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91.
The typical CT appearance of a duodenal diverticulum is of a rounded air collection with or without fluid or contrast. An unusual case in which gas bubbles mixed with particulate matter mimicked faecal material in the large bowel is presented here. A similar appearance has been described in abnormally dilated small bowel, usually associated with obstruction, and is probably due to stasis of undigested food.  相似文献   
92.
The vestibular function was extensively investigated in 75 patients suffering from migraine. Pathological findings were present in 62 patients (82.6%). With the exception of position nystagmus, vestibular abnormalities were not related to migraine characteristics. Fifty-six patients were treated with flunarizine 10 mg daily for three months. A favourable effect on headache was obtained in 44 patients (78.5%). Flunarizine therapy influenced significantly gaze nystagmus and position nystagmus. The latter tended to be related to anti-migraine efficacy. Other electronystagmographic parameters were not substantially influenced. The authors assume that the vestibular abnormalities in migraine are side phenomena, the clinical relevance of which, at least during the headache-free phase, is not yet well understood.  相似文献   
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94.
OBJECTIVE: The aim of this study was to assess the ability of a single 24-h dietary recall (24HDR) and food questionnaires (FQ) to predict plasma carotenoid levels at the ecological level by assessing the relationship between mean plasma carotenoid levels and mean intake of fruit and vegetables measured by 24HDR and FQ across 16 European regions. DESIGN: A random subsample of 3089 subjects was included, stratified by age and gender. They provided blood samples and dietary information between 1992 and 2000 as part of the European Prospective Investigation into Cancer and Nutrition. RESULTS: Using Spearman's correlation coefficients, the correlations between mean regional 24HDR fruit and vegetable variables and corresponding mean plasma carotenoid levels were generally higher than the correlations using FQ means. The highest correlation was between the 24HDR citrus fruit variable and beta-cryptoxanthin (r = 0.90). For 24HDR, total fruits and vegetables were highly correlated with lutein, zeaxanthin, and beta-cryptoxanthin (r = 0.83-0.87), while vegetables were more closely related with lutein (r = 0.69) and zeaxanthin (r = 0.68), and fruits correlated with zeaxanthin (r = 0.87) and beta-cryptoxanthin (r = 0.84). Root vegetables (r = 0.81) and total carrots (r = 0.71) were well correlated with alpha-carotene. In the multivariate models adjusting for age, body mass index, and season, and using observations of means stratified by sex and region, the association was generally higher for 24HDR compared to FQ. CONCLUSION: Mean regional intakes of fruits and vegetables in several European countries were closely correlated with corresponding mean plasma levels of individual carotenoids. Fruits and vegetables measured by 24HDR were generally better able to predict plasma carotenoids at the ecological level.  相似文献   
95.
Vegetables and fruits are rich in carotenoids, a group of compounds thought to protect against cancer. Studies of diet-disease associations need valid and reliable instruments for measuring dietary intake. The authors present a measurement error model to estimate the validity (defined as correlation between self-reported intake and "true" intake), systematic error, and reliability of two self-report dietary assessment methods. Carotenoid exposure is measured by repeated 24-hour recalls, a food frequency questionnaire (FFQ), and a plasma marker. The model is applied to 1,013 participants assigned between 1995 and 2000 to the nonintervention arm of the Women's Healthy Eating and Living Study, a randomized trial assessing the impact of a low-fat, high-vegetable/fruit/fiber diet on preventing new breast cancer events. Diagnostics including graphs are used to assess the goodness of fit. The validity of the instruments was 0.44 for the 24-hour recalls and 0.39 for the FFQ. Systematic error accounted for over 22% and 50% of measurement error variance for the 24-hour recalls and FFQ, respectively. The use of either self-report method alone in diet-disease studies could lead to substantial bias and error. Multiple methods of dietary assessment may provide more accurate estimates of true dietary intake.  相似文献   
96.

Background  

The Severe Acute Respiratory Syndrome (SARS) was a newly emerged infectious disease which caused a global epidemic in 2002–2003. Sequence analysis of SARS-coronavirus isolates revealed that specific genotypes predominated at different periods of the epidemic. This information can be used as a footprint for tracing the epidemiology of infections and monitor viral evolution. However, direct sequencing analysis of a large number of clinical samples is cumbersome and time consuming. We present here a simple and rapid assay for the screening of SARS-coronavirus genotypes based on the use of fluorogenic oligonucleotide probes for allelic discrimination.  相似文献   
97.
We report the therapeutic effects of liver-specific expression of a short-chain acyl-CoA dehydrogenase (SCAD) transgene in the SCAD- deficient mouse model. Transgenic mice were produced with a rat albumin promoter/enhancer driving a mouse SCAD minigene (ALB-SCAD) on both the SCAD normal genetic background and a SCAD-deficient background. In three transgenic lines produced on the SCAD-deficient background, recombinant SCAD activity and antigen in liver mitochondria were found up to 7-fold of normal control values. All three lines showed a markedly reduced organic aciduria and fatty liver, which are sensitive indicators of the metabolic abnormality seen in this disease found in children. We found no detrimental effects of high liver SCAD expression in transgenic mice on either background. These studies provide important basic and practical therapeutic information for the potential gene therapy of nuclear-encoded mitochondrial enzyme deficiencies, as well as insights into the mechanisms of the disease.   相似文献   
98.
人乳头瘤病毒11型主要衣壳蛋白L1基因的克隆及序列分析   总被引:4,自引:3,他引:1  
目的 从临床尖锐湿疣标本克隆人乳头瘤病毒(HPV)11型主要衣壳蛋白L1基因,进行序列测定及序列分析比较,以为研究该临床病毒株的免疫原性及流赞美同学奠定基础。方法 以临床尖锐湿疣标本总DNA为模板,用L1基因保守区简并引物以PCR方法分段扩增衣壳蛋白L1基因在部,重组入pGEM-3zf(-)质粒载体,以双脱氧法双向测定插入片段序列,拼接出L1基因序列,通过BLAST2.0与已报道序列进行比较。结果 从西安地区一尖锐湿疣临床标本克隆到的一株HPV11型L1蛋白编码序列与一文献报道大部分相同,但有些位点有点突变,结论 构建的pGEM-3zf(-)重组质粒为进一步通过杂交、体内分段表达等手段研究研究该株病毒L1蛋白的免疫学和流行病学性质创造了条件。  相似文献   
99.
100.

Background  

Disrupted cholesterol regulation leading to increased circulating and membrane cholesterol levels is implicated in many age-related chronic diseases such as cardiovascular disease (CVD), Alzheimer's disease (AD), and cancer. In vitro and ex vivo cellular plasmalogen deficiency models have been shown to exhibit impaired intra- and extra-cellular processing of cholesterol. Furthermore, depleted brain plasmalogens have been implicated in AD and serum plasmalogen deficiencies have been linked to AD, CVD, and cancer.  相似文献   
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