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51.
52.
Summary Just as cAMP is regarded as an intracellular mediator of histamine, so has cGMP been connected with cholinergic stimulation of gastric acid secretion. The object of the present investigation was to study the possible role of cellular cGMP on 14C-aminopyrine uptake, an indirect measure of parietal cell H+-production, by using mixtures of isolated rat gastric cells and fractions with different parietal cell content.
Cellular cAMP and cGMP. The phosphodiesterase inhibitor 3-isobutyl-1-methylxanthine (IBMX) enhanced the cAMP and cGMP of gastric cells in a time- and concentration-dependent manner, by 98 and 124% (1 mmol/l) and was included in all further studies. In parietal cell enriched fractions, histamine elevated cAMP by 109% (100 mol/l) without changing cGMP while carbachol did not influence either nucleotide. Various thiols and nitrogen compounds strongly enhanced cellular cGMP, e. g. hydroxylamine and l-cysteine (1 mmol/l) by 527 and 656%, whereas changes in cAMP were minimal. The hydroxylamine response occurred in parietal cell depleted and enriched fractions.
14
C-aminopyrine (AP) uptake. IBMX alone reduced the basal AP uptake, potentiated the effect of histamine and inhibited the effect of carbachol, which alone stimulated basal accumulation by 302%. The most efficacious stimulant of parietal cell H+-production was dibutyryl cAMP (582%, 100 mol/l), whereas dibutyryl cGMP was without effect. However, this latter compound (1 mmol/l) reduced AP accumulation due to dibutyryl cAMP almost completely. Thiols and nitrogen compounds all more or less reduced AP uptake.The data contraindicate the theory of a second messenger function for cGMP in cholinergic acid stimulation of the rat stomach. They show, that an increase in cGMP is associated with low H+-production, even if cAMP levels are raised above their resting state. Thus, the results suggest that cGMP rather mediates inhibition of acid secretion, possibly by counteracting the messenger function of cAMP.This study was supported by the Deutsche Forschungsgemeinschaft 相似文献
53.
Zusammenfassung Ein cellularer Automat, der eine vereinfachte Abschätzung von Verteilungsmustern der Magendurchblutung erlaubt, wird beschrieben. Die auf der Basis des Energiebedarfs der Säuresekretion und der Morphologie der Magenstrombahn simulierbaren Umverteilungsphänomene stimmen in Form und Lage mit dem menschlichen Magengeschwür überein. Sonderfälle der peptischen' Läsion, wie das lineare Geschwür oder die peptische' Stenose der Speiseröhre, sind mit der Theorie des submucösen Steal-Phänomens zu vereinbaren.
Gastric ulcer as a problem of energy balance: Design of a cellular automaton for simulation of disorders of blood flow distribution to the stomach wall
Summary A cellular automaton is described, which allows a simple simulation of patterns of gastric blood flow distribution. Effects of redistribution, which can be simulated on the basis of the energy requirements of acid secretion and the morphology of the gastric vascular bed, are isomorph to form and site of gastric ulcer in man. Special forms of the peptic lesion as linear ulcers or peptic stenoses of the oesophagus are consistent with the theory of a submucous steal-phenomenon.
Herrn Prof. Dr. Dr. rer. nat. h. c. Friedrich Stelzner zum 65. Geburtstag gewidmet 相似文献
54.
我国正常生育力男子精浆的微量元素研究 总被引:12,自引:5,他引:7
本文报告测试了68例正常生育力成年男子精浆中的锌、铜,铁等微量元素和镁,测试结果如下:锌130±5.64μg/ml,铜1.84±0.158μg/ml,铁0.801±0.104μg/ml,镁103.86±10.01μg/ml。所测得的数值均在正常范围内。在正常范围内的精液,精浆中的锌、镁含量与精液质量(精子密度和活动力)之间无显著差异。但铜的含量与精子活动度关系密切,含量高则活动度差,反之则活动度好。铁的含量与精子密度关系也十分密切,含量高时精子密度也高。 相似文献
55.
W. Rau W. Eichelkraut A. Rasche 《Langenbeck's archives of surgery / Deutsche Gesellschaft fur Chirurgie》1986,367(2):139-145
Zusammenfassung Der Einfluß von Pentagastrin auf die Durchblutung des Hundemagens wurde mit 9-Mikrosphären untersucht. Schon 6 min nach dem Beginn der Pentagastrin-Infusion nimmt bei nüchternen Tieren der Fluß in allen Magenarealen zu. Mißt man die Änderung der Durchblutung zwei Stunden postprandial, so findet sich ein Durchblutungsanstieg lediglich im Bereich der Corpusmucosa, während die Antrummucosadurchblutung unter den Ausgangswert abfällt. Dieses intragastrale Steal-Phänomen findet auf der Ebene des submucösen Plexus statt.
Experimental conditions for the reproduction of a submucous steal-phenomenon in the dog stomach
Summary The influence of pentagastrin on gastric blood flow has been investigated using 9-microspheres in dogs. As soon as 6 min after the onset of a pentagastrin infusion blood flow rises in all gastric probes in fasted animals. In dogs, fed two hours previously, such a response can only be seen in the corpus-mucosa areas. Blood flow in the antrum mucosa specimen falls beneath its initial value. This gastric steal-phenomenon takes place at the level of the submucous plexus, as has been shown earlier.相似文献
56.
57.
Bunshiro Akikusa Yasushi Harihara Yoshinobu Nagato Masakazu Nobori 《Pathology international》1992,42(4):293-297
A case of low grade fever developing about a month before the discovery of gastric carcinoma is reported. No findings of infection or collagen disease were revealed. The fever continued for about 3 months, but promptly disappeared after surgical removal of the tumor. A superficial spreading mucosal carcinoma with minimal invasion to the sub-mucosa was seen in the antrum, showing the features of poorly differentiated adenocarcinoma. In addition, unique venous inflammation was recognized beneath and around the neoplasm. Arteries and lymph vessels did not exhibit any inflammatory changes. It was presumed that the gastric carcinoma had induced phlebitis, which subsequently brought about the fever. As to the pathogenetic mechanism, it was suggested that a substance produced by the carcinoma cells flowed into nearby veins to induce the phlebitis. Acta Pathol Jpn 42 : 293-297, 1992. 相似文献
58.
Pattinson H.Anthony; Mortimer David; Curtis Elizabeth F.; Leader Arthur; Taylor Patrick J. 《Human reproduction (Oxford, England)》1990,5(2):167-173
The treatment of antibody-mediated spermagglutination by corticosteroidtherapy has a high incidence of side-effects and sperm washingis often followed by re-agglutination. The possibility of enzymaticdisagglutination was therefore investigated. In the first partof the study the effects of four proteases on sperm motility,vitality and longevity were evaluated. Subtilisin had prohibitivelydetrimental effects even at 10 U/ml. However, chymotrypsin (500U/ml), trypsin (500 U/ml) and papain (50 U/ml) had no adverseeffects. In the second series of experiments one or more ofthese latter three enzymes was found to disagglutinate spermatozoawhich had previously been incubated with sperm-agglutinatingantibody-positive sera in 87% of cases. Although further investigationis required, enzymatic disagglutination may be beneficial forthe treatment of immunologically mediated spermagglutination. 相似文献
59.
60.
黄参方剂诱导胃癌癌前病变细胞凋亡和影响BCL—2蛋白表达的研究 总被引:2,自引:0,他引:2
目的:探讨黄参方剂对胃癌癌前病变细胞凋亡及相关基因表达的影响。方法:将72例胃癌癌前变患者随机分为2组,治疗组37例,口服黄参方剂60ml/d;对照组35例,口服维酶素片12片/天,疗程2月。治疗后胃镜同一部位取材,检测治疗前后细胞凋亡指数和BCL-2蛋白的表达。采用原位末端标记法(TUNEL)检测细胞凋亡,采用免疫组化检测BCL-2蛋白的表达。结果:黄参方剂组服药前后细胞凋亡指数分别为(19.8 相似文献