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21.
神经再生素对皮层细胞基因表达影响的基因芯片研究   总被引:6,自引:0,他引:6  
目的:采用基因芯片技术,观察神经再生素对体外培养的胚鼠大脑皮质细胞基因表达的影响。方法:取ICR胚鼠(15d)大脑皮层细胞,无血清培养。实验组加入神经再生素(2μg/ml),对照组加入等量基础培养液。培养6h后,抽提实验组和对照组皮层细胞总RNA,经反转录分别用Cy5、Cy3荧光标记成cDNA探针。将荧光标记的cDNA与MGEC-40s基因表达谱芯片杂交,芯片扫描、数据处理。结果:实验组与对照组大脑皮质细胞出现64条差异性表达的基因。呈现上调的基因有:钙调素结合蛋白、锌指蛋白激酶、核糖体蛋白等基因;下调基因有:抑制细胞分裂因子等基因。结论:神经再生素可作用于体外培养的胚鼠大脑皮层细胞,从基因调控水平促进脑细胞生长。  相似文献   
22.
This report evaluates the possibility that atmospheric iodine (I) can make a significant contribution to I nutrition and concludes that the combustion of gas and oil can increase atmospheric H. Sedimentation treatment of water supplies extracts some I from raw water, and sewage plants concentrate I and return it to the environment via sewage effluent. The I cycle in nature is discussed, and it is concluded that minute amounts of I usually are present in the atmosphere but are not usually in significant enough amounts to contribute substantially to bodily I requirements.  相似文献   
23.
目的 研究99Tcm TRODAT 1在正常猴及帕金森病 (PD)模型猴纹状体内的放射性分布 ,以探讨其早期诊断PD的价值。方法 分别对 2只正常猴、2只PD模型猴进行99Tcm TRODAT 1多巴胺转运蛋白 (DAT)显像 ,1只经 1 甲基 4苯基 1,2 ,3 ,6 四氢吡啶 (MPTP)预处理后行 7、11、18d连续显像 ;计算正常猴与PD模型猴纹状体与小脑放射性比值。结果 正常猴 3h纹状体与小脑的放射性比值为 1 5 6;PD模型猴损毁侧纹状体与小脑比值为 0 94 ,健侧为 1 5 2 ;MPTP预处理后 7d与正常猴比值相似 ,11d时下降 ,18d时明显降低 ,比值分别为 1 5 6、1 2 7、0 89。结论 99Tcm TRODAT 1能特异性地与DAT结合 ,可灵敏地反映PD模型猴DAT的摄取减少 ,对PD的早期诊断有一定的临床价值。  相似文献   
24.
Pancreaticoduodenectomy combined with portal vein resection is increasingly accepted as a viable treatment option for pancreatic carcinoma with suspected involvement of the portal vein.However, its clinical benefit remains controversial. This study evaluated the outcomes of pancreaticoduodenectomy with portal vein resection for pancreatic carcinoma in a group of Chinese patients operated on by a specialized team in a center with a low case volume of pancreatic cancer. The perioperative and long-term outcomes of 12 patients with portal vein resection for suspected involvement of the portal vein and 38 patients who underwent pancreaticoduodenectomy without portal vein resection during the same period were compared. In the former group, eight patients underwent segmental resection, and four patients underwent wedge resection of the portal vein. There were no significant differences in operative blood loss (median 0.8 vs. 0.8 liter, p = 0.313), hospital mortality (0% vs. 2.6%, p = 1.000), or operative morbidity (41.7% vs. 42.1%, p = 0.979) between the two groups. Patients who required portal vein resection had higher frequencies of microscopic lymphatic permeation (58.3% vs. 18.4%, p = 0.023) and vascular invasion (50.0% vs. 15.8%, p = 0.025). Long-term survival was comparable between patients with portal vein resection and those without it (median 19.5 vs. 20.7 months, p = 0.769). These findings suggest that pancreaticoduodenectomy combined with portal vein resection can be performed safely by a specialized team in a center with a low case volume of pancreatic carcinoma and that it may offer survival benefit in patients with suspected portal vein involvement.  相似文献   
25.
BACKGROUND: The diagnosis of graft-versus-host disease (GvHD) after liver transplantation can be difficult because early symptoms are often nonspecific. In this study, the presence of donor lymphocyte macrochimerism in recipient peripheral blood was examined as a diagnostic aid for GvHD after cadaveric donor liver transplantation. METHODS: Between 1996 and 2002, 33 liver transplant recipients with a clinical suspicion of GvHD (skin rash, diarrhea, pyrexia, pancytopenia, or anemia, without an obvious alternative cause) were investigated for peripheral blood donor lymphocyte macrochimerism. Donor macrochimerism was determined at the time of first clinical presentation by a low-sensitivity polymerase chain reaction (PCR) to detect donor human leukocyte antigen (HLA) alleles using genomic DNA extracted from recipient peripheral blood. Where donor HLA alleles were detected, the percentage of donor T cells was quantified by two-color flow cytometric analysis using antibodies specific for mismatched donor and recipient HLA alleles. The relationship between the presence or absence of donor lymphocyte macrochimerism and final diagnoses based on clinical and histological criteria was examined. RESULTS: Seven of the 33 patients were PCR positive for donor HLA alleles. All had macrochimerism, with donor T lymphocyte levels ranging from 4% to 50% of circulating lymphocytes. All seven patients had normal liver function tests, skin rash, and diagnosis of GvHD histologically confirmed by skin or gut biopsies. Twenty-six patients were PCR negative, and, in 23, an alternative diagnosis was eventually established. The remaining three patients made a rapid and spontaneous recovery with no further symptoms suggestive of GvHD. CONCLUSIONS: Donor lymphocyte macrochimerism was present in all patients in whom the diagnosis of GvHD was confirmed. In patients with symptoms consistent with GvHD and a negative PCR for donor HLA, an alternative diagnosis was eventually established or the patients recovered spontaneously. Detection of donor HLA alleles in recipient peripheral blood by PCR is a useful diagnostic tool for GvHD after liver transplantation.  相似文献   
26.
目的 体外观察巨噬细胞(M)对血管内皮细胞同源盒(HOX)B2基因mRNA和血管内皮生长因子(VEGF)受体KDRmRNA及整合素ανβ3表达的影响。 方法 体外培养人脐静脉血管内皮细胞系ECV304,分为(1)ECV304组; (2)ECV304 伴刀豆球蛋白A(conA,终浓度25mg/L)组; (3)ECV304 人M系U937组:ECV304细胞中加入1×105 /mlU937细胞; (4)ECV304 U937 conA组:ECV304中加入1×105 /mlU937细胞及终浓度25mg/L的conA.反应48h后,用免疫荧光技术检测各组ECV304细胞整合素ανβ3的表达情况,并用逆转录聚合酶链反应(RT PCR)技术检测细胞KDRmRNA和HOXB2基因mRNA的表达水平。 结果 ECV304组细胞的整合素ανβ3、KDRmRNA及HOXB2基因mRNA的表达水平分别为6. 7±1. 5、0. 633±0. 012、0. 674±0. 004。ECV304 U937 conA组细胞上述指标较ECV304组均明显上调(P<0. 01 ),分别为10. 2±1. 7、0. 879±0 003、0. 947±0 003。其余两组细胞上述指标与ECV304组比较,差异均无统计学意义(P>0. 05).结论 被conA活化的M通过影响内皮细胞的KDRmRNA、HOXB2mRNA基因及整合素ανβ3的表达,来促进内皮细胞增殖、迁移及与基质黏附,从而调节血管生成。  相似文献   
27.
<正> Objective:To examine the action of the effective component,4'-methylether-scutellarein,from Verbena officinalis L.(VOL)on the proliferation and apoptosis of human choriocarcinomaJAR cells.Methods:Cell proliferation was measured by MTT[3-(4,5-dimethylthiazol-2-yl)-2,5-di-phenyl tetrasodium bromide,MTT]assay and the incorporation of tritiated thymidine(~3H-TdR).Apoptosis of cell was evaluated by flow cytometry(FCM)and the characteristic apoptoticDNA ladder by agarose gel electrophoresis,and the morphological changes of apoptotic JAR cellswere observed under fluorescence microscopy and electron microscopy(EM).Expressions of ap-optosis proteins,poly(ADP-ribose)polymerase(PARP)and caspase-3,-8,and -9 were deter-mined with Western blot.Results:The effective component from VOL inhibited the proliferation of JAR cells in a dose-and time-dependent manner.The treated cell cycle was arrested in S phase and an apoptotic peakwas found in S phase using FCM analysis.A typical DNA ladder appeared in the treatment groupwhen analyzed by agarose gel electrophoresis.Using fluorescence microscopy,the percentage ofapoptotic cell was 0.9%,6%,and 14% after treatments of 10,20,and 40 mg·L~(-1) of the effec-tive component,respectively,for 48 h.Typical apoptotic changes,such as condensed chromatinand presence of apoptotic bodies,were observed under EM.Treatment with effective componentfor 48 h and 72 h also induced protein expression of PARP and caspase-3,-8,and -9 as seen byWestern blot.Conclusions:The effective component from VOL inhibits cell proliferation and induces apop-tosis in human choriocarcinoma JAR cells.  相似文献   
28.
目的:构建小鼠髓样相关蛋白14(MRP14)的真核表达载体,观察其在NIH3T3细胞中的表达定位情况。方法:提取BALB/c小鼠肝脏组织的总RNA,通过逆转录-聚合酶链反应(RT-PCR)扩增得到MRP14编码序列。然后将该编码序列克隆到带有血凝素(HA)标记的载体pcDNA3-HA上,随后转染NIH3T3细胞,在荧光显微镜下观察结果。结果:重组质粒经聚合酶链反应(PCR)、酶切和测序鉴定证明构建正确。转染实验发现,该质粒能够在NIH3T3细胞中表达,表达产物主要定位在细胞质中。结论:成功构建带HA标签的MRP14真核表达载体。该载体能在哺乳动物细胞中有效表达并正确定位,为下一步深入研究MRP14作用细胞的信号通路提供了一个重要工具。  相似文献   
29.
Endoscopic extraperitoneal inguinal hernioplasty has been gaining in popularity worldwide recently. Placement of mesh remains a technically challenging part of the procedure. This paper describes a systematic method for the placement of mesh during endoscopic inguinal hernioplasty. To broaden the endoscopic view and maximize working space, the mesh should be kept far from the telescope within the limited extraperitoneal space. Unfolding the mesh requires prior stabilization of the mesh at one point, to avoid uncontrolled migration of the whole mesh and subsequent loss of mesh orientation. Mastering the skill of two‐handed technique is essential for coordinated manipulation and expeditious mesh placement. Before concluding the procedure, a trial of deflation can help to ensure appropriate repositioning of the peritoneum without displacement of the mesh. Chinese Abstract
Figure Chinese Abstract Open in figure viewer PowerPoint

Volume 6 , Issue 1 February 2002

Pages 18-21  相似文献   

30.
目的 采用反向Fick氏法和间接测热法测定心脏手术后病人的全身氧耗,并比较两种测量方法的相关性和准确性。方法8例心脏手术术后病人,分别在入ICU后2h和6h时同时采用反向Fick氏和间接测热法测定病人的全身氧耗量。结果 间接测热法和反向Fick法测得氧耗分别是(16±30)ml·min-1·m-2和(127±23)ml·min-1·m-2,前者的测定结果显著高于后者(P<0.01)。相关分析显示两者有较好的相关性(r=0.92,P<0.01)。采用Bland和Altman统计分析提示两种测定结果的平均偏离值为(35.5±13.4)ml·min-1·m-2,其95%的分布范围是(9~62)ml·min-1·m-2,提示两种测量结果间的一致性较差。结论 两种方法测定心脏病人术后全身氧耗的结果有明显差异,其中反向Fick氏法的测定结果误差大、准确性差,而间接测热法是较好的临床选择。  相似文献   
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