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931.
932.
Written guidelines based on current research on infant pain assessment and management were developed by an interdisciplinary team in a neonatal intensive care unit of a regional medical center. Charts for infants who had undergone abdominal surgery were reviewed to compare patient outcomes before and after use of this pain management protocol. With the standardization of pain management strategies, the following improvements were noted: decreased length of time to extubation, decreased length of stay, better fluid management, and reduced side effects of narcotics. Additional benefits included improved pain management documentation, decreased cost, and decreased nursing time. 相似文献
933.
A minor class of metazoan introns has well-conserved splice sites with 5'-AU-AC-3' boundaries, compared to the 5'-GU-AG-3' boundaries and degenerate splice sites of conventional introns. Splicing of the AT-AC intron 2 of a sodium channel (SCN4A) precursor messenger RNA in vitro did not require inhibition of conventional splicing and required adenosine triphosphate, magnesium, and U12 small nuclear RNA (snRNA). When exon 3 was followed by the 5' splice site from the downstream conventional intron, splicing of intron 2 was greatly stimulated. This effect was U1 snRNA-dependent, unlike the basal AT-AC splicing reaction. Therefore, U1-mediated exon definition interactions can coordinate the activities of major and minor spliceosomes. 相似文献
934.
K Badizadegan MM Jonas MJ Ott SP Nelson AR Perez-Atayde 《Canadian Metallurgical Quarterly》1998,28(5):1416-1423
Although the epidemiology, natural history, and pathological aspects of chronic hepatitis C are well-defined in the adult population, little is known about the characteristics of chronic hepatitis C infection in children. Reports on the histological features and progression of hepatitis C in children are scarce, and consist primarily of multicenter studies in Japanese and European children. Given the geographic variations in viral genotype and the association of pathology with genotype, whether the Japanese and European studies can be extended to the North American populations is unclear. We report the histopathology of the liver in 40 children with chronic hepatitis C infection treated in a single North American institution. The children included 19 males and 21 females ranging in age from 2.0 to 18.6 years at the time of liver biopsy (mean +/- SD: 11.4 +/- 4.3 years). Our findings indicate that the characteristic histopathological lesions of chronic hepatitis C infection, including sinusoidal lymphocytosis, steatosis, portal lymphoid aggregates/follicles, and bile duct epithelial damage, occur with approximately the same frequencies in children as have been reported in adults. Necroinflammatory activity was generally mild. Portal fibrosis was present in 78% of the specimens, including fibrous portal expansion (26%), bridging fibrosis (22%), bridging fibrosis with architectural distortion (22%), and cirrhosis (8%). Centrilobular pericellular fibrosis, which has not been previously reported in the context of chronic hepatitis C infection in adults or children, was also a prominent feature in our series, occurring with a similar frequency as steatosis or portal lymphoid aggregates/follicles. Our data suggest that in spite of mild histological necroinflammatory activity in general, the stage of fibrosis in children can be severe in spite of relatively short duration of infection. 相似文献
935.
EL Bove FM Lupinetti AK Pridjian RH Beekman LB Callow AR Snider A Rosenthal 《Canadian Metallurgical Quarterly》1993,105(6):1057-65; discussion 1065-6
Although the early mortality for repair of truncus arteriosus has decreased in the modern era, routine correction in the neonate has not been widely adopted. To assess the results of our protocol of early repair, we reviewed 46 neonates and infants undergoing repair of truncus arteriosus at the University of Michigan Medical Center from January 1986 to January 1992. Their ages ranged from 1 day to 7 months (median 13 days) and weights from 1.8 kg to 5.4 kg (mean 3.1 kg). Repair was performed beyond the first month of life in only 8 patients, because of late referral in 7 and severe noncardiac problems in 1. Associated cardiac anomalies were frequently encountered, the most common being interrupted aortic arch (n = 5), nonconfluent pulmonary arteries (n = 4), hypoplastic pulmonary arteries (n = 4), and major coronary artery anomalies (n = 3). Truncal valve replacement was performed in 5 patients with severe regurgitation, 3 of whom also had truncal valve systolic pressure gradients of 30 mm Hg or more. The truncal valve was replaced with a mechanical prosthesis in 2 patients and with a cryopreserved homograft in 3 patients. Right ventricle-pulmonary artery continuity was established with a homograft in 41 patients (range 8 mm to 15 mm), a valved heterograft conduit in 4 (range 12 mm to 14 mm), and a nonvalved polytetrafluoroethylene tube in the remaining patient (8 mm). There were 5 hospital deaths (11%, 70% confidence limits 7% to 17%). Multivariate and univariate analyses failed to demonstrate a relationship between hospital mortality and age, weight, or associated cardiac anomalies. Only 1 death occurred among 9 patients with interrupted aortic arch or nonconfluent pulmonary arteries. Hospital survivors were followed-up from 3 months to 6.3 years (mean 3 +/- 0.4 years). Late noncardiac deaths occurred in 3 patients, all within 4 months after the operation. Actuarial survival was 81% +/- 6% at 90 days and beyond. Despite the prevalence of major associated conditions, early repair has resulted in excellent survival. We continue to recommend repair promptly after presentation, optimally within the first month of life. 相似文献
936.
MJ Mellies AR DeVault K Kassler-Taub ME McGovern HY Pan 《Canadian Metallurgical Quarterly》1993,101(1):97-110
Epidemiologic evidence linking elevated cholesterol concentrations and coronary heart disease (CHD) through the eighth decade of life provides a rationale for lowering cholesterol concentrations to reduce morbidity and mortality from CHD. Pravastatin, a well tolerated HMG CoA reductase inhibitor with a convenient once-daily dosing regimen, has been shown to effectively lower total and low density lipoprotein (LDL) cholesterol. Individual data from more than 1800 hypercholesterolemic patients enrolled in six double-blind, randomized, multicenter studies were pooled and then analyzed to compare the safety and efficacy of pravastatin in the elderly (i.e., patients at least 65 years old) and the non-elderly. In short-term studies (8-16 weeks), response was dose-related and similar in elderly and non-elderly subjects. Pravastatin 20 or 40 mg daily lowered total cholesterol 19-25%, LDL-cholesterol 25-33%, and triglycerides 14-23%; high density lipoprotein (HDL) cholesterol increased 5-10%. During long-term studies, improvements were sustained for more than 24 months in both the non-elderly and elderly. The incidences of adverse drug events and laboratory abnormalities were similar in the elderly and non-elderly patients in all groups (active treatment control with resin, pravastatin alone, or combination therapy). In short-term studies, treatment was discontinued because of adverse events in < 1% of all patients treated with pravastatin (all doses) or placebo. The frequency and profile of adverse events were similar among patients treated with pravastatin or placebo. In long-term studies, treatment was discontinued in 0.4% of patients in the pravastatin group and in 0.3% of the patients in the bile-acid-binding resin group. If drug therapy is warranted, pravastatin appears to be safe and effective for long-term use in elderly patients with hypercholesterolemia. 相似文献
937.
Small-angle X-ray scattering has been employed to study the stability of GP zones in two Al-Zn alloys during fatigue, in order to provide statistically sound information on this process. In a 5.3 at. pct Zn alloy containing l025 zones per m3 with an average diameter of 18 Å, the normally sluggish coarsening was accelerated by fatigue at room temperature by factors of l06 to l07. No coarsening occurred for larger zones, except near a fatigue crack. Reverted samples aged rapidly during fatigue at room temperature, but in a reverted sample of Al-3.5 at. pct Zn cycled at 77 K no appreciable zone growth occurred. Upon warming this sample to room temperature (without any load) rapid clustering took place. These results imply that a vacancy fraction of 10-5 to l0-6 was produced by the fatigue, and this excess vacancy concentration appears to cause the growth during cycling at room temperature. 相似文献
938.
G Richard AR Wright S Harris SZ Doyle B Korge C Mazzanti T Tanaka W Harth OW McBride JG Compton 《Canadian Metallurgical Quarterly》1994,103(5):665-668
Darier's disease (DD) is an autosomal dominant genodermatosis characterized by epidermal acantholysis and dyskeratosis. We have performed genetic linkage studies in 10 families with DD (34 affected) by analyzing 14 polymorphic microsatellite markers. Our results confirm recent reports mapping the DD gene to chromosome 12q23-q24.1. Haplotype analysis of recombinant chromosomes in our families, along with previously reported data, narrow the location of the DD gene to a 5 cM interval flanked by the loci D12S354 and D12S84/D12S105. This localization allowed exclusion of two known genes, PLA2A and PAH, as candidate loci for DD. Three other gene loci (PPP1C, PMCH, PMCA1), mapping in 12q21-q24, remain potential candidates. 相似文献
939.
Empathy was measured by an interview assessing emotions and cognitions in response to videotaped vignettes of persons in affective events and by empathy self-report questionnaires. As hypothesized, empathy was lower among conduct-disordered (CD) than comparison youth and was related inversely to antisocial and aggressive attitudes for all youth tested. Affectively, CD youth (n?=?30) reported fewer concordant emotional responses to vignette persons than did a comparison peer group (n?=?32). Cognitively, CD youth reported fewer correct identifications of vignette persons' emotions, lower mean levels of cognitive attributions for their own responsive emotions, and lower scores on empathy-related cognitive scales. Significant gender differences occurred, with girls scoring higher than boys on empathy questionnaires. Findings are discussed in terms of previous empathy and aggression research, and directions for future study are suggested. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
940.