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Ethnic comparisons are extremely important and useful for studying the HLA component involved in insulin-dependent diabetes mellitus (IDDM) predisposition. To date there have been only a few reports on the association of HLA loci and IDDM in Chinese. We report here a study on DQA1*Arg52, DQB1*nonAsp57, and DRB1*04 in IDDM children and control adults among Han Chinese living in Taiwan. One hundred and fourteen unrelated children (62 boys) with IDDM were studied. Their ages at diagnosis were between 0.3 and 15.0 years (6.8 +/- 3.6 years). The control population consisted of 120 randomly selected normal adults. DQA1*Arg52(+/+), DQB1*nonAsp57(+/+), and DRB1*04(+/-) were associated with IDDM (RR = 11.50, 2.21, and 2.82; p = 1.11 x 10(-15), 2.84 x 10(-3), and 1.98 x 10(-4), respectively). DQA1*Arg52, DQB1*nonAsp57, and DRB1*04 conferred risks for IDDM (RR = 12.79, 7.11, and 2.83; pc = 8.22 x 10(-4), 5.35 x 10(-3), and 5.68 x 10(-4), respectively). Combinations of DQA1*Arg52 and DRB1*04 conferred the highest risk for IDDM (RR = 19.64, pc = 5.4 x 10(-5)). DQA1*Arg52 was associated with IDDM in subjects with DQB1*nonAsp57+ (RR = 14.87, pc = 2.41 x 10(-4)) and DQB1*nonAsp57 was also associated with IDDM in subjects with DQA1*Arg52+ (RR = 8.41, pc = 1.54 x 10(-3)), suggesting that DQA1*Arg52 and DQB1*nonAsp57 are interacting. This study demonstrates that DQA1*Arg52, DQB1*nonAsp57, and DRB1*04 confer susceptibility for IDDM to Chinese children. A combination of DQA1*Arg52 and DRB1*04 confers the highest risk and it is suggested that a susceptibility gene might be situated between DQA1*Arg52 and DRB1*04 or both are synergistic. There is an interaction between DQA1*Arg52 and DQB1*nonAsp57 and homozygosity for DQA1*Arg52/DQB1*nonAsp57, which encodes four susceptibility DQ heterodimers, confers a high risk. 相似文献
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BACKGROUND & AIMS: Whether inflammation of the cardia indicates gastroesophageal reflux disease (GERD) and/or is a manifestation of pangastritis caused by Helicobacter pylori infection is unknown. The aim of this study was to evaluate the relationship between cardia inflammation, H. pylori infection, and cardia intestinal metaplasia in patients with and without GERD. METHODS: Patients with GERD were compared with controls undergoing endoscopy for a variety of other conditions. Endoscopic biopsy specimens from the distal esophagus and cardia, fundus, and antrum were evaluated for inflammation, H. pylori infection, and intestinal metaplasia. RESULTS: Neither the prevalence of H. pylori infection (controls, 48%; GERD, 41%) nor cardia inflammation (controls, 41%; GERD, 40%) differed between groups. All 11 controls and 22 of 23 patients with GERD (96%) and cardia inflammation had H. pylori infection. Esophagitis was more common among GERD patients (33%) than controls (7%; P = 0.01). Cardia intestinal metaplasia was more common among controls (22%) than GERD patients (3%; P = 0.01); all had cardia inflammation, 7 had H. pylori infection, and 6 had metaplasia elsewhere in the stomach. CONCLUSIONS: The prevalence of cardia inflammation is similar in patients with and without GERD and is associated with H. pylori infection (P < 0.001). Cardia intestinal metaplasia is associated with H. pylori-related cardia inflammation (P = 0.01) and intestinal metaplasia elsewhere in the stomach, indicating that it is distinct from Barrett's esophagus. 相似文献
34.
MV Zhernovo? SV Lebedev AA Grigoriuk IuA Krasnikov PV Kharitonski? 《Canadian Metallurgical Quarterly》1998,40(7):676-681
The influence of a constant magnetic field (strain 40 kA/m) on retina pigmentary cells of grass frog (Rana temporaria) and grey pigeon (Columba livia) eyes was investigated. Changes in the number and length of melanocytes appendixes were noticed accompanied by formation of thickenings in which melanosomes sized from 0.1 to 0.5 micron are moving. It is established that magnetic properties of eye retina pigmentary cells depend on the presence of Fe3+ in melanin. A theoretical model of paramagnetic receptor has been elaborated, according to which the induction of a magnetic field, formed by melanocyte, makes of the order 100 pT1. This value well compares with the size of magnetic field of a nervous impulse (120 pT1), extending throughout a nervous fibre of the frog sciatic nerve (Wikswo et al., 1980). This allows to suggest a possible unsynaptic way of transferring the information about the perceived magnetic field. 相似文献
35.
MV Pitzalis F Mastropasqua A Passantino F Massari L Ligurgo C Forleo C Balducci F Lombardi P Rizzon 《Canadian Metallurgical Quarterly》1998,97(14):1362-1367
BACKGROUND: Depressed baroreflex sensitivity obtained by means of a phenylephrine test plays a prognostic role in patients with a previous myocardial infarction. Our purpose was to evaluate the correlation and agreement between the baroreflex sensitivity obtained with phenylephrine and that obtained by two noninvasive methods: the alpha-index and sequence analysis. METHODS AND RESULTS: The alpha-index was measured by means of the spectral analysis of RR and systolic blood pressure variabilities in both the high- and low-frequency bands; sequences were identified from simultaneously recorded time series in which the RR and systolic blood pressure concurrently increased or decreased. Noninvasive baroreflex sensitivity tests were performed during both spontaneous and controlled respiration. Fifty-two consecutive patients with recent myocardial infarction underwent the analyses. Although the correlations between phenylephrine and either of the noninvasive methods were always significant, those found during controlled respiration had the highest r values (r=.70). However, the limits of agreement calculated by means of the Bland and Altman method were wide for both noninvasive methods. CONCLUSIONS: The results obtained by means of noninvasive baroreflex sensitivity assessments should not be used in clinical practice as an alternative to those obtained by the phenylephrine method. 相似文献
36.
BACKGROUND: Although a compulsory examination in medical English has been present in the medical degree curriculum in Italy since 1990, guidelines indicating what should be learnt and suggesting some means of overcoming the various problems this entails are still lacking. OBJECTIVE: To investigate the main features of teaching English in the Medical Faculties and enquire into how the various problems are solved in the individual English teaching units. METHOD: A questionnaire addressing the above issues was sent out to all the Italian Universities with a Medical Faculty. RESULTS: The first finding of our survey was that response was very poor: less than 30% of the survey volunteered any reply. Within the very reduced sample which responded, there was a high degree of variation among the solutions adopted, although the underlying problems were perceived to be much the same throughout Italy. CONCLUSIONS: The general objective of the English course for medicine should be more precisely defined, together with a series of specific minimum skills the student should possess to pass the final examination. A closer collaboration among the English teaching units might help to standardize these requirements, improve the quality of the teaching and hence the level of proficiency in English for the specific purpose of medical practice. 相似文献
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MV Kamath J Halton A Harvey S Turner-Gomes A McArthur RD Barr 《Canadian Metallurgical Quarterly》1998,12(3):635-640
Lower levels of baseline ventilatory function have consistently been associated with increased risk of cardiovascular mortality in prospective studies, but the underlying mechanisms are not known. Increased risk of coronary heart disease is associated with higher serum insulin levels. This report examines the relationship between ventilatory function and indirect measures of insulin resistance. Cross-sectional data from 922 nondiabetic participants in the Normative Aging Study were analysed using multiple linear regression models with adjustment for potential confounders. Forced vital capacity (FVC) and forced expiratory volume in one second (FEV1) were examined in relation to indicators of insulin resistance, i.e. fasting insulin and the fasting insulin resistance index (FIRI). Diabetics were excluded because impaired insulin secretion interferes with the validity of these as measures of insulin resistance. Fasting insulin and FIRI were negatively correlated with FVC and FEV1 (all p< 0.001). These associations persisted after adjusting for potential confounders including age, height, body mass index, waist to hip circumference ratio, physical activity, alcohol intake and smoking in separate multiple linear regression models, for both insulin (all p< or =0.0008) and FIRI (all p< or =0.0001). Negative cross-sectional associations between ventilatory function and indirect measures of insulin resistance were found in nondiabetic males. Insulin resistance may contribute to the previously unexplained association between ventilatory function impairment and cardiovascular mortality. Mechanisms underlying the relationship between insulin resistance and decreased ventilatory function remain to be elucidated. 相似文献
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40.
Simultaneous bleaching of vital teeth and an open-chamber nonvital tooth with 10% carbamide peroxide
OBJECTIVE: The purpose of this study was to evaluate the effectiveness of bleaching a nonvital tooth with an open pulp chamber while simultaneously bleaching the other vital teeth with 10% carbamide peroxide. METHOD AND MATERIALS: Ten discolored nonvital teeth were treated. Each nonvital tooth was prepared as in the conventional "walking bleaching" fashion, so that the gutta-percha was sealed from the pulp chamber. The 10% carbamide peroxide was injected into the chamber of the nonvital tooth and loaded into the custom-fitted tray for all teeth. The nonvital teeth were bleached from both the inside and the outside. The patient closed the orifice with a cotton pellet during the day and changed the cotton pellet after meals. The patient applied fresh solution nightly. RESULTS: All teeth were successfully lightened. The time required to lighten the nonvital tooth was related to the duration of the discoloration. CONCLUSION: With proper patient selection and education, this technique can provide an effective way to lighten nonvital and vital teeth simultaneously, especially where extended treatment time may be required for difficult discolorations. 相似文献