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51.
Low dose preoperative radiotherapy for carcinoma of the oesophagus: results of a randomized clinical trial. 总被引:9,自引:0,他引:9
S J Arnott W Duncan G R Kerr P R Walbaum E Cameron W J Jack W J Mackillop 《Radiotherapy and oncology》1992,24(2):108-113
One-hundred-and-seventy-six patients with potentially operable squamous cell carcinoma or adenocarcinoma of the middle or lower thirds of the oesophagus were randomly assigned to preoperative radiotherapy or surgery alone. Patients assigned to the radiotherapy arm received 20 Gy in 10 treatments over 2 weeks, using parallel opposed 4 MV beams. The preoperative radiotherapy was not associated with any significant acute morbidity or any increase in operative complications. The median survival of the overall group of 176 patients was 8 months, and the 5-year survival was 13%. There was no significant difference in the survival of the 90 patients who received preoperative radiotherapy and the 86 who were managed by surgery alone. Proportional hazards analysis identified lymph node involvement, high tumour grade and male sex as significant adverse prognostic features, but the treatment option assigned had no prognostic significance. It was concluded that low dose preoperative radiotherapy offered no advantage over surgery alone. 相似文献
52.
A modified end-point enzymatic method for the measurement of ammonia in stool water is presented. A protein precipitation step was included in order to inactivate urease and faecal enzymes, which oxidise NADH. The modified method is reliable, with acceptable precision and accuracy, and is linear up to a concentration of 1.5 mmol/l. 相似文献
53.
ANGIOTENSIN CONVERTING ENZYME (ACE) INHIBITORS AND KININ METABOLISM: EVIDENCE THAT ACE INHIBITORS MAY INHIBIT A KININASE OTHER THAN ACE 总被引:1,自引:0,他引:1
Duncan J. Campbell 《Clinical and experimental pharmacology & physiology》1995,22(12):903-911
1. Angiotensin converting enzyme (ACE) converts angiotensin I to angiotensin II, and also metabolizes bradykinin-(1–9) to bradykinin-(1–7) and bradykinin-(1–7) to bradykinin-(1–5). Increases in endogenous kinin levels may contribute to the therapeutic effects of ACE inhibitors. 2. ACE inhibitors increase vascular levels of both bradykinin-(1–9) and its ACE cleavage product bradykinin-(1–7), at doses below the threshold for ACE inhibition, leading to the proposal that ACE inhibitors may also inhibit a non-ACE kininase which cleaves both kinin peptides; this non-ACE kininase may be the major pathway of kinin metabolism in the vasculature and some other tissues. 3. In support of this proposal, ACE inhibitors potentiate bradykinin-(1–9) effects at doses which have little or no effect on ACE activity, as indicated by angiotensin I conversion to angiotensin II. ACE inhibitors also potentiate the actions of ACE-resistant kinin analogues, which may be susceptible to metabolism by a non-ACE kininase. 4. Identification and characterization of the putative non-ACE kininase which is inhibited by ACE inhibitors may reveal novel approaches to the tissue-specific modulation of kinin levels. 相似文献
54.
M R Duncan T J Wilson J Van De Water B Berman R Boyd G Wick M E Gershwin 《Journal of autoimmunity》1992,5(5):603-615
University of California, Davis, line 200 and 206 chickens spontaneously develop an autoimmune syndrome that has many features analogous to human scleroderma, including dermal fibrosis, antinuclear antibodies and antibodies to type II collagen. These birds also have thymic subcapsular epithelial defects and an abnormality in T cell calcium influx and proliferation in response to both T cell receptor-dependent and -independent activators. To determine whether fibroblast activation is a contributing factor to development of skin fibrosis in line 200/206 chickens, as it is in human scleroderma, we studied the collagen, non-collagenous protein and glycosaminoglycan (GAG) production of 34 separate fibroblast lines derived from the normal and fibrotic skin of line 200 and 206 chickens and from the skin of control chicken lines 058 and 254. The mean +/- SEM 24-h incorporation of 3H-proline or 3H-glucosamine into extracellular collagen, non-collagenous protein or GAG by first passage fibroblast lines derived from the fibrotic skin of diseased birds was 1,526 +/- 136, 859 +/- 82 and 25.7 +/- 1.3 dpm/10(3) cells, respectively, while fibroblast lines derived from the skin of control birds produced only 341 +/- 36, 343 +/- 42 and 15.2 +/- 1.4 dpm/10(3) cells. Similar differences in results were recorded for cell-associated production, and when collagen and non-collagenous protein production were assessed using non-radioactive electrophoretic methods. The activated phenotype of the fibroblast lines derived from the fibrotic skin of diseased birds persisted through 10 cell doublings in tissue culture. However, the ratio of type I:III collagen and the profile of GAG types produced were similar in all fibroblast lines studied. These results suggest that fibroblast activation is responsible for the skin fibrosis observed in this avian model of scleroderma. 相似文献
55.
目的:本研究旨在探讨多巴酚丁胺对缺血性心肌病(ICM)患者左心室(LV)充盈功能的影响,并确定峰值负荷时限制性充盈型(RFP)是否具有预后预测价值。背景:ICM患者峰值负荷时RFP的预后价值尚属未知。方法:在静息和负荷情况下,采用多普勒超声心动检查研究了69例ICM患者;RFP定义为跨二尖瓣E/A比≥1.0、等容舒张时间(IVRT)〈80ms及E波减速时间(EDT)〈120ms。结果:69例患者中有42例静息时出现RFP,其中有24例患者负荷情况下转变为非RFP(EA),18例患者RFP持续存在(EE);69例患者中27例静息和峰值负荷时均无RFP(AA)。 相似文献
56.
57.
Most patients who survive a stroke experience some degree of physical recovery. Selecting the appropriate outcome measure
to assess physical recovery is a difficult task, given the heterogeneity of stroke etiology, symptoms, severity, and even
recovery itself. Despite these complexities, a number of strategies can facilitate the selection of functional outcome measures
in stroke clinical trial research and practice. Clinical relevance in stroke outcome measures can be optimized by incorporating
a framework of health and disability, such as the International Classification of Functioning, Disability, and Health (ICF).
The ICF provides the conceptual basis for measurement and policy formulations for disability and health assessment. All outcome
measures selected should also have sound psychometric properties. The essential psychometric properties are reliability, validity,
responsiveness, sensibility, and established minimal clinically important difference. It is also important to establish the
purpose of the measurement (discriminative, predictive, or evaluative) and to determine whether the purpose of the study is
to evaluate the efficacy or effectiveness of an intervention. In addition, when selecting outcome measures and time of assessment,
the natural history of stroke and stroke severity must be regarded. Finally, methods for acquiring data must also be considered.
We present a comprehensive overview of the issues in selecting stroke outcome measures and characterize existing measures
relative to these issues. 相似文献
58.
59.
E J Maher L Coia G Duncan P A Lawton 《International journal of radiation oncology, biology, physics》1992,23(1):239-244
Six-hundred and forty four radiation therapists from 21 European countries, Canada, and the USA responded to a questionnaire regarding the management of three cases of advanced cancer. The cases were a 64-year-old man with brain metastases from small cell carcinoma of the lung; a 64-year-old woman with bone metastases from carcinoma of the breast and a 59-year-old man with squamous cell carcinoma of the bronchus and mediastinal nodes. There was variation as to the perceived prognosis and appropriate aims of therapy, particularly for the case of squamous cell carcinoma of the bronchus. The total dose and number of fractions could be related to the perceived aims and expectations of treatment, for example, those aiming to extend life gave higher doses of radiotherapy and those aiming only to relieve symptoms gave lower. Similarly, those describing treatment as radical and estimating longer survival gave higher doses and more fractions than those treating palliatively. Variations in the role of the radiation oncologist in the management of advanced and metastatic cancer in the USA, Canada and Europe are discussed. 相似文献
60.