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11.
Gregory J. Nason Khaled Ajib Guan Hee Tan Dixon T.S. Woon George T. Christakis Robert K. Nam 《Canadian Urological Association journal》2021,15(4):E199
IntroductionPatients with renal cell carcinoma (RCC) with level 3 or 4 caval thrombus have a poor prognosis, with reported five-year survival rates of 30–40%. The aim of this study was to assess the perioperative morbidity and long-term oncological outcomes for radical nephrectomy with resection of vena cava thrombus using a combined surgical approach, including extracorporeal circulation and deep hypothermic circulatory arrest.MethodsA retrospective review was performed of the institutional case log to identify all radical nephrectomies with caval thrombus performed from January 2006 to May 2020.ResultsTwenty-five patients were identified with level 2 thrombus in one (4%), level 3 thrombus in eight (32%), and level 4 in 16 (64%). The median followup was 20.6 months (range 0.2–133.3). The median age at surgery was 68.4 years (range 44.2–85.5). Twenty-one (84%) patients were symptomatic at presentation. Six (24%) patients had distant metastases at diagnosis. The median circulatory arrest time was 15 minutes (range 6–35). The 30-day grade ≥3 complication rate was 8%. The 30-day mortality rate was 8%. The one-year, two-year, three-year, and five-year recurrence-free survival (RFS) rates were 53%, 18%, 10%, and 10%, respectively. The median time to systemic treatment was 7.7 months (range 1.2–25.7). The one-year, two-year, three-year, and five-year overall survival (OS) rates were 70%, 43%, 36%, and 31%, respectively.ConclusionsRadical nephrectomy with resection of vena cava thrombus using extracorporeal circulation and deep hypothermic circulatory arrest is associated with some morbidity and mortality but remains a safe and effective strategy for advanced RCC patients who would otherwise be managed palliatively. 相似文献
12.
The practical performance of algebraic reconstruction techniques (ART) for computed tomography (CT) depends heavily on the order in which the projections are considered. Complete orthogonalization, notwithstanding its theoretical justification, is not feasible because the computational time is prohibitive. The authors report here a scheme that yields the most efficient reconstruction without orthogonalization: projections are organized and accessed in a nominally multilevel fashion. Each level makes the best use of the image information reconstructed in the preceding levels. If the number of projections is a power of two. Then the access orders are exactly that for the 1D FFT. The authors' scheme can be easily implemented. Using it, one iteration of ART yields a high-quality image. Experimental results of this algorithm are demonstrated and compared with the results from the conventional sequential method and also random ordering. Comparisons show that this scheme is superior. ART is better in image quality than the Fourier back-projection algorithm, at least for a smaller number of projections. Since the authors have made it much more efficient in computational speed, ART could now find widespread use in medical imaging. 相似文献
13.
Jeffrey M. Trent Barbara Weber X. Y. Guan Ji Zhang Francis Collins Ken Abel Austin Diamond Paul Meltzer 《Breast cancer research and treatment》1995,33(2):95-102
Summary The recognition of recurring sites of chromosome changes in malignancies has greatly facilitated the identification of genes implicated in the pathogenesis of human cancers. Based especially upon recent studies [1–4], it appears increasingly likely that a subset of recurring chromosome alterations will be recognized in human breast cancer. Currently recognized chromosome changes characterizing breast carcinoma include the recognition of cytologic features of gene amplification (e.g. double minutes [dmins] and homogeneously staining regions [HSRs]) [5–8]. As these and other chromosome regions are implicated in recurring abnormalities in breast cancer, it will become increasingly important to have band-or region-specific genomic libraries and probes in order to facilitate high resolution physical mapping and ultimately to clone breast cancer related genes [9]. Toward this end an important recent development in physical mapping has been the establishment of chromosome microdissection as a rapid and reproducible approach to rapidly isolate and characterize chromosome region-specific DNA, greatly facilitating the initial steps in positional cloning of disease-related genes [10–13]. In this brief report, we will highlight the application of chromosome microdissection to the generation of region-specific probes for both fluorescent in situ hybridization (FISH) and the generation of genomic microclone libraries. Additionally, efforts using this methodology to generate a microclone library encompassing the early onset breast/ovarian cancer (BRCA1) gene will be presented.Presented by Jeffrey M. Trent at the 16th Annual San Antonio Breast Cancer Symposium, San Antonio TX, USA, November 4, 1993; Minisymposium on Molecular Genetics in Breast Cancer. 相似文献
14.
高校离退休老人躯体健康与心理状况的相关性研究 总被引:10,自引:1,他引:9
目的:了解离退休老人躯体健康和心理状况的关系。方法:采用CMI和SCL-90对225名高校离退休老人进行调查,分析两者的关系。结果:既往健康状况、神经系统疾病和躯体化成正相关;强迫与呼吸系统疾病成正相关,与心血管系统疾病成负相关;疲劳感和敌对成负相关,和睡眠饮食障碍成负相关。结论:维持老人心身健康,主要在于防治慢性疾病和神经系统疾病,以及对躯体化障碍和强迫症状的干预 相似文献
15.
以蔓荆子黄素为指标,用反相 HPLC法测定了蔓荆子中的含量,实验采用 C_(18)柱,以甲醇-0.4%磷酸溶液(60: 40)为流动相,检测波长 258nm,用外标法测定,回收率为 98.18%,RSD1.46%,线性范围 0.15~0.75μg。本法快速简便,重现性好,为蔓荆子质量控制提供了可靠的依据。 相似文献
16.
目的:研究可否用左室重量表达并判定左心功能不全的可能性。方法:将左心功能不全按NYHA标准分成4个级别,每级1组,并设正常对照组,用超声心动图测量同一个病人的左室射血分数(LVEF)和左室重量。用SAS统计软件做方差分析。结果:LVEF与左心功能不全高度负相关(R=-0.77270),左室重量与左心功能不全高度正相关(R=0.73421)。LVEF、左室重量各级指标间差别显著(n=153,F=64.85,P<0.01;n=153,F=53.39,P<0.0001)。各级与对照组比统,LVEF指标从Ⅱ级开始方有显著差别(P<0.05);而左室重量指标从Ⅰ级开始就有显著差别(P<0.05)。结论:LVEF与左室重量指标均与左心功能不全高度相关,但心功能Ⅰ级的病人,左室重量指标更为敏感。 相似文献
17.
晶状体上皮细胞PAI—1蛋白酶mRNA的表达 总被引:1,自引:0,他引:1
研究从转录水平确定晶状体上皮细胞是否能够合成纤麦原激活物抑制物-1蛋白酶。方法体外培养的牛晶状体上皮细胞,当细胞生长融合后,抽提RNA;采用Nothernblot分析技术,对抽提得到的牛晶状体上皮细胞RNA用特异的cDNA探针进行检测。结果在牛晶状体上皮细胞的基因转录产物中存在有PAI-1mRNA的表达,所表达的PAI-1mRNA碱基长度为2.3kb。结论牛晶状体上皮细胞能够分泌PAI-1蛋白酶: 相似文献
18.
目的评价睫状体冷冻术联合巩膜穿刺术在治疗绝对期青光眼中的应用。方法对绝对期青光眼47眼施行睫状体冷冻术联合巩膜穿刺术,观察术后3a内眼压变化。结果全部病例术后高眼压症都获缓解,对术后早期眼压反弹,本术较单纯施行睫状体冷冻术者控制眼压疗效好(P<0.01),且无副作用和并发症。结论睫状体冷冻术联合巩膜穿刺术是治疗绝对期青光眼更简便、安全、有效的手术选择。 相似文献
19.
慢性肾衰继发性甲旁亢iPTH水平变化的临床意义及罗钙全疗效观察 总被引:2,自引:0,他引:2
目的探讨慢性肾功能衰竭(CRF)并发继发性甲状旁腺机能亢进(SHPT)血中全段甲状旁腺激素(iPTH)水平变化的临床意义及小剂量罗钙全对慢性肾衰继发甲旁亢早期的疗效观察。方法分别采用免疫放射法、苦味酸法、偶氮胂Ⅲ法、直接紫外法测定60例健康体检者和94例CRF患者血iPTH、Cr、Ca、P含量;取iPTH含量87.5~295ng/L的SHPT病人随机分为观察组和治疗组各23例,治疗组每天口服罗钙全0.25ug。结果血iPTH水平随肾功能损害的加重而逐渐升高,与Cr成正相关,P亦逐渐升高,Ca则逐渐降低;治疗组服药3个月后,血iPTH显著降低(P<0.05),Ca明显升高(P<0.05),P无显著性差异(P>0.05),观察组血iPTH显著升高(P<0.05)。结论iPTH可作为早期诊断CRF继发性甲旁亢的敏感指标且其水平与肾功能损害程度一致;口服小剂量罗钙全治疗早期SHPT的疗效与iPTH水平有关。 相似文献
20.
Exposure of cells to heat inhibits a number of nuclear activities associated with semi-conservative replication of DNA including the incorporation of radiolabelled precursors into acid-insoluble DNA, the initiation of new replicons, the elongation of the DNA fibre at the replication fork, the synthesis and deposition of new histones into chromatin and the reorganization of nascent DNA into mature chromatin. These effects are likely to underlie the heat sensitivity of S-phase cells and may contribute to the radiosensitization observed in this phase of the cell cycle. While some of these effects may be explained as 'passive' consequences of heat-induced damage on chromatin structures experiments reviewed here point to the activation of a checkpoint as a contributing factor to the observed inhibition of DNA replication. Activation of a heat responsive S-phase checkpoint targets the activity of RPA via interaction with nucleolin. Nucleolin, a major nucleolar protein, is found normally sequestered in the nucleolus. Exposure of cells to heat causes a rapid translocation of nucleolin from the nucleolus into the nucleoplasm that enables RPA/nucleolin interaction. This interaction inhibits functions of RPA associated with the initiation of DNA replication and contributes to the immediate inhibition of DNA synthesis observed after heat shock. The results suggest that the nucleolus serves as a sequestration centre for the temporary inactivation of regulatory molecules, such as nucleolin, capable of regulating essential cellular functions after heat shock. It is speculated that this regulatory process is integrated in the network of responses that determine cell sensitivity to heat and that it may be involved in heat radiosensitization to killing as well. 相似文献