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991.
992.
Several physiological studies have shown that the subcommissural organ (SCO) is influenced by catecholamines. This study provides immunohistochemical evidence for a noradrenergic input to the SCO of rats. A light plexus of tyrosine hydroxylase (TH)-and dopamine-β-hydroxylase (DβH)-positive axons present in the SCO of both Long-Evans and Sprague-Dawley rats. The innervation density was greatest in the hypendmyal wing of the rostral aspect of the SCO and it declined both caudally in the hypendymal wing and medially in the hypendymal layer. Some TH- and DβH-immunoreactive fibers entered the lateral margin of the ependymal layer along the basal surface of ependymal cells; others coursed medially in the transverse plane to ramify along the base of the ependymal cells. These fibers are presumed to be noradrenergic because phenylethanolamine N-methyltransferase immunoreactivity was absent in adjacent sections through the SCO. Considering the potential role of the SCO region in sodium homeostasis, these data suggest that central noradrenergic input to the SCO may parallel peripheral catecholaminergic mechanisms that regulate sodium balance. 相似文献
993.
The effects of omeprazole 20 and 40 mg twice daily on intragastric acidity in duodenal ulcer patients. 总被引:2,自引:0,他引:2
Savarino V Mela GS Zentilin P Mele MR Vigneri S Mansi C Celle G 《Alimentary pharmacology & therapeutics》1996,10(3):367-372
BACKGROUND: The combination of omeprazole with amoxycillin or clarithromycin is used as treatment against Helicobacter pylori. It seems likely that the antibacterial activity of the antibiotic may be improved by increasing gastric pH towards neutrality, and a twice daily regimen of omeprazole is probably needed. AIM: To assess the effects of twice daily administration of omeprazole 20 and 40 mg. METHODS: Twelve duodenal ulcer patients in remission were randomized to receive in single-blind fashion either placebo, omeprazole 20 mg or omeprazole 40 mg twice daily (08.00 and 20.00 h). On the sixth day of dosing they underwent 24-h gastric pH-metry. RESULTS: Omeprazole 20 and 40 mg b.d. produced marked decreases (P < 0.001) of 24-h gastric acidity (pH 5.4 +/- 0.9 and pH 5.7 +/- 0.6, respectively, vs. a basal pH of 1.4 +/- 0.2) and kept gastric pH at levels higher than 3.0 for almost 24 h. Gastric pH was kept above 5.0 for about 18 h and above 6.0 for about 10 h, while the time spent above 7.0 did not exceed 3 h. There were no significant differences between the two omeprazole dosages at any pH threshold. CONCLUSION: Omeprazole 20 mg b.d. is sufficient to render the gastric milieu as anacidic as possible in duodenal patients. 相似文献
994.
Starling MR; Dehmer GJ; Lancaster JL; Lasher JC; Walsh RA; Weiland FL; Uhl GS; Blumhardt R 《Radiology》1985,157(1):231-237
Normal quantitative circumferential profile limits were established for a 30 degrees bilateral rotating slant-hole (RSH) collimator tomographic system. This system's value in detecting segmental coronary artery disease was assessed in a study evaluating 196 patients by thallium 201 myocardial scintigraphy and coronary arteriography. Profile curves were calculated from images of 20 healthy patients and used to identify significant coronary artery disease (greater than or equal to 70% diameter narrowing) in the left anterior descending (LAD), the right, and the left circumflex (LCx) coronary arteries. In a group of 86 patients, an abnormality on the apical or middle plane optimally identified segmental coronary artery disease. When such abnormalities were prospectively evaluated in a test group of 110 patients, the sensitivity and specificity were 79% and 93% for LAD, 90% and 90% for right, and 83% and 83% for LCx coronary artery disease. Compared with qualitative interpretation of the planar and tomographic images, quantitative tomography significantly improved the sensitivity of T1-201 imaging in detecting LAD, right, and LCx coronary artery disease (P less than .001) in patients with or without previous myocardial infarction. 相似文献
995.
MR Dr. B. von Boros 《Annals of hematology》1968,17(5):300-301
Zusammenfassung Die qualitative Prüfung des Immunoglobulin-G-Gehaltes durch Agargel-Präzipitation erlaubt die Vermeidung von falschen Ergebnissen bei den Gm-und Inv-Bestimmungen.
Summary The qualitative examination of immune-globulins-G by agar-precipitation prevents erroneous determinations of Gm- and Inv-groups.
Résumé Un examination qualitative des immune-Globulines-G par precipitation en milieu de Gelose (Agar) permets la prévention des résultats faux chez groupages Gm et Inv.相似文献
996.
Saralasin, an angiotensin II receptor antagonist, is ineffective in reducing drinking after water-deprivation (WD). Angiotensin III has considerable dipsogenic potency. It may be formed without angiotensin II as an intermediate. To clarify whether angiotensin III formation masks a role for angiotensin in WD, 48 hr WD rats were infused via a lateral cerebroventricle with a) CSF, b) Saralasin, c) SQ 20,881, a converting enzyme inhibitor, or d) Saralasin + SQ. No drug effect on drinking was observed. The results demonstrate that angiotensin III is not required for WD drinking. 相似文献
997.
Gatenby RA; Hartz WH; Engstrom PF; Rosenblum JS; Hammond ND; Kessler HB; Moldofsky PJ; Clair MR; Unger E; Broder GJ 《Radiology》1987,163(1):172-175
Photodynamic therapy was performed on ten tumors in patients who did not respond to initial therapy and for whom no additional conventional therapy was available. A sensitizing agent (hematoporphyrin derivative [HpD]) was injected directly into each tumor under computed tomographic (CT) guidance to deliver high concentrations to the tumor and to minimize systemic toxicity. Three to 6 days after the injection, a clear Teflon sheath catheter was placed into the tumor under CT guidance. The tumor was exposed to red light (630-nm wavelength) through laser fiberoptics inserted in the sheath. The initial investigation confirmed the technical feasibility of CT-guided photodynamic therapy by means of intratumoral HpD injections and laser exposure through fiberoptics inserted in sheath catheters. The toxicity from a single treatment was minor, and the tumor response was encouraging. 相似文献
998.
MR Prof. Dr. S. Hensel 《Journal of orofacial orthopedics》1990,51(5):266-270
Zusammenfassung In einer experimentellen Studie wurde an Patienten mit ausgeprägten frontalen Dysgnathiesymptomen und deutlichen Abweichungen von den Kriterien einer optimalen dynamischen Okklusion die Kiefergelenkfunktion untersucht. Mit Hilfe eines Meßplatzes zur simultanen, kontaktlosen Registrierung von Mundöffnungs- und Schließbewegungen und Geräuschen des Kiefergelenkes konnten im Vergleich zu einer eugnathen, gleichaltrigen Kontrollgruppe keine wesentlichen Einschränkungen der Kiefergelenkfunktion festgestellt werden.
Nach einem Vortrag, gehalten anläßlich der Jahrestagung der Deutschen Gesellschaft für Kieferorthopädie, Heidelberg 6. bis 10. 6. 1990. 相似文献
Summary In an experimental study we examined the function of the TMJ of patients with a considerable aberration from ideal dynamic occlusion and with obvious symptoms of frontal dysgnathia. Using a measuring seat for the simultaneous recording of opening- and closing movements without occlusal interference and the sounds produced by the TMJ, we could not find any significantly impaired TMJ function compared with an orthognathic control group of similar age.
Nach einem Vortrag, gehalten anläßlich der Jahrestagung der Deutschen Gesellschaft für Kieferorthopädie, Heidelberg 6. bis 10. 6. 1990. 相似文献
999.
1000.
血管紧张素Ⅱ及牛磺酸对体外培养乳鼠肥大心肌细胞心律失常发生的作用 总被引:2,自引:0,他引:2
在培养72h的乳鼠心肌细胞,血管紧张素Ⅱ(angiotensinⅡ,AgnⅡ)1,10,100和1000nmol·L-1时,可浓度依赖性地增加细胞搏动频率;而牛磺酸5,10和20mmol·L-1不影响心肌细胞搏动频率,但能浓度依赖性地拮抗AngⅡ100nmol·L-1加快心肌细胞搏动频率的作用。AngⅡ100nmol·L-1连续作用7d引起的培养乳鼠肥大心肌细胞搏动频率加快,动作电位APA升高,APD50和APD90延长,SCL缩短;哇巴因50nmol·L-1诱发的心肌细胞搏动节律失常发生率高于常规培养组。牛磺酸20mmol·L-1可抑制AngⅡ引起的上述改变,并降低哇巴因诱发的心律失常发生率。 相似文献