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941.
A group of 11 children with iron deficiency anemia were studied with respect to intestinal structure and function. In six cases there were histological abnormalities of intestinal mucosa in varying degrees consisting of villous damage, increased activity in the crypts, increased lymphoplasmocytic infiltration and changes in the surface epithelium. Ultrastructurally, microvilli lesions, mitochondrial changes and an increase in lysosomes were observed. Relative malabsorption of iron and d-xylose malabsorption were present in a minority of patients. Functional and structural changes were correlated. Our results suggest that these changes are due to impairment of cell metabolism. 相似文献
942.
943.
O L Svendsen U Marslew C Hassager C Christiansen 《European journal of nuclear medicine》1992,19(1):41-46
Two dual energy X-ray absorptiometric (DXA) instruments have recently become commercially available for local bone densitometry: the QDR-1000 (Hologic Inc.) and the DPX (Lunar Radiation Corp.). We report the precision, influence of femoral rotation, correlation and agreement of bone mineral measurements of the proximal femur by these two instruments. In vitro (femur phantom) short-term precision was 1.1%-3.5%, and the long-term precision was 1.2%-3.8%. In vivo (groups of 10 premenopausal and 10 post-menopausal women) short-term precision of duplicate measurements was 1.6%-4.7%, and long-term precision was 1.9%-5.5%. Overall, the precision for Ward's triangle was over 3% and that for the femoral neck and trochanter, 2%-3%. Rotation of a femur phantom produced a statistically significant change in the bone mineral density (BMD) of the femoral neck. Within a clinically relevant range of femoral rotation (20 degrees inward rotation +/- 5 degrees) the coefficient of variation (CV%) increased by a mean factor of 1.1-1.4. Although the correlation (r less than 0.9) between BMD measurements of the proximal femur by the DPX and QDR-1000 in 30 postmenopausal women was high, there was lack of agreement between the two instruments. We found no statistically significant differences between the right and left femur in 30 postmenopausal women. A bilateral femur scan took a mean total time of about 22 min. We conclude that with the introduction of DXA instruments, the precision of bone mineral measurements of the proximal femur has improved. However, for comparability between commercially available DXA instruments, it might be advantageous if units were standardized. 相似文献
944.
Comparison of the heat shock response in ethnically and ecologically different human populations. 总被引:2,自引:0,他引:2 下载免费PDF全文
V N Lyashko V K Vikulova V G Chernicov V I Ivanov K A Ulmasov O G Zatsepina M B Evgen''ev 《Proceedings of the National Academy of Sciences of the United States of America》1994,91(26):12492-12495
In response to heat shock or other metabolic insults, an increased expression of different heat shock proteins (hsps) and, in particular, members of the hsp70 family is observed in human cells. Using two-dimensional electrophoresis, we compared the pattern of hsp70 synthesis in human fibroblast cell lines isolated from two contrasting groups of individuals. The first group was represented by native Turk-men living in the hot desert of Middle Asia; the second group consisted of Russians living in moderate climatic regions of European Russia. This analysis has shown that fibroblasts isolated from Turkmen after severe heat shock exhibited intensive synthesis of all hsps in parallel with synthesis of many other cellular proteins, while only trace synthesis of hsps was observed in the second group (Russians). Surprisingly, Northern analysis of RNA synthesis failed to reveal any differences between the two groups after heat shock treatment. When survival of fibroblasts after severe heat shock treatment was assessed by colony formation assay, the cells of the first group exhibited significantly higher survival rates. 相似文献
945.
Social class, marital status, and cancer of the uterine cervix in England and Wales, 1950-1983. 总被引:2,自引:2,他引:0 下载免费PDF全文
STUDY OBJECTIVE--The aim was to investigate whether trends in mortality from cancer of the cervix uteri by age, marital status, and social class are compatible with current beliefs about the epidemiology of the disease. DESIGN--Data on mortality from cancer of the cervix for single and married women by age and social class were obtained from the Registrar General's Decennial Supplements on occupational mortality for the years 1950-53, 1959-63, 1970-72, and 1979, 1980, 1982, and 1983. Age standardised mortality rates were calculated directly by social class and marital status. SETTING--The data relate to all cases of carcinoma of the cervix reported in England and Wales in the years studied. MAIN RESULTS--There was a marked convergence of mortality between single and married women over the period within every social class grouping examined. The social class differential, however, remained essentially unchanged for both single and married women considered separately. CONCLUSIONS--Trends in mortality by marital status appear to reflect accurately the changes in the pattern of marriage and sexual behaviour that have taken place in the post-war period, whereas the patterns of other risk and protective factors such as screening explain these trends less well. In contrast, it seems likely that factors other than patterns of sexual behaviour and screening operate to maintain the social class differential in England and Wales. 相似文献
946.
947.
M F Beersma J M Galama H A Van Druten W O Renier C J Lucas J G Kapsenberg 《International journal of epidemiology》1992,21(3):583-588
Since 1976, when general immunization against measles was introduced in the Netherlands, all new cases of subacute sclerosing panencephalitis (SSPE) were registered and detailed data about immunization, epidemiology and disease progression were collected on them. Up to 1991, 99 new patients have been registered of which 81 were born in this country and 18 elsewhere. From 1981 onwards, the incidence of SSPE among those born in the Netherlands decreased gradually from 13 cases per year to one case per year. This decrease is attributed to the large scale of immunization against measles. Three SSPE patients had been immunized against measles, all of them without a history of clinical measles. Epidemiology and risk factors of SSPE did not differ from those reported in other countries. An exceptional cluster of four patients in one town, who had measles in the same year, is reported. Progression of SSPE appeared to be age related. A total of 28 patients was treated with Inosiplex; no significant effect on survival in stage 3 of the disease was found. 相似文献
948.
949.
O Dammann J C Commentz J M Valdueza L Christante K H Bentele 《Klinische P?diatrie》1991,203(6):439-447
Four cases of hypothalamic hamartoma leading to gelastic epilepsy, precocious puberty and behavioural disorders are reported. Cerebral neuroradiologic examinations revealed a tumor-like mass attached to the hypothalamus in the region of the mamillary bodies in all cases. Precocious puberty developed in the two girls at 4 and 13 months but in neither of the two boys, who both suffered behaviour disturbances in the form of aggressive outbursts. A total resection of the tumors of both boys led to histologic confirmation of hamartoma. One boy was free of seizures upon follow-up, whereas seizure frequency in the other boy was reduced, while his aggressivity increased. The cases are discussed in context of current therapeutic conceptions of gelastic epilepsy and central precocious puberty. 相似文献
950.
Adult-to-adult living donor liver transplantation using extended right lobe grafts. 总被引:11,自引:0,他引:11 下载免费PDF全文
C M Lo S T Fan C L Liu W I Wei R J Lo C L Lai J K Chan I O Ng A Fung J Wong 《Annals of surgery》1997,226(3):261-270
OBJECTIVE: The authors report their experience with living donor liver transplantation (LDLT) using extended right lobe grafts for adult patients under high-urgency situations. SUMMARY BACKGROUND DATA: The efficacy of LDLT in the treatment of children has been established. The major limitation of adult-to-adult LDLT is the adequacy of the graft size. A left lobe graft from a relatively small volunteer donor will not meet the metabolic demand of a larger recipient. METHODS: From May 1996 to November 1996, seven LDLTs, using extended right lobe grafts, were performed under high-urgency situations. All recipients were in intensive care units before transplantation with five having acute renal failure, three on mechanical ventilation, and all with hepatic encephalopathy. The median body weight for the donors and recipients was 58 kg (range, 41-84 kg) and 65 kg (range, 53-90 kg), respectively. The body weights of four donors were less than those of the corresponding recipients, and the lowest donor-to-recipient body weight ratio was 0.62:1. The extended right lobe graft was chosen because the left lobe volume was <40% of the ideal liver mass of the recipient. RESULTS: Median blood loss for the donors was 900 mL (range, 700-1600 mL) and hospital stay was 19 days (range, 8-22 days). Homologous blood transfusion was not required. Two donors had complications (one incisional hernia and one bile duct stricture) requiring reoperation after discharge. All were well with normal liver function 5 to 10 months after surgery. The graft weight ranged from 490 g to 1140 g. All grafts showed immediate function with normalization of prothrombin time and recovery of conscious state of the recipients. There was no vascular complication, but six recipients required reoperation. One recipient died of systemic candidiasis 16 days after transplantation and 6 (86%) were alive with the original graft at a median follow-up of 6.5 months (range, 5-10 months). CONCLUSIONS: When performed by a team with experience in hepatectomy and transplantation, LDLT, using an extended right lobe graft, can achieve superior results. The technique extends the success of LDLT from pediatric recipients to adult recipients and opens a new donor pool for adults to receive a timely graft of adequate function. 相似文献