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As a means for assessing cardiac function, electrical field plethysmography (EFP) has been shown to have some features quite different from electrical impedance plethysmography (EIP). Here the two techniques are compared by using the two systems simultaneously on a subject and also with independent use in different electrode configurations. The results conform with the view that EIP is related primarily to volumetric changes of the aorta, whereas EFP is affected predominantly by changes in cardiac dimensions and orientation. Because of this difference, the standard time differential formula used for EIP is not applicable for the computation of cardiac output from the EFP waveforms. An alternative method of computation based on the amplitude of the EFP waveform is suggested.  相似文献   
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Trio exome sequencing is a powerful tool in the molecular investigation of monogenic disorders and provides an incremental diagnostic yield over proband‐only sequencing, mainly due to the rapid identification of de novo disease‐causing variants. However, heterozygous variants inherited from unaffected parents may be inadvertently dismissed, although multiple explanations are available for such scenarios including mosaicism in the parent, incomplete penetrance, imprinting, or skewed X‐inactivation. We report three probands, in which a pathogenic or likely pathogenic variant was identified upon exome sequencing, yet was inherited from an unaffected parent. Segregation of the variants (in NOTCH1, PHF6, and SOX10) in the grandparent generation revealed that the variant was de novo in each case. Additionally, one proband had skewed X‐inactivation. We discuss the possible genetic mechanism in each case, and urge caution in data interpretation of exome sequencing data. We illustrate the utility of expanding segregation studies to the grandparent generation and demonstrate the impact on exome interpretation strategies, by showing that objective genotype data can overcome subjective parental report of lack of symptoms.  相似文献   
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Purpose: Our purpose was to measure changes in semen quality and quantity in young healthy sperm donors in Jerusalem over time. Methods: A retrospective analysis of semen parameters over 15 years using linear regression analysis, in a single sperm bank in a tertiary university center. Study population consisted of 188 young, healthy medical students, aged 20 to 30 years, who donated sperm samples for Artificial insemination between 1980 and 1995. Results: There were no statistically significant changes in semen concentration and motility during the study period. The mean semen volume increased by 0.1 ml (5.1%) per year (P < 0.0001), with a concomitant mean rise of 5.8 × 106 (7.7%) per year in total motile sperm count. The percentage normal morphology decreased by a mean of 1.04% per year during the entire period (P < 0.0001). Conclusions: During the past 15 years, there has been an increase in total motile sperm count, secondary to an increase in semen volume, and a decline in normal morphology that are independent of the age and the duration of abstinence in fertile men.  相似文献   
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Coeliac trunk (CT) is a ventral branch of abdominal aorta (AA) supplying the foregut through its three main branches, left gastric (LGA), common hepatic (CHA) and splenic artery (Standring et al., 2009). Branching pattern of CT may vary from above mentioned classical three to four, five or six. Additional branches include inferior phrenic artery, dorsal pancreatic artery, middle colic or accessory middle colic artery (Hamilton and Mossman, 1972; Amonoo‐Kuofi et al., 1995). Anastmosis between CT and Superior mesenteric artery (SMA) which supplies the midgut derivatives in the form of Bühler's arcade (1‐2%) is present posterior to the body of pancreas (Douard et al., 2006; McNulty et al., 2001). Anastomoses between SMA and Inferior mesenteric artery (IMA) which supplies hindgut derivatives are also documented (Lange et al, 2007; Van Damme and Bonte, 1990). Until recently no communications between arteries of foregut and hindgut were reported (Manoharan et al., 2010; Patel et al., 2010; Stimec et al., 2011). We report the first cadaveric finding demonstrating a direct communication between the stems of CT and left colic artery (LCA) via a fourth anomalous CT branch in the absence of any co‐existing stenosis or aneurysm in the main vessels. Clin. Anat. 26:984–986, 2013. © 2012 Wiley Periodicals, Inc.  相似文献   
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Despite the growing evidence regarding the effectiveness of cognitive–behavioral interventions in reducing occupational stress, very few studies have examined its effectiveness among nurses. This study investigated the impact of a cognitive–behavioral (CB) course on the nurses' well-being. The study compared the sense of coherence (SOC), perceived stress (PSS), and mood states of 20 nurses who had participated in the CB course to that of 16 control participants using a pre–post test design. At baseline (t1), no significant differences were found between the two groups in SOC, PSS, and mood states. The effects within each group controlling for t1 were examined by analysis of covariance. At t2, a significant increase in SOC and the mood state of vigor and a significant decrease in PSS and fatigue were found only among participants in the CB course. The results are discussed in relation to the conceptual framework of stress and coping theory.  相似文献   
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