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31.
BACKGROUND: Although normally quiescent, the adult mammalian liver possesses a great capacity to regenerate after different types of injury. Major players in the regeneration process are mature residual cells, including hepatocytes, cholangiocytes and stromal cells. However, if the regenerative capacity of mature cells is impaired, hepatic progenitor cells (HPCs) are activated and expand into the liver parenchyma. Upon transit amplification, the progenitor cells generate new hepatocytes and biliary cells to restore liver homeostasis. AIMS/METHODS: To study the relationship between different histopathological parameters as well as their correlations with clinical parameters and outcome, we examined liver specimens from 74 patients with acute or subacute severe liver impairment by immunohistochemistry for CK7/CK19 (evaluation of HPCs activation/differentiation), Mib1(Ki 67)/P21 (evaluation of proliferative activity/proliferation arrest of hepatocytes) and hematoxylin and eosin (evaluation of hepatocyte loss). RESULTS: Of the 74 patients, 32% survived without transplantation, 14% died without transplantation and 54% were transplanted. Our results show that a threshold of 50% loss of hepatocytes, associated with significant decrease in the proliferative activity of remaining mature hepatocytes, is needed for extensive hepatic progenitor cell activation. Such activation is a sign of disease severity and occurs early (within 1 week) in the disease course. However, development of intermediate hepatocytes, suggesting HPCs differentiation towards mature hepatocytes, takes at least 1 week's time. We found a positive correlation between histopathological parameters (percentage hepatocyte loss, number of proliferating hepatocytes and number of HPCs) and clinical parameters of liver impairment such as model for end stage liver diseases (MELD). Surviving patients compared with those who either died or were transplanted had significantly less hepatocyte loss, less HPCs activation and more mature hepatocyte proliferative activity. Hepatocyte proliferative activity and degree of hepatocyte loss were the most important independent histopathological parameters in predicting outcome. CONCLUSION: Liver biopsy can provide important additional information in a patient with severe acute liver impairment.  相似文献   
32.
目的 设计封堵食管胃吻合口-胸腔瘘的覆膜内支架。方法 根据食管胃吻合口区的特殊解剖结构和吻合口胸腔瘘的病变特点,设计蘑菇状覆膜内支架。透视下,5例吻合口巨大胸腔瘘患者置入6枚蘑菇状覆膜内支架。结果 蘑菇状覆膜内支架能有效封堵食管胃吻合口巨大胸腔瘘,解决了进食问题,改善了营养状况。结论 蘑菇状覆膜内支架结构设计合理,操作简单、安全,近期疗效明显,是一项值得推广的新技术。  相似文献   
33.
Thoracic duct fistula is a rare but potentially serious complication of head and neck surgery. Such fistulae may be difficult to treat, and several techniques, both operative and non-operative, have been advocated. A case of successful surgical treatment of a chronic thoracic duct fistula is presented. The fistula occurred in a 51-year-old female following treatment of a solitary supraclavicular breast metastasis by local excision and radiotherapy. The divided duct was ligated and the area was covered with the clavicular head of the sternocleidomastoid muscle.  相似文献   
34.
Between 10% and 25% of patients with newly diagnosed prostate cancer without bone metastases at the time of diagnosis will develop metastases during follow-up. To determine the value of clinical and biochemical parameters for assessment of prognosis at the time of diagnosis, a retrospective study was performed in 124 consecutive patients with newly diagnosed prostate cancer without bone metastases. The mean follow-up was 41 months, during which time 36 patients died and 15 patients developed metastases. Bone scans were classified from 0 (=normal) through 2 (=abnormal, but not typical for metastases) and were correlated with age, alkaline phosphatase (AP), prostate-specific antigen (PSA), tumour grade, T-stage and N-stage. In patients with a class 2 scan, additional roentgenograms and follow-up were used to exclude metastases at initial stage. All parameters, including therapy, were finally correlated with the development of metastases and survival. For survival 38 patients with proven metastases were used as controls. For all parameters tested, no statistically significant differences were found between the three bone scan classifications. The interval between diagnosis and the development of metastases ranged from 12 to 72 months. For the risk of development of metastases only PSA was found to be a significant correlate (P=0.0075). However, when tumour stages were clustered in limited disease (T0–2) and extensive disease (T3–4), the incidence of metastases was significantly higher in patients with extensive disease than in those with limited disease (P=0.0021). Finally, age, PSA and Anderson classification were found to be significant correlates of survival, but in stepwise analysis PSA was selected as the most prognostic variable (P<0.0001). In contrast with a typical pattern of metastases on bone scintigraphy, an abnormal scan (class 1 and 2) at the time of diagnosis is not a poor prognostic parameter of the risk of death. In conclusion, in patients with prostate cancer without bone metastases at the time of diagnosis, pretreatment PSA and tumour stage can be used for the assessment of risk of development of metastases during follow-up and survival. For this purpose, tumour stage should be clustered in limited and extensive disease. Received 14 April and in revised form 9 June 1997  相似文献   
35.
目的:评估全肠外营养(TPN)对老年晚期消化系统恶性肿瘤病人生存期的影响。方法:回顾性分析121例老年晚期消化系统恶性肿瘤病人TPN治疗后的生存期。结果:TPN治疗后,患者生存期不同程度延长,为9~126天,平均68.1天,多数在两月左右。结论:TPN可延长老年晚期消化系统恶性肿瘤病人的生存期。  相似文献   
36.
早期腭裂修复术后瘘的发生率研究   总被引:5,自引:0,他引:5  
目的 探讨婴儿期腭裂手术后瘘发生的规律。方法 对1995年7月~2001年9月期间施行的2~12个月龄的531例腭裂修复术后瘘发生率进行回顾性分析。结果 全组腭裂术后瘘发生率为4.9%,双侧完全性腭裂术后瘘发生率(7.8%),明显高于不完全性腭裂(4.4%),单侧完全性腭裂(4.3%,P<0.01),后两组之间无显著性差别(P>0.05);术后瘘发生率与年龄,及本组所采用的不同术式无关(P>0.05);其中硬腭部瘘占完全性腭裂术后瘘率70%,较其它部位差异有非常显著性意义(P<0.01)。结论 婴儿期腭裂手术并不会增加瘘发生率,对于双侧完全性腭裂,推荐做术前正畸治疗。  相似文献   
37.
The effect of lithium on slow wave sleep (SWS) was studied in ten normal male volunteers using home based cassette sleep recording and automatic sleep stage analysis. Lithium increased SWS, an effect consisten with a reduction in brain 5-HT2 receptor function.  相似文献   
38.
The combination of a stage model of psychotherapy and treatment manualization has been a major step forward in treatment development and efficacy testing, but not in dissemination. I argue that the technological model of treatment development makes research on the practical application of these technologies difficult. If we continue on our present course, research on dissemination will be uncommon, expensive, and largely irrelevant to the practical issues that need to be faced. It makes more sense to proceed directly to dissemination research. Alternative methods, including manipulated training designs, will permit this, but these fundamentally challenge the implicit assumptions of the stage model.  相似文献   
39.
第2产程剖宫产术对母婴的影响   总被引:1,自引:0,他引:1  
本文对我院近 4年来第 2产程 (以下简称 2程 )剖宫产 6 1例进行回顾性分析。资料表明 :第 2产程剖宫产术易合并羊水污染及术时并发症 ,新生儿Apgar氏评分低 ,术后并发症高于对照组 (P <0 .0 5 ) ,提示第 2产程剖宫产术比一般头位急症剖宫产术对母婴不利 ,其并发症的发生与第 2产程的延长相关 (P <0 .0 1) ,故应把握时机尽量减少宫口开全后施行剖宫产。  相似文献   
40.
目的 观察哮喘缓解期联用乌体林斯、黄芪注射液、鱼腥草注射液穴位注射控制哮喘发作的疗效 ,探讨其作用机理。方法 哮喘缓解期患者 5 6例 ,随机分成两组。治疗组 3 2例采用相同穴位交替选择药物 ,隔日穴位注射治疗 ;对照组 2 4例予常规治疗。并观察两组疗效及治疗前后用力肺活量 (FVC) ,1秒钟用力呼气量 (FEV1)和肺活量 (VC)的变化。结果 两组总有效率为 96.87%和 79.17% ,治疗组优于对照组 ( χ2 =10 ,P <0 .0 1)。治疗组治疗前后肺功能明显改善 ,治疗前后比较VC分别为 ( 1.79± 0 .43 )L和 ( 2 .91± 0 .64 )L ,P <0 .0 5 ;FVC分别为 ( 1.64± 0 .46)L和 ( 2 .0 9±0 .62 )L ,P <0 .0 5 ;FEV1分别为 ( 0 .92± 0 .70 )L和 ( 1.3 5± 0 .3 5 )L ,P <0 .0 5。对照组治疗前后肺功能改善不明显 (P均<0 .0 5 )。治疗组明显优于对照组。结论 在哮喘缓解期联用乌体林斯、黄芪注射液、鱼腥草注射液穴位注射控制哮喘发作的临床疗效优于常规治疗  相似文献   
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