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61.
Transforming growth factor-β1 (TGF-β1) is known to be a potent growth inhibitor for many cell types, including most epithelial cells. In skin keratinocytes, TGF-β1 has been shown to inhibit growth and to rapidly reduce c-mycexpression. However, the molecular mechanism of TGF-β1 action on cell growth of cervical carcinoma has not yet been elucidated. We thus assessed the effect of TGF-β1 on the growth of cervical carcinoma cell lines. Two cervical squamous carcinoma cell lines, CUMC-3 and CUMC-6, were incubated with varying concentrations of TGF-β1, and growth inhibition was evaluated with tetrazolium-based colorimetric assay. After culture in TGF-β1 for 24 h, inhibition of growth was detected in a dose-dependent manner at concentrations of 0.1–10 ng/ml in both cell lines. This effect of TGF-β1 on cultured carcinoma cells was associated with apoptotic process including oligonucleosomal ladder DNA and apoptotic body formations. Northern blot analysis revealed c-mycmRNA expression was suppressed by 10 ng/ml of TGF-β1 following 3 h of treatment in both cell lines. Western blot analysis showed that the level of p27Kip1protein was increased after TGF-β1 treatment in both cell lines. These results suggest that the mechanisms by which TGF-β1 inhibits the growth of cervical carcinoma are complex and may include effects on down-regulation of c-mycgene, and overexpression of p27Kip1protein.  相似文献   
62.
The aim of this study was to evaluate if intraoperative vascular ultrasonography is of clinical value in the perioperative management of hepatic transplant patients. Fifteen intraoperative ultrasonographic examinations were performed on 13 patients (five female, eight male) during transplantation. These patients had clinically suspected vascular compromise. Among the 13 patients studied intraoperatively, five were correctly diagnosed as having hemodynamically significant vascular compromise. Of the intraoperative vascular sonographic examinations, the results of 13 were in concordance with the surgical impression as to whether further intervention was necessary or if the procedure could be terminated. Intraoperative sonography demonstrates potential to be of aid to the surgeon in recognition of vascular compromise.  相似文献   
63.
We describe a novel human zinc finger cNDA, C2H2-171. This cDNA represents an mRNA which encodes a protein of 484 amino acids and a calculated molecular weight of 54 kD. Four zinc finger-like domains are found in the C-terminal end of the protein. At the N-terminus, C2H2-171 contains a POZ/tramtrack-like domain similar to that found in the tumor associated zinc finger proteins LAZ-3/BCL-6 and PLZ-F, as well as in non-zinc finger proteins. C2H2-171 RNA is preferentially expressed in the brain, and increases during the course of murine development, with maximal expression in the adult. C2H2-171 RNA is differentially expressed in brain regions, with the highest level of expression in the cerebellum. C2H2-171 RNA was expressed at high levels in primary cerebellar granule cell neurons compared to astrocytes. The gene encoding C2H2-171 is highly conserved in vertebrates, and maps to the terminus of human chromosome 1 (1q44-ter). This chromosomal location is associated with a number of cytogenetic aberrations including those involving brain developmental anomalies and tumorigenesis. These data suggest that C2H2-171 may play an important role in vertebrate brain development and function.  相似文献   
64.
65.
关于单结合胆红素水溶性的研究   总被引:4,自引:0,他引:4  
目的:进一步研究单结合胆红素(MCB)的水难溶特性及其在病理性胆汁中参与胆红素沉淀和色素性结石形成的作用机制.方法:应用胆红素高效液相色谱分析技术,先从人胆汁中获得结合胆红素,再经分离、制备及纯化得到纯MCB.然后观察其水溶解度并与其它型胆红素比较.结果:在pH7.9,温度37℃接近生理的条件下,MCB的溶解度(558.25±5.96μm)仅为双结合胆红素(DCB)的1/7,比不结合胆红素(UCB)高约44倍并随pH值改变而呈曲线变化.pH7.9时最大;pH4.5时为0;而当pH>9时,反而低于呈离于状态的UCB.结论:MCB虽作为结合型胆红素在胆道生理条件下的不溶性明显高于UCB,但比DCB要低得多;而在胆道病理条件下,其水溶性不但远低于DCB,甚至还不如离子化的UCB,这可能是MCB参与胆红素沉淀及胆色素结石形成的理化基础.  相似文献   
66.
67.
Twenty-eight patients participated prospectively in a study to evaluate the impact of hysteroscopically detected uterine and cervical anomalies on the success rate of ET in an IVF-ET program. All participants had a normal intrauterine cavity by standard HSG. All the patients had a diagnostic office hysteroscopy under paracervical block before commencing COH. Because our IVF program does not include hysteroscopy as a requirement before undergoing IVF and because the significance of mild intrauterine abnormalities is not yet known, the hysteroscopic findings were not relayed to the personnel involved in the IVF-ET procedure. Sixteen patients (group I) had a normal hysteroscopic evaluation. Twelve patients (group II) had abnormal hysteroscopic findings including small uterine septa, small submucous fibroids, uterine hypoplasia and cervical ridges. Although no difference in patients or cycle characteristics was present, there was a significant difference in the clinical PR between patients in groups I and II. In conclusion, in an IVF-ET program patients with normal hysterography but abnormal hysteroscopic findings had a significantly lower clinical PR, demonstrating the importance of performing hysteroscopy before IVF-ET.  相似文献   
68.
A nephritic condition was developed by infecting Swiss Webster albino mice with the malarial parasite Plasmodium berghei NK 65. These animals were tested for urinary protein and the presence of circulating immune complexes using reagent strips and a polyethylene glycol (PEG) precipitation assay. The circulating immune complexes were isolated from the sera using both affinity chromatography and PEG precipitation and from the kidney by acid elution. The isolated complexes were dissociated into their individual components and analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). The components of the complexes were transferred to nitrocellulose sheets and probed for the presence of malarial antigens using a rabbit anti-P berghei antisera. The overall humoral response to the malarial parasite was evaluated using a radial immunodiffusion assay. The present study confirmed that the malarial-infected animals not only developed the nephritic condition (as evident by the high levels of proteinuria) but also, as indicated by the PEG assay, have the presence of high levels of circulating immune complexes in their serum. The apparent absence in the SDS gels of any abnormal protein bands followed by the inability of the Western blot to reveal any malarial antigens provides some of the strongest evidence to date that these malarial proteins are not directly involved in the circulating immune complexes believed to be responsible for producing this nephritic condition.  相似文献   
69.
The standard semen analysis frequently fails to identify subfertile males even when findings are normal and conversely often fails to identify fertile males with subnormal semen analyses. This has created the need to produce other tests of sperm physiology that will better distinguish a fertile from a subfertile specimen. Understanding more about the nature of the sperm defect should lead to the establishment of more specific and effective therapies. Until that time, it would still be reasonable to try some of the available empirical therapies even though they may work merely by a placebo mechanism.  相似文献   
70.
Gastrointestinal dysfunction among intensive care unit patients   总被引:3,自引:0,他引:3  
This study used the Acute Physiological and Chronic Health Evaluation (APACHE II) system to select two groups of ICU patients with comparable risk of hospital death to evaluate the importance of GI dysfunction, defined as failure to tolerate enteral nutrition (EN), as a prognostic factor. In our ICU, patients who have not undergone recent bowel surgery are treated by EN. Those patients who cannot tolerate EN are treated by total parenteral nutrition (TPN). One hundred and eleven patients who tolerated EN (functioning gut) and 97 TPN patients who failed to tolerate EN (GI dysfunction) were studied. The mean APACHE II scores of the two groups were 17.7 +/- 6.5 (SD) and 17.7 +/- 5.1, respectively. The observed mortality of patients with GI dysfunction (51%) was significantly higher (p less than .0005) than that of patients with a functioning gut (25%). This was associated with significantly poorer APACHE II mean BP, oxygenation, and creatinine scores among the GI dysfunction patients. Our results suggest that shock, ischemia, and hypoxemia, in addition to causing impairment of renal function, may bring about changes in the GI tract, evident clinically only as a failure to tolerate EN, which have an adverse effect on the prognosis of ICU patients so affected.  相似文献   
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