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The distribution of nerves immunoreactive to protein gene product 9.5 (PGP 9.5), tyrosine hydroxylase (TH), neuropeptide Y (NPY), substance P (SP) and calcitonin gene related peptide (CGRP) antisera was investigated in the atrioventricular valves of the Sprague–Dawley rat and the Dunkin–Hartley guinea pig using confocal and epifluorescence microscopy. No major differences were noted between the innervation of the mitral and tricuspid valves in either species. For all antisera the staining was more extensive in the guinea pig valves. Two distinct nerve plexuses separated by a ‘nearly nerve free’ zone were identified in both species with each antiserum tested. This was most apparent on the anterior cusp of the mitral valve. The major nerve plexus extends from the atrioventricular ring through the basal, intermediate and distal zones of the valves towards the free edge of the valve cusp. These nerve bundles, arranged as primary, secondary and tertiary components, ramify to the free edge of the valve and extend to the attachment of the chordae. They do not contribute to the innervation of the chordae tendineae. The second, minor chordal plexus, runs from the papillary muscles through the chordae tendineae and passes parallel to the free edge of the cusp. The nerves of this minor plexus are interchordal, branching to terminate mainly in the distal zone, free edge of the valve cusp and adjacent chordae tendineae. Some interchordal nerve fibres loop from a papillary muscle up through a chorda, along the free edge and pass down an adjacent chorda into another papillary muscle. The nerve fibres of the major and minor plexuses intermingle although no evidence was found for interconnectivity between them. In the distal zone between the major plexus which extends from the base of the valve and the minor chordal plexus there is a zone completely free of nerves staining with antisera to TH and NPY. Occasional nerves which stained positive for PGP 9.5, SP and CGRP immunoreactivities crossed this ‘nearly nerve free zone’ passing either from the chordal/free edge nerves to the intermediate and basal zones or vice versa. An additional small nerve plexus which displayed immunoreactivity to CGRP antiserum extended from the atrioventricular ring into the basal zone of the valve cusp. Not all chordae tendineae displayed immunoreactive nerve fibres. It is concluded that the innervation patterns of the sensory and sympathetic neurotransmitters and neuropeptides examined in the atrioventricular valves of the rat and guinea pig are ubiquitous in nature. The complexity of the terminal innervation network of the mammalian atrioventricular valves and chordae tendineae may contribute to the complex functioning of these valves in the cardiac cycle.  相似文献   
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Sural nerve autografts were performed on intact rat sural nerves and on sural nerves excised proximal to the site of grafting. The effect of the presence or absence of regenerating axons upon reconstitution of the perineurium at the graft junctions and upon re-establishment of the blood-nerve barrier to horseradish peroxidase (HRP) were studied over the succeeding 3--24 weeks. Compartmentation of the nerve fascicle occurred at the graft junctions where the perineurium was damaged. Each compartment contained Schwann cells with or without axons and was surrounded by elongated fibroblast-like cells which resembled perineurial cells in the longer surviving animals. It was concluded that, (a) compartments form in a nerve at the site of perineurial damage even in the absence of axons; (b) although compartmentation may be a mechanism for perineurial regeneration and reconstitution of the blood-nerve barrier, blood vessels and the cell layers forming compartments at graft junctions remain permeable to HRP for at least 6 months; and (c) the intact perineurium around the distal stump of a denervated nerve is permeable to HRP but the endoneurial blood vessels are not.  相似文献   
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Objective: To assess the validity, reliability and comprehensibility of the Developed Arabic Multidimensional Health Assessment Questionnaire (Arabic‐MDHAQ) for use in standard clinical care of patients with rheumatic diseases. Methods: The multidimensional questionnaire was developed on a one‐page sheet. One side includes 10 activities of daily living (Arabic HAQII), four items to assess psychological distress, duration of morning stiffness as well as visual analogue scales for pain, global status, and fatigue. The other side includes review of the systems, falls and cardiovascular risk assessment, the rheumatology attitudes index to assess the psychological construct of helplessness and self‐report of joint counts. The questionnaire was completed by consecutive patients with various rheumatic diseases including 85 with rheumatoid arthritis, 57 with fibromyalgia, 57 with osteoarthritis, 18 with psoriatic arthritis and 11 with ulcerative colitis. Results: The test was reliable as demonstrated by a high standardized alpha‐value and minimal changes recorded in the second from the first test. The Developed Arabic‐MDHAQ correlated significantly with clinical parameters of disease activity as well as inflammatory markers. Changes in both functional and psychological assessment scores showed variation with diseases. The Arabic health assessment questionnaire II (functional disability) was significantly correlated with the original Arabic‐HAQ. The psychological assessment items in the Arabic‐MDHAQ were significantly correlated with depression as well as anxiety scores as demonstrated by Hamilton scales for depression and anxiety (P < 0.001). The Arabic‐MDHAQ showed also a high degree of comprehensibility (92.9%). Conclusion: The Developed Arabic‐MDHAQ is a reliable and valid instrument for assessment of Arabic patients suffering from rheumatic diseases. Being short, rapid and comprehensive, this adds more to its applicability. The data support the value of completion of the simple 2‐page patient questionnaire, which provides a quantitative written documented record by the patient, at each visit to a rheumatologist.  相似文献   
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J Wave Syndromes . Introduction: Recently, great attention has been paid to the risk stratification of asymptomatic patients with an electrocardiographic early repolarization (ER) pattern. We investigated several repolarization parameters including the Tpeak‐Tend interval and Tpeak‐Tend/QT ratio in healthy individuals and patients with J wave syndrome who were aborted from sudden cardiac death. Methods and Results: Ninety‐two subjects were enrolled: 12 patients with ventricular fibrillation associated with J waves, 40 healthy subjects with an uneventful ER pattern and 40 healthy control subjects (C) without any evident J waves. Using ambulatory electrocardiogram recordings, the average QT interval, corrected QT interval (QTc), Tpeak‐Tend (Tp‐e) interval, which is the interval from the peak to the end of the T wave, and Tp‐e/QT ratio were calculated. Using ANOVA and post hoc analysis, there was no significant difference in the average QT and QTc in all 3 groups (QT; 396 ± 27 vs 405 ± 27 vs 403 ± 27 m, QTc; 420 ± 26 vs 421 ± 21 vs 403 ± 19 milliseconds in the C, ER pattern and J groups, respectively). The Tp‐e interval and Tp‐e/QT ratio were significantly more increased in the J wave group than the ER Pattern group (Tp‐e: 86.7 ± 14 milliseconds vs 68 ± 13.2 milliseconds, P < 0.001, Tp‐e/QT; 0.209 ± 0.04 vs 0.171 ± 0.03, P < 0.001), but they did not significantly differ between the C and ER pattern groups (Tp‐e: 68.6 ± 7.5 vs 68 ± 13.2, P = 0.97, Tp‐e/QT 0.174 ± 0.02 vs 0.171 ± 0.03, P = 0.4). Conclusion: As novel markers of heterogeneity of ventricular repolarization, Tpeak‐Tend interval and Tp‐Te/QT ratio are significantly increased in patients with J wave syndromes compared to age and sex‐matched uneventful ER. (J Cardiovasc Electrophysiol, Vol. 23 pp. 1109‐1114, October 2012)  相似文献   
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Skeletal maturity in Pakistani children   总被引:1,自引:0,他引:1  
Skeletal maturity in 750 normal Pakistani children (400 males, 350 females) aged 1–18 y was determined by the Greulich–Pyle atlas system. Male children during first year and female children during first 2 y of life matured in conformity with Greulich–Pyle standards. After that period mean bone ages were lower than the American standards up to 15 y in males and 13 y in females (at or around puberty), which may be due to malnutrition, ill health or other environmental factors. After puberty bone ages were higher than the American standards indicating earlier maturity in Pakistani than Western children. Hence for the proper evaluation of skeletal age in a given region, a longitudinal study on individuals in that region to establish normal standards is necessary.  相似文献   
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