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81.
Chlamydial etiology of acute lower respiratory tract infections in children in the Sudan 总被引:2,自引:0,他引:2
B Herrmann MAM Salih BE Yousif O Abdelwahab P-A Mårdh 《Acta paediatrica (Oslo, Norway : 1992)》1994,83(2):169-172
The role of Chlamydia pneumoniae in 110 Sudanese children with signs of acute lower respiratory tract infections (ALRI) was investigated. Four (3.6%) had evidence of C. pneumoniae infection, of whom 3 were culture-positive, while 1 had an antibody response suggesting a recent infection. IgG antibodies at a titer of ≥1:32 to C. pneumoniae, Chlamydia psittaci and Chlamydia trachomatis were detected in 27 (24.5%), 27 (24.5%) and 7 (6.4%) of the 110 ALRI cases, respectively. C. pneumoniae, C. trachomatis or C. psittaci were not detected in nasopharyngeal secretions from any of 110 patients when fluorescence-labeled specific monoclonal antibodies were used. In a seroepidemiological survey, 318 healthy Sudanese persons aged between 1 month and 67 years were studied for C. pneumoniae antibodies. 相似文献
82.
Melanoses of the gastrointestinal tract 总被引:4,自引:0,他引:4
Electronmicroscopy and electron probe energy dispersive X-ray analysis studies have substantially contributed to our understanding of the various gastrointestinal tract melanoses. The nature of the pigment granules which occur in the various melanoses is discussed; their pattern of distribution in melanosis coli, melanosis ilei, melanosis duodeni and melanosis oesophagi is summarized and current knowledge of the aetiology and pathogenesis of these conditions is reviewed. Brief mention is also made of other examples of lipofuscin pigmentation, and a case of haemosiderosis ilei is described. 相似文献
83.
Nodular hyperplasia surrounding fibrolamellar carcinoma 总被引:2,自引:0,他引:2
We report a case of acetaminophen-induced liver necrosis in a 14-year-old girl. At autopsy, a 9 cm subcapsular nodule was present in the right lobe of the liver which showed distinct zonation: a central greyish white area of fibrolamellar carcinoma with a peripheral fleshy, tan-coloured rim ranging from 1 to 2 cm in thickness. This peripheral zone consisted of nodular, hyperplastic parenchyma resembling the changes seen in focal nodular hyperplasia, and stood out from the adjacent necrotic parenchyma. The sparing of this zone from the deleterious effects of acetaminophen provides indirect evidence of a predominantly arterial rather than portal blood supply to this region. The arterial supply was most probably derived from the tumour vasculature and may explain the parenchymal hyperplasia sometimes reported adjacent to a fibrolamellar carcinoma. Awareness of this phenomenon is essential when evaluating a needle biopsy, as sampling of this region may lead to a false negative diagnosis. 相似文献
84.
分析了7岁以下儿童视网膜脱离(RD)21例。儿童裂孔源性RD主要由外伤引起,非裂孔源性RD多与遗传、发育异常、Coat's病、眼内感染等因素有关。本文还讨论了儿童外伤性RD的临床特点和预防措施,强调了孕产期妇女保健对预防儿童非外伤性RD的意义。 相似文献
85.
Joen-Rong sheu Chao-Hsin Lin Jih-Luan chung Che-Ming Teng Tur-Fu Huang 《Thrombosis research》1992,66(6):679-691
Triflavin, an Arg-Gly-Asp (RGD)-containing peptide, purified from snake venom of Trimeresurus flavoviridis, inhibits human platelet aggregation through the blockade of fibrinogen binding to fibrinogen receptors associated with glycoprotein IIb/IIIa complex. In this report, we examined the effect of triflavin on tumor cells (human hepatoma J-5)-induced platelet aggregation (TCIPA) of heparinized platelet-rich plasma (PRP). ADP-scavenger agents, apyrase (10 U/ml) and creatine phosphate (5 mM)/creatine phosphokinase (5 U/ml) did not inhibit TCIPA while hirudin (5u/ml) completely inhibited it. J-5 cells initially induced platelet aggregation, then blood coagulation occurred. J-5 cells concentration-dependently shortened the recalcification time of normal as well as Factor VIII, IX-deficient human plasmas, while it was inactive at shortening the recalcification time of Factor VII-deficient plasma, suggesting J-5 cells induced platelet aggregation through activation of extrinsic pathway, leading to thrombin formation as evidenced by the amidolytic activity on S-2238 by expressing tissue factor-like activity. Triflavin inhibited TCIPA in a dose-dependent manner (IC50, 0.02 μM). When compared on molar ratio, triflavin was approximately 30,000 times more potent than GRGDS (IC50,0.58 mM). On the other hand, GRGES showed no significant effect on TCIPA, even its concentration was raised to 4 mM. Additionally, the monoclonal antibodies, raised against glycoprotein IIb/IIIa complex (i.e., 7E3 and 10 E5) inhibited J-5 TCIPA. In conclusion, we suggest the inhibitory effect of triflavin on J-5 TCIPA may be chiefly mediated by the binding of triflavin to the fibrinogen receptor associated with glycoprotein IIb/IIIa complex on platelet surface membrane. 相似文献
86.
We present an 8 year follow-up on a group of children with refractory epileptic seizures who participated in the early 1980s in a controlled group study on the effects of a broad-spectrum behavior modification treatment program on children with refractory epileptic seizures. In the original study, 18 children were divided into three groups: behavior modification group, attention control group, and control group. The purpose was to investigate the effects of a learning-based treatment program superimposed on a regular medical treatment program. Also, the effects of professional attention were evaluated. At the 10 week and 1 year follow-ups, only the group receiving the behavior modification intervention had a significantly reduced rate of seizure index. The present study investigates these same children 8 years later using the same methods of investigation for an additional 10 week period. The results indicate that a significant reduction in seizures was obtained only for the behavior modification group at the 8 year follow-up. 相似文献
87.
Leon A. Weisberg Jack Greenberg Antonio Stazio 《Computerized medical imaging and graphics》1988,12(6):379-383
The clinical and computerized tomographic (CT) findings in 10 patients with cerebral toxoplasmosis are reviewed. All patients with cerebral toxoplasmosis were homosexuals and/or intravenous drug users, and all patients had other manifestations of AIDS. Two presented with focal seizures, 4 presented with focal neurological deficit which progressively worsened, and 4 had evidence of diffuse neurological dysfunction (altered consciousness, generalized seizures). CT showed a single lesion in 3 patients and multiple lesions in 7 patients. Two patients had hypodense nonenhancing lesions(s). Eight patients had hypodense lesions with peripheral or nodular enhancement. The lesions were more commonly located in the cerebral hemispheres and subcortical gray matter nuclear masses (thalamus, basal ganglia). The finding of a hypodense lesion with a central slightly hyperdense noncalcified region that showed dense nodular homogeneous enhancement was quite characteristic of cerebral toxoplasmosis, but this pattern may also be seen in other neurological conditions including brain lymphomas. 相似文献
88.
89.
The phosphorylation patterns of isolated red blood cell (RBC) membranes labeled with [ γ-32p]ATP are altered by Zn++ ions. Zn++ ions caused an increased phosphate incorporation into a 72 KDa protein and several proteins in the 40–60 KDa region and a decrease in the labeling of a 53 KDa protein. The 72 KDa and 53 KDa proteins have been identified as protein 4.2 and a protease-cleaved fragment of protein 3, respectively. Evidence suggests that the changes in phosphorylation pattern may be due to the stimulation of endogenous membrane alkaline phosphatase(s). Our results suggest that Zn++, at physiological concentrations in the intact erythrocyte, could modulate the phosphorylation of selected proteins which may regulate their association in the cytoskeletal network. 相似文献
90.