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In cattle and other ruminants, infection with the intracellular pathogen Mycobacterium avium subsp. paratuberculosis results in a granulomatous enteritis (Johne's disease) that is often fatal. The key features of host immunity to M. avium subsp. paratuberculosis infection include an appropriate early proinflammatory and cytotoxic response (Th1-like) that eventually gives way to a predominant antibody-based response (Th2-like). Clinical disease symptoms often appear subsequent to waning of the Th1-like immune response. Understanding why this shift in the immune response occurs and the underlying molecular mechanisms involved is critical to future control measures and diagnosis. Previous studies have suggested that M. avium subsp. paratuberculosis may suppress gene expression in peripheral blood mononuclear cells (PBMCs) from infected cows, despite a continued inflammatory reaction at sites of infection. In the present study, we tested the hypothesis that exposure to M. avium subsp. paratuberculosis suppresses a proinflammatory gene expression pattern in PBMCs from infected cows. To do this, we examined expression of genes encoding interleukin-1alpha (IL-1alpha), IL-2, IL-4, IL-5, IL-6, IL-8, IL-10, IL-12p35, IL-16, and IL-18, as well as genes encoding gamma interferon (IFN-gamma), transforming growth factor beta (TGF-beta), and tumor necrosis factor alpha (TNF-alpha), in PBMCs, intestinal lesions, and mesenteric lymph nodes of cattle naturally infected with M. avium subsp. paratuberculosis. Cytokine gene expression in these cells and tissues was compared to expression in similar cells and tissues from control uninfected cattle. Our comprehensive results demonstrate that for most cytokine genes, including the genes encoding IFN-gamma, TGF-beta, TNF-alpha, IL-1alpha, IL-4, IL-6, IL-8, and IL-12p35, differential expression in PBMCs from infected and control cattle did not require stimulation with M. avium subsp. paratuberculosis. In fact, stimulation with M. avium subsp. paratuberculosis tended to reduce the differential expression observed in infected and uninfected cows for genes encoding IFN-gamma, IL-1alpha, and IL-6. Only IL-10 gene expression was consistently enhanced by M. avium subsp. paratuberculosis stimulation of PBMCs from subclinically infected cattle. In ileal tissues from M. avium subsp. paratuberculosis-infected cattle, expression of the genes encoding IFN-gamma, TGF-beta, IL-5, and IL-8 was greater than the expression in comparable tissues from control uninfected cattle, while expression of the gene encoding IL-16 was lower in tissues from infected cattle than in control tissues. Mesenteric lymph nodes draining sites of M. avium subsp. paratuberculosis infection expressed higher levels of IL-1alpha, IL-8, IL-2, and IL-10 mRNA than similar tissues from control uninfected cattle expressed. In contrast, the genes encoding TGF-beta and IL-16 were expressed at lower levels in lymph nodes from infected cattle than in tissues from uninfected cattle. Taken together, our results suggest that cells or other mechanisms capable of limiting proinflammatory responses to M. avium subsp. paratuberculosis develop in infected cattle and that a likely place for development and expansion of these cell populations is the mesenteric lymph nodes draining sites of infection.  相似文献   
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Objective: Motivation is suggested as an important factor in pediatric motor rehabilitation. Therefore, we reviewed the existing evidence of (motivational) motor rehabilitation paradigms, and how motivation influences rehabilitation outcome using self-determination theory as conceptual framework. Methods: PubMed and Web-of-Science databases were systematically searched until June 2015. Data were independently extracted and critiqued for quality by three authors. Studies reporting motivational aspects were included. Most studies examined new technology (e.g., virtual reality [VR]). Results: Out of 479 records, three RCT, six case-control, and six non-comparative studies were included with mixed quality. Motivation was rarely reported. Training individualization to the child’s capabilities with more variety seemed promising to increase motivation. Motivation increased when the exercises seemed helpful for daily activities. Conclusions: Motivation in pediatric rehabilitation should be comprehensively assessed within a theoretical framework as there are indications that motivated children have better rehabilitation outcomes, depending on the aspect of motivation.  相似文献   
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Background.?Tuberculosis-immune reconstitution inflammatory syndrome (TB-IRIS) in patients coinfected with human immunodeficiency virus (HIV) and tuberculosis starting antiretroviral therapy (ART) is associated with hypercytokinemia. As adjunctive corticosteroid therapy and vitamin D have immunomodulatory properties, we investigated the relationship between cytokine/chemokine profiles, corticosteroid use, and vitamin D deficiency in TB-IRIS patients. Methods.?Plasma from 39 TB-IRIS and 42 non-IRIS patients was collected during a prospective study of HIV-associated tuberculosis patients starting ART. In total, 26% of patients received corticosteroid (CTC) therapy pre-ART for severe tuberculosis. Concentrations of total 25-hydroxyvitamin D (25(OH)D) and 14 cytokines/chemokines were determined at ART initiation and 2 weeks later. Results.?Patients prescribed concurrent CTC had lower interferon γ (IFN-γ), IP-10, tumor necrosis factor (TNF), interleukin (IL)-6, IL-8, IL-10, IL-12p40, and IL-18 pre-ART (P?≤?.02). TB-IRIS presented at 12 days (median) of ART, irrespective of CTC use. In patients who developed TB-IRIS (not on CTC) IL-6, IL-8, IL-12p40, IL-18, IP-10, and TNF increased during 2 weeks (P?≤?.04) of ART. Vitamin D deficiency (total 25(OH)D <75?nmol/L) was highly prevalent (89%) at baseline. Although vitamin D deficiency at either baseline or 2 weeks was not associated with TB-IRIS, in those not on CTC the median 25(OH)D decreased during 2 weeks (P?=?.004) of ART. Severe vitamin D deficiency (total 25(OH)D <25?nmol/L) was associated with higher baseline TNF, IL-6, and IL-8 irrespective of IRIS status. Conclusions.?CTC modifies the inflammatory profile of those who develop TB-IRIS. The association between severe vitamin D deficiency and elevated proinflammatory cytokines support a study of vitamin D supplementation in HIV-TB co-infected patients starting ART.  相似文献   
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Objectives To synthesize the evidence on the psychometrics functional capacity evaluation (FCE) methods. Methods A systematic literature search in nine databases. The resulting articles were screened based on predefined in- and exclusion criteria. Two reviewers independently performed this screening. Included studies were appraised based on their methodological quality. Results The search resulted in 20 eligible studies about nine different FCE methods. The Baltimore Therapeutic Equipment work simulator showed a moderate predictive validity. The Ergo-Kit (EK) showed moderate variability and high inter- and intra-rater reliability. Low discriminative abilities and high convergent validity were found for the EK. Concurrent validity of the EK and the ERGOS Work Simulator was low to moderate. Moderate to high test–retest, inter- and intra-reliability was found in the Isernhagen Work-Systems (IWS) FCE. The predictive validity of the IWS was low. The physical work performance evaluation (PWPE) showed moderate test–retest reliability and moderate to high inter-rater reliability. Low internal and external responsiveness were found for the PWPE, predictive validity was high. The predictive validity of the short-form FCE was also high but need to be further examined on several psychometric properties. Low discriminative and convergent validity were found for the work disability functional assessment battery. The WorkHab showed moderate to high test–retest, inter- and intra-rater reliability. Conclusion Well-known FCE methods have been rigorously studied, but some of the research indicates weaknesses in their reliability and validity. Future research should address how these weaknesses can be overcome.  相似文献   
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Chemotherapy and radiation therapy (RT) are standard therapeutic modalities for patients with cancer, including breast cancer. Historic studies examining tissue and cellular responses to RT have predominantly focused on damage caused to proliferating malignant cells leading to their death. However, there is increasing evidence that RT also leads to significant alterations in the tumor microenvironment, particularly with respect to effects on immune cells infiltrating tumors. This review focuses on tumor-associated immune cell responses following RT and discusses how immune responses may be modified to enhance durability and efficacy of RT.  相似文献   
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Angiogenesis, extracellular matrix remodeling and cell migration are associated with cancer progression and involve at least, the plasminogen activating system and its main physiological inhibitor, the plasminogen activator inhibitor‐1 (PAI‐1). Considering the recognized importance of PAI‐1 in the regulation of tumor angiogenesis and invasion in murine models of skin tumor transplantation, we explored the functional significance of PAI‐1 during early stages of neoplastic progression in the transgenic mouse model of multistage epithelial carcinogenesis (K14‐HPV16 mice). We have studied the effect of genetic deletion of PAI‐1 on inflammation, angiogenesis, lymphangiogenesis and tumor progression. In this model, PAI‐1 deficiency neither impaired keratinocyte hyperproliferation or tumor development nor affected the infiltration of inflammatory cells and development of angiogenic or lymphangiogenic vasculature. We are reporting evidence for concomitant lymphangiogenic and angiogenic switches independent to PAI‐1 status. Taken together, these data indicate that PAI‐1 is not rate limiting for neoplastic progression and vascularization during premalignant progression, or that there is a functional redundancy between PAI‐1 and other tumor regulators, masking the effect of PAI‐1 deficiency in this long‐term model of multistage epithelial carcinogenesis.  相似文献   
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The role of the extracellular matrix (ECM) in the tumor microenvironment is not limited to being a barrier against tumor invasion. The ECM is a reservoir of cell binding proteins and growth factors that affect tumor cell behavior. It is also substantially modified by proteases produced by tumor cells or stroma cells. As a result of the activity of these proteases, cell-cell and cell-ECM interactions are altered, new biologically active ECM molecules are generated, and the bioavailability and activity of many growth factors, growth factor receptors, and cytokines are modified. ECM-degrading proteases also play a critical role in angiogenesis, where they can act as positive as well as negative regulators of endothelial cell proliferation and vascular morphogenesis. This review article summarizes some of the most relevant findings made over the recent years that were discussed at a workshop organized by the Path B Study Section of the National Institutes of Health in October 2002.  相似文献   
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