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排序方式: 共有8368条查询结果,搜索用时 15 毫秒
21.
Yuan Xue Tracy L. Williams Ting Li Joshua Umbehr Liang Fang Weiqun Wang Richard C. Baybutt 《Toxicology in vitro》2005,19(8):1061-1069
This study was to evaluate the effects of cigarette smoke constituents upon type II pneumocyte surfactant production in vitro, and how vitamins A and E may alter the response. Freshly isolated type II pneumocytes from Sprague–Dawley rats were incubated 20 h in medium with fetal bovine serum that was or was not treated with cigarette smoke. The number of adherent cells was inversely related to the dose of smoke or benzo(a)pyrene. Despite the decreased number of treated cells, the total amount of surfactant per culture well was unchanged, whereas surfactant production per cell was significantly increased (P < 0.05). Vitamin A concentration was significantly (P < 0.05) lower in the smoke-treated serum compared with untreated serum. When vitamin A or E was added to the cigarette smoke-treated serum, cell adherence and surfactant production returned to control values. In conclusion, cigarette smoke constituents or benzo(a)pyrene alone decreased the number of adherent type II pneumocytes, but did not alter surfactant amounts because of an increased production of surfactant per cell. Type II pneumocytes seem to adjust surfactant production dependent upon the number of type II pneumocytes to produce it and vitamin A or E enhance cell attachment in the presence of the smoke toxins. 相似文献
22.
Matthew Hoare Tracy Woodall Graeme J M Alexander 《Journal of interferon & cytokine research》2005,25(3):174-176
First-line therapy for hepatitis C virus (HCV) infection comprises interferon-alpha (IFN-alpha) and ribavirin for 6 or 12 months. Mild complications of therapy are common, but more serious complications are rare. Three patients with chronic HCV infection, acquired through injecting drug use, developed idiopathic facial paralysis (Bell's palsy) during therapy, with spontaneous resolution after withdrawal of treatment. Large-scale cohort studies reveal that IFNs are associated rarely with neurologic complications, and only one previous report has linked IFN-alpha therapy and Bell's palsy. We postulate that IFN-alpha therapy led to a breakdown of peripheral tolerance to myelin sheath antigens, leading to neuropathy, just as IFN-alpha therapy can cause autoimmune thyroiditis through breakdown of tolerance to native thyroid antigens. 相似文献
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B A Michna T M Krummel T Tracy J W Brooks A M Salzberg 《The Annals of thoracic surgery》1988,45(5):541-543
Historically, tracheostomy has been used for infants with airway obstruction caused by congenital or acquired subglottic stenosis. Postoperative morbidity and mortality with this provisional operation led Cotton, in 1980, to substitute anterior cricoid split as the primary definitive procedure. Within the past three years, anterior cricoid split has been performed in 4 infants, aged 3 to 9 months, with acquired (3 patients) or congenital (1 patient) subglottic stenosis requiring ventilation through an endotracheal tube. Following cricoid split, the trachea is stented for 12 to 14 days by a nasotracheal tube, with extubation and rigid bronchoscopy in the operating room with the patient under anesthesia to confirm healing and patency. During an 18- to 24-month follow-up in these 4 patients, morbidity has been minimal, patency has persisted, and stridor has not recurred. Accordingly, a conclusive operation, cricoid split, rather than a temporizing tracheostomy may be employed for certain obstructive tracheal lesions early in life. 相似文献
26.
Bradford L. Kirkman-Liff Ruud Lapre Tracy L. Kirkman-Liff 《The International journal of health planning and management》1988,3(2):89-109
The United States and the Netherlands are the focus for this comparative analysis of the evolutionary interaction between health planning and the political system, seen in the context of change in social and economic ideologies. While health planning in the USA started in 1946, it was the comprehensive health planning program in 1966 that created the form to be followed by Health Systems Agency effort in 1974: local, voluntary planning, coordinated by state agencies, supported by federal funding. Health planning in the Netherlands has moved through four distinct periods: a hospital construction period, starting during the post-war recovery; a hospital regionalization period, from 1971 through the late 1970s; a transition period from the late 1970s to 1982, during which several planning approaches were considered; and, the current comprehensive health and social services planning period. Today, federal support for health planning in the US has been eliminated as part of the current de-regulatory, competitive health care strategy. Health planning in the US is now an institutional activity, with less focus on community needs. Advocated changes in the Dutch planning approach incorporate ideas similar to past approaches in the US; but, a failed approach in one nation may work in another, if the underlying cultural and organizational characteristics are sufficiently different. 相似文献
27.
Tracy L. Veach Richard H. Rahe Robbyn L. Tolles Lynn M. Newhall 《Stress and health》2003,19(5):257-264
This study investigates the efficacy of an intensive, integrated approach to stress reduction and coping enhancement directed towards an educated, upper level management population. Ninety‐five US governmental senior managers participated in a 35‐h stress management retreat held over a 3.5‐day period. The retreat combined didactic and experiential activities that were designed to increase participants' knowledge of stress liabilities and coping skills. Participants were encouraged to make positive lifestyle changes and to create specific action plans for the year following the workshop. Evaluations of participant satisfaction were completed at the close of the workshop. Eighty‐three participants completed baseline and follow‐up Stress and Coping Inventory (SCI) assessments in order to identify durable changes in these measures. Across 10 months, participants showed significant improvements in their overall Global Balance scores, psychological symptoms, depression symptoms, and all major coping scales, including Health Habits, Social Support, Responses to Stress and Life Satisfactions. Therefore, an intensive, multifaceted approach to stress intervention is a viable option for encouraging sustained behavioural change. Copyright © 2003 John Wiley & Sons, Ltd. 相似文献
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Adult outcomes of attention deficit hyperactivity disorder and conduct disorder: are the risks independent or additive? 总被引:1,自引:0,他引:1
Tracy D Gunter Stephan Arndt Kristin Riggins-Caspers Gloria Wenman Remi J Cadoret 《Annals of clinical psychiatry》2006,18(4):233-237
METHODS: Data were obtained from a longitudinal study sample of 754 adoptees and categorized based on review of the available adoption agency, medical, and psychiatric records of the biological parents. Categorical data were analyzed using chi2 or Fisher's exact tests, as appropriate. Logistic regression analyses were used to assess the relative contribution of variables. RESULTS: There was not a statistically significant difference in the frequency or type of self-reported adult disruptive behavior, arrests, jail stays, felony arrests, or frequency of conduct disorder (CD) when inattentiveness, impulsivity, and hyperactivity were analyzed individually. The contributions of attention deficit hyperactivity disorder (ADHD) were independent and no additional increased risk for future illegal behavior was conferred by the combination of the disorders. While the effect of CD on illegal behavior was correlated with substance abuse and dependence, ADHD continued to be a significant contributor after controlling for substance abuse and dependence. CONCLUSIONS: Data indicated that ADHD and CD are related but different disorders conferring risk for adult illegal behavior or arrest. In this sample, inattention was the most common domain impaired among those with ADHD, followed closely by hyperactivity, with impulsivity reported least often among those endorsing symptoms of ADHD. 相似文献
30.
R E Tracy 《American journal of kidney diseases》1992,20(2):124-131
The term nephrosclerosis is customarily used to designate a pathological entity that tends to characterize subjects with high blood pressure; it refers to a condition of diffuse fibrous replacement of renal substance secondary to ischemia from hypertension-related vascular injury. The features of parenchymal fibrosis can be distinguished from those of vasculopathies in tissue sections, parenchymal fibrosis being measured by assessing the degree of interstitial fibrosis and by counting obsolete glomeruli, while vasculopathies are measured by determining arterial intimal fibroplasia and by counting hyalinized arterioles. A series of 166 autopsies in subjects aged 25 to 92 years, selected because ample documentation of blood pressure was available, was assessed. One form of vasculopathy, arterial fibroplasia, is a better correlate of high blood pressure than is parenchymal fibrosis in this body of data. Cases with much vasculopathy and little parenchymal fibrosis occurred frequently, and these subjects were usually hypertensive. Cases with little vasculopathy and much parenchymal fibrosis were also encountered, but these subjects were usually not hypertensive. The suggested conclusion is that blood pressure relates less to the renoprival state of nephron loss than it does to renal ischemia in patients with nephrosclerosis. 相似文献