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排序方式: 共有4076条查询结果,搜索用时 15 毫秒
1.
2.
Fixation of displaced femoral neck fractures: A comparison between sliding screw plate and four cancellous bone screws 总被引:1,自引:0,他引:1
Frank Madsen Frank Linde Erik Andersen Hanne Birke Inge Hvass Torben D. Poulsen 《Acta orthopaedica》1987,58(3):212-216
In a prospective, randomized trial, 104 consecutive patients with displaced femoral neck fractures were allocated either to fixation with a sliding screw plate or 4 ASIF cancellous bone screws. The patients were reexamined at fixed intervals to determine the time of union. The 2-year-cumulated rate of union was 64 per cent in the plate group and 84 per cent in the screw group. 相似文献
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Claudia Linde Cornelia Löffler Christina Kessler U. Quast 《Naunyn-Schmiedeberg's archives of pharmacology》1997,356(4):467-474
In vascular smooth muscle, openers of ATP-dependent potassium channels (K
ATP channels), such as P1075 (N-cyano-N’-(1,1-dimethylpropyl)-N’’-3-pyridylguanidine), produce relaxation. In this study we have investigated the effects of thiol-modifying agents on the
binding of P1075 and on the 86Rb+ efflux stimulating and vasorelaxant effects of the opener in rat aortic rings. The increase in 86Rb+ efflux induced by P1075 was taken as a qualitative measure of K+ channel opening. The hydrophilic SH-group-oxidizing substance, thimerosal (1 to 100μM), abolished specific binding of [3H]-P1075 with an IC50 value of 7.6±1.2μM; at 30μM, the half time for inhibition was 38min. Two other thiol-oxidizing agents, PMB (4-hydroxy-mercuribenzoic
acid) and DTBNP (2,2’-dithio-bis(5-nitropyridine)), inhibited binding up to 86% and 44%, respectively. The disulphide bond
reducing substance, DTT (1,4-dithiothreitol, 0.1 to 1mM), reduced [3H]-P1075 binding by up to 20% and partially reversed the inhibitory effect of thimerosal. In 86Rb+ efflux experiments, thimerosal (3 to 100μM) concentration-dependently increased basal efflux but inhibited P1075-stimulated
tracer efflux with an IC50 value of 7±1μM. The inhibitory effect occurred with a half-time of approximately 8min and was essentially reversed by DTT.
In rings precontracted with noradrenaline, thimerosal inhibited the vasorelaxant effect in a noncompetitive manner, shifting
the concentration-relaxation curves to the right and reducing maximum relaxation.The data show that oxidation of thiol groups
interferes with the binding of the K
ATP channel opener, P1075; concomitantly, the 86Rb+ efflux stimulating and the vasorelaxant effects are inhibited. Reduction of disulphide bonds by DTT has only minor effects
on the action of P1075. Collectively, the results suggest that intact thiol groups are essential for the functioning of the
KATP channel in rat aorta. The different kinetics governing the inhibition of opener binding and of opener-stimulated 86Rb+ efflux suggest that the SH-groups involved in the two processes differ in their accessibility to thimerosal and/or in their
reactivity.
Received: 7 April / Accepted: 9 July 1997 相似文献
5.
Voltage-Gated calcium channels and nonvoltage-gated calcium uptake pathways in the rat incisor odontoblast plasma membrane 总被引:4,自引:1,他引:3
Odontoblasts participate actively in the transport and accumulation of Ca2+ ions to the mineralization front during dentinogenesis. These cells are known to carry membrane-bound ATP-driven pumps and
Na+/Ca2+ antiports for Ca2+ extrusion, but little is known about Ca2+ influx mechanisms into these cells. It has been shown that the administration of Ca2+ channel blockers in vivo strongly impairs Ca2+ uptake in the mineral phase during dentinogenesis in the rat; the present in vitro study is aimed at further elucidating
odontoblast Ca2+ uptake mechanisms. Dissected rat incisor odontoblasts exhibited a pronounced fluorescence when incubated with a fluorescently-labeled
(STBodipy) dihydropyridine, which is specific for voltage-gated Ca2+ channels of the L-type, and this binding was competitively abolished by nifedipine. As assayed by fluorescence spectrometry,
odontoblast Ca2+ uptake was enhanced by the agonistic dihydropyridine BAYK-8644 (5 μM) as well as by plasma membrane depolarization in a high
K+ (120 mM) medium. The Ca2+ uptake after depolarization was impaired by nifedipine (5 μM). When treated with the Ca2+-ATPase inhibitor cyclopiazonic acid (CPA; 10 μM), a nonvoltage-gated uptake of 45Ca2+ was identified. This uptake was not influenced by nifedipine (20 μM) but was impaired by lanthanum ions (200 μM). A nonvoltage-gated
uptake of Mn2+ into CPA-treated cells could be traced using the fura-2 quenching technique. This CPA-induced Ca2+ flux was not caused by an alteration of the plasma membrane potential, as assayed with di-8-ANEPPS. The results demonstrate
that Ca2+ flux into dentinogenically active odontoblasts occurs through voltage-gated Ca2+ channels of the L-type and by nonvoltage-gated, agonist-sensitive Ca2+ uptake pathways.
Received: 6 November 1995 / Accepted: 21 February 1996 相似文献
6.
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C Bierbaum E S Pieles J vd Linde 《Zeitschrift für die gesamte innere Medizin und ihre Grenzgebiete》1988,43(7):193-195
On the basis of two case discussions the authors deal with the clinical significance of the gastric diverticula. In one case a traction diverticulum near to the cardia was found with simultaneously existing intramural leiomyoma of the wall of the stomach. In a second case a typical congenital diverticulum near to the cardia was concerned. It is referred to diagnostic possibilities, differential diagnostic questions and therapy. 相似文献
9.
Logistic regression was used to analyze the influence of pretransplant herpesvirus antibodies, in both patients and donors, on the development of acute graft-versus-host disease in 111 consecutive HLA-identical bone marrow recipients. In bivariate analysis, recipient seropositivity for cytomegalovirus (P = 0.01), donor seropositivity for herpes simplex virus (P = 0.02), and low bone marrow cell dosage (P less than 0.05) were associated with a high incidence of grade II-IV acute GVHD. In multivariate analysis the P values were P less than 0.05 for a positive recipient CMV serology and P = 0.07 for a positive donor HSV serology. Positive serology for 1-2 herpes-viruses among recipients or donors both resulted in a 12% incidence of grade II-IV acute GVHD. Positive serology for 3-4 herpesviruses among patients or donors resulted in an incidence of 32% and 38% of acute GVHD, respectively (P less than 0.05). It is concluded that recipient and donor pretransplant herpesvirus immunity can be used to calculate the risk of moderate-to-severe acute GVHD. 相似文献
10.
Four noninvasive rewarming techniques for mildly hypothermic subjects were compared. Seven subjects were cooled in a water bath of 15 degrees C for 2 h to an average esophageal temperature (Tes) of 36 degrees C. Thereafter, the subjects were rewarmed by immersion of the body in a water bath of 42 degrees C (Method 1), the body but not the extremities in water of 42 degrees C (Method 2), only the extremities in water of 42 degrees C (Method 3), or spontaneous rewarming in blankets (Method 4). Method 1 showed the highest rewarming rate in Tes (10.1 degrees C/h) and an afterdrop in Tes of 0.18 degrees C. Method 2 showed the same afterdrop, but a lower rewarming rate (7.5 degrees C/h). In Method 3, the heat uptake of the extremities was too low to rewarm the subjects effectively. The afterdrop and rewarming rate were 0.38 degrees C and 0.8 degrees C/h, respectively. Method 4 had the lowest rewarming rate (0.2 degrees C/h), and an afterdrop (0.14 degrees C) which was not significantly lower than that of Method 1 or 2. Therefore, Method 1 is recommended for rewarming mild hypothermic subjects because of its high rewarming rate and small afterdrop. 相似文献