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BACKGROUND: We prospectively evaluated the usefulness of IgA tissue transglutaminase antibodies (IgA tTG) in the initial diagnosis of celiac disease (CD) and compared its diagnostic potential with that of IgA anti-endomysial antibodies (IgA EMA) and anti-IgA and IgG gliadin antibodies (AGA and AGG, respectively). METHODS: Sera of 23 untreated children fulfilling the revised ESPGHAN criteria for diagnosis of CD (Group I; mean age 10.8 y); 19 disease controls (Group II; mean age 8.5 y) presenting with chronic diarrhea, short stature or both; and 22 healthy children (Group III; mean age 8.8 y) were studied. These were tested in a blinded manner for AGA, AGG, IgA tTG (guinea pig as antigen) and IgA EMA. RESULTS: In Group I, IgA EMA was positive in 19, IgA tTG in 17, AGA in 14 and AGG in 17 patients. In Group II, these tests were positive in 1, 0, 2 and 14 patients, respectively and in Group III, in 0, 0, 0 and 1 child, respectively. Analyzing data from Group I and II, IgA EMA, IgA tTG, AGA and AGG had sensitivity rates of 83%, 74%, 61% and 74%, respectively; the specificity rates were 95%, 100%, 89% and 26%; positive predictive values were 95%, 100%, 88% and 55% and negative predictive values were 82%, 74%, 65% and 45%, respectively. CONCLUSION: IgA tTG is useful for the diagnosis of CD, with sensitivity and specificity rates comparable to those of EMA and this test is well suited for use in tropical countries like India.  相似文献   
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OBJECTIVE: To investigate whether orofacial tardive dyskinesia (OTD) is associated with frontal lobe dysfunction and whether either are related to the coping abilities independent of psychiatric symptoms in older people with psychotic disorders. METHODS: A total of 52 patients, aged over 65 years or over, who satisfied International Classification of Diseases, Tenth Revision criteria for psychotic disorders (F20-F29) were recruited into the study. OTD was measured using the Abnormal Involuntary Movements Scale and Waddington et al.'s (1993) criteria. Neuropsychological measures were specifically selected to assess different aspects of frontal function and coping was measured using a semistructured interview. Psychiatric symptoms were assessed using the Positive and Negative Syndrome Scale (PANSS). RESULTS: Patients with OTD showed more severe global cognitive impairment compared to patients without OTD. Group differences on measures of frontal lobe dysfunction were not maintained following adjustment for global cognitive impairment. Patients with OTD did not differ from patients without OTD on coping measures. Scores on the general psychopathology subscale of the PANSS, which includes symptoms associated with depression and anxiety, consistently predicted patients' negative perceptions of stressors and appraisals of coping, but cognitive impairment did not predict coping independent of symptoms. CONCLUSION: The association between coping and general psychopathology in older patients with psychosis warrants further investigation as both variables may be amenable to psychological interventions.  相似文献   
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Ehlers-Danlos syndrome – vascular type, the only lethal form, is rarely reported in dermatology literature. It is characterized by translucent, atrophic skin, easy bruising, arterial, intestinal and/or uterine fragility manifesting as varicose veins, aneurysms and vascular/visceral/uterine rupture. As its dermatopathologic features are not well elucidated, diagnosis is often made after a catastrophic complication or at autopsy. This 36 year-old non-consanguineous male had brown-black plaques with atrophy and frequent ulceration over legs and dorsal feet and tortuous varicose veins around ankles for the past 15 years. Perivenous skin was translucent and hypopigmented. He had multiple and ecchymotic keloids and small atrophic, pityriasis versicolor-like lesions over trunk. He did not have hypermobile/hyperextensible skin and joints and showed no systemic or investigative abnormality. Histopathologic features of atrophic lesion included blood extravasation in atrophic epidermis/dermis, focal clustering and dilatation of blood vessels, malformed vessel walls, abundant hemosiderin in the dermis and homogenously stained/whorled patterned collagen especially around blood vessels. Pathology of keloidal lesion showed new collagen and vascular fragility. These histopathologic features appear of diagnostic value especially in patients who have compatible clinical findings but cannot afford confirmation by biochemical testing for abnormal synthesis of type III procollagen or identification of mutations in the COL3A1 gene.  相似文献   
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A case of malignant fibrous histiocytoma of the mediastinum presenting with unusual features of fever and leucocytosis is reported. This is the youngest patient reported in the literature who had this tumour in the mediastinum.  相似文献   
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Retropharyngeal abscesses were fairly common in preantibiotic era but the advent of antibiotics has reduced the overall incidence of these abscesses. They still continue to occur specially in developing world and carry significant morbidity and even mortality if not managed properly. The prevalence of this abscess in the young children pose a bigger challenge, as the examination of oral cavity is difficult. Emphasis is placed on the age, sex, type, and duration of symptoms, bacteriology, methodology of diagnosis, therapy and complications. With proper antibiotic cover and surgical management, majority of patients today survive without major residual squeal. Hereby we present a series of 15 cases of retropharyngeal abscess.  相似文献   
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Synthesis and biological evaluation of prodrugs of zidovudine   总被引:4,自引:0,他引:4  
A series of prodrugs of zidovudine (AZT) has been synthesized in an effort to enhance the uptake of the prodrugs by the HIV-1 infected cells and to increase the plasma half-life of AZT. The 5'-OH function of AZT was esterified with various acids in the presence of DCC and 4-(dimethylamino)pyridine (DMAP). The prodrug moieties included (a) morpholine and N-phenylpiperazine-1-acetic acid, (b) 1,4-dihydro-1-methyl-3-nicotinic acid, (c) retinoic acid, and (d) certain amino acids. The anti-HIV-1 activity of the esters was determined in peripheral blood lymphocytes. The IC50 for AZT in this system was 0.12 microM whereas for prodrugs it ranged from 0.05 to 0.2 microM. The prodrugs were generally less cytotoxic than AZT except the retinoic acid ester. In vitro hydrolysis of the various esters in human plasma indicated that these agents were relatively stable toward plasma esterases with t1/2 ranging from 10 to 240 min. Drug uptake studies in H9 cells with radiolabeled analogues demonstrated that the retinoic acid ester achieved approximately 4-fold higher intracellular concentration than [3H]AZT. However, 1,4-dihydro-1-methyl-3-[(pyridylcarbonyl)oxy] ester (5) was the most active agent of this series and had a higher therapeutic index than AZT.  相似文献   
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