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71.
J. Aronson X. C. Shen R. A. Skinner W. R. Hogue T. M. Badger C. K. Lumpkin 《Journal of orthopaedic research》1997,15(2):221-226
Prior studies of distraction osteogenesis in dog and rabbit models have shown predominantly intramembranous bone formation. Other models of fracture healing normally display mixtures of both endochondral and intramembranous bone formation. We have established a rat model of tibial lengthening that reliably reproduces the pattern of zonal osteogenesis previously observed in dog and rabbit models. A distraction rate of 0.25 mm twice a day with a 0-day latency period produced intramembranous bone with zones of progressive mineralization from collagen. With this protocol, rats bridged the distraction gap with a 25% increase in the tibial bone length. After 20 days of distraction and 50 days of consolidation, the three-point bending stiffness, as a percentage of the contralateral control, reached a level equivalent to that measured in the canine model for a 15% lengthening (28-day distraction and 84-day consolidation). Radiodensitometric analysis of the regenerate bones measured 97% of the unaffected contralateral tibial densities, and mineral analyses demonstrated that calcium and phosphorus levels in the regenerate bone reached 78% of contralateral tibial levels by day 70. We concluded that a rat model of distraction ostegenesis will be useful for a wide range of studies involving rapid intramembranous bone formation. 相似文献
72.
73.
The reversal of diastolic cerebral blood flow has been regarded as a characteristic waveform of brain death and a useful confirming sign. We report 2 patients who had diastolic flow reversal but survived. One, a 1-month-old boy with status epilepticus, had reversal of diastolic cerebral blood flow detected by Doppler ultrasound soon after admission. Reversal disappeared after medical management for increased intracranial pressure and seizure control. He recovered without sequelae. The other, a 6-month-old girl with choroid plexus papilloma, had reversal of diastolic flow during abrupt clinical deterioration. Emergent surgical removal of the tumor was performed and she survived with hemiparesis and psychomotor retardation. Our patients demonstrated that even in the presence of diastolic reversal of cerebral blood flow, prompt and effective treatment can avoid a fatal outcome. 相似文献
74.
目的 探讨 3种类风湿因子 (RF)诊断类风湿关节炎 (RA)、反映病情活动度和疗效的临床意义。方法对关节痛 /关节炎 (A组 )、确诊的RA (B组 )、其它免疫结缔组织病 (C组 )患者和正常人 (D组 )共 6 18例用酶联免疫法进行 3种RF的动态检测并随访观察。结果 4组人群中 3种RF的阳性率和浓度以B组最高 [IgM RF为 92 4 % ,(182 5± 5 1 4 )IU/ml;IgG RF为 6 7 8% ,(2 2 9 7± 75 6 )IU/ml;IgA RF为 78 8% ,(2 35 8± 80 7)IU/ml],组间比较依次为B组 >A组 >C和D组 (均为P <0 0 5 )。B组中高活动期RA患者的 3种RF浓度明显高于其它 3组 (P <0 0 5 ) ,IgM RF和IgA RF在稳定期和低活动期较高活动期均明显降低 (均为P <0 0 5 ) ,而IgG RF变化无显著性。随访 3~ 18个月 ,A组中最后确诊为RA的比率以 3种RF同时阳性者最高 (10 0 0 % ) ,2种RF同时阳性者次之(90 9%~ 93 3% ) ,以单一RF作比较则IgG RF >IgA RF >IgM RF阳性者。结论 早期诊断RA以IgM RF的敏感性最高 ,以IgG RF的特异性最高 ,任何 2种以上RF阳性可提高RA诊断的可靠性 ,RF浓度可作为判断RA活动度及药物治疗效果的指标之一。 相似文献
75.
K. S. Us P. M. Klodt V. S. Kudrin A. Ya. Sapronova R. U. Ostrovskaya M. V. Ugryumov K. S. Rayevsky 《Neurochemical Journal》2007,1(2):138-142
The level of spontaneous and K+-stimulated release of endogenous glutamate was studied in experiments on slices of brain cortex of Wistar rats. Pronounced spontaneous release of the neuromediator and its increase under conditions of stimulation were registered by high-performance liquid chromatography with electrochemical detection. The effect of the nootropic and neuroprotective dipeptide Noopept (GVS-111) on release of glutamate was investigated. The peptide in concentrations of 10?5 and 10?6 M caused a statistically significant decrease in spontaneous and K+-stimulated glutamate release. This effect could be the basis of the neuroprotective action of the peptide, suggesting that further studies of Noopept as neuroprotector are very promising. 相似文献
76.
目的:研究肺癌放射导向手术中肿瘤及正常组织P糖蛋白(P-gp)、Ki-67抗原表达与放射性核素摄取比(T/NT)的关系.方法:采用免疫组化方法和显微图像分析技术,测定32例接受放射导向手术的肺癌病人P-gp和Ki-67抗原表达,分析P-gp和Ki-67的标记指数(LI)与T/NT之间的相关性.结果:P-gp和Ki-67的LI和肺癌病人T/NT之间均有相关性(r=-0.61,P=0.0002; r=0.75,P=0.0001).结论:Ki-67的LI越高(肿瘤增殖越旺盛),T/NT值越高;P-gp阳性的肿瘤,T/NT值较低. 相似文献
77.
Objective: To analyze quantitatively the synergistic and antagonistic effects of combined oxymatrine (OMT) and 5-fluorouracil (5-GU)
on a cell line of human liver cancer (HepG2) with median-effect principle in vitro. Methods: The median-effect principle and MTT method were used in the quantitative analysis of effects of the two drugs. Results: Cytotoxic activity of the individual drugs enhanced as drug concentration increased. As fa=0.41, a CI equal to 1 indicated
additivity; fa<0.41, a CI less than 1 indicated synergy; and fa>0.41, a CI greater than 1 indicated antagonism. The sequence
of administration did not influence the cytotoxic activity of the combined antitumor drugs. The ratio of drug concentration
was a factor that can influence the killing effect. Conclusion: The combined drugs interaction (CI<1) was synergistic at lower concentration and antagonistic at higher concentration. The
ratio of drug concentration is a factor that can influence the killing effect.
Biography: HE Song(1965–), male, doctor of medicine, associate professor, Chongqing Medical University, majors in gastroenterology. 相似文献
78.
探讨小儿短暂性滑膜炎与病毒感染 ,特别是柯萨奇B组病毒 (CVB)感染的关系。方法 :采用酶联免疫吸附试验 (ELISA)对 16 2例小儿髋关节短暂性滑膜炎患儿静脉血和其中的 2 1例关节腔液进行病毒IgM抗体检测 ,柯萨奇病毒B组 (CVB)阳性者进行血清学分型及病毒分离。结果 :在 16 2例静脉血样本中病毒IgM阳性 6 2例 ,占总检数的 38.2 7% ,CVB -IgM2 6例占 16 .0 5 % ,AdV -IgM 19例占 11.73% ,CMV -IgM 10例占 6 .17% ,RSV -IgM 4例占 2 .4 7% ;在关节腔液中检出 9例CVB阳性 ,血清学分型 8例为CVB3,1例为CVB4 ,并分离出 1例CVB3。结论 :CVB和腺病毒 (AdV)是小儿髋关节短暂性滑膜炎感染的主要病毒 ,而且以CVB3为主。 相似文献
79.
V. V. Pisarev N. E. Moskaleva Yu. B. Zverkov L. B. Smirnova V. G. Belolipetskaya Ya. V. Sukhanov 《Pharmaceutical Chemistry Journal》2005,39(2):104-107
A reproducible and sensitive analytical procedure has been developed for the quantitative determination of enalapril and enalaprilat in the blood plasma by high-performance liquid chromatography with mass-spectrometric detection (HPLC/MS). For increasing the sensitivity and reproducibility of analyses, the samples were treated with diazomethane in order to obtain methyl esters of the analyzed compounds. The quantitative determination was carried out using the internal standard method; the internal standard was captopril. The detection was performed in the positive ion mode for ions with m/z = 377 (enalaprilat methyl ester), 391 (enalapril methyl ester), and 267 (captopril methyl ester). Enalapril, enalaprilat, and captopril were isolated from the blood plasma and purified by means of solid-phase extraction. The calibration plot is linear in the concentration range from 0.5 to 200 ng/ml. The detection limits for both enalaprilat and enalapril in the blood plasma are 0.1 ng/ml.__________Translated from Khimiko-Farmatsevticheskii Zhurnal, Vol. 39, No. 2, pp. 49 – 52, February, 2005. 相似文献
80.
I. L. Plikhtyak I. V. Yartseva L. G. Aleksandrova N. Ya. Podkhalyuzina M. N. Preobraznenskaya 《Pharmaceutical Chemistry Journal》1991,25(6):420-422
Translated from Khimiko-Farmatsevticheskii Zhurnal, Vol. 25, No. 6, pp. 57–59, June, 1991. 相似文献