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81.
Objective To detect new mutations among 29 glucose-6-phosphate dehydrogenase (G6PD) deficient individuals from Yunnan province. Methods The nitroblue tetrazolium (NBT) method was used to screen G6PD deficient individuals. Mutation was identified by single strand conformation polymorphism (SSCP), amplification created restriction site (ACRS), amplification refractory mutation system (ARMS) and DNA sequencing. Results Among 29 cases, 18 cases of G1388A, 1 case of C1004A, and 1 case of G1381A were identified. Nine cases remained to be defined. The G1381A mutation is a novel mis-sense mutation, with a substitution of threonine for alanine (A461T). The resultant G6PD had reduced enzymatic activity. In addition, G1381A caused a restriction site of Stu I to disappear, providing a rapid method for the detection of this mutation. Conclusion A novel mis-sense mutation G1381A was found. This mutation results in a substitution of threonine for alanine, producing enzyme with reduced activity. The loss of the Stu I restriction site offers a rapid method for the detection of this mutation. 相似文献
82.
A case is presented of an eight-year-old child with a mediastinal tumour, who had developed acute renal failure following the institution of steroid therapy. Intrapleural analgesia was successfully used for the insertion of a peritoneal dialysis catheter so that the considerable risks of general anaesthesia were avoided. Subsequent dialysis allowed chemotherapy to commence and, as a result of the shrinkage in tumour size, general anaesthesia was administered safely two days later. The purpose of this report is to highlight the use of intrapleural analgesia in children as an alternative to general anaesthesia, when the latter is contraindicated. The mechanism of action of intra-pleural analgesia and the risks of anaesthesia in the presence of a mediastinal tumour are discussed. 相似文献
83.
Costa LA Pereira AM 《Cadernos de saúde pública / Ministério da Saúde, Funda??o Oswaldo Cruz, Escola Nacional de Saúde Pública》1995,11(3):448-455
This paper examines the peculiarities of the expression of emotion in a poor neighborhood from Northeastern Brazil, the bairro of Nordeste de Amaralina, in Salvador, Bahia. Focusing on the expression of sadness, we built a scheme in which to understand how the informants perceive, identify, and deal with this emotion in the course of their daily lives. We attempted to reach an understanding of the wavs people in the bairro interpret sadness. In order to accomplish this goal. we built a semantic network which revealed three main clusters of emotional expression: the inner set, the bodily set, and the interactional set. We came to realize the various superpositions benween the universe of emotional expression and the local concept of person. 相似文献
84.
INTRODUCTION: The register of death by cause, sex and age groups of residents in 1994 in Rio Grande do Sul (RS) and Santa Catarina (SC), two Brazilian southern states, were studied to calculate the years of life lost (YLL), one of the two components that summarize disability adjusted life years (DALY), in RS, SC and Brazil. METHODS: The methodology employed is the same used in the Global Burden of Disease study to quantify the mortality component (YLL) of DALY in the world. RESULTS: The results show that the greatest proportion and rates caused by Group II (Noncommunicable diseases), linked with more advanced stages of the epidemiological transition, in RS, SC and Brazil. But in both states and especially in Brazil, Group I (Communicable, maternal, perinatal and nutritional conditions) causes an important proportion of YLL. The Group III (Injuries) was the second more important group in RS and SC and the third in Brazil. Road traffic accidents are particularly important in SC, where the intentional injury rate is half than the one in RS. The leading causes of YLL were road traffic accidents, ischemic heart disease and cerebrovascular disease in SC, and ischemic heart disease, cerebrovascular disease and road traffic accidents in RS. CONCLUSIONS: Death certification in the southern region of Brazil has a complete coverage and miscoded death proportion is small, providing a reliable mortality information. DALY allow comparing fatal and nonfatal health outcomes to determine the importance of different diseases and to establish health priorities. DALY are also an useful tool to identify disadvantaged groups, target health interventions and provide information for social control of resource allocation. 相似文献
85.
This paper aims to discuss which one is the best estimator of past diet: a retrospective report or a recent diet recall. The analysis included 13 articles published between 1984-1997 and selected from a MEDLINE search and from other reviews on this subject. The selection criterion was the use of a food frequency questionnaire (FFQ) in a validation study of retrospective report of dietary intake in remote past. Literature review shows that even taking into account misclassification, retrospective report of diet usually yields to a more reliable estimate of past diet pattern than current report. Past diet recall was strongly influenced by current intake and by diet patterns change. Analyzed investigations indicate that agreement between original and retrospective report was higher either for foods eaten rarely or frequently and lower for foods moderately consumed. This review allows considering the FFQ as a valuable instrument when studying the role of diet on the etiology of chronic diseases. 相似文献
86.
Pereira MA Folsom AR McGovern PG Carpenter M Arnett DK Liao D Szklo M Hutchinson RG 《Preventive medicine》1999,28(3):304-312
BACKGROUND: The epidemiologic observation that physical activity reduces the risk for hypertension has only been made for white men who self-reported hypertension. This study examined physical activity and clinically determined incident hypertension in black and white men and women of the Atherosclerosis Risk in Communities (ARIC) Study. METHODS: ARIC is a population-based prospective study with four U.S. clinic centers. The present analyses included 7,459 black and white adults 45-65 years of age. Hypertension (systolic/diastolic blood pressure >/= 140/90 mm Hg) was defined by blood pressure measured by a random-zero device or medication use. Physical activity was assessed with the Baecke questionnaire. RESULTS: After adjustment for age, baseline blood pressure, ARIC center, education, body mass index, waist-hip ratio, parental history of hypertension, cigarette smoking, alcohol consumption, and diet, white men in the highest quartile of leisure activity (primarily cycling and walking) had a 34% lower odds of developing hypertension over 6 years compared to the least active (OR = 0.66, 95% CI = 0.47-0.94; P for quartile trend = 0.01). Baseline activity was not associated with incident hypertension in white women or blacks. CONCLUSIONS: Leisure-time physical activity reduces the odds of hypertension in middle-aged white men. Additional studies in women and blacks are needed. 相似文献
87.
de Almeida CE Pereira AJ Marechal MH Pereira G Cruz JC Ferraz JC Giordani AJ Khalil CM Martins RH Menegussi G Moreira D Rocha JR Pinto MA 《Physics in medicine and biology》1999,44(3):N31-N38
The lack of well established dosimetry protocols for HDR sources is a point of great concern regarding the uniformity of procedures within a particular country and worldwide. The main objective of this paper is to report the results from ten institutions of an intercomparison of calibration procedures for 192Ir HDR sources currently in use in Brazil. The treatment irradiator of one institution was calibrated by a reference system and used by all participants with their own measuring electrometers and ionization chambers under the same experimental conditions. Two methods were used: the calibration jig and the well-type ionization chamber. Each participant was allowed to use their own method and formalism. The results of this exercise were very positive since this was the first time in Brazil that a group of users gathered to share their experience and openly discuss the physical concepts behind the calibration procedures. The results were all within +/-3.0%, except one case where -4.6% was observed and later identified as a problem with the Nk value for x-rays. Though the magnitude of the deviations found was generally acceptable considering the diversity of formalisms currently in use, a proposal is now being prepared to be adopted as a national protocol. The identification of the institutions was left out for the sake of confidentiality. 相似文献
88.
We have investigated the effect of biaxial constraint during glutaraldehyde crosslinking on the equibiaxial mechanical properties of bovine pericardium. Crosslinking of cruciate samples was carried out with: (i) no applied load, (ii) an initial 25 g ( approximately 30 kPa) equibiaxial load, or (iii) an initial 200 g (approximately 250 kPa) equibiaxial load. All loading during crosslinking was done under a defined initial equibiaxial load and subsequently fixed biaxial strain. Load changes during crosslinking were monitored. Mechanical testing and constraint during crosslinking were carried out in a custom-built biaxial servo-hydraulic testing system incorporating four actuators with phase-controlled waveform synthesis, high frame-rate video dimension analysis, and computer-interfaced data acquisition. The paired biaxial stress strain responses under equibiaxial loading at 1 Hz (before and after treatment) were evaluated for changes in anisotropic extensibility by calculation of an anisotropy index. Scanning electron microscopy (SEM) was performed on freeze-fractured samples to relate collagen crimp morphology to constraint during crosslinking. Fresh tissue was markedly anisotropic with the base-to-apex direction of the pericardium being less extensible and stiffer than the circumferential direction. After unconstrained crosslinking, the extensibility in the circumferential direction, the stiffness in the base-to-apex direction, and the tissue's anisotropy were all reduced. Anisotropy was preserved in the tissue treated with an applied 25 g load; however, tissue treated with an applied 200 g load became extremely stiff and nearly isotropic. SEM micrographs correlated well with observed extensibility in that the collagen fibre morphology changed from very crimped (unconstrained crosslinking), to straight (200 g applied load). Biaxial stress-fixation may allow engineering of bioprosthetic materials for specific medical applications. 相似文献
89.
Bozzali M Rocca MA Iannucci G Pereira C Comi G Filippi M 《AJNR. American journal of neuroradiology》1999,20(10):1803-1808
BACKGROUND AND PURPOSE: Previous studies have failed to show significant correlations between the number and extent of T2 spinal cord lesions and the clinical status of multiple sclerosis (MS) patients. We evaluated 1) whether it is feasible to create magnetization transfer-ratio (MTR) histograms of the cervical cord in patients with MS by using two different acquisition schemes, and 2) whether cervical cord MTR histogram metrics were different from those of healthy control subjects and between MS patients with and without locomotor disability. METHODS: We obtained two sets of gradient-echo sequences with and without a saturation pulse from 90 MS patients and 20 sex- and age-matched healthy control subjects. One set consisted of 20 axial, contiguous slices with a thickness equal to 5 mm. The other set consisted of 17 sagittal slices with a thickness equal to 3 mm and an interslice gap equal to 0.3 mm. After image coregistration and removal of tissues around the cervical cord, MTR histograms were created. The average MTR, the peak height, and the peak position of the histograms were measured. All of these measurements were from the whole of the cervical cord, thus including both MS lesions and normal-appearing tissue. RESULTS: When comparing the MTR histograms obtained using axial, contiguous, 5-mm-thick slices, MS patients had significantly lower average cervical cord MTR and peak height than did control subjects. When comparing the MTR histograms obtained using sagittal, 3-mm-thick slices, MS patients also had significantly lower average cervical cord MTR and peak location than did control subjects. Patients with locomotor disability had significantly lower average cord MTR and peak location than those without. CONCLUSION: This study shows that it is feasible to obtain MTR histograms of the cervical cord from MS patients by using different acquisition schemes. Our results also suggest that the assessment of MS cervical cord damage, achieved using MTR histograms, may lead to a better understanding of the clinical manifestations of the disease. 相似文献
90.
A C Pereira D E Saunders V L Doyle J M Bland F A Howe J R Griffiths M M Brown 《Stroke; a journal of cerebral circulation》1999,30(8):1577-1582
BACKGROUND AND PURPOSE: (1)H MR spectroscopy can be used to study biochemical changes occurring in the brain in stroke. We used it to examine the relationship between metabolite concentration (N-acetyl aspartate [NAA], lactate, cholines and creatines), size of infarct, clinical deficit, and 3-month clinical outcome in patients with middle cerebral artery (MCA) territory infarction. METHODS: Thirty-one patients with acute MCA territory infarction were recruited within 72 hours of the onset of symptoms. Single-voxel short echo time stimulated echo acquistion mode spectroscopy was used to obtain metabolite data from the infarct core. Metabolite concentrations were determined with use of variable projection time domain-fitting analysis. Infarct size was determined with T2-weighted images. Patient outcome groups at 3 months were "independent," "dependent," or "dead." RESULTS: All patients (100%; 95% CI 75% to 100%) who had an infarct >70 mL did poorly. Eighteen of 20 patients (90%; 95% CI 68% to 99%) with a core NAA concentration <7 mmol/L did poorly at 3 months, whereas 7 of 11 patients (64%; 95% CI 31% to 89%) with an initial NAA concentration >7 mmol/L did well. Combining these results showed that all patients who had an initial infarct volume >70 mL did poorly, irrespective of the NAA concentration. Of those patients with infarcts <70 mL, those who had a core NAA concentration >7 mmol/L did well (88%; 95% CI 47% to 100%), whereas those with a lower NAA concentration did poorly (80%; 95% CI 44% to 97%). There was no association between other metabolite concentrations and outcome. CONCLUSIONS: Infarct volume and NAA concentration can together predict clinical outcome in MCA infarction in humans. 相似文献