基于网络药理学探索蒙药肉豆蔻治疗缺血性心脏病的作用机制

目的 采用网络药理学探索蒙药肉豆蔻治疗缺血性心脏病的作用机制。方法 通过中药系统药理学分析平台（TCMSP）,检索得到蒙药肉豆蔻的主要化学成分以及作用靶点。使用Uniprot数据库,检索与靶蛋白相对应的基因,运用软件（Cyoscape 3.7.2）绘制“化合物-靶点-通路”网络模型进行可视化,通过DAVID数据库进行GO分析以及KEGG通路分析,预测其作用机制。结果“化合物-靶点-通路”网络模型中包含10个化合物以及与之对应的靶点54个,关键性靶点涉及PTGS2、KDR、MMP9、ESR1、JAK2等。肉豆蔻治疗缺血性心脏病涉及催乳素信号通路、雌激素信号通路、炎症信号通路、癌症通路等多条信号通路。结论 本文将网络药理学运用于蒙药肉豆蔻治疗缺血性心脏病中,筛选活性成分、靶点蛋白、相关信号通路,将三者结合绘制“活性成分-靶蛋白-通路”网络图并预测其作用机制,为后期研究蒙药肉豆蔻治疗缺血性心脏病提供新的研究思路。     

基于网络药理学和分子对接的三九胃泰颗粒抗炎镇痛作用机制研究

目的:基于网络药理学探讨三九胃泰颗粒抗炎镇痛的潜在作用机制。方法:通过TCMSP数据库和相关文献筛选出三九胃泰颗粒的活性成分，并对其活性成分作用靶点进行预测，运用Cytoscape软件构建“三九胃泰颗粒-潜在活性成分-靶点”网络。通过GeneCards数据库收集炎症、疼痛相关靶点并与药物靶点相交集。通过STRING数据库对交集靶点进行蛋白质-蛋白质相互作用(PPI)分析，京都基因与基因组百科全书(KEGG)通路富集、基因本体(GO)分析于DAVID数据库中进行。Cytoscape软件构建“三九胃泰颗粒潜在活性成分-炎症疼痛相关靶点-通路”网络。AutoDockTools和PyMOL软件用于三九胃泰颗粒抗炎镇痛核心成分和核心靶点的分子对接。结果:共获取三九胃泰颗粒的潜在活性成分73种，其中核心活性成分15个，包括槲皮素、山柰酚、β-谷甾醇等；三九胃泰颗粒发挥抗炎镇痛作用的核心靶点22个，包括PTGS2、HSP90AB1、PTGS1等，参与药物的应答、炎症应答、MAPK级联的正调节等生物过程，涉及脂质和动脉粥样硬化、TNF、PI3K-AKT、MAPK等信号通路。核心成分槲皮素、山柰酚、β-...     

蒙药复方协日嘎-4的网络药理学研究

目的对蒙药复方协日嘎-4进行网络药理学研究,探索其治疗前列腺增生、前列腺癌等疾病的活性成分和作用靶点,运用计算机网络药理学技术对协日嘎-4所含化学成分的作用机制进行分析。方法通过中国知网,万方数据库等数据库筛选蒙药复方协日嘎-4所含化合物信息,通过Pubmed、Super Target、Drug Bank、TTD(Therapeutic Targets Database)等数据库收集蒙药协日嘎-4中化学成分对应的靶点,通过KEGG(Kyoto Encyclopedia of Genes and Genomes)、IPA(Ingenuity Pathway Analysis)等数据库收集相关信号通路,采用Cytoscape软件建立多成分-多靶点和多成分-多靶点-多疾病网络模型。结果药物与靶点之间存在的相关性为潜在靶点的探索提供了一条新途径。筛选结果显示蒙药复方协日嘎-4中有33种化合物与12种生物靶标存在网络交互作用,他们之间的相关性,揭示了网络药理学"多成分""多靶点"的特征。同时化合物与靶点连接最终共同作用于疾病即良性前列腺增生和前列腺癌,建立了蒙药复方协日嘎-4化学成分-靶点-疾病网络模型。通过数据库筛选得到两条主要信号通路,雄激素受体(AR)信号通路和Wnt/β-连环蛋白(Wnt/β-catenin)信号通路。结论本文建立了一条"疾病-靶点-药物"的蒙药复方网络药理学的研究模式,为蒙药的研究和发展提供了新的思路和方法。     

GC-MS、UPLC-Q-TOF-MS/MS结合网络药理学探讨地锦草药效物质基础及其抗炎作用机制

目的 采用色谱联用技术分析地锦草主要成分,并联合网络药理学预测其抗炎作用的潜在靶点和信号通路,阐明地锦草治疗炎症的作用机制。方法 通过GC-MS、UPLC-Q-TOF-MS/MS技术分析地锦草的化学成分,借助中药系统药理数据库和分析平台（Traditional Chinese Medicine Systems Pharmacology, TCMSP）、地锦草相关文献筛选地锦草活性成分;采用SwissTargetPrediction数据库预测靶点,采用GeneCards、DrugBank、DisGeNET数据库获取地锦草相关治疗靶点,将成分靶点和疾病靶点取交集,获得交集靶点;凭借STRING 11.5数据库和Cytoscape 3.9.0软件构建蛋白质-蛋白质相互作用（protein-protein interaction, PPI）网络,并筛选核心靶点。采用DAVID 6.8进行GO注释和KEGG通路富集分析,构建“化合物-靶点-通路”网络。结果 GC-MS、UPLC-QTOF-MS/MS分别鉴定出50、76种成分,筛选出地锦草抗炎的12个活性成分及214个成分靶点;根据数据库筛选得到...     

基于网络药理学和分子对接技术研究八珍益智方治疗阿尔茨海默病的潜在作用机制

目的 利用网络药理学方法及分子对接技术,研究八珍益智方治疗阿尔茨海默病（Alzheimer's disease,AD）的潜在药效物质基础和作用机制,为其临床应用提供理论依据。方法 通过TCMSP、BATMAN-TCM、TCMID、中国知网（CNKI）和Pubmed数据库检索八珍益智方8味组方药材化学成分和作用靶点;通过GeneCards、OMIM数据库查询AD的相关靶点;利用R语言3.6.3得到药物和疾病的交集靶点;借助String数据库和Cytoscape 3.7.2软件构建PPI网络,筛选核心靶点;通过DAVID数据库进行GO功能富集分析和KEGG通路富集分析;利用AutoDock tools 1.5.6、AutoDock vina 1.1.2进行分子对接。结果 八珍益智方共收集到200个化学成分和226个靶点,Cytoscape 3.7.2软件筛选出包括AKT1、MAPK3、IL-6、VEGFA、CASP3等37个核心靶点,槲皮素、山柰酚、柚皮苷、豆甾醇、7-甲氧基-2-甲基异黄酮等15个核心化合物。GO富集分析得到1 331个条目（P<0.05）,KEGG通路富集得到相关通路65条（P<0.05）。分子对接结果显示15个核心化合物和AKT1、MAPK3、IL-6、VEGFA、CASP3具有较好的亲和力。结论 八珍益智方治疗AD的通路主要涉及癌症的途径、MAPK信号通路、前列腺癌、神经活性配体-受体相互作用、钙信号通路等,研究结果为八珍益智方治疗AD作用机制的进一步阐明提供了指引。      

基于网络药理学探讨桑枝降压的作用机制

目的:采用网络药理学探讨桑枝治疗高血压的作用机制.方法:通过TCMSP、Batman-TCM、化学专业数据库和CNKI收集桑枝的化学成分,并通过Swiss Target Prediction数据库收集成分相关靶点;通过GeneCards、OMIM等数据库得到与高血压有关的疾病靶点.取成分靶点与疾病靶点的交集,得到交集靶点;利用String数据库和Cytoscape3.7.1软件,筛选并构建交集靶点相互作用网络;并利用String数据库对交集靶点进行PPI分析、GO分析和KEGG通路分析,并通过Cytoscape软件对结果进行可视化;最后对活性成分与关键靶点进行分子对接验证.结果:通过筛选得到桑枝活性成分18个,潜在作用靶点336个,其中与高血压有关的交集靶点87个;共获得545条GO分析条目和160条KEGG信号通路,分别主要涉及血压调节、调节血管大小等生物过程以及cGMP-PKG信号通路、Rap1信号通路、PI3K/Akt信号通路 、Ras信号通路等信号通路;分子对接结果显示18个活性成分与14个关键靶点相结合,其中16个活性成分与其相应关键靶点具有较好结合活性.结论:桑枝可能通过作用于与舒张血管、细胞凋亡等相关的靶点和通路,发挥治疗高血压的作用.     

基于网络药理学的鸡血藤抗肝纤维化机制研究

目的运用网络药理学探讨鸡血藤抗肝纤维化的分子生物学机制。方法利用中药系统药理学数据库与分析平台检索鸡血藤的所有化学成分,并筛选鸡血藤中的活性成分。对筛选出的活性成分进行靶点预测、基因注释。采用GeneCards、OMIM数据库筛选肝纤维化相关的疾病靶点,通过取活性成分靶点和疾病靶点的交集获得鸡血藤抗肝纤维化的潜在靶点。针对鸡血藤抗肝纤维化潜在靶点,利用STRING数据库构建蛋白互作网络图,并进行基因本体论(GO)功能富集分析和京都基因与基因组百科全书(KEGG)通路分析。结果最终筛选出鸡血藤的活性成分24个及其对应靶点56个,肝纤维化的疾病靶点共6 899个。取交集后,获得鸡血藤抗肝纤维化的潜在靶点49个,其中度值排前5位的靶点依次为表皮生长因子受体、MYC、白细胞介素6、雌激素受体1和血管内皮生长因子。GO功能富集分析和KEGG通路分析结果显示,鸡血藤抗肝纤维化的潜在靶点参与了154个生物学过程、23个细胞成分和46个分子功能,涉及前列腺癌信号通路、人类巨细胞病毒感染信号通路、乙型肝炎信号通路、卡波西肉瘤相关疱疹病毒感染信号通路、磷脂酰肌醇-3-激酶/蛋白激酶B信号通路、EB病毒感染...     

基于网络药理学方法探讨败毒散治疗COVID-19的潜在性

目的 基于网络药理学方法筛选出败毒散的潜在成分、作用靶点及其信号通路,探讨败毒散治疗新型冠状病毒肺炎(COVID-19)的潜在性。方法 利用中药系统药理学数据库与分析平台(TCMSP)对败毒散的药材进行逐一的检索,筛选出潜在活性成分及其对应靶点,应用Cytoscape3.7.2软件对成分和靶点进行网络构建与分析。在GeneCards、TTD等数据库中筛选COVID-19的相关靶点。将通过药物筛选得到的靶点与通过疾病筛选得到的靶点进行交集,在DAVID数据库中进行基因注释的GO分析和信号通路的KEGG富集分析。结果 利用数据库的检索和分析,筛选得到败毒散潜在成分107个,对应靶点189个。GeneCards、TTD数据库中筛选到与COVID-19有关靶点736个,二者取交集得到靶点42个。GO分析条目161条,KEGG信号通路54条。结论 败毒散可能通过多成分、多靶点、多通路,对发挥抗COVID-19具有一定的潜在作用,潜在活性成分对ACE2具有一定的作用。     

基于网络药理学探讨加味参附颗粒治疗慢性心力衰竭的潜在靶点及作用机制

【目的】利用网络药理学预测加味参附颗粒治疗慢性心力衰竭（CHF）的潜在靶点及其作用机制。【方法】通过TCMSP和BATMAN数据库获取加味参附颗粒的相关活性成分和靶点，通过GeneCards、DisGeNET数据库遴选慢性心力衰竭相关的靶点，取交集靶点；运用STRING数据库进行靶蛋白互作分析。运用Metascape数据库对药物-疾病共同靶点进行基因本体论（GO）和京都基因与基因百科全书（KEGG）富集分析。运用Cytoscape 3.9.1软件构建成分-靶点-通路网络图。【结果】筛选出加味参附颗粒中42个活性成分和435个直接作用的蛋白靶点，得到38个药物-疾病交集靶点。GO与KEGG富集分析结果显示，加味参附颗粒在血液循环、清除氧自由基、平滑肌细胞的调节、细胞和基因调控等多生物过程方面，通过IL-6、RELA、TNF、VEGFA、MMP-2、MAPK8、TP53、EDN1、MMP-9等核心靶点，流体剪切应力与动脉粥样硬化途径、AGERAGE、HIF-1、MAPK、IL-17、TNF、cAMP、钙等信号通路治疗慢性心力衰竭。【结论】加味参附颗粒可通过改善心脏供血、抑制炎症反应、抗氧化...     

基于网络药理学探讨贝母瓜蒌散干预哮喘气道黏液高分泌及气道重塑的作用机制

目的 基于网络药理学探讨贝母瓜蒌散治疗哮喘气道黏液高分泌及气道重塑的潜在作用机制。方法 检索中药系统药理学数据库与分析平台（TCMSP）和2020年版《中华人民共和国药典》中贝母瓜蒌散组方药物化学成分,筛选其活性成分和靶点,并使用UniProt数据库进行靶点名称校正。检索GeneCards、OMIM数据库获得哮喘、气道重塑和气道黏液高分泌靶点。将药物靶点和疾病靶点取交集,采用STRING 11.5数据库构建蛋白质-蛋白质相互作用网络,并用DAVID 6.8数据库对交集靶点进行GO功能及KEGG通路富集分析。结果 共获得贝母瓜蒌散的32个活性成分;得到贝母瓜蒌散治疗哮喘气道黏液高分泌及气道重塑的交集靶点45个,其中核心靶点有AKT1、TP53、JUN、TNF、IL6、RELA、EGFR、CASP3、MAPK1。GO功能富集分析获得条目422条,KEGG通路富集得到105条信号通路,涉及癌症通路、PI3K-Akt信号通路、HTLV-Ⅰ感染、乙型肝炎、TNF信号通路、HIF-1信号通路等。结论 贝母瓜蒌散可能通过多成分、多靶点、多通路协同作用治疗哮喘气道黏液高分泌及气道重塑,为以后机制研究提...     

Value of D-Dimers in patients with acute aortic dissection

Objective: To evaluatel the value of D-dimers in patients with acute aortic dissection (AAD). Methods: This study consisted of 16 patients with AAD and 27 non-AAD patients. Serum D-dimets were measured by Sta-Liatest D-DI immunoturbidimetric assay. Results: D-dimer level was higher (P ＜ 0.001) in patients with AAD(7.91 ± 5.52 μg/ml) than that in non- AAD group(1.57±1.24 μg/ml). D-dimer was positive (＞0.4 μg/ml) in all patients with AAD and in 10 control group patients (37%). Among patients with acute AAD, D-dimers tended to be higher in Stanford A than in Stanford B (8.67 ± 4.31 μg/ml vs. 3.24±1.27 μg/ml, P ＜0.01). D-dimer values tended to be higher in more extended disease(3.84 ± 1.65 μg/ml, 8.57 ± 3.58 μg/ml and 11.87 ± 5.69 μg/ml in thoracic aorta, thoracic and abdominal aorta, thoracic and abdominal aorta and iliacal arteries, respectively, P ＜ 0.05 for both 8.57 ± 3.58 and 11.87 ± 5.69 vs. 3.84 ± 1.65 ). Including the control group into the analysis, we found a sensitivity of 100%, a negative predictive value of 100%, and a specificity of 66% and a positive predictive value of 64% for D-dimer in diagnosis of AAD in our patients with suspected AAD. Conclusion: D-dimer was elevated in patients with AAD. A negative D-dimer test result could be useful in excluding AAD.     

Research of combined liver-kidney transplantation model in rats

Objective： To set up a simple and reliable rat model of combined liver-kidney transplantation. Methods： SD rats served as both donors and recipients. 4℃ sodium lactate Ringer＇s was infused from portal veins to donated livers,and from abdominal aorta to donated kidneys, respectively. Anastomosis of the portal vein and the inferior vena cava （IVC） inferior to the right kidney between the graft and the recipient was performed by a double cuff method, then the superior hepatic vena cava with suture. A patch of donated renal artery was anastomosed to the recipient abdominal aorta. The urethra and bile duct were reconstructed with a simple inside bracket. Results： Among 65 cases of combined liver-kidney transplantation, the success rate in the late 40 cases was 77.5%. The function of the grafted liver and kidney remained normal. Conclusion： This rat model of combined liver-kidney transplantation can be established in common laboratory conditions with high success rate and meet the needs of renal transplantation experiment.     

BLOOD PRESSURE CHANGE WITH AGE IN SALT-SENSITIVE TEENAGERS

Objective To observe blood pressure change with age in salt-sensitive teenagers whose salt sensitivity were determined by repeated testing.Methods Salt sensitivity was determined through intravenous infusion of normal saline combined with volume-depletion by oral diuretic furosemide in 55 teenagers. After five years, salt sensitivity was re-examined and subject blood pressure was followed up. Blood pressure changes in salt-sensitive teenagers were compared to that of non-salt sensitive teenagers over five years.Results After 5 years, the repetition rate of salt sensitivity determined by intravenous saline loading is 92.7%. In teenagers with salt sensitivity on the baseline, both the systolic blood pressure increments and increment rates were much higher than non-salt sensitive teenagers (12.7±12.1 mmHg vs. 2.8±5.2 mmHg, P＜ 0.01; 12.2%± 12.0% vs. 2.5% ±4.4%, P＜ 0.001,respectively). There was a similar trend for diastolic blood pressure (8.4 ± 6.4 mmHg vs. 3.7 ± 6.4 mmHg, P = 0.052; 13.2% ±10.6 % vs. 6.8%± 10.1%, P = 0.053, respectively).Conclusions Salt sensitivity determined by intravenous saline loading showed good reproducibility. Blood pressure increments with age were much higher in salt-sensitive teenagers than non-salt sensitive teenagers, especially in terms of systolic blood pressure.     

安心颗粒对急诊经皮冠状动脉介入术后生活质量影响的研究

目的：评价使用安心颗粒对急诊经皮冠状动脉介入术（PPCI）术后生活质量的影响.方法：将160例接受PPCI的急性ST段抬高型心肌梗死患者随机分为安心颗粒组（术前顿服安心颗粒8.8g,术后安心颗粒4.4 g/次,每日2次）和对照组（仅接受基础药物治疗）.所有患者均服用阿司匹林、氯吡格雷和阿托伐他汀.分别在入院时、出院前1d、出院后180 d时,应用心肌梗死多维度量表（MIDAS）、中文版SF-36评价量表对患者生活质量评分.并观察术后30 d以内的出血并发症、血小板减少症发生情况.结果：入院时和出院前1d,两组患者的心肌梗死MIDAS、SF-36量表评分比较无差异（P＞0.05）;出院后180 d时,与对照组比较,安心颗粒组MIDAS、SF-36评分明显减低（P＜0.05）;组内与入院时比较,两组出院前1d、出院后180 d时,MIDAS、SF-36评分均降低（P＜0.05）.两组患者在随访期间均无大量出血、少量出血、重度和极重度血小板减少症发生,安心颗粒组有4例、对照组有7例发生不明显出血（P＞0.05）.两组发生轻度血小板减少症的患者数比较无差异（P＞0.05）.结论：PPCI使用安心颗粒,能改善急性ST段抬高型心肌梗死患者的生活质量,且不增加出血风险.     

The comparative studies of the influences of Urapidil and Nicardipine on sino-atrial node function, atrio-ventricular node function and hemodynamics

Objective:To investigate the influences of urapidil and nicardipine on rabbit sinus function,atrio-ventricular node function and hemodynamics.Methods:Thirty-two Angora's rabbits were selected and randomly divided into four groups.U1 group:urapidil 0.25 mg/kg;U2 group:urapidil 0.5 mg/kg;N1 group:nicardipine 10 μg/kg;N2 group:nicardipine 20 μg/kg.All these medicine were administrated within 30 seconds.Measurements were taken before and after the administration of urapidil or nicardipine for the following data:mean blood pressure(MAP),heart rate(HR),sino-atrial conduction time(SACT),maximal sinoatrial recovery time(SNRTmax)corrected sinus node recovery time(CSNRT),index of sinus node recovery time(SNRTI),Wenckebach A-V conduction frequency (WB),and P-R interval.Results:Significant MAP and HR changes were identified in all of the four groups before and after administration of both urapidil and nicardipine.No significant changes could be found in the rest of the parameters.Intergroup analysis showed that SACT and CSNRT of N1 and N2 groups were shorter than those of the U2 group(P＜0.01);the MAP decreased(P＜0.01)and the HR increased drastically(P＜0.01).Conclusions:Neither urapidil(0.25 mg/kg,0.5 mg/kg)nor nicardipine(10μg/kg,20μg/kg)has any significant influence on rabbit sinus function or rabbit atrio-ventricular node function.Nicardipine could be a better choice than urapidil for parafunctional sinus node patients.     

Expression of OPGmRNA and ODFmRNA in the patients of hip fracture due to osteoporosis

Objective：To investigate the gene expression of osteoprotegerin（OPG） and osteoclast differentiation factor（ODF） in the bone tissue of patients with hip fracture due to osteoporosis. Methods：OPGmRNA and ODFmRNA in the bone tissue in 50 cases of osteoporosis sufferers（over 50 years old） with hip fracture（Observer Group） and 30 cases of hip facture sufferers with no osteoporosis（Control group） were analyzed with the Semi-Quantitative RT-PCR method. Results：The mRNA expressed of ODF, OPG were both high in the patients with hip fracture. In the control group, the expression of OPG mRNA was observed, while the expression of ODF mRNA was very slight. Conclusion：Aged patients contained all signals including OPG, ODF that are essential for inducing osteoclastogenesis and promoting bone resorption.     

The clinicopathological and immuohistochemical analysis of solid-pseudopapillary tumor of the pancreas： report of 9 cases

Objective：To investigate the clinical features, pathological characteristics and immunophenotype of solid-pseudopapillary tumor of the pancreas（SPTP）. Methods：Nine surgically treated cases of SPTP were retrospectively reviewed. Hematoxylin and Eosin（HE） staining and immunohistochemical staining were used to analyze all cases, and the general clinical data was collected. Results：Six patients were asymptomatic except for a palpable mass. Two patients complained of vague-epigastric pain. One patient appeared jaundice. The tumor was encapsulated and solid tissues alternately with cystic tissues. Histologically, the histological structure of solid portion was pseudopapillary with a fibrovascular core. Tumor cells were uniform and medium-sized which were arranged in sheets ets or nests or pseudopapillary patterns. Immunohistochemical studies demonstrated that SPTP proved positive in vimentin（9/9 cases）, AAT（9/9 cases）, NSE（9/9 cases）, ACT（7/9 cases）, CK20（2/9 cases）, CgA（1/9 cases）, S-100（3/gcases）, PR（4/gcases）, Syn（3/9 cases） and CD56（5/9cases）, negative in CEA and ER. Conclusion：SPTP is a tumor predominantly occurring in young women frequently without special symptoms. This tumor has various characteristical histological patterns with different immunophenotype.     

Dynamic Changes in Serum Estradiol and Progesterone levels in Patients of Premenstrual Syndrome with Adverse Flow of Liver-qi

Objective:To probe into the influence of changes of ovarian hormones on the pathogenesis of the specific sub-type premenstrual syndrome(PMS)and reveal partial microcosmic mechanisms of adverse flow of liver-qi.Methods:Estradiol(E2)and progesterone(P)levels in serum were determined at different phases of menstrual cycle by radioimmunoassay.Results:In the group of PMS with adverse flow of liver-qi.the secretive peak value Of E2 and P at the follicular phase significantly decreased,and the secretive peak value at the luteal phase did not come into being.Conclusions:Low E2 and P secretive peak at the follicular phase and absence of secretive peak at the luteal phase is one of the microcosmic mechanisms of PMS with adverse flow of liver-qi.One of the pathophysiologic mechanisms of specific sub-type PMS is probably the continuous low level of E2and P.     

Real-time Three-dimensional Echocardiography in Assessment of Left Ventricular and Right Ventricular Volumes

Real-time three-dimensional echocardiography (RT3DE)is a new ultrasound technique that enables dynamic threedimensional visualization and quantification of the heart in real time. Investigation of feasibility and methodology of RT3DE in determining left ventricular (LV) and right ventricular (RV) volumes, RT3DE was performed in 35 normal adults using Philips SONOS 7500 system with a 2-4 MHz matrix array transducer. The 60°×60° "pyramid" volume database was obtained and analyzed on a TomTec echo workstation. Both LV and RV volumes were calculated with four 3DE methods (i.e. apical 2, 4, 8, and 16-plane) through manually tracing ventricular endocardial borders in end diastole and end systole. Stroke volumes were then calculated. LV volume was also measured by 2DE Simpson's rule using GE VIVID 7 ultrasound machine.     

SCREENING FOR A 21-CHROMOSOME ABNORMALITY IN PREIMPLANTED EMBRYOS OF ELDERLY WOMEN

Increasing maternal age is the only etiological factor unequivocally linked to Down's syndrome in humans. The occurrence rate of newborns with Down's syndrome is about 1/220 in women over 35 years old. However, the occurrence rate in embryos fertilized in vitro, of the elder woman is unclear. Using FISH we screened the number of chromosome 21 in preimplanted embryos of 5 elderly women (average age, 38.4 years) to study the feasibility and necessity of screening trisomy 21 in embryos in patients over 35 years old at the in vitro fertilization (IVF) center.