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排序方式: 共有368条查询结果,搜索用时 15 毫秒
31.
Heterogeneity of large granular lymphocyte proliferations: delineation of two major subtypes 总被引:5,自引:0,他引:5
Two major types of lymphocytosis of large granular lymphocytes (LGLs) were observed. The proliferating LGLs in each type had distinct immunophenotypes, functional characteristics, and probably belonged to different cell lineages. The more common form (Type A) consisted of cells derived from the T cell lineage and had the T suppressor/cytotoxic phenotype (T11+, T3+, T8+). The expression of the Leu 7 and HLA-DR antigen was variable. These cells did not have natural killer (NK) function but showed a variable degree of antibody-dependent cell-mediated cytotoxic (ADCC) activity. Neutropenia was invariably present and rheumatoid arthritis and autoantibodies were frequent associations. These lymphocytes had many similarities to the major type of LGLs present in normal adult bone marrow. The other type of LGL lymphocytosis (Type B) consisted of cells lacking the antigens T3 and T8 but expressing M1 and NKH1. These cells possessed strong NK and ADCC activity but their cell lineage was not clear. Neutropenia and autoimmune phenomena were not detected. The cytochemical characteristics of the LGL granules from both types of patients were similar but differences in ultrastructure were observed. LGLs from Type B patients proliferated in the presence of Interleukin 2 (IL-2) and 12- O-tetradecanoyl-phorbol-13 acetate (TPA). Significant changes in their basic T11+, T3-, T8- phenotype were not observed. IL-2 and TPA, however, had profound influence on the NK function of the cells with enhancement in the case of IL-2 and marked suppression when stimulated by TPA. 相似文献
32.
33.
K F Schulze M Stefanski J Masterson R Spinnazola R Ramakrishnan R B Dell W C Heird 《The Journal of pediatrics》1987,110(5):753-759
The effect of energy and protein intakes on energy expenditure, energy balance, and amount and relative rate of both protein and fat deposition in new tissue was investigated in 19 low birth weight infants whose mean protein and energy intakes, respectively, were 2.24 g/kg/d and 113 kcal/kg/d (formula A, n = 8), 3.6 g/kg/d and 115 kcal/kg/d (formula B, n = 5), and 3.5 g/kg/d and 149 kcal/kg/d (formula C, n = 6). The higher energy intake (formula C) but not the higher protein intake (formula B) resulted in greater energy expenditure. Both the higher protein (formula B vs formula A) and higher energy intakes (formula C vs formula B) resulted in greater weight gain secondary, in group B, to a greater absolute rate of protein deposition and, in group C, to a greater absolute rate of fat deposition. The relative composition of the new tissue deposited reflected the proportional intakes of protein and energy. The numerical value of the protein/fat ratio (g/g) of the new tissue deposited by infants fed formulas A and C, the protein contents of which were low relative to energy contents, were similar and significantly lower than the numerical value of the protein/fat ratio of the new tissue deposited by infants fed formula B, which had a higher protein content relative to energy content. These findings suggest that the composition of weight gain is related to both the absolute amounts and the proportions of dietary protein and energy; thus, both must be considered in formulation of nutritional regimens for LBW infants. 相似文献
34.
Schizencephaly: diagnosis and progression in utero 总被引:2,自引:0,他引:2
Schizencephaly is an unusual condition of obscure etiology. Most theories of pathogenesis postulate an in utero insult leading to maldevelopment rather than destruction of brain. The cause has most often been described as vascular or idiopathic dysgenesis. The authors report a case in which two in utero ultrasound (US) examinations performed at 31 and 36 menstrual weeks demonstrated progressive deterioration of the relatively narrow, symmetrical clefts connecting the lateral ventricles with the subarachnoid space into broad defects that corresponded to the entire distribution of the middle cerebral arteries. The findings in this case document progressive destruction of brain tissue in utero and are consistent with a vascular cause rather than a failure of formation of portions of the cerebral mantle. 相似文献
35.
Benjamin J Cowling Lincoln LH Lau Peng Wu Helen WC Wong Vicky J Fang Steven Riley Hiroshi Nishiura 《BMC infectious diseases》2010,10(1):82
Background
After the WHO issued the global alert for 2009 pandemic influenza A (H1N1), many national health agencies began to screen travelers on entry in airports, ports and border crossings to try to delay local transmission. 相似文献36.
Oral Diseases (2010) 16 , 136–145 Objective: The oral cavity forms an indispensable part of the human microbiome, for its unique and diverse microflora distributed within various niches. While majority of these organisms exhibit commensalism, shifts in bacterial community dynamics cause pathological changes within oral cavity and distant sites. The aim of this review was to appraise the current and emerging methods of detecting bacteria of the oral cavity paying particular attention to the cultivation independent methods. Design: Literature pertaining to cultivation based and cultivation independent methods of oral bacterial identification was reviewed. Methods: The specific advantages and disadvantages of cultivation based, microscopic, immunological and metagenomic identification methods were appraised. Results: Because of their fastidious and exacting growth requirements, cultivation based studies grossly underestimate the extent of bacterial diversity in these polymicrobial infections. Culture independent methods deemed more sensitive in identifying difficult to culture and novel bacterial species. Conclusion: Apart from characterizing potentially novel bacterial species, the nucleic acid sequence data analyzed using various bioinformatics protocols have revealed that there are in excess of 700 bacterial species inhabiting the mouth. Moreover, the latest pyrosequencing based methods have further broadened the extent of bacterial diversity in oral niches. 相似文献
37.
Ed Wargent Matthew V Sennitt Claire Stocker Andrew E Mayes Louise Brown Jacqueline O'Dowd Steven Wang Alexandra WC Einerhand Inge Mohede Jonathan RS Arch Michael A Cawthorne 《Lipids in health and disease》2005,4(1):1-14
Background
Studies in rodents and some studies in humans have shown that conjugated linoleic acid (CLA), especially its trans -10, cis -12 isomer, reduces body fat content. However, some but not all studies in mice and humans (though none in rats) have found that CLA promotes insulin resistance. The molecular mechanisms responsible for these effects are unclear, and there are conflicting reports on the effects of CLA on peroxisomal proliferator-activated receptor-γ (PPARγ) activation and expression. We have conducted three experiments with CLA in obese mice over three weeks, and one over eleven weeks. We have also investigated the effects of CLA isomers in PPARγ and PPARα reporter gene assays.Results
Inclusion of CLA or CLA enriched with its trans -10, cis -12 isomer in the diet of female genetically obese (lep ob /lep ob ) mice for up to eleven weeks reduced body weight gain and white fat pad weight. After two weeks, in contrast to beneficial effects obtained with the PPARγ agonist rosiglitazone, CLA or CLA enriched with its trans -10, cis -12 isomer raised fasting blood glucose and plasma insulin concentrations, and exacerbated glucose tolerance. After 10 weeks, however, CLA had beneficial effects on glucose and insulin concentrations. At this time, CLA had no effect on the plasma TNFα concentration, but it markedly reduced the plasma adiponectin concentration. CLA and CLA enriched with either isomer raised the plasma triglyceride concentration during the first three weeks, but not subsequently. CLA enriched with its trans -10, cis -12 isomer, but not with its cis -9, trans -11 isomer, stimulated PPARγ-mediated reporter gene activity; both isomers stimulated PPARα-mediated reporter gene activity.Conclusions
CLA initially decreased but subsequently increased insulin sensitivity in lep ob /lep ob mice. Activation of both PPARγ and PPARα may contribute to the improvement in insulin sensitivity. In the short term, however, another mechanism, activated primarily by trans -10, cis -12-CLA, which probably leads to reduced adipocyte number and consequently reduced plasma adiponectin concentration, may decrease insulin sensitivity. 相似文献38.
PTEN抑癌基因在乳腺癌组织中的表达及其与乳腺癌微小转移灶的关系 总被引:1,自引:0,他引:1
目的:研究PTEN抑癌基因在乳腺癌组织中的表达,探讨其与乳腺癌病人的外周血、骨髓及前哨淋巴结微小转移灶之间的关系。方法:选择53例乳腺癌病人的组织标本,用免疫组织化学方法检测原发肿瘤PTEN蛋白的表达;用定量RT鄄PCR法测定原发肿瘤PTENmRNA的表达。以免疫细胞化学法检测外周血和骨髓中的微小转移灶;HE染色和免疫组织化学法检测前哨淋巴结中的微小转移灶。结果:外周血、骨髓及前哨淋巴结中微小转移灶的检出率分别是24.5%,56.6%,26.4%和41.5%。乳腺癌组织中PTEN蛋白表达呈丢失者占35.8%,后者与外周血和骨髓微小转移灶间无显著关系,而与前哨淋巴结中的微小转移密切相关(P≤0.001)。PTENmRNA的表达与外周血、骨髓及前哨淋巴结中的微小转移灶之间均无显著相关性。结论:乳腺癌组织中PTEN蛋白表达的丢失与前哨淋巴结中的微小转移有密切关系,可作为预测其早期转移的重要指标。 相似文献
39.
目的 探讨有关急危重病人血流动力学状态达到最佳化治疗研究中肺动脉导管 (Swan -Ganz)与复苏治疗的关系 ,评估生理、临床、治疗等方面因素对复苏治疗效果的影响。方法 从MEDLINE(英文医学文献资料网库 )中搜集所有与Swan -Ganz和血流动力学状态有关的 71篇研究文献。按照限定条件进行筛选 :①病人类型 :急性病 ,高危外科手术病人 ,创伤 ;②达到血流动力学指标正常值或超常值标准 ;③控制组死亡率 >2 0 % (危重组 )或 <15 % (一般组 ) ;④治疗后达到血流动力学指标的早晚 ;其中 2 1项研究接受Meta分析。结果 在危重组 ,早期达到血流动力学超常值治疗 ,2 1项研究中的 7项显示在控制组与治疗组之间死亡率有显著性的差别 (P <0 0 5 ) ;而晚期达到血流动力学超常值治疗的 6项研究 ,两组之间死亡率无显著性的差别 (P >0 0 5 )。在一般组 ,达到血流动力学正常值治疗的 5项研究和超常值治疗的 3项研究显示 ,控制组与治疗组之间死亡率无显著性的差别。结论 经Swan -Ganz引导早期达到血流动力学超常值治疗 ,能降低重病组的死亡率。 相似文献
40.
Victoria Y Kan Vladimir Marquez Azalgara Jo-Ann E Ford WC Peter Kwan Siegfried R Erb Eric M Yoshida 《Journal canadien de gastroenterologie》2015,29(2):72-76