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81.
Chronic obstructive pulmonary disease is one of the most significant chronic illnesses of adults. Comprehensive care of the affected patient requires the medical-surgical nurse to have knowledge of the disease process, collaborative management, and nursing care based on research and current practice guidelines.  相似文献   
82.
Protein synthesis in skeletal muscle is known to decrease during contractions but the underlying regulatory mechanisms are unknown. Here, the effect of exercise on skeletal muscle eukaryotic elongation factor 2 (eEF2) phosphorylation, a key component in protein translation machinery, was examined. Eight healthy men exercised on a cycle ergometer at a workload eliciting ∼67% peak pulmonary oxygen consumption     with skeletal muscle biopsies taken from the vastus lateralis muscle at rest as well as after 1, 10, 30, 60 and 90 min of exercise. In response to exercise, there was a rapid (i.e. < 1 min) 5- to 7-fold increase in eEF2 phosphorylation at Thr56 that was sustained for 90 min of continuous exercise. The in vitro activity of skeletal muscle eEF2 kinase was not altered by exercise indicating that the increased activity of eEF2 kinase to eEF2 is not mediated by covalent mechanisms. In support of this, the increase in AMPK activity was temporally unrelated to eEF2 phosphorylation. However, skeletal muscle eEF2 kinase was potently activated by Ca2+–calmodulin in vitro , suggesting that the higher eEF2 phosphorylation in working skeletal muscle is mediated by allosteric activation of eEF2 kinase by Ca2+ signalling via calmodulin. Given that eEF2 phosphorylation inhibits eEF2 activity and mRNA translation, these findings suggest that the inhibition of protein synthesis in contracting skeletal muscle is due to the Ca2+-induced stimulation of eEF2 kinase.  相似文献   
83.
Audiogenic seizures can be induced in DBA/2J mice following intense auditory stimulation. A number of neurotransmitters, including 5-hydroxytryptamine (5-HT), are believed to be involved in mediating this effect since it has been shown previously that depletion of 5-HT or blockade of 5-HT receptors protects DBA/2J mice from these audiogenic seizures. The present study was undertaken to determine whether antagonism of the newly identified 5-HT7 receptor may protect DBA/2J mice from audiogenic seizures by attempting to correlate in vivo potency of compounds with their affinity at the 5-HT7 receptor. All compounds used in the correlation were shown to be antagonists at the 5-HT7 receptor and a statistically significant correlation was observed between 5-HT7 affinity and doses for half-maximal response (ED50) for protection of DBA/2J mice from sound-induced seizures (r = 0.80; P < 0.05). No significant correlation was observed between in vivo activity and affinity at either 5-HT1A, 5-HT2A or 5-HT2C receptors. It is also unlikely that interactions between the 5-ht5 receptor will protect DBA/2J mice from audiogenic seizures since metergoline and mesulergine which are both active in this in vivo model have no affinity for the 5-ht5 receptor. There are similarities between the pharmacology of the 5-HT7 receptor and that of the 5-HT1A receptor, however the correlation between the in vivo potency in DBA/2J mice and 5-HT1A affinity was not significant. Furthermore, the 5-HT1A receptor antagonist WAY 100135 did not protect DBA/2J mice from audiogenic seizures at doses that antagonise 5-HT1A receptor-mediated effects in mice. These data suggest that antagonism of 5-HT7 receptors may protect against audiogenic seizures in DBA/2J mice although a definitive conclusion must await studies with selective 5-HT7 antagonists. Received: 20 March 1997 / Accepted: 10 August 1997  相似文献   
84.
Risk Factors for a First Febrile Seizure: A Matched Case-Control Study   总被引:10,自引:6,他引:4  
Summary We conducted a matched casecontrol study to identify risk factors for first febrile seizures, with special emphasis on characteristics of the acute illness episode. Cases were identified through hospital emergency departments; controls were identified through outpatient clinics and emergency departments. Sixtynine children with first febrile seizures and no history of previous unprovoked seizures were matched for age (±6 months), site of routine pediatric care, and date of visit (±weeks) with 1 or 2 febrile controls who had no history of previous febrile or unprovoked seizures. Medical records for the index visit were reviewed, and parents were interviewed by telephone. Illness characteristics examined included height of temperature, type of underlying illness, contact with a physician during the illness but before the index visit, and use of acetaminophen or decongestants. Family history of febrile and of unprovoked seizures, sociodemographic characteristics, daycare use, and selected preand perinatal variables were also studied. On multivariable analysis, significant independent risk factors were height of temperature, history of febrile seizures in a firstor in a higher degree relative. Gastroenteritis as the underlying illness had a significant inverse (i.e., protective) association with febrile seizures. Maternal smoking during pregnancy was a marginally significant predictor of febrile seizures.  相似文献   
85.
Anthropology, and its supposed operationalisation within transcultural nursing, is becoming increasingly prominent in educational curricula in the U.K. This increase in interest is driven both by governmental pressure to provide more culturally appropriate care, and an intuitive notion that anthropology, nursing and other related professions such as midwifery have a common basis of mutually overlapping and re-enforcing theory and practice. This paper explores the question of whether there is a natural alliance between anthropology, and the applied aspects of health care disciplines such as nursing and midwifery, by examining some of the concepts underlying each discipline, and the ways in which these concepts are applied in practice. Anthropology is the study of culture, and it is suggested that a more complete understanding of this central concept is essential if it is to be utilised in the applied disciplines encompassed by the practice of nursing and midwifery.  相似文献   
86.
This paper examines the equality of utilization for equal need and equity of out-of-pocket expenditure for health services in a large urban area in Thailand. Data from a household health interview survey were used to explore patterns of perceived morbidity, utilization of various treatment sources, and out-of-pocket payment. Financial access to health care, as reflected in medical benefit/insurance cover, appeared to influence reported illness and hospitalization rates. Gross lack of access to health care amongst lower socio-economic groups was not the main problem in this densely populated urban area because people could choose and use alternative health services according to their ability and willingness to pay. The corollary, however, was an inequitable pattern of out-of-pocket health expenditure by income quintile and per capita. The underprivileged were more likely to pay out of their own pocket for their health problems, and to pay out of proportion to their household income when compared with more privileged groups. Furthermore, the underprivileged were least likely to be covered by government health benefit schemes, in contrast in particular to civil servants, who paid less out of pocket and did not contribute to their medical benefit fund. The private health sector (private clinics and private hospitals) was the major provider of health care to urban dwellers for both outpatient and inpatient services. Policy options for the short and long term to improve the equity of payment systems for health care are discussed.  相似文献   
87.
The crystallization behavior of coextruded microlayered sheets comprised of 657 alternating layers of polycarbonate (PC) and a miscible copolyester of mainly 1,4-cyclohexanedimethanol and terephthalic acid (KODAR) was investigated as a function of annealing time when the KODAR was crystallized isothermally from the glass at 195°C. Comparisons were made with crystallization of KODAR alone, and with crystallization of KODAR from melt blends with PC. The kinetics of crystallization and the morphology of the crystallized KODAR were characterized with differential scanning calorimetry, and by examination of thin sections microtomed from annealed specimens in the polarized light microscope and the transmission electron microscope. The growth rate of small, birefringent KODAR spherulites was non-linear, and was strongly affected by diffusion of PC into the KODAR layers. Diffusion of amorphous PC into the KODAR layers retarded nucleation and spherulite growth and decreased spherulite density. The effect became more pronounced as the KODAR layer thickness was reduced. Spherulities nucleated randomly throughout the KODAR layers in the PC/KODAR 20/80 (w/w) microlayer and grew rapidly to form a continuous layer of impinged spherulites. In contrast, spherulites in the PC/KODAR 40/60 and 60/40 microlayers nucleated and grew along the center of the KODAR layers where the KODAR concentration was highest.  相似文献   
88.
Impalement injuries to the upper extremity are rare. A case is described of penetration of a 10 x 3.5-inch fence post into the left shoulder of a 16-year-old boy, pinning the shoulder to the chest wall. Sequelae of potential serious brachioplexus, vascular, and intrathoracic injuries are reviewed. The author presents a systematic treatment approach to the assessment, extrication, and microneurovascular repair of damaged structures, and to soft tissue reconstruction following massive foreign body injuries.  相似文献   
89.
Lymphocytes were cultured from cardiac biopsies following heart transplantation using interleukin-2-conditioned medium. Using the technique of limiting dilution analysis the frequency of donor specific cytotoxic T lymphocytes was measured in cells cultured from biopsies and compared with that in peripheral blood lymphocytes taken at the same time as the biopsy. The graft cell population showed a considerably higher frequency of donor-specific CTL when compared with the PBL. CTL frequencies in the graft cells were always higher against the donor than against third-party cells. These data demonstrate that there was either selective sequestration or selective expansion of donor-reactive T cells in the heart following cardiac transplantation. These results emphasize the need to investigate more closely the events occurring in the heart, and may explain the lack of specificity and sensitivity in immune monitoring (IM) or cytoimmune monitoring (CIM) seen in many centers.  相似文献   
90.
Epidermal growth factor (EGF)-related polypeptides may be involved in the growth of human prostate cancer cells, and in the androgen stimulation of hormone-responsive prostatic carcinomas. We have shown that androgen-responsive LNCaP cells, like the autonomous DU 145 human prostate cancer cell line, synthesize and secrete EGF and related polypeptides, including immunoreactive transforming growth factor-alpha (TGF-alpha). As determined by radioimmunoassay, intracellular EGF levels were approximately 100 times those of TGF-alpha, but together these accounted for less than half of the total EGF-like polypeptides detected in a radioreceptor assay. Although LNCaP cell growth was stimulated by dihydrotestosterone (DHT), there was no evident effect on immunoreactive EGF levels in the medium after correction for cell number. Moreover, metabolic labeling experiments showed no effect of the androgen on EGF synthesis by LNCaP cells. Gel filtration chromatography of conditioned medium showed both high molecular weight species and the mature 6,000 dalton form of immunoreactive EGF. We conclude that although LNCaP prostate cancer cell growth is stimulated by DHT, it is unlikely that it is mediated directly via increased EGF synthesis by the tumor cells.  相似文献   
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