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21.
八珍汤对血虚模型小鼠造血调控因子影响的实验研究 总被引:7,自引:0,他引:7
探讨八珍汤对由环磷酰胺引起的小鼠骨髓造血功能抑制的调控作用。采用环磷酰胺致小鼠血虚模型 ,测定八珍汤对骨髓抑制小鼠外周血象及其细胞因子产生的影响。结果表明 ,八珍汤对环磷酰胺所致血虚模型小鼠骨髓细胞有促进增殖作用 ;经八珍汤诱导制备的巨噬细胞、脾细胞、肺条件培养液和骨骼肌条件培养液能促进血虚模型小鼠骨髓细胞增殖 ,促进血虚模型小鼠骨髓基质细胞分泌肿瘤坏死因子 (TNF)。八珍汤对环磷酰胺所致化疗损伤的造血调控作用可能与直接或间接刺激造血微环境的基质细胞分泌正性和负性造血生长因子有关。 相似文献
22.
mPEG表面修饰的PLGA嵌段共聚物的血液相容性评价 总被引:3,自引:0,他引:3
本实验室设计合成了三种不同LA/GA比例的mPEG修饰PLGA(PELGA,含15%mPEG),为了评价它们的血液相容性,我们以硅化玻璃试管为阴性对照,未硅化的试管为阳性对照,参照国际标准(ISO10993)和《中华人民共和国国家标准GB/T16886医疗器械生物学评价》方法进行了体外评价实验。试验包括溶血率实验,血小板黏附实验,动态凝血时间实验,凝血时间实验,血浆复钙时间实验和凝血酶原时间实验等综合评价指标。结果表明,合成材料具有优良的血液相容性,材料制成的纳米粒有望应用于静脉注射。 相似文献
23.
Daniel T.L. Shek Li Zhao Diya Dou Xiaoqin Zhu Chenghan Xiao 《The Journal of adolescent health》2021,68(4):676-682
PurposeThis study examined the prevalence of posttraumatic stress disorder (PTSD) symptoms among adolescents in mainland China under COVID-19. The direct effects of the perceived threat of COVID-19 and positive youth development (PYD) qualities, as well as the moderating effect of PYD qualities on PTSD symptoms, were studied.MethodsFive schools in Chengdu, Sichuan, China, participated in this study. Two waves of data were collected before school lockdown (Wave 1, between December 2019 and January 2020) and after school resumption (Wave 2, between June 2020 and July 2020), respectively. A total of 4,981 adolescents aged above 11 years (Mean age = 13.15, SD = 1.32 at Wave 1, 51.5% girls) completed questionnaires at both waves. Students responded to measures of PYD qualities at both waves and perceived threat and PTSD symptoms at Wave 2.ResultsA total of 517 adolescents (10.4%) could be regarded as having PTSD. Results indicated significant unique main effects of perceived threat (β = .13, p < .001) and Wave 1 PYD qualities (β = ?.16, p < .001) on PTSD symptoms. Besides, results showed a significant moderating effect of PYD qualities in mitigating the negative impact of perceived threat on PTSD symptoms.ConclusionsThis study revealed the protective effect of PYD attributes in reducing the negative influence of traumatic situations such as COVID-19 on adolescent mental health. Results underscore the importance of promoting PYD qualities in adolescents in mainland China via effective PYD programs. 相似文献
24.
目的 :筛选和鉴定人原发性食管癌组织的相关基因 ,揭示食管癌的癌变机理。方法 :用高效、灵敏的荧光mRNA差异显示技术 ,以食管癌及相应的正常食管粘膜组织为对照 ,通过对其基因表达的比较 ,找出差异条带 ,利用ReverseNorthernDotBlot、DNA序列分析和NorthernBlot,并结合mRNA原位杂交技术对被筛片段进行鉴定。结果 :①在实验中分离、鉴定了 74条差异片段 ,其中包括正常组织表达而癌组织中不表达的差异片段 5 4个 ,癌组织中表达而正常组织不表达的差异片段 2 0个。②其中 1个片段C5 7(337bp)在GenBank数据库中没有发现同源的已知基因或片段 ,推测其可能为食管癌相关基因。③经NorthernBlot检测C5 7在癌组织中有表达信号。④原位杂交技术检测C5 7在癌组织中具有较高的阳性表达率 (74% )。结论 :食管癌组织中C5 7可能是新的食管癌相关的候选癌基因 ,它与食管癌的发生发展可能有关 相似文献
25.
Isolation of Nanjing local strains of HHV-7 and their biological and immunological characteristics 总被引:2,自引:0,他引:2
To investigate the biological and immunological characteristics of the Nanjing local strains of HHV-7,fourstrains of herpesvirus were isolated from saliva specimens of one healthy individual and three childrensuffering from a kidney disease in Nanjing.The viruses were identified by transmission electron microscopy(EM),indirect immunofluorescence assay(IFA) with a specific monoclonal antibody;nested polymerase chainreaction,restriction mapping and DNA sequencing.The virus-infected cells showed the typical cytophathiceffect(CPE) under microscopy and could be detected by IFA with the human herpesvirus-7(HHV-7) specificantibody.Under EM,herpesvirus-like and virions capsids could be found in their cytoplasm or nucleoplasm.HHV-7 DNA fragments amplified from infected cells by nested PCR were confirmed by restriction mappingand DNA sequencing.Similarly to DC strain,an known HHV-7 strain used in the present study as the positivecontrol,the virus could be inactivated by ultraviolet irradiation for 10 min,heated at 45℃ for 30 min,pH<5or>9 at 4℃ for 2 h and ether or chloroform for 10 h.The virus induced the production of TNF-α,IL-10 andIL-12p70 while inhibited IFN-γ secretion,increased the percentage of CD2~+ cells while decreased that of CD4~+or CD45RA~+ cells.The results indicate that the viruses isolated in Nanjing are HHV-7,which has similarbiological characteristic to the known HHV-7 strain,DC.Infection with HHV-7 in vitro could affect immunefunction of lymphocytes by disturbing cytokine production and CD antigen expression.Cellular & MolecularImmunology.2004;1(5):367-372. 相似文献
26.
本文报道了47例重症肌无力患者的神经电生理表现。重复频率刺激(RNS)异常率为53%,其中,腋神经19条,递减14条(73%);面神经23条,递减10条(43%);尺神经33条,递减12条(36%)。23例病人进行了常规肌电图检查,12例运动单位时限缩短(54%)。文中讨论了重复频率刺激,腋神经阳性率最高,而尺神经阳性率最低的原因。 相似文献
27.
本文回顾了国内护理人员信息系统研究的背景和现状,介绍了作者自行研制的护理人员信息管理系统的结构和功能,并将其用于护士继续教育和规范化培训的管理过程,已取得较好成果。护理人员信息管理系统的开发与应用旨在适应未来护理的发展需求,促进护理管理的现代化。 相似文献
28.
p16与c-myc基因表达产物在肝细胞癌及癌旁组织中的表达及临床意义 总被引:3,自引:3,他引:0
目的:探讨p16、c-myc蛋白与肝细胞癌(HCC)的发生、发展及恶性程度的关系。方法:应用免疫组织化学法检测了69例HCC和63例癌旁组织p16及c-myc蛋白的表达,并结合临床资料进行分析。结果:p16蛋白主要分布在胞浆,少数细胞核内也可见阳性显色。c-myc蛋白主要分布在胞核。p16蛋白在肝癌组织及癌旁组织中的阳性率分别为26.5%(18/69)和92%(58/63),两者比较差异显著(P〉 相似文献
29.
肝移植术后出凝血功能的调控 总被引:18,自引:1,他引:17
目的:探讨肝移植术后出凝血功能的调控方法及意义。方法:通过11 例活体肝部分移植术病例,介绍术后出凝血功能的监测指标及调控方法。结果:肝移植术后出凝血功能调控的目标为维持血压、脉搏相对稳定,控制下列指标在一定范围内。 Hb :90 ~110g/ L, Ht:25 % 上下, P L T:30 ~50 ×109/ L, P T:15 ~20s , A C T:150 ~200s,调控手段是依据上述指标补充凝血因子或使用扩血管剂或抗凝剂。结论:本研究所介绍的方法能有效防止肝移植术后的出血和血栓形成。 相似文献
30.
Increasing sampling density improves reproducibility of optical coherence tomography measurements. 总被引:1,自引:0,他引:1
R Gurses-Ozden H Ishikawa S T Hoh J M Liebmann A Mistlberger D S Greenfield H L Dou R Ritch 《Journal of glaucoma》1999,8(4):238-241
PURPOSE: Published series of peripapillary retinal nerve fiber layer (RNFL) measurements using optical coherence tomography (OCT) have sampled 100 evenly distributed points on a 360 degrees peripapillary circular scan. The goal of this study was to determine whether a four-fold increase in sampling density improves the reproducibility of OCT measurements. METHODS: Complete ophthalmic examinations, achromatic automated perimetry, and OCT imaging were performed in all patients. The OCT scanning consisted of three superior and inferior quadrantic scans (100 sampling points/quadrant) and three circular scans (25 points/quadrant). The RNFL thickness measurements and coefficient of variation (CV) were calculated for the superior and inferior quadrants for each sampling density technique. RESULTS: The study included 22 eyes of 22 patients (3 control subjects; 2 patients with ocular hypertension; and 17 patients with glaucoma). Quadrants with associated glaucomatous visual field loss on automated achromatic perimetry had thinner RNFLs than quadrants without functional defects for both the 25- and 100-points/quadrant scans. For quadrants associated with normal visual hemifields (n = 22), there was no difference between the 25- and 100-points/quadrant scans in mean RNFL thickness and CV. Among quadrants with visual field defects (n = 22), RNFL thickness measurements were thinner in the 25-points/quadrant scans than in the 100-points/quadrant scans. The CV for the 25-points/quadrant scans (25.9%) was significantly higher than that for the 100-points/quadrant scans (11.9%). CONCLUSION: Increasing the sampling density of OCT scans provides less variable representation of RNFL thickness. The optimal sampling density to achieve maximal reliability of OCT scans remains to be determined. 相似文献