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101.
Akmal Safwat S?ren M Bentzen Ingela Turesson Jolyon H Hendry 《International journal of radiation oncology, biology, physics》2002,52(1):198-204
BACKGROUND: The large patient-to-patient variability in the grade of normal tissue injury after a standard course of radiotherapy is well established clinically. A better understanding of this individual variation may provide valuable insights into the pathogenesis of radiation damage and the prospects of predicting the outcome. PURPOSE: To estimate the relative importance of the stochastic vs. patient-related components of variability in the expression of radiation-induced normal tissue damage. METHODS AND MATERIALS: The study data were selected from the dose fractionation studies of Turesson in Gothenburg. Patients treated with bilateral internal mammary fields, who completed at least 10 years of follow-up, were included. The material included 22 different fractionation schedules (11 on each side). Telangiectasia was graded on an arbitrary 6-point scale using clinical photographs of the irradiated fields. For each field, in each patient, a curve showing the grade of telangiectasia as a function of time was constructed. A measure of radioresponsiveness was obtained from the difference between the area under the curve (AUC) for a specific field in an individual patient minus the mean AUC of fields receiving the same dose fractionation schedule. As a confirmatory procedure, the same analysis was repeated with a weighted area under the curve (WAUC) approach, in which the time spent at or above each of the 5 nonzero grades was calculated for each field in each patient. These times were used as explanatory variables in a linear regression analysis of biological equivalent dose to establish statistically the weight of each grade providing the optimal relationship between dose and effect. Using these regression coefficients, the weighted area under the grade-time curve (WAUC) was estimated. RESULTS: The AUC was significantly correlated with the isoeffective dose in 2-Gy fractions (ID2). An analysis of variance components, using the maximum likelihood method, showed that 90% (with 95% confidence limits 65% and 100%) of the variance in radioresponsiveness in the right-sided field was explained by the radioresponsiveness on the left-sided field. Through the linear regression analysis between the AUC and the ID2, it was estimated that patients with a reaction that is 1 SD from the population mean would require a dose modification of approximately 23 Gy (from the group mean of 56 Gy) to give them a level of reaction similar to the group average. Similarly, the WAUC was significantly correlated with the ID2, and 81% (with 95% confidence limits 49% and 100%) of the variance in radioresponsiveness in the right-sided field was explained by the radioresponsiveness on the left-sided field. Patients with a reaction that is 1 SD from the population mean would require a dose modification of approximately 21 Gy (from the group mean of 56 Gy) to give them a level of reaction similar to the group average. CONCLUSION: For a given fractionation schedule, patient-related factors explain 81-90% of the patient-to-patient variation in telangiectasia level seen after radiotherapy. The remaining 10-19% are explained by stochastic effects. This observation encourages further research into genetic or phenotypic assays of normal tissue radioresponsiveness. 相似文献
102.
Serum parathyroid hormone (PTH) levels have been measured in 8 patients with hypercalcaemia associated with urological malignancy: 3 renal cell carcinomas, 2 adenocarcinomas of prostate, 2 transitional cell carcinomas of bladder and one transitional cell carcinoma of kidney. Five (63%) of these 8 patients had bone metastases. PTH was detectable in the serum of all 8 hypercalcaemic patients, but in only 2 cases was the PTH level above the normal range, and in one of these a coincidental parathyroid adenoma was found to be responsible for the hypercalcaemia. It appears that these tumours can produce a hormone-like substance with biological effects similar to PTH. 相似文献
103.
The sensitivity of stromal progenitor cells (CFU-F) in mouse marrow to whole-body 60Co gamma-irradiation delivered at 0.65 Gy per day, was characterised by a D0 value of about 2.5 Gy up to an accumulated dose of 5 Gy. The cells were less sensitive to higher doses. The rate of recovery following irradiation for 14 days (9.1 Gy) was less than the rate after 30 days irradiation (19.5 Gy). The latter rate of recovery approached that of the stem cells (CFU-S). At 9-10 months after either dose of irradiation, recovery of both CFU-F and CFU-S was incomplete at 30-70% of the aged control. 相似文献
104.
Seven cases of neonatal pulmonary sequestration are reviewed which illustrate the varied clinical presentations and radiological findings. In four patients, real time ultrasound scanning was used to image the chest and the features are described. In three cases, the systemic supplying artery was demonstrated by duplex Doppler scanning and further invasive investigations were avoided; after a chest radiograph, this should be the examination of choice in the investigation of a neonate with a possible pulmonary sequestration. 相似文献
105.
医用聚乳酸类高分子材料的应用 总被引:1,自引:4,他引:1
目的:阐述医用聚乳酸类高分子材料的需求,综述聚乳酸类高分子材料在生物医学领域的应用,并对其在医学领域的应用前景进行展望。资料来源:应用计算机检索ACS美国化学学会数据库2000-01/2006-12关于医用聚乳酸类高分子材料的文章,检索词“polylactide”;利用Elsevier Science全文电子期刊数据库2000-01/2006-12进行检索,检索词“polylactide”和全文检索“Medical polymeric material”。同时利用计算机检索中国期刊全文数据库1994-01/2005-12的相关文章,限定文章语言种类为中文,检索词“聚乳酸类医用高分子材料”。资料选择:对资料进行初审,纳入标准:①关于聚乳酸类医用高分子材料的需求。②医用聚乳酸类高分子材料的合成及应用。排除标准:重复性研究。资料提炼:共收集到符合上述要求的文献100篇,排除70篇重复性研究。30篇符合纳入标准:其中6篇关于聚乳酸类医用高分子材料的需求,24篇关于医用聚乳酸类高分子材料的合成及应用。资料综合:聚乳酸是一种具有良好的生物相容性和可生物降解的聚合物,最终的降解产物是二氧化碳和水,对人体无毒、无刺激。目前,聚乳酸类材料产品在医学领域广泛用于药物控制释放载体、组织工程、骨内固定、修复、手术缝合线、人造皮肤以及三维多孔支架等。结论:医用聚乳酸类高分子材料有非常广阔的应用前景,今后研究的重点是研发高效低成本的聚乳酸制备方法,合成适应于不同医疗或其他用途的、具有优良生物相容性的聚乳酸共聚物高分子材料。 相似文献
106.
健胃愈疡颗粒干预下大鼠胃溃疡黏膜乳癌相关肽和血小板活化因子的表达及与胃黏膜疏水性的相关性研究 总被引:1,自引:0,他引:1
目的:观察对胃溃疡复发有较好疗效的健胃愈疡颗粒对溃疡黏膜乳腺癌相关肽和血小板活化因子表达的影响,分析其可能的作用机制。方法:实验于2005-07/2006-07在湘雅医院中心实验室完成。SD大鼠110只,雌雄各半,随机抽签法分为5组,即正常对照组、假手术组、雷尼替丁组、健胃愈疡组,各20只;模型组30只。以Okabe改良法复制大鼠实验性胃溃疡,假手术组仅以生理盐水代替乙酸注入玻管内。造模后24h,雷尼替丁组、健胃愈疡组大鼠分别灌服盐酸雷尼替丁和健胃愈疡颗粒(药物组成为:柴胡、党参、白芍、延胡索、白芨、珍珠层粉、青黛、甘草,湖南湘雅制药有限公司生产)药液10mL/kg,分别相当于2.70,1.62g/kg,1次/d。假手术组、模型组灌服蒸馏水10mL/kg。10d后各组中随机取出10只大鼠剖腹取胃(处死前大鼠禁食24h),90d时将模型组20只大鼠再分为模型复发组和模型非复发组,各10只;除正常对照组、假手术组、模型非复发组大鼠腹腔内注射生理盐水外,其余各组大鼠腹腔内注射白细胞介素1,1μg/kg;在注射48h,大鼠禁食24h后,剖腹取胃。观察其对胃溃疡大鼠胃黏膜氨基己糖及磷脂含量、溃疡指数和胃黏膜血流的影响,并用RT-PCR观察乳癌相关肽乳癌相关肽和血小板活化因子表达的变化。结果:实验动物110只,全部进入结果分析。①模型组10,92d胃黏膜血流均低于正常对照组(P<0.01);健胃愈疡组同期胃黏膜血流均高于模型组(P<0.01)。②健胃愈疡组和雷尼替丁组10d溃疡指数均低于模型组(P<0.01,P<0.05);模型复发组、健胃愈疡组和雷尼替丁组92d溃疡指数均高于模型组(P<0.01);健胃愈疡组10,92d溃疡指数及复发率均低于雷尼替丁组(P<0.05,P<0.01)。③模型组10,92d氨基己糖和磷脂含量均低于正常对照组(P<0.01)。健胃愈疡组10,92d氨基己糖和磷脂含量均高于模型组和雷尼替丁组(P<0.01)。溃疡指数与氨基已糖、磷脂含量呈负相关(r=-0.957,-0.960,P<0.01)。④健胃愈疡组和雷尼替丁组10d乳癌相关肽mRNA表达较正常组和假手术组提高,血小板活化因子mRNA的表达下调(P<0.01),健胃愈疡组两指标表达变化较雷尼替丁组显著(P<0.01);模型复发组、健胃愈疡组和雷尼替丁组92d乳癌相关肽mRNA、血小板活化因子mRNA的表达同组10d比较差异无显著性意义(P>0.05);模型组乳癌相关肽mRNA、血小板活化因子mRNA的表达同组10d比较差异有显著性意义(P<0.01)。结论:健胃愈疡颗粒可提高乳癌相关肽mRNA及下调血小板活化因子mRNA的表达,影响胃黏膜氨基己糖及磷脂含量,可能是其促进溃疡愈合的机制之一。 相似文献
107.
体外膜肺氧合技术支持治疗期间患者血乳酸浓度及其预后 总被引:2,自引:1,他引:2
目的:探讨体外膜肺氧合支持治疗患者血乳酸浓度的变化和预后。方法:于2004-12/2006-09在中国医学科学院阜外心血管病医院因脱离体外循环困难的心脏外科术后患者、扩张性心肌病和冠状动脉粥样硬化性心脏病发生心源性休克的患者共40例进行了体外膜肺氧合支持治疗,按年龄和存活预后分为4组:成人存活组、成人死亡组、儿童存活组、儿童死亡组。分析4组的治疗效果,分别抽取各组患者体外膜肺氧合建立时、体外膜肺氧合运转6h、运转中间时点、停机前6h、停机时的血乳酸浓度。结果:①体外膜肺氧合支持治疗患者40例,成人组26例,20例脱机,16例生存,10例死亡,脱机率76.9%,生存率61.5%;儿童组14例,7例脱机,5例生存,9例死亡,脱机率50.0%,生存率35.0%。②成人或儿童存活组的乳酸浓度都与死亡组有明显差别,存活组血乳酸浓度明显低于死亡组,其中建立和运转6h、中间时点的差异有显著性意义(P<0.05),其余2个时点的差异有非常显著性意义(P<0.001)。组内与建立时比较,中间时点、停止前6h、停止时差异均有显著性意义(P<0.001),血乳酸浓度逐渐降低。结论:经体外膜肺氧合支持治疗的患者,血乳酸浓度明显下降,脱机时血乳酸仍高的患者预后不良。 相似文献
108.
109.
Gordon J. Hendry Linda Fenocchi Jim Woodburn Martijn Steultjens 《Journal of foot and ankle research》2018,11(1):48
Background
Foot pain is common amongst the general population and impacts negatively on physical function and quality of life. Associations between personal health characteristics, lifestyle/behaviour factors and foot pain have been studied; however, the role of wider determinants of health on foot pain have received relatively little attention. Objectives of this study are i) to describe foot pain and foot health characteristics in an educated population of adults; ii) to explore associations between moderate-to-severe foot pain and a variety of factors including gender, age, medical conditions/co-morbidity/multi-morbidity, key indicators of general health, foot pathologies, and social determinants of health; and iii) to evaluate associations between moderate-to-severe foot pain and foot function, foot health and health-related quality-of-life.Methods
Between February and March 2018, Glasgow Caledonian University Alumni with a working email address were invited to participate in the cross-sectional electronic survey (anonymously) by email via the Glasgow Caledonian University Alumni Office. The survey was constructed using the REDCap secure web online survey application and sought information on presence/absence of moderate-to-severe foot pain, patient characteristics (age, body mass index, socioeconomic status, occupation class, comorbidities, and foot pathologies). Prevalence data were expressed as absolute frequencies and percentages. Multivariate logistic and linear regressions were undertaken to identify associations 1) between independent variables and moderate-to-severe foot pain, and 2) between moderate-to-severe foot pain and foot function, foot health and health-related quality of life.Results
Of 50,228 invitations distributed, there were 7707 unique views and 593 valid completions (median age [inter-quartile range] 42 [31–52], 67.3% female) of the survey (7.7% response rate). The sample was comprised predominantly of white Scottish/British (89.4%) working age adults (95%), the majority of whom were overweight or obese (57.9%), and in either full-time or part-time employment (82.5%) as professionals (72.5%). Over two-thirds (68.5%) of the sample were classified in the highest 6 deciles (most affluent) of social deprivation. Moderate-to-severe foot pain affected 236/593 respondents (39.8%). High body mass index, presence of bunions, back pain, rheumatoid arthritis, hip pain and lower occupation class were included in the final multivariate model and all were significantly and independently associated with moderate-to-severe foot pain (p?<?0.05), except for rheumatoid arthritis (p?=?0.057). Moderate-to-severe foot pain was significantly and independently associated lower foot function, foot health and health-related quality of life scores following adjustment for age, gender and body mass index (p?<?0.05).Conclusions
Moderate-to-severe foot pain was highly prevalent in a university-educated population and was independently associated with female gender, high body mass index, bunions, back pain, hip pain and lower occupational class. Presence of moderate-to-severe foot pain was associated with worse scores for foot function, foot health and health-related quality-of-life. Education attainment does not appear to be protective against moderate-to-severe foot pain.110.