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111.
Elucidating the mechanism of liver tumor growth and metastasis after hepatic ischemia-reperfusion (I/R) injury of a small liver remnant will lay the foundation for the development of therapeutic strategies to target small liver remnant injury, and will reduce the likelihood of tumor recurrence after major hepatectomy or liver transplantation for liver cancer patients. In the current study, we aimed to investigate the effect of hepatic I/R injury of a small liver remnant on liver tumor development and metastases, and to explore the precise molecular mechanisms. A rat liver tumor model that underwent partial hepatic I/R injury with or without major hepatectomy was investigated. Liver tumor growth and metastases were compared among the groups with different surgical stress. An orthotopic liver tumor nude mice model was used to further confirm the invasiveness of the tumor cells from the above rat liver tumor model. Significant tumor growth and intrahepatic metastasis (5 of 6 vs. 0 of 6, P=0.015), and lung metastasis (5 of 6 vs. 0 of 6, P=0.015) were found in rats undergoing I/R and major hepatectomy compared with the control group, and was accompanied by upregulation of mRNA levels for Cdc42, ROCK (Rho kinase), and vascular endothelial growth factor, as well as activation of hepatic stellate cells. Most of the nude mice implanted with liver tumor from rats under I/R injury and major hepatectomy developed intrahepatic and lung metastases. In conclusion, hepatic I/R injury of a small liver remnant exacerbated liver tumor growth and metastasis by marked activation of cell adhesion, invasion, and angiogenesis pathways.  相似文献   
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BACKGROUND: The cerebral ischemia and ischemia/reperfusion animal models are used to simulate the human cerebrovascular diseases is one of the popular topics of neurological science recently. To study the pathophysiology, pathogenesis, prophylaxis and treatment of ischemic cerebrovascular diseases and to establish the ideal animal model that is the most similar to the human cerebral ischemia, are the topics that the people generally cared about. OBJECTIVE: To evaluate the effects of aerocyst-blocking bilateral ascending pharyngeal artery on the establishment of cerebral ischemia models by using digital subtraction angiography (DSA), magnetic resonance diffusion-weighted imaging (DWI) and magnetic resonance perfusion-weighted imaging (PWI). DESIGN: Repetitive measure animal experiment. SETTING: Zhongshan Hospital Affiliated to Dalian University. MATERIALS: The experiment was carried out in the Animal Laboratory (Provincial Laboratory), Zhongshan Hospital of Dalian Univeristy from January to May 2006. A total of 14 domestic piglets, of 6 months old, weighing 12–15 kg, of either gender, were selected from Animal Experimental Center, Dalian University. Multistar T.O.P digital subtraction angiography machine was provided by Siemens Company, German. METHODS: Aerocyst-blocking bilateral ascending pharyngeal artery was used to establish cerebral ischemia models. And then, Multistar T.O.P. DSA was used for imaging of cerebral vessels before blocking, during blocking and at 0.5 and 2 hours after ischemia perfusion. GE Signa 1.5 T supraconduction magnetic resonance imaging was used for DWI examination; in addition, PWI was used based on focal sites and areas. Otherwise, magnetic resonance imaging (MRI) was used to detect signal changes of T1WI and T2WI in ischemic areas. MAIN OUTCOME MEASURES: Analytic results of DSA, DWI, PWI and MRI. RESULTS: All 14 experimental piglets were involved in the final analysis. ① DSA: The blood flow of bilateral ascending pharyngeal arteries and its branch were blocked at blocking phase, which restored 0.5 and 2 hours after reperfusion. ② DWI and PWI: There were no observable abnormalities in PWI and DWI at pre-blocking. Abnormal increased signals were found on both DWI and PWI at during and post-blocking. There were reduction in ADC and rCBF and delay in rTTP at all time points except pre-blocking. ③ MRI: There were no abnormal signals observable at any time of pre- and post-blocking in T1WI and T2WI. CONCLUSION: It is feasible to establish this kind of animal experimental models, and it can simulate the ischemic state; meanwhile, the existence and extent can be showed directly by DSA, DWI, and PWI.  相似文献   
114.
Cooking processes that gelatinize granules or disrupt structure might increase the glucose and insulin responses because a disruption of the structure of starch by gelatinization increases its availability for digestion and absorption in the small intestine. We hypothesized that the uncooked form of rice, which has a relatively low degree of gelatinization even though in powder form, would result in lower metabolic glucose and insulin responses compared with cooked rice (CR). To assess the effects of the gelatinization of rice on metabolic response of glucose and insulin, we investigated the glucose and insulin responses to 3 rice meals of different gelatinization degree in female college students (n = 12): CR (76.9% gelatinized), uncooked rice powder (UP; 3.5% gelatinized), and uncooked freeze-dried rice powder (UFP; 5.4% gelatinized). Uncooked rice powders (UP and UFP) induced lower glucose and insulin responses compared with CR. The relatively low gelatinization degree of UPs resulted in low metabolic responses in terms of the glycemic index (CR: 72.4% vs UP: 49.7%, UFP: 59.8%) and insulin index (CR: 94.8% vs UP: 74.4%, UFP: 68.0%). In summary, UPs that were less gelatinized than CR induced low postprandial glucose and insulin responses.  相似文献   
115.
早期新生儿黄疸的动态监测及早期干预治疗效果评价   总被引:2,自引:2,他引:0  
目的观察出生1周内新生儿黄疸的动态变化、高胆红素血症患儿病因分析及早期干预治疗的效果。方法利用经皮胆红素测定仪对我院产科出生的928例新生儿每日进行同一部位的皮肤测定,根据新生儿不同出生情况对超过胆红素值安全范围的及时给予口服药物或转儿科蓝光治疗。结果928例新生儿因高胆红素血症住院156例,高胆红素血症发生率为15.74%,无1例发生胆红素脑病。结论对新生儿黄疸进行监测和早期干预治疗,可大幅度降低高胆红素血症的发病率,从而防止胆红素脑病的发生。  相似文献   
116.
Twist在胃癌中的表达及其与临床病理学指标关系研究   总被引:2,自引:1,他引:1  
目的:检测Twist蛋白在胃癌组织中的表达及与临床病理学指标的关系,探讨Twist蛋白在胃癌诊治中的临床应用价值。方法:应用鼠抗人Twist单克隆抗体免疫组织化学方法检测98例不同类型胃癌组织及32例正常胃组织中Twist的表达。结果:在98例胃癌组织中,Twist阳性表达60例(61.2%);在正常胃组织中其阳性表达5例(15.2%),两者比较,P=0.000(X^2=20.06);结合临床病理资料统计分析发现,Twist在胃癌组织中表达与肿瘤的分化程度、胃壁浸润、淋巴结转移及远处转移有关(X^2分别为6.577、9.557、9.87、4.88,P值分别为0.01、0.002、0.002、0.027);而其表达与病人年龄、性别无关(X^2分别为0.226、0.331,P值分别为0.634、0.565)。结论:Twist在胃癌诊断中作用明确,并且在判断肿瘤分化程度、浸润、淋巴结转移等方面均具有较好的辅助诊断价值。  相似文献   
117.
目的 探讨经尿道前列腺电气化切除术(TUVP)治疗前列腺增生症(BPH)的有效性、安全性和远期效果。方法 312例BPH患者进行TUVP手术。术前以及术后3﹑6﹑12﹑24 m分别进行IPSS﹑QOL评分﹑尿流动力学﹑剩余尿量测定。301例(96 .47%)随访资料完整。结果 术后24月IPSS评分从26.52减少至6.1 (P<0.05);QOL评分也从5.32下降至1 .47 (P<0.05);最大尿流率(Qmax)增加明显,从7.6ml/s增至18.3ml/s(P<0.05);平均尿流率(AFR)从3 .4ml/s增至9.89ml/s;排尿量(VV)较前亦有所增加(P>0.05),尤以排尿等待时间(DT) 缩短,从61s减少至5.2s,剩余尿量(RU)从98.3ml减少至13.4ml(P<0.01)。结论 TUVP是一种易于掌握、出血量少、安全性高的治疗BPH的手术方法,远期疗效肯定。  相似文献   
118.
本文介绍了42例室性心动过速的临床资料和特点,讨论了早期后除极与室性心动过速的关系,并探讨各型室速的治疗。  相似文献   
119.
术后镇痛10年后的质量控制探讨:1168例回顾性研究   总被引:1,自引:0,他引:1  
目的 了解术后镇痛的现状,探讨术后镇痛的质量控制问题。方法 回顾近3个月1168例术后镇痛所采用的镇痛方法和预防术后恶心呕吐的方法,了解镇痛效果和副作用的发生情况,并分析影响镇痛效果和副作用发生率的有关因素,患者的满意度情况。结果 90%采用了连续硬膜外镇痛法,配方主要是小剂量吗啡复合低浓度布比卡因或罗比卡因,静脉镇痛主要采用吗啡复合氯诺昔康。预防术后恶心呕吐(PONV)的方法有5-HT3受体拮抗剂(昂丹司琼或阿扎司琼),氟哌啶,地塞米松等,单用或复合应用。连续硬膜外镇痛需要补救镇痛者约5%,静脉镇痛补救镇痛者约10%。PONV总体发生率低,妇科开腹手术低至20%,女性非妇科手术低至10%,剖宫产术低至1%,使用氟哌啶使妇科手术PONV降低约50%。1例高龄患者出现血氧饱和度下降至82%,经停药、吸氧等处理好转。硬膜外导管脱落0.5%。瘙痒、头晕等并发症小于5%。通过补救镇痛,及时处理并发症,患者满意度在90%以上。结论 硬膜外镇痛方法效果优于静脉镇痛方法,适度镇痛,减少镇痛药量,增加安全性,重视PONV的预防,及时处理镇痛不足和副作用,从而提高患者的满意度,是术后镇痛质量控制的可行的理念和方法。  相似文献   
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