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871.
872.
An intravenous (iv) radiofrequency (RF) coil is proposed as a means of obtaining high resolution images of artery wall. The anatomic positioning of peripheral artery/vein pairs was investigated and a phantom mimicking the iliac artery/vein pair was constructed. Imaging results, comparing iv coils with external coils, demonstrated a potential 15- to 20-fold increase in signal-to-noise ratio (SNR) with iv coils. The SNR benefit was measured over a cylindrical volume, adjacent to the coil, and typical of artery position. Prototype expandable iv coils were constructed of Cu-Be loops and introduced via an 8-Fr catheter. The effects of local and remote iv coil tuning were investigated and local tuning was found to provide significant SNR benefits. The in vivo performance of iv RF coils was demonstrated in a porcine animal model. The iv coils were found to be an excellent alternative to intraarterial coils.  相似文献   
873.
BACKGROUND: Problems with the provision of palliative care have been reported. Audit is one means of improving care. Earlier audits of primary care palliative care have been initiated by general practitioners (GPs) and are predominantly retrospective record reviews. Widely applicable methods for the audit of primary care palliative care do not exist. AIM: To develop relevant palliative care standards and to devise an audit schedule (the Cambridge palliative audit schedule, CAMPAS) suitable for monitoring palliative care in diverse primary care settings. METHOD: Primary health care team (PHCT) members collaborated at all stages. Reasonable outcomes and acceptable interventions for PHCTs were identified and standards developed. Each standard was constructed to ensure uniform interpretation, and CAMPAS was structured to collect data necessary for determining whether the standards were met. RESULTS: Over 50% of PHCTs (n = 20) in the health district were recruited and trained to use CAMPAS. A total of 876 contacts with 29 patients was recorded by PHCTs using CAMPAS. Considerable inter- and intra-PHCT variation was found in the achievement of the standards. CONCLUSIONS: The favourable participation rate suggests commitment to audit and improvement in patient care. Overall, the standards were reported to be suitable. Although 100% achievement of some standards may be unrealistic, the level of attainment for many suggests that it is possible. CAMPAS has been reported to be a useful structure for recording assessments and monitoring care, as well as a usable audit schedule. As an audit tool, it identified areas in need of improvement and facilitated feed-back to participants. Future audit is required to determine whether improvements in care have been effected.  相似文献   
874.
The Nef protein of HIV-1 binds to and induces apoptotic cytolysis of uninfected but activated human peripheral blood mononuclear cells (PBMC) and various cell line cells derived from CD4+ T, CD8+ T and B lymphocytes, macrophages, and neutrophils. The Nef-induced apoptosis also occurs with blood cells not expressing CD95 (Fas). The Nef-induced apoptosis as well as Fas-mediated apoptosis was inhibited by acetyl-Try-Val-Ala-Asp-CHO, an IL-1beta converting enzyme (ICE) inhibitor. On the other hand, serine/threonine protein kinase (PK) inhibitors, H-7, fasudil hydrochloride and M3, inhibited the Nef-induced apoptosis, and not the Fas-mediated one, without affecting the cell-binding activity of Nef and Nef-binding capacity of the activated cells. Preincubation of the cells with the drugs before being bound by Nef was required for the inhibition of apoptosis. These results suggest that the PK inhibitors specifically act on a cellular protein involved in the upper stream of signal transduction pathway of the Nef-induced apoptosis, which is different from the Fas-mediated pathway but meets it upstream of ICE. In addition, the drugs suppressed the cellular activation-associated cell surface expression of a putative Nef-binding protein in PBMC, although they had no influence on its expression in cell line cells. These findings suggest the feasibility of clinical use of the PK inhibitors to prevent the development of AIDS by inhibiting the Nef-induced apoptosis of uninfected blood cells.  相似文献   
875.
We hypothesized that cellular oxygen consumption is abnormal during sepsis as a result of increased oxidative stress and selective mitochondrial damage. In a rat model of sepsis (cecal ligation and puncture), we studied the respiratory characteristics of isolated hepatocytes and liver mitochondria 16 h after onset of septic injury. Endogenous respiration by isolated cells was decreased during sepsis, while cyanide-resistant (nonmitochondrial) respiration was unaffected. Maximal oxygen consumption in ADP-supplemented, permeabilized hepatocytes was decreased with succinate as the substrate, but not with malate + glutamate or TMPD + ascorbate. In contrast, maximum oxygen consumption (State 3) by isolated liver mitochondria increased up to 35% during sepsis using either succinate or malate + glutamate as substrate. The electrophoretic features and mobility of nondenatured mitochondrial respiratory complexes were similar in control and septic hepatocytes, with the exception of decreased Complex V protein in sepsis. Structural evaluation of mitochondria in fixed liver slices by electron microscopy showed mitochondrial swelling in most of the septic animals. Measurements of oxidative stress during sepsis suggested an increase in hydroxylation of salicylate by isolated hepatocytes, and mitochondrial protein carbonyl content was increased significantly. Induction of iNOS in hepatocytes after 16 h of sepsis was variable, and little release of the oxidation products of NO. was detected. These findings are interpreted to mean that hepatocytes contain a mixed population of injured and hyperfunctional mitochondria during sepsis.  相似文献   
876.
In a series of four experiments, the effects of differences in dietary protein intake on BW, skeletal growth and the weight of the Pectoralis major muscle was studied in Hubbard Standard and Hubbard Hi-Y broiler breeder pullets. In Experiment 1, pullets were fed diets with either 15, 17, or 19% CP from 1 to 21 d. There was a linear increase in BW gain and feed consumption with each increase in CP and Hubbard Standard pullets consumed significantly more feed than Hubbard Hi-Y pullets. From 21 to 34 d, pullets were subjected to feed restriction every day (ED) or every-other-day (EOD). On Day 35, pullets were given ad libitum access to feed and ED-restricted pullets consumed significantly more feed than EOD-restricted pullets through 3.5 h postfeeding. In Experiment (Exp.) 2, pullets were fed the 19% CP diet for approximately 14 d (300 g) or 20 d (600 g) before being switched to the 15% CP diet. In Experiment 3, the 19% CP diet was fed for exactly 7 or 21 d before switching to the 15% CP diet. In all experiments, Hubbard Standard pullets weighed significantly more than Hubbard Hi-Y pullets and had increased overall skeletal growth. When the pullets from both strains were restricted to only 380 g BW at 28 d, (Exp. 3) the longer period of protein intake significantly enhanced breast muscle weight but there were no significant strain differences. When BW at 28 d was increased to 480 g, (Exp. 2), dietary protein and strain differences were observed.  相似文献   
877.
The aim of the work was investigation of both efficacy of sulpiride, atypical neuroleptic drug with pronounced antidepressive activity, and its influence on central nervous system. The study was performed in the course of prophylactic treatment of migraine using contingent negative variation (CNV) index. It is demonstrated that sulpiride is effective in prophylactic treatment of migraine complicated with psychologic disorders and autonomic dysfunctions. Such effect may be caused by the drug's influence on depression, anxiety, autonomic symptoms, tension-type headaches. This conclusion was confirmed by CNV data, change of which after sulpiride administration have indicated normalization of mental performance and increase of active adaptive abilities.  相似文献   
878.
879.
1. The role of the adhesion glycoproteins CD18 and intercellular adhesion molecule-1 (ICAM-1) in inflammatory responses produced during a reversed passive Arthus (RPA) reaction and induced by zymosan and zymosan-activated plasma (ZAP) were studied in rabbit skin. 2. Oedema formation and haemorrhage were quantified by measuring accumulation of 125I-albumin and 111In-labelled red blood cells (111In-RBC) respectively. 3. Monoclonal antibody (mAb) R15.7 (anti-CD18), administered intravenously, abolished accumulation of 125I-albumin and 111In-RBC in dermal RPA reactions and in response to locally injected zymosan and ZAP. 4. When administered intravenously, the mAb RR1/1 (anti-ICAM-1) suppressed 125I-albumin and 111In-RBC accumulation in dermal RPA reactions and at sites treated with zymosan and ZAP. 5. Oedema formation in response to platelet-activating factor (PAF) and bradykinin (BK) either in the presence or absence of prostaglandin E2 (PGE2) were not affected by mAb R15.7 or by mAb RR1/1.1.1. 6. We conclude that oedema formation and haemorrhage associated with RPA reactions and in responses to zymosan and ZAP are completely CD18-dependent, and are mediated, at least in part, via ICAM-1. Responses to the neutrophil-independent oedema forming mediators, PAF and BK are not dependent upon CD18 or ICAM-1.  相似文献   
880.
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