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排序方式: 共有3549条查询结果,搜索用时 140 毫秒
861.
D Cruickshank LN Sansom ME Veronese B Mojarrabi ME McManus X Zhu 《Canadian Metallurgical Quarterly》1993,191(1):295-301
A cDNA encoding an isoenzyme of rat liver aryl sulphotransferase was isolated from a rat liver bacteriophage Lambda gt 11 library by the polymerase chain reaction technique. The resulting cDNA was functionally expressed in COS-7 cells and characterised by determining the sulphating capacity of the cells with a range of substrates. The COS-expressed enzyme catalysed the sulphation of both phenol and dopamine with Kms of the same order as those obtained for the high affinity isozyme in rat liver cytosol, while low activity was observed with tyrosine methyl ester. The common food additive vanillin was also a good substrate for sulphate conjugation. The sulphation of vanillin catalysed by the COS-expressed enzyme was consistent with a single enzyme system, in contrast, the kinetics of the reaction catalysed by cytosolic sulphotransferase indicated that vanillin was sulphated by more than one isozyme. 相似文献
862.
863.
OBJECTIVE: The purpose of this study was to determine the pattern of adjustment over time of a cohort of children with newly diagnosed diabetes compared with a cohort of peer-selected children without diabetes over the first 2 years after the diagnosis of insulin-dependent diabetes mellitus (IDDM). RESEARCH DESIGN AND METHODS: Children (n = 89 with IDDM, n = 53 without IDDM) ages 8-14 years were studied with the Children's Depression Inventory, State-Trait Anxiety Inventory for Children, Child and Adolescent Adjustment Profile, Self-Perception Profile for Children, and a general health scale. Initial data were collected within 6 weeks of the diagnosis of IDDM and at 3, 6, 12, and 24 months thereafter. RESULTS: There were no demographic differences between the two groups. Initially, children with diabetes were more depressed, more dependent, and more withdrawn than their peers. By 1 year postdiagnosis, there were no significant differences in psychosocial status between the two groups. By 2 years postdiagnosis, depression, dependency, and withdrawal were significantly higher in children with diabetes than in their peers without IDDM. Self-perceived competence remained similar between the two groups at all time points. CONCLUSIONS: After an initial period of adjustment, children with IDDM have equivalent psychosocial status to children without IDDM, but by 2 years after diagnosis, they have experienced twice the amount of depression and adjustment problems as their peers. Interventions should be aimed at this critical period between 1 and 2 years postdiagnosis. 相似文献
864.
AA Brooks MR Johnson ME Pawson A Thomas LK Phelan HI Abdalla 《Canadian Metallurgical Quarterly》1996,11(12):2724-2731
Currently, there is a paucity of data describing endometrial growth, with most studies concentrating on endometrial thickness immediately prior to implantation or embryo transfer. This study looked at the individual and combined growth profiles of 67 volunteers receiving three different hormone replacement regimens. Each treatment regimen was in excess of that considered necessary for optimal growth, and all promoted an endometrial thickness that would be considered satisfactory for embryo transfer. Three patterns of growth were identified, but overall there was a decrease in the rate of endometrial growth with duration of treatment. As expected, analysis of variance did not show a significant difference between the mean growth profiles for the three hormone replacement regimens. The correlation (r = 0.45, P < 0.0001) between rank order on day 3 and day 10 of treatment indicates that interim analysis during early treatment cannot accurately predict later thickness, but a doubling of endometrial thickness can be expected in most cases. A relationship between endometrial thickness and either the treatment dose or serum concentrations of oestradiol was not found. These findings suggest that manipulation of endometrial growth is not possible by adjustment of either the treatment dose or serum concentration. The findings indicate that treatment beyond 12 days does not promote either a clinically significant increase in endometrial thickness of an excessive thickness, suggesting that maintenance of an oocyte recipient in a pseudo-follicular phase is unlikely to be disadvantageous to implantation. 相似文献
865.
The reactions of 221 women to their place of delivery (state or private hospital), type of delivery (vaginal or Caesarean) and associated obstetrical interventions were explored by means of a structured interview conducted at 3 months postpartum. Women were randomly selected from the birth records of three cultural groups residing in the municiple area of Johannesburg, South Africa: White (n = 72), Indian (n = 79) and Mixed cultural origin (n = 78). The type of birth experienced by women differed in the cultural groups examined. While most women experienced positive emotional reactions to birth many also expressed a variety of negative reactions. The differences in care experienced by women in the present study reflect the impact of the two systems of care, private and state, that are available to women in South Africa. 相似文献
866.
P Papageorgiou F Anselme CJ Kirchhof K Monahan CA Rasmussen LM Epstein ME Josephson 《Canadian Metallurgical Quarterly》1997,96(6):1893-1898
BACKGROUND: Atrial fibrillation (AF) is due to reentry, and its incidence has been shown to decrease after dual-site atrial or biatrial pacing. We investigated whether a simpler pacing approach via the distal coronary sinus (CSd) could eliminate AF inducibility by high right atrial (HRA) extrastimuli (APDs). We based our hypothesis on our previous observation that AF inducibility by HRA APDs was associated with conduction delays to the posterior triangle of Koch, whereas AF was never induced with CSd APDs, which were associated with minimal intra-atrial conduction delays. METHODS AND RESULTS: Programmed electrical stimulation was performed from the high right atrium and CSd, and bipolar recordings were obtained from the high right atrium, His bundle, posterior triangle of Koch, and coronary sinus. In 13 patients (age, 44+/-18 years), AF was reproducibly induced with a critically timed HRA APD (220+/-22 ms) delivered during HRA pacing. AF was not induced in any of the patients when HRA APDs were delivered during CSd pacing at the same critical coupling intervals. Coronary sinus APDs delivered during HRA pacing also were not associated with AF induction. The APD coupling interval measured at the posterior triangle of Koch during CSd pacing was significantly prolonged compared with the one measured during HRA pacing and AF induction (381+/-58 versus 263+/-37 ms; P<.0001). CONCLUSIONS: We propose that CSd pacing suppresses the propensity of HRA APDs to induce AF by limiting their prematurity at the posterior triangle of Koch and not allowing local conduction delay and local reentry to occur. 相似文献
867.
Linguistic predictors of adaptive bereavement 总被引:1,自引:0,他引:1
868.
869.
EW Carney AM Hoberman DR Farmer RW Kapp AI Nikiforov M Bernstein ME Hurtt WJ Breslin SZ Cagen GP Daston 《Canadian Metallurgical Quarterly》1997,11(6):879-892
Recent concerns about the potential of certain chemicals to modulate estrogen-regulated processes have led to questions as to how chemicals should be tested for such effects. Therefore, AIHC has developed a comprehensive, resource-efficient, and flexible tiered strategy for estrogen modulation (EM) testing. Levels of evaluation include Tier 0, in which exposure, along with alerts based on structure-activity, persistence, bioaccumulation, and other data, are assessed to prioritize chemicals for preliminary testing. In Tier I, short term in vitro, ex vivo, and/or in vivo assays are used to obtain a preliminary indication of EM potential. Among these, an in vivo response assay is considered the most reliable at this time. However, none of these tests are intended for risk assessment, but rather to aid in choosing chemicals for further testing and in guiding the extent of that testing. Tier II is aimed at risk assessment and involves whole animal tests that contain EM-sensitive end points (e.g., two-generation reproduction study). Tier III consists of hypothesis-driven research reserved for situations where targeted research can reduce levels of uncertainty. This tiered approach provides a framework for the strategic and effective application of EM test methods to address specific information needs on a case by case basis. 相似文献
870.
ME Falagas AM Walker H Jick R Ruthazer J Griffith DR Snydman 《Canadian Metallurgical Quarterly》1998,26(2):384-388
OBJECTIVE: To address clinical features of subacute postictal aggression, we examined aggressive behavior beginning hours to days after the acute confusional postictal period. METHODS: Six patients from our database of 1300 were assessed. Data was obtained from the patients, their family and caretakers, and medical records. One patient was studied with closed circuit video/EEG. RESULTS: There is clinical heterogeneity among these individuals with respect to etiology of epilepsy, age of onset, laterality, memory of adverse behaviors, and presence of psychosis. Several clinical features, including male gender, were common to all. The episodes of postictal aggression were not isolated events, but recurred repeatedly; the behaviors were uniquely stereotyped in each patient. Subacute postictal aggression was more likely after a cluster of seizures than after a single ictus. All patients had medically intractable epilepsy and were remorseful in the interictal period. CONCLUSIONS: Subacute postictal aggression, a rare phenomenon within the broad spectrum of epilepsy-related behaviors, appears to be a true clinical entity with several consistently observed manifestations. 相似文献