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71.
目的:观察麝香保心丸(SXBXW)对内皮素-1(ET-1)诱导原代培养的人脐动脉血管平滑肌细胞(VSMCs)增殖作用的影响。方法:建立ET-1刺激原代培养人脐动脉VSMCs增殖的细胞模型,设对照组、ET-1组、ET-1+SXBXW0.25g/L组、ET-1+SXBXW0.5g/L组、ET-1+SXBXW1.0g/L组和ET-1+SXBXW2.0g/L组,采用MTT法测定ET-1和SXBXW对细胞增殖的影响;用台盼蓝拒染和乳酸脱氢酶检测方法观察不同浓度的SXBXW对VSMCs的毒性作用;用流式细胞术观察ET-1和SXBXW对VSMCs增殖周期的影响。结果:与对照组相比,ET-1可显著促进VSMCs的增殖,一定剂量的SXBXW能够有效地抑制ET-1诱导的VSMCs细胞增殖,呈剂量依赖性;SXBXW抑制细胞增殖,但对活细胞数目和乳酸脱氢酶释放量均没有影响,提示对VSMCs无毒性作用。ET-1能够刺激VSMCs从G1期进入S期,从而促进细胞增殖,而SXBXW能抑制这一作用。结论:SXBXW能够有效抑制ET-1诱导的VSMCs增殖作用,其作用机制可能与其抑制细胞周期从G1期进入S期有关。  相似文献   
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 目的 探讨颈椎手术中并发椎动脉损伤的发生原因、治疗及预防。方法 回顾性分析2002年10月至2012年4月颈椎手术中并发椎动脉损伤的7例患者资料,男6例,女1例;年龄23~65岁,平均48.9岁;脊髓型颈椎病5例,颈椎外伤合并C4,5半脱位1例,氟骨症致颈椎管狭窄1例。椎动脉损伤均为单侧,左侧4例,右侧3例。分析颈椎手术中并发椎动脉损伤的原因、处理过程及预后。结果颈椎前路手术4例,其中2例用环钻减压时偏离中线损伤椎动脉,1例切除椎间盘时刮匙过于偏外损伤椎动脉,1例颈椎外伤患者由于C4,5半脱位造成椎动脉迂曲,减压时冲击式咬骨钳损伤椎动脉。颈椎后路手术3例,其中2例为行C4侧块螺钉固定时钻头偏外损伤椎动脉;1例氟骨症致颈椎管狭窄者在切除寰椎后弓时咬骨钳损伤椎动脉,术中出现椎动脉损伤后,迅速填塞压迫止血并关闭伤口,但术后4周发生迟发性出血,采用椎动脉栓塞止血及颈后路血肿清除术治疗。7例患者均未发生脑梗塞,其中2例患者术后出现一过性头晕。结论 椎动脉损伤是颈椎手术的严重并发症,其损伤原因与手术失误、解剖变异等有关;采用直接压迫及椎动脉栓塞治疗效果确切。  相似文献   
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BACKGROUND/AIMS: Liver failure is a life threatening condition currently treated by palliative measures and, when applicable, organ transplantation. The use of a bioartificial organ capable of fulfilling the main functions of the liver would represent an attractive alternative. However, the shortage of suitable donor cells, and their limited growth ability have impeded the development of this strategy. We investigated whether lentiviral vectors allow for conditional immortalization of human hepatocytes and whether these immortalized hepatocytes could reverse lethal acute liver failure. METHODS: We exposed primary human hepatocytes to Cre-excisable lentiviral vectors coding for SV40T Antigen, telomerase, and/or Bmi-1 and tested the functionality of the resulting cell lines. Therapeutic potential of immortalized hepatocytes were tested in a murine model of acetaminophen-induced hepatic injury. RESULTS: The immortalized hepatocytes grew continuously yet were non-tumorigenic, stopped proliferating when exposed to Cre recombinase, and conserved defining properties of primary hepatocytes, including the ability to secrete liver-specific proteins and to detoxify drugs. The implantation of encapsulated immortalized human hepatocytes rescued mice from lethal doses of acetaminophen. CONCLUSIONS: Lentiviral vectors represent tools of choice for immortalization of non-dividing primary cells, and lentivirally immortalized human hepatocytes are promising reagents for cell-based therapy of acute liver failure.  相似文献   
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Rationale:Acutefatty liver of pregnancy (AFLP) is a potentially fatal obstetric emergency characterized by acute hepatic failure secondary to fatty infiltration. The resultant effects include coagulopathy, electrolyte abnormalities, and multisystem organ dysfunction. Pancreatitis typically develops after the onset of renal and hepatic dysfunction. Pancreatitis has been suggested as a poor prognostic indicator because it is associated with more adverse outcomes.Patient concerns:A 29-year-old Chinese woman at 34.7 weeks pregnancy was admitted to hospital due to paroxysmal hypogastric pain and massive colporrhagia for 1 day.Diagnosis:Laboratory tests revealed hepatic and renal impairment, coagulopathy. Thoracoabdominal computed tomography (CT) scanning showed pleural and peritoneal effusion, fatty liver, and pancreatitis. She was diagnosed with AFLP, severe acute pancreatitis (SAP), multiple organ dysfunction syndrome (MODS), and intrauterine fetal death.Interventions:The patient was treated with blood component transfusions, plasma exchange combined with renal replacement therapy, antibiotic de-escalation, gastric and pancreatic secretion inhibitor, and enteral nutrition.Outcomes:After successful management, the patient was discharged without any complications on day 35 of admission. At 10 months follow-up, thoracoabdominal enhanced CT revealed was normal and laboratory tests revealed normal liver and kidney function.Lessons:Once AFLP is highly suspected or confirmed, the pregnancy should be terminated in time and active symptomatic management should be given.  相似文献   
77.
The etiology of dental-supporting tissue diseases in children is multi factorial and not merely related to oral hygiene. Therefore, in the present study, we investigated the relationship between children <18 years old with allergic rhinitis (AR) and the risk of dental-supporting tissue diseases.Data from the National Health Insurance Research Database (NHIRD) of Taiwan were used to conduct a retrospective longitudinal cohort study. The study cohort comprised 378,160 patients with AR (AR group) and 378,160 patients without AR (non-AR group), who were selected through frequency matching based on age, sex, and the index year. The study patients were followed until dental-supporting tissue diseases occurrence, withdrawal from the National Health Insurance program, or December 31, 2013. Cox proportional hazards regression analysis was conducted to calculate the risk of dental-supporting tissue diseases in the AR group after adjustment for age, sex, and relative comorbidities.The adjusted HRs of periodontal, pulp, and periapical diseases in AR children were higher than those in the non-AR controls (1.51, 95% CI: 1.50 to 1.53; 1.06, 95% CI: 1.05 to 1.07, respectively). The AR to non-AR HRs of these inflammatory dental diseases were particularly higher in children <6 years old and in boys. The HRs of periodontal, pulp, and periapical diseases were greatest in those with >5 AR-related medical visits/year (5.57, 95% CI: 5.50 to 5.56; 4.06, 95% CI: 4.00 to 4.12, respectively).Children with AR had a greater risk of inflammatory dental-supporting tissue diseases, particularly those <6 years old with primary teeth, boys, and those with severe persistent AR.  相似文献   
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