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21.
Baruffi RL Mauri AL Petersen CG Ferreira RC Coelho J Franco JG 《Journal of assisted reproduction and genetics》2000,17(10):557-560
Purpose: Zona thinning (ZT) is a technique used to improve pregnancy rates among patients 38 years old and/or patients presenting previous implantation failure. The objective of the study was to determine whether ZT has a beneficial effect on patients younger than 37 years who are undergoing the first ICSI attempt.
Methods: A total of 103 patients submitted to ICSI for the first time and those aged 37 years were divided in a prospective and randomized manner into two groups: group I, patients submitted to ZT (n = 51) (a laser diode with 1.48-m wavelength (Fertilaser) was used for the procedure); group II, patients with no ZT (n = 52). In both groups, embryo transfer was performed on the second day.
Results: The age of group I patients (31.8 ± 3.6) did not differ (P = 0.53) from that of group II patients (31.4 ± 3.6). The number of metaphase II oocytes was similar(P = 0.76) for the two groups (group I = 9.12 ± 5.27; group II = 8.67 ± 5.02). The average number of embryos available per transfer of group I (6.14 ± 4.02) did not differ (P = 0.69) from that of group II (5.75 ± 3.83). The number of embryos transferred was similar (P = 0.61) for the two groups (group I = 2.76 ± 0.9; group II = 2.87 ± 0.79). The thickness of the zona pellucida of group I embryos (16.6 ± 2.2 m) did not differ (P = 0.08) from that of group II embryos (17.1 ± 1.7 m). The rate of embryo implantation (20.8%) and the rate of clinical pregnancy per embryo transfer (40.3%) were higher for group II than for group I (17.7% and 33.3%, respectively), but the difference was not significant (P = 0.55 and P = 0.54).
Conclusions: These results suggest that ZT in the population aged 37 years and with no previous failure of implantation may have no impact on intracytoplasmic sperm injection success rates. 相似文献
22.
Tetsuya Morishita Motofumi Yokoyama Masahiro Nozaki Masatoshi Sano Hitoo Nakano 《Journal of assisted reproduction and genetics》1993,10(7):463-467
Purpose Although the hatching of embryos is an important phenomenon, the mechanism of hatching remains controversial. Therefore, we attempted to develop a new coculture system with human placental cells to investigate the hatching of mouse embryos.Results In our new system there was no difference in development from the two-cell stage to blastocysts between embryos cultured with a T6 medium and embryos cocultured with human placental cells at 1 × 105, 5 × 105, and 1 × 106 cells/ml. However, the hatching-rate cell number increased significantly in embryos cocultured with placental cells compared to embryos cultured without placental cells. [3H]Thymidine uptake did not show any significant difference from the beginning of in vitro culture to the hatching stage between the coculture group and the control group. Nevertheless, the [3H]uridine uptake was significantly different in the two groups, measuring 2167 ± 532 cpm/10 embryos in the coculture group and 804 ± 86 cpm/10 embryos in the control group at 114 hr after human chorionic gonadotropin injection (P < 0.01).Conclusion These results therefore seem to indicate that the hatching of blastocysts depends on the protein synthesis of the embryos and not on DNA duplications. 相似文献
23.
Park S Kim EY Yoon SH Chung KS Lim JH 《Journal of assisted reproduction and genetics》1999,16(2):97-101
Purpose:
Our purpose was to test whether zona pellucida (ZP) drilling using a 1.48-m diode laser beam on bovine IVM/IVF/IVC blastocysts is effective for embryo hatching.
Methods:
Blastocysts produced in vitro at day 7 after IVF were divided into control and laser-drilled groups, respectively.
Results:
When the rates of in vitro development of bovine embryos were examined, the average cleavage rate (>two-cell) was 82.3% and the blastocyst rate at day 7 after IVF was 32.5%. Using these blastocysts, when the laser drilling effect was investigated at 48 hr after treatment, the total hatching rate in the laser-drilled group (98.0%) was significantly higher than that in the control group (60.0%)(P < 0.001). Especially, the hatched rate of the laser-drilled group (68.0%) was significantly enhanced compared with that of the control group (30.0%) (P < 0.001).
Conclusions:
These results demonstrated that laser ZP drilling on bovine IVM/IVF/IVC blastocysts can significantly increase the hatching rate. 相似文献
24.
Annette Gomot 《Ecotoxicology and environmental safety》1998,41(3):288-297
The freshwater snailLymnaea stagnaliswas exposed to cadmium concentrations of 0, 25, 50, 100, 200, and 400 μg liter−1. The influence of this highly toxic metal on various stages of reproduction (number of egg masses, number of eggs, embryo development, and hatching) was studied. Egg production ceased at 400 μg Cd2+liter−1and hatching was reduced to 0.4% with 200 μg liter−1at 20°C. The study revealed that embryo development was the most sensitive stage, the main anomalies observed depending on the Cd2+concentration. At the highest concentration studied (400 μg liter−1) the eggs were blocked in the first cleavage stage. At 100 and 200 μg Cd2+liter−1, development of the eggs was halted at various stages of embryogenesis (cleavage, gastrula, veliger, and prehatching) depending on their position in the egg masses. At concentrations of 25 to 100 μg Cd2+liter−1, development was slowed down and hatching occurred 5 to 15 days later than in the controls (controls hatched 12 to 13 days after laying). The results obtained demonstrate the effects of Cd2+on reproduction and development inL. stagnalisand provide information on the targets affected (neuroendocrine control of laying or cell multiplication and organogenesis of the embryos). It is thus possible to predict the probability of survival of the species in an environment polluted with cadmium and to compare it with the effects of other pollutants in the same or other species. 相似文献
25.
Williams CA Wallace MR Drury KC Kipersztok S Edwards RK Williams RS Haller MJ Schatz DA Silverstein JH Gray BA Zori RT 《Human reproduction (Oxford, England)》2004,19(12):2816-2821
We report on dizygotic (DZ) twins, conceived by IVF and ICSI with assisted hatching, who each had a mixture of 46,XX and 46,XY cells in blood lymphocytes. The female twin had mild genitalia abnormalities but further study revealed anatomically normal reproductive anatomy. Chromosome and fluorescence in situ hybridization studies of buccal, skin and ovarian tissue were normal, as were buccal tissue DNA studies. Fetal ultrasound and fetal membrane pathology were consistent with a monochorionic, diamniotic placenta (MCDAP). These twins thus have blood chimerism but are not chimeric in the other tissues studied. The mechanism for the chimerism could be due to either placental vascular anastamoses (after the development of the haematoblast stem cells) or due to an admixture of trophoblast cells during early blastocyst development. Such trophoblast cell admixtures would be restricted to the extraembryonic tissues so that general physical development in the fetus is normal and without somatic cell chimerism. This case in combination with others previously reported suggests that in IVF conceptions, the prevalence of blood chimerism associated with twinning, and the occurrence of DZ twinning associated with MCDAP, may be higher than previously thought. 相似文献
26.
口咽狭窄所致OSAS两种手术方法的疗效比较 总被引:5,自引:2,他引:3
目的;比较研究阻塞性睡眠呼吸暂停综合征(OSAS)患者行腭咽成形术(UPPP)和扁桃体剥离加激光辅助悬雍垂软腭成形术(LAUP)的疗效。 相似文献
27.
目的探讨激光辅助孵化(laser-assisted hatching,LAH)对反复种植失败及冻融胚胎移植(frozen-thawed embryos,FET)患者的临床妊娠结局的影响。方法收集反复种植失败的患者100例,随机分为LAH组1与对照组1,FET患者200例,随机分为LAH组2与对照组2,LAH组1与LAH组2患者移植前进行LAH。结果 LAH组1患者的临床妊娠率及胚胎种植率均高于对照组1,(分别是44%vs 28%,P>0.05,25%vs 11.33%,P=0.003),两组患者的早期流产率及双胎率均无明显差异。LAH组2患者的临床妊娠率及胚胎种植率与对照组2比较均无明显差异(分别是37%vs 38%,P=0.884;19.17%vs16.50%,P=0.50)。LAH组2患者的早期流产率及双胎妊娠率高于对照组2,但无统计学意义。结论 LAH可改善反复种植失败患者的妊娠结局;对年轻的FET患者妊娠结局无明显影响,不宜对所有FET患者常规进行LAH治疗。 相似文献
28.
In 19 patients with insufficient hemodialysis access fistulas combined laser and balloon angioplasty of two occlusions and 17 stenoses of the shunt vein was performed. In 13 of those 19 cases the procedure was preceded by balloon angioplasty, which was insufficient because of resistant subintimal fibrosis. After using the pulsed dye laser a complete dilatation was possible in all cases.The new method is a valuable addition to percutaneous interventional techniques in patients with shunt problems, and better long term results may be expected in selected cases.
Offprint requests to: E. Gmelin 相似文献
29.
水牛体外受精胚胎的玻璃化冷冻 总被引:2,自引:0,他引:2
本文以ES35为玻璃化冷冻液 ,ES2 0和 30 %乙二醇为前处理液 ,进行不同时间的前处理 ,初步探讨了水牛体外受精胚胎的玻璃化冷冻保存方法。结果 4个处理组中以ES2 0前处理 2min组冷冻效果最好 ,其冻胚解冻后孵化率达 6 4 .4 1% ,30 %乙二醇前处理 5min组孵化率为 5 7.4 1% ,两组与对照组差异不显著 ,其余两组与对照组差异极显著 ;ES2 0前处理中 2min组与 5min组差异极显著 (6 4 .4 1%vs2 1.15 % ,P <0 .0 1) ;30 %乙二醇前处理中 5min组极显著高于 2min组 (5 7.4 1%vs2 3.6 4 % ,P <0 .0 1) ;取ES2 0前处理 2min组的冻胚移植了 5头本地母水牛 ,结果有一头妊娠。于 2 0 0 2年 12月 6日产下全国首例冻胚移植的试管水牛 相似文献
30.
Yuji Endo Shingo Mitsuhata Momoko Hayashi Yoshitaka Fujii Hiroaki Motoyama 《Reproductive Medicine and Biology》2021,20(2):182-189
PurposeThis study determined the effect of laser‐assisted hatching on the clinical and neonatal outcomes of single vitrified blastocyst transfer.MethodsFrom June 2014 to March 2018, 289 matched pairs after propensity score matching were analyzed. During the blastocyst warming procedure, a small section of the zona pellucida area in the empty perivitelline space was sliced off using multiple laser beams. The clinical and neonatal outcomes of the laser‐treated group and non‐treatment control were analyzed.ResultsIn the laser‐assisted hatching group, significantly higher rates of clinical pregnancy (40.8% vs 29.4%, P < .01) and live delivery (34.3% vs 22.5%, P < .01) were observed compared to the control group. Other variables such as the average gestational weeks, the sex of the baby, birthweight, or congenital malformations were found to have no significant differences in neonatal outcomes. Moreover, all babies were singleton live births.ConclusionsSingle vitrified blastocyst transfer treated with laser‐assisted hatching increases the live birth rate and has no adverse effects on neonatal outcomes. 相似文献