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991.
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   
992.
The effects of two kinds of induction speed of sevoflurane anesthesia on the EEG pattern were compared in the same individual using medical student volunteers: a first exposure of 4% was given, followed after full recovery, by incremental doses of 1, 2 and 4% successively, each being administered for 10min. The arterial blood level of the anesthetic was measured using gaschromatograph. The changes of EEG pattern during fast induction with 4% were not represented by the abbreviation of those observed during the slow induction with the incremental doses. The administration of 4% induced a sudden appearance of high voltage, rhythmic slow waves of 2–3Hz at 1–3min when the arterial blood anesthetic level increased maximally, which was then followed by a pattern of faster activities of 10–14Hz mixed with 5–8Hz slow waves. In contrast, the administration of incremental doses induced an increase in frequency and amplitude of EEG activities in the light plane, followed by their decreases in deeper planes. The final EEG patterns were identical for both these methods of induction. These findings confirmed our previous hypothesis that not only the arterial blood level of anesthetics but the rate of its increase are important factors determining the EEG pattern of anesthesia.(Avramov MN et al.: Effects of different speeds of induction with sevoflurane on the EEG in man. J Anesth 1: 1–7, 1987)  相似文献   
993.
In 12 healthy volunteers with at least an experience of six months in autogenic training (AT), the cerebral blood flow (CBF) was measured at rest, in AT and in hypnosis (H). The results were correlated with individual test profiles. The cortical flow pattern at rest of our AT trained volunteers did not show the hyperfrontality which is described in the literature. This may be interpreted as an effect of better and habitualized relaxation in long trained AT practitioners. This flow pattern corresponds to the low grades of neuroticism and aggressivity found in the tests. Furthermore an activation in central cortical areas and a deactivation in regions which are associated with acoustic and autonomous functions occur.Possible explanations for these phenomena as well as for the relatively low perfusion of the left hemisphere at rest and activation in AT are discussed. The global rise of CBF in H may be an activation effect caused by resistance against the hypnotizer: the deeper the trance, the smaller the CBF increase in the motor cortical area needed for maintaining catalepsy of the right arm and in temporal cortical fields processing acoustic inputs.  相似文献   
994.
Blood and semen samples obtained from 24 "normal" volunteers were analyzed for 16 different biochemical parameters. These included: Ca, Mg, K, Na, Zn, Cl, P, glycerolphosphorylcholine (GPC), carnitine, fructose, uric acid, prostatic acid phosphatase, alkaline phosphatase, glutamic oxaloacetic transaminase (SGOT), lactic dehydrogenase (LDH), and glutamic pyruvate transaminase (SGPT). With the exception of uric acid, all the biochemical constituents in seminal plasma were either significantly higher (p less than 0.001, except alkaline phosphatase which was significant at p less than 0.05) or significantly lower (p less than 0.001) than in blood serum. Further, potassium (r = 0.51); carnitine (r = 0.54); and SGOT (r = 0.70) showed a significant direct relationship in blood and seminal plasma.  相似文献   
995.
丹参和黄芪治疗气虚血瘀型心力衰竭的作用   总被引:2,自引:0,他引:2  
本文报道91例气虚血瘀型心力衰竭(心衰)病人选用丹参和黄芪治疗作用。16例作气囊漂浮导管监测,发现黄芪明显增加心排出量、每搏量及心脏指数,而丹参无此作用,提示黄芪有正性肌力作用;30例给黄芪加党参,治疗后心功能分级及某些异常的血液流变学指标均有改善;44例先丹参,继之丹参加黄芪,治疗后心功能分级有明显改善,且能改善异常的血液流变学指标,明显抑制血小板聚集功能。提示丹参具有活血化瘀改善血液流变学及抑制血小板的聚集性,黄芪有补气强心改善心功能的作用。  相似文献   
996.
Summary The role of Ca channel and extracellular Ca2+ on autoregulation of renal blood flow was investigated in the perfused kidney of the anesthetized dog. The perfusion pressure was changed in the range between 60 and 200 mm Hg. Intra-arterial infusion of nifedipine (5 g/min) increased renal blood flow at a perfusion pressure above 100 mm Hg and inhibited autoregulation. Simultaneous infusion of 5 g/min of BAY K 8644 antagonized the effect of nifedipine. Renal blood flow was increased and autoregulatory relationship between flow and perfusion pressure was inhibited by EDTA (30 mg/min) infusion. The inhibitory effect of EDTA on renal autoregulation was counteracted by simultaneous infusion of CaCl2 at 30 mg/min, but not counteracted by that of BAY K 8644 (5 g/min). BAY K 8644 also could not antagonize the inhibitory effect of a vasodilator, papaverine (5 mg/min) on renal blood flow autoregulation. These results provide the evidence that the renal autoregulation involves the process of Ca2+ influx into the vascular smooth muscle cell through the Ca channels. Send offprint requests to N. Ogawa at the above address  相似文献   
997.
Summary In order to determine whether or not glucagon released from the pancreas might have local vascular effects, the actions upon regional haemodynamics in the anaesthetised rat of two doses of glucagon (2 and 10 g kg–1 min–1) infused intrasplenically (and thus into the portal vein) were compared with those of a single dose (2 g kg–1 min–1) infused i. v. Infusion of glucagon i. v. produced a significantly increased heart rate (by 6%) and cardiac output (by 23%) in the experimental animals compared to those receiving saline by the same route. Total peripheral resistance fell by 24%. A greater proportion of the cardiac output passed to the coronary and renal vascular beds and blood flow was increased in the spleen, testes, pectoral skeletal muscle, stomach and small intestine as well as the heart and kidneys.The lower dose infused intrasplenically had no significant effect on cardiac output or total peripheral resistance but significantly increased the proportion of cardiac output passing both to the stomach and the small intestine such that the percentage of cardiac output flowing through the portal vein increased from 19.1 ± 1.1% to 23.8 ± 1.7%.Intrasplenic infusion of 10 g kg–1 min–1 significantly increased cardiac output (by 29%) but reduced total peripheral resistance by 37%. Greater fractions of the cardiac output were received by the spleen, small intestine and epididymides. Blood flow was increased in these organs and the skin, kidneys, stomach, large intestine and the mesentery.It is concluded that pharmacologically effective amounts of glucagon only passed into the systemic circulation with the higher dose infused intrasplenically. Thus the redistribution of cardiac output in favour of the splanchnic bed with the lower dose of glucagon infused into the portal region is most likely the result of local mechanisms rather than a direct effect of the hormone on the inflow vasculature resulting from recirculation. Send offprint requests to C. R. Hiley at the above address  相似文献   
998.
Summary The antihypertensive effects of the hydralazine-related compound cadralazine (2-{3-[6-(2-hydroxypropyl)ethylamino]pyridazinyl}ethyl carbazate, ISF 2469), were investigated in 16 patients with primary hypertension concurrently treated with -blockers and diuretics. The protocol included a double-blind placebo controlled haemodynamic evaluation after the first tablet and two 4-week double-blind placebo controlled cross-over periods followed by an open evaluation during 2 months. Cadralazine induced a moderate, prolonged fall in blood pressure that was associated with vasodilatation and slight increases in cardiac output (dye-dilution) and heart rate. Renal plasma flow (PAH) and glomerular filtration rate (51Cr-EDTA) were not significantly influenced, but the filtration fraction was reduced. Plasma concentrations of noradrenaline and adrenaline rose, whereas plasma renin activity was unchanged. The haemodynamic parameters were not correlated with the plasma concentrations of cadralazine. During chronic cadralazine treatment the supine blood pressure was significantly lower than during the double-blind placebo phase (160/93 vs 174/102 mmHg). The compound was generally well tolerated but the body weight increased slightly (1.1 kg), probably because of fluid retention. Several patients who had previously experienced side effects with hydralazine, including one with hydralazine-syndrome, tolerated cadralazine well. This suggests that cadralazine does not cross-react with hydralazine.  相似文献   
999.
Radiographic quantification of alveolar bone level changes   总被引:3,自引:0,他引:3  
The "random burst" theory has recently been proposed as an explanation of the pattern of periodontal disease progression. The theory predicts that the progression of bone loss at individual sites is not dependent upon previous bone loss and age. A longitudinal radiographic study was designed to test this hypothesis, and to describe the changes in bone level over 2 years in a group of 180 subjects (18-68 years of age) who were not under systematic periodontal treatment. The results indicated that 94% of the sites did not show significant changes in the alveolar bone level during the observation period. The mean annual bone loss for the total population was 0.11 mm. By regressing longitudinal bone loss upon age, it was shown that the rate of bone loss increased rapidly between 33 and 56 years of age while a different pattern was shown for the age intervals 18-32 and 57-68 years. Also, the rate of bone loss increased with increasing initial bone loss. This was less evident in the oldest age group. It was concluded that the progression of bone loss in the present material is consistent with a "burst" theory. However, the progression did not occur randomly with regard to previous loss of alveolar bone and time.  相似文献   
1000.
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   
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