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21.
Reversal of opioid effects by naloxone (NX) can lead to significant cardiovascular problems. We have reported previously that hypercapnic dogs develop greater increases in blood pressure and plasma catecholamine (CA) levels than hypocapnic ones when reversed with naloxone. We have also demonstrated differences between NX and nalbuphine (NBPH) in producing excitatory adrenergic responses when administered during normocapnia. The present study was designed to investigate possible dissimilarities in cardiovascular and sympathetic events after administration of either NX or NBPH in dogs made hypercapnic following fentanyl administration. After induction of anaesthesia with thiopentone and intubation, two groups of dogs were maintained with controlled ventilation on enflurane in oxygen anaesthesia and given 50 micrograms.kg-1 fentanyl IV. This caused a significant decrease in heart rate (HR) (P less than 0.001), mean arterial blood pressure (MAP) (P less than 0.001), and plasma concentrations of norepinephrine (NE) (P less than 0.002). Then, ventilation was decreased to produce a PaCO2 of 60 mmHg; this was accompanied by a significant elevation in plasma level of both epinephrine (EPI) (P less than 0.02) and NE (P less than 0.001). Administration of 20 micrograms.kg-1 NX to six dogs resulted in immediate increases in HR (P less than 0.01) and MAP (P less than 0.01), and a further rise in CA levels to greater than pre-fentanyl baseline values. In six other dogs, NBPH (0.3 mg.kg-1) caused increases in HR (P less than 0.001) and MAP (P less than 0.001) only, and the MAP rise was significantly less than that seen in the NX group (P less than 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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Avian influenza (AI) and Newcastle disease (ND) viruses are heat labile viruses, but exact parameters for heat inactivation at egg pasteurization temperatures have not been established. In this study we artificially infected four egg products with two AI (one low [LP] and one high pathogenicity [HP]) and three ND (two low and one highly virulent) viruses, and determined inactivation curves at 55, 57, 59, 61 and 63 degrees C. Based on D(t) values, the time to inactivation of the viruses was dependent on virus strain and egg product, and was directly related to virus titre, but inversely related to temperature. For all temperatures, the five viruses had the most rapid and complete inactivation in 10% salt yolk, while the most resistant to inactivation was HPAI virus in dried egg white. This study demonstrated that the LPAI and all ND viruses were inactivated in all egg products when treated using industry standard pasteurization protocols. By contrast, the HPAI virus was inactivated in liquid egg products but not in dried egg whites when using the low-temperature industry pasteurization protocol.  相似文献   
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Abstract Rural community and public health nursing are characterized by an impressive commitment of nurses to their communities and a connectedness of people to one another. Home care as an integral part of long-term and acute care for the older adult population has emerged as a vital practice area in community health nursing. The purpose of this ethnographic field study was to describe rural home care for frail older adults from the perspective of those providing and receiving care. More than 250 interviews were conducted with home care providers, recipients and their families, and other community members. The setting included eight culturally and geographically diverse counties in rural Colorado. One major theme is presented: the perceived change in the spirit of rural community nursing due to the overwhelming documentation required for home care reimbursement. Oppressive paperwork requirements impeded practice and resulted in fewer home visits per day, low job satisfaction, increased nursing staff turnover, decreased quality of care, and changed the spirit of community nursing from an emphasis on caring and community service to a focus on reimbursement. The study results have timely implications for health policy formulation as the United States undergoes major health care reform.  相似文献   
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This article examines how the death of a parent, particularly the father, can create an immediate crisis for the surviving spouse and children. The problems of being a widow or being a child or teenager who has lost his or her father to death are explored in detail. Interventions are suggested and explored in terms of the literature, empirical work, and anecdotal material. The authors raise many questions about how death impacts family members and whether or not interventions are needed.  相似文献   
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Arterial oxygen saturation was measured by pulse oximetry in two groups of paediatric outpatients breathing room air during transport from the operating room to the postanaesthetic recovery room. In Group I (n = 60) readiness for transfer from OR to PARR was decided clinically. In Group II (n = 50) additional criteria of oxygen saturation (SaOe) greater than or equal to 98 per cent with end-tidal gas N2O less than or equal to 10 per cent and CO2 less than or equal to 45 mmHg were met. A higher incidence of desaturation (SaO2 less than or equal to 90 per cent) occurred in Group I (27 per cent) than in Group II (eight per cent) (P less than 0.05). More children under 2 yr desaturated in Group I (50 per cent) than Group II (17 per cent) (P greater than 0.05 less than 0.10). Twenty-two patients in each group had a recent history of upper respiratory tract infections. In these patients, desaturation was more marked in those in Group I (32 per cent) than in Group II (five per cent) (P less than 0.05). Within each group, the incidence of desaturation during transport was similar in patients with or without a recent URI.  相似文献   
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Stephenson  Joan 《JAMA》2003,290(6):740
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The current study presents both longitudinal behavioral data and functional activation data documenting the effects of early focal brain injury on the development of spatial analytic processing in two children, one with prenatal left hemisphere (LH) injury and one with right hemisphere (RH) injury. A substantial body of evidence has shown that adults and children with early, lateralized brain injury show evidence of spatial analytic deficits. LH injury compromises the ability to encode the parts of a spatial pattern, while RH injury impairs pattern integration. The two children described in this report show patterns of deficit consistent with the site of their injury. In the current study, their longitudinal behavioral data spanning the age range from preschool to adolescence are presented in conjunction with data from a functional magnetic resonance imaging (fMRI) study of spatial processing. The activation results provide evidence that alternative profiles of neural organization can arise following early focal brain injury, and document where in the brain spatial functions are carried out when regions that normally mediate them are damaged. In addition, the coupling of the activation with the behavioral data allows us to go beyond the simple mapping of functional sites, to ask questions about how those sites may have come to mediate the spatial functions.  相似文献   
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