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To elucidate the global distribution and toxicological impacts of polychlorinated biphenyls (PCBs) on cetaceans, the present study determined the concentrations of individual PCB congeners, including toxic non-ortho (IUPAC Nos. 77, 126, 169) and mono-ortho (IUPAC Nos. 105, 118, 156) coplanar congeners, in the blubber of 10 species of adult male odontocetes collected from several locations in the North Pacific Ocean and along coastal waters of Japan, Hong Kong, the Philippines, and India during 1985–1997. Total PCB concentrations in cetaceans from temperate and cold waters were higher than those in cetaceans from tropical regions. Residue levels were found to be the highest in Fraser's dolphins collected off Kii Peninsula, Japan, and hump-backed dolphins from Hong Kong, reflecting serious marine pollution by PCBs in industrialized Asian countries. Penta- and hexa-chlorobiphenyls were the predominant PCB congeners, accounting for about 70% of the total PCBs. 2,3,7,8-Tetrachlorodibenzo-p-dioxin equivalents (TEQs) of non- and mono-ortho coplanar PCBs in the blubber of cetaceans ranged from 36 (in spinner dolphins from the Philippines) to 510 pg/g wet weight (in hump-backed dolphins from Hong Kong). Toxic evaluation of coplanar PCBs using the TEQ concept indicates an greater impact on cetaceans from mid-latitudes. Toxicity contribution of mono-ortho congener IUPAC 118 was prominent in species from high latitude oceans, such as the Bering Sea and the North Pacific, whereas non-ortho congener IUPAC 126 accounted for the highest contribution in cetaceans from lower latitude regions, such as the Philippines and India. The estimated TEQ concentrations in the blubber of some cetacean species, such as northern right whale dolphin and Pacific white-sided dolphin from the northern North Pacific, Dall's porpoise from the Japan Sea, striped dolphin off Sanriku and Fraser's dolphin off Kii Peninsula, Japan, hump-backed dolphin and finless porpoise from Hong Kong, exceeded the levels associated with immunosuppression in harbour seals. Received: 7 September 1999/Accepted: 3 May 2000  相似文献   
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Introduction Some patients with ICDs experience the sensation of a shock in the absence of true therapy (phantom shock). We hypothesize that phantom shocks may be a manifestation of anxiety, depression or PTSD.Methods and results All patients over 18 years old with an ICD were eligible to enroll in the study. The first 75 subjects who agreed to participate were enrolled and divided into three groups: ICD patients with phantom shocks (n = 19); ICD patients who had actual shocks (n = 28) and ICD patients who had no shocks (n = 28). During a clinic visit a demographic questionnaire and three psychological rating scales were administered: the Spielberger State–Trait Anxiety Inventory (STAI); the Center for Epidemiologic Studies Depression Scale (CES-D) and the Posttraumatic Stress Checklist (PCL-C). No significant differences between groups were found in gender, race, age, history of MI or cardiac surgery status. Data analysis of the psychological indices using one-way ANOVA showed that the group with phantom shocks had more depression (CES-D p = 0.011) and more anxiety (STAI p = 0.010) than the other groups. Multiple comparisons of group means showed a greater percentage of clinically depressed patients in the phantom shock group than in the other groups.Conclusion Patients with phantom shocks are more likely to be clinically depressed and have higher levels of anxiety than other ICD patients, regardless of history of actual shocks.This publication was partially supported by Grant number K30-AT-00060 from the National Center for Complementary and Alternative Medicine (NCCAM). Its contents are solely the responsibility of the authors and do not necessarily represent the officicial views of the NCCAM or the National Institutes of Health.  相似文献   
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OBJECTIVE: To establish a method of implantation for device leads across total venous occlusions. BACKGROUND: Indications for pacemaker and implantable cardiac defibrillator implantation continue to expand. Chronic venous occlusions are increasingly encountered with lead placement. Some degree of obstruction can be as high as 13% before device implantation and 50% after transvenous device implantation. We report an approach of venoplasty/dilatation of chronic total occlusions to allow lead placement. METHODS: From January 1, 2002 through December 16, 2004, 1,356 systems (initial and upgrade) were implanted at the University of Virginia. At the time of device implant, seven patients were noted to have chronic venous occlusions and alternative access was precluded. Four of the seven patients had an existing system; the other three received initial implantations. Subsequently, these seven patients had a 5 Fr catheter placed in the basilic/axillary/subclavian vein and a venogram was obtained to demonstrate the area of chronic occlusion. A guide wire was advanced across the lesion for initial recanalization. Dilatation or venoplasty was performed at the occluded site. A guide wire was retained across the lesion and the patient underwent lead implantation. RESULTS: In all seven patients, recanalization was achieved and leads were successfully placed. There were no complications or damage to the vessels or existing leads. CONCLUSIONS: Venoplasty or dilatation of chronic total venous occlusion is a safe and effective technique, which allows for placement of transvenous leads.  相似文献   
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