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101.
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Recent advances in the study of cardiac development have shown the relevance of addition of myocardium to the primary myocardial heart tube. In wild‐type mouse embryos (E9.5–15.5), we have studied the myocardium at the venous pole of the heart using immunohistochemistry and 3D reconstructions of expression patterns of MLC‐2a, Nkx2.5, and podoplanin, a novel coelomic and myocardial marker. Podoplanin‐positive coelomic epithelium was continuous with adjacent podoplanin‐ and MLC‐2a‐positive myocardium that formed a conspicuous band along the left cardinal vein extending through the base of the atrial septum to the posterior myocardium of the atrioventricular canal, the atrioventricular nodal region, and the His‐Purkinje system. Later on, podoplanin expression was also found in the myocardium surrounding the pulmonary vein. On the right side, podoplanin‐positive cells were seen along the right cardinal vein, which during development persisted in the sinoatrial node and part of the venous valves. In the MLC‐2a‐ and podoplanin‐positive myocardium, Nkx2.5 expression was absent in the sinoatrial node and the wall of the cardinal veins. There was a mosaic positivity in the wall of the common pulmonary vein and the atrioventricular conduction system as opposed to the overall Nkx2.5 expression seen in the chamber myocardium. We conclude that we have found podoplanin as a marker that links a novel Nkx2.5‐negative sinus venosus myocardial area, which we refer to as the posterior heart field, with the cardiac conduction system. Anat Rec, 290:115–122, 2007. © 2006 Wiley‐Liss, Inc.  相似文献   
103.
We investigated effects of sleep on pain-related somatosensory evoked potentials (SEP) following painful electrical stimulation of the left index finger. The biggest advantage of this method is that signals ascending through both A-beta fibers relating to touch and A-delta fibers relating to pain can be recorded simultaneously. While the subject was awake, non-painful stimulation evoked early- and middle latency components, N20, P30 and N60, at the C4 electrode, and painful stimulation evoked not only early- and middle latency components at the C4 but also later pain-specific components, N130 and P240, at the Cz electrode. During sleep, N20 and P30 did not show a significant change in amplitude, N60 showed a slight but significant amplitude reduction, and N130 and P240 significantly decreased in amplitude or disappeared, as compared with those while awake. Therefore, we speculate on the mechanisms generating each component as follows; (1) N20 and P30 are the primary components generated in SI ascending through A-beta fibers. (2) N60 is the secondary component generated in SI involving cognitive function to some degree. (3) N130-P240 are the pain-specific components ascending through A-delta fibers, and closely related to cognitive function, because they were much affected by consciousness, different from the components ascending through A-beta fibers.  相似文献   
104.
A few studies have examined neuropsychological functions, sleep, and mental health combined in Klinefelter syndrome (KS; 47,XXY). We investigated neuropsychological functions with standard tests, sleep with actigraphy, and self‐reported mental health in 30 men with KS (Mean age = 36.7 years) compared to 21 controls (Mean age = 36.8 years). Men with KS scored significantly lower on mental speed, attention span, working memory, inhibition, and set‐shifting tests, as well as overall IQ (mean effect size difference Cohen's d = 0.79). Men with KS had significantly longer night wakes, with no differences in other sleep variables (mean d = 0.34). Men with KS reported poorer mental health than controls (mean d = 1.16). Regression analyses showed neuropsychological functions explained variance in some sleep domains for men with KS but not for controls. Neuropsychological functions explained variance in some mental health domains for controls. For men with KS, however, verbal IQ was the only significant predictor of mental health. Altogether, men with KS display problems in neuropsychological functions and mental health but do not appear different from controls on most sleep parameters. Our findings indicate that relations between neuropsychological functions, sleep, and mental health differ between men with KS and controls.  相似文献   
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We have isolated the complete coding region of HLA‐B*39 from a Spanish Caucasoid, using a new PCR primer for its 5′ untranslated region. The cDNA matched partial genomic sequences of B*3924, an allele whose distribution appears to be restricted to Mediterranean and Arabian Caucasoids. A single amino acid change exclusive to B*3924 (threonine‐98) distinguishes it from B*3903.  相似文献   
108.
Coagulopathy associated with massive transfusion (MT) remains an important clinical problem. The author attempted to identify the causes of coagulopathy in massively transfused, adult and previously haemostatically competent patients and to differentiate between the elective surgical and the emergency settings. A MEDLINE search was conducted for articles published on ‘massive transfusion’, ‘transfusion’, ‘trauma’, ‘surgery’, ‘coagulopathy’ and ‘haemostatic defects’. A narrative format was adopted. Coagulopathy associated with MT is an intricate, multifactorial and multicellular event. In patients undergoing elective surgery, a decrease in fibrinogen concentration is observed initially while thrombocytopenia is a late occurrence. Critically low levels of coagulation factors were seldom reported when whole blood was in common use. With the use of packed red blood cells (PRBC), dilution or consumption of coagulation factors has become a significant issue requiring specific treatment with, primarily, fresh frozen plasma (FFP). In the emergency setting (e.g., trauma, ruptured abdominal aortic aneurysm), tissue trauma, shock, tissue anoxia and hypothermia contribute to the development of disseminated intravascular coagulation and microvascular bleeding. It has been shown that the proactive administration of platelets and FFP improves coagulation, decreases haemorrhage and improves survival in these massively bleeding patients. We can only speculate that in this specific context, the benefits of early and aggressive platelet and coagulation factor replacement are related to the ongoing consumption coagulopathy at the time of surgery.  相似文献   
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The frequency and distribution of deletions of 19 deletion-prone exons clustered in two hot spots in the proximal and central regions of the dystrophin gene were compared in three populations from Singaporean, Japan, and Vietnam. DNA samples obtained from 105 Singaporean, 86 Japanese, and 34 Vietnamese Duchenne muscular dystrophy patients were examined by polymerase chain reaction amplification. Deletions of the examined exons were found in 51.2% of Japanese patients but in 40.0% or less of the Singaporeans and Vietnamese. About two thirds of the deletions were localized in the central region and the remaining deletions were clustered at the proximal region. The most commonly deleted exons at the central deletion hot spot were exon 50 in the Singaporean, exons 49 and 50 in the Japanese, and exon 51 in the Vietnamese population. At the proximal deletion hot spot, the most commonly deleted exons were exons 6 and 8 in the Singaporeans, exons 12 and 17 in the Japanese, and exons 8 and 12 in the Vietnamese. Two cases each from Singapore and Japan had large-scale gross mutations spanning both deletion hot spots. Our results suggest that, although the presence and frequency of the two deletion hot spots may be similar in the three Asian populations analyzed, the distribution and frequency of deletions among the different exons can vary as a result of population-specific intronic sequences that predispose individuals to preferential deletion breakpoints. Received: May 20, 2002 / Accepted: July 1, 2002  相似文献   
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