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1.
《Medical Journal Armed Forces India》2022,78(1):7-16
Oocyte and embryo grading is one of the most important steps in assisted reproductive technology to identify the best among cultured embryos for transfer or vitrification. The most commonly used non-invasive method is morphological assessment of gametes and embryos using a microscope. This method despite being simple and cost-effective has interobserver and intraobserver variability and subjectivity and has little to offer about the physiological state of embryos. This review sourced research articles and reviews pertaining to other non-invasive assessment methodologies from Medline and PubMed to collate latest technologies in vogue and identify novel methodologies of the future. The review assesses the current understanding in oocyte and embryo grading and touches upon novel non-invasive techniques and potential biomarkers to identify the best embryo. The latest available literature on time-lapse imaging, hierarchical algorithms, omics (consisting of proteomics and secretomes), miRNAs, mitochondrial RNAs and artificial intelligence has been accessed to summarize the enormous information available, to identify gaps in current interpretations, to identify emerging technologies and to provide direction for future research. This review will greatly benefit anyone practicing assisted reproduction and clinical embryology. 相似文献
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3.
目的 探究下颌磨牙区即拔即种的临床疗效。方法 选取2017年1月至2019年1月江门市口腔医院收治的60例需进行下颌磨牙区种植的患者随机分为A、B组,A组给予即拔即种,B组给予延期种植,比较两组留存率、浅蝶形骨吸收率、种植12个月后PIS指标及满意度进行评价。结果 随访12个月两组留存率均为100%,浅碟形骨吸收率A组前磨牙为16.67%、磨牙为22.22%,B组前磨牙为10.00%、磨牙为25.00%,差异均无统计学意义(P>0.05),A组植入30个种植体,60个牙间乳头,其中3度29个、2度24个、1度7个,B组植入30个种植体,60个牙间乳头,其中3度14个、2度24个、1度22个,A组牙间乳头PIS指标优于B组,且A组牙间乳头PIS评分(2.36±0.52)较B组(1.87±0.48)显著提高,差异均具有统计学意义(P<0.05),A组对治疗效果满意率为93.33%较B组66.67%显著提高,差异具有统计学意义(P<0.05)。结论 对于下颌磨牙区缺牙患者可采取即拔即种的方法修复,缩短缺牙时间,促进咬合和咀嚼功能恢复,舒适且美观,提高患者的满意度,值得在临床上推广。 相似文献
4.
J.I. Smedberg E. Lothigius I. Bodin A. Frykholm K. Nilner 《Clinical oral implants research》1993,4(1):39-46
In order to satisfy the need to restore the aesthetics, phonetics and comfort and to facilitate optimal hygiene procedures, 20 edentulous patients were treated with a new concept of overdenture therapy on implants ad modum Brånemark. After 24±3.5 months the patients were re‐examined. They were asked to answer a questionnaire and use a Visual Analogue Scale (VAS) to give their opinion on the prosthetic treatment. The results indicate that an implant‐retained overdenture in the maxilla with this design can satisfy the patients needs in aesthetics, phonetics and comfort and can 1 facilitate oral hygiene measures. 相似文献
5.
Zhe-ping HUANG Jian WANG Wei-xiong SHEN Ping HUANG Jia-ke TSO Qing-xiang SHEN 《生殖与避孕(英文版)》2002,13(4)
Objective To identify genes that may be related to embryo implantation Materials & Methods The PCR subtraction technique was applied at implantation and inter-plantation sites on day 4. 5 of pregnancy in mice. Two novel Expressed Sequence Tags (ESTs ), EST8 and EST81 were identified; their expression in tissues was analyzed by Northern blotting, and their full-length cDNAs were synthesized by PCR.Results We found that these two novel ESTs (EST8and EST81) were noticeably expressed in implantation site in the mouse on day 4. 5 of pregnancy. EST8 was expressed at high level in livers and implantation sites of the mice, while at low level in ovaries and inter-plantation sites. EST81 was predominantly expressed in implantation site and ovary, and at low level in all other tissues. Their complete cDNAs, 1 665bp and 1 264 bp respectively, were synthesized by using PCR.Conclusion The two full-length cDNAs were responsible for embryo implantation,and their functions need to be further studied. 相似文献
6.
Priv.-Doz. Dr. Rüdiger Dissmann Joachim Schröder MD PhD Prof. Dr. med. Heinz Völler Prof. Dr. med. Steffen Behrens 《Clinical research in cardiology》2006,95(4):241-243
Summary During pacemaker implantation in a patient with permanent atrial fibrillation, it remained impossible to advance a passive
fixation lead with fins through the right atrium. However, a lead with a retractable screw easily passed the right atrium
and was positioned in the right ventricle. Transesophageal echocardiography revealed an extensive net–like perforated Eustachian
valve within the right atrium that had caused entrapment of the anchor fins during lead implantation. Remnants of embryonal
structures within the right atrium should be considered a rare possible barrier during pacemaker implantation. 相似文献
7.
以钒基核苷酸复合物为核酸酶抑制剂,从人胚组织中制备总RNA,所得产品几乎不含DNA和蛋白质,经过分离Poly(A)~ mRNA,证明制品有合成cDNA的完整功能,方法比较简捷,适于大量制备以满足分离mRNA 之需,并讨论了此法的优缺点。 相似文献
8.
立体着床模型--小鼠囊胚与子宫内膜的共培养 总被引:1,自引:0,他引:1
目的:建立小鼠囊胚体外着床的三维模型,为着床机制的研究提供重要工具.方法:将小鼠囊胚与其自身子宫内膜分别共培养在空气、含500,750和950 mL/L O2的混合气体与组织培养液的气液界面上,比较不同O2浓度下小鼠囊胚的贴附率,确定体外共培养的最佳O2浓度;同时将确认有囊胚贴附的子宫内膜取出作HE染色.结果:不同O2浓度下,囊胚的贴附率分别为64.75%,47.86%,42.37%和30.97%,x2检验提示其差异有显著性(x2=28.145,P=0.000);且随着混合气体中O2浓度的逐渐升高,囊胚贴附率呈逐渐降低趋势.因此50 mL/L CO2 950 mL/L空气对囊胚与子宫内膜的共培养是最有利的;同时,囊胚贴附子宫内膜后并无扩展行为而是直接侵入子宫内膜.结论:50 mL/L CO2 950 mL/L空气最有利于囊胚与子宫内膜的共培养;且囊胚贴附子宫内膜后不发生外延生长,而是直接侵入子宫内膜.本实验成功地建立了小鼠囊胚体外着床的三维模型. 相似文献
9.
Portsite and intraabdominal metastases of unsuspected gallbladder carcinoma after laparoscopic cholecystectomy: Report of a case 总被引:1,自引:0,他引:1
Nobuhiro Shibata Katsumi Kagotani Sadao Noguchi Masamitsu Tamai 《Surgery today》1996,26(12):1014-1016
We herein report a rare case of portsite metastasis of gallbladder carcinoma which occurred after laparoscopic cholecystectomy. A 64-year-old man underwent laparoscopic cholecystectomy at another hospital for symptomatic cholecystolithiasis. The histological examination revealed an adenocarcinoma of the gallbladder infiltrating the entire wall. Despite the physician's advice the patient refused any additional treatment. Thirteen months after surgery he visited our hospital because of a palpable mass at the scar of the right trocar incision. The nodule was removed and histological examination confirmed metastasis from the gallbladder carcinoma. 相似文献
10.
R. Lazzara A. A. Siddiqui P. Binon S. A. Feldman R. Weiner R. Phillips A. Gonshor 《Clinical oral implants research》1996,7(1):73-83
Osseointegrated dental implants have now become an accepted form of treatment for patients with a fully or partially missing dentition. The purpose of this study was to evaluate the performance of 3i threaded and cylindrical implants. During a 5-year period, a total of 1969 3i endosseous implants were placed at 6 centers in the United States and 2 elsewhere in the edentulous and partially edentulous jaws of 653 consecutive patients ranging in age from 18 to 82 years. Of the total number of implants placed, 1341 were commercially pure titanium threaded implants and 628 were titanium plasma-sprayed implants with a cylindrical configuration. A total of 28 patients with 110 implants were lost to follow-up. Implants in these patients were considered neither a success nor a failure. Success was predicated on the osseointegration of each and every implant followed in this analysis rather than the persistence of prosthetic function. Confirmed bone anchorage was considered essential for success. A total of 625 patients with 1871 implants remain in the study with a follow-up period ranging from 6 to 60 months. A total of 93 implants (5.0% of the total implants followed) were considered as failures. A mean implant survival rate was 95.0% for both the threaded and the cylindrical implant was calculated. The success rate of threaded implants was 97.0% in the mandible and 93.8% in the maxilla. The success rate for the 3.3mm cylindrical implants was 96.0% in the mandible and 95.5% in the maxilla, and the success rate of 4.0mm diameter cylindrical implants was 95% in the mandible and 92.0% in the maxilla. Causes of failure consisted of loss of osseointegration 2.3%crestal bone loss requiring periodontal therapy after the first year of function 1.7% and mechanical problems associated with the prosthesis 0.9%. This retrospective analysis of the 3i endosseous implant system is comparable to previous reports on other implant systems in terms of implant survival and prosthesis stability. It is demonstrated that 3i implants are predictable and can provide lasting osseointegration leading to improvement of oral function if the recommended surgical and restorative protocol is followed. 相似文献