呼吸道流感嗜血杆菌的分离培养与耐药性分析

目的:调查嗜血杆菌的检出率和耐药性,为临床治疗提供依据。方法:采用嗜血杆菌专用巧克力平板培养,用法国梅里埃公司提供的API-NH条鉴定和ATB-HAEMO做药敏试验。结果:副流感嗜血杆菌的检出率为12%～14%,流感嗜血杆菌的检出率为2%～3%,两者对阿莫西林-克拉维酸、头孢克洛、头孢噻肟、头孢呋辛、利福平均具有很好的敏感性。结论:呼吸道流感嗜血杆菌的检出率低,而副流感嗜血杆菌的检出率较高,治疗这类菌的感染可首选阿莫西林-克拉维酸、头孢克洛、头孢噻肟、头孢呋辛、利福平。临床微生物室应加强对呼吸道患者标本常规分离培养及药敏试验,指导临床医生合理使用抗生素,降低嗜血杆菌的耐药率。     

2004—2009年濮阳市儿童肺炎链球菌、流感嗜血杆菌耐药性调查

目的调查濮阳市近6年从儿科临床标本中分离的肺炎链球菌、流感嗜血杆菌的耐药性状况及本地流感嗜血杆菌流行的生物型。方法用API—NH和Vitek2compact对菌株进行鉴定。依据API—NH条中的鸟氨酸脱羧酶、脲酶及吲哚试验将流感嗜血杆菌分为不同的生物型。用微量肉汤稀释法分别测定其最低抑菌浓度。结果青霉素敏感肺炎链球菌（PSSP）与青霉素不敏感肺炎链球菌（PNSP）分别占48．9％、51．1％。肺炎链球菌对阿莫西林、阿莫西林／克拉维酸、头孢曲松、头孢呋辛、左氧氟沙星、万古霉素、克林霉素、红霉素的敏感率分别为75．0％、92．0％、93．6％、84．0％、100．0％、100．0％、34．1％、8．5％。40．5％的流感嗜血杆菌产β-内酰胺酶。流感嗜血杆菌生物分型以Ⅰ型、Ⅱ型、Ⅲ型为主,占85．9％。流感嗜血杆菌对氨苄西林、阿莫西林／克拉维酸、头孢曲松、头孢呋辛、左氧氟沙星、阿齐霉素的敏感率分别为73．0％、100．0％、100．0％、96．3％、100．0％、93．3％。结论本地区儿童肺炎链球菌耐药形势严峻。阿莫西林／克拉维酸、头孢曲松、头孢呋辛是治疗儿童肺炎链球菌、流感嗜血杆菌是最有活性的抗菌药物,此外,阿齐霉素对感嗜血杆菌也有很高的敏感性。     

2000-2005年自北京儿童医院门诊患儿鼻咽部分离的19群肺炎链球菌的耐药性变化

目的明确2000—2005年分离的北京儿童19群肺炎链球菌的抗生素敏感性分布及年代变化特点。方法采用简易棋盘式肺炎链球菌分型系统以荚膜肿胀试验进行血清分型。E—test法检测分离株对青霉素等6种抗生素的最低抑菌浓度（minimum inhibitory concentrations,MIC）。结果2002—2003年和2004—2005年肺炎链球菌19群在分离的青霉素不敏感肺炎链球菌中所占比例明显升高,青霉素、头孢克洛和头孢呋辛钠敏感率明显下降,MIC50、MIC90和最大MIC值的水平升高。从MIC值分布看,19群分离株对阿莫西林／克拉维酸和头孢曲松的敏感性下降,但仍处于判定标准的敏感范围。结论2000—2005年自北京儿童医院门诊患儿鼻咽部分离的肺炎链球菌19群对β内酰胺类抗生素耐药性增强,耐药株增多。     

Ⅱb群黄杆菌的耐药特征与机制的研究及对策

目的:研究Ⅱb群黄杆菌的耐药特征,探讨其耐药机制,以便采取相应对策以防止其耐药性的蔓延。方法:采用WHO提供的临床实验室标准化委员会(NCCL S)推荐的纸片琼脂扩散法,测定了2年中初次分离的87株Ⅱb群黄杆菌对环丙沙星、阿米卡星、氨苄青霉素等20种抗生素的耐药特征,并对4例Ⅱb群黄杆菌菌血症的治疗进行了分析。结果:Ⅱb群黄杆菌对环丙沙星、阿米卡星、氧氟沙星的敏感率最高,分别为79.8％、90.5％、43.3％,而对氨苄青霉素、氯霉素、头孢噻肟、阿莫西林、头孢哌酮、头孢曲松、亚胺培南、替卡西林、多西环素、氨曲南、头孢呋辛钠、替卡西林/克拉维酸、阿莫西林/克拉维酸、头孢美唑、庆大霉素高水平耐药,敏感率为0～6％,从阿米卡星、环丙沙星、氧氟沙星对Ⅱb群黄杆菌抑菌环直径分布累积百分率图看出:阿米卡星、环丙沙星为活性最好的抗生素。结论:阿米卡星、环丙沙星对所分析的Ⅱb群黄杆菌有较高的活性,是Ⅱb群黄杆菌菌血症严重感染治疗的最有效的抗生素。     

儿童肺炎链球菌对β-内酰胺类、大环内酯类和氟喹诺酮类抗菌药物敏感性研究

目的了解2002 2004年北京儿童医院门诊5岁以下呼吸道感染儿童鼻咽拭子中分离出的肺炎链球菌,对β-内酰胺类、大环内酯类和氟喹诺酮类抗菌药物的耐药性。方法使用E试验法(E-test)对114株肺炎链球菌进行抗菌药物的敏感性试验。结果114株肺炎链球菌对青霉素不敏感率为36%,对阿莫西林/棒酸全部敏感,对头孢菌素中头孢曲松不敏感率为6.1%,头孢呋辛为30.7%,头孢克洛为29%,大环内酯类耐药率在90%左右,全部菌株对氟喹诺酮类敏感。结论儿童肺炎链球菌对青霉素和头孢二代抗菌药物不敏感率为29%~36%,对大环内酯类耐药在90%左右,未发现对氟喹诺酮类耐药菌株。     

抗菌药物管理初期广州地区儿童肺炎链球菌及流感嗜血杆菌耐药性变迁

目的：为了解广州地区抗菌药物管理初期近10年下呼吸道住院病人分离的肺炎链球菌及流感嗜血杆菌耐药性的变迁。方法将3个不同时期[2003年6月—2004年12月(第1期)、2006年2月—2007年2月(第2期)、2011年1月—2012年6月(第3期)],下呼吸道感染病人痰标本进行细菌培养,用Etest检测及K-B法纸片对其中分离出的肺炎链球菌和流感嗜血杆菌进行常用抗菌药物的耐药性情况检测,分析比较3个时期的检测结果。结果3个时期肺炎链球菌培养结果分别为第1期172株,第2期79株,第3期391株;耐药性变化趋势中,青霉素、头孢呋辛、红霉素、克林霉素耐药性呈现上升趋势,且3个时期耐药性差异有统计学意义(均为P<0.001)。3个时期流感嗜血杆菌培养结果分别为第1期484株,第2期140株,第3期524株;耐药性变化趋势中,氨苄西林、阿莫西林/克拉维酸、头孢克洛、头孢呋辛、阿奇霉素耐药性呈现上升趋势,且3个时期耐药差异有统计学意义(均为P<0.001);四环素、头孢曲松耐药性呈现下降趋势,且3个时期耐药差异有统计学意义(均为P<0.001)。结论近10年中,肺炎链球菌对儿科常用抗菌药物包括青霉素、头孢呋辛、红霉素、克林霉素的耐药情况仍在上升趋势中。流感嗜血杆菌对氨苄西林、阿莫西林/克拉维酸、头孢克洛、头孢呋辛、阿奇霉素的耐药情况也是逐年加重;对头孢曲松的耐药性呈下降趋势。     

成人社区获得性肺炎病原菌耐药状况前瞻性研究

目的了解深圳地区成人社区获得性肺炎病原耐药情况．为经验治疗提供依据。方法以前瞻性研究方法,收集深圳地区40例成人社区获得性肺炎患者留取痰标本,进行细菌培养及药物敏感试验分析．采用血清学方法检测非典型病原体。结果肺炎链球菌时青霉素G敏感率为81.8％,头孢丙烯、头孢曲松、头孢吡肟、厄他配南和莫西沙星的敏感率均为100％,大环内酯类耐药率很高,阿奇霉素耐药率高达100％。流感嗜血杆菌对阿莫西林、头孢克洛、头孢丙烯、头孢曲松、头孢吡肟和加替沙星的敏感率均为100％,头孢地尼敏感率为87．5％,大环内酯类耐药率高。结论肺炎链球菌对青霉素G敏感率下降,大环内酯类耐药率高,头孢菌素敏感率较高。流感嗜血杆菌对阿莫西林、头孢菌素敏感率较高,大环内酯类耐药率高。     

2000～2002年北京、上海及广州三地儿童携带流感嗜血杆菌抗生素敏感性监测

目的了解当前我国儿童携带流感嗜血杆菌对常用抗生素的敏感性情况,以便有效指导临床合理用药和预防.方法采用E-test最小抑菌浓度 (MIC) 方法及KB纸片扩散法对2000～2002年北京、上海、广州3所儿童医院上呼吸道感染儿童携带流感嗜血杆菌进行10种常用抗生素敏感性检测.结果氨苄青霉素对898株流感嗜血杆菌的MIC50和MIC90分别为0.25 μg/ml和4 μg/ml,敏感性88.0%,10.6%菌株对氨苄青霉素耐药,所有氨苄青霉素中度敏感株和耐药株均产β-内酰胺酶,分离株产β-内酰胺酶率为12%;分离株对阿莫西林/克拉维酸、头孢曲松、头孢呋辛敏感性均为100%;头孢克罗对分离株MIC50和MIC90分别为1.5 μg/ml和3 μg/ml,敏感性略低(96.1%),耐药率1.8%.流感嗜血杆菌对阿奇霉素、环丙沙星敏感率分别为100%和99%,对氯霉素、四环素、磺胺甲(口恶)唑/甲氧苄氨嘧啶(SMZ/TMP)耐药率分别为11%、18%、54.4%.北京和上海分离株对四环素敏感性分别为57%和61%,明显低于广州分离株(81%);广州和上海分离株对SMZ/TMP敏感性分别为47%和54%,明显高于北京株(35%);2000～2002年的3年中,分离株对氨苄青霉素敏感性呈逐年下降趋势,对氨苄青霉素总体耐药率由2000年的7.7%增加至2002年的14.5%.本研究中,34.5%分离株对8种抗生素均敏感,多重耐药株占12.8%, 敏感株的分布有地区差异.58.5%的分离株分布在5个常见耐药表型中,其中单一SMZ/TMP耐药最多(29.8%);其次,SMZ/TMP和四环素交叉耐药(12.5%),单纯四环素耐药居第三位(9.4%).氨苄青霉素不敏感株对头孢克罗、四环素、SMZ/TMP和氯霉素耐药率分别为23.5%、63.3%、74.5%和63.3%,明显高于氨苄青霉素敏感株(1.6%、51.4%、11.1% 和4.9%);氨苄青霉素与头孢克罗对菌株MIC值呈正相关,与SMZ/TMP和氯霉素对菌株抑菌能力呈负相关.结论三地儿童携带流感嗜血杆菌的产酶率正在上升,导致菌株对氨苄青霉素耐药性增加,分离株对部分抗生素的耐药性有明显地域差异,菌株对氨苄青霉素耐药性与其对氯霉素、SMZ/TMP、头孢克罗耐药性有明显相关性.     

儿童呼吸道感染流感嗜血杆菌耐药分析

目的:了解贵州省遵义地区3岁以下儿童呼吸道感染流感嗜血杆菌(Haemophilusinfluenzae)的耐药情况,为儿童呼吸道感染流感嗜血杆菌的治疗提供依据。方法:对892例呼吸道感染患儿痰液标本进行分离培养并对其进行鉴定,用K-B法进行药物敏感试验。结果:对892例呼吸道感染患儿中分离出93株流感嗜血杆菌进行药物敏感试验表明,对氨苄西林的耐药率为44.1%;对复方新诺明的耐药率为64.5%;对头孢呋辛的耐药率为10.7%;对左氧氟沙星的耐药率为1%;对头孢曲松的耐药率为16.1%;对阿奇霉素的耐药率为6.5%;对氨苄西林/克拉维酸的耐药率为12.9%。结论:贵州省遵义地区3岁以下儿童呼吸道感染流感嗜血杆菌菌株对氨苄西林和复方新诺明的耐药率较高,对头孢呋辛、氨苄西林/克拉维酸、头孢曲松、阿奇霉素和左氧氟沙星的耐药率较低。临床上治疗尽量避免使用耐药率高的抗菌素。     

118株肺炎链球菌耐药性分析

目的：研究肺炎链球菌的耐药性。方法：118株肺炎链球菌为临床送检标本,药敏检测方法采用纸片扩散法（K-B法）。用E-test法检测青霉素对所有菌群的最低抑菌浓度（MIC）。结果：118株肺炎链球菌中16株为青霉素敏感株,中度耐药株34株,耐药株68株;肺炎链球菌对万古霉素全部敏感,未查见不敏感株;对头孢呋辛、头孢曲松、左氧氟沙星和氯霉素的耐药率较低;而对青霉素、红霉素和复方磺胺甲唑则耐药率较高;对青霉素不敏感菌株的耐药性强于青霉素敏感者,尤其是对红霉素、头孢呋辛和头孢曲松。结论：对青霉素不敏感菌株的耐药性强于青霉素敏感者,尤其是对红霉素、头孢呋辛和头孢曲松。     

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.