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21.
Dexamethasone treatment attenuates early seawater instillation-induced acute lung injury in rabbits. 总被引:8,自引:0,他引:8
Ding Xinmin Duan Yunyou Peng Chaosheng Feng Huasong Zhou Pingkun Meng Jiguang Xue Zhiqian Xu Qinzhi 《Pharmacological research》2006,53(4):372-379
There is very little evidence on the value of giving corticoids in cases of seawater drowning induced acute lung injury/acute respiratory distress syndrome (ALI/ARDS). Therefore, this study aimed to investigate whether dexamethasone treatment can attenuate seawater instillation-induced acute lung injury in rabbits. Seawater (4 ml/kg body weight) was instilled into the lower trachea of ventilated, anesthetized rabbits. Then these rabbits were assigned randomly 20 min later to receive intravenous injection of 1mg/kg body weight of dexamethasone (dissolving in 2 ml of normal saline) or 2 ml of normal saline. All animals demonstrated immediate drops in arterial oxygen tension (PaO2) and the total thoracic compliance, which were significantly improved after 2 h of dexamethasone treatment. Histopathological study also indicated that dexamethasone treatment markedly attenuated lung histopathological changes, alveolar hemorrhage and inflammatory cells infiltration with evidence of decreasing of myeloperoxidase (MPO) activity and tumor necrosis factor-alpha (TNF-alpha) concentration in lung tissue. In addition, dexamethasone treatment reduced extravascular lung water and lung epithelial-endothelial barrier permeability, up-regulated the expression of surfactant protein-A (SP-A) and alpha-epithelial Na+ channel, and increased Na+/K+-adenosine triphosphatase (Na+/K+-ATPase) activity and Na+/K+-ATPase-alpha1 protein abundance. Thus, these data indicate that dexamethasone treatment might be of benefit in patients with seawater aspiration-induced ALI. 相似文献
22.
肱骨骨不连的手术治疗 总被引:4,自引:0,他引:4
目的探讨肱骨骨不连的手术治疗方法及疗效。方法1998年12月~2005年5月共收治肱骨骨不连患者25例,均为肱骨骨折内固定术后发生骨不连,其中3例并发骨髓炎,6例合并不同程度肱骨骨缺损,骨缺损长度为3~6cm。骨不连病程8个月~5年。15例行吻合血管游离腓骨移植,10例采用加压交锁髓内针进行肱骨固定并辅以自体骨植骨。结果术后25例均得到随访,时间6个月~6年2个月。吻合血管游离腓骨移植组中移植的腓骨段均与肱骨干形成骨性愈合,平均骨性愈合时间为3.1个月;交锁髓内针组平均骨愈合时间为3.8个月。按Crates和Whittle肩肘关节功能评价标准,腓骨移植组:优9例,良4例,差2例;交锁髓内针组:优5例,良3例,差2例。结论应用加压交锁髓内针辅以自体骨移植对硬化性肱骨骨不连是一种有效的外科治疗方法;对合并骨髓炎、大段骨缺损及严重骨质疏松的肱骨骨不连,采用吻合血管游离腓骨移植可一期进行修复与重建。 相似文献
23.
医学插图的艺术创作 总被引:1,自引:1,他引:0
高平 《中国医学教育技术》2006,20(4):350-352
介绍了医学插图艺术创作的方法:即在依据医学科学内容的基础上,遵循美学规律,运用科学的艺术表现形式,准确、形象、生动地表达出医学科学的深刻内涵,从而实现医学科学与艺术完美结合的创作目标。 相似文献
24.
目的 观察高转换型肾性骨病中骨保护素及其配体 (OPG,RANKL)的表达,并与骨形态计量学指标进行相关分析。 方法 选择10例慢性肾衰尿毒症患者和3例正常人进行髂骨活检术,获得骨组织标本。采用免疫组化方法检测OPG和RANKL蛋白质的表达。采用全自动图像分析系统进行骨组织形态计量学测定。结果 10例慢性肾衰尿毒症患者经骨病理学检查证实均为高转换型骨病,以破骨细胞活化形成骨吸收陷窝伴或不伴骨矿化不全为特点。免疫组化显示尿毒症患者骨组织中以RANKL阳性表达为主。与正常对照相比,RANKL阳性表达细胞数目显著增加,OPG阳性表达细胞数目显著减少。尿毒症患者RANKL的阳性表达细胞数目与骨吸收面积和破骨细胞数目呈显著正相关。结论 高转换型肾性骨病中,PTH的溶骨作用可能是通过OPG/RANKL/RANK系统介导的。 相似文献
25.
目的:探讨生化修饰疗法对晚期恶性肿瘤病人的治疗效果。方法:对57例晚期恶性肿瘤病人采用置管经输注泵输注化疗药物治疗与护理。结果:此法较全身化疗疗效高,毒副作用小。尤其适用于一般状况差又难于耐受全身化疗的晚期消化系统恶性肿瘤病人。结论:生化修饰疗法安全、有效、方便、费用低,值得推广。 相似文献
26.
β-胡萝卜素立体异构体对环磷酰胺处理小鼠免疫功能的比较研究 总被引:3,自引:0,他引:3
就β-胡萝卜素立体异构体对环磷酰胺处理小鼠的免疫功能影响进行了比较研究。结果显示β-胡萝卜素立体异构体对外磷酰胺造成的免疫功能低下具有不同程度的改善作用,提高胸腺和脾脏指数,增强脾脏细胞对刀豆素A(ConA)的反应性和NK活性,血清溶菌酶含量也有所增加。综合各项指标,9-顺式和全反式混合物的作用最明显,提示一定浓度的9-顺式对于提高β-胡萝卜素对机体的总体作用是有一定意义的。 相似文献
27.
28.
Two unique forms of cytochrome P-450 (P-450), designated NMa and NMb, were recently isolated in this laboratory from nasal microsomes of rabbits. In the present study, polyclonal antibodies to the purified nasal cytochromes were prepared. Immunochemical analysis with specific rabbit anti-NMa and sheep anti-NMb antibodies indicated that P-450 isozymes identical to or having a high structural homology with NMa are present in both olfactory and respiratory mucosa, as well as in liver, but NMb was detected only in the olfactory mucosa. Neither form was detected in other tissues examined, including brain, esophageal mucosa, heart, intestinal mucosa, kidney, and lung. The specific occurrence of NMb in the olfactory mucosa was further substantiated by the detection and specific inhibition by anti-NMb of the formation of unique NMb-dependent metabolites of testosterone in olfactory microsomes but not in microsomes from liver or respiratory mucosa. Similar experiments with antibodies to previously purified rabbit hepatic P-450 isozymes indicated that not all of the hepatic cytochromes are expressed in the nasal tissues. Thus, P-450 isozymes structurally homologous to hepatic forms 2, 3a, and 4, but not 3b and 6, were found in the olfactory mucosa. On the other hand, only form 2 was detected in the respiratory mucosa. Immunoquantitation experiments revealed that NMa and NMb are the major P-450 forms in olfactory microsomes, whereas NMa and P-450 form 2 (or its homolog) constitute the major portion of the respiratory nasal microsomal P-450. The level of NMa in the liver is relatively low, accounting for less than 3% of total microsomal P-450 in this tissue. In addition, evidence is provided that NMa is the major catalyst in the dealkylation of two nasal carcinogens, hexamethylphosphoramide and phenacetin, in both olfactory and respiratory nasal microsomes. 相似文献
29.
Zhe-ping HUANG Jian WANG Wei-xiong SHEN Ping HUANG Jia-ke TSO Qing-xiang SHEN 《生殖与避孕(英文版)》2002,13(4)
Objective To identify genes that may be related to embryo implantation Materials & Methods The PCR subtraction technique was applied at implantation and inter-plantation sites on day 4. 5 of pregnancy in mice. Two novel Expressed Sequence Tags (ESTs ), EST8 and EST81 were identified; their expression in tissues was analyzed by Northern blotting, and their full-length cDNAs were synthesized by PCR.Results We found that these two novel ESTs (EST8and EST81) were noticeably expressed in implantation site in the mouse on day 4. 5 of pregnancy. EST8 was expressed at high level in livers and implantation sites of the mice, while at low level in ovaries and inter-plantation sites. EST81 was predominantly expressed in implantation site and ovary, and at low level in all other tissues. Their complete cDNAs, 1 665bp and 1 264 bp respectively, were synthesized by using PCR.Conclusion The two full-length cDNAs were responsible for embryo implantation,and their functions need to be further studied. 相似文献
30.
目的:探讨EB病毒感染与人大肠癌发生的关系。方法:用原位分子杂交法对130例人大肠癌标本中EB病毒小分子RNA片段进行检测。结果:130例标本中有6例(4.48%)癌组织呈阳性反应,其中4例为男性,4例有明显淋巴细胞浸润。结论:EB病毒感染可能与我国部分大肠腺癌的发生有关,肿瘤细胞间质中大量淋巴细胞浸润可能是EB病毒感染的重要病理学特征。 相似文献