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TRACP, a marker of osteoclasts, is also expressed by cells of the immune system. We identified a novel function for TRACP in the dendritic cell. DCs from TRACP knockout mice have impaired maturation and trigger reduced Th1 responses in vivo. We postulate that TRACP has an important role in the presentation of antigens to T cells. INTRODUCTION: TRACP is highly expressed by osteoclasts, activated macrophages, and dendritic cells (DCs). Knockout mice lacking TRACP have an intrinsic defect in osteoclastic resorption and macrophages that display abnormal immunomodulatory responses and cytokine secretion profiles. Our aim in this study was to investigate the significance of TRACP in the inductive phase of the immune response by examining dendritic cells from TRACP(-/-) mice. MATERIALS AND METHODS: Maturational state and function of leukocyte subsets in mice was assessed by flow cytometry. The ability of the immune system to respond to nonspecific activation and to specific antigen was assessed by delayed type hypersensitivity and the presence of isotype-specific serum antibody in vivo and T-cell proliferation and cytokine production in vitro. RESULTS: The ability of lipopolysaccharide (LPS) to upregulate MHC II and CD80 in DCs from TRACP(-/-) mice was reduced compared with wildtype mice, although production of IL-10 by DCs from TRACP-deficient animals was increased. T- and B-cell responses not involving antigen presentation (anti-CD3, TNP-ficoll) were normal in TRACP(-/-) mice, but responses to T-dependent antigens were impaired. Specifically, TRACP(-/-) mice had defective delayed hypersensitivity responses to picryl chloride and reduced proliferative responses to ovalbumin compared with wildtype mice. In response to ovalbumin, but not anti-CD3, T cells from TRACP(-/-) mice produced less interferon-gamma (IFN-gamma), but there was no difference in IL-4 production: TRACP(-/-) mice also produced less ovalbumin (OVA)-specific IgG2a after immunization. CONCLUSIONS: The finding that DCs from TRACP(-/-) mice have impaired maturation and defective Th1 responses shows that TRACP is important for polarizing responses in na?ve T cells to antigen-presented dendritic cells.  相似文献   
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BackgroundFull-thickness bone resorption around the humeral stem in shoulder arthroplasty is an increasingly recognized phenomenon, but the impact on outcomes remains unclear. This study aims to investigate prevalence of bone resorption in patients with the Zimmer-Biomet Comprehensive reverse shoulder arthroplasty and the impact on the functional outcomes.MethodsA retrospective analysis was carried out on 65 consecutive patients with primary reverse total shoulder arthroplasty using the Comprehensive Shoulder System from 2014 to 2020, with a minimum of 12-month follow-up. The prevalence of humeral bone resorption was graded from 0 to 4, and risk factors for these changes and their impact on functional outcomes were further investigated.ResultsThe majority of patients (75%) were female with an average age of 75 years (53-93), with an overall average follow-up of 26 months (12-60). Bone resorption occurred in 53 patients (82%), and full-thickness bone resorption occurred in only 8 patients (12%). Metaphyseal bone (zones 1 and 7) is mostly at the risk of high-grade resorption. There was no difference in the final Oxford Shoulder Score between patients who had differential resorption grades from 0 to 4 (P = .5742). None of the risk factors from the previous literature including age, sex, indication for surgery, rotator cuff tear and repair, and intramedullary occupation ratio of the implant showed any impact on the rate of resorption.ConclusionFull-thickness humeral bone resorption occurred in approximately 12% of patients when using the Comprehensive reverse shoulder arthroplasty, but it has no impact on the functional outcomes or revision rate in the short-to-medium term.  相似文献   
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The authors report the healthy delivery of the first successful round spermatid injection in Iran. The male was a 40-year-old with nonobstructive azoospermia whose previous testicular biopsy revealed only round spermatids. The wife was a 29-year-old healthy woman.  相似文献   
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The type III deiodinase (D-III) activity in astroglial cells is induced by multiple pathways activated by cAMP, 12-O-tetradecanoylphorbol-13-acetate (TPA), and fibroblast growth factors (FGFs). This study examines the effects of thyroid hormones on D-III activity in astroglial cells with or without induction by these factors. Addition of 10 nM T3 to the culture medium caused a slow increase in D-III activity, which reached a plateau after 48 h. This increase was concentration dependent (maximal response at 10 nM). Doses as low as 0.3 nM caused significant increases in D-III activity. The effect of T3 was reversible. A dose of 10 nM L-T3, D-T3, T4, 3,5,3'-triiodothyroacetic, or 3'-isopropyl-3,5-diiodothyronine produced 5- to 15-fold increases in D-III activity after 48 h. In contrast, 10 nM L-thyronine, 3-monoiodothyronine, 3,3'-diiodothyronine, 3,5-diiodothyronine, and rT3 were without effect. A dose of 10 nM T3 or T4 amplified the D-III activity stimulated by 0.1 microM TPA, 20 ng/ml acidic FGF, or 1 mM 8-bromo-cAMP 3- to 8-fold. Otherwise, T3 rapidly inhibited D-II activity. This inhibition was concentration dependent, with a half-maximal effect around 10 nM. In conclusion, thyroid hormones induce D-III activity and potentiate the D-III activity induced by cAMP, TPA, and FGFs in astroglial cells. These reversible effects together with inhibition of D-II activity may contribute to protect the brain against hyperthyroidism.  相似文献   
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Purpose : MTT (3-(4,5-dimethyl thiazol-2-yl)-2,5-diphenyl tetrazolium bromide) assay is commonly used as a cell proliferation assay. The objective of this study was to evaluate the capability of MTT assay to discriminate between viable and nonviable sperms and compare its efficiency with E&N (eosin and nigrosin) and HOST (hypo-osmotic swelling test). Methods : MTT assay was modified to obtain optimal result for assessment of sperm viability. After standardization of method, MTT, E&N, and HOST were carried out simultaneously on 57 semen samples from patients referring to Isfahan Fertility and Infertility Center. The correlation coefficient between these tests and sperm motility was calculated using the SPSS statistical program. Specificity and sensitivity of each test was also obtained. Results : The optimal conditions for sperm MTT viability assay were 2 h after addition of sperm to MTT in HAM'S F10 + 25 mM HEPES + 10% HSA at 37°C and pH 7.4–7.45. Inter- and intra-assay coefficients of variations were 9 and 7%, respectively. The sensitivity and specificity for sperm MTT viability assay, E&N, and HOST were 97, 98, and 99%, and 100, 100, and 83% respectively. High significant correlations were obtained between sperm MTT viability assay, E&N, HOST and motility. Conclusions : Sperm MTT viability assay can be used as a diagnostic test for discrimination of viable sperms from sperm population.  相似文献   
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Despite attempts to control bovine tuberculosis, the incidence of disease in Great Britain continues to rise. In GB, the European badger (Meles meles) is a reservoir of infection with Mycobacterium bovis. In an effort to improve the serodetection of badger tuberculosis, we examined sera from M. bovis culture-positive and culture-negative badgers for their ability to recognize M. bovis antigens, using a multi-antigen print immunoassay (MAPIA). Depending on the antigens used in the MAPIA, the assay had a sensitivity of 49-59% and a specificity of 84-88% Results from the MAPIA were used to select antigens for the development of a lateral-flow immunoassay. This so-called 'Rapid Test' used 5microl of serum and gave unambiguous results within 10 min. When applied to 178 badger sera, the Rapid Test had a sensitivity of 53% and a specificity of 95%. This represented an improvement over the performance of the existing ELISA Test, which had a sensitivity of 47% and a specificity of 89% on the same sera. This is the first report of a diagnostic test for badger tuberculosis that can be performed alongside the captive animal.  相似文献   
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OBJECTIVE: To examine the relationship between sperm reactive oxygen species (ROS) production and sperm morphology in a group of infertile men and healthy fertile donors. DESIGN: A prospective clinical study. SETTING: Male infertility clinic, Glickman Urological Institute, The Cleveland Clinic Foundation, Cleveland, Ohio, and the Reproductive Medicine Unit, Liverpool Women's Hospital, United Kingdom PATIENT(S): Thirty-nine infertile men and 13 healthy fertile donors (control). INTERVENTION(S): Standard semen analysis, seminal leukocyte concentration, assessment of sperm morphology, and measurement of sperm ROS production. MAIN OUTCOME MEASURE(S): Levels of sperm ROS production, percentages of different sperm morphological abnormalities, and the sperm deformity index (SDI) scores. RESULT(S): A significant negative correlation was observed between sperm ROS production and the proportion of sperm with normal morphology and borderline morphology. Reactive oxygen species production was positively correlated with the proportion of sperm with amorphous heads, damaged acrosomes, midpiece defects, cytoplasmic droplets, tail defects, and SDI scores. Logistic regression analysis identified a two-variable model including SDI and percentage sperm motility, which correctly identified 84% of individuals with high seminal ROS and 85% of individuals with low seminal ROS. The model had an overall accuracy of 85%. CONCLUSION(S): The standard semen analysis to assess sperm motility, sperm morphology, and the SDI scores is a useful tool in identifying infertile men with high seminal ROS in infertility clinics where facilities for measuring levels of seminal ROS are not available.  相似文献   
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