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21.
Psychological functioning and adjustment to dialysis were assessed in the families of 60 children and adolescents undergoing
chronic dialysis. Sociodemographic factors, treatment variables, health status and satisfaction with health care provision
were also measured. Correlation analyses identified a number of important factors associated with poor adjustment to dialysis
and/or anxiety and depression in children and parents. Particularly at risk are parents in lower socioeconomic status households,
parents with large families, parents with limited support and parents of young children. Children were more at risk where
there was greater functional impairment caused by illness.
Received: 10 December 1997 / Revised: 8 March 1999 / Accepted: 16 March 1999 相似文献
22.
J. W. Lumley M.B. B.S. F.R.A.C.S. G. A. Fielding M.B. B.S. F.R.C.S. F.R.A.C.S. M. Rhodes M.A. M.D. F.R.C.S. L. K. Nathanson M.B. C.H.B. F.R.A.C.S. S. Siu M.B. B.S. F.R.A.C.S. R. W. Stitz R.F.D. M.B. B.S. F.R.C.S. F.R.A.C.S. 《Diseases of the colon and rectum》1996,39(2):155-159
PURPOSE: To audit the development and outcomes of laparoscopic colorectal surgery at the Royal Brisbane Hospital. METHODS: Since July 1991, laparoscopic-assisted colectomy for benign and malignant colorectal disease has been performed on more than 300 patients at the Royal Brisbane Hospital. This paper summarizes the outcome for the first 240 patients who underwent a laparoscopic colorectal procedure. All laparoscopic data were collected prospectively, and for selected studies, data were compared with open surgical controls. RESULTS: Nineteen patients required open conversion (7.9 percent). There was a significant decrease in wound infection rates in patients having a laparoscopic-assisted colectomy (3.6 percent) compared with historical controls (7.9 percent) (P<0.05; chisquared). There were five anastomotic leaks, five laparotomies for postoperative adhesive obstruction, and four perioperative deaths. A total of 103 patients had a procedure for colorectal cancer. Of the 79 potentially curative procedures, there have been 5 (6.3 percent) recurrences to date. CONCLUSION: The overall morbidity and mortality in this series seem to be acceptable compared with that of open procedures. 相似文献
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24.
Effects of site-directed mutagenesis at residues cysteine-31 and cysteine-184 on lecithin-cholesterol acyltransferase activity. 总被引:3,自引:1,他引:2
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O L Francone C J Fielding 《Proceedings of the National Academy of Sciences of the United States of America》1991,88(5):1716-1720
Native lecithin-cholesterol acyltransferase (LCAT; phosphatidylcholine-sterol acyltransferase; phosphatidylcholine:sterol O-acyltransferase, EC 2.3.1.43) protein, and LCAT in which either or both of the enzyme free cysteines had been replaced with glycine residues by site-directed mutagenesis, has been expressed in cultured Chinese hamster ovary cells stably transfected with the human LCAT gene. The mass of LCAT secreted, determined by immunoassay, did not differ in the native and mutant species. LCAT specific activity was also unchanged in the mutant species. In particular, the cysteine-free double mutant, in which Cys-31 and Cys-184 had both been replaced, was fully active in the synthesis of cholesteryl esters. This result is not consistent with a catalytic role for LCAT free cysteine residues. The classical inhibitor of LCAT activity, 5,5'-dithiobis(2-nitrobenzoic acid) (DTNB), which strongly (89%) inhibited the native enzyme, had partial (45%) inhibitory activity with mutant enzyme species containing a single -SH residue, while the double mutant was not significantly inhibited by DTNB. These data are interpreted to suggest that Cys-31 and Cys-184 are vicinal both to each other and to the "interfacial binding site" at residues 177-182, and that DTNB exerts its effect by steric inhibition. 相似文献
25.
N B Ress J R Hailey R R Maronpot J R Bucher G S Travlos J K Haseman D P Orzech J D Johnson M R Hejtmancik 《Toxicological sciences》2003,71(2):198-206
Citral, a widely used natural ingredient, is added to foods and cosmetics as a flavoring and fragrance agent. Male and female F344/N rats and B6C3F1 mice were exposed to microencapsulated citral in the feed for 14 weeks or two years. All studies included untreated and vehicle control groups. In the 14-week studies, rats and mice were given diets containing 3,900, 7,800, 15,600, or 31,300 ppm citral. In rats, food consumption was reduced in the two highest dose groups. In mice an apparent increase in food consumption was observed, but was due to mice scattering the feed. Body weights of all treated animals were less than controls. All rats and four male mice were killed moribund in the high dose groups. In rats, forestomach and kidney lesions were observed. At the higher doses, lesions observed in the bone marrow, testes, and thymus in rats and in the ovary in mice were considered related to inanition and resultant moribundity. In the two-year studies, rats were exposed to 1,000, 2,000, or 4,000 ppm citral. Body weights were reduced in the 4,000 ppm rats. Mice were exposed to 500, 1,000, or 2,000 ppm citral. Body weights in the 1,000 and 2,000 ppm groups were reduced. No neoplasms were attributed to citral in rats or mice. Malignant lymphoma occurred with a positive trend and was significantly greater than controls in female mice in the 2,000 ppm group. However, the incidences were within the NTP historical control range and could not be clearly related to citral administration. 相似文献
26.
Uptake of individual fatty acids into adipose tissue in relation to their presence in the diet 总被引:4,自引:0,他引:4
Summers LK Barnes SC Fielding BA Beysen C Ilic V Humphreys SM Frayn KN 《The American journal of clinical nutrition》2000,71(6):1470-1477
BACKGROUND: The fatty acid composition of adipose tissue triacylglycerol reflects, but is not identical to, the fatty acid composition of the habitual diet. OBJECTIVE: We investigated whether the fatty acid composition of adipose tissue is explained by differences between fatty acids in early storage in adipose tissue after a meal. DESIGN: Nine healthy men ate a meal containing several fatty acids. Blood samples were taken for 6 h after the meal from an arterialized hand vein and a vein draining the anterior abdominal subcutaneous adipose tissue. RESULTS: Net storage of fatty acids in adipose tissue occurred between 1 and 4 h after the meal. In relation to the amount fed, storage of fatty acids differed (P < 0. 01) between classes (n-3 polyunsaturated < saturated < n-6 polyunsaturated < monounsaturated); oleic acid was stored in the greatest amounts. These differences agreed closely with published data, except for n-3 polyunsaturated fatty acids. The only individual metabolic step at which significant differences between fatty acids was shown was incorporation of fatty acids into chylomicron triacylglycerol. Differences between fatty acids in rate of extraction from chylomicron triacylglycerol and net uptake into adipose tissue in the postprandial period were significant (P < 0. 01), but not when expressed in relation to proportions in chylomicron triacylglycerol. CONCLUSIONS: The characteristic fatty acid pattern of adipose tissue may predominantly reflect the early metabolic handling of different fatty acids. Adipose tissue uptake of n-3 polyunsaturated fatty acids is slow in relation to that of other fatty acids. 相似文献
27.
Mamta Behl Susan A. Elmore David E. Malarkey Milton R. Hejtmancik Diane K. Gerken Rajendra S. Chhabra 《Toxicology》2013,303(1):84-94
Styrene acrylonitrile (SAN) trimer is a by-product in the production of acrylonitrile styrene plastics. Following a report of a childhood cancer cluster in the Toms River section of Dover Township, New Jersey, SAN Trimer was identified as one of the groundwater contaminants at Reich Farm Superfund site in the township. The contaminants from the Reich Farm site's ground water plume impacted two wells at the Parkway well field. The National Toxicology Program (NTP) studied the toxicity and carcinogenicity of SAN Trimer in rats exposed during their perinatal developmental period and adulthood. The chronic toxicity and carcinogenicity studies in F344/N rats were preceded by 7- and 18-week perinatal toxicity studies to determine the exposure concentrations for the 2-year studies. Subsequently, Fisher 344 pregnant dams were exposed to SAN Trimer containing diet at 400, 800, or 1600 ppm concentrations during gestation, nursing and weaning periods of offspring followed by two year of adult exposures to both male and female pups. There was no statistically significant evidence of carcinogenic activity following SAN-Trimer exposure; however, rare neoplasms in the brain and spinal cord were observed in males and to lesser extent in female rats. These incidences were considered within the range of historical background in the animal model used in the current studies. Therefore, the presence of a few rarely occurring CNS tumors in the treated groups were not judged to be associated with the SAN Trimer exposure. The major finding was a dose-related peripheral neuropathy associated with the sciatic nerves in females and spinal nerve roots in males and females thereby suggesting that SAN Trimer is potentially a nervous system toxicant. 相似文献
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