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11.
12.
A postal survey of 100 hospitals throughout the United Kingdom and Ireland was conducted to assess current practice in the pre-operative assessment and use of pulmonary artery catheters in patients undergoing elective abdominal aortic aneurysm repair. Seventy-four completed questionnaires were received. The survey revealed that 53% of respondents hold designated pre-operative assessment clinics, attended by anaesthetists in 54% and cardiologists in 26%. However, only 4% of respondents have a written protocol for stratifying patients and assessing peri-operative risk. By far the commonest investigation of choice for further cardiological assessment is transthoracic echocardiography (67%). Other investigations of choice are multiple update gated acquisition (MUGA) scan (13%), dipyridamole thallium imaging (9%), exercise ECG (6%), stress echocardiography (1%) and stress MUGA (1%). Two units (3%) never undertook further investigation. Pulmonary artery flotation catheters are used as a routine by 9% of respondents, dependent upon left ventricular ejection fraction by 65%, dependent on other factors by 7% and not used at all by 19%. The survey reveals widespread variation in pre-operative assessment of patients undergoing elective repair of abdominal aortic aneurysm.  相似文献   
13.
We assessed the feasibility and psychometric properties of two commonly used health status questionnaires in Parkinson's disease (PD): the generic Nottingham Health Profile (NHP) and the disease-specific 39-item Parkinson's disease Questionnaire (PDQ-39), from a cross-sectional postal survey of PD patients (N = 81), using traditional and Rasch measurement methodologies. Overall response rate was 88%. Both questionnaires were found feasible, although the NHP performed less well. The PDQ-39 had fewer floor effects and was better able to separate respondents into distinct groups than the NHP, whereas the latter exhibited less ambiguous dimensionality and better targeting of respondents with non-extreme scores. Reliability and validity indices were similar, and potential differential item functioning by age and gender groups was found for both questionnaires. PDQ-39 response alternatives indicated ambiguity. With few exceptions, questionnaire scales were unable to meet recommended standards fully. While preliminary, this study illustrates the need for thorough evaluation of outcome measures and has implications beyond the questionnaires used here. Although promising, both questionnaires warrant further developmental work and stronger support of measurement validity before they could be considered fully suitable for valid use in PD, in particular in earlier stages of the disease.  相似文献   
14.
<正> 花粉在古代就曾作为强身保健食品。美、英两国的科学家曾分析了花粉的成分,发现花粉由96种元素组成,其中有维生素、矿物质、酶、蛋白质和某些其它物质。美国明尼苏达大学曾做过花粉对动物的增重实验。当41~150日龄小猪饲料中添加2~3%的玉米花粉时,体重增长明显快于对照组,  相似文献   
15.
Summary: Some of the properties of 4–bromobenzalde-hyde semicarbazone (compound IV), a prototype molecule of a new class of anticonvulsants, aryl semicarbazones, are described. Compound IV demonstrated activity in the maximal electroshock (MES) and subcutaneous pentylenetetrazol (scPTZ) tests in mice, with low neurotoxicity. When given orally to rats, it displayed high potency in the MES test and very low neurotoxicity, resulting in a high protective index (PI). Compound IV displayed no proconvulsant properties, and development of rapid tolerance was not noted. When administered intraperitoneally (i.p.) at doses of 100, 300, or 600 mg/kg to rats, compound IV had no effect on levels of γ-aminobu-tyric acid (GABA) or on GABA-T activity in whole brain. When tested in vitro, compound IV had no effect on rat brain GABA-T at a drug concentration of 100 μM. Although the activities of certain drug-metabolizing enzymes were increased after oral administration of compound IV to rats, these effects were less prominent than those of phenytoin (PHT) and carbamazepine (CBZ). The principal mode of action of compound IV does not appear to be an interaction with the GABAA receptor complex, and other mechanisms, involving excitatory amino acid neurotransmission, will have to be considered in future investigations of the anticonvulsant activity of this compound.  相似文献   
16.
The present trial was designed to evaluate clinical scores (single observer) of sodium lauryl sulphate (SLS)-induced skin irritation in a group of subjects (n = 10) over a 10-day period along with various skin function parameters. In order to avoid significant variations due to secondary phenomena, the following parameters were recorded with non-invasive instruments in this order: skin capacitance (C1; arbitrary units; CM420 Corneometer), transepidermal water loss (TEWL; g/m2.h; Evaporimeter) and laser Doppler flowmetry (CBFV: cutaneous blood flow values; Periflux). All examinations were performed during winter on reclined relaxed subjects present for at least 10 min in a test room with controlled temperature and relative humidity (t degrees: 19.5-20.7 degrees C and RH: 47.3-60.3%). The analysis of differential data (delta = value at tx-value before test; 2-way ANOVA) was made on single parameters as a function of site (volar forearm versus neck) and time (from 24 h after 48-h occlusion with 5% SLS up to 10 days later). The profile of erythema scores over time differed between neck and forearm, but the delta CBFV readings with the laser Doppler instrument did not detect significant site-time interactions. Roughness (blind evaluation with palpating finger) and capacitance readings (delta C1) showed significant differences between sites, but the profile over time was similar in both locations. delta TEWL did not differ according to anatomical location. The reason for different erythema scores on neck and forearm might be related to inherent regional variation of optical properties of the skin or to a substantial contribution of SLS-induced roughness to the readings of erythema.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
17.
本文对肺部三种疾病1536例患者的病历资料,按病种作了统计归类。运用模糊数学原理建立了征候一疾病间的模糊关系矩阵,用参量加权模糊综合评判模型,对肺部三种疾病鉴别诊断的符合率达82.91%以上,因此认为文中建立的模型,对肺部三种疾病鉴别诊断具有参考价值。  相似文献   
18.
Safety evaluation of surgical materials by cytotoxicity testing   总被引:2,自引:1,他引:1  
The cytotoxicity of three kinds of commercially available absorbable hemostats [oxidized cellulose (Surgicel, gauze and cotton types), microfibrillar collagen (Avitene), and cotton-type collagen (Integran)] and one adhesion barrier [sodium hyaluronate and carboxymethyl-cellulose membrane (Seprafilm)] were comparatively assessed by a colony assay using V79 cells and a minimum essential medium (MEM) elution assay in combination with a neutral red assay using L929 cells. Strong cytotoxicity was detected for Surgicel by both the MEM elution assay and the colony assay. For Avitene, both methods revealed weak cytotoxicity. For Seprafilm, no cytotoxicity was detected by the MEM elution assay, while a moderate degree of cytotoxicity was observed in the colony assay. For Integran cytotoxicity was not detected by either the MEM elution or the colony assay. The results of the different methods showed some inconsistency in terms of the degree of cytotoxicity of the materials. It is proposed that the combination of two or more sensitive cytotoxicity testing methods for the evaluation of biomaterials is necessary to avoid false-negative results for biomaterials at the preclinical stage. Furthermore, investigation of the correlation between the cytotoxicity and the extraction period of the surgical materials is helpful for predicting the effect of prolonged in vivo use of biomaterials on surrounding cells, tissues, and organs.  相似文献   
19.
In this work, the dosimetric characteristics of a new commercial carbon fiber treatment table are investigated. The photon beam attenuation properties of the Siemens image-guided radiation therapy (IGRT) tabletop were studied in detail. Two sets of dosimetric measurements were performed. In the first experiment a polystyrene slab phantom was used: the central axis attenuation and the skin-sparing detriment were investigated. In the second experiment, the off-axis treatment table transmission was investigated using a polystyrene cylindrical phantom. Measurements were taken at the isocenter for a 360° rotation of the radiation beam. Our results show that the photon beam attenuation of the Siemens IGRT carbon fiber tabletop varies from a minimum of 2.1% (central axis) to a maximum of 4.6% (120° and 240° beam incidence). The beam entrance dose increases from 82% to 97% of the dose at the depth of maximum for a clinical 6-MV radiation field. The depth of maximum also decreases by 0.4 cm. Despite the wedge cross section of the table the beam attenuation properties of the IGRT tabletop remain constant along the longitudinal direction. American Association of Medical Dosimetrists.  相似文献   
20.
A literature search was conducted to identify 'nursing led in-patient units' where the nurse is the designated leader of the clinical team. The review concentrates on studies which have attempted to measure the impact of nursing-led in-patient units and reviews both the methodology and outcomes. Three major bodies of work were identified. Lydia Hall's evaluation of the Loeb Center for Nursing and Rehabilitation (USA) is reviewed in some detail. This work was the model for 'nursing beds' at the two Oxfordshire Nursing Development Units (UK) in the 1980s. Studies evaluating these centres are reviewed and reports of similar UK units discussed. A third body of work evaluates a nurse-managed critical care environment. Common features include a case mix based on nursing need with nurses having authority to admit and discharge patients. While results are generally favourable, with improved patient independence, fewer readmissions, lower mortality and cost savings reported in some or all of the studies, all studies reviewed demonstrate the difficulties of applying an experimental model to real life clinical services. Methodological limitations render firm conclusions difficult. Techniques adopted from studies in field settings, the so-called 'quasi-experiment', are advocated as a remedy, as is further study of the process of care in investigating this model of care delivery.  相似文献   
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