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Results 251 - 300 of 1205
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Lu Zhi Hong - - 2006
Three cold shock domain (CSD) family members (YB-1, MSY2, and MSY4) exist in vertebrate species ranging from frogs to humans. YB-1 is expressed throughout embryogenesis and is ubiquitously expressed in adult animals; it protects cells from senescence during periods of proliferative stress. YB-1-deficient embryos die unexpectedly late in embryogenesis (embryonic ...
Rubolini D - - 2006
Maternal effects mediated by egg quality are important sources of offspring phenotypic variation and can influence the course of evolutionary processes. Mothers allocate to the eggs diverse antioxidants that protect the embryo from oxidative stress. In the yellow-legged gull (Larus michahellis), yolk antioxidant capacity varied markedly among clutches and declined ...
Elibol O - - 2006
The effect of turning angle (from vertical) and the interaction with turning frequency during incubation on fertile hatchability, embryonic mortality, and the incidence of embryos with head in the small end of the egg (malpositioned) was studied in 2 experiments comprising 2 trials each to determine if a turning angle ...
Emiliani Serena - - 2006
The policy of single embryo transfer (SET) adopted for women <36 years old since 1 July 2003, strongly calls for improvement of embryo selection. A total of 196 cycles in which SET was performed were randomly allocated to two groups. In the first group, early cleavage was assessed (ECA) 25 ...
Sarkar Mihir - - 2006
An attempt was made to induce estrus and ovulation in eight anestrus yaks by use of the Ovsynch protocol. Six out of eight yaks were successfully induced into estrus, and ovulation occurred in all the responding yaks 1-2 days after the second GnRH administration. Out of the six animals that ...
Jones Rebecca L - - 2006
Transforming growth factor beta (TGFbeta) superfamily members are closely associated with tissue remodelling events and reproductive processes. This review summarises the current state of knowledge regarding the expression and actions of TGFbeta superfamily members in the uterus, during the menstrual cycle and establishment of pregnancy. TGFbetas and activin beta subunits ...
Arnold Daniel R - - 2006
Abnormal placental development limits success in ruminant pregnancies derived from somatic cell nuclear transfer (SCNT), due to reduction in placentome number and consequently, maternal/fetal exchange. In the primary stages of an epithelial-chorial association, the maternal/fetal interface is characterized by progressive endometrial invasion by specialized trophoblast binucleate/giant cells (TGC). We hypothesized ...
Wang Haibin - - 2006
Synchronized preimplantation embryo development and passage through the oviduct into the uterus are prerequisites for implantation, dysregulation of which often leads to pregnancy failure in women. Cannabinoid/endocannabinoid signaling via cannabinoid receptor CB1 is known to influence early pregnancy. Here we provide evidence that a critical balance between anandamide synthesis by ...
Ferretti Elisabetta - - 2006
The interaction of Prep1 and Pbx homeodomain transcription factors regulates their activity, nuclear localization, and likely, function in development. To understand the in vivo role of Prep1, we have analyzed an embryonic lethal hypomorphic mutant mouse (Prep1(i/i)). Prep1(i/i) embryos die at embryonic day 17.5 (E17.5) to birth with an overall ...
Boncoraglio Giuseppe - - 2006
Maternal hormones may represent an important pathway by which mothers can adaptively adjust offspring traits and performance to suit the prevailing environmental conditions. Earlier studies of birds have shown that egg androgens of maternal origin may enhance post-natal offspring 'begging' displays, functioning to solicit parental care. Here we investigate the ...
Keltz Martin D - - 2006
OBJECTIVE: To assess predictors of embryo fragmentation in IVF as well as to compare cycle outcomes between low-grade embryos subjected to defragmentation and high-grade embryos not undergoing defragmentation. DESIGN: A retrospective, case-control trial. SETTING: A university hospital IVF program. PATIENT(S): Three hundred twenty-seven nondonor, fresh IVF cycles. MAIN OUTCOME MEASURE(S): ...
Vieira A D - - 2007
The aim of this study was to determine the influence of two ethylene glycol-based vitrification solutions on in vitro and in vivo survival after in-straw cryoprotectant dilution of vitrified in vitro-produced bovine embryos. Day-7 expanded blastocysts were selected according to diameter (> or = 180 microm) and osmotic characteristics and ...
Donoso P - - 2006
BACKGROUND: An increased incidence of aneuploid embryos has been recently described from azoospermic men. The aim of this study was to assess if embryo selection on day 5, based on morphological criteria, would be different from the selection based on PGD for aneuploidy screening (AS) in couples undergoing ICSI for ...
Kim Deok-Ho - - 2006
During early development, the chorion envelope of the zebrafish embryo undergoes a thinning process called "chorion softening," which has so far only been characterized chemically. In this study, a micromechanical force sensing system was used to characterize and quantitate mechanical modifications of the zebrafish embryo chorion during early development. Quantitative ...
Galvão K N - - 2006
Objectives were to determine the effects of gossypol exposure during early embryo development on embryonic survival after transfer of frozen and thawed embryos to lactating dairy cows treated with human chorionic gonadotropin (hCG). Holstein cows (n = 269) were either treated or not treated with 3,300 IU of hCG on ...
Jaffar Ali
Objective: To perform a clinical trial to evaluate human embryos generated in the protein-free medium (PFM). Materials and methods: The quality of embryos generated in medium with (control; Medi-CultTM) and without protein (test; ART-7b) and their viability were compared. Sperm was prepared in control or test media as appropriate. Effect ...
Cieslak-Janzen Jeanine - - 2006
To determine the impact of multiple micromanipulation procedures for preimplantation genetic diagnosis (PGD) on embryo development, a retrospective analysis was performed of 9,925 embryos (862 PGD cycles), which were compared with 28,126 nonbiopsied embryos (2,751 consecutive intracytoplasmic sperm injection [ICSI] cycles) from the same time period. Because fertilization rates, the ...
Ortega-Pacheco A - - 2006
OBJECTIVES: To determine the prevalence of fetal resorption in 77 pregnant bitches and its association with the age, size and body condition score of the bitch and to determine the frequency of transuterine migration of embryos. METHODS: The number and position of embryos or fetuses and placental zones were registered ...
Bathgate R - - 2007
Embryos and offspring of a pre-determined sex have been produced in pigs using AI and IVF with unfrozen sperm, and after surgical insemination with sex-sorted frozen-thawed sperm. The aims of this study were to demonstrate that sex-sorted frozen-thawed boar sperm could be incorporated into pig IVF for the production of ...
Fassihi H - - 2006
Skin fragility-ectodermal dysplasia syndrome is an autosomal recessive disorder caused by loss-of-function mutations in the desmosomal protein, plakophilin 1. Clinically, there may be considerable morbidity from extensive skin erosions and painful fissures on the palms and soles. In the absence of any specific treatment, prenatal diagnosis is an option for ...
Tsutsui Toshihiko - - 2006
The success rate of in vitro fertilization (IVF) in dogs is low and only early embryos have been obtained. In the present study, we investigated the use of intrauterine transfer of early-stage canine embryos to obtain pups. Twenty-three female dogs, in which the date of ovulation (based on plasma progesterone ...
Turrigiano Gina - - 2006
Many developing networks generate spontaneous network activity (SNA) that plays an important role in setting up functional circuitry, but how the proper level and pattern of SNA is itself maintained has not been clear. In this issue of Neuron, Gonzalez-Islas and Wenner show that SNA in the intact embryo regulates ...
Kominami Tetsuya - - 2006
To gain information on the process of ectoderm patterning, the animal halves of sea urchin embryos were isolated at various stages, and their morphology was examined when control embryos developed into pluteus larvae. The animal halves separated at the 8-cell stage developed into 'dauerblastula', without showing any conspicuous ectoderm differentiation. ...
Liu W M - - 2006
The expression of tetraspanin CD9 was found on blastocysts in mice and endometrium epithelial cells in human and bovine. However, it remains unknown how CD9 is involved in the precise dialogue between embryo and uterus during early pregnancy. This study was designed to investigate the functional roles of CD9 in ...
Kim Ho-Jeong - - 2006
In order to investigate the expression patterns of the transforming growth factor (TGF)beta isoforms in the internal ear, an immunohistochemical study of rat embryos was performed. Rat embryos were taken on the 13th, 15th, 17th, and 19th day after conception and their internal ears were immunohistochemically stained against TGF beta1, ...
Nagase Miki - - 2006
Hedgehog family was reported to be involved in murine yolk sac angiogenesis. However, it has not been clarified whether impaired angiogenesis under hedgehog signaling blockade is attributable to true defect in angiogenic process or just a sequel of earlier vasculogenic abnormalities. In the present study, we examined the effects of ...
Klinger Francesca G - - 2006
Recent studies have demonstrated that the endogenous cannabinoids are important modulators of fertility in mammals. In particular, a role of the endocannabinoid system in early stages of embryo development, oviductal transport of embryos, pregnancy maintenance and labour has been demonstrated in rodents and/or in humans. In the present paper, we ...
Wilson C - - 2006
PURPOSE: To determine the efficacy of using embryos cryopreserved more than ten years in a donor embryo program. METHODS: Embryos were cryopreserved using a simplified freezing protocol and then donated for anonymous use after the donor had had a successful pregnancy and was sure she did not want to conceive ...
Drake Victoria J - - 2006
BACKGROUND: Teratology studies must be carefully designed to minimize potential secondary effects of vehicle and delivery routes. A systematic method to evaluate chick models of early embryogenesis is lacking. METHODS: We investigated 3 experimental approaches that are popular for studies of early avian development, in terms of their utility for ...
King Tim - - 2006
Interest is increasing in assisted reproductive technologies in the pig involving embryo cryopreservation, cloning, and genetic modification. Although inherently inefficient and variable in their outcome, the successful application of these techniques in this species is confounded by unique mechanisms for pregnancy recognition and maintenance that require a minimum number of ...
Michelmann H W - - 2006
Cryopreservation of human embryos from the 2-cell stage up to the morula stage is a safe procedure which has been carried out for the last 25 years. Experience with blastocyst cryopreservation is still limited and pregnancy rates after the use of frozen, thawed blastocysts vary extremely. Vitrification has improved the ...
Tokita Masayoshi - - 2006
The normal embryonic development of the Japanese pipistrelle, Pipistrellus abramus was described. A total of 13 stages between the early pharyngula and the embryo just before birth were established, based on external morphological features of 33 embryonic specimens. To aid embryological comparison between chiropteran lineages, the stage numbers used in ...
Malygin Alexander G - - 2006
A morphodynamic model for phyllotaxis based upon an axiomatic approach is presented. We show that the helical forms of alternate phyllotaxis can be derived from the assumption of the rudiment's growth and movement on the cylindrical embryo surface in the absence of a longitudinal displacement. This leads to the repeating ...
Aston K I - - 2006
This study indicated that prolonged exposure of donor cell nuclei to oocyte cytoplasm before activation results in abnormal chromatin morphology, and reduced development to compacted morula/blastocyst stage in vitro. However, after transfer of embryos to recipients, there was no difference in pregnancy rates throughout gestation. Chromatin morphology was evaluated for ...
Franco M - - 2006
Pregnancy rates following transfer of an in vitro-produced (IVP) embryo are often lower than those obtained following transfer of an embryo produced by superovulation. The purpose of the current pair of experiments was to examine two strategies for increasing pregnancy rates in heat stressed, dairy recipients receiving an IVP embryo. ...
Edgar David H - - 2005
The contribution of cryopreserved embryos to the overall outcomes achieved by a clinical assisted reproduction programme has increased in importance with the trend towards reducing the numbers of fresh embryos transferred following in vitro fertilisation. Although cryopreservation appears to fully preserve developmental potential in early cleavage stage embryos that survive ...
Hershlag Avner - - 2005
Embryos that underwent assisted hatching before freezing had a statistically significant higher survival rate and blastocyst formation rate compared with controls. Therefore, breaching the integrity of the zona pellucida and directly exposing the embryos to cryoprotectants not only does not result in damaging the embryos but might also afford them ...
Farin Peter W - - 2006
In vitro systems for oocyte maturation, fertilization and embryo culture [in vitro production (IVP)] have the potential for more wide-spread use in creative breeding programs for dairy and beef cattle. However, one negative consequence of both IVP and somatic cell nuclear transfer (SCNT) in cattle and other species is that ...
Kattera Suresh - - 2005
OBJECTIVE: To achieve maximum post-thaw survival of frozen embryos. DESIGN: Historical controlled study. SETTING: Hospital-based fertility center. PATIENT(S): One hundred forty-five patients whose embryos were frozen and thawed according to the standard method, and 56 patients whose embryos were frozen and thawed according to a modified method. INTERVENTION(S): Modifications were ...
Silberstein Tali - - 2005
After initiating a policy of ultrasound-guided miduterine cavity embryo transfer (ET) on August 1, 2001, the incidence of retained embryos in the transfer catheter declined significantly from 4.2% (46 of 1,101 ETs) during the time interval January 1, 2000 to July 31, 2001, to 0.7% (6 of 908 ETs) during ...
SuwiƄska Aneta - - 2005
Spontaneous diploid-triploid chimaeras occur sporadically in various mammalian species including man, but so far have never been produced experimentally. In order to get a deeper insight into the developmental consequences of this anomaly, we have developed two procedures that enabled for the first time to produce routinely diploid-triploid embryos, foetuses, ...
Blank Danilo - - 2005
OBJECTIVE: To evaluate the impact of SciELO and MEDLINE indexing on the number of articles submitted to Jornal de Pediatria. METHODS: Analysis of total article submission, submission of articles from foreign countries and acceptance figures in the following periods: stage I - pre-website (Jan 2000-Mar 2001); stage II - website ...
Kuwayama Masashige - - 2005
Survival and development of human embryos was compared following slow cooling versus vitrification involving more than 13,000 vitrified embryos. In addition, the efficacy of an open system, the Cryotop, and a closed vitrification system, the CryoTip(trade mark), were compared using human blastocysts. One hundred percent of vitrified human pronuclear stage ...
Boettcher Paul J - - 2005
The objective of this empirical simulation study was to evaluate the use of a combination of semen and embryos in the creation of gene banks for reconstruction of an extinct breed. Such an approach was compared for banks with varying proportions of embryos on the basis of the amount of ...
Lopes A S - - 2005
Oxygen consumption is a useful parameter for evaluating embryo quality, since it provides a valuable indication of overall metabolic activity. Over the years, several approaches have been used to measure the respiration rates of individual embryos, but a convincing method has not yet been reported. In this study, we introduce ...
Orihuela Pedro A - - 2006
AIM: We examined whether the aqueous extract of Erythrina falcata, reputed to be a contraceptive in Peruvian folklore, could prevent pregnancy in the mouse. METHODS: Female mice on Day 1 of pregnancy were given aqueous extract of E. falcata or tap water (control) orally for 4 days. On Day 4 ...
Satoh Nori - - 2005
This year is the centenary of Edward G. Conklin's signal findings in embryology: the elucidation of complete cell lineages and the discovery of localized maternal determinants. Conklin used ascidian embryos to elucidate universal principles in embryology. A century later, ascidians, or sea squirts, have not only entered the post-genome era, ...
Dixon James C - - 2005
INTRODUCTION: Perinatal brain injury is more common in growth-restricted (GR) than normally grown (NG) fetuses. This study addresses the hypothesis that chronic oxygen and substrate deprivation during pregnancy will engender an abnormal fetal cerebral metabolic response to acute hypoxia. METHOD: Cerebral metabolite resonance amplitudes relative to that of creatine were ...
Bényei Balázs - - 2006
The objectives of this work were to determine the effect of external (synchronization methods, month, embryo origin and farm effects) and internal factors (age and size of CL, embryo development and quality score, synchronization methods, age of recipient, quality of transfer and reuse of recipients) on a commercial embryo transfer ...
Rienzi Laura - - 2005
OBJECTIVE: Partially damaged frozen and thawed embryos are currently considered to have a lower viability than intact ones. This study was undertaken to compare the performance of intact frozen and thawed embryos with that of partially damaged embryos after removal of the necrotic blastomeres. DESIGN: Observational clinical series. SETTING: Private ...
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