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61.
BACKGROUND: Tenascin-C (Tn-C) is the most studied member of a family comprising large oligomeric glycoproteins in the extracellular matrix. The function of Tn-C still is unclear, and the levels of Tn-C in human wound fluid have not been studied. METHODS: The participants in this study were 24 patients referred for elective major gastrointestinal surgery. Concentrations of Tn-C and procollagen propeptides type 1 and type 3 in serum and wound fluid were measured after surgery. RESULTS: In wound fluid, Tn-C was present on postoperative day 1, and the concentration increased from day 5 up to day 7. CONCLUSIONS: The concentration of Tn-C increases postoperatively in wound fluid. The concentration of Tn-C in wound fluid is markedly higher than that of serum. The differences in expression between Tn-C and the procollagen propeptides may reflect different tasks of these extracellular matrix proteins.  相似文献   
62.
Despite great interspecies differences in adult 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) sensitivity, the toxic potency of TCDD is similar across species in fetal mortality. Han/Wistar (Kuopio; H/W) rats are exceptionally resistant to acute toxicity of TCDD, but show sensitivity to embryotoxicity and teratogenicity. The resistance of adult H/W rats to acute TCDD toxicity is based on a point mutation in the transactivation domain of the aryl hydrocarbon receptor (AHR) and to an unknown gene “B”. This study investigated the time course of postnatal development of resistance to TCDD and the significance of genotypic variation in resistance development. H/W, line A (a new line with the H/W-type mutated AHR), and line B rats (a line with normal AHR but moderately resistant because of gene “B”) were exposed to a single dose of TCDD 2-56 days after birth. H/W and line A rats received 1000 μg/kg; male and female B rats received 200 and 100 μg/kg, respectively. Survival was monitored for 42 days. Interestingly, although TCDD ceased growth and weight gain in all TCDD groups, the younger dosed animals did not seem to reach the body weight of the older dosed animals even in 100 days. The survival results after 42 days showed that line A rats are fairly resistant to TCDD immediately after birth, and their full TCDD resistance develops during the first week of life. The moderate resistance of line B rats develops approximately at the time of weaning. This difference in the time course of resistance development suggests that there are basic differences in pathways mediating resistance in lines A and B rats.  相似文献   
63.
CHEK2 1100delC is not a risk factor for male breast cancer population   总被引:4,自引:0,他引:4  
Genetic risk factors for male breast cancer (MBC) are poorly understood. High penetrance genes such as BRCA1 or BRCA2 account for only a small proportion of the disease. A 1100delC mutation in CHEK2 (previously known as CHK2), a cell-cycle checkpoint kinase, has been implicated in predisposition of Li-Fraumeni syndrome (LFS) and breast cancer in families suggestive of LFS. This 1100delC mutation has also been shown to confer a 2-fold increase of breast cancer risk in women and a 10-fold increase of risk in men. It was estimated to account for 1% of breast cancers in women and as much as 9% of breast cancers in men at the population level based on analysis of breast cancer families without BRCA1 or BRCA2 mutations. We wanted to evaluate the significance of CHEK2 1100delC in predisposition to MBC by assessing its frequency in a population-based material of 114 Finnish MBC patients. Two patients (1.8%) carried the 1100delC mutation. The mutation frequency among MBC cases was similar to that seen in population controls (26/1885, 1.4%). Our results indicate that CHEK2 1100delC variant does not substantially increase the risk of male breast cancer at the population level. We cannot exclude the fact that a small fraction of hereditary, family-positive male breast cancers could be attributable to CHEK2 mutations.  相似文献   
64.
BACKGROUND: The changes in the activity of a number of plasma markers of coagulation and fibrinolysis have previously been studied in patients with ischemic stroke, with conflicting results. We aimed to find out the changes in the activities of a wide array of markers of the coagulation and the fibrinolytic system of mildly or moderately affected first-ever ischemic stroke patients. METHODS: In a prospective, longitudinal, case-control study, we studied plasma plasminogen activator inhibitor type-1 (PAI-1) activity, tissue-type plasminogen activator antigen (t-PA:Ag), d-dimer, prothrombin fragment 1+2 (F 1+2), and thrombin-antithrombin III complex (TAT) levels in 55 consecutive patients on admission, 1 week, 1 month, and 3 months after an ischemic stroke. Sex- and age-matched controls were studied once. All patients underwent blood sampling at each study time point; comprehensive stroke risk factors were recorded, and the etiology of the ischemic stroke was determined. All patients were contacted 3 years later for possible recurrent ischemic events. RESULTS: PAI-1 activity was increased in the acute phase and at 3 months, D-dimer levels were significantly higher at 1 week and 1 month after stroke, whereas t-PA:Ag, TAT and F 1+2 levels remained stable during the whole study period. CONCLUSIONS: The changes of the fibrinolytic and coagulation system activity in the patients with mild or moderate ischemic stroke appeared minor compared with the results of previous studies, which included more severely ill patients.  相似文献   
65.
Allergic disease (AD), including atopic eczema, asthma, allergic rhinitis, and food allergy, is characterized by an imbalance between cytokines produced by distinct T-helper cell subtypes. Whether this imbalance can be transferred from mother to breast milk remains to be established. The objective was to investigate the concentrations and interactions of nutritional and inflammatory factors in breast milk. Breast milk samples were collected from mothers with AD (n = 43) and without AD (n = 51). The concentrations of transforming growth factor (TGF)-beta2, tumor necrosis factor-alpha, IL-4, IL-10, prostaglandin E2, and cysteinyl leukotrienes were measured by immunoassays and fatty acid composition by gas chromatography. Mothers with AD had a lower concentration of TGF-beta2 in breast milk [median (interquartile range), 420 (278-701) ng/L] compared with those without AD [539 (378-1108) ng/L; p = 0.003], whereas other cytokines, prostaglandin E2, and cysteinyl leukotriene concentrations or fatty acid composition were not significantly different between the groups. The breast milk inflammatory factors and fatty acid composition were shown to be related. A positive association was observed between TGF-beta2 and the proportion of polyunsaturated fatty acids (p = 0.038) and a negative association between TGF-beta2 and the proportion of saturated fatty acids (p = 0.029) in breast milk. The reduced TGF-beta2 concentration in the breast milk of mothers with AD may interfere with the development of the mucosal immune system of the breast-fed infant. The observed associations between nutritional and inflammatory factors in breast milk suggest that it may be possible to influence the immunologic properties of breast milk by dietary intervention of the mother.  相似文献   
66.
Garvin S  Dabrosin C 《Cancer research》2003,63(24):8742-8748
Vascular endothelial growth factor (VEGF) is considered a key mediator of tumor angiogenesis, including neovascularization in human breast cancer. High tissue VEGF levels appear to correlate with poor prognosis and decreased overall survival in node-positive and node-negative breast cancer patients. Hormonal regulation of VEGF expression has been demonstrated, and some reports indicate that tamoxifen, a partial estrogen receptor agonist, increases VEGF mRNA in breast cancer cells. These results appear to contradict the efficacy of tamoxifen as an adjuvant for estrogen-dependent breast cancer, yet clinical data show that tamoxifen prevents metastasis and increases overall survival. In this study, we confirmed previous studies showing that intracellular levels of VEGF in vitro increased in response to tamoxifen to levels similar to those observed after estrogen treatment. To further study hormonal effects on the release of VEGF, we used microdialysis to sample the extracellular space, where VEGF is biologically active, in solid tumors in situ. We show for the first time that tamoxifen decreased extracellular VEGF in vivo in solid MCF-7 tumors in nude mice. These in vivo findings were confirmed in vitro where extracellular VEGF in the cell culture medium was decreased significantly by tamoxifen treatment. Furthermore, we illustrate that microdialysis is a viable method that may be applied in human breast tissue to detect soluble VEGF in situ released by the tumor.  相似文献   
67.
BACKGROUND, AIMS: There are biological associations between diabetes control and oral infections. We have also found psychological associations between diabetes self-care and oral health behavior. The aim of this study was to evaluate whether self-esteem can determine diabetes adherence and oral health behavior, both of with require daily, persistent self-care. METHOD: Cross-sectional data on 149 IDDM patients was collected by means of a quantitative self-completed questionnaire. RESULTS: High self-esteem was found to relate to good adherence with exercise regimens (p=0.005) and adjustment of insulin doses (p=0.040). These associations were also found when standardized for socio-demographic variables and HbA1c-level. In the dental sphere, logistic regression analysis showed an association between self-esteem and frequency of tooth brushing. CONCLUSIONS: It can be concluded that self-esteem may be a common psychological factor influencing diabetes and dental self-care. Strengthening patients' self-esteem could help patients to maintain daily self-care.  相似文献   
68.
OBJECTIVE: To assess the influence of central and peripheral neurological diseases on the incidence of accidental falls of the aged. DESIGN: 1. Case-control study with cross-section at two years and 2. prospective study in a follow-up up to seven years thereafter. SETTING: Sample of a population study including all 589 inhabitants older than 70 years in three rural communities. PARTICIPANTS: 44 subjects with recurrent falls during two years' follow-up and 41 age and sex matched controls. MEASURES: Neurological diseases and evaluation, other diseases, and incidence of falls during the seven years' follow-up after the cross-section. RESULTS: Compared with the controls the fallers had more often multiple vascular lesions of the brain, extrapyramidal symptoms and signs as well as lumbar nerve root lesions. In the follow-up, cerebrovascular disease, especially with multiple lesions and residual signs of pyramidal tract lesion, Parkinson's disease, rigidity and hypokinesia were associated with increases risk of falling. In multivariate analysis signs of pyramidal tract lesion, rigidity and prior falls were predictors of falls. An increase in the incidence of falls was also associated with vascular lesion of the cerebellum, cerebral white matter hypodensity and cortical atrophy visible on CT. CONCLUSIONS: High incidence of falls was associated with chronic central nervous system diseases. Lumbar root lesions were more common among the fallers but did not increase the incidence of falls in the follow-up.Neurological diseases and evaluation, other diseases, and incidence of falls during the seven years' follow-up after the cross-section.Compared with the controls the fallers had more often multiple vascular lesions of the brain, extrapyramidal symptoms and signs as well as lumbar nerve root lesions. In the follow-up, cerebrovascular disease, especially with multiple lesions and residual signs of pyramidal tract lesion, Parkinson's disease, rigidity and hypokinesia were associated with increased risk of falling. In multivariate analysis signs of pyramidal tract lesion, rigidity, and prior falls were predictors of falls. An increase in the incidence of falls was also associated with vascular lesion of the cerebellum, cerebral white matter hypodensity and cortical atrophy visible on CT.  相似文献   
69.
70.
We have screened for germline TP53 mutations in Finnish BRCA1 and BRCA2 mutation-negative families. This study represents the largest survey of the entire protein-encoding portion of TP53, and indicates that mutations are only found at conserved domains in breast cancer families also meeting the criteria for Li-Fraumeni/Li-Fraumeni-like syndrome, explaining only a very small additional fraction of the hereditary breast cancer cases.  相似文献   
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