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51.
Variations of the origin of the artery of the sinoatrial node in normal human hearts 总被引:8,自引:0,他引:8
Summary The artery of the sino-atrial node was studied in 100 normal human hearts after injection of each coronary artery with coloured gelatine containing a radiopaque substance. The hearts belonged to 69 males and 31 females, being 64 Caucasians and 36 non-Caucasians (Negroes and Mulattoes) whose age ranged from 7 to 80 years. Since the individuals had committed suicide or were victims of accidents, their hearts, after pathologists' evaluation, were considered normal. The sinoatrial node of the normal human heart is supplied by the right coronary artery more frequently (58%±4.9% of the cases) than by the left (42%±4.9). The right anterior medial atrial artery, originating from the right coronary at the level of the medial third of the right anterior quadrant of the atrial dome, is most frequently (50%±5) responsible for the blood supply of the sinoatrial node. Among the branches of the left coronary artery, the left anterior medial atrial artery, originating at the level of the medial third of the left. anterior quadrant of the atrial cupola, was the most frequent blood supplier (25%±4.3) of the sinoatrial node. The origin of the artery of the sinoatrial node from the proximal portion or trunk of the left coronary artery was less frequent (12%±3.2) than the origin from the circumflex artery (30%±4.5). Neither sex nor race influenced the variations of the origin of the sino-atrial node.
Variations d'origine de l'artère du noeud sinu-atrial du coeur humain normal
Résumé L'a. du noeud sinu-atrial a été étudiée sur 100 coeurs humains normaux après injection de chaque a. coronaire à la gélatine colorée additionnée d'une substance radio-opaque. Les coeurs provenaient de 69 hommes et 31 femmes, 64 caucasiens et 36 non caucasiens (nègres et mulâtres) âgés de 7 à 80 ans. Ces sujets étant décédés par suicide ou des suites d'accidents, leurs coeurs ont été considérés comme normaux après examen anatomo-pathologique. Le noeud sinu-atrial du coeur humain est vascularisé par l'a. coronaire droite plus fréquemment (58 %±4,9) que par l'a. coronaire gauche (42 %±4). L'a. atriale antéro-médiale droite, issue de l'a. coronaire droite au niveau du tiers médial du quadrant antérieur droit du dôme atrial est l'artère la plus fréquemment en cause (50 %±5) dans la vascularisation du noeud sinuatrial. Parmi les branches de l'a. coronaire gauche, l'a. atriale antéro-médiale gauche, née au niveau du tiers médial du quadrant antérieur gauche du dôme atrial, était la branche la plus fréquemment en cause (25 %±4,3) dans la vascularisation du noeud sinu-atrial. La naissance de l'a. du noeud sinu-atrial à partir de la partie proximale ou du tronc de l'a. coronaire gauche était moins fréquente (12 %±3,2) que son origine à partir du rameau circonflexe (30 %±4,5). Les variations d'origine de l'a. du noeud sinu-atrial n'apparaissaient pas influencées par le sexe ou la race.相似文献
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Bidwell J Keen L Gallagher G Kimberly R Huizinga T McDermott MF Oksenberg J McNicholl J Pociot F Hardt C D'Alfonso S 《Genes and immunity》1999,1(1):3-19
The pathologies of many infectious, autoimmune and malignant diseases are influenced by the profiles of cytokine production in pro-inflammatory (TH1) and anti-inflammatory (TH2) T cells. Interindividual differences in cytokine profiles appear to be due, at least in part, to allelic polymorphism within regulatory regions of cytokine gene. Many studies have examined the relationship between cytokine gene polymorphism, cytokine gene expression in vitro, and the susceptibility to and clinical severity of diseases. A review of the findings of these studies is presented. An on-line version featuring appropriate updates is accessible from the World Wide Web site, http://www.pam.bris.ac.uk/services/GAI/cytokine4.htm. 相似文献
55.
Projection neurons in the rat dorsolateral septal nucleus (DLSN) were labeled intracellularly with horseradish peroxidase (HRP) in an in vitro slice preparation. The labeled neurons exhibited widespread 'isodendritic' type dendritic fields. Each of the neurons was identified as a projection neuron by the tracing of its main axon out of DLSN. The axons of these neurons gave rise to intrinsic collaterals which branched to form an extensive axon plexus which was confined to DLSN. These axon collaterals exhibited numerous en passant swellings suggestive of boutons. It is proposed that the recurrent axon collaterals of DLSN projection neurons may form an anatomical substrate for local inhibition within DLSN. 相似文献
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Isolation of immunogenic neuraminidases of human influenza viruses by a combination of genetic and biochemical procedures. 总被引:3,自引:0,他引:3 下载免费PDF全文
M Gallagher D J Bucher R Dourmashkin J F Davis G Rosenn E D Kilbourne 《Journal of clinical microbiology》1984,20(1):89-93
Neuraminidases were purified from reassortant viruses (H6N1 and H6N2) containing the two antigenic subtypes (N1 and N2) found in human influenza viruses. Surface glycoproteins were solubilized with octylglucoside, and the neuraminidase was isolated by chromatography on DEAE-Sephadex. Neuraminidase isolated by this technique coeluted with viral lipids and spontaneously formed liposomes on dialysis. The purified neuraminidase was immunogenic in rabbits, producing a significant antibody response at dose levels as low as 1 microgram. 相似文献
59.
Rats with a neurotoxic lesion of the amygdala central nucleus (CN) in one hemisphere and a 192 immunoglobulin G (192IgG)-saporin lesion of cholinergic neurons in the contralateral substantia innominata/nucleus basalis (SI/nBM) failed to show the enhanced attentional processing of a conditioned stimulus (CS) observed in sham-operated rats when that CS's predictive value was altered. Performance of these asymmetrically lesioned rats was poorer than that of rats with a unilateral lesion of either structure or with a symmetrical lesion of both structures in the same hemisphere. These results implicate connections between the CN and SI/nBM in the incremental attentional processing of CSs, extending previous research that has shown similar effects of bilateral lesions of either the CN or the SI/nBM. 相似文献
60.