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41.
A three‐dimensional alginate system for in vitro culture of cumulus‐denuded feline oocytes 下载免费PDF全文
In the case of high valuable individuals with very precious genetic material, widening the genetic pool including gametes with poor morphological characteristics, as cumulus‐denuded oocytes (CDOs), could be an option. To improve the in vitro culture of low‐competence feline CDOs, an enriched three‐dimensional (3D) system in association with competent cumulus–oocyte complexes (COCs) was developed. For this purpose, domestic cat CDOs were cultured with or without companion COCs in the 3D barium alginate microcapsules. The overall viability and the meiotic progression of feline CDOs cocultured with COCs or cultured separately in 3D or in 2D (traditional microdrops) system were compared. The 3D system was able to support viability and meiotic resumption of the feline oocytes, as well as the 2D microdrops. In 3D microcapsules, the presence of COCs resulted in a higher viability of CDOs (91.1%, p < .05), than that obtained without COCs or in 2D microdrops (71.2% and 67.3%, respectively), but the percentages of meiotic resumption were similar of those of CDOs cultured separately (55.4% vs. 40.4%, p > .05). It is notable that the presence of CDOs seemed to enhance the meiotic progression of the associated COCs. In conclusion, the 3D barium alginate microcapsules are a suitable system for feline oocytes in vitro culture, but more specific enriched conditions should be developed to improve the CDOs full competence in vitro. 相似文献
42.
Dini I Tenore GC Schettino O Dini A 《Journal of agricultural and food chemistry》2001,49(8):3976-3981
Six triterpenoid saponins were isolated from the seeds of Chenopodium quinoa (Chenopodiaceae). Their structures were as follows: phytolaccagenic acid 3-O-[alpha-L-arabinopyranosyl-(1' '-->3')-beta-D-glucuronopyranosyl]-28-O-beta-D-glucopyranoside (1); spergulagenic acid 3-O-[beta-D-glucopyranosyl-(1-->2)-beta-D-glucopyranosyl-(1-->3)-alpha-L-arabinopyranosyl-28-O-beta-D-glucopyranoside (2); hederagenin 3-O-[beta-D-glucopyranosyl-(1-->3)-alpha-L-arabinopyranosyl]-28-O-beta-D-glucopyranoside (3); phytolaccagenic acid 3-O-[beta-D-glucopyranosyl-(1-->4)-beta-D-glucopyranosyl-(1-->4)-beta-D-glucopyranosyl]-28-O-beta-D-glucopyranoside (4); hederagenin 3-O-[beta-D-glucopyranosyl-(1-->4)-beta-D-glucopyranosyl-(1-->4)-beta-D-glucopyranosyl]-28-O-beta-D-glucopyranoside (5); and spergulagenic acid 3-O-[alpha-L-arabinopyranosyl-(1' '-->3')-beta-D-glucuronopyranosyl]-28-O-beta-D-glucopyranoside (6). Saponins 5 and 6 are new. The structures were characterized on the basis of hydrolysis and spectral evidence, including IR, UV, optical rotations, 1D- and 2D-NMR (HMQC and HMBC), ESIMS, and FABMS analyses. 相似文献
43.
Congenital Abnormality of the Vagina Complicated by Haemato‐Pyocolpos in a 1‐Year Labrador Retriever 下载免费PDF全文
A 1‐year‐old female Labrador retriever was referred with a few days history of haematic‐like vulvar discharge. Physical examination, vaginal inspection and palpation did not reveal any remarkable finding. Transabdominal ultrasound showed echogenic fluid accumulation in the vagina suggesting haemato‐pyocolpos. An exploratory laparotomy was performed: a well‐delimited ectasic vagina was identified. Ovariohysterectomy and partial vaginectomy and vaginoplasty were performed to spay the bitch and to remove the ectasic vagina. Post‐operative recovery and 12‐month follow‐up were uneventful. Clinical, morphological and histological findings were consistent with a congenital abnormality of the muscular layer of the vagina complicated by haemato‐pyocolpos. The disorganization of the vaginal tunica muscularis may have acted as locus minoris resistentiae in the vaginal wall. The organ was dilated and atonic due to the gradual accumulation of physiological fluids complicated by an overgrowth of genital bacteria. This congenital disorder has to be taken into account as differential diagnosis of haemato‐pyocolpos with vaginal discharge in young bitches. 相似文献
44.
Mario RO Barsottini Brbara A Pires Maria L Vieira Jos GC Pereira Paulo CS Costa Jaqueline Sanit Alessandro Coradini Fellipe Mello Cidnei Marschalk Eder M Silva Daniele Paschoal Antonio Figueira Fbio HS Rodrigues Artur T Cordeiro Paulo CML Miranda Paulo SL Oliveira Maurício L Sfora Marcelo F Carazzolle Silvana A Rocco Gonalo AG Pereira 《Pest management science》2019,75(5):1295-1303
45.
Detritivores have been thought to derive nutrition from microbes associated with detrital particles and not from the nonliving plant substrate. The polychaete Capitella capitata, however, was found to derive a major portion of its nitrogen from the plant substrate when it feeds on detritus derived from seaweed. Microbes play a role as a nitrogen source for this detritivore when it feeds on detritus derived from marsh grass. 相似文献
46.
HM Knijn W Fokker GC van der Weijden SJ Dieleman PLAM Vos 《Reproduction in domestic animals》2012,47(2):177-183
The objective of this study was to evaluate a new superovulation procedure with oFSH after temporary suppression of the endogenous LH surge by norgestomet followed by administration of GnRH, to collect bovine oocytes and embryos at specific developmental stages. Since 1999, our research group applies this superovulation procedure with controlled release of the endogenous LH surge. The objective of this study is to verify if this procedure is reliable for collection of oocytes and embryos at specific time points of development and if it produces a sufficient number of both oocytes and embryos of good quality. This procedure was validated regarding to hormonal characteristics, superovulatory response and both oocyte and embryo yield at different times of in vivo development. The results demonstrate that the procedure used to control the occurrence of the pre‐ovulatory LH surge was effective in 92% of the animals (n = 238) and even in 99% of the animals the oocytes and embryos were collected at the intended stage of development. The superovulatory response and both oocyte, embryo yield and quality were similar to the average yield in Europe reported by Association Européenne de transfert embryonnaire (AETE). In conclusion, this superovulation procedure provides a valid tool to collect oocytes and embryos at specific time points of development. 相似文献
47.
48.
Mongolian Tree Rings and 20th-Century Warming 总被引:3,自引:0,他引:3
A 450-year tree-ring width chronology of Siberian pine (Pinus sibirica Du Tour) growing at timberline (2450 meters) in the Tarvagatay Mountains in west central Mongolia shows wide annual growth rings for the recent century. Ecological site observations and comparisons with instrumental temperature records indicate that the ring widths of these trees are sensitive to annual temperature variations. Low-frequency variations in the Tarvagatay tree-ring record are similar to those in a reconstruction of Arctic annual temperatures, which is based on 20 tree-ring width series from northern North America, Scandinavia, and western Russia. The results indicate that recent warming is unusual relative to temperatures of the past 450 years. 相似文献
49.
50.
The aim of this study was to investigate the effects of culture in isolated oviducts relative to meiotic maturation, the time required to resume meiosis and the viability of the canine oocytes. For this purpose, cumulus–oocyte complexes and isthmus–ampullar tracts of the oviducts were collected from bitches undergoing ovariohysterectomies and destined to two experiments of culture. In experiment 1, the oocytes were cultured for 24 or 30 h: (1) in 100 μl drops under oil; (2) on the mucosal epithelium of the open oviducts; (3) in the ligated oviducts. In experiment 2, oocytes were cultured in the ligated oviduct for 24, 30 and 48 h. A group of control oocytes was not cultured (0 h). The results showed that within 30 h of culture, a higher proportion of oocytes (p < 0.001) resumed meiosis in the ligated oviduct (63.8%) than in drop (20.4%) or in the open oviduct (27.1%). Moreover, 24 and 30 h of culture assured higher proportions of meiosis resumption than 48 h (69.2 and 59.1% vs 35.8%, p < 0.005). Oocyte resumption of meiosis was mainly determined by oocytes at meiotic stages preceding metaphase I, while stages between metaphase I and II in the ligated oviduct ranged between 12.5 and 31.9%. The extension of the culture time up to 48 h in the oviduct increased oocyte degeneration significantly (59.3%, p < 0.0001) compared with 24 and 30 h (18.7 and 27.3%, respectively) and the oviductal epithelium showed nuclear picnosis and degeneration following culture. The present study suggests that the close physical interaction between the canine oocytes and the oviductal tract positively affects oocyte maturation, and meiosis is resumed within 30 h of culture. Moreover, the oocyte survival is better preserved within 30 h in the ligated oviduct compared with the conventional culture in drop or to the culture in the open oviduct, but the ligated oviduct does not assure viability of the oocytes up to 48 h of culture. 相似文献