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21.

Introduction

The protective effect of glutamine, as a pharmacological agent against lung injury, has been reported in experimental sepsis; however, its efficacy at improving oxygenation and lung mechanics, attenuating diaphragm and distal organ injury has to be better elucidated. In the present study, we tested the hypothesis that a single early intravenous dose of glutamine was associated not only with the improvement of lung morpho-function, but also the reduction of the inflammatory process and epithelial cell apoptosis in kidney, liver, and intestine villi.

Methods

Seventy-two Wistar rats were randomly assigned into four groups. Sepsis was induced by cecal ligation and puncture surgery (CLP), while a sham operated group was used as control (C). One hour after surgery, C and CLP groups were further randomized into subgroups receiving intravenous saline (1 ml, SAL) or glutamine (0.75 g/kg, Gln). At 48 hours, animals were anesthetized, and the following parameters were measured: arterial oxygenation, pulmonary mechanics, and diaphragm, lung, kidney, liver, and small intestine villi histology. At 18 and 48 hours, Cytokine-Induced Neutrophil Chemoattractant (CINC)-1, interleukin (IL)-6 and 10 were quantified in bronchoalveolar and peritoneal lavage fluids (BALF and PLF, respectively).

Results

CLP induced: a) deterioration of lung mechanics and gas exchange; b) ultrastructural changes of lung parenchyma and diaphragm; and c) lung and distal organ epithelial cell apoptosis. Glutamine improved survival rate, oxygenation and lung mechanics, minimized pulmonary and diaphragmatic changes, attenuating lung and distal organ epithelial cell apoptosis. Glutamine increased IL-10 in peritoneal lavage fluid at 18 hours and bronchoalveolar lavage fluid at 48 hours, but decreased CINC-1 and IL-6 in BALF and PLF only at 18 hours.

Conclusions

In an experimental model of abdominal sepsis, a single intravenous dose of glutamine administered after sepsis induction may modulate the inflammatory process reducing not only the risk of lung injury, but also distal organ impairment. These results suggest that intravenous glutamine may be a potentially beneficial therapy for abdominal sepsis.  相似文献   
22.
Methanol intoxication, a rare and potentially lethal form of poisoning, usually results from ingestion and occasionally inhalation of methanol. Initial symptoms of blurred vision, elongated anion gap and metabolic acidosis are typically delayed and may not at first be recognised as methanol-related complaints. Once diagnosed, treatment must be prompt and definitive. As well as general supportive care, ethanol infusion, dialysis and alkalinization form the mainstays of treatment.

The cases described in this paper are compared to previous reports from other countries worldwide and contrast the variance in outcome often seen in methanol poisoning. The paper describes two tragic deaths and two lucky survivors, all of whom had consumed a cocktail of methanol and other alcoholic beverages at the same party.

The ICU nurse's role in managing the methanol-intoxicated patient relies on that person's sound knowledge of the unusual biochemical reactions occurring in the body and the need to institute definitive and supportive measures to help both patient and family recover.  相似文献   

23.
24.
BACKGROUND: Platelets become activated during storage, which results in secretion of granules, vesiculation of microparticles, secretion of protein, and a number of other biochemical and morphologic processes that decrease the utility of platelet concentrates stored for transfusion. STUDY DESIGN AND METHODS: To evaluate the quality of stored platelet concentrates, the cell surface expression of specific activation-dependent antigens (CD62 and lysosome-associated membrane proteins 1 and 2 [LAMP-1, LAMP-2]) on platelets stored in a hospital blood bank over a 7-day period was examined. Relative microparticle counts and the expression of CD62 by microparticles, as well as platelet concentrate supernatant levels of soluble CD62, were determined. RESULTS: The percentage of platelets expressing CD62 increased significantly from Day 1 to Day 5 (p < 0.05) of storage; the mean fluorescence values for CD62 did not. In contrast, the mean fluorescence values of LAMP-1 and LAMP-2 rose significantly (p < 0.01 and p < 0.05, respectively) between Days 1 and 5. Significant declines in CD62, LAMP-1, and LAMP-2 percent expression and mean fluorescence were seen on Day 6 of storage (p < 0.001). Microparticle numbers increased significantly during storage and correlated with levels of CD62 protein (free and membrane-bound) (r = 0.95 vs. Day 2, p < 0.05; r = 0.88 vs. Day 5, p < 0.05). CONCLUSION: Flow cytometric evaluations of the expression of cell surface CD62, LAMP-1, and LAMP-2 are complementary tests that, especially when used in conjunction with the quantitation of CD62 protein, provided a simple and effective means of evaluating the quality of platelet concentrates stored for transfusion.  相似文献   
25.
Clinical role activities of nurse teachers in Project 2000 programmes   总被引:1,自引:0,他引:1  
This paper presents the findings related to the clinical role activities of nurse teachers in Project 2000 programmes Data were collected by a Delphi survey of 25 colleges of nursing that had implemented Project 2000 between September 1989 and April 1991 The findings from the Delphi survey were explored more fully through in-depth interviews with a sample of the respondents The findings identified a very strong commitment of the respondents to a clinical liaison role But they did not perceive their role to be one of teaching students through 'hands on care', they felt this was the role of the qualified staff in the clinical areas The respondents considered it important to maintain their clinical credibility through theoretical updating rather than being able to perform as an expert practitioner  相似文献   
26.
The equity debate within the British National Health Service   总被引:1,自引:0,他引:1  
The equity debate within the British National Health Service This paper begins by identifying the principles of equity and fairness on which the British National Health Service (NHS) was founded in 1948. It then goes on to summarize the viewpoints of those who more recently have argued that equity is an out-moded, Utopian and unachievable concept that should not be applied to the delivery of health care services. A brief review is conducted of the definitions of equity and inequity as these apply to health care. Brief attention is paid to the relationship between equitable distribution of health care and social class. The new contemporary significance of equity for all NHS managers is exposed through a debate concerning the impact of the recently introduced policies for the implementation of a quasi-market in health services in Britain. The inseparable relationship between equity and the rationing of resources is identified as central to the just distribution of health care. The paper presents evidence that the quasi-market solutions to improved economic efficiency and cost-containment are often in direct conflict with the equity doctrine on which the NHS was created. A brief conclusion how equity principles might be restored to health policy is proffered.  相似文献   
27.
The aim of the present study was to examine the use of maternal weight measurements during antenatal care throughout the United Kingdom. A postal questionnaire and follow-up letter were sent to 1500 midwives throughout the United Kingdom, selected at random from the UKCC register. The postal survey achieved a response rate of 44.8% (672/1500 questionnaires), and obtained responses from at least 10 midwives in all but the lowest grade. Respondents were representative of midwives practising throughout the country, in terms of their gender, working hours and grade, although there were fewer midwives in community settings than those in a contemporary representative English sample. The questionnaire obtained information on the background, training and experience of each midwife, together with their attitudes towards antenatal weighing. For those midwives currently involved in antenatal care, additional information was collected on the schedule of antenatal weight measurements, the criteria used to identify ‘abnormal’ weight gain, and the action taken in response to ‘abnormal’ weight gain. 61.8% of the midwives thought that the pattern of maternal weight gain was ‘not important’ in antenatal care, and only 51.5% of those who currently provided antenatal care weighted women at every antenatal visit. However, most midwives (86.1%) cited at least one clinical condition to explain why women are routinely weighed during pregnancy, and over a third of midwives thought that maternal weight gain could detect seven clinical conditions, including obesity, oedema, pre-eclampsia and polyhydramnios. Midwives with more advanced qualifications (degrees and teaching qualifications) and those working in educational or community settings were least likely to believe that weight gain was good at detecting clinical outcomes. Differences in the perceived utility of antenatal weighing influenced whether midwives would act in response to ‘abnormal’ maternal weight gain, and whether they advised women to gain or lose weight during pregnancy. However, the criteria that midwives used for identifying ‘abnormal’ weight gain were variable, and often inappropriate, so that different midwives are unlikely to intervene consistently or to give consistent advice on the basis of maternal weight gain. These differences in practice may lead to extensive and inappropriate variation in antenatal care. Clear guidelines are urgently required to ensure that, if maternal weight measurements are collected during antenatal care, they are collected and used consistently.  相似文献   
28.
The development of instruments to measure clinical competence in nursing shows little evidence of a systematic approach and studies of reliability and validity are absent. The present study was carried out using data on practice assessment collected in the course of a post-registration nursing programme. The data were analysed for internal consistency and intra-rater reliability. The instrument used to assess practice in the present study is highly internally consistent and there is evidence to support intra-rater reliability. However, further development and testing of the instrument is required.  相似文献   
29.
Respiratory insufficiency in neuronopathic and neuropathic disorders   总被引:1,自引:0,他引:1  
Twenty-nine patients with a neuronopathic or neuropathic disorder were referred for assessment of respiratory insufficiency between 1978 and 1994. Diagnoses included spinal muscular atrophy (6), chronic idiopathic demyelinating neuropathy (4), Vialetto-van Laere syndrome (3), hereditary motor and sensory neuropathy (3) and a miscellaneous group (5). We also describe seven patients with Guillain-Barre syndrome (GBS) who required long-term ventilatory support for over 6 months to 7 years after the initial illness. Respiratory insufficiency occurred as a consequence of respiratory muscle weakness, impaired bulbar function and restrictive lung defects. In some groups presentation was with progressive nocturnal hypoventilation culminating in acute respiratory failure. Five patients with GBS or chronic idiopathic demyelinating neuropathy were weaned from ventilatory support up to 18 months after the initial illness. The remaining 24 patients required continuous or nocturnal ventilatory support using intermittent positive-pressure ventilation (13), negative pressure ventilation (4), nasal-mask-delivered intermittent positive-pressure ventilation (4), nasal-mask-delivered continuous positive-pressure ventilation (3), mouthpiece-assisted ventilation by day (2) and rocking bed (1). None have been weaned from support after a period of ventilation ranging from one month to 10 years. Eight patients have subsequently died.   相似文献   
30.
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