 1.0 g/dL in response to intrauterine transfusions.

Methods

In this cross-sectional, observational study we evaluated 107 first IUT for the correction of anaemia caused by haemolysis triggered by maternal Rh immunisation. The concentration of foetal haemoglobin was determined in umbilical cord blood before and after the IUT. The variation in foetal concentration of haemoglobin after transfusion was compared between groups of hydropic and non-hydropic foetuses, between groups of foetuses with different degrees of anaemia and with groups of gestational age less than or more than 28 weeks. The t-test for averages and ANOVA were used to compare average differences among the groups. p values less than 0.05 were considered statistically significant.

Results

Fifty-five (61.4%) foetuses were found to be anaemic while hydrops was observed in 40 (44%) at the time of the IUT. The volume of red blood cell concentrate infused varied from 5 to 90 mL, with 11.2±1.5 mL being necessary to raise the circulating concentration of haemoglobin by 1.0 g/dL. The foetal response was not influenced significantly by either the degree of foetal anaemia (p=0.56) or the presence of hydrops (p=0.17). The foetuses with a gestational age of 28 weeks or less required a smaller volume of red blood cell concentrate than those with a gestational age of more than 28 weeks (9.3±5.4 mL and 13.4±4.8 mL, respectively; p<0.0001) in order to raise their concentration of circulating haemoglobin by 1.0 g/dL.

Conclusion

The volume of red blood cell concentrate necessary to correct anaemia in pregnancies complicated by Rh isoimmunisation must be considered carefully, since the response to the infusion of blood is peculiar in extremely premature infants. Hydrops and the degree of anaemia were not determinants of the change in the final concentration of circulating haemoglobin following the blood transfusion.  相似文献   
100.
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