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91.
The purpose of our study was to test the hypothesis that the quotient between plasma glucose and whole body oxygen consumption (VO2) as a 'metabolic index' is a sensitive indicator of early graft function. Arterial levels of glucose and oxygen consumption were determined in 100 consecutive patients during orthotopic liver transplantation performed without anhepatic veno-venous bypass. Patients were divided into survivors with no obvious problems related to graft function and those with primary nonfunction of the graft. The neohepatic increase in VO2 was significantly higher in survivors (112 +/- 4 vs 88 +/- 11 ml.min-1.m-2; p < 0.05), whereas blood glucose levels after reperfusion were higher (352 +/- 18 vs. 287 +/- 36 mg dl-1) in those with primary non-function of the graft. The calculated metabolic index was also higher (4.02 +/- 0.93 vs 2.67 +/- 0.45, p < 0.05) in patients with primary nonfunction of the graft. Our principal conclusion was that 92% of normal functioning liver grafts could be classified correctly by the metabolic index immediately after reperfusion, whereas glucose levels and VO2 alone classified only 67% and 70% of normal functioning liver grafts correctly. 相似文献
92.
C H Muller 《Journal of andrology》1992,13(5):349-360
Assuring the highest possible quality of care to the patient is the first goal of the andrology laboratory. Quality control and quality assurance as they apply to the andrology laboratory are outlined, and special problems in quality control for sperm function assays are addressed. An example of the patient review process is presented. Quality of care also depends on the ability of the laboratory to perform appropriate tests of sperm function that can diagnose sperm defects, predict success or failure of in vitro fertilization, and lead to rational therapies for sperm dysfunctions. Methods for, and diagnostic value of, sperm swim-out, enhanced sperm penetration assays, acrosome reaction assessment, motility analysis of capacitating sperm, and sperm-zona binding assays are reviewed. No single test, other than in vitro fertilization itself, is capable of providing a complete diagnosis or a highly accurate prediction. A battery of sperm function tests, arranged in an algorithm, is presented as a theoretically better approach. 相似文献
93.
94.
A randomized controlled trial of sedation in the critically ill 总被引:2,自引:0,他引:2
LYNN PARKINSON RSCN JULIE HUGHES RSCN REA GILL MSc IMOGEN BILLINGHAM BM FRCA JANE RATCLIFFE MB ChB FRCP & IMTI CHOONARA MD MRCP 《Paediatric anaesthesia》1997,7(5):405-510
A randomized controlled trial comparing: a) a combination of oral chloral hydrate and promethazine to b) a continuous intravenous midazolam infusion, for maintenance sedation in critically ill children, was carried out. The level of sedation was assessed four hourly using a specifically devized sedation scale. Forty-four children entered the study of whom two were subsequently excluded. The number of satisfactory assessments (desired and actual levels of sedation equal) was significantly greater in the chloral hydrate and promethazine group (Chi-squared P <0.01; confidence intervals of the difference 0.06 to 0.20). The number of assessments at level 5 on the sedation scale (patient restless/distressed) was significantly greater in the midazolam group (Chi-squared P <0.05). The total number of satisfactory assessments in the two groups were only 61 and 48% respectively, suggesting that sedation can be considerably improved. Chloral hydrate and promethazine are more effective than midazolam as maintenance sedation in critically ill children. It is possible to prospectively study the efficacy of sedative drugs in critically ill children. 相似文献
95.
H J Muller D Lanens T J de Cock Buning F L van de Vyver F C Alderweireldt R Dommisse M Spanoghe G J Mulder J Lugtenburg 《Drug metabolism and disposition》1992,20(4):507-509
Noninvasive NMR methodology has been developed to enable monitoring of 13C-labeled xenobiotics in the rat in vivo. 2,2-Dichloro-1-(2-chlorophenyl)-1-(4-chlorophenyl)-[3-13C]-propane can be detected in the liver of intact rats by in vivo 13C surface coil NMR spectroscopy after ip administration of the compound. The experiments were performed at 1.9 and 9.4 Tesla. The intrahepatic changes of the signal intensity of the labeled compound were followed as a function of time. In the days following administration, the concentration decreased and dropped to values below the detection limit after 12 days. The study demonstrates the feasibility of studies on pharmacokinetics of 13C-labeled compounds in the rat using noninvasive, in vivo surface coil NMR spectroscopy in animals. The sensitivity allows the detection of a single dose of the drug of 200 mg/kg, but can be improved. 相似文献
96.
Promoting autonomy and independence for older people within nursing practice: a literature review 总被引:1,自引:0,他引:1
Sue Davies Bsc Msc RGN RHV Sara Laker BA RGN Lorraine Ellis BA MSc RGN RNT 《Journal of advanced nursing》1997,26(2):408-417
The principles of promoting autonomy and independence underpin many approaches to improving the quality of nursing care for older people in whatever setting, and are in line with wider developments in health care such as the Patient's Charter. However, these concepts require careful definition if nursing practices which might promote autonomy and independence are to be identified. Although the generalizability of the research-based literature in this field is limited by a focus upon older people in continuing-care settings, a review of the literature found a number of indicators associated with attempts to promote patient autonomy and independence. These were grouped into the following categories: systems of care delivery which promote comprehensive individualized assessment and multidisciplinary care planning; attempts to encourage patients/clients to participate in decisions about their care; patterns of communication which avoid exerting power and control over patients/clients and attempts to modify the environment to promote independence and minimize risk. It is suggested that the review identifies a number of principles for nursing practice which can be applied in a range of care settings in order to promote the autonomy and independence of older people. 相似文献
97.
98.
Since the 1960s conventional crop breeding has increased food production commesurate with the growing population. For agricultural development to continue, the exploitation of greater genetic diversity and modern biotechnology are becoming increasingly important. This article reviews the milestones achieved by the Green Revolution and many of the recent breakthroughs of modern biotechnology. 相似文献
99.
Fibroblast subpopulations in intra-oral wound healing 总被引:3,自引:0,他引:3
Hugo E. Van Beurden MSc ; Patricia A.M. Snoek BAC ; Johannes W. Von Den Hoff PhD ; Ruurd Torensma PhD ; Anne-Marie Kuijpers-Jagtman DDS PhD 《Wound repair and regeneration》2003,11(1):55-63
The objective of this study was to characterize fibroblasts at sequential time points during intra-oral wound healing in the rat. Experimental wounds were made at several time points in the mucoperiosteum of the palate of 35-day-old Wistar rats. Fibroblasts were cultured from the biopsies under standard conditions for the same number of passages. The expression of the integrin subunits alpha 1, alpha 6, and beta 1; and the intermediate filaments alpha-smooth muscle actin and vimentin were analyzed by flow cytometry. Western blot analysis was performed at 0, 8, and 60 days postwounding to confirm the expression of both intermediate filaments. The phenotypic profiles of fibroblasts cultured from subsequent stages in the wound healing process differed considerably. We conclude that distinct fibroblast phenotypes can be isolated from different stages in wound healing. These phenotypes remained stable during in vitro culturing. In addition, cryosections of the wound areas were made at identical time points and were immunohistochemically stained for the same antigens. The immunohistochemical staining correlated well to the flow-cytometric data. These results suggest the occurrence of multiple subpopulations of fibroblasts with a specialized function during wound healing. We hypothesize that undesirable consequences of wound healing might be prevented through the modulation of specific fibroblast subpopulations. 相似文献
100.
Migraine is 3 times more common in postpubertal women than in men. Migraine is frequently exacerbated perimenstrually and commonly occurs exclusively at that time. It is often benefited by pregnancy and menopause. Estrogen withdrawal has been implicated as a mechanism for triggering migraines. The mechanism, however, is not well understood. Reproductive steroids have neuroactive properties that can modulate neuronal morphology and physiology. Increasing evidence suggests that circulating reproductive steroid levels regulate the balance of neuroexcitatory and neuroinhibitory activities in some brain regions by influencing synaptic plasticity. Estrogen has neuroexcitatory, whereas progesterone has neuroinhibitory, effects in most preclinical and clinical models. Several neurotransmitter systems that are implicated in migraine vary with reproductive steroid levels during the reproductive cycle. Estrogen stabilization may provide effective treatment in susceptible women, especially for catamenially exacerbated migraine. 相似文献