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81.
82.
The effects of combined use of earthworm extract(912)and HpD-laser on the produc-tion of reactive oxygen and the biosynthesis of DNA in S_(180) tumor cells were studied throughchemiluminescence measurement and[~3H]-TdR incorporation assay.The results showed that as com-pared with the control,the intensity of chemiluminescence emitted by tumor cells treatedsimultaneously with 912 and HpD-laser was enhanced more than ten-folds,while that treated with912 or HpD-laser alone was increased only 2~4 folds.The[~3H]-TdR incorporation into tumorcells of the former group was inhibited upto 74.1%,and that of the latter groups decreased onlyby 42.2% and 40.0%,respectively.In accordance with these biochemical changes,the ultrastructuraldamage of tumor cells of the former,combinedly treated group appeared to be the most serious.This suggests an additive effect of 912 with HpD-laser on tumor cells.In addition,if free radicalscavengers,such as catalase and superoxide dismutase,were added to the reaction systembefore chemiluminescence assay,the luminescent enhancement effect mentioned above was dramaticallyalleviated,implying the presence of O_2~ and H_2O_2 in the system.Therefore,as to the toxic effecton tumor cells,912 and HpD-laser are not only additive in efficiency,but also similar in theunderlying mechanism of action. 相似文献
83.
K. SIEUNARINE P. MOXEY D.C.M. BOYLE L. UNGAR† I. LINDSAY‡ G. DEL PRIORE§ & J.R. SMITH§ 《International journal of gynecological cancer》2005,15(5):967-973
While developing the technique of abdominal radical trachelectomy for conservative cervical cancer management, the vascular supply of the uterus was thoroughly examined. The question of how many vessels the uterus requires to ensure its viability arose. Following an abdominal radical trachelectomy for stage IB cervical carcinoma, blood supply of the body of the uterus is successfully maintained by only the two infundibulopelvic vessels (n= 34). Pregnancy has resulted following this technique (n= 2). Selective ligation of the pelvic vasculature has been utilized in the abdominal radical trachelectomy procedure. The objectives of this study were to investigate the vasculature of the infundibulopelvic and broad ligaments, to assess the contribution of the ovarian and uterine vessels to overall uterine perfusion, and to consider the clinical applications of selective pelvic vessel ligation. Ten fresh dissections of the infundibulopelvic vessels, broad ligaments of benign total abdominal hysterectomy, and bilateral salpingo-oophorectomy specimens were performed. Perfusion index (PI) and oxygen saturation (O(2)Sat) measurements using a modified probe were taken at specified intervals at the uterine cornu during ten routine benign abdominal hysterectomies to assess the contribution of the ovarian and uterine vessels to overall uterine perfusion and the concepts studied were utilized in certain gynecological procedures. The ovarian/infundibulopelvic vessels course medially through the broad ligament toward the uterine cornu and consistently give off a branch to the ovary on its lateral border. In addition, further vessels were noted to run laterally from the uterine cornu along the ovarian ligament to the medial aspect of the ovary. PI and O(2)Sat measurements imply that the uterine and ovarian vessels contribute almost equally to uterine perfusion. Clinical application by selective ligation of the pelvic vasculature has been utilized in certain gynecological procedures often prone to torrential life-threatening uterine hemorrhage. Selective temporary ligation of the uterine and ovarian vessels has proven useful in the surgical management of chemoresistant gestational trophoblastic disease, in the Strassman procedure, fertility-sparing surgery in ruptured cornual ectopic pregnancies, and unrelenting postpartum hemorrhage. Of the six supplying vessels (ovarian, uterine, and vaginal) to the uterus only two (ovarian or uterine or a combination thereof) are required for uterine viability. 相似文献
84.
Shun'Ichi Abe Hiroshi Yoshimura Hideki Tabara Mitsuo Tachibana Naomi Monden Teruhisa Nakamura Saburou Nagaoka 《Journal of surgical oncology》1995,59(4):226-229
Patients with stage T3N0~2M0 gastric carcinoma (n = 108) were studied for relevant prognostic factors. Peritoneal lavage cytology (PLC) was performed in all. In univariate analysis, 5-year survival rates were better with smaller serosal invasion (diameter <3.0 cm vs. ≥3.0 cm, 61% vs. 37%, P < 0.05) and fewer metastatic nodes (≤5 vs. ≥6, 57% vs. 29%, P < 0.05). In multivariate analyses, only these two factors were significant. The predictive value of PLC was not shown in both univariate and multivariate analyses. Peritoneal recurrence occured in 14 (22%) of 77 patients with negative PLC, and in 3 (18%) of 17 with positive PLC, the difference being not significant. Our results indicate that PLC is insensitive in predicting the development of peritoneal recurrence. Its role in the estimation of survival is limited, as many will die of visceral or locoregional recurrence if not of peritoneal dissemination. 相似文献
85.
(一)表没食子儿茶素没食子酸酯对活性氧自由基的清除作用机制 总被引:2,自引:0,他引:2
本文研究了(一)表没食子儿茶素没食子 酸酯[(—)-EGCG]清除O_(?)和·OH的半数清除率SC_(50)、清除速率常数k和清除反应的化学计量因子n,用体外模型分析了药物对活性氧自由基的清除机制和(—)-EGCG自由基的启动及结构特点,推论药物的清除反应中心为B、D和A环,每分子药物可捕捉6个O_(?)或·OH,与化学计量因子n=6相符。 相似文献
86.
87.
A M Abdel Gader A A Al-Mishari S A Awadalla N M Buyuomi T Khashoggi M Al-Hakeem 《International journal of gynaecology and obstetrics》2006,95(3):248-253
OBJECTIVE: To clarify the role played by tissue factor pathway inhibitor (TFPI) in pregnancy hypertension. METHODS: Using enzyme-linked immunosorbent assays, hemostatic measurements were obtained for women with pre-eclampsia (n=51), nonproteinuric hypertension of pregnancy (n=62), postpartum pre-eclampsia 24 h after childbirth (n=31), and no hypertension (healthy pregnant controls, n=100). RESULTS: There was a significant increase in circulating free TFPI levels in women with pre-eclampsia (9.7+/-6.2 ng/mL) or nonproteinuric hypertension of pregnancy (8.3+/-5.3 ng/mL) compared with healthy controls (5.3+/-2.1 ng/mL). In women with pre-eclampsia the levels remained elevated after placental delivery (10.6+/-4.0 ng/mL). Free protein S levels were significantly higher in women with pre-eclampsia (40.0%+/-10.7%), nonproteinuric hypertension of pregnancy (37.1%+/-12.5%), or postpartum pre-eclampsia (39.3%+/-9.1%) than in healthy pregnant controls (32.2%+/-8.5%). CONCLUSION: Increased levels of the physiologically active free forms of TFPI and free protein S, 2 coagulation inhibitors, may protect women with pregnancy-induced hypertension from the risks of hemostatic activation. 相似文献
88.
影响原发性肝癌根治术后近期和远期复发的临床病理因素 总被引:2,自引:0,他引:2
目的 :探讨根治性肝癌术后近期和远期复发因素 ,以期对高复发倾向人群抗复发提出针对性对策。方法 :回顾分析 1994年 5月~ 1998年 1月 16 2例根治性肝癌切除病例的临床资料 ,以影像学发现肿瘤复发及患者死亡或末次随访日期为截点确定无瘤生存时间 ,将术后复发病人分为近期复发 (≤ 2年 )、远期复发 (>2年 )及未复发 3组 ,确定复发危险因素。结果 :本组术后 1、 3、 5年无瘤生存率分别为 6 7. 1、 4 4 . 7及 2 5 . 5 %。与肿瘤近期复发相关因素为发现方式、肿瘤大小、血管癌栓、INM分期 ;与后期复发相关因素为有无肝硬化及其类型、肝功Child -Pugh分级和有无子瘤。结论 :根治性肝癌切除术后近期和远期复发的临床病理因素不同 ,及早发现小肝癌是预防近期复发的关键 ,兼顾术前肝功能可以对远期复发有预测作用 相似文献
89.
目的 探讨局部应用抗氧化剂VitC、VitE对准分子激光屈光性角膜切削术(PRK)术后角膜组织的影响。方法 将24只实验免分成2组,每组12只,行双眼一5.0DPRK。一组术后左眼每日结膜下注射VitC0.1g,右眼为对照;另一组术后左眼每日结膜下注射VitE25mg,有眼为对照。于术后1、3、7、14天测定角膜组织超氧化物歧酶(super—oxide dismutase,SOD)、丙二醛(malondialdehyde,MDA)及谷肮甘肽过氧化物酶(glutathioneperoxNe,GSH—PX)的变化,观察其病理变化。结果 术后1、3天角膜SOD、GSH—Px活性小于对照组(P<0.01),MDA的水平高于对照组(P<0.01)。局部应用抗氧化剂组其角膜SOD、GSH—PX活性高于单纯激光组(P<0.01),MDA水平低于单纯激光组(P<0.01)。结论 准分子激光屈光性角膜切削术后,存在着氧自由基性的组织损伤破坏,局部应用VitC、VitE能降低角膜的自由基损伤。 相似文献
90.
Multicoil Dixon chemical species separation with an iterative least-squares estimation method. 总被引:1,自引:0,他引:1
Scott B Reeder Zhifei Wen Huanzhou Yu Angel R Pineda Garry E Gold Michael Markl Norbert J Pelc 《Magnetic resonance in medicine》2004,51(1):35-45
This work describes a new approach to multipoint Dixon fat-water separation that is amenable to pulse sequences that require short echo time (TE) increments, such as steady-state free precession (SSFP) and fast spin-echo (FSE) imaging. Using an iterative linear least-squares method that decomposes water and fat images from source images acquired at short TE increments, images with a high signal-to-noise ratio (SNR) and uniform separation of water and fat are obtained. This algorithm extends to multicoil reconstruction with minimal additional complexity. Examples of single- and multicoil fat-water decompositions are shown from source images acquired at both 1.5T and 3.0T. Examples in the knee, ankle, pelvis, abdomen, and heart are shown, using FSE, SSFP, and spoiled gradient-echo (SPGR) pulse sequences. The algorithm was applied to systems with multiple chemical species, and an example of water-fat-silicone separation is shown. An analysis of the noise performance of this method is described, and methods to improve noise performance through multicoil acquisition and field map smoothing are discussed. 相似文献