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991.
子宫阔韧带内静脉的解剖学研究及其临床意义 总被引:2,自引:0,他引:2
子宫底和体上部的静脉汇集于子宫角处浅出,应称子宫上静脉。该静脉续为卵巢静脉。子宫上静脉1条者占30%,2条者占56.7%,3条者占13.3%。子宫上静脉与输卵管峡部中点相对处的口径是3.7±0.2mm,卵巢丛与子宫上静脉汇合后的口径为5.0±0.4mm。输卵管峡部中点与子宫上静脉的间距为6.3±0.6mm。在输卵管系膜中见有输卵管静脉汇入子宫上静脉。本文研究结果认为盆腔静脉淤血症的发生,与结扎手术中损伤子宫上静脉和输卵管静脉有关。 相似文献
992.
应用粗糙集理论对心电图波形所蕴涵的大量信息进行处理,目的是评价心电信号实测指标与冠心病的关系。通过对心电图导联I中采集的心电信号进行属性约简,降低决策表的冗余性,提取用于判别冠心病的重要属性和诊断规则。实例分析表明,粗糙集理论应用于心电信号分析,可得到清晰简明的诊断规则,有助于冠心病的临床诊断。 相似文献
993.
研究了纳米硒和亚硒酸钠对断奶仔猪肝脏谷胱甘肽过氧化物酶和脱碘酶活性的影响。将纳米硒和亚硒酸钠2种硒源分别以0.1、0.2、0.3、0.4、0.5、1.0 mg/kg 6个硒水平添加到基础日粮中,配制成12种试验日粮,基础日粮作对照,饲养“杜长大”断奶仔猪(8.3 kg左右)。结果表明:以亚硒酸钠形式添加的硒浓度为1.0 mg/kg时,仔猪生长性能和GSH-Px活性显著低于0.2~0.4 mg/kg硒添加水平(P<0.05),纳米硒添加浓度为1.0 mg/kg,仔猪生长性能和GSH-Px活性仍然保持在高峰平台;硒源添加浓度为0.10~0.40 mg/kg时,两种硒源对GSH-Px活性的影响无显著差异(P>0.05);在0.50和1.0 mg/kg硒添加水平上,纳米硒组GSH-Px活性显著高于亚硒酸钠组(P<0.05)。基础日粮组肝脏脱碘酶活性显著低于各硒源的添加水平(P<0.05),硒源和硒添加水平对脱碘酶活性没有显著影响(P>0.05)。上述结果提示:纳米硒的Weinberg剂量-效应的最适剂量范围宽于亚硒酸钠。 相似文献
994.
995.
高血压病患者血清IGFⅡ的变化 总被引:3,自引:7,他引:3
目的 :探讨胰岛素样生长因子Ⅱ (IGFⅡ )与高血压病 (EH)以及与高血压伴左室肥厚 (EH伴LVH)的关系。方法 :采用放射免疫分析 10 0例未治疗的EH患者和 5 0例正常人血清IGFⅡ水平。并用彩色多普勒诊断仪测定 10 0例EH患者的左心室重量 (LVM )。结果 :EH患者血清IGFⅡ水平明显高于正常人[(0 6 6± 0 35 )ng/ml:(0 4 4± 0 14 )ng/ml,p <0 0 1],EH伴LVH者IGFⅡ高于EH非LVH者 [(0 82± 0 4 0 )ng/ml:(0 5 4± 0 2 0 )ng/ml,p <0 0 1]。结论 :EH患者IGFⅡ水平升高 ,其升高程度与病情密切相关 ,IGFⅡ可能参与了EH心肌肥厚的形成 相似文献
996.
Equine infectious anemia virus (EIAV) is a lentivirus that causes persistent infections in horses. We hypothesized that high-avidity CTL specific for nonvariable epitopes might be associated with low viral load and minimal disease in EIAV-infected horses. To test this hypothesis, memory CTL (CTLm) responses were analyzed in two infected horses with high plasma viral loads and recurrent disease (progressors), and in two infected horses with low-to-undetectable viral loads and mild disease (nonprogressors). High-avidity CTLm in one progressor recognized an envelope gp90 epitope, and the data documented for the first time in EIAV that viral variation led to CTL escape. Each of the nonprogressors had high-to-moderate avidity CTLm directed against epitopes within Rev, including the nuclear export and nuclear localization domains. These results suggested that the epitope specificity of high- and moderate-avidity CTLm was an important determinant for disease outcome in the EIAV-infected horses examined. 相似文献
997.
医学图像序列压缩是远程医疗系统中的重要技术,而运动估计在视频序列压缩中起着关键作用。我们提出了一种改进的正方形-菱形搜索算法来实现医学图像序列的运动估计。这种改进的正方形-菱形算法减少了搜索点数。我们将其应用于小波域的医学图像序列的运动估计,并对数字减影血管造影图像序列(DSA)进行实验。结果表明,改进后的小波域正方形-菱形算法较其他算法精度高。 相似文献
998.
Detection of cytomegalovirus infection during a vaccine clinical trial in healthy young women: seroconversion and viral shedding. 总被引:3,自引:0,他引:3
Changpin Zhang Hannah Buchanan William Andrews Ashley Evans Robert F Pass 《Journal of clinical virology》2006,35(3):338-342
BACKGROUND: An antibody method based on absorption of serum with cytomegalovirus (CMV) glycoprotein B (gB) was developed for detection of infection during clinical trials of CMV gB vaccine. Previous study showed that this method detected the antibody response to infection and was negative with vaccine induced immunity. OBJECTIVES: In an ongoing efficacy trial of CMV gB vaccine the ability of the gB-absorbed CMV IgG assay to detect CMV infection was assessed and compared with viral culture results. STUDY DESIGN: Two hundred and ninety two healthy, seronegative young women in a phase II, double-blind, placebo-controlled, clinical trial of recombinant CMV gB vaccine (sanofi pasteur) with MF59 adjuvant (Chiron) were randomized to receive CMV gB vaccine or placebo (1:1) on a 0, 1 and 6 month schedule. Participants were screened every 3 months for CMV infection using the gB-absorbed CMV IgG assay, and a subgroup was also screened for infection with viral cultures. Viral culture (urine, vaginal swab and saliva) was used to confirm CMV infection in all subjects with a positive gB-absorbed CMV IgG result. RESULTS: Evidence of CMV infection (gB-absorbed CMV IgG levels>or=5.0 AU/ml) was found in 23/292 (7.88%) study participants. The gB-absorbed CMV IgG levels of their first positive serum ranged from 15.7 to 251.0 AU/ml with a mean of 77.0 AU/ml and a median of 44.9 AU/ml. Cytomegalovirus was isolated from all 23 of them from culture specimens collected after their first positive gB-absorbed CMV IgG. The time to first CMV positive culture from first positive gB-absorbed CMV IgG ranged from 0 to 12 weeks with a median of 2 weeks. CONCLUSIONS: The gB-absorbed CMV IgG assay detects CMV infection in CMV gB vaccine clinical trials earlier and more rapidly than virus culture and does not reveal whether subjects received CMV gB vaccine or placebo. 相似文献
999.
背景:随着疾病治疗模式的改变,人们已经意识到中医药在激素性股骨头坏死治疗过程中的重要性,因此利用生物信息学从分子水平分析激素性股骨头坏死的发病机制,构建疾病风险模型,并预测具有潜在治疗作用的中药,为后期中医药治疗激素性股骨头坏死提供一定的理论依据。目的:基于生物信息学挖掘激素性股骨头坏死的竞争性内源RNA(ceRNA)调控网络,分析其在激素性股骨头坏死中的分子调控机制,预测相关疾病靶点并构建疾病风险模型,同时预测具有潜在治疗作用的中药。方法:检索GEO数据库,下载激素性股骨头坏死的矩阵文件GSE123568和基因注释文件GPL15207。借助R语言等软件分析得到差异表达的长链非编码RNA与mRNA,并通过公共数据库预测与差异表达长链非编码RNA关联的miRNA-mRNA,再将预测到的mRNA与差异表达mRNA取交集,整合得到ceRNA网络。随后采用STRING数据库和Cytoscape软件筛选关键基因,利用R语言分析关键基因的功能与相关通路,并挖掘关键ceRNA网络。最后根据关键基因构建激素性股骨头坏死的风险模型,并进行中药预测。结果与结论:(1)与健康对照相比,激素性股骨头坏死患者共有7个长链非编码RNA和1763个mRNAs存在差异表达;(2)筛选出STAT3、KAT2B、AGO4、JAK2、JAK1、PTGS2共6个关键基因;(3)关键基因所富集的功能包括对肽激素的反应、白细胞介素6介导的信号通路、细胞对白细胞介素6的反应等生物学过程,涉及JAK-STAT、脂肪细胞因子、催乳素等信号通路;(4)4种mi RNAs(mi R-135a-5p、mi R-137、mi R-17-5p、miR-20b-5p)和2种长链非编码RNA(SNHG11、C20orf197)可能在导致激素性股骨头坏死发生发展过程中发挥关键作用;(5)KAT2B最有可能是激素性股骨头坏死发生发展的风险因子;(6)郁金、淫羊藿、黄芪具备治疗激素性股骨头坏死疾病靶点的可能。通过对激素性股骨头坏死相关长链非编码RNA介导的ceRNA网络进行分析,识别出潜在的疾病靶点、信号通路及潜在治疗中药,为进一步阐明其发病机制,并为后续的实验研究提供参考依据。 相似文献
1000.
Xiang F Buervenich S Nicolao P Bailey ME Zhang Z Anvret M 《Journal of medical genetics》2000,37(4):250-255
Rett syndrome (RTT) was first described in 1966. Its biological and genetic foundations were not clear until recently when Amir et al reported that mutations in the MECP2 gene were detected in around 50% of RTT patients. In this study, we have screened the MECP2 gene for mutations in our RTT material, including nine familial cases (19 Rett girls) and 59 sporadic cases. A total of 27 sporadic RTT patients were found to have mutations in the MECP2 gene, but no mutations were identified in our RTT families. In order to address the possibility of further X chromosomal or autosomal genetic factors in RTT, we evaluated six candidate genes for RTT selected on clinical, pathological, and genetic grounds: UBE1 (human ubiquitin activating enzyme E1, located in chromosome Xp11.23), UBE2I (ubiquitin conjugating enzyme E2I, homologous to yeast UBC9, chromosome 16p13.3), GdX (ubiquitin-like protein, chromosome Xq28), SOX3 (SRY related HMG box gene 3, chromosome Xq26-q27), GABRA3 (gamma-aminobutyric acid type A receptor alpha3 subunit, chromosome Xq28), and CDR2 (cerebellar degeneration related autoantigen 2, chromosome 16p12-p13.1). No mutations were detected in the coding regions of these six genes in 10 affected subjects and, therefore, alterations in the amino acid sequences of the encoded proteins can be excluded as having a causative role in RTT. Furthermore, gene expression of MECP2, GdX, GABRA3, and L1CAM (L1 cell adhesion molecule) was also investigated by in situ hybridisation. No gross differences were observed in neurones of several brain regions between normal controls and Rett patients. 相似文献