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71.
Daniel R. Budman E. Bruce Merchant Alfred D. Steinberg Bernard Doft M. Eric Gershwin Elaine Lizzio J. Patton Reeves 《Arthritis \u0026amp; Rheumatology》1977,20(3):829-833
Thirty-seven patients with criteria for systemic lupus erythematosus (SLE) and 18 normal controls were studied for their spontaneous background IgM antibody plaque-forming cell number to specific chemical haptens. Active SLE patients had significantly more plaque-forming cells in their peripheral blood to a total of five chemical determinants than did patients with inactive disease or controls. This increased number of plaque forming-cells correlated with depressed serum C3 levels by Spearman rank-order analysis. The finding of elevated numbers of spontaneous IgM plaque-forming cells to defined chemical haptens supports the concept that active SLE demonstrates a generalized increase in B-cell activity toward a variety of antigens. 相似文献
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Beatriz Gómez-González Horacio Merchant LariosAlfonso Escobar 《International journal of developmental neuroscience》2011,29(8):839-846
Brain endothelial ultrastructural properties contribute to maintain proper blood-brain barrier (BBB) function. Several physiological and pathological conditions have been shown to alter BBB permeability to blood-borne molecules, acute and chronic stress among them. In the rat, early life stress increased transvascular transport of Evans blue, however, the route of tracer extravasation is not fully known; therefore the aim of the present experiment was to describe the ultrastructural changes in endothelial cells subsequent to chronic perinatal stress in order to ascertain the route for transvascular transport of an electrodense tracer. Pregnant Wistar rats and their litters were used. Four pregnant rats were subjected to forced swimming between gestational days 10 to 20. After delivery, half of the control litters underwent 180 min maternal separation from postnatal day 2 to 20. Controls were kept free of any stress manipulation. At sacrifice between postnatal days 1 to 30 subjects were given intracardially the lectin wheat germ agglutinin conjugated to horseradish peroxidase (WGA-HRP). WGA-HRP stained hippocampi were processed for ultrastructural analysis, transmission electron micrographs were obtained and endothelial ultrastructural parameters quantified using the ImageJ software. Both stress procedures accelerated gross microvessel development by decreasing capillary wall thickness and endothelial microvilli. However, early-life stress also neutralized endothelial glycocalyx, increased vesicle-mediated transport and tended to promote the formation of secondary lysosomes containing endocytosed WGA-HRP vesicles, all parameters of altered endothelial cell function. Tight junction development in both stress groups was similar to the control pups. 相似文献
75.
MSTM Almeida SCB Lima LL Carvalho JVM Almeida LG Santos JRA Rolim TE Rocha 《Journal of cutaneous pathology》2010,37(11):1170-1173
Systemic sclerosis (SSc) is an autoimmune systemic disease characterized by small vessel involvement that leads to tissue ischemia and fibroblast stimulation resulting in accumulation of collagen (fibrosis) in the skin and internal organs. Lipomembranous panniculitis is a peculiar type of fat necrosis and has been reported with clinical conditions, commonly with peripheral vascular diseases. We describe a case of a 43‐year‐old woman with SSc manifestations, who presented with black scaly skin plaques, associated with thickening of the subcutaneous fat tissue, on the lateral surface of her thighs, her calves, gluteal area and lower abdomen. Biopsy revealed lipomembranous panniculitis. Lipomembranous changes have been seen in connective tissue disorders such as lupus profundus, morphea, systemic sclerosis and panniculitis associated with dermatomyositis, but rarely in thighs, calves, gluteal area and lower abdomen. Almeida MSTM, Lima SCB, Carvalho LL, Almeida JVM, Santos LG, Rolim JRA, Rocha TE. Panniculitis–An unusual cutaneous manifestation of systemic sclerosis. 相似文献
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Rashid Merchant Abhay Jain Amish Udani Vipla Puri Mallika Kotian 《Indian pediatrics》2010,47(2):165-167
This study was conducted to determine L-carnitine levels in regularly transfused and chelated beta thalassemia patients (n=40; mean age, 17.5±5.0 years).Ten age matched controls were also studied. The mean L-carnitine level in thalassemic patients
was 23.71±7.3 μM as compared to control 29.26±2.37μM (P<0.0001). Mean Carnitine was significantly lower (P=0.037) in those with ferritin greater than 2000ng/dL (22.80±6.97μM) in comparison to those with ferritin less than 2000ng/dL
(30.1±7.77μM). Although Carnitine levels in non vegetarians was higher (26.91 ±8.4μM) than in vegetarians (22.34±6.55μM),
this difference was not statistically significant (P=0.072). We conclude that L-carnitine levels were found to be lower in thalassemics as compared to age matched controls. 相似文献
79.
Video as an Effective Method to Deliver Pretest Information for Rapid Human Immunodeficiency Testing
Roland C. Merchant MD MPH ScD Melissa A. Clark PhD Kenneth H. Mayer MD George R. Seage III MPH ScD Victor G. DeGruttola ScD Bruce M. Becker MD MPH 《Academic emergency medicine》2009,16(2):124-135
Objectives: Video‐based delivery of human immunodeficiency virus (HIV) pretest information might assist in streamlining HIV screening and testing efforts in the emergency department (ED). The objectives of this study were to determine if the video “Do you know about rapid HIV testing?” is an acceptable alternative to an in‐person information session on rapid HIV pretest information, in regard to comprehension of rapid HIV pretest fundamentals, and to identify patients who might have difficulties in comprehending pretest information. Methods: This was a noninferiority trial of 574 participants in an ED opt‐in rapid HIV screening program who were randomly assigned to receive identical pretest information from either an animated and live‐action 9.5‐minute video or an in‐person information session. Pretest information comprehension was assessed using a questionnaire. The video would be accepted as not inferior to the in‐person information session if the 95% confidence interval (CI) of the difference (Δ) in mean scores on the questionnaire between the two information groups was less than a 10% decrease in the in‐person information session arm’s mean score. Linear regression models were constructed to identify patients with lower mean scores based upon study arm assignment, demographic characteristics, and history of prior HIV testing. Results: The questionnaire mean scores were 20.1 (95% CI = 19.7 to 20.5) for the video arm and 20.8 (95% CI = 20.4 to 21.2) for the in‐person information session arm. The difference in mean scores compared to the mean score for the in‐person information session met the noninferiority criterion for this investigation (Δ = 0.68; 95% CI = 0.18 to 1.26). In a multivariable linear regression model, Blacks/African Americans, Hispanics, and those with Medicare and Medicaid insurance exhibited slightly lower mean scores, regardless of the pretest information delivery format. There was a strong relationship between fewer years of formal education and lower mean scores on the questionnaire. Age, gender, type of insurance, partner/marital status, and history of prior HIV testing were not predictive of scores on the questionnaire. Conclusions: In terms of patient comprehension of rapid HIV pretest information fundamentals, the video was an acceptable substitute to pretest information delivered by an HIV test counselor. Both the video and the in‐person information session were less effective in providing pretest information for patients with fewer years of formal education. 相似文献
80.
加替沙星无菌检查方法的建立与标准操作探讨 总被引:4,自引:0,他引:4
目的:建立加替沙星原料及制剂无菌检查法及标准操作方法。方法:按2005年版中国药典无菌检查法验证实验的有关要求,通过接种阳性代表菌株,对薄膜过滤、添加中和剂等去除加替沙星抗菌活性的实验方法和条件进行验证,逐步建立加替沙星原料及制剂无菌检查的标准操作方法。结果:在对加替沙星不同原料及制剂样品适当的处理基础上,采用薄膜过滤法,以0.1%蛋白胨水溶液作为冲洗液,约每滤筒300 mL 的冲洗量,每筒培养基中加入0.1 mol·L~(-1)硫酸锰溶液3 mL 可去除加替沙星对细菌的抑菌作用。结论:加替沙星具有较强的抑菌活性,通过适当的样品处理、薄膜过滤法和添加硫酸锰溶液作为重金属络合剂,去除加替沙星抑菌活性,可对解决喹诺酮类抗生素无菌检查问题起到较好的参考作用。 相似文献