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71.
Leukocyte adhesion molecule expression and T cell naïve/memory status following isoproterenol infusion 总被引:1,自引:0,他引:1
This study examined adhesion molecules on peripheral leukocytes following a 30-min infusion of the beta-adrenergic agonist isoproterenol in 23 healthy subjects. In response to isoproterenol, the number of CD8 +CD62L- T cells and both CD62L+ and CD62L-natural killer (NK) (CD3 CD16+ 56+) cells increased markedly in circulation (p < 0.001). In addition, the surface density of CD62L was significantly lower on both CD8+ and CD4+ T cells (p < 0.001). Plasma levels of soluble CD62L remained unchanged, arguing against an isoproterenol-induced shedding of L-selectin. In contrast to CD62L, the surface density of the beta2 integrin LFA-1 (CD11a) was higher on circulating lymphocytes (p < 0.001) (but not monocytes or lymphocytes) post-infusion. Isoproterenol also led to a mobilization of memory/activated CD8+CD29high T cells (p < 0.01), but had no significant effect on the number of circulating CD8+ CD45RA+ CD62L+ na?ve T cells. beta blockade with the non-specific antagonist propranolol eliminated these isoproterenol-induced effects. 相似文献
72.
Charles AS Karamagi James K Tumwine Thorkild Tylleskar Kristian Heggenhougen 《BMC international health and human rights》2006,6(1):6-10
Background
Uganda began to implement the prevention of mother-to-child transmission (PMTCT) of HIV programme in 2000, and by the end of 2003 it had expanded to cover 38 of the 56 districts including Mbale District. However, reports from Mbale Hospital showed that less than 10% of pregnant women accepted antenatal HIV testing. We therefore conducted a study to determine the proportion of pregnant women who tested for HIV and the gaps and barriers in PMTCT implementation. 相似文献73.
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76.
AS Grumach RC Carmona D Lazarotti MA Ribeiro RB Rozentraub ML Racz A Weinberg MMS Carneiro-Sampaio 《Acta paediatrica (Oslo, Norway : 1992)》1993,82(3):284-290
Breast milk samples from three groups of Brazilian women were evaluated: G1, mothers delivering term babies of low birth weight (n=16); G2, mothers delivering preterm babies of appropriate birth weight (n = 20); G3, mothers delivering term babies of appropriate birth weight ( n = 30). Milk samples were obtained at 48 h and on the 7th, 15th, 30th and 60th days after delivery and they were analyzed for lysozyme and total IgA levels and for the presence of specific antibodies against Poliovirus types I, II, III, Rotavirus, Herpes simplex virus, Varicella zoster and Cytomegalovirus. The groups were not statistically different in relation to mother's age, parity, type of delivery or socio-economic levels. IgA levels were higher in both low-birth-weight groups (G1 & G2) compared to the control group (G3) throughout the study period. Lysozyme levels decreased up to the 15th day, increasing thereafter up to the 60th day in all groups. Specific antibodies were detected throughout the study period, with no differences among groups. We conclude that breast milk composition of mothers delivering low-birth-weight babies (G1 & G2) was similar despite the different gestational ages. 相似文献
77.
The incidence of transient hypogammaglobulinaemia of infancy (THI) detected in a major paediatric centre over a 10 year period was examined. A total of 2468 subjects less than 2 years of age had an IgG measurement taken between July 1979 and March 1990. Subjects with known immunodeficiencies were excluded. Fifteen patients were classified as having THI with an initial IgG level less than the fifth centile followed by a second measurement within the normal range. A further 24 patients were identified as having possible THI with a single low IgG concentration. There were 60,174 live births each year in Victoria in the years 1979-88. This gives an incidence of proved THI of 23 per 10(6) births, and including proved and probable THI an incidence of 61 per 10(6) live births. Of those patients with proved THI 12/15 had symptoms of either atopic disease or food allergy/intolerance and three had gastrointestinal symptoms without any evidence of atopic disease. At presentation 12/15 (80%) were IgA deficient and 9/15 had IgM concentrations less than the 20th centile for age. It is suggested that in view of the preponderance of atopic and food intolerant patients that subclinical protein loss from the bowel due to allergic inflammation may be a contributing factor to the development of THI in some patients. 相似文献
78.
Abnormal dinitrochlorobenzene skin sensitization: a prognostic sign of survival in head and neck squamous cell carcinoma 总被引:1,自引:0,他引:1
Dinitrochlorobenzene (2-4 DNCB) forms a hapten with skin protein when topically applied. The delayed hypersensitivity reaction which secondary application produces is useful to measure cell-mediated immunity as a gross measure of cancer immunity. Lymphocytopenia and anergy to attempted delayed hypersensitivity elicitation may both reflect poor host response to neoplasia. A prospective study on 55 patients with localized or regional squamous cell carcinoma of the larynx, pharynx and mouth was done. These patients were sensitized and stimulated with DNCB and lymphocyte counts measured. Eighty-eight percent of positive DNCB reactors were alive and tumor free at one year while 53 percent of non-responders survived free of disease. All 19 DNCB responders with normal or increased lymphocyte counts survived without recurrence. The potential usefulness of prognostic evaluation of host response is described. 相似文献
79.
Mucoceles of the sphenoid or posterior ethmoid sinuses usually behave in a similar manner. Because of the thinness of surrounding bone and the proximity of vital structures, these lesions can expand aggressively at a clinically alarming rate. Presenting symptoms vary but characteristically include headache and ocular disturbance. Careful radiologic evaluation helps in the correct assessment of these lesions. The authors feel that the rhinologic approach to the sphenoid cavity, via an external ethmoidotomy, affords the best visualization possible of the diseased area without entailing possibly serious central nervous system complications. Six cases are discussed from the standpoint of presenting signs and symptoms, radiologic assessment, therapy and outcome. 相似文献