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131.
EA Debbia U Campora S Massaro E Boldrini GC Schito 《Canadian Metallurgical Quarterly》1996,8(2):96-101
The impetus for shorter hospital stay of mother and newborn infant after delivery is based on economic constraints and parental preference. Earlier published studies did not demonstrate any increase in morbidity rate with shorter stay, but these studies were limited by methodologic flaws and biases that limited the validity and generalizability of the conclusions. More recent studies showed that readmission rates increased with shorter stay and that the severity of illness of readmitted infants may have increased. In addition, the interpretation of current newborn screening tests may not be applicable when performed prior to early discharge. In light of recent changes in neonatal hospital length of stay, a careful review and update of current guidelines and practices for newborn care are required. 相似文献
132.
Glycogen in the placenta and its appendages is important for fetal well-being. The precise location of the glycogen stores, however, is unknown. This study was initiated to quantitate glycogen levels at well-defined sampling sites in more than 641 samples from 10 uncomplicated pregnancies and to correlate these glycogen levels with clinical and morphological variables. By biochemical assay, glycogen levels were greatest in the midumbilical cord section (29.08 +/- 1.18 mg/g dry wt) and lowest in the amnionic membrane (2.31 +/- 0.08 mg/g dry wt). Within the placental disk, parenchymal glycogen levels were greatest near the cord insertion (9.31 +/- 2.68 mg/g dry wt) and lowest at the periphery (5.71 +/- 1.14 mg/g dry wt). The midumbilical cord glycogen level showed strong direct correlations (P < .001) with birth weight, umbilical cord weight, and total calculated umbilical cord glycogen and somewhat lower but significant (P < .037) direct correlations with the calculated mean umbilical cord glycogen level, total calculated placental glycogen content, and placental weight. The glycogen level in the middisk parenchymal section from the fetal surface correlated directly with gestational age. Periodic acid-Schiff stains showed that magenta glycogen granules were most abundant in the cytoplasm of the vascular smooth muscle cells. These data show significant variations in glycogen levels among sampling sites. Definition of the precise sampling site is important for clinicopathologic studies of placental glycogen and for interstudy correlations. 相似文献
133.
SM Haslam GC Coles EA Munn TS Smith HF Smith HR Morris A Dell 《Canadian Metallurgical Quarterly》1996,271(48):30561-30570
Structural studies on the N-linked oligosaccharides of Haemonchus contortus, an economically important nematode that parasitizes domestic ruminants, have revealed core fucosylation of a type not previously observed in any eukaryotic glycoprotein. Mass spectrometric analyses were performed on detergent extracts of homogenized adult H. contortus and on purified H11, a glycoprotein isolated from intestinal brush borders which has been previously shown to be an effective vaccine antigen. The major N-linked glycans identified in the present study have up to three fucose residues attached to their chitobiose cores. The fucoses are found at the 3- and/or 6-positions of the proximal GlcNAc and at the 3-position of the distal GlcNAc. The latter substitution is unique in N-glycans. Most anti-H11 monoclonal antibodies are known to recognize carbohydrate epitopes, and it is possible that the newly discovered multifucosylated core structures are highly immunogenic in this glycoprotein. 相似文献
134.
EA Dean-Nystrom BT Bosworth HW Moon AD O'Brien 《Canadian Metallurgical Quarterly》1998,66(9):4560-4563
Enterohemorrhagic Escherichia coli (EHEC) strains require intimin to induce attaching and effacing (A/E) lesions in newborn piglets. Infection of newborn calves with intimin-positive or intimin-negative EHEC O157:H7 demonstrated that intimin is needed for colonization, A/E lesions, and disease in cattle. These results suggest that experiments to determine if intimin-based vaccines reduce O157:H7 levels in cattle are warranted. 相似文献
135.
136.
137.
KN Furuya PR Durie EA Roberts SJ Soldin Z Verjee L Yung-Jato E Giesbrecht L Ellis 《Canadian Metallurgical Quarterly》1995,28(5):531-540
N-Acetyl aspartate (NAA) is the second most abundant amino acid in the human brain. NAA is synthesized by L-aspartate N-acetyl transferase or by cleavage from N-acetyl aspartyl glutamate by N-acylated alpha-linked L-amino dipeptidase (NAALADase); and it is catabolized to acetate and aspartate by N-acetyl aspartate amino hydrolase (amino acylase II). NAA is localized primarily to neurons, where it is concentrated in the cytosol. Although NAA is devoid of neurophysiological effects, it serves as an acetyl donor, an initiator of protein synthesis or a carbon transfer source across the mitochondrial membrane. The concentration of NAA in human brain increases 3-fold between midgestation and adulthood. In Canavan's Disease, an autosomal recessive disorder due to a null mutation in amino acylase II, NAA levels in brain are markedly increased and disrupt myelination. NAA levels have been found to be reduced in neurodegenerative disorders, including Alzheimer's Disease and Huntington's Disease. Since endogenous NAA can be readily detected in human brain by magnetic resonance spectroscopy, it is increasingly being exploited as a marker for functional and structural integrity of neurons in an expanding number of disorders. 相似文献
138.
Data from an anonymous survey of 3,690 adolescents were used to assess how much of the unique variance in adolescents' self-reported drug use was accounted for by number of parents in comparison to the adolescents' sex, age, social class, and peer drug use. Multiple regression revealed that the contribution of number of parents was small and nonsignificant compared to peer use, student age, parental occupation and remarriage, student sex, and parental unemployment. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
139.
AV Nedostup EA Bogdanova EI Mikhnovski? AA Platonova 《Canadian Metallurgical Quarterly》1977,17(4):85-90
The structure of cardiac rhythm was studied with the help of specialized computers during digitalization in 60 patients with atrial fibrillation of different etiology. The reduction of the heart contractions rate under digitalization is accompanied by certain changes in the structure of cardiac rhythm: the arrhythmic pattern of the ventricular contractions increases with a predominant growth of the number of long R--R intervals, the transitions from short intervals to longer ones become sharper, and portions of a relatively stable ventricular rhythm appear. Three main types of dynamics of the rhythm structure were distinguished on the basis of the changes in the interval R--R histogram. The described changes in the structure of cardiac rhythm are not specific, but when Digitalis drugs are used alone they can be used as additional criteria for digitalization. 相似文献
140.
Although patients taking phenformin are more likely to develop lactic acidosis in the presence of renal, cardiovascular, or hepatic disease, criteria for safe use of the drug are not well established. Eight diabetics died of lactic acidosis in Nottingham in 1972-5 and all were taking phenformin in therapeutic doses. Six had attended the diabetic clinic within a month of their terminal illness. Two patients had appreciable renal impairment and should not have been given phenformin. Four had hypertension and minimal evidence of renal disease, while in two no predisposing factor was identified. There are so many contraindications to the use of phenformin that it is doubtful whether patients on the drug can be monitored adequately. We suggest that phenformin should be withdrawn from general use. 相似文献