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61.
C. I. V. FRANKLIN 《Journal of Medical Imaging and Radiation Oncology》1991,35(1):68-71
The records of 108 adult patients with supratentorial low grade astrocytoma presenting between 1/1/80 and 31/12/87 were examined for the following factors which might affect survival: patient age, extent of surgical resection, site of tumour, tumour grade, radiation field size and radiation dose. Univariate analysis showed that patient age, field size and radiation dose were significant prognostic factors, but with multivariate analysis only patient age and radiation field size were significant independent variables. It is possible that field size is a proxy variable for tumour size. 相似文献
62.
63.
Zongli Lin Meir Pachter Siva Banda Yacov Shamash 《Optimal control applications & methods.》2002,23(1):21-43
A design technique (Control of Uncertain Systems with Bounded Inputs, Tarbouriech S, Garcia G, (Eds), Lecture Notes in Control and Information Sciences, vol. 227 , Springer: Berlin, 1997; 173–186) recently proposed for stabilization of a linear system with rate‐limited actuators is utilized to design feedback laws that cause the system output to track a desired command signal. This design technique combines two design techniques recently developed for linear systems with position limited actuators, piecewise‐linear LQ control (Automatica, 1994; 30 : 403–416) and low‐and‐high gain feedback (IEEE Trans. Automat. Control, 1996; 41 : 368–378), and hence takes advantage of both design techniques, while avoiding their disadvantages. In the case that only the output is available for feedback, the performance of the state feedback law is preserved by the use of a fast observer. An open‐loop exponentially unstable fighter aircraft is used to demonstrate the effectiveness of the proposed control design method. Copyright © 2002 John Wiley & Sons, Ltd. 相似文献
64.
河南食管癌高、低发区无症状人群食管固有膜血管乳头的变化 总被引:2,自引:1,他引:1
目的:探讨食管癌高、低发区无症状居民食管上皮固有膜血管乳头(简称乳头)增生特征(乳头密度和高度)及其与病变分布的关系,加深对食管癌变早期形态学变化特征的了解。方法:2480例无症状人群食管粘膜活检组织,采用食管癌高低发区食管纤维内镜检查,粘膜活检,组织病理学检查和形态学测量技术对食管乳头的分布特征及其与病变的关系进行分析。结果:食管癌高低发区居民食管中、下段乳头升高(≥上皮厚度的1/2)发生率之间差异并不明显(P>0.05),但是,高发区居民食管中段乳头密度(乳头数目/mm)明显高于下段,并高于低发区居民食管中段的乳头密度(P<0.05);高发区居民食管上皮乳头升高伴基底细胞过度增生患者明显高于正常人(P<0.05),而低发区未观察到类似情况。结论:乳头增生表现为乳头数目增多和乳头升高是食管癌高发区人群食管上皮特征性形态学变化,高分区居民上皮乳头升高伴明显基底细胞过度增生,提示乳头增生可能是食管癌变极早期阶段的重要形态学变化,反映了上皮细胞的增生状态。 相似文献
65.
目的:了解温州地区人群不同年龄组骨质疏松患病率及同年龄组男女骨质疏松患病的差异,强调早期预防治疗老年人及绝经期妇女骨质疏松的重要性,方法:应用单能量X线(SXA)骨密度仪测量246例正常人的右跟骨骨密度,结果:男性大于60岁组较小于60岁组骨密度(BMD)降低明显(P<0.05);女性50岁以上组与小于50岁组相比,BMD下降差异有极显性(P<0.01);各年龄组男女相比,男性BMD明显高于女性(P<0.05)。结论:女性骨质疏松症的发病大多以绝经后为主,雌激素在维持骨量方面具有重要的作用。SXA检测的跟骨含95%小梁骨,能较好地确定骨质疏松的风险水平,且其具有价廉、简便,快捷,较准确等特点,故不失为一种较好的临床筛查手段。 相似文献
66.
血管内皮生长因子与乳腺癌临床病理因素及预后的关系 总被引:8,自引:0,他引:8
目的:探讨血管内皮生长因子在乳腺癌中的表达情况及其与预后的关系。方法:采用免疫组化法对1985年至1986年手术治疗的109例乳腺癌的原发灶进行血管内皮生长因子(VEGF)和微血管密度(MVD)检测,并与临床病理资料进行比较分析。结果:VEGF强表达组淋巴结转移率(52.2%)和病理分级明显高于弱表达且(23.5%,P<0.05);随VEGF表达强度的增加,生存率(5年、10年、15年)呈下降趋势,但无明显差异;VEGF与肿瘤大小、绝经状况、雌孕激素受体之间未见相关性。结论:VEGF表达与乳腺癌淋巴结转移和病理分级呈正相关,与预后呈负相关趋势,是估计恶性程度的有用指标,对判断预后有参考价值。 相似文献
67.
M. P. Gosselink J. J. Busschbach† C. M. Dijkhuis§ L. P. Stassen¶ W. C. Hop‡ W. R. Schouten 《Colorectal disease》2006,8(1):15-22
BACKGROUND: After total mesorectal excision for rectal cancer, many surgeons try to avoid an abdominoperineal resection (APR) by performing a transanally double stapled low colo-rectal anastomosis (LRA), frequently without a pouch. This policy is mainly based on the assumption that the quality of life after such LRA is higher than after APR. It has been suggested that a better functional outcome and therefore a higher quality of life might be achieved by a colo-anal J-pouch anastomosis (CPA). The aim of this study was to assess quality of life among disease-free survivors after APR, LRA and CPA. METHODS: The charts of 301 consecutive patients who had undergone surgery for cancer in the middle or lower third of the rectum were analysed. Two hundred four patients were eligible for inclusion. The quality of life among these patients was assessed using one generic (EQ-5D) and two disease-specific questionnaires (EORTC QLQ-C30 and EORTC QLQ-CR38). RESULTS: The response rate was 82%. The median follow-up was 31 months. Overall, quality of life was good but CPA patients had better quality of life scores than APR and LRA patients. This difference was not only due to the better functional outcome but also to the lower incidence of disturbed micturition and sexual problems in the CPA group. CONCLUSION: The quality of life after colo-anal J-pouch anastomosis is better than after abdominoperineal resection (APR) and low colo-rectal anastomosis (LRA). The quality of life after APR is similar to that after LRA. 相似文献
68.
Henry Ho‐Lung Chan 《Clinical & experimental optometry》2005,88(6):410-414
The first‐order kernel analysis in multifocal electroretinogram (mfERG) using low contrast stimulation is suggested as a way to detect the inner retinal responses in animal studies. In this case report, this protocol is applied to human patients with glaucoma to demonstrate the possibility of using mfERG as a tool to detect glaucomatous damage. Two patients with glaucoma were recruited and had mfERG measurements with the 103‐scaled hexagonal stimulus pattern at low (50 per cent) contrast. Their responses were analysed and compared with those from normal subjects with the mfERG measured under the same condition. In the normal subjects, there were obvious oscillatory components on the ascending and descending limbs of the first‐order kernel response to 50 per cent contrast. In the glaucomatous patients, the oscillatory component on the descending limb was obviously diminished. In addition, this component was significantly diminished in the quadrant with a glaucomatous visual field defect. This suggests that the low‐contrast stimulation condition in mERG measurement may provide a good way to detect glaucomatous damage and this may help in clinical diagnosis of glaucoma. 相似文献
69.
70.
目的:检测膀胱移行细胞癌(BTCC)中Mta-1mRNA与蛋白表达,分析其与BTCC临床分期、病理分级、转移及复发的关系。方法:原位杂交、免疫组化方法检测42例BTCC组织Mta-1mRNA与蛋白的表达;CD34标记血管内皮细胞,计数肿瘤组织微血管密度(MVD);结合临床病理资料,分析Mta-1与BTCC的侵袭转移、血管生成及复发间的关系。结果:①Mta-1mRNA与蛋白在BTCC中高度表达,其表达阳性率分别为78.6%、73.8%,与正常组织比较差异有统计学意义(P<0.01),且随BTCC临床分期及病理分级的升高而增加,肿瘤复发组高于无复发组,肿瘤转移组高于无转移组(P<0.05)。②经非参数相关分析发现,Mta-1蛋白与Mta-1mR-NA表达呈高度正相关,Rs为0.945,P=0.000;CD34标染的微血管密度(MVD)与Mta-1mRNA与蛋白表达亦呈正相关,相关系数分别为0.712、0.683,P=0.000。结论:①Mta-1在膀胱移行细胞癌中高度表达,并随着肿瘤临床分期和病理分级的升高而增加,与肿瘤的转移及复发密切相关。②Mta-1参与膀胱移行细胞癌的侵袭、转移,可能与促进血管生成有关。 相似文献