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Pacemaker and defibrillator leads and central venous catheters placed by commonly recommended techniques have been found to pass through the subclavius muscle, the costocaracoid ligament, or the costoclavicular ligament before entering veins medial to the first rib. Entrapment by these soft tissues subjects leads and catheters to stresses imposed by movements of the ipsilateral upper extremity. Accordingly, a new approach has been developed that introduces the lead or catheter into the subciavian vein near the lateral border of the first rib. This placement avoids soft tissue entrapment and may extend the longevity of leads and catheters.  相似文献   
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During 1988 and 1989 a survey was conducted of the drinkinghabits and alcohol-related beliefs of a national sample of teenagersin England. Data were obtained from 6,244 respondents virtuallyall aged 14–16. Heavy drinkers were significantly morelikely to report drinking in a mixed sex group than were otherteenagers. They were also more likely than others to have drunkillegally in licensed premises, and were distinctive from otherteenagers in relation to their self-reported reasons for drinkingand their alcohol-related beliefs.  相似文献   
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O to Z Reconstruction of Central Upper Lip Defect   总被引:1,自引:0,他引:1  
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Objective To develop and test a quantitative food frequency method for administration by telephone.Design A comparison study of telephone and face-to-face interviews was conducted among a representative sample of the five major ethnic groups in Oahu, Hawaii. Two interviews were administered 4 to 6 months apart by trained interviewers using identical questionnaires and color photographs of food items showing three different portion sizes. The order of the interviewing methods was randomly assigned. The questionnaire included 115 food items selected to estimate 80% or more of usual dietary intakes. Frequencies and quantities of each item consumed during the past year were obtained.Subjects/setting Subjects were recruited from the Health Surveillance Program of the Hawaii State Department of Health and consisted of 167 men and 158 women, aged 45 to 74 years, who provided a telephone number. Eighty percent of the face-to-face interviews were conducted in the subjects’ homes and 20% were conducted at the workplace or the University of Hawaii Cancer Research Center, if requested.Statistical analyses The paired t test was used to compare the mean daily intakes obtained by the telephone and face-to-face methods. Agreement was measured by the intraclass correlation coefficient (ICC), Pearson correlation coefficient, and weighted κ statistic.Results The means of energy and each nutrient were slightly higher in the first interview than the second, regardless of the interviewing method. Because of close correspondence among all 3 statistical measures of agreement, only the ICCs are reported. The ICCs ranged from .61 for protein and vitamin A to .69 for dietary cholesterol among men, and from .61 for vitamin C to .74 for saturated fat among women. Agreement was not significantly affected by age, gender, ethnicity, order of interview, or educational level.Applications Telephone interviews to obtain quantitative food frequencies are cost-efficient methods for estimating usual dietary intakes among persons in widely scattered geographic areas. Photographs of the foods in 3 portion sizes mailed in advance help the respondents estimate amounts eaten. J Am Diet Assoc. 1998;98:44-48.  相似文献   
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The Effects of Perfluorodecanoic Acid on Hepatic Stearoyl-CoenzymeA Desaturase and Mixed Function Oxidase Activities in Rats.VANRAFELGHAM, M. J., AND ANDERSON, M. E. (1988). Fundam. Appl.Toxicol. 11, 503-510. Perfluorodecanoic acid (PFDA) causes adioxin-lilce toxic syndrome and alters the hepatic oleate/stearateratio in rats. The acute toxic effects of a single ip dose (50mg/kg) of PFDA on hepatic stearoyl-CoA desaturase and mixedfunction oxidases were studied in male Fischer-344 rats, 14days after dosing. PFDA causes a marked decrease in food intakein rats, resulting in severe body weight loss with delayed lethality(2-3 weeks after dosing). To distinguish the effects of hypophagiafrom those caused by PFDA, pair-fed control rats were used inaddition to ad libitum-fed controls. Stearoyl-CoA desaturaseactivity, responsible for the conversion of stearoyl-CoA tooleoyl-CoA, was absent in both PFDA dosed rats and their pair-fedcontrols at Day 14. Electron transfer through the desaturasesystem was significantly reduced in PFDA-treated rats only,and in these rats there was a significant reduction in microsomalcytochrome an important component of this electron transfersystem. Pentobarbital sleeping times were significantly prolongedin both the PFDA-dosed and pairfed rats, as compared with thead libitumfed controls. This effect was more pronounced in PFDA-dosedrats. Waking plasma pentobarbital concentration was similarin all treatment groups. Hepatic microsomal cytochrome PASOcontent was unaffected. Aminopyrine N-de-methylase activitywas greatly reduced in PFDA-dosed rats. Although pairfed controlsalso had reduced demethylase activity, it was not as pronouncedas in PFDA-dosed rats, and was probably due to the fasted conditionof these animals. Although the mechanism of action of PFDA isnot known, it is possible that PFDA affects microsomal enzymesby altering the structure and/or function of the membranes inwhich they are located, through effects on lipid metabolism.  相似文献   
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