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91.
V Kudryashov G Ragupathi IJ Kim ME Breimer SJ Danishefsky PO Livingston KO Lloyd 《Canadian Metallurgical Quarterly》1998,15(3):243-249
OBJECTIVE: The objective of this study was to assess the degree of BP Tracking from childhood to adulthood and to evaluate whether high BP levels persist over time and progress to adult hypertension. PATIENTS AND METHODS: Two hundred and twenty-two healthy schoolchildren living in the North of Portugal were assessed at 17 year intervals, starting in 1979 (cohort 1) aged 5 to 18 years, and again in 1996 (cohort 2). Tracking indices (Ti) were calculated as follows: Ti = (2x + y-z) /N/0.89, where x, y and z refer to the total number in the same, adjacent and remote trisections, respectively, and N = x + y + z. If Ti > 1 there is positive tracking. RESULTS AND CONCLUSIONS: For systolic and diastolic blood pressure, all Ti were greater than 1.0. All individuals that remained in the 3rd tertil, 17 years later, weigh more and are more obese than those of the 1st tertil. 56.6% of the individuals that belong to the 3rd tertil are now hypertensive, which means that a significant percentage of the children with high blood pressure in the first survey will be hypertensive in the future. 相似文献
92.
A Shuper IJ Cohen C Mor S Ash L Kornreich R Zaizov 《Canadian Metallurgical Quarterly》1998,51(5):1336-1338
OBJECTIVE: To evaluate the incidence and clinical characteristics of CNS involvement in Ewing family of tumors (EF) in children. METHODS: Chart reviews of children with EF treated in our center from 1972 to 1997. Clinical and imaging data regarding possible CNS involvement were collected. RESULTS: During this 25-year period, 80 children with EF were treated. Intracranial involvement was found in eight (10%) children: the brain was involved in seven children (8.8%) and a retro-orbital metastasis without parenchymal brain involvement was noted in one child. Metastases were localized intrahemispherically, or in the cerebellum or the basal ganglia. Intracranial spread was hematogenous in five children and by contiguous spread from the skull in three children. Intracranial involvement was diagnosed 1.3 to 11 years from initial presentation. Seizures and hemiparesis were the main neurologic complications. CONCLUSIONS: The rate of parenchymal brain involvement in our patients with EF was 8.8%. Spread was mainly hematogenous. Substantial morbidity was associated with CNS disease, which appeared in most patients late in the course of disease. 相似文献
93.
ABSTRACT: Frozen rainbow trout fillets were brined in 8.7 or 17.4% sodium chloride solutions for various periods. Brine uptake, brined and cooked pH, cook yield, shear force, total and water-phase salt content, and brined and cooked proximate composition were determined. Fish mince was used for texture (hardness and cohesiveness) and protein solubility (total soluble and myofibrillar proteins) evaluations. Increasing the brine concentration increased fillet weight loss after brining, cook yield, water-phase salt content, shear force, brined fat, brined and cooked ash, brined pH, and brined and cooked moisture. 相似文献
94.
This study was designed to determine the relative activity of basic fibroblast growth factor (bFGF), vascular endothelial growth factor/vascular permeability factor (VEGF/VPF), platelet-derived growth factor (PDGF), platelet-derived endothelial cell growth factor (PD-ECGF), hepatocyte growth factor (HGF), and interleukin-8 (IL-8) in regulating endothelial cell division, migration, degradation of the extracellular matrix (ECM), morphogenesis, and survival. Human umbilical vein endothelial cells (HUVEC) were treated with different concentrations of the six cytokines. bFGF was the most potent mitogen followed by VEGF/VPF and PD-ECGF. VEGF/VPF and bFGF also enhanced the survival of the endothelial cells in serum-free medium. Interstitial collagenase (MMP-1) and urokinase plasminogen activator (uPA) were significantly upregulated only by bFGF. HGF, bFGF, and VEGF/VPF induced chemotactic migration of the endothelial cells, but only HGF (scatter factor) enhanced nondirectional motility. The organization of endothelial cells to form tubes on Matrigel was induced by bFGF and, to a lesser extent, by VEGF/VPF and IL-8. Permeability across endothelial cell monolayers was induced only by VEGF/VPF. These data demonstrate that different angiogenic molecules differentially regulate distinct steps in the process of angiogenesis, suggesting that any given molecule may be necessary but in itself insufficient for establishment of a viable vasculature. 相似文献
95.
Microdialysis and gas chromatography/mass spectrometry was used for the measurement of extracellular N-acetylaspartate (NAA) and N-acetylaspartylglutamate (NAAG) in rat hypothalamus. The sensitivity of the method for each of these compounds was approximately 5 pmol/30 microliters of dialysate. Baseline NAA concentrations in dialysate were estimated to be approximately 25 pmol/36 microliters, while that for NAAG was at or below the detection limit of 5 pmol/ 36 microliters. In vivo and in vitro calibrations of microdialysis probes showed that the recovery for NAA was approximately 10 percent. For NAAG, the in vitro recovery was 6.3%, and in vivo recovery, 11%. Depolarization stimulation using 100 mM KCl in the microdialysis perfusate was employed to measure extracellular NAA and NAAG concentrations. Extracellular NAA was elevated to approximately 70 pmol/36 microliters dialysate following depolarization. No significant elevation of NAAG was observed. By infusing known amounts of stable isotopically labeled NAAG-d3 via the microdialysis probe and measuring the isotopically labeled catabolic product, NAA-d3, in collected microdialysate, we were able to confirm the existence of one or more hydrolytic enzymes active towards NAAG in the hypothalamus. This finding suggest the possible involvement of active metabolic processes in the relationship between NAAG and NAA releases. 相似文献
96.
This paper describes a unifying approach to the computation of certain robustness measures for some calculations involving
state space models in control and system theory. These measures include nearness to uncontrollability, nearness to instability,
and nearness to unstabilizability and their duals. Specialized results are provided for systems in companion form (controllability
canonical form, etc.). It is shown analytically why high-order companion system models have certain undesirable numerical
properties. For example, it is shown that almost all highorder companion matrices are nearly singular and almost all high-order
controllable canonical forms are nearly uncontrollable.
This research was supported by the Office of Naval Research under Contract No. N00014-85-K-0553 and the National Science Foundation
(and AFOSR) under Grant No. ECS-8718897. 相似文献
97.
Kenney Martha D.; Mason William A.; Hill Suzanne D. 《Canadian Metallurgical Quarterly》1979,15(2):176
Studied the development of lipsmacking and grimacing, facial expressions associated with friendliness and fear, respectively, in 26 rhesus monkeys raised under 3 conditions that included visual exposure to (a) monkeys and people, (b) one monkey, (c) neither monkeys nor people. Ss were tested through Life Weeks 1–22 for responses to their mirror image or a human face. Age, stimulus configuration, and experience interacted in the development of the 2 responses. Lipsmacking generally occurred earlier than grimacing and was most frequently elicited by the face. Frequency of lipsmacking increased initially, then declined; in contrast, frequency of grimacing increased progressively throughout testing. Rearing conditions significantly affected age of first response, level of responsiveness, and stimulus differentiation. The most restricted group was oldest at first response, least responsive, and showed the weakest differentiation of stimuli; the most experienced group was at the opposite extreme on these comparisons. (24 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
98.
We have studied the characteristics of the stimulation of adenyl cyclase (AC) activity in human thyroid plasma membranes by thyroid-stimulating hormone (TSH) and by immunoglobulin G (IgG) from the sera of patients with Graves' disease. AC activity was measured as adenosine 3',5'-cyclic monophosphate (cAMP) generated by membranes in a 10 minute incubation. IgG from two patients with Graves' disease possessed particularly potent human thyroid AC-stimulating activity; the dose-response curves with these IgGs were essentially parallel to those obtained with TSH. As little as 30 mug of the IgG of one patient with Graves' disease or 8 muU of TSH caused significant AC stimulation. A Lineweaver-Burk plot of the data suggested similarity in the site of action of both TSH and human thyroid adenyl cyclase stimulator (HTACS) in Graves' IgG. Submaximal doses of HTACS and TSH had additive effects on AC stimulation, but a large dose of a Graves' IgG with potent AC stimulating activity did not enhance AC stimulation by a maximal dose of TSH. The effect of HTACS on AC was slower in onset and longer in duration than an equipotent dose of TSH. HTACS was detectable in IgGs of 9 of 15 untreated hyperthyroid Graves' disease patients; its concentration, however, did not correlate significantly with tests of thyroid function, nor with long-acting thyroid stimulator (LATS) activity. In another 11 treated patients with Graves' disease, selected for the presence of LATS, HTACS and LATS were significantly correlated. We observed no inhibition of LATS activity in a Graves' IgG chosen for such testing because of its high titer of HTACS and no detectable LATS. However, an inhibitor of HTACS was detected in 2 of 4 IgGs; one of these two IgGs also inhibited AC stimulation by TSH. Conclusions: 1) Some Graves' disease IgGs contain a human thyroid AC stimulator (HTACS), probably different from LATS. 2) HTACS may act via a common pathway with TSH; it differs from TSH, however, in having a slower onset and a greater effect during more prolonged incubation with plasma membranes. 3) There is also an inhibitor of HTACS activity in some Graves' disease IgGs. 相似文献
99.
IJ Al-Jumaili 《Canadian Metallurgical Quarterly》1976,236(1):113-119
Proteocine production was found to the influenced by the medium used, the temperature of incubation and the length of incubation. Different amounts of proteocine were produced in different media. Production in liquid media was maximum in proteose-peptone No. 3 (Difco). This medium gave a very high titre (1:10000) of proteocine when inoculated with the producer strain, and the aerated culture was induced with mitomycin C. Therefore a method of producing a high titre proteocine was developed using proteosepeptone No. 3 (Difco) and cultural conditions of 25 degrees C for 24 hours. 相似文献
100.