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Detection frequency of human herpesvirus 6 (HHV-6) and Epstein Barr virus (EBV) DNA in multiple sclerosis (MS) patients and controls was investigated. DNA of peripheral blood mononuclear leukocytes (PBL) was isolated and amplified by polymerase chain reaction techniques. EBV DNA was detected in all patients and controls. HHV-6 DNA was detected in 7% of MS patients and in 14% of controls. Results are compared with other investigations of HHV-6 DNA in PBL, serum, CSF and brain of patients with MS. Results of the present study and other investigations do not show an association between HHV-6 in PBL and MS. Multiple Sclerosis (2000) 6, 66 - 68  相似文献   
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Electrogustometry is well established as a clinical tool for the estimation of taste detection thresholds. Nevertheless, the user is sometimes unaware of the impact of superficially minor procedural and psychophysical factors upon the reliability and comparability of threshold estimates. The inherent strengths and limitations of the procedure are outlined, and aspects of the control and specification of the stimulus that moderate threshold measures are discussed. In addition, threshold estimates from two individuals with severe unilateral taste loss are used to illustrate the level at which anodal dc current may elicit common, rather than taste, sensation. Where chorda tympani section is complete and historical (older than 7–14 days), very high stimulus levels, conservatively over 5 µA/mm2 (100 µA linear current with a 5‐mm diameter electrode), are required to activate trigeminal responses.  相似文献   
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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   
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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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