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81.
G Bokinsky M Miller K Ault P Husband J Mitchell 《Canadian Metallurgical Quarterly》1995,108(3):625-630
STUDY OBJECTIVE: To determine whether alterations of platelet reactivity occur during obstructive sleep apnea (OSA) and, if so, whether therapy with nasal-continuous positive airway pressure (N-CPAP) alters this reactivity. DESIGN: Patients with suspected moderate to severe OSA had blood drawn for spontaneous platelet aggregation (sAGG) and activation (sACT) measurements at hourly intervals during diagnostic polysomnography (PSG) and, in those with confirmed OSA, on a separate night during which N-CPAP was applied. SETTING: Tertiary care center sleep laboratory. PATIENTS: Six patients with OSA had matched blood samples drawn on both diagnostic and N-CPAP treatment nights. Five patients without confirmed OSA served as controls. INTERVENTIONS: N-CPAP was applied to those patients with OSA and pressures adjusted with goals of eliminating apneas; N-CPAP was then maintained through the night. MEASUREMENTS AND RESULTS: sACT and sAGG were measured using flow cytometric determination of P-selectin expression using a monoclonal antibody. Platelet aggregation was assessed by measuring the proportion of platelets larger than resting platelets by light scatter techniques. Mean values for sACT and sAGG were higher on the diagnostic night compared with treatment night (p = 0.001 and p = 0.003, analysis of variance, respectively). The mean baseline supine sACT compared with completion supine sACT for both diagnostic and N-CPAP nights also revealed significant differences (mean = 16.6 +/- 3.5% vs 36.9 +/- 7.5%, p = 0.04; and 11.9 +/- 3% vs 39.5 +/- 9.1%, p = 0.04). Platelet activation during sleep in five subjects without OSA resembles that found in patients with OSA during N-CPAP. CONCLUSIONS: Increased platelet sACT and sAGG occur during sleep in patients with OSA. This effect is greatly reduced by N-CPAP. 相似文献
82.
W J Cole P J Eppard B G Boysen K S Madsen R H Sorbet M A Miller R L Hintz T C White W E Ribelin B G Hammond 《Journal of dairy science》1992,75(1):111-123
Eighty-two lactating Holstein cows in their first, second, or third lactation received either one, three, or five concurrent i.m. injections of a unit dose (.6 g) of zinc methionyl bST (sometribove) or five doses of the vehicle. Injections were given at 14-d intervals from 60 +/- 3 d postpartum until the end of lactation or necropsy. Thirty-eight animals were continued on treatment for a 2nd yr. Sometribove did not affect the incidence of ketosis, milk fever, tetany, or pneumonia. Digestive disorders, primarily cows going off feed, were increased by bST during yr 1 only. The incidence of lameness was increased by bST in some time frames because of an increase in the 3.0-g bST group. Lameness was not associated with treatment-specific histopathologic changes or with abnormalities in cartilage or bone. Reproductive health generally was unaffected by treatment, but delayed conception and increased incidence of abortion were noted. Incidence of cystic ovaries was unaffected by bST. Pregnancy rates were decreased during the 100-d breeding interval of yr 1 but not during the 215-d interval of yr 2. The incidence of clinical mastitis was increased by bST, primarily at the 3.0-g dose. During the 2-yr study, 0, 3, 3, and 2 cows died or became moribund on 0, .6, 1.8, and 3.0 g of bST, respectively. Health issues identified for further evaluation included lameness and clinical mastitis for the 3.0-g group and early removal from the herd and decreased reproductive performance for all bST groups. Bovine somatotropin caused no treatment-specific toxic effects in dairy cows even at 3.0 g every 14 d. 相似文献
83.
Demir H.V. Jun-Fei Zheng Sabnis V.A. Fidaner O. Hanberg J. Harris J.S. Jr. Miller D.A.B. 《Semiconductor Manufacturing, IEEE Transactions on》2005,18(1):182-189
This work reports an easy planarization and passivation approach for the integration of III-V semiconductor devices. Vertically etched III-V semiconductor devices typically require sidewall passivation to suppress leakage currents and planarization of the passivation material for metal interconnection and device integration. It is, however, challenging to planarize all devices at once. This technique offers wafer-scale passivation and planarization that is automatically leveled to the device top in the 1-3-/spl mu/m vicinity surrounding each device. In this method, a dielectric hard mask is used to define the device area. An undercut structure is intentionally created below the hard mask, which is retained during the subsequent polymer spinning and anisotropic polymer etch back. The spin-on polymer that fills in the undercut seals the sidewalls for all the devices across the wafer. After the polymer etch back, the dielectric mask is removed leaving the polymer surrounding each device level with its device top to atomic scale flatness. This integration method is robust and is insensitive to spin-on polymer thickness, polymer etch nonuniformity, and device height difference. It prevents the polymer under the hard mask from etch-induced damage and creates a polymer-free device surface for metallization upon removal of the dielectric mask. We applied this integration technique in fabricating an InP-based photonic switch that consists of a mesa photodiode and a quantum-well waveguide modulator using benzocyclobutene (BCB) polymer. We demonstrated functional integrated photonic switches with high process yield of >90%, high breakdown voltage of >25 V, and low ohmic contact resistance of /spl sim/10 /spl Omega/. To the best of our knowledge, such an integration of a surface-normal photodiode and a lumped electroabsorption modulator with the use of BCB is the first to be implemented on a single substrate. 相似文献
84.
85.
Abstract: Researchers frequently approach questions dealing with local fiscal decision‐making using economic models. These models typically base the demand for public services on a set of socioeconomic characteristics that serve as rough proxies for voter preferences. Our study focuses more directly on preference formation and explores the nature of the relationship between citizens’ attitudes about police services and their willingness to pay for them. We pay particular attention to the role of demographic traits, television media, and direct contact with service providers. We present data from a survey of Connecticut adults and use these data to test direct and indirect effects models with regression analysis. We find evidence that attitudes about police predict willingness to pay for police services, holding the demographic attributes of respondents constant. We also find that the effects of some demographic traits on demand for services are mediated by preferences, as are some types of experience and media exposure. 相似文献
86.
Peer-assisted learning interventions with elementary school students: A meta-analytic review. 总被引:1,自引:0,他引:1
Rohrbeck Cynthia A.; Ginsburg-Block Marika D.; Fantuzzo John W.; Miller Traci R. 《Canadian Metallurgical Quarterly》2003,95(2):240
A meta-analytic review of group comparison design studies evaluating peer-assisted learning (PAL) interventions with elementary school students produced positive effect sizes (ESs) indicating increases in achievement (unweighted mean ES = 0.59, SD = 0.90; weighted ES, d = 0.33, p 相似文献
87.
Kaslow Nadine J.; Rubin Nancy J.; Forrest Linda; Elman Nancy S.; Van Horne Barbara A.; Jacobs Sue C.; Huprich Steven K.; Benton Sherry A.; Pantesco Victor F.; Dollinger Stephen J.; Grus Catherine L.; Behnke Stephen H.; Miller David S. Shen; Shealy Craig N.; Mintz Laurie B.; Schwartz-Mette Rebecca; Van Sickle Kristi; Thorn Beverly E. 《Canadian Metallurgical Quarterly》2007,38(5):479
Working collaboratively, psychologist educators and trainers at the doctoral, internship, and postdoctoral levels; credentialers; practitioners; and students offer 8 proposals for psychologists to consider in recognizing, assessing, and intervening with problems of professional competence in students and practicing professionals. In the proposals, the authors address the following topics: definitions and categories; preparing the system; self-assessment; remediation; diversity; communication across various levels of the system; confidentiality; and ethical, regulatory, and legal underpinnings. They also propose future directions for the assessment of problems in professional competence in both students and practicing psychologists. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
88.
Makarand Hastak Amir Mirmiran Richard Miller Ronak Shah Reid Castrodale 《Canadian Metallurgical Quarterly》2003,8(5):267-272
Precast bridges are often constructed as single span for dead load, but continuous for live load. A diaphragm connection is provided for negative moment continuity. However, the connection may also be subjected to positive moments due to time-dependent effects. Because these moments may be large enough to damage the diaphragm or even the girders, a positive moment connection is often provided. This paper reports on a study to determine the types of positive moment connections used across the country and to identify potential problems with these types of connections. A questionnaire survey was conducted to assess the state of practice for precast prestressed concrete bridges made continuous. The survey provides valuable information on this type of bridge and updates a previous survey on this subject. 相似文献
89.
90.
In pre-industrial times, honey was the main source of concentrated sweetness in the diets of many peoples. There are no precise figures for per capita consumption during most periods in history because honey was part of either a hunter-gatherer or subsistence economy. Until now, historians and food writers have proposed that it was a scarce commodity available only to a wealthy few. We do know, however, that in a cash economy honey was sold in large units (gallons and even barrels) and it was present in such abundance that mead, made from honey, was a common alcoholic drink. A reappraisal of the evidence from the Stone Age, Antiquity, the Middle Ages and early Modern times suggests that ordinary people ate much larger quantities of honey than has previously been acknowledged. Intakes at various times during history may well have rivalled our current consumption of refined sugar. There are implications therefore for the role of sugar in modern diets. Refined sugar may not have displaced more nutrient-rich items from our present-day diets but only the nutritionally comparable food, honey. 相似文献