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51.
In a clinical judgement analysis, we used linear regression models to reflect the impact of clinical and non-clinical cues on priority decisions, by comparing the stated prioritization policies of 30 clinicians with their actual policies as revealed by an appraisal of 50 'paper patients'. Correspondence was modest for some cues, e.g. 25 doctors said they accounted for age, but age only had a significant bearing in the derived decision models of two doctors. Correspondence between the derived and expressed weights was greatest for clinical angina grade and the presence of left main stem stenosis. Correlation between the rank order of importance between the two models was poor for most of the cues, and statistically significant only for smoking. However, stated policies made it appear that lifestyle factors such as smoking habit would influence prioritization decisions for most clinicians but policies derived from actual prioritization decisions seldom related to lifestyle or demographic variables. There were significant differences in the degree of correlation between the two models according to the experience of the clinician. However, correspondence was not significantly better for doctors with cardiological training than those without. The overall contribution of demographic and lifestyle factors to decision making appears to be small, suggesting that they should be omitted from prioritization guidelines.   相似文献   
52.
Background Perceived age is important to women and is a primary driver for topical product use and facial cosmetic surgery. Changes in facial features and biophysical skin parameters with chronological age and their associations with perceived age have not been described in Asian populations. Objective To investigate the relationship between biophysical properties of the skin, visual features of skin ageing and perceived facial age in Chinese women. Methods Facial photographs were collected of 250 Chinese women, aged 25–70 years in Shanghai, China. The perceived facial age was determined and related to the chronological age for each participant and to a range of visual assessments of skin appearance and objective biophysical measurements of the skin. The profile of changes in these parameters with age was investigated together with the differences in those parameters for women judged to look younger than their chronological age and those judged to look older than their chronological age. Results Large discrepancies in perceived age (up to 29 years) were found in women of the same chronological age. Each objective skin measure and visual assessment parameter had a stronger correlation with perceived age than with chronological age. The strongest relationships to perceived age were for wrinkles and hyperpigmentation. Skin colour, hydration and trans‐epidermal water loss (TEWL) had weaker associations with perceived age. Women judged to look older than their chronological age had significantly higher scores than those judged to look younger for coarse wrinkles and hyperpigmentation across all age groups. The appearance differences between these groups were evident in composite facial images of the same average chronological age. Conclusions We have identified the skin attributes which differ with perceived age in Chinese women. Perceived age is a better measure of the biological age of facial skin than is chronological age in this population.  相似文献   
53.
目的:观察妇科开腹手术患者术前给予依他昔布120mg对术后自控镇痛(PCA)吗啡用量的影响及其副作用。方法:随机选取全麻下接受妇科开腹全子宫(双附件)切除患者40例,术前分别给予安慰剂或依他昔布120mg口服。在手术后观察24h患者PCA吗啡用量,同时记录患者的疼痛评分和满意度评分,并观察不良反应。结果:术后PCA吗啡24h消耗量在依他昔布组为9.4±7.6mg,显著低于安慰剂组15.7±8.9mg。两组患者24h内对PCA的按压次数依他昔布组也低于安慰剂组(P<0.05)。其中术后3、6、8和12hPCA吗啡消耗量在两组间无显著差异。两组患者术后24h疼痛评分和对镇痛治疗的满意度也无差异。两组患者不良反应的发生率亦无差别。结论:在妇科开腹手术患者术前应用依他昔布120mg可使患者术后PCA吗啡消耗量降低,且在术后12h后下降明显。未发现与依他昔布应用相关的副作用。  相似文献   
54.

Background  

Potassium disorders can cause major complications and must be avoided in critically ill patients. Regulation of potassium in the intensive care unit (ICU) requires potassium administration with frequent blood potassium measurements and subsequent adjustments of the amount of potassium administrated. The use of a potassium replacement protocol can improve potassium regulation. For safety and efficiency, computerized protocols appear to be superior over paper protocols. The aim of this study was to evaluate if a computerized potassium regulation protocol in the ICU improved potassium regulation.  相似文献   
55.

Background

Acute ischemic stroke diagnosis and treatment are among the most challenging in Emergency Medicine. Perfusion computed tomography (CTP) can increase the sensitivity for detecting ischemic stroke and, especially with the addition of CT angiography (CTA), improve decision-making regarding thrombolytic therapy compared to non-contrast computed tomography (NCCT) alone. However, because acute stroke protocols do not generally include procedures for multimodal imaging, they are not commonly performed. In addition, there is concern that additional studies could delay or preclude therapy in patients otherwise eligible for thrombolytic therapy.

Objectives

To demonstrate the feasibility of perfusion CTP and CTA in addition to NCCT of the brain in the emergency assessment of patients with acute ischemic stroke. Methods: Starting January 2008, multimodal (CTP and CTA) imaging was added to NCCT in the Emergency Department (ED) initial assessment of patients with stroke of ≤ 5 h duration. Over the subsequent 9 months, we measured the time from ED arrival to imaging and to recombinant tissue plasminogen activator (rt-PA) treatment and compared these times to patients evaluated with CT alone.

Results

From January to October 2008, 95 patients had CTP and CTA studies in addition to NCCT for acute ischemic stroke. There were no differences between the average time to CT study or to rt-PA treatment between patients evaluated with multimodal CT imaging and patients assessed with NCCT alone.

Conclusions

Combining CTP and CTA with NCCT is feasible and does not adversely increase the time to CT imaging or rt-PA treatment in patients with acute ischemic stroke.  相似文献   
56.
Purified CD34+ Lin- Thy+ stem cells do not contain clonal myeloma cells   总被引:6,自引:0,他引:6  
High-dose therapy with autologous marrow or peripheral blood stem cell (PBSC) rescue has been extensively applied in the treatment of multiple myeloma (MM) patients during the past 10 years resulting in improved event-free and overall survival when compared with standard chemotherapy. However, relapses are common and cure is unlikely in the majority of patients. Because both bone marrow and PBSCs are contaminated with myeloma cells it is conceivable that relapse after autotransplantation originates at least in part from autografted tumor cells. In this study, mobilized PBSCs were examined for the presence of myeloma cells based on immunophenotyping and sensitive polymerase chain reaction (PCR)-based techniques. In addition, CD34+ Lin- Thy+ stem cells were purified from mobilized PBSC harvests of 10 MM patients by sequentially using counterflow elutriation centrifugation, treatment with phenylalanine methylester, and flow sorting, using 5-parameter gating (propidium iodide, forward scatter, side scatter, CD34+ v Lin- and CD34+ v Thy+). Virtually all mobilized unsorted PBSC preparations contained myeloma cells in sufficient quantities (range, < 0.01 to > 10%) potentially causing a disease relapse. Stem cell purification led to an overall enrichment by about 50-fold in all 10 patients; approximately 90% of the final cell population expressed CD34+ Lin- Thy+ with no evidence of myeloma cell contamination based on flow cytometric analysis of CD38bright cells (< 0.1%). Quantitative PCR amplification of patient-specific complementarity determining region III (CDRIII) DNA sequences showed depletion of clonal B cells by 2.7 to 7.3 logs, with the highest log reduction noted in the samples initially containing the most tumor cells. Our results show that purification of CD34+ Lin- Thy+ cells depletes myeloma cells to undetectable levels from up to 10% present in unsorted PBSCs, thus offering a tool to investigate whether MM relapse after autotransplantation can be reduced markedly.  相似文献   
57.
OBJECTIVE: The aim of this study was to test the effect of gut manipulation by either novel synbiotics or by metronidazole on either endotoxemia or the severity of liver damage in the course of acute pancreatitis from alcohol ingestion. METHODS: Sprague–Dawley rats were fed for 1 week through an intragastric tube a liquid diet with either: (i) 1 mL t.i.d. of a mixture of synbiotics (Lactobacillus acidophilus, Lactobacillus helveticus and Bifidobacterium in an enriched medium); (ii) 20 mg/kg t.i.d. metronidazole; or (iii) standard diet. Then, acute pancreatitis was induced by caerulein and when the disease was full‐blown, rats were fed an alcohol‐rich diet. Synbiotic and metronidazole treatment was given for a further 2 weeks. Transaminase and endotoxemia levels were measured before treatment, after 6 h, after 24 h and 2 weeks later, at the time the rats were killed. Liver samples were obtained for histological analysis. RESULTS: Synbiotics but not metronidazole improved the acute pancreatitis‐induced increase in endotoxemia and transaminase levels. The addition of alcohol worsened these variables to a limited extent in the synbiotic‐treated group, while metronidazole had a negative effect on liver damage. CONCLUSIONS: Gut flora pretreatment with synbiotics was able to effectively protect against endotoxin/bacterial translocation, as well as liver damage in the course of acute pancreatitis and concomitant heavy alcohol consumption. The beneficial effect of synbiotics on liver histology seems to be correlated with endotoxemia. Metronidazole did not produce such a beneficial effect; in fact, it further worsened liver damage when alcohol was added to the background of ongoing acute pancreatic inflammation.  相似文献   
58.
AP-1和肿瘤的关系研究进展   总被引:4,自引:0,他引:4  
转录因子AP-1(activatorprotein1),主要由Jun、Fos、ATF及JDP亚家族组成,亚家族单体以同源或异源二聚体的形式结合DNA靶序列,参与靶基因调节.对基因修饰小鼠和细胞的研究表明,AP-1参与细胞的正常生长和癌性转化过程,其在细胞中的作用取决于细胞类型、AP-1的组成和各组分的相对比例,也与刺激的种类密切相关.AP-1的活性受多种核因子调节,同时单体间也存在相互促进或拮抗作用.AP-1对各种刺激如应激、辐射或生长信号等作出生理或病理应答,参与细胞的增殖、分化和转化等过程,在肿瘤的形成、转移和侵袭中发挥重要作用,已经有学者研究通过抑制AP-1活性来发展抗肿瘤药物.  相似文献   
59.
Effect of freezing on the in vivo recovery of irradiated red cells   总被引:2,自引:0,他引:2  
BACKGROUND: Transfusion-associated graft-versus-host disease can be prevented by gamma radiation of blood components. The increased use of blood components donated for patients by their family members has resulted in an increased demand for the storage and handling of irradiated units, and the ability to freeze the cells would allow storage beyond their current expiration date. STUDY DESIGN AND METHODS: To assess the effect of freezing and deglycerolization on irradiated red cells, studies of autologous radiolabeled red cell recovery were performed using normal volunteers. Each unit of CPDA-1 red cells was immediately divided into two equal volumes. Further handling of each half was identical except that one was irradiated (3500 cGy). The units were grouped under three protocols: I, irradiated on Day 0 and frozen on Day 5 (n = 4); II, irradiated on Day 7, rejuvenated, and frozen on Day 14 (n = 5); and III, irradiated on Day 14, rejuvenated, and frozen on Day 18 (n = 3). All cells were frozen for 3 to 10 months at -80 degrees C. RESULTS: Irradiated and control units showed no significant differences in supernatant potassium or hemoglobin. Autologous 24-hour posttransfusion recoveries (mean +/− SD) for the three groups were: I, 89.7 +/− 5.6 percent (control, 90.6 +/− 3.2%); II, 85.3 +/− 5.7 percent (control, 83.7 +/− 3.0%); and III, 79.5 +/− 1.4 percent (control, 82.6 +/− 5.2%). CONCLUSION: Irradiated red cells can be frozen after being stored under various conditions and can still meet established guidelines requiring 75-percent recovery 24 hours after transfusion.  相似文献   
60.

Background  

Pneumocystis jiroveci pneumonia (PCP) is an important opportunistic infection among immunosuppressed patients, especially in those infected with human immunodeficiency virus (HIV). The clinical presentation of PCP in immunosuppressed patients have been well-reported in the literature. However, the clinical importance of PCP manifesting in the setting of an immunorestitution disease (IRD), defined as an acute symptomatic or paradoxical deterioration of a (presumably) preexisting infection, which is temporally related to the recovery of the immune system and is due to immunopathological damage associated with the reversal of immunosuppressive processes, has received relatively little attention until recently.  相似文献   
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