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11.
The prolonged half-life of mutant p53 makes feasible its immunocytochemical detection. In order to assess the pathogenetic role of mutant p53 in regenerative and neoplastc liver disease we studied its immunohistochemical expression in cases of hepatic cirrhosis, hepatocellular carcinoma (HCC), cirrhosis with areas of HCC, hepatocellular adenoma and focal nodular hyperplasia. The study included needle and wedge biopsies of 50 cirrhotic livers, 59 HCCs (36 of them with associated cirrhosis), six adenomas and two focal nodular hyperplasias. Sixty-five HCC fineneedle cytology specimens were also included in the study. There was no immunohistochemical evidence of mutant p53 expression in any of the cases of cirrhotic liver (except for one instance associated with HCC) adenoma or focal nodular hyperplasia. In contrast p53 was detected in 8.5% of HCC cases in the biopsy series and 24% of HCC cases in the fine needle aspiration series. In addition, mutant p53 expression in HCC was positively correlated with tumour grade. According to grade, the distribution of p53 positive immunoreactivity among HCCs was as follows: Grade I-II, 0% of cases in the biopsy series and 9% in the fine needle aspirates; Grade III, 18% in the biopsy series and 55% in the fine needle aspirates; and Grade IV, 40% in the biopsy series. Therefore, mutant p53 expression does not seem to be associated with benign liver lesions but seems to correlate with the progression of HCC through various grades of increasing malignancy.  相似文献   
12.
目的 分析放射工作者外周血象、淋巴细胞微核及染色体畸变情况,为放射工作者职业防护和健康监测提供依据。方法 对2015年、2017年和2019年连续3次接受健康检查的127名放射工作者进行淋巴细胞微核、染色体及血象分析,将其设为放射组。另外选取133名无射线接触史的医务人员设为对照组;结果 放射组中淋巴细胞微核率和染色体畸变率高于对照组,白细胞和血小板计数低于对照组,均具有统计学意义(P < 0.05)。127名放射工作者外周血白细胞总数随着接触电离辐射时间的增长逐渐降低,染色体畸变率逐渐增加,均具有统计学意义(P < 0.05)。损害工龄大于20年的放射工作者染色体畸变率高于低工龄组,不同损害工龄之间比较无统计学意义(P > 0.05)。核医学与介入治疗工种染色体畸变率高于其他工种,具有统计学意义(P < 0.05)。结论 长时间接触低剂量电离辐射可使放射工作者白细胞总数降低和淋巴细胞染色体畸变率增加,应加强放射工作者防护措施以备降低电离辐射损伤程度,特别要加强核医学和介入治疗放射工作人员的职业防护。  相似文献   
13.
14.
彩色多普勒超声心动图诊断肺心病的临床价值   总被引:1,自引:1,他引:0  
目的:阐述彩色多普勒超声心动图(CDE)诊断肺心病的临床价值。方法:通过CDE对临床上拟诊的肺心病患者进行肺动脉高压(PH)定性、定量的诊断、并观测由PH继发引起心脏在CDE上的异常改变。结果:CDE测定PH44例(88%),其肺动脉收缩压(SPAP)>36mmHg,6例(32mmHg≤SPAP<36mmHg,确诊CPM的临床符合率665(50/76)。结论作为无创性诊技术,CDE估测PH或诊断CPM准确简便,重复性强,对于指导临床治疗意义重大。  相似文献   
15.
目的:检测B7基因在肾细胞癌的表达及其与肾细胞癌分级、分期及预后的关系。方法:本文应用RTPCR和免疫组织化学技术检测了22例肾细胞癌组织B7的表达。结果:RTPCR5例阳性,免疫组化4例阳性,B7mRNA表达与肾癌病理分级、分期无关系;病理切片HE染色显示,B7阳性肿瘤组织内淋巴细胞浸润明显增多。结论:表达B7的肿瘤组织局部抗肿瘤免疫反应增强,提示B7表达可能与肿瘤预后有关。大部分泌尿系肿瘤不表达B7,为转B7基因治疗泌尿系肿瘤提供了理论依据。  相似文献   
16.
Details on all cases of hepatitis A notified in North Queensland in 1996 and 1997 were prospectively collected. There were two substantial outbreaks and a total of 225 cases during this period. The total incidence rate (per 100,000) was 11.0 in 1996 and 27.0 in 1997. Aborigines and Torres Strait Islanders constituted 29% of cases and had incidence rates of 75.2 and 62.7 per 100,000 for 1996 and 1997 respectively. Thirty-nine cases (17.3%) were admitted to hospital for a total of 202 bed-days and a 4 year old died with fulminating hepatitis. A probable source of infection was identified for 69% of cases. The common risk categories for infection were: living in or visiting a rural Aboriginal or Torres Strait Islander community, injecting drug use, contact with a known case of hepatitis A, and travel to countries with endemic hepatitis A.  相似文献   
17.
The efficacy of the temporary oxygen carrier perflubron emulsion (PFC) in maintaining oxygen delivery, tissue oxygenation, high-energy phosphates (HEPs), and myocardial function was investigated during low-flow ischemia. Perfusion rate, oxygen tensions, and cardiac function were measured during stabilization (5 min), controlled-flow (22 ml/min x 20 min), and low-flow (0.22 ml/min x 120 min) periods in isolated rabbit hearts. Hearts were perfused with Krebs-Henseleit (KH) solution (Control), or 10 or 20% PFC (vol/vol; n = 8 per group) 5 min before and throughout the low-flow period. Myocardial tissue was then frozen for biochemical and metabolic measurements. Myocardial oxygenation was measured at incremental flow rates by using 20% PFC (n = 4) or KH (n = 6). In PFC hearts, oxygen delivery and intramyocardial tissue Po2 were improved at all evaluated time points and flow rates, respectively (p < 0.05). In Control hearts, left ventricular end-diastolic pressure was elevated at 60, 90, and 120 min of low-flow ischemia (p < 0.05). Tissue lactate was higher (p < 0.05) and HEPs lower (p < 0.05) in Control hearts during low-flow ischemia. These results indicate that PFC treatment improves myocardial oxygenation, maintains HEPs, prevents ischemic contracture, and may increase the margin of safety during low-flow ischemia in isolated rabbit hearts.  相似文献   
18.
蒙药忠论-5胶囊总生物碱测定及其体外溶出度研究   总被引:2,自引:0,他引:2  
目的 考察蒙药忠伦-5胶囊中总生物碱含量及其体外溶出情况。方法 以苦参碱为对照品,利用酸性染料比色法测定总生物碱;以水为介质,用转篮法考察其体外溶出度。结果 含量测定方法精密度为RSD=1.89%,平均回收率为100.89%,RSD=3.49%。;苦参总生物碱相对累积溶出度与溶出时间相关显著(P<0.01),T50=24min,Td=31min,m=1.32。结论 用上法测定总生物碱含量及体外溶出度,对评估忠伦-5胶囊质量有实用价值。  相似文献   
19.
The purpose of this study was to prospectively examine the effectiveness and tolerability of a simple radiotherapy technique for the palliation of symptomatic liver metastases. Twenty‐eight patients with symptomatic liver metastases were enrolled from seven centres, and received targeted (partial or whole) liver irradiation consisting of 10 Gy in two fractions over 2 days. Symptoms at baseline were hepatic pain (27 patients), abdominal distension (19), night sweats (12), nausea (18) and vomiting (eight). Twenty‐two patients (76%) had failed previous treatment with chemotherapy, hormonal therapy and/or high‐dose steroids. Symptoms and potential toxicities were prospectively assessed at the time of treatment, then 2, 6 and 10 weeks later. Individual symptom response rates were 53?66% at 2 weeks. Partial or complete global symptomatic responses were noted in 15 patients (54%) overall. The treatment was well tolerated with two patients (7%) experiencing grade 3 toxicity (one vomiting and one diarrhoea); however, four patients reported temporary worsening of pain shortly after treatment. This simple and well‐tolerated treatment achieves useful palliation.  相似文献   
20.
McKeown-Eyssen (Cancer Epidemiol. Biomarkers Prevent., 3, 687-695, 1994) and Giovannucci (Cancer Causes Control, 6, 164-179, 1995), noting the striking similarity in lifestyle risk factors for colorectal cancer and insulin resistance, proposed that the hyperinsulinemia, glycemia and hypertriglyceridemia associated with insulin resistance promotes colon cancer. To compare the effect of diet on colon cancer promotion and insulin resistance in the F344 rat, we assessed the effect of fat, n-3 fatty acids and energy in pairwise comparisons on average size of aberrant crypt foci (ACF) and on glucose intolerance in the same animals in a single experiment. Diets high in fat and energy increased and diets with increased n-3 fatty acids and calorie restriction decreased both ACF growth and glucose intolerance compared with control diets. The measures of promotion of colon cancer and insulin resistance were strongly correlated (n = 98, r = 0.67, P < 0.001). In addition, both were highly correlated with daily energy intake (r = 0.62 and 0.66) and were also correlated with basal (post-prandial) insulin, glucose and triglycerides (r = 0.31-0.53, P < 0.01). We concluded that ACF growth and glucose intolerance are correlated for a wide range of diets and that increased circulating energy (glucose and triglycerides) may lead to both colon cancer promotion and insulin resistance.   相似文献   
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