维持性血液透析患者贫血治疗达标情况探究及影响因素分析

目的 选择维持性血液透析患者,对其贫血治疗达标情况进行探究,并分析其影响因素,以指导采取相应的预防措施。方法 便利选取该院2019年4月—2021年4月收治的82例维持性血液透析患者开展研究,按照血红蛋白水平将其分为两组：达标组（n=37例,血红蛋白水平≥110 g/L）、未达标组（n=45例,血红蛋白水平<110 g/L）,比较两组基线资料,同时借助多因素Logistic分析法分析其影响因素。结果 经单因素分析发现,达标组与未达标组的透析时间[（2.69±1.40）年vs (4.10±2.03)年]、血清白蛋白[（39.30±3.19）g/L vs (38.10±2.05)g/L]、C反应蛋白[（9.89±2.33）mg/L vs (12.21±3.10)mg/L]、铁缺乏（8.11%vs 26.67%）比较差异有统计学意义（P<0.05）;经多因素Logistic回归分析发现,发现透析时间（OR=1.439）、血钙低水平（OR=2.053）、C反应蛋白（OR=2.065）、铁缺乏（OR=1.371）是维持性血液透析患者发生贫血的独立危险因素（P<0.05）,而血清...     

维持性血液透析患者中代谢综合征发病情况及危险因素分析

目的了解维持性血液透析患者中代谢综合征（MS）的发生情况,并分析相关危险因素。方法收集202例接受维持性血液透析患者的临床资料。根据国际糖尿病联盟MS诊断标准,将患者分为MS组和非MS组,计算MS的发病率;比较两组患者的体格测量数据、实验室指标、透析处方及心血管事件发生情况。对与MS发生可能相关的危险因素进行多因素Logistic回归分析。结果 202例患者中MS发病率为29.2%。两组患者以下指标比较差异均有统计学意义（P〈0.05）,包括体质量、腰围、体质量指数、血清谷丙转氨酶、胆固醇、三酰甘油、低密度脂蛋白、高密度脂蛋白、空腹血糖、C反应蛋白（CRP）和全段甲状旁腺激素水平（iPTH）,尿素下降率、尿素清除指数及透析频率和每周透析时间。MS组与非MS组心血管事件发生率（25.4%vs18.2%）比较差异无统计学意义（P〉0.05）。多因素Logistic回归分析表明,体质量（优势比OR=24.625）、女性（OR=8.000）、CRP（OR=4.700）、iPTH（OR=2.525）与MS的发生相关。结论 MS在维持性血液透析患者中并不少见,女性、肥胖、高iPTH和高CRP是MS发生的危险因素。     

慢性肾衰竭维持性血液透析患者肺部感染的危险因素分析

目的 探讨慢性肾衰竭维持性血液透析患者肺部感染的危险因素。 方法 回顾性研究2011年1月-2016年12月在金华市中心医院血液净化中心维持性血液透析 ≥ 6个月的344例患者资料,其中男性179例(52.0%),女性165例(48.0%),平均年龄(56.7±16.3)岁。根据透析病程中是否有肺部感染,将其分为肺部感染组52例(15.1%)和非肺部感染组292例(84.9%)。观察2组患者人口学资料、既往病史、首次透析前肾功能指标、钙磷代谢指标、贫血指标、基础肾病构成。采用Logistic回归分析分析维持性血液透析患者肺部感染的危险因素。 结果 Logistic多因素回归分析显示,年龄 ≥ 60岁(OR=1.833,95% CI:1.216~2.521,P=0.023)、糖尿病(OR=1.542,95% CI:1.178~2.934,P=0.035)、心功能分级(OR=3.325,95% CI:2.154~5.243,P<0.001)和血红蛋白<70 g/L(OR=2.119,95% CI:1.745~3.634,P=0.014)是维持性血液透析患者肺部感染的独立危险因素。 结论 肺部感染是血液透析患者常见的并发症,年龄 ≥ 60岁、糖尿病、心功能分级和血红蛋白<70 g/L是其独立危险因素,需对其进行早期评估和干预。      

血液透析患者低血压发生的危险因素及护理对策

目的：分析血液透析患者低血压发生的危险因素,提出相应的护理对策。方法：将104例血液透析者根据是否发生低血压分为低血压组（40例）、非低血压组（64例）,对发生低血压的危险因素进行Logistic回归分析。结果：两组年龄、透析龄、左室肥厚、超滤量、超滤率、甲状旁腺素（PTH）、血红蛋白、血糖、营养不良比较差异有统计学意义（P〈0．05）;Logistic分析显示左室肥厚（OR=2．82）、高血糖（OR=2．13）、高PTH（OR=2．06）、超滤率高（OR=3．13）、营养不良（OR=2．89）是发生低血压的独立危险因素。结论：血液透析过程中低血压发生的因素复杂,血液透析前应对患者进行合理评估,制定个性化透析方案,及时调整透析参数,积极预防低血压。     

血清碱性磷酸酶水平预测维持性血液透析患者冠状动脉钙化

目的：探究维持性血液透析（maintenance hemodialysis,MHD）患者冠状动脉钙化的相关危险因素。方法：纳入2018年3月—2020年3月在南京医科大学第一附属医院血液净化中心规律血液透析,且透析龄≥3个月的 MHD患者188 例,收集患者临床资料和实验室指标,冠状动脉多层螺旋CT测定冠状动脉钙化积分（coronary artery calcification score,CACS）,分析冠状动脉钙化的相关危险因素。结果：冠状动脉钙化（CACS＞100分）的发生率为54.8%（103/188）,CACS中位数为143（0,728）分。与CACS＜100分组相比,CACS≥400分组患者年龄、透析龄、血清钙、甲状旁腺激素（intact parathyroid hormone,iPTH）、碱性磷酸酶（alkaline phosphatase,ALP）等指标显著增高（P＜0.05）。Spearman相关分析显示,CACS与年龄（r=0.292,P＜0.001）、透析龄（r=0.242,P＜0.001）、收缩压（r=0.167,P=0.024）、血钙（r=0.263,P＜0.001）、iPTH（r=0.191,P=0.009）及ALP（r=0.171,P=0.019）呈正相关（P＜0.05）;多因素线性回归显示ALP与CACS显著相关（P=0.012）。受试者工作特征曲线分析示ALP预测重度冠状动脉钙化的曲线下面积是0.615（P=0.009）,最佳临界值为226.5 U/L。多因素Logistic回归分析显示经过多因素校正后ALP≥226.5 U/L组患者重度冠脉钙化风险显著升高（OR=3.05,95%可信区间：1.30~7.18,P=0.011）。结论：血清ALP水平是MHD患者冠状动脉钙化的独立预测因子,ALP有望成为MHD患者心血管钙化的预测指标和干预靶点。     

联合透析法对维持性血液透析患者透析充分性及体质指数的影响

目的：探讨血液透析联合血液灌流的血液透析效果及影响透析充分性的因素。方法：以我院2018年1月至2020年2月开始维持性血液透析患者为研究对象，根据患者的年龄、性别及透析龄进行配对，最终联合治疗组（血液灌流+血液透析）和对照组（单纯血液透析）各47例，观察期1年；比较两组患者体重指数（BMI）、肱三头肌皮褶厚度（TSF）、血清C反应蛋白（CRP）、白细胞介素-6(IL-6)、白细胞介素-12(IL-12)等炎性因子水平、血浆白蛋白（ALB）及血钙（Ca）、磷（P）、钙磷乘积和甲状旁腺激素（PTH）水平；采用Logistic多因素回归方法分析影响透析充分性的因素。结果：联合透析方式与单纯血液透析患者治疗后IL-6、CRP、IL-12及P、钙磷乘积、PTH、ALB比较，差异均具有统计学意义（P<0.05）,Ca差异无统计学意义（P>0.05）；两组患者持续透析12个月后，BMI及TSF比较差异有统计学意义（P<0.05）；回归分析结果表明患者BMI、自费是影响透析充分性的危险因素（P<0.05），联合透析可增强透析的充分性（OR=0.199）。两组患者的感染率和不良...     

血液透析患者认知功能障碍及相关危险因素

目的 初步探讨接受长期血液透析治疗患者认知功能损害的患病率及其相关危险因素。方法 采用横断面调查方案,收集123例30岁以上因慢性肾功能不全需长期血液透析治疗的患者,采用中文版蒙特利尔认知量表进行认知功能评估,并分析与认知功能损害相关的危险因素。结果 123例患者中,84例有认知功能损害,患病率高达68. 3%。多因素Logistic回归分析发现,高龄（OR = 1.090;95% CI：1.034 - 1.147;P = 0.001）、男性（OR = 5.213;95% CI：1.758 - 15.455;P = 0.003）、受教育时间小于等于5年（OR = 0.076;95% CI：0.014 – 0.420;P = 0.003）及高血压史（OR = 6.891;95% CI：2.042 - 23.258;P = 0.002）是长期血液透析治疗患者认知功能损害的独立危险因素。结论 长期血液透析治疗的患者认知功能损害患病率高,男性、高龄、受教育时间小于等于5年和高血压是其独立危险因素。     

急性髓系白血病患者血清腺苷脱氨酶测定的意义

目的 探讨血清腺苷脱氨酶(ADA)在急性髓系白血病(AML)的变化规律及其意义.方法 收集山东省立医院2012年1月至2013年12月75例治疗前急性髓系白血病患者(其中63例AML患者进行自身治疗前后比较)和86例健康对照者外周血血清.采用PNP-XTO-POD偶联连续监测法测定血清腺苷脱氨酶(ADA)水平,采用速率法测定谷草转氨酶(AST)、谷丙转氨酶(ALT)和谷氨酰转肽酶(GGT)水平.检测健康对照组与AML组血清ADA水平,比较AML治疗前后ADA水平变化,采用受试者工作特征曲线(ROC曲线)确定ADA最佳截点,并将AML治疗前患者分为低ADA组(ADA<13.50 U/L)和高ADA组(ADA≥13.50 U/L),分析两组间年龄、性别、AST、ALT和GGT差异.结果 AML组患者ADA水平[15.30(9.50,31.30)U/L]显著高于健康对照组[8.45(7.05,11.35)U/L],差异有统计学意义(P<0.001);AML组治疗后ADA水平[10.70(8.10,14.90)U/L]显著低于AML治疗前[14.70(9.60,26.70)U/L],差异有统计学意义(P<0.001);采用ROC曲线,将AML治疗前患者分为高ADA组(ADA≥13.50 U/L)和低ADA组(ADA<13.50 U/L),其中高ADA组中AST、ALT及GGT水平显著高于低ADA组(AST Z=-3.102,P=0.002;ALT Z=-2.046,P=0.041;GGT Z=-2.794,P=0.005).结论 ADA检测可以作为AML患者的一项常规辅助检查,对AML的疾病诊断及评估病情的发展具有一定的价值.     

终末期肾病血液透析相关性腹水发生情况及其相关危险因素的探讨

目的:探讨维持性血液透析（maintenance hemodialysis, MHD）患者透析相关性腹水发生情况及相关危险因素。方法:选择于我院规律行血液透析的终末期肾脏病患者168例为研究对象,根据有无腹水情况分为腹水组(17例)和非腹水组（151例）。收集患者临床资料,比较两组患者各项临床及生化指标;对相关危险因素进行Logistic回归分析。结果:MHD患者中透析相关性腹水患病率为10.1%,两组患者临床资料比较显示血白蛋白（ALB）、细胞外液（ECV）、细胞内液（ICV）、细胞外液与细胞内液比值（E/I）、腹膜透析史、透析间期体重增加比有统计学意义（P＜0.05）;Logistic回归分析显示低白蛋白、腹膜透析史、体重增加比增高、ECV增多、E/I比值增加是维持性血液透析患者腹水发生的相关危险因素。结论:MHD患者腹水发生率较高,应针对相关危险因素采取综合有效的干预措施。     

糖尿病血液透析患者透析过程中低血糖发生情况及其影响因素研究

背景　糖尿病血液透析（HD）患者透析过程中易发生低血糖,尤其是无症状性低血糖,但目前关于糖尿病HD患者透析过程中发生低血糖影响因素的研究报道较少。目的　分析糖尿病HD患者透析过程中低血糖发生情况及其影响因素。方法　选取2017年1月-2019年12月在杭州市西溪医院血透中心行HD的糖尿病患者86例,均接受常规治疗、血糖控制治疗。监测所有患者在研究开始后1个月12次HD过程中（上机30 min内）血糖值,分析其低血糖发生情况及血糖变异性;糖尿病HD患者透析过程中发生低血糖的影响因素分析采用单因素分析和多元有序Logistic回归分析。结果　86例患者中40例未发生低血糖（未发组）,24例发生1次低血糖（偶发组）,22例发生≥2次低血糖（常发组）,低血糖发生率为53.5%（46/86）。三组患者年龄、体质指数（BMI）、子女情况、文化程度、用药依从性、照顾能力、血糖平均值（MBG）、血糖变异系数（CVBG）比较,差异有统计学意义（P<0.05）;多元有序Logistic回归分析结果显示,年龄增大〔OR=1.079,95%CI（1.000,1.160）〕、用药依从性差〔OR=13.250,95%CI（2.300,76.250）〕、照顾能力差〔OR=4.067,95%CI（1.090,15.300）〕、MBG<8.91 mmol/L〔OR=4.001,95%CI（1.250,12.850）〕是糖尿病HD患者透析过程中发生低血糖的危险因素,而BMI增大〔OR=0.776,95%CI（0.640,0.950）〕、CVBG<0.26〔OR=0.254,95%CI（0.080,0.790）〕是保护因素（P<0.05）。结论　糖尿病HD患者透析过程中低血糖发生率较高（为53.5%）,年龄增大、用药依从性差、照顾能力差、MBG<8.91 mmol/L是糖尿病HD患者透析过程中发生低血糖的危险因素,而BMI增大、CVBG<0.26是保护因素。     

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.