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971.
四物汤对红细胞免疫及骨髓干细胞增殖能力的影响   总被引:27,自引:0,他引:27  
用四物汤对辐射损伤小鼠进行治疗.结果表明:电离辐射对小鼠红细胞免疫功能及骨髓干细胞增殖能力有明显的抑制作用,应用四物汤治疗后红细胞免疫功能得到恢复,说明四物汤有较明显的增强红细胞免疫功能的作用.由骨髓干细胞增殖实验中可看出四物汤可使受照小鼠的骨髓干细胞增殖能力恢复正常.该研究为四物汤治疗辐射损伤引起的红细胞免疫功能及造血功能低下提供了实验依据.  相似文献   
972.
Gastrodia elata is an achlorophyllous and fully mycoheterotrophic orchid which obtains carbon and other nutrients from Armillaria species in its life cycle. Many researchers suggested that plant hormones, as signing molecules, play a central role in the plant–fungi interaction. In the process of Armillaria gallica 012 m cultivation, both exogenous indole-3-acetic acid (IAA) and indole-3-butyric acid (IBA) distinctly stimulated the growth of mycelia in solid media. The differential expression genes (DEGs) of A. gallica 012 m with IAA versus blank control (BK) and IBA versus BK were investigated. The results showed that more than 80% of DEGs of the IAA group were coincident with the DEGs of the IBA group, and more than half of upregulated DEGs and most of the downregulated DEGs of the IAA group coincided with those DEGs of the IBA group. Above research implied that A. gallica 012 m could perceive IAA and IBA, and possess similar responses and signaling pathways to IAA and IBA. The overlapping differential genes of the IAA group and IBA group were analyzed by GO term, and the results showed that several DEGs identified were related to biological processes including positive regulation of the biological process and biological process. The downregulated NmrA-like and FKBP_C genes might be benefit to the growth of mycelia. Those results can explain that exiguous IAA and IBA improved the growth of A. gallica to some extent. We speculate that IAA and IBA are signaling molecules, and regulate the expression of growth-related genes of A. gallica 012 m by the same signaling pathway.  相似文献   
973.
目的 比较新型国产人工颈椎间盘置换与颈椎前路减压植骨融合内固定术对山羊施术节段邻近颈椎间盘退变的影响。方法 12只实验山羊随机分为3组,每组4只:间盘组(CDR组)行C3/4间盘摘除、新型国产人工颈椎间盘植入术;融合组(ACDF组)行C3/4间盘摘除、植骨融合内固定术;对照组不进行手术。分别于术后1、3个月行颈椎正侧位X线检查,根据改良Kellgren评分法及椎间盘相对高度测量(RDH)法进行评价。结果 动物实验中所有山羊均成活,无切口感染及肢体瘫痪。间盘组与对照组在术后1个月与3个月Kellgren评分比较,差异无统计学意义(P>0.05);术后1个月与术后3个月融合组Kellgren评分高于间盘组,且差异有统计学意义(P<0.05)。三组术前的RDH比较差异无统计学意义,术后1个月及3个月融合组的RDH均低于间盘组、对照组,且与两组比较差异均有统计学意义(P<0.05),间盘组与对照组术后RDH比较差异无统计学意义(P>0.05)。结论 新型国产人工颈椎间盘置换可以有效防止山羊颈椎手术邻近节段的退变。  相似文献   
974.
He W  Hu C  Qiu W 《中华肿瘤杂志》1997,19(5):374-377
目的评价B超对肺癌急症的快速鉴别诊断价值。方法应用B超诊断肺癌急症35例,其中有中央型右上肺癌肿块压迫引起的上腔静脉综合征(SVC)5例,探查取胸骨右缘第2、3肋间;中大量心包积液伴亚急性心包填塞症10例,包括心肌与心包转移癌致急性出血性心包积液2例,探查取心前区及左腋前线第5、6肋间;恶性胸腔大量积液20例,探查位于两侧背部膈上。介入性治疗,B超定位穿刺抽液并腔内注入中药榄香烯乳,配合临床化疗药物、输血等综合治疗。结果在4周内急症得到暂时缓解者占82.8%,稳定占8.5%,无效占8.5%。结论简便、可重复性的超声诊断及时、可靠,并可提供疗效参考依据,证实榄香烯乳对控制急性心肌心包出血有特效,起乳剂微栓止血作用。对部分包裹性胸腔积液无效。B超对SVC诊断有一定局限性。  相似文献   
975.
He X  Li M 《中华眼科杂志》1997,33(6):406-409,I026
目的 了解培养的小梁细胞分泌表皮生长因子(epidermal growth factor,EGF)及细胞膜上表皮生长因子受体(epidermal growth factor receptor,EGFR)的情况。方法 进行人眼小梁细胞体外培养。用EGF cDAN探针,α^-32p同位素标记及斑点杂交放射自显影法,检测小梁细胞分泌EGFmRNA的情况。结果 人眼小梁细胞体外培养成功。免疫组化染色显示小  相似文献   
976.
The REGD procedure of the S.A.G.E. [1994] system was used to determine the mode of inheritance of the rare disease given in Problem 1. The likelihood ratio test statistic indicated that we should reject the hypotheses of dominant and recessive inheritance at the 0.01 level, so codominant inheritance was assumed. The estimated penetrance values computed from the β estimates given by the S.A.G.E. output were 1.0, 0.7, and 0.0 for the AA, AB, and BB genotypes respectively. A sample of three markers from each chromosome was used to determine which chromosome(s) gave evidence of having loci linked to the disease locus. The lod minus 0.83 support interval, which has been shown to provide the best approximation to 95% coverage among interval estimates [Nemesure et al., in press], was obtained for each of these markers. The criterion for rejecting the hypothesis of close linkage using the support interval methodology required that the left side of the lod minus 0.83 support interval about the maximum likelihood estimate, $ {\rm \hat \theta } $, includes only values greater than θ = 0.10. This criterion suggested that chromosomes 2, 3, and 6 did not contain the disease genes. Classical lod-score linkage analysis using the usual criteria of 3.0 for linkage and -2.0 for exclusion did not result in any regions being identified. On dropping the required lod score to 1.0, chromosomes 1, 3, and 6 gave results in favor of linkage with lod scores of 1.94 (θ = 0.19), 1.20 (θ = 0.24), and 1.30 (θ = 0.23), respectively. Association studies comparing unrelated cases to unrelated controls were done for all markers on all chromosomes. Two associations were observed which were significant at the 0.05 level after adjusting for the large number of multiple comparisons being made. The strongest association observed was between allele 7 of marker 23 on chromosome 5 and the disease (χ = 52.20, or = 4.7) and the second strongest was between allele 8 of marker 31 on chromosome 1 (χ = 20.10, OR = 3.4). ©1995 Wiley-Liss, Inc.  相似文献   
977.
Osteopontin is an acidic phosphoprotein containing casein kinase II (CKII) phosphorylatable sites and an acidic amino acid cluster. The metabolically 32P-labelings of both serines and threonines in vitro in osteopontin immunoprecipitated from rat osteoblast-like ROS 17/2.8 cells may suggest that casein kinase II catalyzes this modification. The enzyme occurs in microsomal fractions of rat osteoblast-like ROS 17/2.8 cells. Subcellular fractions containing endoplasmic reticulum and Golgi apparatus were isolated by differential centrifugation and were identified according to their ultrastructures and the presence of marker enzymes such as glucose-6-phosphatase and thiamine pyrophosphatase, respectively. Both fractions phosphorylated the partially dephosphorylated osteopontin and the specific substrate peptide RRREEETEEE. Endoplasmic reticulum-catalyzed peptide phosphorylation was 2.7 times lower than that of Golgi although both endoplasmic reticulum- and Golgi-catalyzed peptide reactions were 50% inhibited by 20 and 100 ng/ml heparin, respectively. Western blot analysis revealed that both fractions contained osteopontin and microsomal CKII. Furthermore, microsomal CKII was immunogold-labeled in endoplasmic reticulum and Golgi apparatus. Heparin inhibition and utilization of [-32P]GTP as a phosphate donor by both fractions confirmed their capacity to phosphorylate osteopontin. The results suggest that microsomal CKII modifies the acidie matrix proteins during transportation. These matrix phosphoproteins may participate in the mineralization process of hard tissues.  相似文献   
978.
Objective: The objective of this study was to determine whether human papillomavirus (HPV) infections are involved in the development of papillomatosis lesions of the lower female genital tract.Methods: A total of 616 biopsy specimens of genital papillomatous lesions (307 nodular and 309 papular types) from 598 patients were anaylyzed for the presence of HPV DNA sequences by polymerase chain reaction (PCR). These specimens were also examined by histopathological assessment for characteristic HPV-associated cytological changes, by immunohistochemical staining for HPV-associated antigen, and by electron microscopy for the presence of virions.Results: HPV DNA sequences were found in 97.9% (140 of 143 cases) and 1.1% (1 of 91 cases) of the nodular and papular papillomatosis cases tested, respectively. In 18 patients who had both types of papillomatosis lesions, HPV DNA was invariably found only in nodular tissues. HPV-associated antigen, koilocytosis, and virions were found in 53.6% (98 of 183 cases), 70.5% (129 of 183 cases), and 5.9% (5 of 85 cases) of nodular papillomatosis lesions tested, respectively.Conclusions: These data suggest that nodular papillomatosis was closely associated with HPV infection, but that papular papillomatosis of the lower female genital tract may have an etiology other than HPV infection.  相似文献   
979.
目的 了解中国社区老年人脑认知相关生活方式的分布特征,并探讨其综合评分对早期认知功能下降的影响。方法 研究对象来自老年期重点疾病预防和干预项目。纳入2015年基线调查及2017年随访调查均完成认知功能状况评定,且基线未患痴呆的2 537名≥60岁的社区老年人。通过问卷调查收集其脑认知相关生活方式信息(体育锻炼、社会交往、脑力休闲活动、睡眠质量、吸烟状况与饮酒状况)并计算综合评分。通过多因素logistic回归模型分析脑认知相关生活方式综合评分与早期认知功能下降的关联。结果 2 537名社区老年人群中,评分5~6分者占28.7%,6项脑认知相关生活方式因子均健康者仅占4.8%。男性与女性的健康生活方式因子分布存在差异。多因素logistic回归模型结果显示,与评分0~3分组相比,评分4分和5~6分组早期认知功能下降的风险降低(OR=0.683,95%CI:0.457~1.019;OR=0.623,95%CI:0.398~0.976;趋势P=0.030)。在女性中,与评分0~3分组相比,评分4分和5~6分组的早期认知功能下降的风险降低(OR=0.491,95%CI:0.297~0.812;OR=0.556,95%CI:0.332~0.929;趋势P=0.024)。结论 脑认知相关综合健康生活方式与早期认知功能下降风险降低密切相关,在女性群体中尤为显著。  相似文献   
980.
目的 调查中国人民解放军总医院研究生对临床流行病学课程的认知和学习习惯情况,评价其学习效果并分析其可能的影响因素,为改进教学方式、提高学习效果提供相关数据。方法 采用横断面研究设计方法,以中国人民解放军总医院2020级全体研究生为研究对象,采用自填问卷方式收集调查资料。分析不同类别研究生对课程认知情况、学习习惯的差异,探讨影响学习效果的相关因素。连续变量组间差异比较采用t检验或Mann-WhitneyU检验,分类变量组间差异比较采用卡方检验或McNemar检验。结果 共纳入652名研究生进行分析,硕士研究生409人(62.7%),博士研究生243人(37.3%)。博士研究生听说过临床流行病学(χ2=19.99,P<0.001)、之前学过临床流行病学(χ2=9.20,P=0.002)、对本课程感兴趣(χ2=11.41,P=0.001)、认为本课程重要(χ2=10.71,P=0.001)、课前预习(χ2=11.21,P=0.001)、课后复习(χ2=3.29,P=0.001)及课堂积极讨论(χ2=11.64,P=0.001)的比例高于硕士研究生,差异有统计学意义。授课前全体研究生测验题总分平均为(5.50±1.62),授课后总分平均为(7.47±1.90),差异有统计学意义(t=-23.49,P<0.001)。统招研究生授课后成绩提高程度高于在职研究生,硕士群体中差异有统计学意义(t=4.41,P<0.001),博士群体中差异无统计学意义(t=0.94,P=0.351)。结论 不同类别研究生对临床流行病学知识点掌握程度在授课后均得到提升。但仍需针对不同类别研究生学习基础及短板的差异,改进相应的教学模式及过程,包括采用不同的教学方式和规范学习习惯等,从而提升研究生的课程学习效果。  相似文献   
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