短发卡RNA对人胃癌细胞STAT3基因的沉默作用

目的:探讨STAT3基因小发夹RNA（shRNA）表达质粒对胃癌MKN-45细胞STAT3基因的干扰作用。方法:根据STAT3 mRNA 编码序列，设计RNA干扰靶点，构建STAT3基因的特异性小RNA干扰质粒（psiRNA-H1/STAT3），使用脂质体转染人胃癌细胞系（MKN-45细胞）。实验分为对照（A）组，psiRNA-H1转染（B）组和psiRNA-H1/STAT3转染（C）组。通过RT-PCR和Western Blot检测STAT3特异性小RNA干扰基因对胃癌细胞STAT3基因mRNA和蛋白表达的影响。结果:psiRNA-H1/STAT3经限制性酶切及部分序列分析证明基因插入正确，并经测序证实。将其成功转染MKN-45细胞后，该细胞的STAT3 mRNA和蛋白表达均明显下降(P<0.05)。 结论:将成功构建的针对STAT3基因的shRNA表达载体转染MKN-45细胞，能有效抑制该细胞的STAT3 mRNA和蛋白表达，为STAT3基因靶向治疗提供一定的实验依据。     

PRL-3 miRNA重组慢病毒对胃癌SGC7901细胞增殖的抑制作用

目的 观察PRL-3在人胃癌SGC7901细胞增殖中的作用.方法 构建表达人工PRL-3 miRNA的慢病毒载体,转染SGC7901细胞,并检测其沉默PRL-3表达的效果;MTT试验评价沉默PRL-3表达对SGC7901细胞增殖的抑制作用.结果 成功构建表达PRL-3慢病毒载体.PRL-3慢病毒转染组,可沉默SGC7901细胞PRL-3的表达.MTT试验结果,沉默PRL-3的表达后,与空载体组比较,SGC7901细胞数下降了30.4%;生长曲线比较,SGC7901细胞的增殖受到明显抑制(P＜0.05).结论 PRL-3在胃癌生长中起着重要作用,可作为胃癌潜在的治疗靶点.     

Tiam 1与胃癌细胞侵袭转移及与裸鼠移植瘤形成的关系

摘要：目的 检测胃癌细胞中T淋巴瘤侵袭转移诱导因子 1(Tiam 1)的表达，并分析其与胃癌细胞离体、在体侵袭转移能力的关系。方法 采用层粘连蛋白黏附法，由胃癌MKN 45细胞株(M0)中筛选获得高(MH)、低(ML)黏附亚株。应用RT PCR和定量细胞ELISA技术分别检测Tiam 1 mRNA与蛋白在M0，ML，MH细胞中的表达；应用Boyden小室法测定M0，ML，MH细胞的离体侵袭移行能力，并分析其与Tiam 1表达的关系。应用裸鼠接种法观察M0，ML，MH细胞的在体成瘤及转移能力。结果 MH细胞中Tiam 1 mRNA(RV=0.855±0.051)与蛋白的表达(RD=1.262±0.165)以及其离体侵袭转移能力(24.33±8.02，52.00±14.53)、在体裸鼠肺转移率(4/5=80%)均较M0细胞(RV=0.759±0.047，RD=0.911±0.104，11.67±3.79，26.00±9.54，2/5=40%)，ML细胞(RV=0.743±0.039，RD=0.892±0.101，9.67±3.06，23.67±8.50，1/5=20%)为强，统计学差异显著(P< 0.05)，但在M0，ML细胞间无统计学差异(P> 0.05)；Tiam 1表达水平与胃癌细胞的侵袭转移能力呈完全及高度正相关(P< 0.05)。结论 Tiam 1表达水平升高有可能促进胃癌细胞侵袭转移能力的增强。     

内镜活检对胃癌组织学分类术前诊断的价值

目的 探讨内镜活检对胃癌组织学分类术前诊断的价值。方法 术前对141例胃癌患的内镜活检标本分别根据Lauren分类和世界卫生组织（WHO）分类判断组织学分类，并与手术标本结果对照。结果 内镜活检对胃癌Lauren分类术前诊断的准确率为76.6%。对肠型胃癌诊断的敏感性和特异性分别为85.4%和80.6%。而对弥漫型胃癌则分别为82.7%和80.3%，在59例术前诊断为肠型胃癌的病例中，18例（30.5%)在手术标本中呈弥漫性行生长，而在75例术前诊断为弥漫型胃癌的病例中，仅6例（8.0%)术后诊断为肠型胃癌，内镜活检对胃癌WHO分类术前诊断的准确率为87.2%，其中对乳头状/管状腺癌，黏液腺癌和印戒细胞癌的敏感性分别为91.9%。33.3%和66.7%。结论 内镜活检对胃癌组织学分类的术前诊断具有较高的临床应用价值。     

腹腔镜辅助胃底贲门癌根治术：附22例报告

目的探讨腹腔镜辅助下行D2式胃底贲门癌根治术的临床效果。方法回顾性分析3年间行腹腔镜辅助下胃底贲门癌根治术22例患者的临床资料。全组均行腹腔镜辅助下近端胃大部切除术。结果无中转开腹,平均手术时间188(162~270)min。术中平均出血182(100~260)mL。淋巴结清扫18.6(10~32)枚。术后患者平均胃肠道功能恢复时间78(48~140)h。1例肿瘤侵犯食管下段的患者术后发生吻合口瘘,经留置空肠营养管、抗炎、充分引流等处理后4周痊愈。无手术死亡。全组术后随访1~37个月,平均9.2个月,无复发转移病例。结论腹腔镜辅助下行D2式胃底贲门癌根治术方法可行,效果好,具有视野清晰、创伤小、出血少、恢复快等优点。     

20例胃平滑肌肿瘤的病理-X线分析

为了提高对胃平滑肌肿瘤的认识,作者回顾性分析了20例经手术、病理证实的胃平滑肌肿瘤的钡餐造影所见。结果表明,胃底与胃体上部是胃平滑肌肿瘤的病变高发区。本病具有典型胃粘膜下肿瘤的X线特征,腔内型者可见胃内边缘光滑的充盈缺损或软组织肿块,粘膜展平或推移;腔外型者可见突出胃外肿块或/和胃与邻近脏器受压;腔内外型者具有上述双重特征,肿瘤较大者多有溃疡形成,甚至囊变,根据肿瘤的大小、形态、生长类型及溃疡表现可作良恶性鉴别。本病的术前诊断主要依靠X线钡餐检查,但无胃肠压迫的腔外型肿瘤,钡餐则难以发现,CT或选择性血管造影可助诊断。     

Developmental changes in intracellular pH buffering power in smooth muscle

 Intracellular pH (pH_i) is known to modulate contraction. Neonatal tissues can differ from adult tissue in contractile response to stimuli known to alter pH_i e.g. hypoxia. Changes of pH are attenuated by buffering, thus any difference in buffering power (β) between tissues could affect their functional response to pH_i perturbation. Similarly the extent to which any extracellular pH (pH_o) alteration is transmitted into a pH_i change will also influence function. We have therefore determined the intrinsic β and effect of pH_o change on pH_i in neonatal and adult ureteric, uterine and gastric smooth muscles using the pH-sensitive fluorophore carboxy-SNARF. β was found to be similar in the three adult tissues, but there were significant differences between neonatal tissues. In contrast, we found little difference in the amount of pH_i change produced by pH_o change between neonatal and adult tissues from the same smooth muscle, but a difference between smooth muscles. These data highlight significant differences between smooth muscles and their developmental state, which may contribute to different degrees of protection when pH is perturbed. Received: 17 October 1997 / Received after revision: 27 November 1997 / Accepted: 28 November 1997     

胃前壁癌肿在双对比造影中的影像特征(附35例分析)

目的：通过分析胃前壁癌肿在双对比造影（DC）中的X线征象，提高对其影像特征的认识。方法：复查分析经术前、手术和病理证实，均做了DC的胃前壁癌肿35例。结果：悬滴、白雾状影、重叠白线及线征4个征象的出现率分别达78％、94％、66％、88％。当癌肿累及大小弯侧时，还可出现腔壁多边征。如能确定上述征象中的1、2个对诊断有重要意义。结论：胃前壁癌肿在DC中有其特征性的影像表现，注意观察并充分认识上述征象及其周围组织结构的变化，并紧密结合临床综合分析，有助于提高术前诊断的准确性。     

Nodular sarcoidosis of the liver and spleen: Appearance on MR images

Small nodular lesions in the liver and spleen have been reported as an infrequent manifestation of sarcoidosis. Five patients with this appearance on either dynamic contrast material—enhanced computed tomographic (CT) or ultrasound scans underwent magnetic resonance (MR) imaging with and without dynamic gadolinium enhancement. The lesions were relatively uniform in size, ranging from 0.5 to 1.5 cm. On CT scans, they were hypoattenuating relative to surrounding parenchyma. On MR images, the lesions were hypointense relative to background parenchyma with all sequences. No substantial enhancement was observed in the lesions, although lesion conspicuity decreased over time on serial postcontrast images. Lesion conspicuity was greatest on either T2-weighted fat-suppressed (T2FS) images or early-phase dynamic contrast-enhanced images. Abdominal adenopathy was seen in three of the five patients and was hyperintense relative to liver on T2FS images in two and intermediate in intensity in one patient.     

Splenic nonenhancement at computed tomography: A sign of the hypoperfusion complex

When splenic nonenhancement is seen at computed tomography, one should look for signs of vascular pedicle injury; if injury to the vascular pedicle is not present, nonenhancement of the spleen could be secondary to severe vasoconstriction and may be considered an additional sign of the hypoperfusion complex. The presence of splenic nonenhancement may also help differentiate the hypoperfusion complex from other types of bowel injury.