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61.
Summary Between 1955 and 1986, 25 children (aged 2 weeks to 15 years) were treated for intracranial ependymoma at M.D. Anderson Cancer Center. Nine patients had supratentorial primaries (5 high-grade, 4 low-grade), and 16 had infratentorial primaries (9 high-grade, 7 low-grade). Five patients had gross complete resection and 20 had incomplete resection. Seven patients received craniospinal irradiation (25–36 Gy to the neuroaxis, 45–55 Gy to tumor bed), 12 received local field irradiation (29–60 Gy, median 50 Gy). Five infants had adjuvant chemotherapy without radiotherapy, and 6 children had postradiotherapy adjuvant chemotherapy, and 12 patients had salvage chemotherapy with various agents and number of courses. Eight patients are alive, disease-free and without relapse from 1 year to 12 1/2 years from diagnosis (median 42 months). The primary failure pattern was local recurrence. The data suggest that 1) the long-term cure rate of children with ependymoma is suboptimal; 2) histologic grade may be of prognostic importance for supratentorial tumors; 3) prognosis appears worse for girls and infants under 3 years of age; 4) in well-staged patients routine spinal irradiation could be omitted; 5) the role of adjuvant chemotherapy is unclear. Address for offprints: Shiao Y. Woo, Department of Radiation Oncology, 6565 Fannin, M.S. DB1-37, Houston, Texas 77030, USA  相似文献   
62.
The surgical management in papillary thyroid cancer has been highly controversial. In the Department of Surgery (II), Kanazawa University Hospital, the surgical management especially for cervical lymph node metastases has changed since 1973 from a conservative approach to an aggressive one. In order to determine whether an aggressive approach is warranted, a retrospective multivariate analysis was carried out on 106 cases of papillary thyroid cancer. The patients have been followed for 10-28 years. Multivariate analysis was conducted following Cox's model. By this analysis, aggressive management appeared to have no impact on survival or relapse-free survival. However, age, sex, tumor size, and cervical lymphadenopathy were confirmed to be important prognostic factors in survival and/or relapse-free survival.  相似文献   
63.
Summary Prognostic factors define the study population, help formulate the study objectives, and influence the treatment strategies. They must be accounted for in the study analysis to obtain valid estimates of the treatment differences and to evaluate results across studies. The causal relationship between a prognostic factor and the study endpoint can only be established through prospective randomized study designs. Potential factors discovered through retrospective analysis must be verified to establish their validity. Using such factors prematurely to select patient population and treatment strategy for a new study will not establish the validity of the potentially important factor.Supported by NCI 5 PO1 CA53996-15 and NCI 5 U10 CA38926-08.  相似文献   
64.
Patients with stage T3N0~2M0 gastric carcinoma (n = 108) were studied for relevant prognostic factors. Peritoneal lavage cytology (PLC) was performed in all. In univariate analysis, 5-year survival rates were better with smaller serosal invasion (diameter <3.0 cm vs. ≥3.0 cm, 61% vs. 37%, P < 0.05) and fewer metastatic nodes (≤5 vs. ≥6, 57% vs. 29%, P < 0.05). In multivariate analyses, only these two factors were significant. The predictive value of PLC was not shown in both univariate and multivariate analyses. Peritoneal recurrence occured in 14 (22%) of 77 patients with negative PLC, and in 3 (18%) of 17 with positive PLC, the difference being not significant. Our results indicate that PLC is insensitive in predicting the development of peritoneal recurrence. Its role in the estimation of survival is limited, as many will die of visceral or locoregional recurrence if not of peritoneal dissemination.  相似文献   
65.
本研究分析影响慢性髓细胞白血病(CML)患者预后的危险因素。采用回顾性研究分析204例CML患者的临床及实验室检查资料,用Kaplan—Meier法绘制生存曲线,用Logrank检验比较生存率,运用Cox回归模型进行单因素及多因素分析,并分别计算Sokal,Hasford积分。结果表明:204例患者中位生存时间为50(32—65)月,5年生存率32.3%(95%CI,23.7%-42.6%)。干扰素组与羟基脲组的中位生存时间分别为56(41—67)月和41(19—56)月,5年生存率分别为45.4%(95%CI,37.5%-54.2%)和26.8%(95%CI,21.6%-33.3%)(P〈0.001)。经Cox回归分析,Ph染色体阴性、乳酸脱氢酶含量增高、外周血嗜碱性粒细胞≥10%、出现有核红细胞、骨髓原粒细胞≥4%、骨髓原始+早幼粒细胞≥10%和红细胞压积降低是CML预后不良的危险因素,而治疗方法也是影响CML预后的重要因素。羟基脲组经Sokal积分检验,高危组占72.9%,中危组占21.5%,而低危组占5.6%,中位生存时间分别为34(23—49)月、43(32—58)月、50(38—62)月;干扰素组经Hasford积分检验,高危组占17.6%,中危组占25.1%,低危组占57.3%,中位生存时间分别为44(33—57)月、56(45—70)月和66(52—76)月。结论:Ph染色体、乳酸脱氢酶含量、红细胞压积、外周血嗜碱性粒细胞、出现有核红细胞、骨髓原始和早幼粒细胞以及治疗方法是影响CML预后的重要因素。以Sokal积分系统评价羟基脲组患者不能很好区分危险组,而Hasford积分系统评价干扰素组患者,能够区分危险组。  相似文献   
66.
肛肠肌电图对盆底疾病的诊断价值(附360例报告)   总被引:2,自引:0,他引:2  
对3组患者均检查耻骨直肠肌,肛门内,外括约肌共1098块肉,共检测67880个运动单位电位。结果表明:便秘组肌电异常占82.2%(226/275),肿瘤术后组异常率为66.7%(14/24),脊髓病变组肌电异常率为98.4%(60/61),亦初步探讨肌电图对盆底疾病的诊断价值。  相似文献   
67.
Magnetic susceptibility, as a physical property of materials, plays important roles in many physical, chemical, engineering, and medical applications. Its quantification becomes of significant interest when MRI becomes a commonly used technique in biomedical applications. A general method is presented here for quantifying arbitrary magnetic susceptibility distributions in a localized region on the basis of first principles of magnetic induction field distributions in space. A proof of the concept was demonstrated by computer simulations. The study establishes the methodological basis for quantitative magnetic susceptibility imaging with MR.  相似文献   
68.
造影剂到达腹主动脉的峰值大小与患者因素的关系   总被引:3,自引:0,他引:3  
目的探讨造影剂到达腹主动脉的峰值大小与患者因素之间的关系。方法108例患者以2.5ml/s注射欧乃派克(300mgI/ml)20ml,12s后采用testbolus技术在腹腔干水平同层动态扫描腹主动脉,用dynamic evaluation软件测得腹主动脉的峰值大小,采用单因素回归分析和多因素逐步回归分析法研究患者的性别、年龄、身高、体重、心率、血压、注射位点、达峰时间及是否有心脏病、糖尿病、或化疗史对造影剂到达腹主动脉峰值大小是否有影响及影响程度。结果造影剂到达腹主动脉峰值大小,在男性平均比女性低;其随年龄、身高、体重、达峰时间的增加而逐渐降低,注射位点在手背静脉其值平均比在肘部静脉低;其不受心率、血压、是否有心脏病、糖尿病或化疗史的影响。参考公式:峰值大小(HU)=383.8400-身高(cm)×1.0909-体重(kg)×0.6760 注射位点×16.7878-达峰时间(s)×1.6882。结论可根据患者的性别、年龄、身高、体重、注射位点和达峰时间来适当调整患者CT血管成像时造影剂用量。  相似文献   
69.
Garcinia gardneriana (Planch. & Triana) Zappi (Clusiaceae) is widely distributed in Brazil and used in folk medicine to treat inflammation, pain, and urinary tract and other infections. However, very few studies have analyzed these therapeutic effects. In this study, the anti-inflammatory effects of the hydroalcoholic extracts from Garcinia gardneriana (HEGG) and some of its isolated biflavonoids were evaluated. The results showed that HEGG from the leaves, bark and seeds reduced carrageenan-induced mouse paw inflammation, in addition to diminishing the myeloperoxidase activity in the stimulated tissues. The reduction of neutrophil infiltration by treatment with the HEGG from leaves was confirmed by histology. The leaf extract also reduced the paw oedema evoked by bradykinin, histamine, prostaglandin E2 and 12-O-tetradecanoylphorbol acetate. However, it partially decreased substance P and compound 48/80-caused paw oedema, without any influence on the arachidonic acid-induced oedema. Both of the isolated compounds, fukugetin and GB-2a, prevented the carrageenan-induced paw oedema. In conclusion, this study showed important anti-inflammatory effects of HEGG through its interaction with different intracellular signaling pathways, without interfering with the formation of arachidonic acid (AA) metabolites. These characteristics, in addition to the wide distribution and culturing ease of the plant, confirm its popular use and highlight its promise in the development of new anti-inflammatory drugs.  相似文献   
70.
AIM: As the practice of multiple assessments of glucose concentration throughout the day increases for people with diabetes, there is a need for an assessment of glycaemic control weighted for the clinical risks of both hypoglycaemia and hyperglycaemia. METHODS: We have developed a methodology to report the degree of risk which a glycaemic profile represents. Fifty diabetes professionals assigned risk values to a range of 40 blood glucose concentrations. Their responses were summarised and a generic function of glycaemic risk was derived. This function was applied to patient glucose profiles to generate an integrated risk score termed the Glycaemic Risk Assessment Diabetes Equation (GRADE). The GRADE score was then reported by use of the mean value and the relative percent contribution to the weighted risk score from the hypoglycaemic, euglycaemic, hyperglycaemic range, respectively, e.g. GRADE (hypoglycaemia%, euglycaemia%, hyperglycaemia%). RESULTS: The GRADE scores of indicative glucose profiles were as follows: continuous glucose monitoring profile non-diabetic subjects GRADE = 1.1, Type 1 diabetes continuous glucose monitoring GRADE = 8.09 (20%, 8%, 72%), Type 2 diabetes home blood glucose monitoring GRADE = 9.97 (2%, 7%, 91%). CONCLUSIONS: The GRADE score of a glucose profile summarises the degree of risk associated with a glucose profile. Values < 5 correspond to euglycaemia. The GRADE score is simple to generate from any blood glucose profile and can be used as an adjunct to HbA1c to report the degree of risk associated with glycaemic variability.  相似文献   
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