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71.
Adult male White Leghorn chickens were used in an experimental model system to study atherogenesis, and the effects of an atherogenic diet on plasma lipoprotein composition including carotenoids were determined. This model also included treatment with diazepam, a drug known to reduce formation of atherogenic plaques. After 6 wk consumption of a high-cholesterol, high-triglyceride diet, chickens had mean total plasma cholesterol, triglyceride, and carotenoid concentrations that were significantly increased over those from chicks that consumed the standard diet. Diazepam treatment had no significant effect on whole plasma concentrations of these lipids. Total body weight gain was unaffected by diet, but liver weight expressed as percentage of body weight was significantly increased in chickens that consumed the atherogenic diet. High density lipoprotein (HDL) and low density lipoprotein (LDL) fractions were isolated from plasma samples by ultracentrifugation. The atherogenic diet increased the carotenoid, cholesterol, and protein content of the LDL fractions but not the HDL fractions. 相似文献
72.
Abstract. Regional scientists have had a long fascination with spatial economic interdependence, initially stimulated by the development of a suite of models in Isard (1960). In recent years there have been two major developments; first, a movement towards greater integration in model development not only with large-scale models, but also with careful attempts to make more components of the system endogenous. The second development has been the pursuit of greater integration than in earlier studies between theory and applied regional economic modelling, most notably in the area of trade and economic development. We explore some of the recent developments of this latter approach and provide an assessment of the current state-of-the art of some future opportunities. 相似文献
73.
Huei Wang Kwo Wei Chang Tran L.T. Cowles J.C. Block T.R. Lin E.W. Dow G.S. Oki A.K. Streit D.C. Allen B.R. 《Solid-State Circuits, IEEE Journal of》1996,31(10):1419-1425
A family of millimeter-wave sources based on InP heterojunction bipolar transistor (HBT) monolithic microwave/millimeter-wave integrated circuit (MMIC) technology has been developed. These sources include 40-GHz, 46-GHz, 62-GHz MMIC fundamental mode oscillators, and a 95-GHz frequency source module using a 23.8-GHz InP HBT MMIC dielectric resonator oscillator (DRO) in conjunction with a GaAs-based high electron mobility transistor (HEMT) MMIC frequency quadrupler and W-band output amplifiers. Good phase noise performance was achieved due to the low 1/f noise of the InP-based HBT devices. To our knowledge, this is the first demonstration of millimeter-wave sources using InP-based HBT MMIC's 相似文献
74.
75.
Allen John J.; Chapman Loren J.; Chapman Jean P.; Vuchetich John P.; Frost Laurie A. 《Canadian Metallurgical Quarterly》1987,96(2):83
Correlates of psychotic and psychoticlike symptoms were examined in 60 college students who scored deviantly high on the Perceptual Aberration Scale. High scorers on this scale who also scored high on both the Impulsive Nonconformity Scale and the Depression subscale of the General Behavior Inventory (GBI) showed the most deviant psychotic and psychoticlike symptoms. Moreover, performance on a task of referential communication, the Password Task, was significantly related to such symptoms. The Perceptual Aberration Scale, the Impulsive Nonconformity Scale, and the GBI Depression subscale are recommended for concurrent use in mass screening to select individuals likely to exhibit psychotic or psychoticlike symptoms. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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77.
This paper presents a methodology for specifying the winter and summer peak-load limits for substation transformers that carry a temperature-sensitive load, taking into account the random nature of load and ambient temperature as well as their correlation. With this methodology, we can easily and accurately specify the peak-load limits for each substation transformer once the historical ambient temperature and load data are available. Also, we can collectively specify the peak-load limits for the transformer of each cooling type (OA, OA/FA, or OA/FA/FA) in a geographic region based on the mean and standard deviation of ambient temperatures in that region. Such peak-load limits are useful for power system planning. 相似文献
78.
R Steinmetz NA Mitchner A Grant DL Allen RM Bigsby N Ben-Jonathan 《Canadian Metallurgical Quarterly》1998,139(6):2741-2747
The xenoestrogen bisphenol A (BPA) has been shown to mimic estrogen both in vivo and in vitro. BPA stimulates PRL secretion and the expression of a PRL regulating factor from the posterior pituitary in the estrogen-sensitive Fischer 344 rat (F344), but not in Sprague-Dawley (SD) rats. The goal of the present studies was to examine the in vivo actions of BPA on the reproductive tract. The specific objectives were 1) to characterize the short term effects of BPA on cell proliferation and c-fos expression in the uterus and vagina, and 2) to compare the effects of prolonged exposure to low doses of BPA on the reproductive tract of F344 and SD rats. Treatment with single high doses of BPA induced cell proliferation in the uterus and vagina of ovariectomized F344 rats, as determined by bromodeoxyuridine immunostaining. This proliferation was dose dependent (from 37.5-150 mg/kg) and followed a time course similar to that of estradiol (E2). Quantitative RT-PCR revealed that both BPA and E2 increased c-fos messenger RNA levels in the uterus 14- to 16-fold within 2 h, which returned to basal levels after 6 h. In the vagina, BPA-induced c-fos expression remained elevated for up to 6 h, compared with the transient increase caused by E2. Treatment of F344 rats for 3 days with continuous release capsules that supplied a much lower dose of BPA (approximately 0.3 mg/kg x day) resulted in hypertrophy, hyperplasia, and mucus secretion in the uterus and hyperplasia and cornification of the vaginal epithelium. The reproductive tract of SD rats did not respond to this treatment paradigm with BPA. These studies demonstrate that 1) the molecular and morphological alterations induced by BPA in the uterus and vagina are nearly identical to those induced by estradiol; 2) the vagina appears to be especially sensitive to the estrogenic actions of BPA; 3) the reproductive tract of the inbred F344 rat appears more sensitive to BPA than that of the outbred SD rat; and 4) continuous exposure to microgram levels of BPA is sufficient for exerting estrogenic actions. 相似文献
79.
G Rocco VF Trastek C Deschamps MS Allen DL Miller PC Pairolero 《Canadian Metallurgical Quarterly》1998,66(3):894-6; discussion 897
BACKGROUND: This study examined the results of surgical treatment of leiomyosarcoma of the esophagus. METHODS: Between January 1920 and December 1996, 17 patients (9 men and 8 women) with leiomyosarcoma of the esophagus were treated surgically at the Mayo Clinic. Median age was 58 years and ranged from 26 to 76 years. Symptoms included dysphagia in 11 patients (64.7%) and odynophagia in 6 (35.3%). The tumor was located in the middle third of the esophagus in 10 patients (58.8%) and in the cervical esophagus in 7 (41.2%). Procedures performed included esophagogastrectomy in 9 patients (Ivor Lewis in 5, left thoracoabdominal in 3, and transhiatal in 1), enucleation in 3, transgastric excision in 1, and exploration without resection in 4. RESULTS: The procedure was considered curative in 11 patients (64.7%). There was one operative death (mortality, 5.9%). Complications occurred in 3 patients (17.6%) and included anastomotic leak in 2 and bleeding requiring reoperation in 1. Growth pattern was infiltrating in 7, polypoid in 5, and intramural in 5. Histologically, the tumor was grade 1 in 6 patients, grade 2 in 2, grade 3 in 7, and grade 4 in 2. The tumor was postsurgically classified as stage I in 2 patients, stage IIA in 7, stage IIB in 1, stage IIIA in 5, stage IV in 1, and unknown in 1. Six patients (35.3%) received adjuvant treatment. Follow-up was complete in 16 patients (94.1%) and ranged from 1 to 182 months (median, 48 months). Five- and 10-year actuarial survivals were 47.0% and 31.0%, respectively. Seven patients (41.2%) are currently alive (median survival, 72 months); all underwent curative resection. Factors affecting survival included completeness of resection, growth pattern, postsurgical stage, tumor grade, and tumor location (p < 0.05). CONCLUSIONS: We conclude that leiomyosarcoma of the esophagus is rare. Complete resection provides long-term survival. 相似文献
80.
J Sayos C Wu M Morra N Wang X Zhang D Allen S van Schaik L Notarangelo R Geha MG Roncarolo H Oettgen JE De Vries G Aversa C Terhorst 《Canadian Metallurgical Quarterly》1998,395(6701):462-469
In addition to triggering the activation of B- or T-cell antigen receptors, the binding of a ligand to its receptor at the cell surface can sometimes determine the physiological outcome of interactions between antigen-presenting cells, T and B lymphocytes. The protein SLAM (also known as CDw150), which is present on the surface of B and T cells, forms such a receptor-ligand pair as it is a self-ligand. We now show that a T-cell-specific, SLAM-associated protein (SAP), which contains an SH2 domain and a short tall, acts as an inhibitor by blocking recruitment of the SH2-domain-containing signal-transduction molecule SHP-2 to a docking site in the SLAM cytoplasmic region. The gene encoding SAP maps to the same area of the X chromosome as the locus for X-linked lymphoproliferative disease (XLP) and we found mutations in the SAP gene in three XLP patients. Absence of the inhibitor SAP in XLP patients affects T/B-cell interactions induced by SLAM, leading to an inability to control B-cell proliferation caused by Epstein-Barr virus infections. 相似文献