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91.
Ionizing radiation is a carcinogen that induces oxidative DNA damage. 8-
Hydroxy-2'-deoxyguanosine (8-OHdG) is a relatively abundant, mutagenic
lesion that is widely regarded as a reliable index of oxidative DNA damage.
The purpose of this study was to examine the effects of X- radiation on
levels of 8-OHdG in the context of an experimental model for breast cancer
in which chronic radiation exposure has been shown to be carcinogenic in
Sprague-Dawley rats. A secondary objective of this study was to determine
if the use of phenol during DNA isolation affected the concentration of
8-OHdG subsequently measured. Our results indicate that a profoundly
carcinogenic dose of radiation induced a small but significant increase in
8-OHdG concentration in mammary gland DNA, and that the use of a
phenol-based versus a salt-based method of DNA isolation had no significant
impact on the levels of 8-OHdG detected in either control or irradiated
tissue.
相似文献
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Msika S Iannelli A Marano A Zeitoun G Deroide G Kianmanesh R Flamant Y Hay JM 《Annales de chirurgie》2000,125(5):439-443
STUDY OBJECTIVE: Laparoscopic colectomies have been recently shown to be feasible and safe, with the use of stapling devices to fashion the anastomosis. The aim of this study was to evaluate the feasibility and safety of laparoscopic intra-abdominal hand-sewn anastomosis. PATIENTS AND METHODS: Seven patients (four males and three females, mean age 48 years) were included. There were two ileocolic resections for recurrence of Crohn's disease, two right colectomies (one for Crohn's disease and one for carcinoid tumor of the appendix), two left colectomies for diverticulitis and one segmental colectomy for sigmoid volvulus. There were: four side-to-side anastomoses, two side-to-end anastomoses and one end-to-end anastomosis. Anastomoses were fashioned with interrupted single layer sutures in four cases (two ileo-colic and two colorectal anastomoses) and with single layer running sutures in three cases (two ileo-colic and one colo-colic anastomoses). The specimens were retrieved by means of a plastic bag through a 3 to 5 cm long minilaparotomy in five cases and through the rectum in two cases. RESULTS: Mean additional time to perform hand-sewn intra-corporeal anastomosis was 90 +/- 15 min. There was no operative mortality and no intraoperative complications. Postoperative course was uneventful in six patients. Patients were started on an oral fluid diet on day 2 and discharged on day 5, except for one patient with Crohn's disease who had a severe anastomotic bleeding on postoperative day 2 and who required laparotomy for hemostasis through a service colotomy with a single suture. He was discharged on day 8. CONCLUSION: Intra-abdominal hand-sewn anastomoses are feasible and seem reliable. This represents a new step making laparoscopic procedures even closer to conventional techniques. This technique must be evaluated in larger series. 相似文献
94.
金银花药材中抗呼吸道病毒感染的咖啡酰奎宁酸类成分的定量研究 总被引:7,自引:3,他引:7
目的:寻找金银花中的抗呼吸道病毒感染的成分,并进行定量研究。方法:采用各种柱层析和制备薄层层析等方法分离、细胞病变法进行抗病毒作用的研究,采用RP-HPLC方法进行定量方法的研究。结果:分离得到了13种咖啡酰奎宁酸类化合物和咖啡酸、咖啡酸甲酯,确认咖啡酰奎宁酸类成分具有较强的抗呼吸道病毒作用,并采用HPLC方法测定了金银花中的 6种咖啡酰奎宁酸类成分和咖啡酸的含量。结论:咖啡酰奎宁酸类成分为金银花中的有效成分,定量方法准确、重复性好。 相似文献
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Smita C. Banerjee Thomas A. D’Agostino Mallorie L. Gordon Jennifer L. Hay 《Health communication》2018,33(2):188-201
Cancer survivors narrate their experiences in unique ways, articulating different aspects of the cancer journey. The purpose of this study was to analyze the content of cancer narratives that melanoma survivors share online in order to present the ways that survivors narrate their cancer experience, to identify survivors’ motivations for sharing, and to better understand the ways in which survivors are impacted by and cope with the diagnosis and treatment of cancer. The sample consisted of 95 unique melanoma survivor narratives, accessed from the Melanoma Research Foundation in November 2015, that were inductively and deductively coded for key themes and subthemes. Emergent themes described different aspects of the melanoma experience during prediagnosis (identification of self-phenotype, searching for causes, suspicious findings, delay in diagnosis), diagnosis (communication of diagnosis, emotional responses), transition from diagnosis to beginning treatment (second opinion), treatment (positive reframing of attitude, proactive cancer management, side effects), and posttreatment phases (social support, vigilance behaviors posttreatment). Two themes that cut across all phases of the cancer journey included recognizing and dealing with uncertainty and survivors’ motive for sharing narrative. These findings have implications for understanding how melanoma survivors may benefit personally from sharing their cancer experience online and for the potential for survivor narratives to motivate behavior change and facilitate coping among readers. 相似文献