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81.
目的探讨肺动脉栓塞多排螺旋CTA血管成像扫描延迟时间的最佳值,最佳肺动脉血管成像。方法收集了45例肺动脉栓塞多排螺旋CTA血管成像,造影剂用量按1.5ml/kg,注射速率3ml/sec。扫描延迟时间用Bolus Tracking第一组20例;test Bolus为二组15例;常规计算时间为一组10例。准直器宽度2.5mm,层厚3mm。数据重建用最大密度投影(MIP)和容积显示(VR3D)等常规方法。一、二、三组图像分别由两位高年资医师阅片。结果第一组20例中19例和第二组15例图像肺动脉均清晰显示。第三组10例中4例图像模糊,第三组与第一、二组图像质量有显著差异。结论肺动脉栓塞CTA血管造影中扫描延迟时间用Test Bolus和Bolus Tracking较优,常规计算时间延迟图像质量较差。 相似文献
82.
G P H Gui D J Joubert R Reichert A Ward S Lakhani P Osin A Nerurkar R A'Hern K Benson S R Underwood 《European journal of surgical oncology》2005,31(7):707-714
INTRODUCTION: Sentinel lymph node biopsy (SLNB) has become increasingly accepted as a diagnostic method to stage the axilla in breast cancer, selecting women with a positive sentinel node for completion axillary clearance. As SLNB became established, many surgeons supplemented SLNB to sample a minimum of four lymph nodes, on the assumption that the four-node technique is supported by randomised trial data. We hypothesised that the practice of undirected sampling to supplement SLNB adds little information to the status of the residual axilla. METHODS: One hundred and sixty-five patients with early breast cancer were studied. Following successful identification of the sentinel node, 84 women had completion axillary dissection and 81 women had an axillary sample with at least four nodes available for pathological assessment. RESULTS: Following successful identification of the sentinel node in 165 patients, the false negative rate (FNR) was 2/44=4.5% (95% CI 0.6-15.5), sensitivity 42/44=95.5% (84.5-99.4) and negative predictive value (NPV) 121/123=98.4% (94.2-99.8). In the axillary dissection cohort, the FNR was 2/26=7.7% (0.9-25.1), sensitivity 24/26=92.3% (74.9-99.1) and NPV 58/60=96.7% (88.5-100). In the axillary sample group, the FNR was 0/18=0% (0-18.5), sensitivity 18/18=100% (81.5-100) and NPV 63/63=100% (94.3-100). The SLNB was the only positive node in 12/26 (46.2%) in the axillary dissection group and 10/18 (55.6%) in the axillary sampling group. There was no patient in the axillary sampling group where the sample node was positive and the sentinel node negative. CONCLUSION: Once SLNB is validated within the multidisciplinary unit, undirected sampling of the axilla following identification of the sentinel node(s) is unnecessary. The additional sampling of non-sentinel nodes has no role to play either in the assessment of a potential false negative SLNB nor as predictive information on the status of the residual axillary nodes. 相似文献
83.
目的 :测定汉防己甲素在家兔血浆中的浓度。方法 :采用兔耳缘静脉注射给药方式 ,按不同时间间隔颈动脉取血 ,采用HypersilODS C18柱 ,以甲醇 水 ( 4 5∶5 5 )为流动相 ,检测波长 2 10nm ,以延胡索乙素为内标。结果 :标准曲线回归方程为Y =0 .5 318X 0 .0 6 88,(γ =0 .996 2 ) ,汉防己甲素在 0 .5 6 2 5~ 18μg·ml-1浓度范围内与峰面积比值呈良好的线性关系 ,平均加样回收率 88.5 % ,日内及日间RSD分别为 3.1%和 4 .7%。结论 :本方法简便、快速、可靠 ,可为汉防己甲素的其他生物样品分析提供参考 相似文献
84.
人参皂苷Rg1抗衰老作用可能与改变p16、cyclin D、CDK4的表达有关 总被引:7,自引:0,他引:7
目的 :探讨人参皂苷Rg1对抗三丁基过氧化氢 (t BHP)诱导的WI 38细胞衰老作用及其可能细胞周期调控机制。方法 :将WI 38细胞随机分为 4组 ,用不同剂量Rg1预处理。从 30代开始 ,隔代用t BHP作用 ,每次 1h ,共 4次 ,诱导细胞衰老。从光镜、透射电镜观察细胞形态及超微结构 ;流式细胞术分析G1期细胞比例 ;以及SA β 半乳糖苷酶的细胞化学染色 ,确定Rg1的抗衰老作用。并采用免疫印迹技术对CDK4、cyclinD1和p16等表达情况进行检测。结果 :Rg1预处理组与单纯t BHP处理组相比 ,细胞形态体积小、胞体不如后者扁平 ,次级溶酶体减少 ,G1期细胞比例下降 ,SA β 半乳糖苷酶染色阳性细胞百分比下降 ,说明Rg1在t BHP诱导细胞衰老模型中有抗衰老作用。进一步发现用Rg1预处理后 ,p16、cyclinD1表达水平降低、CDK4表达水平增加。结论 :提示Rg1可能通过改变细胞周期调控因子的表达而发挥其抗t BHP诱导的WI 38细胞衰老作用。 相似文献
85.
目的 :探讨无鼻咽部症状的鼻咽癌患者颈淋巴结转移临床误诊原因。方法 :行细针穿刺细胞学检查淋巴结 ,纤维鼻咽镜活检病理证实鼻咽癌。结果 :鼻咽癌患者颈部淋巴结转移 4 9例 ,误诊为颈部淋巴结炎 33例 (细胞学诊断鳞状细胞癌 10例 ,腺癌 4例 ,未分化癌 16例 ,类型未定转移癌 3例 ) ;误诊为淋巴结核 13例 (细胞学诊断鳞状细胞癌 3例 ,腺癌 2例 ,未分化癌 7例 ,类型未定转移癌 1例 ;误诊为霍奇金病 3例 ,细胞学诊断未分化癌 2例 ,类型未定转移癌 1例 )。纤维鼻咽镜活检病理均为鼻咽癌。结论 :无鼻咽部症状的鼻咽癌患者颈部淋巴结肿大 ,行穿刺细胞学检查对明确诊断有指导意义 相似文献
86.
BRD7基因转染对鼻咽癌细胞生长的抑制作用 总被引:15,自引:2,他引:15
目的:探讨鼻咽癌负相关基因BRD7对鼻咽癌细胞系HNE1生长的影响。方法:构建BRD7基因真核表达载体pcDNA3.1( )/BRD7重组体,采用脂质体介导转染技术,将BRD7真核表达重组粒和空载体质粒分别导入鼻咽癌细胞系HNE1,Southern杂交和RT-PCR分别检测外源性DNA的整合和BRD7基因的表达,并借助细胞生长曲线、软琼脂集落形成试验、流式细胞计数和裸鼠接种方法对转染细胞的生物学行为进行了检测。结果:转染BRD7基因的HNE1生长倍增时间为53h,较HNE1(23.9h)和空载体转染HNE1(24.1h)明显延长,流式细胞仪表明,BRD7表达升高延缓细胞由G0-G1期进入S期,BRD7转染HNE1在软琼脂中集落形成率较对照组显著下降(P<0.01),裸鼠接种试验显示BRD7基因转染细胞HNE1生长速度受到抑制。结论:BRD7基因重表达有助于HNE1的恶性表型的逆转;BRD7是一个鼻咽癌相关的抑瘤基因良好的候选者。 相似文献
87.
88.
目的:评价乾坤胶囊治疗肺癌的临床疗效并探讨该复方中药制剂抗肺癌的作用机理.方法:对100例经细胞病理学证实的肺癌患者,随机分为乾坤胶囊组(胶囊组)34例,化疗组33例,化疗 胶囊组(综合组)33例.从临床症状、免疫指标、血象、生活状态(Karnofsky评分标准)、体重及p53、PCNA的表达等方面进行了前瞻性对比治疗研究.结果:胶囊组、综合组、化疗组的总有效率分别为94.1%、90.9%、57.5%.经统计分析,胶囊组、综合组与化疗组比较均有显著性差异(P<0.01及P<0.05).显示乾坤胶囊对肺癌患者能明显改善症状、增加体重、有效地提高生存质量、显著地提高细胞免疫功能(NK细胞、LAK细胞、IL-2、CD3、CD4、CD4/CD8)、降低p53及PCNA阳性细胞数.结论:乾坤胶囊治疗肺癌疗效确切,无不良反应.其机理是全面提高患者的免疫功能,抑制p53及PCNA的表达. 相似文献
89.
90.
ObjectiveTo analyze the use of packed red blood cells (PRBCs) for patients with pelvic fracture and evaluate factors associated with PRBC transfusion for patients with pelvic fracture.MethodsThis retrospective cohort study collected 551 patients with pelvic fractures from six hospitals between September 1, 2012, and June 31, 2019. The age span of patients varied from 10 to 95 years old, and they were classified into two groups based on high‐energy pelvic fractures (HE‐PFs) or low‐energy pelvic fractures (LE‐PFs). The study''s outcome was the use of PRBCs, fresh frozen plasma (FFP), and albumin. Demographic data, characteristics, laboratory tests, clinical treatment details, and clinical outcomes were compared between the two groups. Factors that were statistically associated with perioperative PRBCs in univariate analyses were included to conduct an optimal scale regression to determine the independent factors for perioperative PRBCs.ResultsA total of 551 patients were screened from six hospitals, and after inclusion and exclusion, 319 were finally included and finished the follow‐up from admission to discharge, while four patients died during hospitalization. Three hundred and nineteen patients were classified into two groups by their injury mechanisms. A total of 230/319 (72.1%) patients were classified into the HE‐PF group, and 89/319 (27.8%) patients were classified into the LE‐PF group. Patients in the HE‐PF group were transfused with 4.5 (3–8) units of PRBCs, 300 (0–600) ml of FFP, and 0 (0–30) g of albumin, while patients in the LE‐PF group were transfused with 3.5 (2–4.5) units of PRBCs, 0 (0–295) ml of FFP, and 0 (0–0) g of albumin (all P < 0.001). There were higher proportions of male patients and patients under 65 in the HE‐PF group (all P < 0.001). HE‐PF group patients were more severely injured and likely to take external fixation. The optimal scale regression revealed four significant factors associated with perioperative transfused PRBCs, which were patients on admission with hemorrhagic shock (importance = 0.283, P = 0.004), followed by fracture types identified by Tile classification (importance = 0.156, P < 0.001), hemoglobin levels below 70 g/L on admission (importance = 0.283, P = 0.004), followed by fracture types identified by Tile classification (importance = 0.156, P < 0.001), hemoglobin levels below 70 g/L on admission (importance = 0.148, P = 0.039), and methods of pelvic fixation (importance = 0.008, P = 0.026), ranked by the importance.ConclusionPatients with HE‐PFs had increased transfusions of PRBCs, FFP, and albumin, and hemorrhagic shock on admission, Tile classification, Hb levels, and stabilization methods were found to be associated with perioperative PRBCs. 相似文献