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91.
目的:筛选中药三棱抗血栓活性部位并对其化学成分进行研究。方法:采用斑马鱼血栓模型对中药三棱80%乙醇提取物的石油醚部位、乙酸乙酯部位、正丁醇部位和水部位的抗血栓作用进行测试。以硅胶柱色谱等方法对抗血栓作用显著的部位进行分离纯化,通过NMR,MS等方法并结合文献数据鉴定化合物结构。结果:乙酸乙酯萃取物能显著增加斑马鱼血栓模型的心脏染色强度(P<0.01),其余各部位抗血栓作用不明显。在该部位分离得到11个化合物,分别鉴定为对羟基苯甲酸(1)、5-羟甲基糠醛(2)、对甲氧基苯甲醛(3)、对羟基苯甲醛(4)、对香豆酸(5)、阿魏酸(6)、香草酸(7)、原儿茶酸(8)、香兰素(9)、Methyl-3,6-dihydroxy-2-[2-(2-hydroxyphenyl)-ethynyl]benzoate (10)及1,3-O-二阿魏酰基甘油(11)。结论:三棱提取物的乙酸乙酯萃取部位具有显著的抗血栓作用,其主要化学成分为酚酸类化合物。 相似文献
92.
目的探讨不良孕产史夫妇染色体异常核型检出率及其分布,以及染色体异常核型与不良孕产史的关系,为优生优育及遗传咨询提供理论依据。 方法选取2016年1月1日至2017年12月31日,于济南艾迪康医学检验中心进行染色体核型检测的10 330对(20 660例)不良孕产史育龄夫妇为研究对象。采集每例受试者肘静脉血3 mL,肝素钠抗凝,取0.3 mL进行血细胞培养、标本制备,采用常规G显带技术进行染色体核型分析。对于染色体异常核型检出率、不同类型染色体异常核型占染色体异常核型总例数的比例等计数资料,采用率(%)表示。本研究遵循的程序符合2013年修订的《世界医学协会赫尔辛基宣言》要求。 结果①本组10 330对(20 660例)不良孕产史育龄夫妇中,共计检出染色体异常核型为1 119例(不含染色体多态性),染色体异常核型检出率为5.42%(1 119/20 660)。其中,常染色体异常者为658例,占染色体异常核型的58.80%(658/1 119),包括354例染色体平衡易位、205例染色体倒位、83例染色体罗伯逊易位、11例染色体插入、5例染色体重复,分别占染色体异常核型的31.64%、18.32%、7.41%、0.98%、0.45%。染色体倒位者中,以9号染色体倒位居多,偶见于1、4、7、11、12号染色体,并且多合并自然流产。性染色体异常者为440例,占染色体异常核型的39.32%(440/1 119),包括365例性染色体数目异常(占染色体异常核型的32.62%)。其中,男性多表现为无精子症,以47,XXY染色体异常核型居多(144例),女性多表现为原发性不孕,以45,X染色体异常核型居多(103例); 61例为性染色体结构异常、14例为性别反转,分别占染色体异常核型的5.45%、1.25%。其他罕见染色体异常核型者为21例,占染色体异常核型的1.88%(21/1 119),如环状染色体、mar染色体等。②本组10 330对(20 660例)不良孕产史育龄夫妇中,11例为常染色体插入,5例为常染色体重复,54例为性染色体缺失,其主要临床表现为原发性不孕不育、胚胎停止发育、无精子症或重度少精子症。 结论染色体异常核型是导致育龄期夫妇不良孕产史的重要原因之一。对于不良孕产史夫妇,建议进行染色体核型分析和遗传咨询。临床为这类患者进行优生优育指导,可提高出生人口质量。 相似文献
93.
In this paper, a novel impulsive control law is proposed for synchronization of stochastic discrete complex networks with time delays and switching topologies, where average dwell time and average impulsive interval are taken into account. The side effect of time delays is estimated by Lyapunov–Razumikhin technique, which quantitatively gives the upper bound to increase the rate of Lyapunov function. By considering the compensation of decreasing interval, a better impulsive control law is recast in terms of average dwell time and average impulsive interval. Detailed results from a numerical illustrative example are presented and discussed. Finally, some relevant conclusions are drawn. 相似文献
94.
Melamine is a raw material in the chemical industry. Because of its high nitrogen content, melamine has been utilized by unscrupulous businessmen as a food additive to enhance the indices of protein content in food and feed testing. Tetrahymena has long been used as an excellent model organism in toxicological studies. The purpose of the present study was to determine the effect of melamine on Tetrahymena. In the present study, the effects of melamine on the proliferation and mating rate of Tetrahymena were examined by microscopic counting of the cell numbers. The comet assay and DAPI nuclear staining were performed to analyze the changes in the Tetrahymena genome. Flow cytometric analysis was conducted to detect apoptosis. Furthermore, RT-PCR was performed to determine the changes in the expression of the metallothionein gene in Tetrahymena that underwent stress treatment with varying concentrations of melamine. The results indicated that melamine affected the proliferation and sexual reproduction of Tetrahymena. High melamine concentrations damaged the Tetrahymena genome to a certain extent and induced apoptosis in the organism. Expression of the metallothionein gene was upregulated in Tetrahymena exposed to melamine stress to ameliorate melamine-induced damage. These results indicated that melamine displayed significant toxicity to Tetrahymena cells. 相似文献
95.
96.
复发性口腔溃疡是口腔科常见多发性疾病,与多种因素导致的自体免疫失衡有关。表现为免疫细胞活性和数量上的改变,特别是高表达或不正常表达CD4+、 CD8+细胞以及 CD4+/ CD8+的改变,并伴有多种细胞因子的变化,包括 IL-2 、IL-6、IL-8﹑IL-10、INF-γ 和TNF-α等多种细胞因子的异常表达以及相关细胞因子的基因突变导致的基因多态性。T淋巴细胞介导的细胞免疫在复发性口腔溃疡疾病的发生、发展过程中起重要作用。 相似文献
97.
《Health & place》2020
UK and international studies point to significant area variation in diabetes risk, and summary indices of diabetic risk are potentially of value in effective targeting of health interventions and healthcare resources. This paper aims to develop a summary measure of the diabetic risk environment which can act as an index for targeting health care resources. The diabetes risk index is for 6791 English small areas (which provide entire coverage of England) and has advantages in incorporating evidence from both diabetes outcomes and area risk factors, and in including spatial correlation in its construction. The analysis underlying the risk index shows that area socio-economic status, social fragmentation and south Asian ethnic concentration are all positive risk factors for diabetes risk. However, urban-rural and regional differences in risk intersect with these socio-demographic influences. 相似文献
98.
《Annals of anatomy》2014,196(6):464-470
IntroductionQuadriceps heads are important in biomechanical stabilization and in the pathogenesis osteoarthritis of the knee. This is the first study to explore the relative distribution of quadriceps head anatomical cross-sectional areas (ACSA) and volumes, and their response to pain and to training intervention.MethodsThe relative proportions of quadriceps heads were determined in 48 Osteoarthritis Initiative participants with unilateral pain (65% women; age 45–78 years). Quadriceps head volumes were also measured in 35 untrained women (45–55 years) before and after 12-week training intervention. Cross-sectional areas of the vastus medialis (VM), inter-medius (VIM), and lateralis (VL), and of the rectus femoris (RF) were determined from axial T1-weighted MR images.ResultsThe proportion of the VM on the total quadriceps ACSA increased from proximal to distal. The difference in quadriceps ACSA of painful (vs. pain-free) limbs was −5.4% for the VM (p < 0.001), −6.8% for the VL (p < 0.01), −2.8% for the VIM (p = 0.06), and +3.4% for the RF (p = 0.67) but the VM/VL ratio was not significantly altered. The muscle volume increase during training intervention was +4.2% (p < 0.05) for VM, +1.3% for VL, +2.0% for VIM (p < 0.05) and +1.6% for RF.ConclusionThe proportion of quadriceps head relative to total muscle ACSA and volume depends on the anatomical level studied. The results suggest that there may be a differential response of the quadriceps heads to pain-induced atrophy and to training-related hypertrophy. Studies in larger samples are needed to ascertain whether the observed differences in response to pain and training are statistically and clinically significant. 相似文献
99.
100.
ZHANG Ji ZHOU Hai Jian XU Li HU Guang Chun ZHANG Xue Hua XU Sheng Ping LIU Zun Yu SHAO Zhu Jun 《Biomedical and environmental sciences : BES》2013,26(5):331-337
Objective To characterize the meningococcal strains isolated from cases and close contacts with meningococcal disease associated with an outbreak in a jail in May 2010 by investigating the national distribution of hyperinvasive ST-4821 serogroup C clone associated with this outbreak. Methods The cases were described based on the clinical symptoms and laboratory results. Pharyngeal swabs were cultured for N. meningitidis from men in the jail. Meningococcal isolates were identified by serogrouping, pulsed-field gel electrophoresis (PFGE) and multilocus sequence typing (MLST), respectively. Four hundred and sixteen serogroup C N. meningitidis strains were collected from 27 provinces between 2003 and 2010 for a nationwide survey and analyzed by PFGE and MLST. Results Three persons in a jail system were infected with invasive N. meningitidis serogroup C. All isolates tested had matching PFGE patterns and belonged to the multilocus sequence type (ST) 4821 clonal complex. All 47 N. meningitidis strains were identified from the pharyngeal swabs of 166 peoples in the jail, and 26 of them belonged to ST-4821 serogroup C clone, and 90.14% (375/416) serogroup C strains identified in the nationwide survey belonged to the ST-4821 complex. The ST-4821 serogroup C clone was spread nationwide, distributed in 24 provinces, especially in eastern provinces between 2003 and 2010. Conclusion Endemic transmission and carriage rate of ST-4821 serogroup C clone are high in this jail system. The ST-4821 serogroup C clone is spreading in China and nationwide distributed despite the existence of some effective vaccines. 相似文献