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991.
洗胃在我国仍是抢救急性口服毒物中毒的重要措施,口服毒物中毒是生活中误服或有意自服而发生的中毒,是医院急诊科最常见的急症之一,它的发病时间与药物浸入的途经、毒性、剂量等有关。口服毒物中毒,情况紧急严重,若抢救不及时、治疗不当和观察护理不到位,可危及生命,而彻底清除胃肠毒物是抢救口服毒物中毒成功的关键。洗胃用物的合理选择,洗胃液的正确使用以及洗胃方法的不断改进是抢救成功的重要保证。  相似文献   
992.
张育瑆  俞晓军  考晓明  黄云  胡志前 《生物磁学》2011,(11):2049-2052,2070
目的:观察楔形切除胃的不同部位对术后胃电节律的影响。方法:将30只雄性新西兰兔按照完全随机原则分为胃体近端楔形切除组、胃体远端楔形切除组及对照组3个处理组,每组10只。记录在自然恢复状态下术后3日、6日、9日胃体近端及胃窦处30分钟内慢波总数及正常慢波次数并计算正常慢波百分比。用析因设计分析切除部位、测量部位、术后时间三因素对胃慢波节律的影响。结果:上述三因素均对术后慢波节律有影响,切除胃体近端与切除胃体远端相比,前者引发的术后胃电节律紊乱的程度更严重且恢复更缓慢;术后测量胃窦处与测量胃体处相比,前者发生的胃电节律紊乱的程度更严重且恢复更缓慢。结论:大弯侧胃底与胃体交医院界处的“胃电起始区域”即为“胃电起搏区”,“胃电起搏区”的切除时术后胃电节律的影响大于传导区域切除对其影响、  相似文献   
993.
Calcitonin gene-related peptide (CGRP) is a 37 amino acid peptide recently demonstrated to be a peptide expressed by the calcitonin gene in the rat central nervous system. Intracerebroventricular administration of CGRP in pylorus ligated rats resulted in a dose dependent suppression of gastric acid secretion. This effect was also present in acutely vagotomized rats. In addition, CGRP inhibited the stimulation of gastric acid secretion by thyrotropin releasing hormone. CGRP was considerably less potent in its effect on gastric acid than calcitonin, a well known central inhibitor of gastric acid secretion in the rat. This study suggests that CGRP may be a factor in the central regulation of gastric acid secretion in the rat.  相似文献   
994.
Summary The interaction between adult stratified squamous epithelium and its supporting connective tissue possibly involves both permissive and directive influences. To examine the effect of vitality and specificity of connective tissue on the maintenance of epithelial structure and histo-differentiation, specimens of skin and oral mucosa from various regions of adult mice were separated using either EDTA or trypsin. Prior to transplantation, the epithelium was recombined with either inverted homologous connective tissue or with connective tissue that had been killed either by heating or repeated freeze-thawing. Epithelial sheets were also transplanted onto the graft bed alone or in combination with striated muscle or tendon.Normal patterns of cytodifferentiation were maintained when the epithelium was recombined with inverted or frozen-thawed subepithelial connective tissue but there was a loss of spatial organization on the frozen-thawed connective tissue. In contrast, heat-killed or trypsin-treated frozen-thawed subepithelial connective tissue and non-dermal connective tissue failed to maintain a viable epithelium. These observations suggest that subepithelial connective tissues (dermis, lamina propria) but not deep connective tissues facilitate epithelial proliferation and histodifferentiation.Supported by NIH/NIDR RO1 DEO5190  相似文献   
995.
Summary The anterior oesophageal sensilla (AOS) of Astacus astacus are short cuticular cylinders with a terminal pore. Three sensory cells belong to each AOS, two of them having a dendritic ciliary segment of about 2 m length (A-cells), the third having this segment about 12 m long (B-cell). The ciliary A-tubules in the B-cells only possess arms and an electron-dense core. The dendritic inner segments of the A-cells terminate 3–6 m distal of the B-cells. The dendritic tips of most A-cells are connected by desmosomes. All dendritic inner segments contain a ciliary rootlet and are accompanied by a scolopale within the innermost enveloping cell. There are four enveloping cells, three of which form thin subepithelial columns together with the enclosed sensory cells. Recordings from the posterior branch of the anterior oesophageal nerve containing the axons of the AOS revealed the presence of three types of sensory cells, two being chemosensitive and one mechanosensitive. One chemoreceptor is specifically sensitive to nicotinamide, but responded also to -NAD, 6-aminonicotinamide, nicotinamide methyl esther and nicotin. It was blocked by p(4)-acetylpyridine. The second chemoreceptor responded only to crayfish gastric fluid. The mechanoreceptors reacted to stretch of the oesophageal wall adapting only slowly to maintained stimuli. It is assumed that the A-cells are the chemosensitive cells and the B-cells the mechanosensitive ones. The latter show only a small number of modality-specific characteristics. Several structural features appear to be correlated with the location of the AOS within a flexible surface, which undergoes considerable dilation.Supported by the Deutsche Forschungsgemeinschaft (H.A.:SFB 4/G1; H.H.: HA 1201/1-4)  相似文献   
996.
Zusammenfassung In der Regio olfactoria des Goldfisches (Carassius auratus) werden intraepitheliale Drüsen und deren Oberflächenstruktur beschrieben. Die Stadien der Sekretanhäufung, der Sekretausscheidung und der Bedeutung für die Bildung des Schleimfilmes über der olfaktorischen Rosette werden demonstriert und diskutiert. Zwei unterschiedliche Erscheinungsbilder von Drüsen werden beschrieben, bei denen es sich jedoch möglicherweise nur um zwei Modifikationen ein und desselben Zelltyps handelt: 1. Drüsen, die als Becherzellen bezeichnet werden und 2. Drüsen, deren ballonartige Vorwölbungen ihrer distalen Zellpole weit über die Oberfläche des olfaktorischen Epithels hinausragen. Diese beiden Drüsen unterscheiden sich in ihrer Häufigkeit, ihrer Verteilung auf den Lamellen der olfaktorischen Rosette, ihrem Sekretionsmechanismus und ihrer Oberflächenbeschaffenheit, nicht jedoch im lichtmikroskopischen Erscheinungsbild ihrer Sekrettropfen.Auf der Oberfläche der Becherzellen lassen sich zwei verschiedene Typen von Mikrovilli mit jeweils unterschiedlichem Verteilungsmuster erkennen: 1) ca. 0,15–0,5 lange Mikrovilli die in wechselnder Dichte über die gesamte Oberfläche der Drüsenzellen verteilt sein können und 2) bis ca. 1 lange Mikrovilli, die wie ein Stäbchensaum den Verlauf benachbarter Zellmembranen markieren. Außer diesen beiden Oberflächenprofilen kommen noch Strukturen vor, die in Ein- oder Mehrzahl auf der Oberfläche der Becherzellen erscheinen können und als Bündel verwachsener Zilien interpretiert werden. Sie sind bis zu 5 lang, ihr Basisdurchmesser beträgt ca. 1 und sie verjüngen sich im allgemeinen zur Spitze hin.Die Existenz von microspines an den Zilien der den Becherzellen stets benachbarten Flimmerzellen wird beschrieben.Die Existenz eines terminalen Filmes auch über dem olfaktorischen Saum von Teleostiern konnte erstmalig nachgewiesen werden.
Scanning electron microscopy of the olfactory glands in the gold fish (Carassius auratus)
Summary The appearance and fine structure of the surface of endoepithelial glands in the regio olfactoria of Carassius auratus are described. The phases of accumulation of secretory droplets, their excretion, and their significance for the production of the terminal mucous film are demonstrated and discussed.Two different kinds of endoepithelial glands formation are described. It is possible that these glands are only modifications of a single cell type. The first modification is referred to as goblet cells; the second as endoepithelial glands with balloon-like projections over the surface of the olfactory epithelium.On the surface of the goblet cells, two classes of microvilli, which differ in structure and pattern of distribution, can be seen. In addition, membrane protrusions, which are interpreted as bundles of fused cilia, can sometimes be found.The goblet cells always appear with ciliated cells in well defined areas. The cilia of ciliated cells are characterized by the existence of microspines.The terminal mucous film, which until now was described only in land-living vertebrates is demonstrated in fish for the first time.
Die Verfasser danken Frau Dr. M. Pfautsch, Herrn Professor Dr. G. Pfefferkorn und Herrn J. R. Pfefferkorn (alle Institut für Medizinische Physik der Universität Münster) für wertvolle Kritik und uneingeschränkte Hilfsbereitschaft bei der Durchführung der ersten rastermikroskopischen Gewebsaufbereitung; Herrn Karl Donberg und Herrn Karl Wolzenburg danken sie für sorgfältige technische Assistenz.  相似文献   
997.
Summary In an attempt to further our knowledge about the structure and function of the recently identified intrapulmonary Neuro-epithelial Bodies (NEB's) (Lauweryns et al., 1972a, 1972b), lungs of 84 neonatal rabbits and 6 neonatal mice were studied along four different lines of investigation. Several routine and silver staining methods, Falck's fluorescent amine technic and histochemical and electron microscopical techniques were performed.1. In order to test the probable chemoreceptor function of the NEB's, animals were exposed to hypoxia. Under such circumstances, the corpuscular cells of the NEB's secrete their dense-cored, serotonin-containing vesicles at their basal vascular pole. 2. After reserpine pretreatment, the NEB's of otherwise normal animals reveal a distinct amine depletion, the corpuscular cells exhibiting a decreased yellow fluorescence and ultrastructurally a clearing up of their dense-cored vesicles. 3. Studied on serial sections with the electron microscope, various types of morphologically afferent-like and efferent-like nerve endings, making contact as well with the corpuscular cells as amongst themselves have been detailed. 4. Cytochemically the corpuscular cells react positively with alpha-glycerophosphate dehydrogenase, acetylcholinesterase and Solcia's lead hematoxylin stain for endocrine cells producing polypeptides and amines.It is proposed that the NEB's provide an intrapulmonary, hypoxia-sensitive neuro(chemo-) receptor system in addition to the well established central and peripheral (e.g. carotid body) chemoreceptors. They contain and secrete serotonin and probably also related amines or peptides, which could influence the pulmonary vasoconstrictor response. According to classic morphologic criteria, they possess a dual innervation, both afferent and efferent.Various other possible functions of the NEB's in normal and diseased lungs are briefly proposed.This study has been supported by a grant from The Council for Tobacco Research — U.S.A. and the Nationaal Fonds voor Wetenschappelijk Onderzoek — Belgium. We thank P. Theunynck for performing some of the histochemical studies, B. Van Rijkel, B. Emanuel and R. Renwart for technical, G. Pison and St. Ons for photographical and N. Tyberghien for secretarial assistance.  相似文献   
998.
目的通过观察大豆低聚糖对胃癌癌细胞株BGC-823细胞的细胞周期和细胞凋亡的影响,探索乳酸杆菌发酵滤液对胃癌细胞作用的可能机制。方法用光镜和流式细胞仪分析不同浓度大豆低聚糖对BGC-823细胞的凋亡诱导效果;用流式细胞仪分析不同浓度大豆低聚糖对BGC-823细胞细胞周期的影响。结果大豆低聚糖可以诱导BGC-823细胞的凋亡。形态学观察处理后的BGC-823细胞,可见细胞变形,细胞皱缩,体积变小,细胞间隙增大,细胞核固缩。流式细胞仪分析50 mg/ml和100 mg/ml大豆低聚糖作用48 h和72 h BGC-823细胞的凋亡比例,分别为6.76%和7.93%。50 mg/ml大豆低聚糖作用48 h,引起BGC-823细胞G1期阻滞,100 mg/ml大豆低聚糖作用48 h,引起BGC-823细胞出现S期阻滞。结论大豆低聚糖可诱导部分BGC-823细胞凋亡。大豆低聚糖对BGC-823细胞的生长抑制作用在低浓度时可能通过G1期阻滞实现,在高浓度时可能通过S期阻滞实现。  相似文献   
999.
目的:研究胃动素对下丘脑弓状核胃牵张敏感神经元放电活动和胃运动的影响。方法:采用4管玻璃微电极细胞外记录胃动素对大鼠弓状核胃牵张敏感神经元活动,采用胃内置传感器观察胃动素对对清醒大鼠胃运动的影响。结果:65.5%的弓状核神经元为胃扩张敏感性神经元,其中55.6%为胃扩张兴奋性神经元,44.4%为抑制性神经元。胃扩张刺激后兴奋性神经元的放电频率显著增加(P<0.01),而抑制性神经元的放电频率显著降低(P<0.01)。弓状核内微量注射胃动素,70%的兴奋性神经元在胃扩张刺激后表现为兴奋作用,17.5%的神经元表现为抑制作用,并且放电频率显著增加(P<0.05)。同样,在抑制性神经元中,65.6%在注射胃动素后引起电活动增强,放电频率显著降低(P<0.05)。而胃动素受体拮抗剂GM-109可以完全阻断这种由胃动素诱导的兴奋作用,提示,胃动素在弓状核通过其特异性受体调控神经元活动。在胃运动实验中,弓状核微量注射胃动素后,胃运动的收缩频率和幅度都显著增加(P<0.05);同时,这种兴奋作用也可被GM-109阻断。结论:研究证实了弓状核胃动素神经元接收来自胃感受器的外周躯体感觉传入神经的冲动,并通过某些下级核团通路发挥...  相似文献   
1000.
The identification of proteins aberrantly expressed in malignant B-cells can potentially be used to develop new diagnostic, prognostic or therapeutic targets. Proteomic studies of B-cell malignancies have made significant progress, but further studies are needed to increase our coverage of the B-cell malignant proteome. To achieve this goal we stress the advantages of using sub-cellular fractionation, protein separation, quantitation and affinity purification techniques to identify hitherto unidentified signalling and regulatory proteins. For example, proteomic analysis of B-cell plasma membranes isolated from patients with mantle cell lymphoma (MCL) identified the voltage-gated proton channel (HVCN1,[1]). This protein has now been characterised as a key modulator of B-cell receptor (BCR) signalling and abrogation of HVCN1 function could have a role in the treatment of B-cell malignancies dependent on maintained BCR signalling [2]. Similarly, proteomic studies on cell lysates from prognostic subtypes of CLL, distinguished by the absence (UM-CLL) or presence (M-CLL) of somatic hypermutation of the immunoglobulin heavy chain locus identified nucleophosmin 1 (NMP1) as a potential prognostic marker [3,4]. Thus, targeted proteomic analysis on selected organelles or sub-cellular compartments can identify novel proteins with unexpected localisation or function in malignant B-cells that could be developed for clinical purposes.  相似文献   
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