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991.
992.
BACKGROUND: This study was designed to estimate the cost-effectiveness of expanding the human immunodeficiency virus (HIV)-testing protocol for donated blood beyond screening for HIV antibodies to further reduce the risk of HIV transmission through transfusion. STUDY DESIGN AND METHODS: A Markov decision analysis model was developed to estimate the cost-effectiveness of HIV antibody testing (at a cost of $5/unit) and of adding to that protocol a second HIV test, either plasma p24 antigen detection or RNA polymerase chain reaction (PCR) (at costs of $5/unit and $8/unit, respectively). Test efficacy was projected from anticipated window-period reductions (6 days for p24 antigen, 11 days for RNA PCR), and donor seroconversion rates were derived from the Retrovirus Epidemiology Donor Study. RESULTS: On the basis of current estimates of HIV prevalence rates in blood donors (1/10,000) and 16 million annual transfusions in the United States HIV antibody testing prevents 1568 cases of transfusion-acquired HIV infection each year at a cost of $3600 per quality-adjusted year of life saved. The addition of p24 antigen testing would prevent 8 more cases at a net additional cost of $60 million annually ($2.3 million/quality-adjusted life year); RNA PCR testing would prevent 16 more cases at a net additional cost of $96 million annually ($2.0 million/ quality-adjusted life year). CONCLUSION: Although expanding the donor HIV screening protocol with p24 antigen or RNA PCR testing will prevent rare cases of transfusion- associated HIV, the cost-effectiveness of such an addition is predicted to be far below that of most medical interventions. Thus, HIV test protocol additions are unlikely to provide cost-effective improvements to blood safety in the United States.  相似文献   
993.
大学生自尊特点与性别、年级及心理因素的关系   总被引:1,自引:0,他引:1  
目的:观察大学生自尊水平的特点。方法:于2005-11/2006-05选取江西省内6所高等院校,专业包括理工科、医学、师范类及文科类大学生793名。以751名大学生为研究对象,采用二维自尊量表进行调查,包含16个题项,每个维度8个题项。量表的重测信度为0.84和0.80,同质性信度为0.86和0.84;该量表测量整体自尊,分为自我喜欢和自我能力感两个维度。采用个别访谈的方法对自尊高分同学和自尊低分同学进行个别访谈,同时收集同学和班主任(辅导员)对该同学的评价。调查中使用半结构化访谈,访谈提纲的内容是依据症状自评量表各因子结合以往研究中自尊及其相关影响因素设计的,主要包括以下3个方面:①与焦虑有关的认知和事件。②与同学、老师以及朋友的关系。③对自我情感和心境的评价。为了缓解被访谈者的紧张情绪,还进行其他方面的交流。结果:发放问卷793份,收回780份。对所收回的问卷进行初步整理,剔除不符合要求的废卷后,获得有效问卷751份。①男生在整体自尊和自我能力感维度上得分高于女生,差异有显著性意义[分别为(49.5820±7.9979),(48.2091±8.2642)分;(23.3893±3.9680),(22.6963±4.2606)分,t=2.157,2.134,P<0.05]。男女生在自我喜欢维度上得分差异无显著性意义(P>0.05)。②在整体自尊和自尊两个维度上,各年级之间差异有显著性意义(P<0.05)。大二学生自我喜欢维度得分明显高于大一和大三学生[分别为(26.7353±5.1527),(25.2432±4.7695),(25.6045±5.2917)分,t=3.485,2.11,P<0.05,0.01];大二学生在自我能力感维度得分明显高于大一和大三学生[分别为(23.5588±4.2219),(22.5459±4.2285),(22.9718±3.9448)分,t=2.748,1.395,P<0.05,0.01]。③整体自尊和自尊两个维度,在性别与年级之间有交互效应。整体自尊和自我喜欢得分男生高于女生,大二学生得分高于大一和大三学生。自我能力感得分大二女生高于男生。在整体自尊和自尊两个维度,年级和专业之间有交互效应。④自尊与心理健康的关系:整体自尊高分者普遍具有正确的人生态度,满意的心境,对生活乐观,对未来充满了希望,和谐的人际关系、良好的个性和高尚的人格,同学之间关系融洽,能很好地相处,在与人交往中能做到尊重人、理解人,从不将自己的观点强加到他人的身上,能够平等地、宽容地了解、评价对方。而整体自尊低分者普遍存在焦虑情绪,人际关系不和谐和不能恰当地认同自己,或是莫名其妙地自傲,或是无缘无故地自卑,经常有意无意地掩饰自己的不足,心理特别敏感、脆弱,失落感极强,经不起风浪的折腾,存在严重的心理冲突,回避矛盾,无法保持平衡的心理状态。结论:大学生自尊水平存在性别、年级差异,并与心理健康症状存在明显相互作用关系。  相似文献   
994.

Objective

To explore the potential relationship between erectile dysfunction (ED), low testosterone levels, and the Charlson Comorbidity Index (CCI).

Material and methods

Cross-sectional study on patients referred to the andrology unit in 7 Spanish centers. The ED was diagnosed and graded using the International Index of Erectile Function (IIEF-5) score. Total testosterone, the prevalence of each comorbidity, and the CCI were compared between patients with different grades of ED. Besides, the correlation between total testosterone and the CCI score, the influence of each comorbidity, and the ED severity on the CCI was assessed in a multiple linear regression.

Results

The study included 430 men with a mean age of 61 years. The mean CCI was 3.5, and mean total testosterone 15.2 nmol/L; 389 (91%) subjects had some grade of ED: 97 (23%) mild, 149 (35%) mild-to-moderate, 86 (20%) moderate, and 57 (13%) severe. The increase in ED severity was significantly associated with a decrease in total testosterone (P = .002), and an increase in the CCI score (P < .001). Testosterone levels were significantly lower in patients with obesity, diabetes, hypercholesterolemia, and hypertriglyceridemia (P < .05). However, only the prevalence of diabetes and hypertension was significantly associated with the severity of ED. The multivariate analysis including variables related to all assessed comorbidities, total testosterone levels, and the DE severity significantly predicted the CCI score (P < .001, R2 = .426). The severity of ED significantly contributed to this model (P = .011), but total testosterone did not (P = .204).

Conclusions

The CCI is significantly associated with the ED severity, but it shows a weak correlation with the testosterone levels.  相似文献   
995.
正ISBN-10:0323476635ISBN-13:978-0323476638Elsevier出版社2018年11月出版240页本书由腰椎间融合术(lumbar interbody fusion,LIF)领域资深外科专家及主要技术革新者编撰,重点阐述微创及开放LIF手术技术的最新进展,全面介绍极外侧、斜外侧、直接外侧入路以及横突间入路、轴向入路和内窥镜下入路等成熟入路方式的具体步骤。本书有如下特点:注重技术差异、每一术式优缺点以及并发症的防治手段;高质量影像  相似文献   
996.
Safety of blood donations following a natural disaster   总被引:1,自引:0,他引:1  
To evaluate the relative safety of blood donations given in response to a major disaster, donor demographics and infectious disease test results were compared for donations made during the 10 days following the October 17, 1989, San Francisco Bay Area earthquake and those made during the preceding 6 months. These comparisons were made for donations given to the regional blood center in the area that was immediately affected by the disaster (Irwin Memorial Blood Centers) and for those given in an unaffected region (Los Angeles/Orange Counties Region, American Red Cross Blood Services). The rate of donation increased more than 200 percent during the 5 days following the earthquake in both the disaster-affected and unaffected regions. Both the disaster-affected and unaffected regions observed significant increases in the proportions of donations by first-time donors, by persons aged 20 to 39 years, and by women. The rates of confirmed positivity for infectious disease markers for post-earthquake donations did not differ significantly from rates for homologous donations given during the preceding 6 months, particularly when the rates were adjusted for the increased representation of first-time donors. Approximately 39 percent of post-earthquake first-time donors gave blood again within the following 6-month period. It is concluded that donations given after major disasters are essentially as safe as routine donations and that active efforts to recruit these donors again can be undertaken without reservation.  相似文献   
997.
Storage of lymphocytes for later use in prospective epidemiologic studies of blood donors and transfusion recipients has been limited by the cost of separating peripheral blood mononuclear cells (PBMCs). When the Transfusion Safety Study began in 1985, it was decided to establish a cell repository of cryopreserved buffy coat (BC) samples, and thus far over 20,000 samples have been accumulated from enrolled subjects. To determine if these specimens could be used for polymerase chain reaction, a simple thawing and pelleting technique for recovering hemoglobin-free total white cells (WBCs) was developed. To validate the technique, parallel analysis was conducted of BCs, whole blood (WB), and PBMC samples from human immunodeficiency virus type 1 (HIV-1)- seropositive subjects. Immediate postthaw cell courts of 29 frozen- thawed (F-T) WB and BC samples averaged 90 percent of the prefreeze (input) values. Representative WBC populations were obtained by immediate pelleting. Amplification of HIV-1 gag sequences from F-T BCs and F-T WB was 94 and 75 percent, respectively, which is as sensitive as that obtained with freshly separated PBMC lysates. Quantitative HIV- 1 proviral load analysis by serial dilution of 23 F-T BCs and 8 WB lysates showed results comparable to those obtained with lysates of fresh PBMCs. Values for WBC differential and immunophenotyping could be applied to express viral load relative to total WBCs, PBMCs, or CD4+ cells. These results establish the basis for simplified virologic analysis of cryopreserved BC or WB specimens.  相似文献   
998.
Ninety-four erythromycin-susceptible and 107 erythromycin-resistant enterococcal strains (MIC of ≥512 μg/ml) were inhibited by the ketolide HMR3647 at MICs of ≤0.007 to 0.06 and 0.03 to 8 μg/ml, respectively. Eighteen vanA-positive isolates and 29 high-level-penicillin-resistant isolates, all of them erythromycin resistant, were inhibited by HMR3647 at an MIC range of 0.015 to 4 μg/ml. The new ketolide has excellent activity against Enterococcus species.  相似文献   
999.
It is known that conjugated linoleic acid (CLA) feeding decreases body adiposity but the mechanisms involved are not clear. The aim of this study was to analyse whether alterations in uncoupling protein (UCP) expression in white and brown adipose tissues (WAT and BAT, respectively) and in skeletal muscle may be responsible for the effect of trans-10, cis-12 CLA on the size of body fat depots in hamsters. Animals were divided into three groups and fed an atherogenic diet with different amounts of trans-10, cis-12 CLA (0 control, 0.5, or 1 g/100 g diet) for 6 weeks. CLA feeding reduced adipose depot weights, but had no effect on body weight. Leptin mRNA expression decreased in both subcutaneous and perirenal WAT depots, in accordance with lower adiposity, whereas resistin mRNA expression was not changed. Animals fed CLA had lower UCP1 mRNA levels in BAT (both doses of CLA) and in perirenal WAT (the low dose), and lower UCP3 mRNA levels in subcutaneous WAT (the high dose). UCP2 mRNA expression in WAT was not significantly affected by CLA feeding. Animals fed the high dose of CLA showed increased UCP3 and carnitine palmitoyl transferase-I (CPT-I) mRNA expression levels in skeletal muscle. In summary, induction of UCP1 or UCP2 in WAT and BAT is not likely to be responsible for the fat-reduction action of CLA, but the increased expression of UCP3 in skeletal muscle, together with a higher expression of CPT-I, may explain the previously reported effects of dietary CLA in lowering adiposity and increasing fatty acid oxidation by skeletal muscle.  相似文献   
1000.
We identified Rickettsia monacensis as a cause of acute tickborne rickettsiosis in 2 humans. Its pathogenic role was assessed by culture and detection of the organism in patients' blood samples. This finding increases the number of recognized human rickettsial pathogens and expands the known geographic distribution of Mediterranean spotted fever-like cases.  相似文献   
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