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71.
72.
73.
D G Pipelleers P A in 't Veld M A Pipeleers-Marichal W Gepts M van de Winkel 《Diabetes》1987,36(7):872-876
In the normal rat pancreas, only few islet cells express MHC-class II antigens. Their nature and function has not yet been elucidated. We report a method for the purification of Ia-positive islet cells by fluorescence-activated cell sorting. The isolated mononuclear cells appear of nonendocrine origin but contain vacuoles with partially digested secretory vesicles. Both insulin- and glucagon-immunoreactive granules were identified in these vacuoles of varying size and composition. It is suggested that at least part of the rat islet cells with class II antigen expression can exhibit phagocytotic properties leading to the uptake of fragments from damaged endocrine cells. This functional characteristic may implicate this particular islet cell type in the pathology of the endocrine pancreas in type I diabetes. 相似文献
74.
What Is Sufficient Evidence for the Reliability and Validity of Patient-Reported Outcome Measures? 总被引:1,自引:0,他引:1
75.
K B Ates S Boyacio?lu I Ta? A Gencer G Temu?in B Sahin 《Gastrointestinal radiology》1991,16(2):178-180
Bleeding into a pancreatic pseudocyst is a rare but life-threatening entity. Early diagnosis is crucial in its management. There are reports suggesting that computed tomography (CT), scintigraphy, endoscopic retrograde cholangiopancreatography (ERCP), and angiography could be the diagnostic maneuvers. In this report, we present a case of arterial bleeding into a pancreatic pseudocyst, which was diagnosed by the turbulent echo-currents seen in real-time ultrasonography. 相似文献
76.
77.
诸暨麻疹疫苗免疫持久性研究协作组 《中华流行病学杂志》1987,8(2):92-95
1985年2~6月间,研究基地五个乡发生显性麻疹122例,为基地建立以来前11年病例总数的9.4倍,87.7%的病例集中在小学和幼儿园。
显性感染仅见于麻疹HI抗体<1:2者。不同原因导致麻疹HI抗体<1:2者,在暴露于自然麻疹后,原发免疫失败全表现为显性感染,继发免疫失败主要表现为隐性感染或不感染。
本次麻疹流行,再次证实当人群麻疹HI抗体阳性率在85%左右、阳性GMT为10.8左右的免疫水平时,虽有传染源输入,除个别易感者特别集中的单位可酿成较高罹患率外。不致造成大的流行。此外还观察到研究观察对象在充分暴露于自然麻疹后可获高达75%的隐性感染率,认为这对巩固和提高人群免疫水平具有积极意义,因而实行一次有效的麻疹疫苗接种在目前是可行的。 相似文献
显性感染仅见于麻疹HI抗体<1:2者。不同原因导致麻疹HI抗体<1:2者,在暴露于自然麻疹后,原发免疫失败全表现为显性感染,继发免疫失败主要表现为隐性感染或不感染。
本次麻疹流行,再次证实当人群麻疹HI抗体阳性率在85%左右、阳性GMT为10.8左右的免疫水平时,虽有传染源输入,除个别易感者特别集中的单位可酿成较高罹患率外。不致造成大的流行。此外还观察到研究观察对象在充分暴露于自然麻疹后可获高达75%的隐性感染率,认为这对巩固和提高人群免疫水平具有积极意义,因而实行一次有效的麻疹疫苗接种在目前是可行的。 相似文献
78.
R. Nickel S. Lau B. Niggemann C. Sommerfeld U. Wahn the German Multicenter Allergy Study Group 《Clinical and experimental allergy》2002,32(9):1274-1277
BACKGROUND: Bronchial responsiveness (BR) to histamine or methacholin is a common finding in adult non-asthmatic patients with allergic rhinitis. OBJECTIVE: We tested whether BR is also present in children with a comparatively short history of allergic rhinitis in a paediatric cohort. METHODS: We performed pulmonary function tests and histamine challenges in a total of 654 children (age 7 years, participants of the German Multicenter Allergy Study) and compared PC20 FEV1 values in children with asthma, allergic rhinitis, asymptomatic allergic sensitization and non-atopic controls. RESULTS: Most pronounced BR to histamine was observed in allergic asthmatics (n = 28), irrespective of the presence or absence of allergic rhinitis. Furthermore, PC(20)FEV(1) values in non-asthmatic children with allergic rhinitis (n = 24) were not significantly different from those seen in asymptomatic atopic (n = 54) or non-atopic controls (n = 92). CONCLUSIONS: In contrast to adult study populations, 7-year-old non-asthmatic children with allergic rhinitis do not show a higher degree of BR than asymptomatic atopic or non-atopic controls. Therefore, secondary preventive measures in non-asthmatic children with allergic rhinitis (such as regular local anti-inflammatory therapy or specific immunotherapy) should be studied and applied more intensely to prevent bronchial hyper-responsiveness (BHR) and asthma in this high-risk group. 相似文献
79.
Coppo R; Cirina P; Amore A; Sinico R; Radice A; Rollino C; the Italian Group of Renal Immunopathology Collaborative Study on Henoch-Schonlein purpura in adults f; children i 《Nephrology, dialysis, transplantation》1997,12(11):2269-2276
Background: The presence and the pathogenetic role of
circulating IgA reacting with neutrophil cytoplasmic antigens (IgA-ANCA) in
patients with Henoch-Schonlein purpura (HSP) is still debated. This study
was aimed to investigate some characteristics of serum IgA and
macromolecular IgA in HSP patients, focusing on IgA-ANCA.
Methods: Eighty-seven HSP patients with biopsy proved
renal involvement (51 adults and 36 children) enrolled in a multicentre
study of the Italian Group of Immunopathology were investigated.
Results: Significantly high levels of IgA immune
complexes were found in both adults (P <0.05) and children (P
<0.01), while the binding of IgA to jacalin, was significantly low
in children with HSP (P <0.01) only. Two series of ELISA were done
for IgA-ANCA, in two different laboratories. Increased binding to PMN crude
extracts (P <0.01) without any modification in IgA binding to
proteinase 3 was found by either specific ELISA. Conversely, the binding of
IgA to myeloperoxidase (MPO) was found to be significantly (P <0.05)
increased with positive values in 25% of patients by one assay only. Three
of four sera with positive IgA-MPO ANCA exhibited binding in Western-blot
studies with the MPO preparation used in ELISA to a 28-kDa species.
D-galactose and N-acetyl-glucosamine decreased the binding of serum IgA to
MPO more in HSP than in controls (P <0.05).
Conclusions: The conflicting reports on IgA-ANCA may
reflect some atypical characteristics of the reaction which can be detected
only by some ELISAs. We suggest that not an antigen-antibody reaction but a
lectinic interaction due to abnormal composition of IgA carbohydrate side
chains may account for the IgA-ANCA reaction in patients with HSP
nephritis. 相似文献
80.
该文从疾病谱和死因谱的改变、医学模式的转变、卫生经费的降低、自我保健意识的改变四个角度,论述了全面开展 生活方式教育的必要性和重要性;从以社区为依托、以医院为基础、以生活方式为指导三个方面,探讨了生活方式教 育的工作模式. 相似文献