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91.
AM Larson GC Chan CF Wartelle JP McVicar RL Carithers GM Hamill KV Kowdley 《Canadian Metallurgical Quarterly》1997,26(6):1406-1409
There is controversy about the frequency of and risk factors for infectious complications of percutaneous liver biopsy in liver transplant recipients. The aim of this study was to identify the incidence and nature of complications associated with liver biopsy after orthotopic liver transplantation (OLT), with particular emphasis on infection. The medical records of all patients undergoing OLT between January 1990 and August 1994 were reviewed retrospectively to identify complications requiring hospitalization within one week of percutaneous liver biopsy. The nature and severity of complications were recorded and possible risk factors for infectious complications were examined. One hundred ninety-eight patients underwent 1,136 percutaneous liver biopsies. There were eleven complications (0.96%), including as follows: 7 infections, 3 bleeding episodes, and 1 vasovagal reaction. Infections after percutaneous liver biopsy included fever and bacteremia (n = 6), and fever without bacteremia (n = 1). All infections developed only in patients with underlying biliary tract abnormalities; the frequency of infection was higher (9.8%) in patients with choledochojejunostomy when compared with those with choledochocholedochostomy (1.4%). Bacteremia was more likely caused by skin flora in patients with choledochocholedochostomy (CDC) and by enteric bacteria in patients with choledochojejunostomy (CDJ). All infections were treated successfully with parenteral antibiotics. We conclude that biliary tract abnormalities are the primary risk factors for infection after percutaneous liver biopsy, although the risk is higher in patients with CDJ than with CDC. These data support the use of antibiotic prophylaxis before percutaneous liver biopsy in OLT recipients with biliary tract abnormalities. 相似文献
92.
AS Carman SS Kuan GM Ware PP Umrigar KV Miller HG Guerrero 《Canadian Metallurgical Quarterly》1996,79(2):456-464
Immunoaffinity column-based sample preparation procedures for determination of aflatoxins B1, B2, G1, and G2 in several food matrixes and aflatoxin M1 in milk have been automated by using flexible automation, or robotics. Components used to assemble the system were purchased commercially or developed and built in-house. A liquid-level sensor developed in-house to assist elution of the immunoaffinity column is described. After immunoaffinity column cleanup, aflatoxins are separated by reversed-phase liquid chromatography and determined by fluorescence without derivatization. Mean recoveries of aflatoxins B1, B2, and G1 added to corn and nuts at 9-36 ng/g total aflatoxins were > 85% (coefficient of variation [CV] = 16%). Recoveries of aflatoxin G2 averaged 50% (CV = 28%). Recoveries of aflatoxin M1 added to milk at 0.12-0.50 ng/mL averaged 78% (CV = 19%). The ability of the automated system to reproduce its results is demonstrated by the fact that the CV of replicate assays is generally better than 10%. Comparability between the automated procedure and the AOAC official method is demonstrated. 相似文献
93.
M Naumann KV Toyka B Mansouri Taleghani J Ahmadpour K Reiners H Bigalke 《Canadian Metallurgical Quarterly》1998,65(6):924-927
The objective was to evaluate whether removal of neutralising antibodies potentially resensitises a secondary non-responder to botulinum neurotoxin A (BoNT/A). Neutralising antibodies directed against BoNT/A are produced during long term treatment with BoNT/A-hemagglutinin complex in up to 10% of patients with cervical dystonia. These patients become secondary non-responders. Other serotypes of BoNT are not yet generally available and may also bear the risk of inducing antibody formation. Plasma exchange (PE) (one treatment cycle) and immunoadsorption on a protein A column (IA-PA; three treatment cycles) was employed over 15 months to remove neutralising antibodies from a severely disabled secondary non-responder with cervical dystonia. After plasma exchange or IA-PA, BoNT/A was reinjected. Antibodies were measured with a sensitive functional toxin neutralising test. Repeated use of plasma exchange and IA-PA depleted neutralising antibodies to below the detection limit and subsequently allowed successful BoNT/A injection into dystonic muscles. No serious side effects were found related to the depletion of IgG. In conclusion PE or IA-PA performed before BoNT/A readministration may provide an alternative strategy in treating selected secondary non-responders who are severely disabled. 相似文献
94.
KB Nazarian SZ Simonian BA Kazarian P Perez F Climent 《Canadian Metallurgical Quarterly》1995,60(5):746-753
Neuron-specific enolase and phosphoglycerate mutase with specific activities of 106 and 215 U/mg, respectively, have been purified from human brain. Hydrophobic chromatography for enolase and blue Sepharose affinity chromatography for phosphoglycerate mutase were used as the last steps of purification. A heterobifunctional complex with fully preserved enolase and phosphoglycerate mutase activities was synthesized with the use of a bifunctional reagent, N-succinimidyl 3-(2-pyridyldithio)propionate. Autoantibodies to the conjugate will be used for identifying the bienzymatic complex in vivo. 相似文献
95.
96.
The levels of hormones of hypothalamo-hypophyseal-adrenal system were measured in 14 10-14 year old children with infantile cerebral paralysis (ICP) with central catecholaminergic motor insufficiency. Contents of adrenocorticotropic hormone (ACTH), hydrocortisone (HC), somatotropic hormone, prolactin (P) were examined before and during Nacome administration (62.5 mg once daily in the morning). 110 patients of the same age with ICP and 18 children with acquired encephalopathy (EP) formed the control group. The elevations of ACTH, HC and P were revealed in spastic forms of ICP. Meanwhile nearly normal hormonal levels were observed in hyperkinetic forms of ICP and EP. The more pronounced effect was noted in "dopamine-dependent" children in which the drug's administration resulted in normalization of clinical and biochemical indices. Hyperkinetic phenomena revealed the connection between the character of neuromotor dyskinesias and the state of hypothalamo-hypophyseal-adrenal axis which is regulated by dopamine. The data obtained show hypofunction of dopaminergic neurotransmitter cerebral systems in patients with ICP that plays important pathogenetic role in development of disease with systemic manifestations. 相似文献
97.
The results of the treatment of 316 patients with various injuries of abdomen are summarized. 144 (45.6%) of the patients were operated on vital indications (internal bleeding, peritonitis). Additional instrumental examination was necessary in 172 (54.4%) of the patients. Urgent diagnostic laparoscopy was performed in 118 of them. This procedure is indicated in patients with the absence of the symptoms of "acute abdomen" hospitalised in less than 2 hours from the moment of penetrating injury. It is also indicated in case of a doubtful diagnosis in a blunt injury of abdomen, and in alcoholic intoxication. Three groups of the patients were distinguished: 1) patients with indications for urgent surgery (38.1%); 2) patients with indications for conservative treatment (17.8%); 3) patients with indications for out-patient follow-up (44.1%). This policy made it possible to decrease the number of diagnostic laparotomies to 11%, the period of limited disability by 5.8 + 0.3 days, decrease lethality to 6%. 相似文献
98.
3'-Phosphoadenosine-5'-phosphosulfate (PAPS) synthase is a bifunctional protein consisting of an NH2-terminal APS kinase and a COOH-terminal ATP sulfurylase. Both catalytic activities require ATP; the APS kinase domain involves cleavage of the beta-gamma phosphodiester bond of ATP, whereas the ATP sulfurylase domain involves cleavage of the alpha-beta phosphodiester bond of ATP. Previous mutational studies have suggested that beta-gamma phosphodiesterase activity involves a highly conserved NTP-binding P-loop motif located in the adenosine-5'-phosphosulfate kinase domain of PAPS synthases. Sequence alignment analysis of PAPS synthases and the superfamily of TagD-related nucleotidylyltransferases revealed the presence of a highly conserved HXGH motif in the ATP sulfurylase domain of PAPS synthases, a motif implicated in the alpha-beta phosphodiesterase activity of cytidylyltransferases. Thus, site-selected mutagenesis of the HXGH motif in the ATP sulfurylase domain of human PAPS synthase (amino acids 425-428) was performed to examine this possibility. Either H425A or H428A mutation produced an inactive enzyme. In contrast, a N426K mutation resulted in increased enzymatic activity. A G427A single mutant resulted in only a modest 30% reduction in catalytic activity, whereas a G427A/H428A double mutant produced an inactive enzyme. These results suggest an important role for the HXGH histidines in the ATP sulfurylase activity of bifunctional PAPS synthase and support the hypothesis that the highly conserved HXGH motif found in the ATP sulfurylase domain of PAPS synthases is involved in ATP binding and alpha-beta phosphodiesterase activity. 相似文献
99.
TARALD O. KVÅLSETH 《国际生产研究杂志》2013,51(4):441-454
This paper presents some quantitative measures of job variety based on entropy statistics of information theory and on a modification of the Turner-Lawrence measure. By means of the psychophysical scaling technique of magnitude estimation, subjective judgements of variety for a number of different job situations were obtained from a total of 42 subjects. Power models or linear models between perceived variety and its physical correlates were found to explain up to 99% of the variation in perceived variety. Since job variety is generally considered to have a significant influence on motivation and job satisfaction, such quantitative models may possess practical utility for job design and for systematic programmes of job enlargement or enrichment. 相似文献
100.
TARALD O. KVÅLSETH 《国际生产研究杂志》2013,51(5):427-435
This experimental study analysed the effects of the complexity (entropy) of a repetitive tusk on the human looming function for the task. The results from 20 subjects revealed that the task entropy had a significant influence on the relationship between the performance (cycle time) and practice (the number of repetitions or cycle number). The model parameters for this relationship were found to be significantly and linearly related to the task entropy, the nominal rate of which varied within the maximum range of 0·9·to 6.1 bits/s 相似文献