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51.
从大鼠肝分离出小分子蛋白质,注入肝大部切除的大鼠体内。术后24h制备肝细胞悬液及骨髓细胞悬液,用流式细胞计测定细胞DNA含量。结果:①实验组大鼠每克体重注入肝提取物10~300μg,一致呈现4n肝细胞DNA复制受阻于G_1期,各类肝细胞数与正常大鼠的相似;②对照组大鼠,4n肝细胞由正常的68.1%降至30.9%,8n肝细胞由6.3%骤增至25.3%,并出现16.8%的4n~8n间8期肝细胞;③两组大鼠的骨髓细胞DNA含量均无变化。表明肝提取物中含有肝抑素样物质,它特异性地使再生肝的4n肝细胞增殖周期阻滞于G_1期及S早期。  相似文献   
52.
Hepatic angiomyolipoma is a rare tumor composed of spindle-shaped and epithelioid smooth muscle cells, adipose tissue, and proliferating blood vessels. We report the first documented case of this tumor developing in a patient with ulcerative colitis. A solitary tumor (7.5×7.5×7cm) was detected in the left lateral segment of the liver and a left hepatic lobectomy was performed. The diagnosis of angiomyolipoma was confirmed by a pathological examination. We also review the literature on previously reported cases of hepatic angiomyolipoma.  相似文献   
53.
Chlordecone (CD) pretreatment is known to markedly potentiate CCl4 hepatotoxicity. Previous studies have shown that prior exposure to CD obtunds the increased hepatocellular regeneration and repair observed in non-treated rats challenged with a single, low dose of CCl4. These observations allowed us to hypothesize that suppression of hepatic regeneration and tissue repair by CD + CCl4 combination treatment might be involved in this interaction. To test this hypothesis, CCl4 hepatotoxicity was evaluated in actively regenerating livers using CD-treated (10 ppm in the diet for 15 days), surgically partially hepatectomized (PH) male Sprague-Dawley rats. Rats undergoing no surgical manipulation (CTRL) and sham operation (SH) were included as appropriate controls. Surgical manipulations were conducted on day 15 of the dietary protocol. Based on liver-to-body weight ratios (LW/BW), mitotic indices, hepatic cytochrome P-450 content, and hepatic glutathione (GSH and GSSG) levels, PH-induced hepatocellular regeneration was not affected by pretreatment with CD. Thus, the PH model was considered valid for assessing the effects of CD + CCl4 combination treatment. CCl4 (100 l/kg; i.p.) was administered 1, 2, 4 or 7 days after the surgical manipulations. Hepatotoxicity was assessed 24 h later by measuring LW/BW and serum enzymes (SGPT, SGOT and ICD) in all four groups. Hepatic histopathological, histomorphometric and lethal effects were assessed in animals receiving CCl4 1 or 7 days after the surgical manipulations. CCl4-induced increases in LW/BW were observed in CD + PH rats receiving CCl4 4 or 7 days post-PH, but not in the 1 or 2 day post-PH groups in which the hepatocellular regeneration was maximal. CCl4-induced serum enzyme elevations were significantly less in the CD + PH rats as compared to CD + SH. This decrease in the serum enzyme elevations was most prominent in the 1 day post-PH group, where the hepatocellular mitotic activity was most pronounced. CCl4 lethality, assessed in the 1 day post-surgical manipulation group, was also decreased in the CD + PH rats in comparison to CD + SH rats. Such a protection was not observed in rats receiving CCl4 7 days post-PH. These data are consistent with and are supportive of the hypothesis that a suppression of otherwise normally stimulated hepatocellular regeneration following low-dose CCl4 administration is involved in the marked amplification of CCl4 toxicity by CD.Abbreviations CD chlordecone - GSH reduced glutathione - GSSG oxidized glutathione - PH partial hepatectomy - SH shamhepatectomy - CTRL control, not surgically manipulated - N normal diet - LW/BW liver weight-to-body weight ratio - SGPT serum glutamic; pyruvic transaminase - SGOT serum glutamic oxaloacetic transaminase - ICD isocitrate dehydrogenase These studies were made possible by a grant from the US Environmental Protection Agency R-811072A preliminary report of these findings was presented at the 70th Annual Meetings of the Federation of American Societies for Experimental Biology at St. Louis, MO (Fed Proc 45: 1051, 1986)A. N. Bell is a Predoctoral Toxicology Trainee and Robert A. Young is a Postdoctoral Trainee supported by Toxicology Training grant from National Institute of Environmental Health Science ES-07045  相似文献   
54.
目的:探讨超声造影(CEUS)技术在腹腔镜T1期肝细胞癌(HCC)切除术中的应用价值。方法:选择2018年1月—2020年12月于天津医科大学第二医院行腹腔镜T1期HCC切除术的患者80例,根据是否行术前CEUS将患者分为造影组和对照组(每组40例)。均在距肿瘤边缘0.5 cm处切开患者肝脏实质并完整切除肿瘤,然后在切缘3个不同位置取组织活检。采用免疫组化检测癌组织中增殖细胞核抗原(PCNA)及Bcl-2相关X蛋白(Bax)的表达水平。记录患者手术时间、术中出血量、住院时间、肿瘤直径、切缘长度、术后进食时间、拔除引流管时间、术后最高丙氨酸氨基转移酶(ALT)和总胆红素(TBIL)及其恢复正常时间。术后均行规律随访观察。结果:与对照组相比,造影组手术时间(t=11.69,P<0.001)及住院时间更短(t=9.40,P<0.001),术中出血量更少(t=14.86,P<0.001);而两组患者在肿瘤直径(t=0.28,P=0.78)、切缘长度(t=0.18,P=0.86)、术后进食时间(t=0.44,P=0.66)及拔除引流管时间(t=1.16,P=0.25)方面差异均...  相似文献   
55.
目的 分析经皮射频消融(PRFA)与手术切除治疗直径≤3 cm原发性小肝癌的疗效。方法 选取2015年1月—2017年6月兰州市第二人民医院收治的原发性小肝癌患者78例。将36例接受PRFA治疗的患者作为观察组,另外42例行手术切除的患者作为对照组。采用全自动生化分析仪检测血清谷草转氨酶(AST)、谷丙转氨酶(ALT)、总胆红素(TBIL)水平,电化学发光全自动免疫分析仪检测血清甲胎蛋白(AFP)水平。结果 观察组手术时间、术中出血量、住院时间均少于对照组(P <0.05);观察组治疗前后AST、ALT、TBIL、AFP的差值均高于对照组组(P <0.05)。两组术后并发症比较,差异无统计学意义(P>0.05);两组治疗后1、2、3、5年的生存率和复发率比较,差异均无统计学意义(P>0.05)。结论 与手术切除比较,PRFA治疗直径≤3 cm原发性小肝癌可缩短手术时间,减少术中出血量,促进肝功能恢复,但两者术后并发症发生率、生存率和复发率接近。  相似文献   
56.
部分背根切断对备用背根节NT-3表达的影响   总被引:1,自引:0,他引:1  
目的 探讨部分去背根后备用背根节 (L6 )各类细胞NT 3及其mRNA的含量变化。 方法 对成年雄性猫行单侧部分背根切断术 (切除一侧L1 ~L5,L7~S2 DRG ,保留L6 为备用根 )。取正常组一侧和术后 3d及 7d组手术侧的L6 DRG制作 2 0 μm厚冰冻切片 ,分别用NT 3抗体及NT 3cRNA探针行免疫组织化学及原位杂交染色。观察NT 3及其mRNA在DRG各类细胞的分布 ,测定NT 3及其mRNA在神经元和卫星细胞的光密度值 ,所得数据用q检验进行统计分析。 结果 部分去背根后 ,各时相备用背根节大神经元内NT 3的光密度值较正常者进行性减少 ,(P <0 0 5 ) ,而NT 3mRNA的光密度值术后 3d减少 ,7d回升至近正常者水平。比较之 ,小神经元和卫星细胞NT 3及其mRNA的光密度值进行性增多 (P <0 0 5 )。 结论 部分背根切断对备用背根节各类细胞NT 3表达的影响不同 ,其功能意义可能与NT 3参与脊髓Ⅱ板层可塑性有关  相似文献   
57.
Abnormality of chromosome 16 and its phenotypic expression   总被引:2,自引:0,他引:2  
An abnormality of chromosome 16 in which there is extra genetic material present on the short arm (46, XY, 16p+) has been identified. This chromosomal aberration was associated with multiple congenital anomalies, including mid-facial hypoplasia, arthrogryposis, and mental retardation. On the basis of the cytogenetic appearance and the phenotype of the patient, this may represent a partial 16 trisomy. Unlike most abnormalities of chromosome 16, this syndrome was compatible with life.  相似文献   
58.
Partial left ventriculectomy (PLV) was originally introduced as a new surgical approach by patients with an end stage of cardiac disease. Coronary artery bypass grafting (CABG) is a standard procedures used in cardiac surgery. Multichannel ECG (MECG) measurements and body surface mapping (BSM) were used to analyse the normalised beat amplitude power maps (BAM) that reflect an overall cardiac activity. The resulting BAMs show that the amplitude of cardiac signals decrease for approximately 30% after the PLV and stay in the same level during the postoperative monitoring interval while after CABG no significant changes in BAM have been observed. In addition the electrodes from the body surface area above the left ventricle, where surgery was performed, show significant changes in beat amplitudes.  相似文献   
59.
目的了解糖类代谢相关基因在大鼠肝再生中的表达变化。方法本研究用搜集网站资料和查阅相关论文等方法获得糖类代谢相关基因,用大鼠基因组230 2.0芯片检测它们在大鼠再生肝中的表达情况,用比较手术组和假手术组中基因表达的差异性确定肝再生相关基因。结果初步证实上述基因中118个基因与肝再生相关。肝再生早期[部分肝切除(PH)后0.5~4h]、前期(PH后4~12h)、中期(PH后16~66h)和后期(PH后72~168h)等4个阶段起始表达的基因数为33、6、68和7;基因的总表达次数为68、44、210和83。表明肝再生相关基因主要在肝再生启动阶段起始表达,在不同阶段发挥作用。它们共上调205次,下调200次,分为12种表达方式,表明肝再生中糖代谢活动多样和复杂。其中,单糖和糖原代谢、糖蛋白和糖脂(主要为神经节苷脂)合成相关基因几乎在整个肝再生中表达增强,寡糖和糖胺聚糖合成及糖蛋白和糖脂分解相关基因表达下调。结论肝再生与糖代谢密切相关。  相似文献   
60.
Two thirds of the liver was removed from (CBA×C57BL/6j)F1 female mice. On the 5th day after the operation a significant increase was observed in the number of endogenous colonies in the spleen of the partially hepatectomized animals. This increase was not connected with a change in the number of stem cells in the bone marrow, for partial hepatectomy at different times after the operation did not affect the number of colony-forming units in the bone marrow.Laboratory of Virology, Oncologic Scientific Center, Academy of Medical Sciences of the USSR, Moscow. (Presented by Academician of the Academy of Medical Sciences of the USSR N. A. Kraevskii.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 85, No. 2, pp. 218–219, February, 1978.  相似文献   
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