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In order to produce long term lymphoid cell cultures from canine lymphocytes of known histocompatibility antigen specificities, mitogenic responses to staphylococcal protein A (SpA) were examined and compared with those of phytohaemagglutinin (PHA) and concanavalin A (Con A). SpA was found to be the strongest mitogen tested with significant responses to concentrations as low as 31 ng/ml. There was a decrease in responsiveness above optimal mitogen concentrations with SpA and PHA. Peak responses were observed at lower concentrations for longer incubation times. PHA showed a rapid fall off in thymidine uptake below optimal concentrations whereas the SpA dose-response curve was less steep and a shoulder or secondary peak of activity was observed at low SpA concentrations in some cases.Continuous SpA stimulation of lymphocyte cultures resulted in an initial period of cell proliferation followed usually by a second period of cell proliferation around week 7 of culture. To date, viable cell cultures have been maintained for up to 12 weeks in vitro.SpA lymphoblast cultures behave normally in microcytotoxicity tests for serologically defined DLA histocompatibility antigens and remain functional in natural killer (NK) and PHA induced cell mediated cytotoxic reactions against 51Cr-labelled tumour target cells but were not themselves susceptible as target cells for NK activity.  相似文献   
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The VATER/VACTERL association describes the combination of congenital anomalies including vertebral defects, anorectal malformations, cardiac defects, tracheoesophageal fistula with or without esophageal atresia, renal malformations, and limb defects. As mutations in ciliary genes were observed in diseases related to VATER/VACTERL, we performed targeted resequencing of 25 ciliary candidate genes as well as disease‐associated genes (FOXF1, HOXD13, PTEN, ZIC3) in 123 patients with VATER/VACTERL or VATER/VACTERL‐like phenotype. We detected no biallelic mutation in any of the 25 ciliary candidate genes; however, identified an identical, probably disease‐causing ZIC3 missense mutation (p.Gly17Cys) in four patients and a FOXF1 de novo mutation (p.Gly220Cys) in a further patient. In situ hybridization analyses in mouse embryos between E9.5 and E14.5 revealed Zic3 expression in limb and prevertebral structures, and Foxf1 expression in esophageal, tracheal, vertebral, anal, and genital tubercle tissues, hence VATER/VACTERL organ systems. These data provide strong evidence that mutations in ZIC3 or FOXF1 contribute to VATER/VACTERL.  相似文献   
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Stress due to endurance training of striated muscles leads to adaptive changes in the distribution of muscle fiber types (i.e. ratio of type I and type II fibers). Moreover, severe training leads to tissue hypoxia and oxidative stress in muscles. In the current study, we examined the relationship between histological changes and oxidative state in muscles of mastication during the acute adaptation phase to a sustained muscle load. Six domestic pigs received build-ups on the molar teeth in order to induce a sustained load of the muscles of mastication for a duration of four weeks. Afterwards the masseter (M1, M2, M3), medial pterygoid (PM), temporal (TP1, TP2), and geniohyoid muscles (GH) were removed and the fiber type distribution was determined by enzyme histochemistry. Additionally, the tissue content of glutathione and lipid peroxidation (LPO) products were measured. The above treatment led to muscle fiber transformation of type II into type I (M1, M2, TP2, PM) and a decrease of the GSH content (M1, M2 and TP2). The changes in the GSH/GSSG ratio were in accordance with the changes in proportions of muscle fiber types, with the lowest GSH/GSSG ratios in the most stressed muscles of the treated animals. No significant changes in LPO products were found. The decrease of the GSH/GSSG ratio in the most stressed muscles indicates an increased intracellular oxidative stress, which may be caused by tissue hypoxia during the chronic phase of muscle adaptation.  相似文献   
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BACKGROUND.

Breast cancer is the leading cause of cancer‐related deaths in Latinas, chiefly because of later diagnosis. The time from screening to diagnosis is critical to optimizing cancer care, yet the efficacy of navigation in reducing it is insufficiently documented. Here, the authors evaluate a culturally sensitive patient navigation program to reduce the time to diagnosis and increase the proportions of women diagnosed within 30 days and 60 days.

METHODS.

The authors analyzed 425 Latinas who had Breast Imaging Reporting and Data System (BI‐RADS) radiologic abnormalities categorized as BI‐RADS‐3, BI‐RADS‐4, or BI‐RADS‐5 from July 2008 to January 2011. There were 217 women in the navigated group and 208 women in the control group. Women were navigated by locally trained navigators or were not navigated (data for this group were abstracted from charts). The Kaplan‐Meier method, Cox proportional hazards regression, and logistic regression were used to determine differences between groups.

RESULTS.

The time to diagnosis was shorter in the navigated group (mean, 32.5 days vs 44.6 days in the control group; hazard ratio, 1.32; P = .007). Stratified analysis revealed that navigation significantly shortened the time to diagnosis among women who had BI‐RADS‐3 radiologic abnormalities (mean, 21.3 days vs 63.0 days; hazard ratio, 2.42; P < .001) but not among those who had BI‐RADS‐4 or BI‐RADS‐5 radiologic abnormalities (mean, 37.6 days vs 36.9 days; hazard ratio, 0.98; P = .989). Timely diagnosis occurred more frequently among navigated Latinas (within 30 days: 67.3% vs 57.7%; P = .045; within 60 days: 86.2% vs 78.4%; P = .023). This was driven by the BI‐RADS‐3 strata (within 30 days: 83.6% vs 50%; P < .001; within 60 days: 94.5% vs 67.2%; P < .001). A lack of missed appointments was associated with timely diagnosis.

CONCLUSIONS.

Patient‐centered navigation to assist Latina women with abnormal screening mammograms appeared to reduced the time to diagnosis and increase rates of timely diagnosis overall. However, in stratified analyses, only navigated Latinas with an initial BI‐RADS‐3 screen benefited, probably because of a reduction in missed diagnostic appointments. Cancer 2013. © 2012 American Cancer Society.  相似文献   
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