基于对侧眼眼轴计算硅油眼人工晶体度数的准确性

目的：探讨使用对侧眼眼轴计算硅油眼患者人工晶体度数的准确性。方法：将拟行硅油取出联合白内障超声乳化吸除及人工晶体植入术的患者60例（60眼）随机分为A、B、C组。A组20例,硅油填充眼直接使用光学相干生物测量仪IOL-Master计算人工晶体度数;B组20例,使用IOL-Master测量对侧眼眼轴长度和硅油眼角膜曲率,计算人工晶体度数;C组20例,使用患眼硅油填充前IOL-Master测量的眼轴长度和硅油眼角膜曲率,计算人工晶体度数。三组均使用SRK/T公式计算人工晶体度数并植入相应度数晶体。术后1个月测量实际屈光度,并与预期屈光度比较,计算绝对屈光误差（MAE）,观察使用三种方法计算人工晶体度数的准确性。结果：角膜曲率：纳入研究患者硅油填充前、硅油填充后角膜曲率分别为（43.29±0.85）D、（43.52±1.05）D,差异无统计学意义（t=1.690,P>0.05）;A、B、C三组硅油填充眼角膜曲率分别为（43.26±0.57）D、（43.53±1.04）D、（43.78±1.39）D,差异无统计学意义（F=1.238,P>0.05）。眼轴长度：纳入患者硅油填充前、硅...     

A超测量硅油填充眼眼轴及人工晶状体度数的临床评价

目的评价A超经修正后测量硅油填充眼眼轴及人工晶状体（IOL）度数的准确性。方法应用我院现有的法国QUANTELMEDICAL公司的CompattachIIA／B超声仪采用实验的方法对超声波在纯Ox5700型硅油、患者眼中取出的硅油及平衡盐溶液中的传播速度进行测量及比较,进而对眼轴值进行修正,最终推算出准确的人工晶状体度数。选取25例行玻璃体切割伴硅油填充术的患者,应用公认0x5700型硅油的测量值对患眼进行眼轴的测量,再用我们实验所得到的测量值分别对患眼进行坐位及平卧位的眼轴测量,最后将坐位时测出的跟轴长度代入SRKⅡ公式计算拟植入的人工晶状体度数。行硅油取出术联合白内障摘除＋人工晶状体植入术。术后3个月测量患眼的眼轴、最佳矫正视力及屈光状态。对手术前后眼轴长度及最佳矫正视力进行对比,将术后屈光状态与术前预期值比较。结果纯Ox5700型硅油的比色杯宽度为（31．440±0．011）mm,患眼中取出硅油的比色杯宽度为（31．420±0．047）mm,两者间差异无统计学意义（P〉0．05）。平衡盐溶液的比色杯宽度为21．07mm。取油前,硅油填充眼的玻璃体腔的传播速度设置为990m／s时的患眼平均眼轴长度为（23．219±0．125）mm。传播速度设置为1027in／s时坐位测量患眼平均眼轴长度为（24．103±0．135）mm,平卧位患眼平均眼轴长度为（24．116±0．128）mm。取油后患眼平均眼轴长度为（24．018±0．135）mm。硅油的传播速度设置为1027m／s时坐、卧位测量的眼轴值同取油后患眼的眼轴值差异无统计学意义（P〉0．05）。传播速度设置为990m／s时的测量值与取油后眼轴长度及传播速度设置为1027m／s时测量的眼轴长度差异有统计学意义（P〈0．05）。手术后屈光度与术前预期值差值平均为（-1．50±2．00）D,差异无统计学意义（P〉0．05）。结论A超经修正后可准确测量硅油填充眼的眼轴长度,进而准确推算出硅油填充眼的IOL度数,A超测量硅油填充眼眼轴及IOL度数是相对准确、安全、方便的方式,但各医院应对自身的仪器及材料进行实验测量,进而得出更加适合本院的实验数值。     

浸润式B超眼轴测量在高度近视性白内障手术中的应用

目的 探讨浸润式B超眼轴测量在高度近视性白内障手术中的应用。方法 选取2021年6月-12月于新疆自治区人民医院白内障手术者68例（103眼），根据眼轴长度分为2组：高度近视组（75眼），眼轴≥26.5mm；对照组（28眼），眼轴22mm-24mm。利用IOL-Master、A超和浸润式B超分别测量眼轴，术中利用IOL-Master数据计算结果植入人工晶状体（IOL）度数，利用A超和浸润式B超眼轴结果在网络平台上利用Barrett universalⅡ公式计算IOL度数。术后1个月随访，计算平均屈光度绝对误差（MAE）。结果 对照组中，IOL Master、A超及浸润式B超测量AL长度依次为22.91±0.62mm、22.83±1.21 mm和22.93±2.07 mm，三者间差异无统计学意义（F=0.038,P=0.962）。三种方法术后MAE依次为0.24±0.54 D、0.44±0.61 D和0.40±0.72 D，三者间差异无统计学意义（F=0.796,P=0.455）。高度近视组中，IOL Master、A超及浸润式B超测量AL长度依次为28.91±2.79mm、28.58±...     

IOL-Master测量硅油眼眼轴长的精确度评价

  目的 评价IOL-Master测量硅油填充眼眼轴长的精确度。方法 采用IOL-Master测定玻璃体切割联合眼内硅油填充术3-~6个月后行硅油取出术的30例眼的眼轴长度。其中18例在硅油取出同时植入人工晶体（IOL）,植入前后分别测量眼轴长。结果 硅油取出术前后的眼轴平均长度分别为（24.27±3.01 01）mm和（24.26±2.79 79）mm,两组间差异无统计学意义。IOL-Master和A超两种方法测量硅油眼的眼轴长度无显著差异超2种方法测量硅油眼的眼轴长度无显著差异。结论 IOL-Master测量硅油眼眼轴长的精确度高,可用于硅油取出联合IOL植入的IOL度数计算。     

白内障合并高度近视人工晶状体计算公式的选择

目的 以临床资料验证SRK T公式和SRK Ⅱ公式的准确性.方法 收集43例(43眼)高度近视(眼轴长度≥26.0 mm)白内障接受超声乳化联合人工晶状体植入术患者的临床资料.43眼按眼轴长度分为两组:A组(25眼)眼轴长度＜29.0 mm,B组(18眼)眼轴长度≥29.0 mm.分组比较采用SRK T和SRK Ⅱ公式分别计算的平均绝对预测屈光误差值及应植入人工晶状体度数间的相差幅度及分布.结果 分别以SRK T和 SRK Ⅱ公式计算预测眼屈光度数,平均绝对预测屈光误差值在A组分别为(1.33±0.67)D和(1.40±0.59)D,差异无统计学意义(P＞0.05);在B组分别为 (0.84±0.65)D和(1.42±0.87)D,差异有统计学意义(P＜0.05).A组采用SRK T和 SRK Ⅱ公式分别计算的应植入人工晶状体度数相差≤±0.5 D者为84%;B组经SRK T和 SRK Ⅱ公式分别计算的应植入人工晶状体度数相差≥±2.0 D者为61.11%.结论 对于眼轴长度≥29.0 mm的高度近视白内障眼,SRK T公式更适用,其结果 的准确性优于SRK Ⅱ公式.     

白内障合并高度近视人工晶状体计算公式的选择

目的以临床资料验证SRK-T公式和SRK-Ⅱ公式的准确性。方法收集43例(43眼)高度近视(眼轴长度≥26.0 mm)白内障接受超声乳化联合人工晶状体植入术患者的临床资料。43眼按眼轴长度分为两组:A组(25眼)眼轴长度<29.0 mm,B组(18眼)眼轴长度≥29.0 mm。分组比较采用SRK-T和SRK-Ⅱ公式分别计算的平均绝对预测屈光误差值及应植入人工晶状体度数间的相差幅度及分布。结果分别以SRK-T和SRK-Ⅱ公式计算预测眼屈光度数,平均绝对预测屈光误差值在A组分别为(1.33±0.67)D和(1.40±0.59)D,差异无统计学意义(P>0.05);在B组分别为(0.84±0.65)D和(1.42±0.87)D,差异有统计学意义(P<0.05)。A组采用SRK-T和SRK-Ⅱ公式分别计算的应植入人工晶状体度数相差≤±0.5 D者为84%;B组经SRK-T和SRK-Ⅱ公式分别计算的应植入人工晶状体度数相差≥±2.0 D者为61.11%。结论对于眼轴长度≥29.0 mm的高度近视白内障眼,SRK-T公式更适用,其结果的准确性优于SRK-Ⅱ公式。     

IOL-Master和A超测量人工晶体度数的两种方法比较

目的比较IOL-Master与A超对人工晶体度数测量的准确性.方法 109例115眼年龄相关性白内障患者,术前分别采用IOL-Master、A超和自动验光仪测量眼部参数,使用SRK-T公式计算植入人工晶体的度数,并将所有眼分为短眼轴组（L≤22 mm）,正常眼轴组（22 mm〈L≤26 mm）和长眼轴组（L〉26 mm）,术后1月检查患者屈光状态并作分析.结果用A超和IOL-Master检测眼轴长度：L≤22 mm组分别为（21.40±0.34）mm和（21.48±0.26）mm,22 mm〈L≤26 mm组分别为（23.65±0.85）mm和（23.67±0.80）mm,L〉26 mm组分别为（29.16±1.83）mm和（29.25±1.91）mm,所有组别两者对比差异无统计学意义（P〉0.05）;术后1个月,A超与IOL-Master测得的术后平均绝对屈光误差值（MAE）比较：L≤22 mm组分别为（0.70±0.49）D和（0.44±0.26）D,22 mm〈L≤26 mm组分别为（0.53±0.46）D和（0.47±0.41）D,L〉26 mm组分别为（0.81±0.49）D和（0.71±0.29）D,所有组别两者对比差异无统计学意义（P〉0.05）;不同眼轴组中,两种方法测得的MAE≤0.50 D及MAE≤1.00 D患者的百分率对比差异无统计学意义（P〉0.05）.结论 IOL-Master与A超在人工晶体测量上具有高度的一致性,是一种高准确性、非接触性、操作简单、安全可靠的人工晶体度数测量工具.     

非接触性光学相关生物测量仪与传统超声在测量高度近视眼人工晶体度数中的比较

目的 比较非接触性光学相关生物测量仪(IOL-Master)与传统超声(A/B超)在测量高度近视眼人工晶体度数的准确性,了解IOL-Master的特性及其临床应用价值.方法 112例112只高度近视眼并发白内障患者随机分为两组,术前分别用IOL-Master、A/B超测量仪及角膜曲率计测量眼轴长度和角膜曲率,使用SRK-Ⅱ或SRK/T公式计算人工晶体度数.对患者施行超声乳化白内障吸出术,术中分别按上述两种测量方法测得结果并植入可折叠人工晶体.术后3个月随诊检查视力及眼屈光度并作分析.结果 IOL-Master和A/B超测量法,测得的眼轴长度两者对比差异无显著性(P>0.05);IOL-Master和角膜曲率计测量角膜曲率分别为(44.32±1.56)D、(43.97 4±1.39)D,两者对比差异无显著性(P>0.05);按两种测量方法随机分组的两组病人,术后3个月的平均绝对屈光误差两组对比差异无显著性(P>0.05).结论 IOL-Master是一种高精确性、非接触性、操作简单、安全可靠的人工晶体度数测量工具.     

超声乳化联合负度数人工晶状体植入治疗白内障合并超高度近视

目的观察超声乳化白内障吸除联合负度数人工晶状体植入术治疗白内障合并超高度近视的临床疗效。方法对15例（26眼）白内障合并超高度近视眼患者,施行超声乳化白内障吸除联合负度数人工晶状体植入术,记录术前矫正视力、眼轴长度、屈光度数及其与预期屈光度数的偏差值,观察手术并发症和术后眼部情况。结果术前眼轴长度30.12～35.76mm,平均为32.45mm。术中均顺利植入人工晶状体,无后囊破裂发生。植入屈光度数为-1.0～-6.0D,术后1周,24眼视力均有不同程度的提高,最佳矫正视力≥0.2共20眼（76.9%）,其中≥0.5者共8眼（30.77%）。2眼因严重的黄斑区网膜萎缩变性,视力无明显提高。术后屈光度数偏差值〈±2.00D共22眼（84.6%）,〈±1.00D共14眼（53.8%）。随访时间为3～24个月。后囊膜皱褶6眼,后发性白内障7眼,5眼行激光后囊膜切开术,无视网膜和脉络膜脱离发生,无眼压升高。4例单眼白内障患者中,1例出现双眼干扰症状。结论超声乳化白内障吸除联合负度数人工晶状体植入既可以进行屈光矫正,又可以增加眼内组织的稳定性,减少视网膜脱离的发生,是治疗白内障合并超高度近视眼安全、有效的方法。     

白内障手术患者IOL-Master和A超眼内生物学测量比较

目的比较IOL-Master仪与A型超声(A超)在测量白内障手术患者中央前房深度、眼轴长度及人工晶体上的差异。方法选取接受白内障手术的患者120例138眼,术前分别采用IOL-Master仪和A超完成中央前房深度以及眼轴的测量,比较测量结果的差异。将患眼平均分为IOL-Master组和A超组,应用SRK-T公式计算人工晶体度数;超声乳化联合折叠式人工晶体植入术后随访3个月以上,行屈光检查比较两组在人工晶体测量结果上的准确性。结果术前采用IOL-Master与A超测量得到的平均中央前房深度和平均眼轴长度差异无统计学意义(P>0.05);但在高度近视眼中两种测量结果的差异有统计学意义(P<0.05)。随访期末,术眼平均等效球镜度数与预期值差异≤0.50 D和≤1.00 D者,两组差异均无统计学意义(P>0.05);但在高度近视眼中差异有统计学意义(P<0.05)。结论IOL-Master仪与A超测量的术前前房深度和眼轴的结果一致,但在高度近视眼中IOL-Master的准确性较好。     

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.