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31.
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   
32.
Reversal of diastolic cerebral blood flow in infants without brain death   总被引:1,自引:0,他引:1  
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   
33.
A limited flip angle gradient-echo 3D volume acquisition imaging protocol for mapping partial pressure of oxygen (pO2) in perfluorocarbon compounds (PFCs) at low field (0.14 T) is presented. The pO2 measurement method is based on the paramagnetic effect of dissolved molecular oxygen (O2) which reduces the PFC 19F T1? Specific objectives related to imaging of PFCs through use of the protocol include improved image signal-to-noise characteristics and elimination of 19F chemical shift artifacts. A parametric Wiener deconvolution filtering algorithm is used for suppression of 19F chemical shift artifacts. Application of the protocol is illustrated in a series of calculated pO2 maps of a gas equilibrated, multi-chamber phantom containing perfluorotributylamine (FC-43). The utility of the protocol is demonstrated in vivo through images of a commercially available perfluorocarbon based blood substitute emulsion containing FC-43 sequestered in the liver and spleen of a rat.  相似文献   
34.
目的 :探讨山东、湖北合欢皮与山合欢皮的内在质量。方法 :用氨基酸自动分析仪和原子吸收分光光度计对山东、湖北合欢皮与山合欢皮的氨基酸及部分微量元素进行分析。结果 :山东、湖北合欢皮与山合欢皮均含大量人体必需氨基酸和微量元素。结论 :为评价产地对合欢皮质量的影响以及合欢皮与山合欢皮的质量差异提供了依据  相似文献   
35.
36.
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   
37.
38.
Serum interleukin-2 receptor (sIL-2R) level, activities of natural killer cell (NK) and lymphokine activated killer (LAK) cells were determined in 60 patients with advanced carcinoma (AC) before and after treatment with Shenmai Injection (SMI), forty healthy persons were taken as non-carcinoma control (NC). The results showed that: Serum sIL-2R level in AC were much higher than those in NC (P<0.05) and activities of NK and LAK cells in AC were much lower than those in NC (P<0.05) before treatment. There was no significant difference among gastric, colonic and lung cancer (P>0.05). After treatment with SMI, it was found that the level of sIL-2R in all patients were obviously lowered (P<0.05) while the activities of NK and LAK cells were signifficantly higher than that prior the treatment (P<0.05). Relevancy was not found between sIL-2R and NK, LAK cells. These data suggested that the immune function was compromised in AC, and SMI has a wide effect of immuno-regulation.  相似文献   
39.
为探讨醇脱氢酶(ADH)基因和醛脱氢酶(ALDH)基因多态性与酒依赖患病的相互关系,用耳血干血痕聚合酶链反应、等位基因特异性寡核苷酸探针方法,检测乙醇代谢酶ADH和ALDH基因型在我国蒙、汉民族酒依赖与非酒依赖者中分布频率。结果显示在酒依赖组(汉族52例,蒙族31例)与正常对照组(汉族48例,蒙族35例)之间:汉族的ALDH2基因型频率与等位基因频率的分布差异有非常显著性(P<0.01),而蒙族则表示为ADH2基因型频率与等位基因频率的分布差异有非常显著性(P<0.01)。这提示汉族酒依赖的发病与ALDH2基因有关,蒙族则与ADH2基因有关。  相似文献   
40.
目的:提高原发性输尿管癌的术前诊断水平。方法:对南京医科大学第一附属医院1989-2002年间收治的31例原发性输尿管癌的临床资料进行回顾性分析。结果:31例中,肉眼血尿22例(71.0%),腰痛11例(35,5%)。B超、静脉肾盂造影(IVU)、CT和逆行造影检查的阳性率分别为输尿管腔内占位4例(13.0%)、输尿管腔内占位3例(11.5%)、膀胱或合并膀胱占位8例(36.4%),输尿管充盈缺损6例(40.0%)。29例患者经手术治疗,其中13例行患侧肾、输尿管、膀胱袖状切除。结论:老年患者反复发作的腰痛及血尿应考虑原发性输尿管癌的可能,造影诊断对本病有较高价值,应作CT及MRU无创检查。  相似文献   
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