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21.
Objective: To elucidate the effects of exogenous basic fibroblast growth factor ( bFGF ) on biological characteristics of rat osteoblasts cultured in vitro. Methods: The osteoblasts isolated from a Sprague-Dawley rat and cultured in vitro were treated with different concentrations of bFGF ( 5-50 ng/ml) respectively. At 24 hours after treatment, the proliferating cell nuclear antigen was measured with immunocytochemistry, alkaline phosphatase (ALP) activity was determined and the expression of transforming growth factor beta 1 ( TGF-β1 )was detected to observe the effects of bFGF on growth and differentiation of osteoblasts. Resu/ts: bFGF ( 5-50 ng/ml ) could obviously promote the growth of osteoblasts. The intracellular expression of TGF-β1 mRNA increased significantly, but the intracellular ALP content decreased. Conclusions: bFGF can obviously stimulate the proliferation of osteoblasts and promote the synthesis of TGF-β1, but cannot promote the differentiation of osteoblasts.  相似文献   
22.
创面异体移植培养表皮细胞后存活的判定   总被引:1,自引:0,他引:1  
应用4种方法判定烧伤创面异体移植的培养表皮细胞存活情况:1.聚合酶链反应(PCR)查Y染色体特异性DNA片段;2.PCR扩增PMCT118长度多态性基因位点;3.PCR/SSOHLA-DQa分型;4.DNA指纹。共检测16例病人的27个活检标本,均证实有供者的DNA,最长时间为移植后92天。初步实验结果表明:培养表皮异体移植后可存活较长时间。  相似文献   
23.
Pseudorabies virus glycoprotein E (PRV gE) has been recognized as a suitable diagnostic antigen for pseudorabies. In order to produce gE antigen in large quantities and at low cost, a gene fragment encoding PRV gE epitopes was expressed in Pichia pastoris expression system. SDS-PAGE and Western blotting revealed that the expression product was two recombinant proteins, approximately 38 and 32 kDa, in the culture supernatant of P. pastoris integrant 72 h after induction. Protein concentration assay showed the expression product amounted to 106.7 mg/l, accounting for 66.67% of total culture supernatant proteins. An indirect PRV gE-ELISA was then established by using the recombinant expression product as a coating antigen. Cross-reactivity assay showed that this antigen was PRV specific. Reproducibility experiment displayed good consistency. Comparison of detection results of 348 field serum samples between PRV gE-ELISA and a commercially available PRV diagnostic kit showed there was no significant difference between these two methods (P > 0.05).  相似文献   
24.
The assumption of Hardy-Weinberg equilibrium (HWE) among alleles is of fundamental importance in genetic studies. There are numerous testing methods for it using genotype counts data. The exact test is used when the sample size is not large enough for asymptotic approximations. There are several numerical methods to carry out this test, such as complete enumeration, Monte Carlo and Markov chain Monte Carlo simulations. Complete enumeration is impractical in many applications, especially when the table counts are large. The Monte Carlo method is simple to use but still difficult when the table counts become large. The Markov chain Monte Carlo method, by sampling a sub-table each time, is suitable for this latter situation. Based on switches among a few (no more than four) cells, the existing Markov chain samplers are highly dependent and inefficient for large tables. Here we consider a new Markov chain sampling, in which a sub-table of user-specified size is updated at each iteration. The resulting chain is less dependent, and the sampling is flexible and efficient. The conventional test for HWE is based on a few test statistics, such as the likelihood and the chi-squared statistic. To expand the family of test statistics, we consider a class of divergence measures for the departure of HWE. Examples are given as illustrations.  相似文献   
25.
目的通过分析脑死亡判定自主呼吸激发试验(AT)的质控指标,探讨改进策略,提高AT的实施率和完成率。方法收集吉林省脑损伤质控中心2017年-2020年脑死亡判定病例相关资料,依据标准进行AT技术质控,分析AT实施率和完成率情况。结果AT实施率由2017年的4.3%提升至2020年的83.5%;完成率由2017年的66.7%提升至2020年的96.1%。实施AT后可出现严重酸中毒、低血压、低血氧、低血钾等风险,未实施AT和未完成AT的原因主要为血压、心率、血氧不稳定。结论通过医师间、医护间的技术合作,有利于提升实施AT的安全性。为进一步提升AT实施率和完成率,建议制定出现AT相关心跳骤停情况的不苛责机制,健全AT相关培训及考核制度。  相似文献   
26.
Objective: To establish a high-performance liquid chromatographic method (HPLC) for the simultaneous determination of sixteen compounds from Artemisia ordosica. Methods: HPLC was used to analyze 16 quality indicators of A. ordosica. The HPLC conditions were as follows: Agilent Eclipse Plus C18 column (250 mm × 4.6 mm, 5 μm) with acetonitrile (A)-water (B) as mobile phase, gradient elution: 0?10 min, 75%?65% B; 10?30 min, 65%?35 % B; and finally 30?40 min, 35%?15% B. The flow rate was 1.0 mL/min, the column temperature was 40 °C, the injection volume was 10 μL, and monitored by absorbance at 285 nm for compounds 1?10, 12 and 225 nm for compounds 11, 13?16. Results: Under the selected experimental chromatographic conditions, compounds 1?16 showed good linearity (r > 0.9993) in a wide concentration range. Their average recoveries were 99.50%, 95.38%, 97.75%, 96.00%, 98.20%, 97.50%, 95.50%, 99.33%, 96.75%, 96.50%, 98.50%, 97.83%, 99.20%, 95.33%, 97.33% and 96.30%, respectively, and the RSD were 1.99%, 1.81%, 1.63%, 1.98%, 1.67%, 1.92%, 1.74%, 1.67%, 1.90%, 1.72%, 1.88%, 1.83%, 1.79%, 1.76%, 1.81% and 1.96%, respectively. Conclusion: Based on the results of the HPLC analysis, it was concluded that p-hydroxycinnamic acid (1), O-hydroxycinnamic acid (2), coniferyl alcohol (5), 5,4''-dihydroxy-7,3''-dimethoxyflavanone (8), 5,4''-dihydroxy-7-methoxyflavanone (9), 5-hydroxy-7,4''-dimethoxyflavanone (12), dehydrofalcarindiol (13), arteordoyn A (14), dehydrofalcarinol (15) and capillarin (16) are best suited for the role of quality indicators of A. ordosica grown in different ecological environments.  相似文献   
27.
出生队列是研究生命早期暴露对健康结局影响的重要工具, 但目前缺乏有力支撑孕前暴露特别是父系暴露对生殖健康和妊娠结局影响研究的大型队列平台。重庆市孕前生殖健康与出生结局队列研究是起始于孕前阶段, 同等关注男女双方的环境、心理、行为等暴露因素对生殖健康和不良妊娠结局影响的前瞻性队列研究。项目于2019年正式启动, 计划招募有生育意愿的育龄夫妇20 800人。通过随访, 调查志愿者2年内是否自然受孕。对进入妊娠期的女性志愿者, 在孕早、中、晚期进一步随访, 并对分娩的子代随访至2岁, 监测早产、低出生体重、出生缺陷、神经功能发育障碍等结局发生情况。各阶段分别采集相应的数据信息和生物样本, 包括精液、外周血、尿液、胎盘、脐带、脐带血、口腔拭子等。截至2022年1月, 已纳入志愿者8 698人, 分布于重庆市所有38个区/县。本队列建设目标是成为涵盖父母双方的前瞻性大样本孕前出生队列, 将以独特的设计和更加全面的视角阐明全生育周期特别是孕前期暴露因素对生殖健康和不良出生结局的影响及机制。  相似文献   
28.
烧伤后血清触珠蛋白对T淋巴细胞功能的影响   总被引:2,自引:2,他引:2  
采用亲和层析法从烧伤血清纯化触珠蛋白(Haptoglobin,HP)后,体外观察了纯化HP对正常小鼠胸腺细胞在conA刺激下增殖与IL-2产生及对IL-2诱导的IL-2依赖细胞株(CTLL-2)增殖的影响。结果表明,纯化HP在相当于烧伤血清HP浓度时,对小鼠胸腺细胞增殖、IL-2产生及CTLL-2增殖具有非常明显的抑制作用;但在相当于正常血清HP浓度时纯化HP则无抑制作用。提示烧伤血清高浓度的HP可能是烧伤后T淋巴细胞免疫功能低下的一个重要原因。  相似文献   
29.
Cadmium(Cd),one of the most dangerous heavy metals,has a very similar ionic radius to calcium(Ca),The interference of cadmium in calcium homeostasis may play an important role in cadmium toxicity.Recent reports indicate that calmodulin(CaM) inhibitors such as trifluoperazine and chlorpromazine(CPZ) could protect rodents against cadmium toxicity,It was also reported that pretreatment of mice with zine(Zn)could reduce the adverse effects induced by cadmium.The aim of this study is to determine whether Cd changes the balance of other essential metals such as Zn and copper(Cu) in rat tissues,and whether CPZ can reverse these changes which are induced by cadmium intoxication.Adult male Sprague-Dawley(SD) rats were injected intraperitoneally(ip) with cadmium chloride(CdCl2)(0.2,0.4,0.8mg Cd/kg body wight) alone and 0.4mg Cd/kg in association with CPZ(5mg/kg) daily for a week.The control animals were injected with normal saline only.The results showed that the cadmium content in the liver,kidney,and testis increased significantly with a dose-response relationship.Cadmium treatment markedly increased the Zn and Ca content in some of the tissues,Hepatic and renal metallothionein(MT) increased significantly after cadmium intoxication,CPZ treatment,howerver,reduced cadmium content in liver,but not blood and kidney.CPZ seemed to decrease the content of MT in liver and significantly increase the amounts of MT in kidney.These data suggest that the intervention of cadmium with tissue essential metals may play a role in cadium toxicity in rats,and calmodulin inhibitors to some extent can reduce the adverse effect of cadmium by decreasing the cadmium load in tissues and reversing the unbalance of essetial metals.  相似文献   
30.
烟雾吸入伤后肺泡上皮液体清除机能的变化及其意义   总被引:1,自引:0,他引:1  
观察烟雾吸入伤后肺泡上皮液体清除功能的变化及其意义。方法 :Wistar大鼠 4 2只 ,随机分为正常对照组 (C组 )、烟雾致伤组 (I组 )、阿咪洛利组 (A组 )、哇巴因组 (O组 )、阿咪洛利加哇巴因组 (AO组 )和特普他林组 (T组 )。采用大鼠烟雾吸入伤模型。伤后 2 4h测定肺泡内液体清除率 (ALC)、总肺水量 (TLW )和肺血管外肺水量 (EVLW )。结果 :I组ALC降低 4 6.8% ,TLW和EVLW进一步增加 ;AO组ALC则降至最低点 ,TLW和EVLW升至最高点。而T组ALC明显增高 ,TLW和EVLW显著减少。ALC与TLW和EVLW之间显著相关。结论 :肺泡上皮液体清除功能障碍是烟雾吸入伤后早期肺水肿形成的因素之一。  相似文献   
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