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排序方式: 共有5969条查询结果,搜索用时 15 毫秒
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A Sharma H L Goh N Asokananthan A Bakker G A Stewart H W Mitchell 《The European respiratory journal》2006,27(1):20-28
Mucosal trypsin, a protease-activated receptor (PAR) stimulant, may have an endogenous bronchoprotective role on airway smooth muscle. To test this possibility the effects of lumenal trypsin on airway tone in segments of pig bronchus were tested. Bronchial segments from pigs were mounted in an organ chamber containing Kreb's solution. Contractions were assessed from isovolumetric lumen pressure induced by acetylcholine (ACh) or carbachol added to the adventitia. Trypsin, added to the airway lumen (300 microg x mL(-1)), had no immediate effect on smooth muscle tone but suppressed ACh-induced contractions after 60 min, for at least 3 h. Synthetic activating peptides (AP) for PAR1, PAR2 or PAR3 were without effect, but PAR4 AP caused rapid, weak suppression of contractions. Lumenal thrombin was without effect and did not prevent the effects of trypsin. Effects of trypsin were reduced by N(omega)-nitro-L-arginine methyl ester but not indomethacin. Trypsin, thrombin and PAR4 AP released prostaglandin E2. Adventitially, trypsin, thrombin and PAR4 AP (but not PAR2 AP) relaxed carbachol-toned airways after <3 min. The findings of this study show that trypsin causes delayed and persistent bronchoprotection by interacting with airway cells accessible from the lumen. The signalling mechanism may involve nitric oxide synthase but not prostanoids or protease-activated receptors. 相似文献
3.
C. Sch?fer H. H. Klünemann B. Ibach J. Mueller A. Putzhammer I. Trender-Gerhard G. Schuierer H. E. Klein 《Der Nervenarzt》2002,24(1):879-882
Wir berichten über den ersten Fall von polyzystischer lipomembran?ser Osteodysplasie oder “brain, bone and fat disease” in
Deutschland. Die nach dem Erstbeschreibern auch als Morbus J?rvi-Hakola-Nasu bezeichnete Erkrankung ist bisher vor allem in
Japan und in Finnland beschrieben worden. Einzelne F?lle wurden aus Schweden, Norwegen, Italien, Südafrika, Belgien und den
USA berichtet. Im deutschsprachigen Raum ist bisher ein Fall aus ? ver?ffentlicht worden. 相似文献
4.
Effect of oxygen withdrawal on active and passive electrical properties of arterially perfused rabbit ventricular muscle 总被引:1,自引:0,他引:1
Oxygen withdrawal from myocardial cells leads to changes of the transmembrane action potential (mainly action potential shortening), to cellular uncoupling, and to changes of vascular permeability. This study was aimed at the simultaneous measurement of electrical activity and passive electrical properties (extracellular and intracellular longitudinal resistance) in arterially perfused rabbit papillary muscles under different conditions of changed oxygen supply. These included 1) complete anoxia (erythrocyte-free perfusate), 2) hypoxia (PO2 between 23-28 mm Hg, erythrocytes present) in the presence and absence of glucose, and 3) normoxia with erythrocyte-free perfusate. Similarly to myocardial ischemia, rapid cellular uncoupling occurred only after an initial stable period of approximately 17 minutes, and it required complete anoxia. The marked shortening of the action potential developed before cellular uncoupling. In six out of eight experiments, the fibers were inexcitable when uncoupling started. In severe hypoxia, no significant change of internal longitudinal resistance was observed over 35-40 minutes. The time course of the extracellular longitudinal resistance was different from the change in intracellular resistance: A marked decrease occurred almost immediately after the onset of oxygen withdrawal. This decrease was followed by a small increase in conduction velocity, which was most likely due to a change in the interstitial compartment (edema). It was observed during anoxic as well as during hypoxic perfusion. We conclude that 1) cellular uncoupling in arterially perfused tissue requires almost complete oxygen lack and occurs with a delay of more than 10 minutes, 2) marked action potential shortening precedes uncoupling, and therefore can not simply be attributed to an increase in free, intracellular calcium, and 3) vascular endothelial function is more sensitive to oxygen withdrawal than the myocyte. 相似文献
5.
A total of 106 vascular reconstructions below the inguinal ligament including axillo-femoral and femoro-femoral bypasses were performed using 137 Dardik's human umbilical veins. The indication for surgery was limb salvage in 29%. The distal anastomosis was done with the popliteal artery above the knee in 53 cases, below the knee in 31, and with a tibial artery in 1. The axillo-femoral bypass was performed in 21 cases, and femoro-femoral bypass in 32. The accumulated graft patency rates of femoro-popliteal bypass at 1 yr./3 yrs./5 yrs. were 93%/75%/75%, those of femoro-femoral bypass were 85%/85%/85%, and those of axillo-femoral bypass were 54%/27%/27%. No special risk factor influencing patency rate was found from this study. In long term period, graft aneurysm was observed in 3 cases. It is concluded that the human umbilical vein is the graft material of choice for femoro-popliteal or femoro-femoral bypass when the saphenous vein is not available, and the careful follow-up is important because of the risk of graft aneurysm. 相似文献
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Pars plana vitrectomy in chronic uveitis 总被引:1,自引:0,他引:1
R Kl?ti 《Klinische Monatsbl?tter für Augenheilkunde》1988,192(5):425-429
Statistical analysis of 54 eyes with chronical endogenous uveitis, mostly juvenile, treated with simple or combined pars plana vitrectomy. Most striking is the high frequency of localized or combined cyclitis with good functional results, although complications of the disease (retinal detachment, vasculitis, PVR, macular damage) are extremely frequent in cyclitis, and this group also includes, three cases of postoperative phthisis. The best argument in favor of an chronic uveitis is the fact that an overwhelming majority of the patients were able to switch from rigorous systemic preoperative medication to simple eye drops or no treatment at all. 相似文献
9.
This study aimed at investigating the direct effects of two low osmolality radiographic contrast media, iohexol (non-ionic) and ioxaglate (ionic), on transmembrane action potentials, contractile force and refractoriness of isolated rat atrial preparations. Superfused with 10% solution, ioxaglate induced a biphasic mechanical response, initially decreasing and thereafter increasing contractile force. The same concentration of iohexol only increased contractile force. The two contrast media increased the resting membrane potential, action potential amplitude and rate of depolarization to the same extent. Iohexol prolonged repolarization. Both contrast media decreased the effective refractory period. The direct effects of contrast media on myocardial contractility in this study can explain the different haemodynamic effects of iohexol and ioxaglate in vivo. The observed effects on the action potentials in vitro can explain commonly observed ECG changes during coronary arteriography. The changes in depolarization, repolarization and refractoriness are probably related to the arrhythmogenic properties of these contrast media. 相似文献
10.
Do ethnicity and gender have an impact on pain thresholds in minor dermatologic procedures? 总被引:3,自引:0,他引:3
Gil Yosipovitch Gregory Meredith Yiong Huak Chan Chee Leok Goh 《Skin research and technology》2004,10(1):38-42
Background and Objectives: The perception of pain is a personal experience influenced by many factors, including genetic, ethnic and cultural issues. Understanding these perceptions is especially important in dermatologic patients undergoing minor surgical operations and who often differ in their pain response to surgical treatments. Little is known about how these differences affect the perception of experimental pain. The purpose of this study was to determine experimental pain perception differences in three distinct East Asian ethnic populations.
Methods: Pain thresholds were examined with a psychophysical computerized quantitative thermal sensory testing device (TSA 2001) in healthy volunteers recruited from three different Asian ethnic groups. Using the methods of limits, experimental pain perception threshold was measured on the forehead and volar aspect of the forearm in 49 healthy subjects. The measurements were then repeated after skin barrier perturbation with adhesive tape stripping of the stratum corneum. All three ethnic groups were analyzed separately with respect to age, gender educational level and skin type.
Results: A total of 20 Chinese, 14 Malay and 15 Indian subjects completed the study. Thermal pain thresholds were similar in all three ethnic groups before and after tape strippings. No significant differences were noted between genders.
Conclusions: Using quantitative sensory thermal testing, we demonstrated that no significant differences in pain occur between different races and genders. 相似文献
Methods: Pain thresholds were examined with a psychophysical computerized quantitative thermal sensory testing device (TSA 2001) in healthy volunteers recruited from three different Asian ethnic groups. Using the methods of limits, experimental pain perception threshold was measured on the forehead and volar aspect of the forearm in 49 healthy subjects. The measurements were then repeated after skin barrier perturbation with adhesive tape stripping of the stratum corneum. All three ethnic groups were analyzed separately with respect to age, gender educational level and skin type.
Results: A total of 20 Chinese, 14 Malay and 15 Indian subjects completed the study. Thermal pain thresholds were similar in all three ethnic groups before and after tape strippings. No significant differences were noted between genders.
Conclusions: Using quantitative sensory thermal testing, we demonstrated that no significant differences in pain occur between different races and genders. 相似文献