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目的探讨环境致癌物苯并(a)芘代谢物反式二羟环氧苯并芘(BPDE)对人支气管上皮细胞HER2/neu基因表达的影响。方法利用半定量RT-PCR、SYBR GreenI实时定量RT-PCR(QRT-PCR)、Western blot及免疫细胞化学方法分别检测经2.0μmol/L反式BPDE诱发人支气管上皮细胞恶性转化细胞(16HBE-T)与对照DMSO溶剂组未恶性转化细胞(16HBE-N)之间HER2/neu基因mRNA和蛋白表达水平的差异,及两组细胞内HER2/neu蛋白表达定位分析。结果经几种不同方法检测反式BPDE恶性转化人支气管上皮细胞中HER2/neu基因mRNA和蛋白水平都比对照溶剂组细胞(16HBE-N)表达显著升高(P<0.05)。HER2/neu蛋白定位在胞膜。结论反式BPDE诱发人支气管上皮细胞恶性转化存在HER2/neu表达增高,其可能与原癌基因HER2/neu被激活作用有关。  相似文献   
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Acrylamide is a component of roasted coffee and certain baked and fried carbohydrate-rich foods prepared at high temperatures. We have assessed the carcinogenicity of acrylamide in male and female B6C3F1 mice and F344/N rats administered 0, 0.0875, 0.175, 0.35, or 0.70 mM acrylamide in the drinking water ad libitum for 2 years. Acrylamide caused significant dose-related decreasing trends in the body weights of F344/N rats. Acrylamide administration resulted in significant dose-related decreasing trends in survival in both sexes of B6C3F1 mice and in female F344/N rats. Histopathological analyses indicated significant dose-related increases in Harderian gland and lung tumors in male and female B6C3F1 mice. Male B6C3F1 mice also had a significantly increased incidence of forestomach tumors, while female B6C3F1 mice had significant dose-related increases in mammary gland, ovary, and skin tumors. In male and female F344/N rats, there were significant increases in thyroid tumors. Male F344/N rats also had significant dose-related increases in testes, heart, and pancreas tumors, while female F344 rats demonstrated significant increases in clitoral gland, mammary gland, oral cavity, and skin tumors. These results, combined with previous mechanistic studies, provide strong support for the concept that acrylamide is activated to a carcinogen through metabolism to glycidamide.  相似文献   
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Type 2 diabetes(T2D)has become a major public health threat across the globe.It has been widely acknowledged that diet plays an important role in the development and management of T2D.Phytoestrogens are polyphenols that are structurally similar to endogenous estrogen and have weak estrogenic properties.Emerging evidence from pre-clinical models has suggested that phytoestrogens may have anti-diabetic function via both estrogendependent and estrogen-independent pathways.In the current review,we have summarized the evidence linking two major types of phytoestrogens,isoflavones and lignans,and T2D from epidemiological studies and clinical trials.The cross-sectional and prospective cohort studies have reported inconsistent results,which may due to the large variations in different populations and measurement errors in dietary intakes.Long-term intervention studies using isoflavone supplements have reported potential beneficial effects on glycemic parameters in postmenopausal women,while results from short-term smallsize clinical trials are conflicting.Taken together,the current evidence from different study designs is complex and inconsistent.Although the widespread use of phytoestrogens could not be recommended yet,habitual consumption of phytoestrogens,particularly their intact food sources like soy and whole flaxseed,could be considered as a component of overall healthy dietary pattern for prevention and management of T2D.  相似文献   
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BackgroundThere is a paucity regarding interventions in general, and especially internet-delivered treatment options, for adolescents and young adults with autism spectrum disorder (ASD), despite the group´s capacity and willingness to utilize computer-mediated communication. This open feasibility study evaluated the new internet-delivered, psychoeducational intervention, SCOPE (Spectrum COmputerized PsychoEducation), for adolescents and young adults aged 16–25 years with ASD in the normative IQ range.MethodThe participation in SCOPE was facilitated by weekly contacts with disability service professionals (trained coaches) and the intervention consisted of eight ASD-themed modules. In an open feasibility study we evaluated treatment completion, treatment credibility and satisfaction, as well as preliminary efficacy. We assessed feasibility in an outpatient disability services context, regarding both participants’ and coaches’ experiences.ResultsTwenty-three out of the 29 included participants (79%) completed the intervention. The participants’ experience of treatment credibility was increased during the SCOPE web course and the overall satisfaction with the treatment was high. The coaches reported high treatment credibility and good clinical feasibility of the internet-based delivered intervention. The participants’ knowledge of ASD increased significantly from pre-intervention to post-intervention. The increased knowledge of ASD was not associated with negative effects on psychological well-being.ConclusionsOur results suggest that the internet-delivered psychoeducational intervention SCOPE is a feasible intervention and could contribute to youth’s sense of empowerment through increased knowledge of ASD and themselves. An ongoing randomized controlled study will generate further evidence concerning the SCOPE intervention.  相似文献   
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Home literacy environment (HLE) is one of most important modifiable risk factors to dyslexia. With the development in technology, we include the electronic devices usage at home, such as computers and televisions, to the definition of HLE and investigate its impact on dyslexia based on the on-going project of Tongji's Reading Environment and Dyslexia Study. The data include 5063 children, primary school students (grade 3–grade 6), from a middle-sized city in China. We apply the principal component analysis (PCA) to reduce the large dimension of variables in HLE, and find the first three components, denoted as PC1, PC2 and PC3, can explain 95.45% of HLE information. PC1 and PC2 demonstrate strong positive association with ‘total time spending on electronic devices’ and ‘literacy-related activity’, respectively. PC3 demonstrates strong negative association with ‘restrictions on using electronic devices’. From the generalized linear model, we find that PC1 significantly increases the risk of dyslexia (OR = 1.043, 95% CI: 1.018–1.070), while PC2 significantly decreases the risk of dyslexia (OR = 0.839, 95% CI: 0.795–0.886). Therefore, reducing the total time spending on electronic devices and increasing the literacy-related activity would be the potential protective factors for dyslexic children in China.  相似文献   
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ObjectivesThe purpose of this study was to examine the association between screen time in adolescence and depressive symptoms in young adulthood in a population-based cohort study of Danish adolescents.MethodsData were from a cohort of adolescents who were followed-up in young adulthood for a period of up to 12 years (1997–2010, mean 8.8 years, n = 435). Information on television viewing, computer use, total screen time and other determinants of depression were obtained in adolescence. Depressive symptoms were obtained in young adulthood using the Major Depression Inventory (MDI) and classified as mild, moderate or severe depression. Mixed regression models were used to examine the associations, with adjustment for major confounders.ResultsIn multivariable adjusted analyses, each additional hour/day spent watching television or screen viewing in adolescence was associated with 1.36 (95% CI 0.73–1.98) and 1.05 (95% CI 0.50–1.60), respectively, greater MDI depression summary score in young adulthood (p < 0.001). In logistic regression models, each additional hour/day spent watching television or screen viewing was associated with 1.64 (95% CI 1.18–2.27) and 1.58 (95% CI 1.18–2.12), respectively, greater odds of prevalent depression in young adulthood, and dose–response relationships were indicated. Additional adjustment for either cardiorespiratory fitness or BMI did not materially change the results. No significant associations were observed between adolescent computer use and depressive symptoms in young adulthood.ConclusionsLimiting screen time, particularly television viewing, during adolescence may be important for preventing depression in young adulthood.  相似文献   
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Bisphenol A (BPA), one of the high‐volume chemicals worldwide, has a core structure resembling that of natural estradiol. Recent evidence has demonstrated that exposure to BPA has a relationship with the risk of cancer. The objective of our study is to investigate the mechanisms underlying the pro‐angiogenic effects of BPA. We demonstrated that BPA markedly induces endothelial cell proliferation, migration and tube formation by activating endothelial nitric oxide synthase. BPA‐induced nitric oxide generation appeared to be associated with the X‐linked inhibitor of apoptosis protein (XIAP), which competes with endothelial nitric oxide synthase for caveolin‐1. BPA was shown to exert its pro‐angiogenic effect by upregulating XIAP expression via G protein‐coupled estrogen receptor (ER) activation but not via ERα or ERβ. Our data suggest that 100 nM BPA promote angiogenesis in a G protein‐coupled ER‐dependent genomic pathway, and provide a novel insight into the potential role of XIAP in mediating the pro‐angiogenic effects of BPA in endothelial cells. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
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