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1.
Polymers (Basel) ; 15(3)2023 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-36771993

RESUMO

The manufacturing of paper with new functional properties is a current problem today. A method of modifying the surface layer of paper by the partial dissolution of cellulose on its surface is proposed. N-Methylmorpholine-N-oxide (NMMO) is proposed for use as a solvent, the regeneration of which provides an environmentally friendly process. It was shown that among the possible hydrate forms of the solvent, the monohydrate and higher-melting forms are optimal for modifying the paper surface. The temperature-time modes of processing were revealed and the weight gain and density increase in the course of modification were estimated. The structural and morphological features of the original and modified paper were studied by X-ray imaging and scanning microscopy. The NMMO surface treatment makes it possible to vary the air permeability of the paper, making it practically non-permeable. The capillary and pore system were radically transformed after the partial dissolution of cellulose and its coagulation, as the formed cellulose film isolates them, which leads to a decrease in surface absorbency. The processing conditions allowing for the optimization of the optical and strength properties of the modified paper samples are revealed. The resulting paper with a modified N-methylmorpholine-N-oxide surface layer can be used for printing valuable documents.

2.
Genes (Basel) ; 12(1)2020 12 25.
Artigo em Inglês | MEDLINE | ID: mdl-33375549

RESUMO

We studied the impact of age and the serum anti-Müllerian hormone (AMH)/follicle-stimulating hormone (FSH) levels on the number of cumulus-oocyte complexes (COCs) retrieved from female reciprocal and Robertsonian translocation carriers after controlled ovarian hyperstimulation (COH). The number of COCs retrieved after COH was retrospectively analyzed in female translocation carriers and 46,XX partners of male translocation carriers from 100 couples. The median number of COCs varied from nine to 16 and did not differ among subgroups of women categorized by age, presence and type of a translocation. The number of COCs correlated negatively with the woman's age in both the reciprocal and the Robertsonian translocation carriers, while in 46,XX women no correlation was detected. The number of COCs did not differ between the reciprocal and the Robertsonian translocation carriers aged either <35 or ≥35 years. In translocation carriers, the number of COCs correlated with the serum AMH level only in the younger-age subgroups; the correlation was strong positive in reciprocal and moderate positive in Robertsonian translocation carriers. The 46,XX women aged both <35 and ≥35 years showed similar moderate positive correlations. Across all subgroups, the number of COCs correlated moderately negatively with the serum FSH level only in Robertsonian translocation carriers aged <35 years. Our results suggest that chromosomal translocations per se do not increase the risk of poor oocyte retrieval outcome after COH. In translocation carriers, oocyte retrieval outcome depends to a large extent on their age. The serum AMH level strongly predicts oocyte retrieval outcomes only in young reciprocal translocation carriers, while the serum FSH level has a moderate predictive value in young Robertsonian translocation carriers.


Assuntos
Hormônio Antimülleriano/sangue , Hormônio Foliculoestimulante/sangue , Infertilidade Feminina/terapia , Recuperação de Oócitos/estatística & dados numéricos , Translocação Genética , Adulto , Fatores Etários , Feminino , Heterozigoto , Humanos , Infertilidade Feminina/sangue , Indução da Ovulação/estatística & dados numéricos , Estudos Retrospectivos , Resultado do Tratamento
3.
Gynecol Endocrinol ; 33(9): 737-740, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28617148

RESUMO

It is well documented that aneuploidy rate in preimplantation embryos increases with the mother's age, and at the same time the number of oocytes diminishes. Consequently, for patients of advanced maternal age two options are available to overcome these limitations: use of oocytes from young donors, or use of own oocytes coupled with preimplantation genetic screening (PGS) for 24 chromosomes. However, it is not clear which strategy might be more effective. The aim of this retrospective study was to evaluate outcomes of IVF cycles coupled with transfer of vitrified embryos from donor or autologous oocytes, both with or without PGS. Our results demonstrate that while after PGS clinical pregnancy, twin pregnancy and spontaneous abortion rates are similar for embryos from donor and autologous oocytes, these rates are dramatically worse in all cycles without PGS. Therefore, PGS can be recommended as a screening method to all patients of advanced maternal age even when donor oocytes are used.


Assuntos
Hibridização Genômica Comparativa/métodos , Transferência Embrionária , Fertilização in vitro/métodos , Resultado da Gravidez , Diagnóstico Pré-Implantação/métodos , Adulto , Fatores Etários , Implantação do Embrião , Feminino , Humanos , Idade Materna , Doação de Oócitos , Gravidez , Estudos Retrospectivos , Vitrificação
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