高脂饮食诱导的非酒精性脂肪性肝病大鼠肝组织PPARα和CPT—ⅠmRNA的表达

[目的]探讨过氧化物酶体增殖物激活受体(PPAR)α和肉碱棕榈酰转移酶(CPT-Ⅰ)在高脂饮食诱导的非酒精性脂肪性肝病(NAFLD)大鼠肝组织中的表达及其意义。[方法]模型组SD大鼠给予高脂饲料喂养,对照组大鼠予以普通饲料喂养,12周末处死,HE染色,光镜下观察各组大鼠肝组织的病理改变;测定肝组织匀浆中CHO、TG含量;用自动生化分析仪检测血清ALT、AST、CHO、TG、LDL-C和HDL-C水平,比色法检测血清FFA含量,放免法测定血清TNF-α含量;以RT-PCR法检测大鼠肝组织中PPARαmRNA和CPT-ⅠmRNA表达。[结果]模型组大鼠血清ALT、AST、FFA及TNF-α水平显著高于正常对照组(P<0.01),血清CHO、TG、LDL-C水平和肝匀浆CHO、TG的含量也较正常对照组显著增高(P<0.05,P<0.01),而血清HDL-C明显低于正常对照组(P<0.01);模型组大鼠脂肪变程度积分和炎症较正常组明显升高(P<0.01),而肝组织PPARαmRNA和CPT-ⅠmRNA的表达水平则显著下降(P<0.01)。[结论]持续12周的高脂饮食可以诱导NAFLD大鼠模型,模型组大鼠肝组织PPARαmRNA和CPT-ⅠmRNA的表达降低,在肝细胞成脂性改变中起重要作用。     

高脂饮食诱导的非酒精性脂肪性肝病大鼠肝组织PPARα和CPT-I mRN A的表达

[目的]探讨过氧化物酶体增殖物激活受体(PPAR)α和肉碱棕榈酰转移酶(CPT-I)在高脂饮食诱导的非酒精性脂肪性肝病(NAFLD)大鼠肝组织中的表达及其意义.[方法]模型组SD大鼠给予高脂饲料喂养,对照组大鼠予以普通饲料喂养,12周末处死,HE染色,光镜下观察各组大鼠肝组织的病理改变;测定肝组织匀浆中CHO、TG含量;用自动生化分析仪检测血清ALT、AST、CHO、TG、LDL-C和HDL-C水平,比色法检测血清FFA含量,放免法测定血清TNF-α含量;以RT-PCR法检测大鼠肝组织中PPARαmRNA和CPT-I mRNA表达.[结果]模型组大鼠血清ALT、AST、FFA及TNF-α水平显著高于正常对照组(P＜0.01),血清CHO、TG、LDL-C水平和肝匀浆CHO、TG的含量也较正常对照组显著增高(P＜0.05,P＜0.01),而血清HDL-C明显低于正常对照组(P＜0.01);模型组大鼠脂肪变程度积分和炎症较正常组明显升高(P＜0.01),而肝组织PPARαmRNA和CPT-I mRNA的表达水平则显著下降(P＜0.01).[结论]持续12周的高脂饮食可以诱导NAFLD大鼠模型,模型组大鼠肝组织PPARαmRNA和CPT-I mRNA的表达降低,在肝细胞成脂性改变中起重要作用.     

山楂叶总黄酮防治非酒精性脂肪性肝炎的研究

[目的]观察山楂叶总黄酮(TFHL)抗大鼠非酒精性脂肪性肝炎(NASH)的作用。[方法]采用高脂饲料喂养12周建立大鼠NASH模型,以250、125mg/kg体重/d的TFHL及易善复进行预防和治疗,分别在预防12周及治疗8周后观察肝组织病理学改变,血清FFA、TG、CHOL、HDL-C、LDL-C、ALT、AST水平及肝组织匀浆TG、CHOL的含量。[结果]模型大鼠肝组织出现了严重脂肪变和不同程度炎症细胞浸润,肝细胞坏死,脂质代谢紊乱,肝脏脂质大量堆积。应用TFHL及易善复进行预防和治疗后,大鼠肝组织脂肪变程度和炎症活动程度较模型大鼠显著降低,肝脏脂质含量较模型大鼠显著降低。[结论]TFHL能调节脂质代谢紊乱,对高脂饮食诱导的NASH有较好的防治作用。     

丹参对非酒精性脂肪性肝炎大鼠脂质代谢及脂肪细胞因子影响

目的:观察丹参注射液对非酒精性脂肪性肝炎大鼠脂质代谢、肝组织病理变化及脂肪细胞因子的影响,探讨其防治非酒精性脂肪性肝炎(Non-alcoholic steato-hepatitis,NASH)的可能作用机制。方法:采用高脂饮食16周建立大鼠非酒精性脂肪性肝炎模型,并用丹参注射液5 m L/(kg·d)进行干预治疗,观察各组大鼠肝湿质量、肝指数,血清及肝组织匀浆TG、TC含量,HE染色光镜观察肝组织脂肪变和炎症程度,ELISA法检测血清脂联素、TNF-α水平。结果:模型组大鼠肝湿质量、肝指数,血清及肝组织匀浆TG、TC含量升高,血清TNF-α水平升高,脂联素水平下降,肝组织炎症积分升高(P0.01);丹参治疗后肝组织炎症程度较模型组明显减轻,血清及肝组织匀浆TG、TC含量较模型组明显降低,血清脂联素水平较模型组增高,TNF-α水平较模型组显著下降(P0.01)。结论:丹参注射液能通过上调脂联素水平、下调TNF-α水平,降低肝脏脂质蓄积,从而抑制肝细胞炎症,防止NASH的进展。     

非酒精性脂肪性肝炎形成中脂肪细胞因子的动态变化及意义

目的:研究非酒精性脂肪性肝炎(NASH)形成中脂肪细胞因子的动态变化特征。方法:SD大鼠40只,随机分成正常组10只,模型组30只;正常组大鼠以标准饲料喂养,模型组以高脂饲料喂养。模型组大鼠分别在实验开始后4、8、12周末3个时相点分批随机处死10只,正常组全部在12周末处死。采用HE染色观察肝组织病理组织学变化,ELISA法检测血清及肝组织TNF-α、Leptin、IL-6、ADP水平。结果:病理组织学表明,高脂喂养4周大鼠表现为单纯性脂肪肝;8周时脂肪变程度加重,有少量炎细胞浸润;12周时大鼠NASH形成。模型组大鼠从4周到8、12周,血清和肝组织TNF-α、IL-6水平及血清Leptin水平逐渐增高,而血清ADP水平则逐渐减少;模型组4周末血及肝组织TNF-α、IL-6、Leptin、ADP水平与正常组比较差异无统计学意义(P>0.05),而12周末血和肝组织TNF-α、IL-6水平及血清Leptin、ADP水平均比正常组明显增高或降低(P<0.05,P<0.01)。结论:脂肪细胞因子的过度表达或异常缺失参与了NASH的发生、发展。     

清肝化痰活血方对非酒精性脂肪性肝炎模型大鼠的干预作用

目的观察清肝化痰活血方对非酒精性脂肪性肝炎(NASH)模型大鼠的影响,并探讨其作用机制。方法雄性SD大鼠36只分为对照组6只、模型组10只、清肝化痰活血方干预组(清肝组)10只、胆宁片干预组(胆宁组)10只。对照组普通饲料喂养;其余3组均采用高脂饮食复制NASH动物模型,清肝组、胆宁组分别给予清肝化痰活血方药液和胆宁片混悬液灌胃,对照组和模型组同时予生理盐水灌胃。造模12周末处死各组大鼠,检测体质量、肝指数、炎症活动度计分、血清丙氨酸氨基转氨酶(ALT)、门冬氨酸氨基转氨酶(AST)、γ-谷氨酰转移酶(γ-GT)、总胆固醇(TC)、甘油三酯(TG)、游离脂肪酸(FFA)含量和肝组织中TG、FFA、丙二醛(MDA)含量、超氧化物歧化酶(SOD)活性。结果第12周时模型组和胆宁组大鼠体质量、肝指数、炎症活动度计分、血清AST、ALT、γ-GT、TG、TC、FFA水平、肝组织TG、MDA、FFA含量均高于对照组和清肝组(P<0.05),SOD活性均低于对照组和清肝组(P<0.05);胆宁组体质量、肝指数、炎症活动度计分及血清ALT、TG、TC和FFA水平、肝组织TG、FFA均较模型组降低(P<0.05);与对照组比较,清肝组炎症活动度计分、血清TG增高(P<0.05),肝组织SOD活性降低(P<0.05)。结论清肝化痰活血方对NASH模型大鼠有良好的防治作用,其作用机制可能是通过调节脂质代谢,减轻脂类在肝脏的积聚,抗脂质过氧化,缓解氧化应激。     

三七对酒精性脂肪肝大鼠血清TNF-α、Leptin水平的影响

目的:观察三七对酒精性脂肪肝大鼠血清TNF-α、Leptin水平的影响.方法:62只大鼠随机分为正常组10只,模型组、易善复组、三七大、小剂量组各13只;模型组大鼠2次/日采用50%酒精灌胃,同时每天自由饮用10%酒精饮料进行造模,易善复组、三七大、小剂量组大鼠在造模的同时予相应的药物进行干预,连续14周后观察肝组织的病理学改变,放免法测定血清中TNF-α、Leptin含量.结果:模型组大鼠肝组织出现不同程度的肝脂肪变性,血清中TNF-α、Leptin含量较正常组明显升高,应用三七大、小剂量干预后,大鼠肝组织脂肪变明显减轻,血清TNF-α、Leptin含量明显降低,与模型组比差异均有显著性意义(P＜0.05).结论:三七降低血清TNF-α、Leptin的水平可能是其有效防止酒精性脂肪肝发生的重要机制之一.     

三七对酒精性肝病防治作用的研究

目的 观察三七对酒精性肝病的防治作用.方法 70只SD雄性大鼠随机分为正常组10只,模型组、三七高剂量组、三七低剂量组和硫普罗宁组各15只;以56度红星二锅头5g/(kg·d)、玉米油2ml/(kg·d)和吡唑27.2 mg/(kg·d)每天1次灌胃,连续14周建立酒精性肝病模型,同时分别以1.2g/(kg·d)和0.6g/(kg·d)的三七粉和100mg/(kg·d)的硫普罗宁灌胃进行干预,均连续14周.全自动生化仪测定各组大鼠血脂、血清肝功能水平,ELISA法检测透明质酸(HA)、层黏蛋白(LN)含量,常规HE及Masson染色光镜观察肝组织的脂肪变、炎症及纤维化程度.结果 模型组大鼠肝组织脂肪变及炎症程度、血清CHOL、HDL-C、LDL-C、AST、ALT、HA、LN水平均较正常组明显增高(P＜0.01,P＜0.05),但血清TG水平则无明显升高(P＞0.05).三七高低剂量组、硫普罗宁组大鼠肝组织脂肪变及炎症程度、血清AST、ALT、血清HA、LN水平较模型组明显减轻(P＜0.01,P＜0.05),但血清TG、CHOL、HDL-C、LDL-C水平与模型组比差异无显著性差(P＞0.05).结论 (1)采用白酒-玉米油-吡唑混合液灌服大鼠14周能成功复制ALD模型,表现肝组织脂肪变和炎细胞浸润、血脂紊乱、血清肝功能及肝纤维化指标升高.(2)三七可明显减轻酒精性肝病大鼠肝组织脂肪变和炎症程度,改善血清肝功能和纤维化指标.     

枳棋子水提取液治疗非酒精性脂肪性肝炎的实验研究

目的:观察枳棋子水提取液对实验大鼠非酒精性脂肪性肝炎(NASH)的治疗作用.方法:用高脂饲料诱导非酒精性脂肪性肝炎大鼠模型8周后,灌服枳棋子水提取液治疗2周,观察对模型大鼠肝脏病理脂肪变、炎症程度及血清ALT、AST、TNF-α、IL-8、FFA、胰岛素敏感性指标(ISI)和肝组织MDA、SOD的影响,并与凯西莱联合易善复治疗进行比较.结果:枳椇子能明显减轻模型大鼠肝脏炎症和脂肪变程度(P<0.01);降低血清ALT、AST、TNF-α、IL-8、FFA、肝组织MDA、SOD、提高ISI(P<0.01或P<0.05).除肝组织MDA、SOD外,其它指标均明显优于对照组(P<0.05).结论:枳棋子水提取液对高脂饲料诱导的大鼠NASH有明显的治疗作用,效果优于凯西莱联合易善复治疗,其作用机制可能与提高胰岛素敏感性、抗氧化、抑制炎症细胞因子等有关.     

舒肝活血化痰方干预大鼠脂肪性肝炎的实验研究

目的：探讨舒肝活血化痰方干预大鼠高脂血症性脂肪性肝炎的疗效及作用机制。方法：采用高脂饮食复制高脂血症性脂肪性肝炎大鼠模型，用活血化痰利湿方治疗，以东宝肝泰为对照，观察其对模型大鼠血清肝功能、血脂、肝组织超氧化物歧化酶(SOD)活性、丙二醛(MDA)含量、肝组织羟脯氨酸(Hyp)含量和细胞色素P450 2E1(Cytochrome P450 2E1。CYP2E1)活性影响。结果：舒肝活血化痰方显著改善肝功能。降低血清TG、TC、及LDL—C的同时升高HDL-C含量，并有显著降低肝组织Hyp含量，抑制肝组织CYP 2E1活性的作用。结论：舒肝活血化痰方可有效干预大鼠高脂血症性脂肪性肝炎，抑制肝组织CYP2E1的表达及与其密切相关的脂质过氧化是该方干预作用的主要机制之一。     

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.