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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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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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Data on the civil registration of all births and deaths recordedin 1987 in Belgium were analysed following WHO rules. The followingstatistics with significant regional variations were recorded:2.5% of teenage pregnancies, 7% of late pregnancies (35 years),6.1% of low birth weights and 5.3% of preterm deliveries. Pretermbirth rates did not improve during the last decade and are higherthan in neighbouring countries. Infant mortality rate is 9.74per 1000. This rate has remained unchanged since the early 1980sbut the relative importance of post-neonatal mortality is increasing.Congenital anomalies account for 26% of all infant deaths followedby the sudden infant death syndrome (17%). Maternal conditionssuch as eclampsia are related to 29% of the infants' deaths.  相似文献   
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P-selectin (also called CD62, GMP-140, PADGEM, CD62P) is a recently described member of a family of vascular adhesion receptors expressed by activated platelets and endothelial cells that are involved in leucocyte cell adhesion. The aim of this study was to characterize a new monoclonal antibody (LYP7) directed against activated human blood platelets that inhibits ristocetin-induced platelet aggregation. Immunoadsorbent affinity chromatography and immunoprecipitation studies showed that LYP7 (IgG1) bound a surface-labelled glycoprotein (GP) which changed its apparent molecular mass (Mr) on reduction from 138 kD (situated below GPIIb) to 148 kD (above GPIIbα). LYP7 and S12, a monoclonal antibody directed against P-selectin immunoprecipitated the same band. Using ELISA assay, purified P-selectin was shown to bind LYP7 and S12 monoclonal antibodies. Binding sites of 125I-labelled LYP7, which was greatly increased on thrombin-stimulated (2 U/ml) washed platelets (10825±2886, mean ±SD) (Kd=1.5±0.5 nm ) compared to resting platelets (2801±1278, mean ±SD) (Kd=1.5±0.6 nm ), was found to be normal on thrombin-stimulated platelets taken from a patient with grey platelet syndrome or a patient with Glanzmann thrombasthenia. LYP7 (IgG1, F(ab′)2 or Fab fragments) inhibited ristocetin-induced platelet aggregation of platelets in a dose-dependent fashion without affecting the binding of von Willebrand (vWf ) factor. However, agglutination of formaldehyde-fixed platelets induced by ristocetin was not affected by monoclonal antibody LYP7. In addition, the binding of thrombin-activated platelets to neutrophils was inhibited by monoclonal antibody LYP7. These results strongly suggest that P-selectin, by promoting cell–cell contact, may play an active role in platelet–platelet interactions.  相似文献   
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