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61.
Ultrasonography in the detection of cervical incompetency 总被引:2,自引:0,他引:2
Mario Podobnik Milan Buli Nikola Smiljanic Josip Bistri
ki 《Journal of clinical ultrasound : JCU》1988,16(6):383-391
In 80 pregnancies with clinical and ultrasonic signs of cervical incompetency, the length of the cervix and the thickness of the anterior wall of a lower uterine segment have been evaluated ultrasonically. We have also measured the width of the endocervical canal and studied the prolapse of fetal membranes (with fetal parts) into the endocervical canal. We evaluated these same parameters in 80 healthy pregnancies. The length of the cervix, the thickness of the anterior wall of a lower uterine segment, and the width of the endocervical canal were followed longitudinally in the patients from the 10th to the 36th gestation week. No statistically significant differences between age groups were found. In four age groups at risk for cervical incompetency, cervical lengths and wall thickness were significantly different (p less than 0.001) from those in comparable controls. Forty-five percent of the patients in the at-risk group, with cervical cerclage, delivered at 37.3 (range: 32 to 41) weeks and 6.25% of pregnancies ended in abortion when the amniotic membrane herniated into the cervical canal, with or without some part of the fetus. 相似文献
62.
E. Van de Keift K. De Boulle P. Willems J. -J. Martin P. Selosse B. Van der Auwera 《Acta neurochirurgica》1992,117(3-4):172-177
Summary Inactivation of tumour suppressor genes or anti-oncogenes as well as activation of dominant acting oncogenes seem to be important mechanisms in the pathogenesis of gliomas. We compared constitutional and tumoural genotypes at different restriction fragment length polymorphism loci (RFLP) on chromosomes 10 and 17 in 15 unrelated individualsLoss of heterozygosity (LOH) pointing to chromosomal loss or deletions was detected for at least one chromosme 17 marker in 11 gliomas (astrocytomas grades I–III and glioblastoma multiforme), whereas LOH for chromosome 10 loci was only detected in 3 out of 9 cases of glioblastoma multiforme and was not detected in low grade gliomas. Since LOH for chromosome 10 loci seems to be restricted only to glioblastoma multiforme, it is possible that recessive mutations on chromosome 10 are engaged in tumour progression from astrocytomas to glioblastoma multiforme. As LOH of chromosome 17 markers occurs in astrocytomas as in glioblastoma multiforme, chromosome 17 loci probably are involved in early tumour development. 相似文献
63.
采用20~200U/ml的重组人肿瘤坏死因子(rhTNF-α)处理体外液相培养的人早幼粒白血病细胞珠HL-60,观察到50~200U/ml的小剂量TNF具有诱导其向单核-巨噬细胞途径分化及抑制其增殖的效应。采用细胞总RNA打点杂交技术检测1~100U/mlTNF诱导HL-60细胞早期(12小时内)对其c-myc,c-fos原癌基因表达的影响,发现TNF可抑制c-mycmRNA水平及c-fos短暂性表达增高。结果表明此小剂量rhTNF-α具有诱导白血病细胞分化的效应及调控多癌基因表达的作用。 相似文献
64.
目的研究全肝MR灌注成像(MRPI)早期监视兔肝VX2瘤经皮酒精注射(PEI)疗效的价值。方法新西兰大白兔10只,经开腹手术于肝内注射VX2肿瘤细胞悬液0.1ml,分别在种瘤后第2、3周进行MRT。WI、T2WI检查监视肿瘤生长情况。在种瘤后第3周时,于CT引导下,于肿瘤一侧的早期强化最明显处注射无水乙醇1.0ml,治疗1周后应用MRPI观察治疗效果。灌注参数包括:对比剂到达时间(T0)和最大上升斜率(ss),应用t检验比较治疗区与肿瘤未治疗区的灌注参数。结果10只兔肿瘤均种植成功,第3周时肿瘤直径(2.6±0.6)cm。治疗过程中3只兔死亡,PEI治疗1周后的治疗区呈无或低度强化。肿瘤未治区与治疗区的11D分别为(16.0±1.2)、(50,8±5.9)S,ss分别为38.9±2.2、6.0±1.2,差异均有统计学意义(t值分别为15.8、-39.6,P值均〈0.05)。常规T1 WI、T2 WI无法清晰显示治疗区与未治疗区的差异。结论全肝MRPI可以较敏感的早期监测PEI疗效,早期强化的消失可作为PEI治疗有效的标志。 相似文献
65.
66.
pp32表达引起人肝癌细胞HepG2形态改变 总被引:1,自引:1,他引:0
目的:研究pp32在肝癌细胞中的作用.方法:采用RT-PCR的方法钓取pp32全长基因.脂质体介导的方法将pp32基因导入HepG2细胞.观察细胞形态,血清依赖性和接触抑制等细胞表型,测量细胞生长曲线,检测ALP、LDH、γ- GT、ALB和AFP等生化指标.结果:成功钓取了pp32全长基因,筛选获得pp32稳定表达的HepG2细胞株.pp32表达使HepG2细胞伸出细长突起,但不影响HepG2细胞增殖.ALP和LDH酶活力升高,其他指标没有变化.结论:pp32表达引起人肝癌细胞HepG2形态改变,但不改变其恶性表型. 相似文献
67.
Susanna L. Matsen Charles J. Yeo Ralph H. Hruban Michael A. Choti 《Journal of gastrointestinal surgery》2005,9(2):270-279
Humoral hypercalcemia of malignancy is widely associated with tumor production of parathyroid hormone related protein (PTH-rP).
This peptide functions in endocrine, autocrine and paracrine mechanisms in a manner similar to PTH; increasing renal uptake
of calcium, decreasing retention of phosphorous, and stimulating adenylate cyclase and phospholipase C. Although PTH-rP production
has been well documented in neoplasms of the exocrine pancreas, we present here two cases of endocrine pancreatic neoplasms
elaborating PTH-rP. We then review the literature of previous cases and delve into the pathophysiology of this peptide. 相似文献
68.
Malignant peripheral nerve sheath tumors (MPNST) are defined as any tumor arising from a peripheral nerve or showing nerve
sheath differentiation. The majority of these tumors arise on the trunk, extremities, or head and neck region. The literature
to date has fewer than 14 cases of MPNST arising in the gastrointestinal tract, and only two cases were ever reported in the
small intestine, one of which was a recurrent disease. In this paper, we report the first US case of an MPNST arising in the
small intestine and presenting as intussusception. 相似文献
69.
经肝动脉灌注三氧化二砷对肝移植瘤血管的作用 总被引:5,自引:0,他引:5
目的 :探讨经肝动脉灌注As2 O3 对肝移植瘤血管的作用 .方法 :采用新西兰大白兔建立 5 0只肝脏Vx 2移植瘤动物模型 ,随机平均分成 5组 .移植瘤术后 2wk ,经肝动脉插管灌注不同浓度As2 O3 ,并以顺铂和生理盐水作对照 ,连续 7d ,6wk末切取肝肿瘤组织 ,观察肿瘤组织微血管有无改变 ,检测移植瘤组织血管内皮生长因子 (VEGF)的表达 .结果 :实验组肿瘤组织毛细血管内皮细胞肿胀、细胞核碎裂、细胞坏死及微血栓形成 ,阴性对照组和阳性对照组无类似改变 .实验组VEGF表达低于对照组 ,差异有显著性 (P <0 .0 1 ) ,而实验组间VEGF表达无差异性 (P =1 .0 0 ) .结论 :经肝动脉灌注As2 O3可减少肿瘤组织的血管生成 ;选择性破坏肝移植瘤组织血管 ,并存在一定剂量效应相关性 相似文献
70.
Shuichiro Uchiyama Kazuo Chijiiwa Masahide Hiyoshi Motoaki Nagano Jiro Ohuchida Koki Nagaike Masahiro Kai Kazuhiro Kondo 《Journal of gastrointestinal surgery》2007,11(11):1570-1572
Mucin-producing tumor in the bile duct is referred to clinically as mucin-producing bile duct tumor (MPBT). Intraductal papillary
neoplasm of the biliary tract that resembles an intraductal papillary mucinous neoplasm (IPMN) of the pancreas is a rare category
of MPBT and is not well characterized. We, herein, report a case of MPBT of the caudate lobe of the liver that showed papillary
growth and communicated with the bile duct of the caudate lobe and protruded into the common hepatic duct. Histologically,
MPBT cells showed papillary overgrowth with abundant mucinous secretions, resembling an IPMN of the pancreas. The MPBT cells
showed the same immunostaining pattern as that of cells from IPMN of the pancreas. 相似文献