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Analysis of apparent bone mineral density (BMD) in the lumbar spine is commonly based on anteroposterior (AP) scanning using dual-energy X-ray absorptiometry (DXA). Although not widely used, clinically important information can also be derived from lateral scanning. Vertebral bone density, and therefore strength, can may vary in different subregions of the vertebral body. Therefore, subregional BMD measurements might be informative about fracture risk. However, the intrarater and interrater precision of in vivo subregional BMD assessments from lateral DXA remains unknown. Ten normal, young (mean: 24 yr) and 10 older (mean: 63 yr) individuals with low BMD were scanned on one occasion using an AP/lateral sequence. Each lateral scan was reanalyzed six times at L2 by three raters to determine the intrarater and interrater precision in selecting seven regions of interest (subregions). Precision was expressed using percentage coefficients of variation (% CV) and intraclass correlation coefficients (ICC). Intrarater precision ranged from ICC(1,1) 0.971 to 0.996 (% CV: 0.50-3.68) for the young cohort and ICC(1,1) 0.934 to 0.993 (% CV: 1.46-5.30) for the older cohort. Interrater precision ranged from ICC(2,1) 0.804 to 0.915 (% CV: 1.11-2.35) for the young cohort and ICC(2,1) 0.912 to 0.984 (% CV: 1.85-4.32) for the older cohort. Scanning a subgroup of participants twice with repositioning was used to assess short-term in vivo precision. At L2, short-term in vivo precision ranged from ICC(1,1) 0.867 to 0.962 (% CV: 3.38-9.61), at L3 from ICC(1,1) 0.961 to 0.988 (% CV: 2.02-5.57) and using an L2/L3 combination from ICC(1,1) 0.942 to 0.980 (% CV: 2.04-4.61). This study demonstrated moderate to high precision for subregional analysis of apparent BMD in the lumbar spine using lateral DXA in vivo.  相似文献   
3.
Biochemical data were studied in 18 patients with severe acute pancreatitis receiving lipid associated with total parenteral nutrition. The mean nonprotein energy intake was 30 kcal/kg/day, with 34-70% of the nonprotein calories as lipid. These parameters were no different between patients who survived and those who died. The mean sum of Ranson criteria was significantly higher in patients who died as compared with those who survived. Plasma triglycerides, glucose, albumin, and the amount of insulin supplementation were related to the severity of the disease and to the outcome. Persistent hypertriglyceridemia, hyperglycemia, hypoalbuminemia, and higher insulin requirements were observed in patients who died in comparison with those who survived and this appeared to be an index of fatal outcome. These abnormalities reflect in part an inability to utilize nonprotein energy, because the measured energy expenditure in relation to intake was lower in the patients who died, despite comparable intakes and expected energy expenditures.  相似文献   
4.
汪南华  王锐  冷宗康  彭司勋 《药学学报》1990,25(12):920-925
缩氨基硫脲类化合物有抗肿瘤、抗病毒和抗菌等多种药理活性。Barret等首次报道了乙二醛二缩氨基硫脲(Ⅰ)的抗疟活性。Klayman等研究了缩  相似文献   
5.
We present a case of a newborn with congenital rickets and radiographic evidence of secondary hyperparathyroidism in which the infant's mother had severe, longstanding untreated renal insufficiency.  相似文献   
6.
One hundred and twenty-nine jaundiced patients were operated upon for the relief of benign and malignant bile duct obstruction during a 10-year period, 1977-86. The overall mortality was 4.7 per cent but increased to 9.1 per cent in patients with a serum bilirubin greater than 300 mumol/l. In all, 46.5 per cent of patients had a rise in postoperative creatinine but renal dysfunction occurred in only 4.7 per cent. Wound infection developed in 3.1 per cent of patients and appeared unrelated to infected bile; 3.9 per cent of patients were treated for postoperative septicaemic episodes. The low morbidity and mortality observed suggests that preoperative biliary drainage need not be considered in routine surgical practice if simple measures to maintain urine flow and prevent postoperative sepsis are used.  相似文献   
7.
Many centers are reluctant to use older donors (>44 years) for adult right-lobe living donor liver transplantation (RLDLT) due to concerns about possible increased morbidity in donors and poorer outcomes in recipients. Since 2000, 130 adult RLDLTs have been performed at our institution. Recipients were divided into those who received a right lobe graft from a donor ≤age 44 (n = 89, 68%; median age 30) and those who received a liver graft from a donor age >44 (n = 41, 32%; mean age 52). The two donor and recipient populations had similar demographic and operative profiles. With a median follow-up of 29 months, the severity and number of complications in older donors were similar to those in younger donors. No living donor died. Older donor allografts had initial allograft dysfunction compared to younger donors. Complication rates were similar among recipients in both groups but there was a higher bile duct stricture rate with older donor grafts (27% vs. 12%; p = 0.04). One-year recipient graft survival was 86% for older donors and 85% for younger donors (p = 0.95). Early experience with the use of selected older adults (>44 years) for RLDLT is encouraging, but may be associated with a higher rate of biliary complications in the recipient.  相似文献   
8.
Metrazol enhanced the penetration of two proteins (125I human serum albumin and horseradish peroxidase), and the anticancer agent, razoxane, into the central nervous system of anaesthetized rats. Penetration was increased throughout the whole brain. With the exception of the bladder, no peripheral tissue was affected. The increase in brain permeability was temporary and reversed within 4 hours; brain levels of drug and protein were increased by up to three times.[/p]  相似文献   
9.
BACKGROUND. Serum carcinoembryonic antigen level is raised in 80% of patients undergoing colonic resection for cancer. Subsequent elevation in the follow-up period may precede signs and symptoms as an indicator of recurrent disease. there is little evidence that "classical" follow up of patients in the general surgical outpatient clinic improves either survival or quality of life. Regular carcinoembryonic antigen level estimation requested by the general practitioner, allied to day-case colonoscopic surveillance may be a more rational approach. AIM. A study was undertaken to investigate the relationship between raised carcinoembryonic antigen level and the recurrence of colorectal cancer in patients following a curative primary resection. METHOD. Retrospective analysis was carried out on the notes of 125 patients who had attended a dedicated hospital colorectal follow-up clinic between 1988 and 1992. Carcinoembryonic antigen level data were obtained by subsequent examination of the University of Edinburgh Department of Clinical Chemistry (immunoassay section) carcinoembryonic antigen database. RESULTS. A single carcinoembryonic level result of more than 100 ul-1 (normal range less than 60 ul-1) was found to be a highly sensitive (87%), specific (89%), and accurate (88%) indicator of recurrent disease. Raised carcinoembryonic antigen level preceded symptoms in 72% of patients with recurrence of colorectal cancer. CONCLUSION. Sequential laboratory estimation of carcinoembryonic antigen level organized by the general practitioner may represent an accurate method of detecting recurrent colorectal disease. Hospital review could be limited to colonoscopic surveillance and restaging of patients referred with evidence of recurrent disease.  相似文献   
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