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71.
PURPOSE: The practice patterns of medical oncologists at a large National Cancer Institute Comprehensive Cancer Center in Detroit, MI were evaluated to better understand factors associated with accrual to breast cancer clinical trials. PATIENTS AND METHODS: From 1996 to 1997, physicians completed surveys on 319 of 344 newly evaluated female breast cancer patients. The 19-item survey included clinical data, whether patients were offered clinical trial (CT) participation and enrollment, and when applicable, reasons why they were not. Multivariate analyses using logistic regression were performed to evaluate predictors of an offer and enrollment. RESULTS: The patients were 57% white, 32% black, and 11% other/unknown race. One hundred six (33%) were offered participation and 36 (34%) were enrolled. In multivariate analysis, CTs were less likely offered to older women (mean age, 52 years for those offered v 57 years for those not offered; P =.0005) and black women (21% of blacks offered v 42% of whites; P =.0009). Women with stage 1 disease, poor performance status, and those who were previously diagnosed were also less likely to be offered trials. None of these factors were significant predictors of enrollment. Women were not offered trials because of ineligibility (57%), lack of available trials (41%), and noncompliance (2%). Reasons for failed enrollment included patient refusal (88%) and failed eligibility (12%). CONCLUSION: It is important for cooperative groups to design studies that will accommodate a broader spectrum of patients. Further work is needed to assess ways to improve communication about breast cancer CT participation to all eligible women.  相似文献   
72.
增殖细胞核抗原在鼻咽癌中表达的定量研究   总被引:10,自引:1,他引:10  
为了增加鼻咽癌的诊断和预后判定指标,应用抗增殖细胞核抗原(PCNA)单克隆抗体,采用免疫组化染色LAS-SP法及图象分析技术,对82例鼻咽鳞状细胞癌和25例鼻咽粘膜炎症组织标本进行了定量研究,并对鼻咽癌患者5年生存率与PCNA表达情况进行了相关性分析。结果:①根据PCNA阳性细胞计算的鼻咽癌细胞增殖指数与鼻咽癌的病理分级呈明显的正相关,与患者5年生存率呈明显负相关。②图像处理检测的PCNA表达量与  相似文献   
73.
基础直立倾斜试验对儿童不明原因晕厥的诊断研究   总被引:35,自引:3,他引:35  
为探讨基础直立倾斜试验对不明原因的晕厥患儿的诊断价值,应用直立倾斜试验(倾斜角度60度,试验持续时间45分钟)对42例不明原因的晕厥患儿进行诊断研究,并以13名正常小儿作对照。结果:基础直立倾斜试验在不明原因晕厥患儿的阳性率为67%,对照组阳性率为0。诊断敏感度、特异度及诊断价值分别为67%、100%及74%。阳性反应诱发时间为22±12分钟。在28例阳性反应患儿中,15例为血管抑制型反应,表现为血压明显下降,心率增快;3例为心脏抑制型反应,表现为心率明显下降,血压不变;10例为混合型反应,其血压、心率均明显下降。提示:基础直立倾斜试验可较好地、客观地对血管迷走性晕厥进行诊断。  相似文献   
74.
尼尔雌醇作用下去势雌兔骨组织形态计量学改变   总被引:1,自引:0,他引:1  
目的:评估尼尔雌醇对绝经后骨质疏松症的疗效,并探讨其机理。方法:将30只雌性新西兰兔随机分成3组(每组10只):治疗组[摘除卵巢+尼尔雌醇(每月2mg)]、模型组(摘除卵巢)和正常对照组(假手术),6个月后处死取材,并在处死前行四环素标记,VIDAS图象分析系统下作骨组织形态计量学测定。结果:治疗组的单位体积骨小梁骨量(BV/TV)、相对类骨质量(OV/BV)、成骨细胞指数(OBI)和组织水平的骨形成速率[BFR(T)]明显高于模型组和(或)正常对照组。结论:尼尔雌醇能增加成骨细胞数量,可能是一种成骨细胞募集和(或)增殖的刺激剂。  相似文献   
75.
为探讨小儿咽侧间隙肿瘤的临床特征,报告4例小儿咽侧间隙肿瘤患者儿的诊治体会。结合临床提出诊断本病宜通过CT扫描,先确定肿瘤的大小和范围,再选择颈侧径路摘除肿瘤.结果治疗的4例患儿均获得了肯定的结果。并且提示手术中应保护重要的血管和神经。  相似文献   
76.
头颅X线测量在阻塞性睡眠呼吸暂停综合征诊治中的意义   总被引:29,自引:1,他引:29  
OBJECTIVES: To study the value of cephalometric analysis in the diagnosis, treatment option and evaluation of prognosis. METHODS: A detailed cephalometric analysis was performed using lateral X-ray films from 50 cases with obstructive sleep apnea syndrome (OSAS) and 30 age- and sex-matched controls. RESULTS: Statistical results showed that OSAS patients were different from controls in the following aspects: 1. Their uvula, soft palate and tongue were significantly enlarged. 2. The hyoid bone was displaced inferiorly and posteriorly. 3. The posterior airway space (palatopharyngeal plane) was narrow. 4. The hard palate was elongated. 5. The mandibular body was retropositioned. Fifty unselected consecutive OSAS patients(mean AHI 51.42 +/- 3.96, Medilog SAC 847, Oxford UK) underwent LAUPP using CO2 laser. Twenty-five cases were followed-up for 4-8 months. 10/25 had obtained a reduction in AHI > 50%, 15/25 had AI < 20 times. The success rate was compared with cephalomentric findings. CONCLUSION: Cephalometry has an important diagnostic and predictive value in the clinical investigation of patients suspected of having OSAS.  相似文献   
77.
目的:探讨一氧化氮(NO)和内皮素(Endothelin,ET)在妊高征发病中的变化及其病理意义。方法:用分光光度法和放射免疫法分别定量检测正常妊娠30例(对照组)和妊高征37例(妊高征组)血浆NO和ET的变化。结果:妊高征组血浆NO水平低于对照组(P<0.01),ET水平则高于对照组(P<0.01);妊高征组分娩前后相比,NO水平分娩后升高(P<0.01),ET水平则下降(P<0.01),NO、ET呈显著负相关(P<0.01),NO、ET与平均动脉压均有显著相关性(P<0.01)。结论:NO与ET在妊高征的发病机制中有重要作用,ET/NO失衡可以反映妊高征的病变程度,其病理变化在某种程度上呈可逆性。  相似文献   
78.
本文讨论了以分层法进行中药药效评价时权重设立的问题,主要由以下几部分组成:1.建立递阶层次结构;2.构造两两比较判断矩阵;3.计算单一准则下元素的相对权重;4.计算各层元素的组合权重。由于中药作用具有多途径、多靶点的特性,因此评价过程中权重的设立就占有重要位置。它直接影响对被评价对象药效作用的评判。全面解决中药作用多途径、多靶点药效学评价的数学方法,客观量化的评价中药的综合药效,是中药现代化进程中一个值得研讨的命题。  相似文献   
79.
The facilitatory effectiveness of spindle afferent feedback is controlled by modulation of segmental reflex excitability such that the level of muscle activation is appropriate for the task. Phase-dependent modes of reflex modulation have been well-characterized. We hypothesized that segmental reflex excitability of the triceps surae was also modulated in a manner associated with the activation history of the spindle afferents and the segmental reflex pathway during isometric contractions, standing and stepping. In the first experiment. pairs of soleus (S) H-reflexes were evoked 80 ms apart with equal strength stimuli at rest and while subjects isometrically contracted their S against loads of 10%. 20%. and 50% of their maximum voluntary efforts. The percent depression of the second H-reflex relative to the first was used as a measure of the effect of reflex activation history. At rest, the second H-reflexes were depressed an average of 73% relative to the first. The degree of depression was progressively reduced as the plantarflexion torque increased. In the second experiment, paired H-reflexes were obtained from the S and medial (MG) and lateral gastrocnemii (LG) muscles while subjects were standing and during the stance phase of step initiation. The degree of depression of the second H-reflex during standing ( > 78%) was similar in magnitude to that produced at rest in Experiment I. At the end of the stance phase of stepping. depression of the second H-reflex of all three muscles was reduced to less than 25%. We conclude that the segmental reflex excitability is modulated as a function of the reflex activation history during these tasks.  相似文献   
80.
目的:探讨穿透性角膜移植术(penetratingkeratoplasty,PKP)治疗坏死性基质角膜炎(necrotizingstromalkeratitis)的手术适应证及其临床效果。方法:按照Holland等的HSK新分类法,选择确诊坏死性基质角膜炎患者,予以局部及全身药物治疗。对病情不能控制,药物治疗无效的患者22例(23眼),其中角膜溶解穿孔3眼,用新鲜角膜组织行穿透性角膜移植术,并随访观察术后疗效。结果:随访3mo~3a,22例(23眼)中,术后视力提高者18眼,其中矫正视力达到0.1~0.5者12眼,0.05~0.1者6眼;无改善者5眼。角膜植片透明17眼,半透明2眼,植片混浊4眼,植片透明率为74%。术后3眼植片发生排斥反应,3眼原发病灶复发。2眼术后因排斥反应及原发病灶反复发作,植片完全混浊,行2次角膜移植术。结论:对坏死性基质角膜炎患者,药物保守治疗无效、角膜坏死穿孔或行将穿孔,及时用新鲜角膜组织行穿透性角膜移植术治疗,不仅能控制炎症,缩短病程,而且能保存眼球,恢复部分视力,因此具有重要临床应用价值。  相似文献   
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