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排序方式: 共有457条查询结果,搜索用时 453 毫秒
21.
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
22.
Benjamin C. Trumble Eleanor Brindle Michalina Kupsik Kathleen A. O'Connor 《American journal of human biology》2010,22(6):775-781
Objectives: The male reproductive axis is responsive to energetic deficits, including multiday fasts, but little is known about brief periods of fasting (<24 hours). Reduced testosterone in low‐energy balance situations is hypothesized to reflect redirection of resources from reproduction to survival. This study tests the hypothesis that testosterone levels decrease during a minor caloric deficiency by assessing the effects of a single missed (evening) meal on morning testosterone in 23 healthy male participants, age 19–36. Methods: Participants provided daily saliva and urine samples for two baseline days and the morning following an evening fast (water only after 4 PM). Testosterone, cortisol, and luteinizing hormone were measured with enzyme immunoassays. Results: Fasting specimens had significantly lower overnight urinary luteinizing hormone (P = 0.045) and morning salivary testosterone than baseline (P = 0.037). In contrast to morning salivary testosterone, there was a significant increase in overnight urinary testosterone (P = 0.000) following the evening fast, suggesting an increase in urinary clearance rates. There was a marginal increase in overnight urinary cortisol (P = 0.100), but not morning salivary cortisol (P = 0.589). Conclusion: These results suggest the male reproductive axis may react more quickly to energetic imbalances than has been previously appreciated. Am. J. Hum. Biol., 2010. © 2010 Wiley‐Liss, Inc. 相似文献
23.
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
24.
保健食品微生物限度检查的方法学验证 总被引:3,自引:0,他引:3
目的:确认对保健食品进行微生物限度检查时,昕采用的细菌、霉菌及酵母菌计数和控制菌检查方法是否适合于该保健食品的微生物限度检查。方法:按2005年版中国药典微生物限度检查法及方法学验证实验要求,对21种保健食品进行了方法学验证。结果:10个品种(血尔口服液、金舒通胶囊、事轻松胶囊、梦玉胶囊等)分别对金黄色葡萄球菌和枯草芽孢杆菌有明显的抑菌作用,阳性对照菌回收率均低于70%。结论:保健食品采用 GB/T4789-2003食品卫生微生物学检查法进行检查时,其检验结果可能不够科学,建议参照2005年版中国药典要求,通过方法验证实验建立合理的检验方法。 相似文献
25.
BA DARLOW TE INDER KB SLUIS G NUTHALL N MOGRIDGE CC WINTERBOURN 《Journal of paediatrics and child health》1995,31(4):339-344
Objective: New Zealand soils are deficient in the essential micronutrient, selenium. New Zealand infants have low selenium levels at birth and experience a further decline if fed cows milk based formula. This study examined the selenium status of infants fed with a new commercially available selenium supplemented formula.
Methodology Forty-four newborn infants, whose mothers wished to formula feed, were randomized in an open controlled trial to be fed a commercially available selenium supplemented cows milk formula (containing 17 μg Se/L) or an unsupplemented formula (containing 4.6 μg Se/L). Cord, 1 and 3 month blood samples were obtained for selenium status (plasma and red cell selenium and glutathione peroxidase) and thyroid function.
Results Mean plasma selenium and glutathione peroxidase values were significantly higher in supplemented than unsupplemented infants at 1 month (unpaired t -tests; P <0.0001 and P = 0.001 respectively) and 3 months ( P <0.0001 and P = 0.0005). Analysis within treatment groups between time points (paired t -tests) showed that selenium supplementation prevented the fall in plasma selenium from birth to 1 month seen in unsupplemented infants and was associated with a rise in levels between 1 and 3 months ( P = 0.002).
Conclusions Supplementing cows milk formula with selenium to replicate the levels found in breast milk is nutritionally sound. Feeding from a few days of age with a formula containing 17 μg Se/L in infants with low selenium status at birth is sufficient to cause a rise to 80% of adult levels at 3 months of age. 相似文献
Methodology Forty-four newborn infants, whose mothers wished to formula feed, were randomized in an open controlled trial to be fed a commercially available selenium supplemented cows milk formula (containing 17 μg Se/L) or an unsupplemented formula (containing 4.6 μg Se/L). Cord, 1 and 3 month blood samples were obtained for selenium status (plasma and red cell selenium and glutathione peroxidase) and thyroid function.
Results Mean plasma selenium and glutathione peroxidase values were significantly higher in supplemented than unsupplemented infants at 1 month (unpaired t -tests; P <0.0001 and P = 0.001 respectively) and 3 months ( P <0.0001 and P = 0.0005). Analysis within treatment groups between time points (paired t -tests) showed that selenium supplementation prevented the fall in plasma selenium from birth to 1 month seen in unsupplemented infants and was associated with a rise in levels between 1 and 3 months ( P = 0.002).
Conclusions Supplementing cows milk formula with selenium to replicate the levels found in breast milk is nutritionally sound. Feeding from a few days of age with a formula containing 17 μg Se/L in infants with low selenium status at birth is sufficient to cause a rise to 80% of adult levels at 3 months of age. 相似文献
26.
Jirapongsananuruk O Donahue HL Trumble AE Leung DY 《The Journal of investigative dermatology》2000,114(1):200-203
Atopic dermatitis (AD) is associated with increased IL-4, IL-5, and IL-13 but decreased IFN-gamma production. This cytokine profile may account for the atopic features of this illness, including IgE upregulation. Recent studies have demonstrated that tumor necrosis factor (TNF)-beta is produced by Th1-like cells, but the cytokine modulation by TNF-beta and the clinical significance of this cytokine in AD is not known. Therefore, this study was carried out to determine the potential role of TNF-beta in AD. In this study, we cultured peripheral blood mononuclear cells from patients with AD and normal subjects with anti-CD3 monoclonal antibodies and investigated the production of TNF-beta by ELISA. The mean +/- SEM of TNF-beta production in AD was significantly lower than normal subjects (p = 0.03). The effect of TNF-beta on cytokine production was investigated by culturing peripheral blood mononuclear cells with anti-CD3 monoclonal antibodies in the presence or absence of TNF-beta. Compared with medium control, TNF-beta significantly decreased IL-5 (p = 0.0004) and IL-13 (p = 0.008) but increased IFN-gamma (p = 0.001) production. The effect of TNF-beta on IgE production was determined by culturing peripheral blood mononuclear cells in the IL-4- and anti-CD40-induced IgE production system. Interestingly, TNF-beta significantly decreased IgE (p = 0.02), but not IgG production compared with medium control. Our study demonstrates that TNF-beta production is downregulated in AD. This cytokine increases IFN-gamma production but decreases IL-5, IL-13, as well as IgE production. These findings suggest a potential role for TNF-beta in the pathogenesis of AD. 相似文献
27.
4-(Methylnitrosamino)-1-(3-pyridyl)-1-butanol (NNAL) is an important
metabolite of the tobacco-specific nitrosamine 4-(methylnitrosamino)-1-
(3-pyridyl)-1-butanone (NNK). Using the chiral derivatizing agent, (R)-
(+)-alpha-methylbenzyl isocyanate [(R)-(+)-MBIC], previous work has shown
that the enantiomeric ratio of metabolically formed NNAL and its
glucuronide derivative may be species dependent. However, the absolute
configuration of such NNAL has not been previously reported. Synthetically
prepared racemic NNAL was converted to diastereomeric esters by reaction
with (R)-(+)- and (S)-(-)-alpha-methoxy-alpha-
(trifluoromethyl)phenylacetic acid (MTPA) chloride (Mosher's reagent) and
the products were characterized by 1H-NMR. Based on chemical shift data,
the absolute configuration of NNAL in each diastereomeric ester was
assigned. Hydrolysis of (R)-NNAL-(R)-MTPA gave (R)-NNAL. This was converted
to the corresponding carbamate by reaction with (R)-(+)-alpha- MBIC and the
absolute configurations of the diastereomeric carbamates formed by reaction
of (R)- and (S)-NNAL with (R)-(+)-MBIC were thereby assigned. Conversion of
metabolically produced NNAL to the same carbamates allowed us to assign the
NNAL formed from NNK by rat liver microsomes as (R)-NNAL. The major and
minor NNAL-glucuronide diastereomers found in the urine of patas monkeys
and humans exposed to NNK were similarly assigned; they were formed from
(R)-NNAL and (S)- NNAL, respectively.
相似文献
28.
Fifty seven children with thoracic empyema (37 boys and 20 girls) aged less than 12 years were seen at the University of Port Harcourt Teaching Hospital between January 1989 and December 1991. Staphylococcus aureus was the most common organism isolated from the pus of these patients (36 (63%) patients). Pseudomonas aeruginosa, the next most common organism, was isolated in 10 (18%) patients. The most common symptoms at presentation were acute illness with fever and cough (51 (89%) patients). All the patients were treated with closed intercostal tube drainage and appropriate antibiotics. Decortication was resorted to in only one patient. There were two deaths and the overall survival rate was 97%. 相似文献
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