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31.
Ronald Rosengart Michael Fishbein George C. Emmanouilides 《The American journal of cardiology》1975,35(1):107-111
Severe pulmonary vascular disease developed 1 year after a Mustard operation in a year old boy with transposition of the great arteries and intact ventricular septum. The possible etiologic factors responsible for the development of pulmonary vascular disease are discussed, and it is suggested that this disturbing late postoperative complication may occur more frequently than is recognized. 相似文献
32.
The relative importance of thrombin inhibition and factor Xa inhibition to the antithrombotic effects of heparin 总被引:4,自引:1,他引:4
The relative importance of antithrombin and anti-factor Xa activities of heparin fractions required to achieve optimal antithrombotic effects is unknown. To study this, we measured the effects of standard heparin, an octasaccharide heparin fraction (anti-factor Xa activity only), and dermatan sulfate (antithrombin activity only) on the prevention of thrombosis and related this to their anticoagulant effects in vivo in rabbits. Thrombosis was measured as the incorporation of 125I- fibrinogen into tissue thromboplastin-induced thrombi using a Wessler- type model. Ex vivo changes in thrombin clotting time (TCT) were used as an index of antithrombin activity, and a chromogenic anti-factor Xa assay was used to measure anti-factor Xa activity. In addition, the ability of the three sulfated polysaccharides to simultaneously inhibit the generation of thrombin activity and to enhance the inactivation of the factor Xa added to initiate thrombin generation in plasma was determined. Standard heparin, in a dose of 10 anti-factor Xa U/kg, inhibited thrombus formation by 90%, prolonged the TCT by two seconds, and resulted in an anti-factor Xa level of 0.32 U/mL. The octasaccharide heparin fraction, in a dose of 10 anti-factor Xa U/kg, inhibited thrombus formation by 41%, had no effect on the TCT, and resulted in an anti-factor Xa level of 0.28 U/mL. Higher doses of the octasaccharide resulted in a further increase in the anti-factor Xa levels but had no further effect on thrombus formation. Dermatan sulfate, in a dose of 500 micrograms/kg, inhibited thrombus formation by 95%, but had no affect on the TCT. These results indicate that the antithrombotic effect achieved by inhibiting factor Xa is limited and that better antithrombotic effects are achieved by heparin or heparin- like substances capable of influencing the inactivation and/or the generation of thrombin. 相似文献
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A Bahrami Y Rassi N Maleki MA Oshaghi M Mohebali MR Yagoobi-Ershadi S Rafizadeh 《亚太热带病杂志(英文版)》2014,4(2):110-114
Objective
To identify the vector(s), the parasite and the species composition of sand flies in the district during May-October 2012.Methods
For reaching our objectives we used polymerase chain reaction of kDNA, ITS1-rDNA, followed by restriction fragment length polymorphism.Results
Two species of Phlebotomus sergenti and Phlebotomus tobbi were the most prevalent among 8 species identified comprising 51.1% and 32.9% respectively. Among the 160 specimens of female sand flies tested by polymerase chain reaction of kDNA, ITS1-rDNA, followed by restriction fragment length polymorphisms, only 1 out of 80 Phlebotomus tobbi (1.25%) were positive to Leishmania infantum parasites.Conclusions
Our finding showed that Phlebotomus tobbi may play as a vector to circulate the parasite of Leishmania infantum among reservoir(s) and human. 相似文献36.
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Chen H Ebner AD Bockenfeld D Ritter JA Kaminski MD Liu X Rempfer D Rosengart AJ 《Physics in medicine and biology》2007,52(19):6053-6072
A portable magnetic separator device is being developed for a proposed magnetically based detoxification system. In this paper, the performance of this device was evaluated via preliminary in vitro flow experiments using simple fluids and a separator unit consisting of one tube and two metal wires, each at the top and bottom of the tube. The effects of the following factors were observed: mean flow velocity U(o) (0.14-45 cm s(-1)), magnetic field strength micro(o)H(o) (0.125-0.50 T), wire size R(w) (0.125, 0.250 and 0.500 mm), wire length L(w) (2, 5 and 10 cm), wire materials (nickel, stainless steel 304 and 430) and tube size (outer radius R(o) = 0.30 mm and inner radius R(i) = 0.25 mm; R(o) = 0.50 mm and R(i) = 0.375 mm; and R(o) = 2.0 mm and R(i) = 1.0 mm). Our observations showed that the experimental results fit well with the corresponding theoretical results from the model we previously developed at a low flow velocity area (for example, U(o) < or = 20 cm s(-1)), strong external magnetic field (for example, > or = 0.30 T) and long wire length (for example, L(w) = 10 cm). The experimental results also showed that more than 90% capture efficiency is indeed achievable under moderate systemic and operational conditions. Pressure drop measurements revealed that the device could work well under human physiological and clinical conditions, and sphere buildup would not have any considerable effect on the pressure drop of the device. The breakthrough experiments demonstrated that a lower flow rate V, higher applied magnetic field micro(o)H(o) and diluted sphere suspension, i.e. lower C(o), would delay the breakthrough. All the results indicate the promise of this portable magnetic separator device to efficiently in vivo sequestrate nano-/micro-spheres from blood flow in the future magnetically based detoxification system. 相似文献