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991.
Capillary electrophoresis is applied to determine nucleotide pool levels in human Burkitt lymphoma cells. The analysis was performed on a 65 cm x 50 microns I.D. Ucon-coated column with on-column UV detector. The method requires only nanoliters of sample and a simple sample preparation procedure. Over 12 nucleotides were separated and quantitated with high resolution and reproducibility. The whole capillary electrophoretic separation time was only 35 min. These results demonstrate that capillary electrophoresis provides a useful and easy way to analyze nucleotide pools in cells.  相似文献   
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OBJECTIVE: To investigate the management of the bereaved on Intensive Care Units (ICU) throughout the United Kingdom, and to identify inadequacies that may exist either in the provision of staff training in dealing with bereavement or in the facilities or support available for the bereaved. DESIGN: Questionnaires were sent to the senior nurse and senior doctor in all general ICUs with more than four beds nationwide. The questions asked about nursing and medical practice around the time of a patient's death, as well as about staff attitudes towards, and training in, dealing with bereavement and the support they received for this role. RESULTS: We obtained a 68% (293/430) response rate. Most ICUs had facilities for relatives, but little for the specific needs of the bereaved. Only 6% of doctors and 21% of nurses had training in dealing with bereavement and grieving. A staff support group was available in 23% of ICUs, and 75% of the remainder thought it would be useful to have one. Lack of staff training and poor facilities for relatives were identified as the major concerns of ICU staff. CONCLUSION: Many doctors and nurses working in Intensive Care Units feel inadequately trained to deal confidently with the bereaved. A minority of ICUs have support mechanisms available for their staff, inspite of the perceived need for them. Furthermore, many ICU staff feel the facilities they are able to offer the bereaved are inadequate. We have identified the major inadequacies and the needs of ICU staff for improved training. Meeting these needs would play a significant role not only in reducing staff stress but also minimising the morbidity in surviving relatives.  相似文献   
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Polypeptide hormones and growth factors have long been known to internalize into peripheral target cells as a result of their interaction with cell surface receptors. Studies in culture have suggested that certain neuropeptides might undergo a similar type of translocation in neurons. To investigate this possibility in adult mammalian brain, we have examined by confocal laser microscopy the events that follow the binding of fluorescein-tagged derivatives of the tridecapeptide neurotensin to basal forebrain cholinergic cells. Our results demonstrate a selective time- and temperature-dependent internalization of fluo-neurotensin in these cells. This internalization is receptor mediated, proceeds from the entire somatodendritic membrane of the cells, and utilizes endosome-like organelles which are mobilized from dendrites to perikarya and from the periphery of the cell to its perinuclear region. Parallel studies carried out on Sf9 insect cells expressing the rat neurotensin receptor from a recombinant baculovirus indicated that the internalization process involves receptor-ligand complexes and not merely the fluorescent peptide itself. These data suggest that receptor internalization plays a role in neuropeptide signaling in the brain and that it can be harnessed for selective identification of neuropeptide target cells.  相似文献   
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The parasympathetic nervous system plays a major role in the pathophysiology of many cardiovascular disease, particularly in modulating myocardial electrical stability. Measurements of heart rate variability have been widely used to assess parasympathetic activity. The reproducibility of measurements obtained from 24-hour ambulatory electrocardiograms has not been well documented. We have developed a technique for measuring parasympathetic activity from clinical quality 24-hour ambulatory electrocardiograms by counting beat-to-beat increases in RR interval that are > 50 ms. To determine the reproducibility and sensitivity of our technique, we analyzed repeated 24-hour electrocardiograms of 173 subjects (19 normal subjects, 67 patients with ischemic heart disease, and 87 diabetics) followed up over periods of 2 to 16 weeks. In all subject groups, mean values for repeated measurements were virtually identical. Measurements were stable in all 3 groups throughout the course of the study, as assessed by intraclass correlation coefficients. This technique is sensitive enough to detect relatively small changes in parasympathetic activity in subjects, as demonstrated by the calculated Bland and Altman coefficients of repeatability. Reproducibility and sensitivity of our technique are particularly good in normal subjects and in patients with ischemic heart disease. The results obtained with this technique imply that other related measurements of parasympathetic activity will show similar excellent short- and long-term reproducibility and sensitivity.  相似文献   
999.
Arrestins are members of a superfamily of regulatory proteins that participate in the termination of G protein-mediated signal transduction. In the phototransduction cascade of vertebrate rods, which serves as a prototypical G protein-mediated signaling pathway, the binding of visual arrestin is stimulated by phosphorylation of the C-terminus of photoactivated rhodopsin (Rh*). Arrestin is very selective toward light-activated phosphorhodopsin (P-Rh*). Previously we reported that a single amino acid substitution in arrestin, Arg175Gln, results in a dramatic increase in arrestin binding to Rh* [Gurevich, V. V., & Benovic, J. L. (1995) J. Biol. Chem. 270, 6010-6016]. Here we demonstrate that a similar mutant, arrestin(R175E), binds to light-activated rhodopsin independent of phosphorylation. Arrestin(R175E) binds with high affinity not only to P-Rh* and Rh* but also to light-activated truncated rhodopsin in which the C-terminus phosphorylation sites have been proteolytically removed. In an in vitro assay that monitored rhodopsin-dependent activation of cGMP phosphodiesterase (PDE), wild type arrestin quenched PDE response only when ATP was present to support rhodopsin phosphorylation. In contrast, as little as 30 nM arrestin(R175E) effectively quenched PDE activation in the absence of ATP. Arrestin(R175E) had no effect when the lifetime of Rh* no longer contributed to the time course of PDE activity, suggesting that it disrupts signal transduction at the level of rhodopsin-transducin interaction.  相似文献   
1000.
This study evaluated the associations between intimacy, quality of life, and sexual dysfunction in men and women. Participants were 145 sexually functional (43 men, 102 women) adults drawn from the general population and 198 sexually dysfunctional (114 men, 84 women) adults who came to a university sexual behavior clinic. All respondents were currently involved in a heterosexual relationship. Respondents completed a series of questionnaires to evaluate the level of intimacy in their relationships, their quality of life, and their level of sexual dysfunction. All aspects of intimacy were lower among sexually dysfunctional men than among sexually functional men for all subgroups of dysfunctionality (premature ejaculation, erectile failure, and lack of sexual desire). Levels of intimacy were less likely to discriminate between functional and dysfunctional women, with functional women only obtaining higher intimacy scores than each of the dysfunctional groups of women (inorgasmia, lack of arousal, lack of sexual desire) for social intimacy and recreational intimacy and, to a lesser extent, for sexual intimacy. Objective levels of quality of life as well as the satisfaction and importance of the quality of life domains were more likely to be lower when sexually dysfunctional women were compared with their functional counterparts than when sexually dysfunctional men were compared with their functional counterparts. The implications of these findings for an understanding of factors that contribute to sexual dysfunction, and the treatment of these disorders, is discussed.  相似文献   
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