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排序方式: 共有3014条查询结果,搜索用时 15 毫秒
161.
RP Millman CL Rosenberg CC Carlisle NR Kramer DM Kahn AE Bonitati 《Canadian Metallurgical Quarterly》1998,113(4):992-996
Twenty-four patients who failed uvulopalatopharyngoplasty (UPPP) for obstructive sleep apnea (OSA) had an adjustable oral (Herbst) appliance made to treat the persistent apnea. Six patients discontinued the device prior to sleep evaluation. Eighteen patients had polysomnographic evaluations at baseline, post-UPPP, and with the Herbst appliance in place. The apnea-hypopnea index baseline (AHI) and arterial oxygen saturation (SaO2) nadir were 42.3+/-6.1 and 83.6+/-1.8%, respectively. There was no significant change in either parameter with surgery. With the oral appliance, the AHI fell to 15.3+/-4.4 (p < or = 0.01) and the SaO2 nadir increased to 87.9+/-1.2% (p < or = 0.05). Ten of the patients had control of the OSA with the Herbst appliance with a fall in the AHI to < 10. There were, in addition, two partial responders as defined by an AHI of <20 and a >50% fall in AHI compared with baseline and post-UPPP values. All but one of the responders and partial responders had complete resolution of subjective symptoms of daytime sleepiness with the appliance. An adjustable oral appliance appears to be an effective mode of therapy to control OSA after an unsuccessful UPPP. 相似文献
162.
L. Gale S. Harris S. Pattison J. Baker J. Fowler 《Journal of the European Ceramic Society》2021,41(5):3167-3176
SiC/SiC ceramic matrix composites (CMCs) are being developed for use in aero-engines to replace nickel superalloy components. Sub-element testing acts as the key stepping stone in bridging understanding derived from basic coupon testing and more complex component testing. This study presents the development of high temperature C-shape sub-element testing with the use of digital image correlation to study damage progression. The specimen is designed with a bias towards a mixed mode-stress state more similar to what a CMC component may see in service. Both monotonic and fatigue tests were completed on C specimens and compared with predicted behaviour from modelling. Test data from both test types suggested that specimens were failing once they reached a critical radial stress level. However evidence from fractography of specimens showed that in both monotonic and fatigue tests radial cracks (driven by hoop stresses) are initiating prior to circumferential cracks. 相似文献
163.
Jeff Niederdeppe Erika Franklin Fowler Kenneth Goldstein James Pribble 《The Journal of communication》2010,60(2):230-253
Many U.S. adults hold fatalistic beliefs about cancer prevention despite evidence that a large proportion of cancer deaths are preventable. We report findings from two studies that assess the plausibility of the claim that local television (TV) news cultivates fatalistic beliefs about cancer prevention. Study 1 features a content analysis of an October 2002 national sample of local TV and newspaper coverage about cancer. Study 2 describes an analysis of the 2005 Annenberg National Health Communication Survey (ANHCS). Overall, findings are consistent with the claim that local TV news coverage may promote fatalistic beliefs about cancer prevention. We conclude with a discussion of study implications for cultivation theory and the knowledge gap hypothesis and suggest foci for future research. 相似文献
164.
W.CL 《军民两用技术与产品》2005,(2):21
全球领先的特种玻管制造商——德国肖特集团新近开发出两种新型玻璃.用于满足纯平液晶电视显示器(LCD—TFT)的市场需求。这两种新型玻璃8688(Tungsten型)和8271(KOVAR型)是专为纯平液晶电视显示器而开发的。 相似文献
165.
The aim of this study was to determine the effect of sitting and standing postures on the repeatability of a stadiometer designed to detect small variations in spinal length. Two groups of ten healthy subjects, with no previous or known history of back problems, participated in this study. One group was measured in the standing posture, while the other group was measured in a sitting posture. All subjects gave informed consent to participate in this study. Subjects had a set of landmarks defining the spinal contour marked on their backs and then stood in the stadiometer for three series of ten measurements to be performed. At the end of each measurement, the subjects were requested to move away from and then be repositioned in the stadiometer. Subjects improved the repeatability across the measurement series. At the end of the second measurement series, all subjects presented mean standard deviations of 0.43 +/- 0.08 mm (range 0.30-0.50 mm) in the standing posture. In the sitting posture, deviations of less than 0.05 mm were obtained only at the end of the third measurement series (0.48 +/- 0.08 mm; range 0.34-0.62 mm), suggesting that this posture required three measurement series before repeatable measurements could be assured rather than two in the standing posture. 相似文献
166.
JS Weissman JS Haas FJ Fowler C Gatsonis MP Massagli GR Seage P Cleary 《Canadian Metallurgical Quarterly》1999,19(1):16-26
In 1982, the World Health Organization (WHO) identified inadequate relief from cancer pain as an international health problem. WHO recommended that governments develop and implement national policies and programs for cancer pain relief. This report evaluates national health policy and the systems of health care delivery in relation to cancer pain management in the new South Africa. This field study included multiple methods of data collection: analysis of documents, field trips with participant observation in sites of care delivery, focused interviews, and in-depth interviews of key informants. The purposive sample of key informants (n = 33) represented multiple stakeholders in a variety of settings. Strengths of the developing health policy include specific recommendations related to palliative care; the shift to universal primary care; policies to support drug availability; the inclusion of morphine and codeine as essential drug at the primary health care level; and the development of a national standard related to cancer pain management. Health services are characterized by two parallel systems of care (private and public) with numerous vestiges of the inequities of apartheid. The management of pain varies by provider and setting; major problems with access exist in the rural areas. Health services in South Africa have been plagued by inequity and inadequate resources. New health policies have set a path to ensure universal access to health care including palliative care for cancer. Their successful implementation is the next necessary step toward improving health services and alleviating the suffering of increasing numbers of individuals with cancer. 相似文献
167.
Most of our present knowledge about the impacts of solar UVB radiation on terrestrial ecosystems comes from studies with plants. Recently, the effects of UVB on the growth and survival of consumer species have begun to receive attention, but very little is known about UVB impacts on animal behavior. Here we report that manipulations of the flux of solar UVB received by field-grown soybean crops had large and consistent effects on the density of the thrips (Caliothrips phaseoli, Thysanoptera: Thripidae) populations that invaded the canopies, as well as on the amount of leaf damage caused by the insects. Solar UVB strongly reduced thrips herbivory. Thrips not only preferred leaves from plants that were not exposed to solar UVB over leaves from UVB-exposed plants in laboratory and field choice experiments, but they also appeared to directly sense and avoid exposure to solar UVB. Additional choice experiments showed that soybean leaf consumption by the late-season soybean worm Anticarsia gemmatalis (Lepidoptera: Noctuidae) was much less intense in leaves with even slight symptoms of an early thrips attack than in undamaged leaves. These experiments suggest that phytophagous insects can present direct and indirect behavioral responses to solar UVB. The indirect responses are mediated by changes in the plant host that are induced by UVB and, possibly, by other insects whose behavior is affected by UVB. 相似文献
168.
JM Larner H Lee RD Little PA Dijkwel CL Schildkraut JL Hamlin 《Canadian Metallurgical Quarterly》1999,27(3):803-809
An asynchronous culture of mammalian cells responds acutely to ionizing radiation by inhibiting the overall rate of DNA replication by approximately 50% for a period of several hours, presumably to allow time to repair DNA damage. At low and moderate doses, this S phase damage-sensing (SDS) pathway appears to function primarily at the level of individual origins of replication, with only a modest inhibition of chain elongation per se. We have shown previously that the majority of the inhibition observed in an asynchronous culture can be accounted for by late G1cells that were within 2-3 h of entering the S period at the time of irradiation and which then fail to do so. A much smaller effect was observed on the overall rate of replication in cells that had already entered the S phase. This raised the question whether origins of replication that are activated within S phase per se are inhibited in response to ionizing radiation. Here we have used a two-dimensional gel replicon mapping strategy to show that cells with an intact SDS pathway completely down-regulate initiation in both early- and late-firing rDNA origins in human cells. We also show that initiation in mid- or late-firing rDNA origins is not inhibited in cells from patients with ataxia telangiectasia, confirming the suggestion that these individuals lack the SDS pathway. 相似文献
169.
PURPOSE: We determine the presence of an open bladder neck during video urodynamic studies and relate that finding to the presence of stress urinary incontinence. MATERIALS AND METHODS: Patients presenting with urinary incontinence, voiding dysfunction or pelvic floor prolapse underwent video urodynamics. With the patient upright and after 200 ml. contrast material had been instilled into the bladder the bladder neck was viewed to determine if it was open or closed. At that point the abdominal leak point pressure was measured. RESULTS: Of 102 women, average age 56.5 years (range 31 to 82), 13% had an open bladder neck and demonstrable stress incontinence on video urodynamics with an average abdominal leak point pressure of 45 cm. water (range 26 to 90). Of those with stress incontinence on urodynamics 23% had an open bladder neck. No continent patient had an open bladder neck. CONCLUSIONS: The presence of an open bladder neck with the bladder filled to 200 ml. correlates strongly with the presence of stress incontinence. 相似文献
170.
These studies were designed to determine the effect of acute alcohol treatment on gestational length and to probe for a mechanism underlying alcohol-induced early onset of parturition (EOP) in mice. Experiment 1: alcohol increases the incidence of EOP. Pregnant C57BL/6J mice were given alcohol (0, 4, 5 or 6 g kg(-1), i.g.) on Gestational Day (GD) 10, 15, 16, 17 or 18. Deliveries were monitored every 6 h from GD 18. Results indicated that 6 g kg(-1) alcohol treatment on GD 17 or 18 increased the incidence of EOP. Experiment 2: prostaglandins (PGs) play roles in parturition. The purpose of Experiment 2 was to determine whether PGs mediate alcohol-induced EOP in mice. The results indicated that pretreatment on GD 17 with aspirin, a prostaglandin synthesis inhibitor, prevented alcohol-induced EOP. These data suggest that alcohol-induced EOP in mice may be mediated by PGs. Experiment 3: PGs are influenced by alcohol and are triggers of labour. Experiment 3 measured uterine PGs associated with the onset of alcohol-induced EOP in mice. Alcohol increased uterine PGE and PGF2alpha, with PGE levels higher than control before labour, and elevated PGF2alpha levels correlating with labour. Changes in gestational length have important implications for pregnancy outcome, as well as for normal fetal growth and development. 相似文献