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991.
The temporal changes in childhood and adolescent cancer survival in Sweden 1960-1984 were analyzed. Complete follow-up through 1986 of 6,262 patients younger than 20 years at diagnosis revealed that the overall 5-year survival rates increased from 36.1 to 65.7% in males and from 43.6 to 73.6% in females. The temporal trends differed markedly between age groups and tumour sites and types. Over the study period, 5-years, survival for testicular cancer increased from 46.9 to 87.2%, kidney cancer, predominantly Wilms' tumour from 35.5 to 77.1% (with a higher rate of 89.1% in 1975-1979), Hodgkin's disease from 61.2 to 91.9%, non-Hodgkin's lymphoma from 32.5 to 76.6%, and all leukemias from 8.9 to 58.7%. Only a moderate improvement was noted for tumours of the bone, muscle and connective tissue, and survival rates for tumours of the nervous system remained largely unchanged. Our data reflect the remarkable therapeutic improvements that have occurred for cancer in the young and indicate that these improvements have rapidly become available in Sweden.  相似文献   
992.
993.
The preoperative diagnosis of diffuse heterotopic submucosal cystic malformation of the stomach is very difficult to make with upper gastrointestinal (GI) series or endoscopy. We report a case of submucosal cysts associated with an early gastric carcinoma in which ultrasonography (US) and endoscopic ultrasonography (EUS) were very useful in the preoperative diagnosis.  相似文献   
994.
995.
The dynamics of the speed of transcranial propagation of ultrasonic impulses has been established in humans. The possibility of detecting the changes in mechanical state of intracranial structures by dynamic measurement of the time of transcranial propagation of ultrasonic impulses (TUPT) has been ascertained for 10 healthy persons and 11 patients with different neurological pathology. The cerebrospinal fluid pressure (CSFP) was simultaneously monitored for 4 of the patients. Spontaneous fluctuations in TUPT and the changes caused by jugular veins, inferior vena cava compression, hyperventilation and temporary retention of breathing were detected for all investigated subjects. Spontaneous TUPT changes in the range of 0.25-0.85 x 10(-4) of initial mean value, which are related with cardiac and respiratory cycles, have been found in healthy persons while in patients they ranged from 0.07 x 10(-4) to 4.5 x 10(-4) of mean time. In healthy persons bilateral jugular vein compression leads to a decrease in TUPT by 1.8-3.0 x 10(-4), while the compression of inferior vena cava gives an increase in TUPT by 1.6-2.6 x 10(-4). Changes in TUPT during these maneuvers in neurological patients were found to be of different amplitude and direction. The rise of CSFP by 8.4-20.2 mmHg (mean 12.4 mmHg) was observed in 4 investigated patients during the compression of jugular veins or during the inferior vena cava compression, while the changes in TUPT obtained during each of such maneuvers were of opposite character. The results suggest that dynamic evaluation of acoustic impedance of intracranial system reflects the changes in the mechanical state of brain parenchyma.  相似文献   
996.
We describe the clinical and pathological findings of the hemolytic uremic syndrome (HUS) in two children with human immunodeficiency virus (HIV) infection. Both patients presented with microangiopathic hemolytic anemia, thrombocytopenia, and subsequently developed renal failure. The diagnosis of HUS was confirmed by renal histopathology in both patients. None of these children presented with bloody diarrhea, evidence of circulating antibody response to Escherichia coli O157 lipopolysaccharide, or other known risk factors for HUS, except for the presence of HIV infection. Each patient was treated with intravenous plasma infusion and renal replacement therapy. Their clinical course was characterized by non-oliguria and lack of significant hypertension throughout the acute phase of the disease. Despite these favorable clinical parameters, both patients developed end-stage renal failure. The etiology of this atypical HUS characterized by poor renal survival remains unknown and the role of HIV infection in its pathogenesis, although possible, is unclear. Received March 5, 1996; received in revised form and accepted October 15, 1996  相似文献   
997.
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   
998.
999.
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   
1000.
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   
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