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101.
Liu J Zheng BS Aposhian HV Zhou YS Chen ML Zhang AH Waalkes MP. 《Journal of the peripheral nervous system : JPNS》2002,7(3):208-208
Optimization of a previously disclosed sorbitol dehydrogenase inhibitor (SDI, II) for potency and duration of action was achieved by replacing the metabolically labile N,N-dimethylsulfamoyl group with a variety of heterocycles. Specifically, this effort led to a series of novel, in vitro potent SDIs with longer serum half-lives and acceptable in vivo activity in acutely diabetic rats (e.g., 62, 67, and 69). However, the desired in vivo potency in chronically diabetic rats, ED90 less than or equal to 5 mg/kg/day, was achieved only through further modification of the piperazine linker. Several members of this family, including 86, showed better than the targeted potency with ED90 values of 1-2 mg/kg/day. Compound 86 was further profiled and found to be a selective inhibitor of sorbitol dehydrogenase, with excellent pharmacodynamic/pharmacokinetic properties, demonstrating normalization of sciatic nerve fructose in a chronically diabetic rat model for approximately 17 h, when administered orally at a single dose of 2 mg/kg/day. 相似文献
102.
S Paeschke N Horn C Fotopoulou A Zambon-Bertoja A Sollwedel ML Zenclussen P Casalis J Dudenhausen HD Volk F Chen A Zenclussen 《American journal of reproductive immunology (New York, N.Y. : 1989)》2005,54(2):120-121
The acceptance of the semiallogeneic fetus within the maternal environment requires tolerance mechanisms not fully characterized yet. Normal pregnancy is known to be associated with a Th2 profile. Furthermore, T-regulatory cells were proposed to regulate the Th2/Th1 balance at early stages of pregnancy. Treg may avoid the shift to a Th1 profile preventing miscarriage. Accordingly, spontaneous abortion is characterized by a Th1 dominance and diminished levels of Tregulatory cells (Treg). The major aim of the present work was to investigate if pre-eclampsia, a late immunological complication of pregnancy, is characterized by similar hallmarks. Therefore, we measured the surface antigens CD4, CD25, CD8, CTLA4 (as well as the secretion of IL-10) in peripheral blood from patients suffering from pre-eclampsia (n = 8) and age-matched patients undergoing normal pregnancies (n = 9) by 4-colour flow-cytometry. We were not able to find any significant differences in the levels of CD4+ , CD25+ , CD8+ , CTLA4, CD4+ /CD25+ , CD4+ /CD25bright , CD4+ /CTLA4, CD25+ /CTLA4, CD4+ /CD25+ /CTLA4, CD8+ /CD25+ , CD8+ /CTLA4 or CD8+ /CD25+ /CTLA4 cell subsets. Our data suggest that Treg may not participate in the onset of pre-eclampsia and suggest other regulatory mechanisms during late pregnancy. 相似文献
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Childhood scoliosis: MR imaging 总被引:2,自引:0,他引:2
Nokes SR; Murtagh FR; Jones JD d; Downing M; Arrington JA; Turetsky D; Silbiger ML 《Radiology》1987,164(3):791-797
The spinal cords of 28 scoliosis patients between the ages of 1 month and 17 years were examined with magnetic resonance (MR) imaging. Complete visualization was obtained in all cases. In 15 patients (53%) neuropathologic abnormalities demonstrated by MR imaging significantly affected their clinical course, including tethered cords (n = 7), syringomyelia (n = 5), Arnold-Chiari I malformation (n = 4), spinal cord tumors (n = 2), Arnold-Chiari II malformation (n = 3), and diastematomyelia (n = 1). The advantages of MR imaging in the evaluation of the scoliotic spine in children include a high sensitivity for the occult conditions associated with scoliosis, good anatomic demonstration of the cord, and absence of bone artifacts. MR imaging is recommended as a primary imaging modality in scoliosis, following conventional radiography. 相似文献
107.
Cyano and amidino flavans, isoflavans and 3(2H)-isoflavenes were synthesized in order to study their in vitro antirhino-virus activity, by comparison with the known corresponding chloro derivatives. The activity of the new compounds was evaluated on rhinovirus 1 B infected HeLa cell cultures by examining their ability to interfere with viral cytopathic effect and with plaque formation. It was found that generally the cyano derivatives behave like the chloro compounds, whereas the amidino derivatives show a lower activity, although always dependent on the position of substituent. 相似文献
108.
Digital imaging of the chest 总被引:4,自引:0,他引:4
Fraser RG; Sanders C; Barnes GT; MacMahon H; Giger ML; Doi K; Templeton AW; Cox GG; Dwyer SJ d; Merritt CR 《Radiology》1989,171(2):297-307
During the past several years, image acquisition in nuclear medicine, computed tomography, ultrasonography, subtraction angiography, and magnetic resonance has been by digitization. Despite these advances, research in the development of digital imaging in conventional radiography has lagged behind. Although studies with a variety of digital techniques have been carried out on several fronts, we still do not possess a method that has captured the imagination of the majority of radiologists and other physicians to a point where it could replace conventional screen-film imaging. This article reviews the current status and general principles of the technology, focusing on the four digital radiographic techniques that have shown the greatest promise - film digitization, an image intensifier - based system, photostimulable phosphor plates, and a scanned projection system. The physical aspects of each of the four systems and the clinical results that have been reported to date, as well as the advantages and disadvantages of each system, are presented. 相似文献
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110.
目的:观察单独和配合补充肉碱和糖对大鼠红细胞流变性及抗运动疲劳能力的影响。方法:实验于2005-09/11于河北师范大学体育学院运动生理学实验室完成。①选用SD雄性大鼠72只,按随机数字表法分为4组:安静组(n=6)、安静补服组(n=18)、安慰运动组(n=12)和补服运动组(n=36)。安静补服组和补服运动组均给予3种药物形式:左旋肉碱(由沈阳东宇精细化工有限公司生产)、葡萄糖(济南利民制药有限公司生产)、肉碱和葡萄糖。安静补服组和补服运动组每天上午8∶30给予自来水溶解的肉碱和/或糖补剂,安静组和安慰运动组给予相同量的自来水。连续补充7d,补服量:肉碱组、葡萄糖组、肉碱 葡萄糖组分别为650mg/(kg·d),7g/(kg·d),325mg/(kg·d) 3.5g/(kg·d)。②在实验第8天,将安静组取血4mL。安慰运动组和补服运动组进行无负重游泳至力竭,然后取血。采用北京泰诺德新技术研究所生产的BV-100型无摩擦式血液流变仪测全血高切黏度(180s-1)、全血高切还原黏度(180s-1)、全血低切黏度(3s-1)、全血低切还原黏度(3s-1)、刚性指数及聚集指数。③计量资料进行正态分布、方差齐性检验后,再进行方差分析。结果:大鼠72只均进入结果分析。①红细胞流变性指标变化:安静补服组各组虽大部分红细胞流变性指标有改善,但与安静组相比,差异无显著性意义(P>0.05)。安慰运动组运动后5min全血高切黏度和全血高切还原黏度明显高于安静组(P<0.01),运动24h后全血高、低切黏度和红细胞聚集指数明显高于安静组(P<0.01)。一次力竭运动后5min各补服运动组全血低切黏度明显低于安慰运动组(P<0.01)。各组间红细胞刚性指数和红细胞聚集指数差异不明显(P>0.05)。各补服运动组间相比,补服肉碱组的全血低切还原黏度最高(P<0.01)。各补服运动组运动后24h全血低切还原黏度和红细胞聚集指数明显低于安慰运动组(P<0.05~0.01),补服肉碱和肉碱 葡萄糖运动组全血低切还原黏度和全血低切黏度、红细胞聚集指数明显高于补服葡萄糖运动组(P<0.05~0.01)。②抗疲劳作用:补服肉碱、葡萄糖、肉碱 葡萄糖运动组大鼠游泳时间分别为(334.5±27.81),(321.0±51.83),(326.5±39.9)min,均长于安慰运动组[(252.5±42.69)min,P<0.01];各补服运动组间差异不明显(P>0.05)。结论:单独补充或合用肉碱和糖均有利于力竭运动后大鼠红细胞流变性指标的改善,导致其运动能力的提高。 相似文献