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51.
Objective. Unexplained fatigue syndromes are multidimensional phenomena that involve a constellation of symptoms. This paper explores whether typical relationship patterns are associated with self‐reported and clinically rated fatigue symptoms in chronically fatigued patients. Method. Relationship patterns were assessed by means of the core conflictual relationship theme (CCRT) method. This method examines transference patterns, and was applied to interview data collected from chronically fatigued patients (N=30). Chronic fatigue was assessed by means of a self‐report questionnaire and was also rated clinically. Results. Both self‐reported and clinically rated fatigue correlated with relationship themes. The intensity of fatigue related to the perception of others as not respecting and as negatively interfering. The typical reaction of the self to relationships consists of feeling disrespected, anger, passivity, and reduced feelings of self‐consistency. Conclusion. Patients' perception of interpersonal relationships as distressing may be pivotal in understanding these results. Implications for clinical intervention and future research are indicated.  相似文献   
52.
The dietary intake of polychlorinated dibenzo-p-dioxins (PCDDs), dibenzofurans (PCDFs) and biphenyls (PCBs) in terms of toxic equivalents (TEQs) was investigated in Swedish children and young adults. Exposure was estimated from concentration data of six groups of individual food commodities (meat, fish, dairy products, egg, edible fats and other foodstuff) combined with food intake data from a 7-day record book obtained from 670 individuals aged 1–24 years. The results showed that Swedish boys and girls, up to the age of ten, had a median TEQ intake that exceeded the tolerable daily intake (TDI) of 2 pg TEQ/kg body weight. Children exceeding the TDI varied from almost all individuals among the youngest children to about 20% among young men and women. Dairy and fish products were the main sources of exposure for the average child, accounting for 59% of the total TEQ intake. The individuals most highly exposed were, on the other hand, characterized by a high consumption of fish. Since children constitute a vulnerable group, results obtained from the present study show that it is essential to perform age specific dietary intake assessments of pollutants and more carefully consider sensitive and/or highly exposed groups in the population in the risk management processes.  相似文献   
53.
More than 500 colorectal tumors with clonal chromosomal abnormalities have been reported. Although the pattern of aberrations is nonrandom, no specific primary or secondary karyotypic abnormality has been identified. Also, the chronological order in which the aberrations appear during disease progression is not well known. One reason why our understanding of the cytogenetic evolution is unclear is the high degree of karyotypic complexity seen in these tumors. To overcome some of these difficulties we have previously used several statistical methods that allow identification and interpretation of karyotypic pathways as well as establishment of a temporal order of appearance of the imbalances. These methods were applied on 531 colorectal tumor karyotypes. By using a resampling strategy, 1p-, +7, 7q-, and +12p were identified as early events. Two major and two minor cytogenetic pathways were identified by means of principal component analysis. The two major pathways were initiated with 1p- and +7, and the minor pathways were initiated with +12p and 7q-. The +7/+12p tumors were found to be hyperdiploid, whereas those with 1p-/7q- were pseudodiploid. We also show that the adenoma-carcinoma transition in the 1p- pathway is strongly linked to karyoytypic evolution, whereas the +7 pathway is not, and that the cytogenetic pathways are separated at both early and late stages.  相似文献   
54.
The European Journal of Health Economics -  相似文献   
55.
The COMT val158met polymorphism is associated with peak BMD in men.   总被引:2,自引:0,他引:2  
The associations between the functional val158met polymorphism of the estrogen-degrading COMT enzyme and skeletal properties in young men were investigated. BMD was associated with COMT genotype. INTRODUCTION: Peak BMD is an important predictor of future risk of osteoporosis, and it is to a large extent determined by genetic factors. Estrogens are involved in the accretion of bone mass during puberty. Catechol-O-methyltransferase (COMT) is involved in the degradation of estrogens. There is a functional polymorphism in the COMT gene (val158met), resulting in a 60-75% difference in enzyme activity between the val (high activity [H]) and met (low activity [L]) variants. The aim of this cross-sectional study was to investigate the associations between this polymorphism and peak BMD in young men. MATERIALS AND METHODS: A total of 458 healthy men (mean age, 19 +/- 0.6 years) were genotyped and classified as COMT(LL), COMT(HL), or COMT(HH). Areal BMD (aBMD) was measured by DXA. Cortical and trabecular volumetric BMD (vBMD) were measured by pQCT. The associations between COMT genotype and skeletal phenotypes were determined. RESULTS AND CONCLUSIONS: Regression models using physical activity, height, weight, age, and COMT genotype as covariates showed that COMT genotype was an independent predictor of aBMD in the total body and in all femur locations investigated, but not in the spine. The values for COMT(HL) and COMT(HH) were very similar, and therefore, they were pooled into one group. aBMD at Ward's triangle, trochanter, and total femur were 4.9%, 4.5%, and 3.7% lower, respectively, in the COMT(LL) than in the COMT(HL/HH) group (p < 0.01). pQCT analyses showed that COMT genotype was an independent predictor of trabecular vBMD of the tibia, radius, and fibula. Trabecular vBMD of the radius and fibula in COMT(LL) was 5.3% and 7.4% lower, respectively, than that of the combined COMT(HL/HH) group. COMT genotype was associated with cortical vBMD but not with cortical cross-sectional area in the tibia. These findings show that the COMT polymorphism is associated with BMD in young adult men.  相似文献   
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BACKGROUND: Low back pain (LBP) is a common cause of lost work days and disability. In 2001, expenditure for back pain represented 11% of the total costs for short-term sick leave in Sweden, and about 13% of all early retirement pensions were granted for back problems, of which LBP is the most important symptom. The magnitude of LBP as a health problem justifies a closer look at its burden of illness to society. MATERIALS AND METHODS: We assessed the costs of LBP to society in Sweden in 2001. The study was conducted in a cost-of-illness framework, measuring both the direct costs of providing health care to LBP patients, and the indirect costs as the value of the production that is lost because people are too ill to work. The costs were estimated by a prevalence and top-down approach. RESULTS: The total cost of LBP was 1860 million EUR in Sweden in 2001. The indirect costs due to lost productivity accounted for 84% of the total cost. INTERPRETATION: The cost of illness due to low back pain was substantial, but does not appear to have risen during the last 10-15 years.  相似文献   
59.
Maternal administration of folic acid diminishes the risk of neural tube defects (NTDs) in offspring, but whether folic acid exerts a similar effect in diabetic pregnancy is unknown. The aim was to investigate whether maldevelopment in rat embryos caused by exposure to diabetes in vivo or high-glucose concentrations in vitro is affected by subcutaneous administration of folic acid to the pregnant mother or by adding the compound to the culture medium, respectively. Exposure of embryos to maternal diabetes in vivo or 30 mmol/l glucose in vitro yielded an increased malformation rate (71 and 88% NTD, respectively) and lowered somite number and crown-rump length compared with control embryos. When we injected folic acid into the diabetic pregnant rat, or added 2 mmol/l folic acid to the culture medium with high glucose, the embryonic parameters improved (3 and 5% NTD, respectively). The present work shows that administration of folic acid can diminish diabetes-induced maldevelopment. This suggests that folic acid supplementation may have a role in the prevention of malformations in diabetic pregnancy.  相似文献   
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