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81.
Follicle-like structures are three-dimensional matrices joint with living cells that allow the in vitro development of female gametes in more physiological conditions. They have been shown to be beneficial to fresh oocytes in different species, and in this study, domestic cat (Felis silvestris catus) granulosa cells were used to create a functional follicle-like structure aimed at supporting the in vitro maturation of conspecific vitrified oocytes, key players of fertility preservation programmes that usually struggle to acquire their full developmental competence after warming. Cat granulosa cells were cultured for up to 6 days in three-dimensional barium alginate microcapsules (i.e. follicle-like structures) or in two-dimensional monolayers, and their steroidogenic ability (estradiol and progesterone secretion) was assessed to confirm their functionality. The same systems were used (on day 2 or 6 of granulosa cells culture) for the in vitro maturation (IVM) of Cryotop® vitrified immature cat oocytes and compared with microdrops of IVM medium without cells (control). Granulosa cells were able to maintain their functionality in vitro in both the conditions, even if with a different extent of hormonal secretion along culture (p = .02). Vitrified oocytes resumed meiosis at higher rates when cultured with 2 days old granulosa cells (p = .03), but full maturation rates slightly raised when granulosa cells were cultured longer, albeit without differences with the control group. This study paved the road for the creation of enriched culture systems in the domestic cat, but innovations are strongly needed for vitrified oocytes that deserve better chances to develop in vitro.  相似文献   
82.
The Pennask Creek watershed in British Columbia (BC), Canada has been contaminated with acid rock drainage (ARD) and associated metal leaching (ML) as a result of highway construction. By combining existing and newly gathered information, this study determined the extent of metal contamination of the water and sediments, the potential biological impacts of this contamination, the influence of local geology, and estimated the potential risk to aquatic organisms. Surface water and sediment samples from the watershed were analyzed for general chemical parameters and trace metals. Rock samples were analyzed for mineralogy and chemical composition. Metal concentrations in water and sediments downstream of the ARD/ML source were higher than elsewhere in the watershed. Metals of concern include aluminum (Al), copper (Cu), and zinc (Zn). Analysis of historical water quality data indicated that the concentrations of these metals have decreased markedly since 2004, due to remediation efforts. Rock samples collected from the streambeds and banks were not found to be potentially acid generating, but did contain significant levels of metals. Al, Cu, and Zn levels consistently exceeded BC water and sediment quality guidelines for the protection of aquatic life, indicating that adverse biological effects are probable at stations downstream of the ARD/ML source. Benthic invertebrate monitoring over a 10-year period showed low abundance and diversity and a complete absence of sensitive taxa at downstream stations. Risk quotients indicated a likelihood of adverse biological effects for aquatic organisms, including rainbow trout, due to metal contamination in the watershed.  相似文献   
83.
A long catheter was inserted into the superior sagittal sinus of sheep and was maneuvered to the level of the rectus sinus. The catheter was then secured to the head, neck, and shoulder of the animal. The distal end of the catheter was connected to a 3-way valve through which blood samples were collected and heparin was injected. Blood loss during surgery was minimal; recovery was quick and complete. The simple surgical technique enabled the collection of blood that has just perfused the pineal gland.  相似文献   
84.
Several physicochemical tests are employed in quality evaluation of wheat. Most of the exported Argentinean wheat flour is used as corrector flour in breadmaking. A small percentage is actually used in cookie production. No study has determined which predictive tests are most suitable for the quality prediction of bread (using flour as corrector) and cookies made from Argentinean wheat. The objectives of this study were to compare the suitability of predictive tests in the assessment of wheat flour attributes in the production of bread and cookies and to establish the relationship between the tests and flour components. Several expected associations were found between the SRC test and the composition parameters. Moreover, various flour components influencing the SDS sedimentation index (SDS-SI), the Zeleny index and the alkaline water retention capacity (AWRC) were established. The cookie factor (CF) was negatively correlated with sucrose, carbonate and water SRC and with AWRC. In addition, the bread loaf specific volume (LV) was correlated with the SDS-SI, the Zeleny index and the lactic acid SRC. In conclusion, several components of Argentine wheat affecting predictive tests were found. The SRC test allowed straight assessment of the bread and cookie quality of Argentinean wheat.  相似文献   
85.
A 13-year-old, thoroughbred mare was presented with an 8-year history of multifocal, generalized, noninflammatory alopecia and a 3-month history of alopecia, erythema and scaling of the white star on the forehead and muzzle. Histopathological examination of biopsy samples from multiple sites on the body (mane, neck, shoulder, flank and gluteal region) showed a subtle lymphocytic inflammatory infiltrate affecting and surrounding the anagen hair bulbs, consistent with a diagnosis of alopecia areata. The biopsy sample from the star on the forehead showed atrophic hair follicles with perifollicular and mural mononuclear folliculitis affecting the isthmus. Immunohistochemical staining with a CD3 marker confirmed the T-lymphocytic origin of the inflammatory infiltrate in all the samples. The concurrent presence of lymphocytic infiltration at the bulbar and isthmic level of the hair follicles in the same horse is unusual. This finding may represent a variation of the histological appearance of alopecia areata.  相似文献   
86.
The possible role of some acute phase proteins (APPs) and immunoglobulins in both the pathogenesis and diagnosis of feline infectious peritonitis (FIP) has been investigated. Serum protein electrophoresis and the concentration of haptoglobin (Hp), serum amyloid A (SAA), alpha(1)-acid glycoprotein (AGP), IgG and IgM were evaluated in cats exposed to feline coronavirus (FCoV) and in cats with FIP. The highest concentration of APPs was detected in affected cats, confirming the role of these proteins in supporting a clinical diagnosis of FIP. Repeated samplings from both FIP affected and FCoV-exposed cats showed that when FIP appeared in the group, all the cats had increased APP levels. This increase persisted only in cats that developed FIP (in spite of a decrease in alpha(2)-globulins) but it was only transient in FCoV-exposed cats, in which a long lasting increase in alpha(2)-globulins was observed. These results suggest that changes in the electrophoretic motility of APPs or APPs other than Hp, SAA and AGP might be involved in the pathogenesis of FIP or in protecting cats from the disease.  相似文献   
87.
A common bean genomic library was constructed using the ‘IAC-UNA’ variety enriched for (CT) and (GT) for microsatellite motifs. From 1,209 sequenced clones, 714 showed microsatellites distributed over 471 simple and 243 compound motifs. GA/CT and GT/CA were the most frequent motifs found among these sequences. A total of 123 microsatellites has been characterized. Out of these, 87 were polymorphic (73.7%), 33 monomorphic (26.8%), and 3 (2.4%) did not amplify at all. In a sample of 20 common bean materials selected from the Agronomic Institute Germplasm Bank, the number of alleles per locus varied 2–9, with an average of 2.82. The polymorphic information content (PIC) of each marker varied from 0.05 to 0.83, with a 0.45 average value. Cluster and principal coordinate analysis of the microsatellite data were consistent with the original assignment of the germplasm accessions into the Andean and Mesoamerican gene pools of common bean. Low polymorphism levels detected could be associated with the domestication process. These microsatellites could be a valuable resource for the bean community because of their use as new markers for genetic studies. Electronic supplementary material The online version of this article (doi: ) contains supplementary material, which is available to authorized users. An erratum to this article can be found at  相似文献   
88.
Phosphate sorption and desorption in soils are markedly influenced by iron oxides, although little is known on how the common iron oxides differ in their behaviour towards added phosphate. In this study, we investigated phosphate sorption and desorption in the clay fractions of 12 Terre Rosse that ranged widely in Fe oxide content, had very low contents of oxalate-extractable Fe oxides and different hematite/goethite ratios. Phosphate sorption at an equilibrium concentration of 1 mg P 1?1 was correlated with the goethite but not with the hematite content of the clay fractions. When phosphate was desorbed by electro-ultrafiltration, the difference in desorption half-time between untreated and deferrified clays was positively correlated with the goethite but not with the hematite content. These results suggest that goethite is more active than hematite in phosphate sorption and retention by soils.  相似文献   
89.
90.
Eastern larch (Larix laricina [du Roi] K. Koch) container seedlings were tested to determine shoot frost hardiness development under short or long days and warm (15 to 25 °C) or cool (10/5 °C, day/night) temperatures, to aid in the development of greenhouse hardening strategies. Seedlings were sampled sequentially over time (25 seedlings per week) from a population of 1000 trees. Frost hardiness increased significantly after one week of fluctuated over the next 6 weeks, and increased thereafter through week 14. Seven weeks of warm, intermittent short days, followed by 6 weeks of cool, continuous short days, resulted in greater frost hardiness than 13 weeks of warm, intermittent short days. In contrast, seedlings exposed to 7 weeks of warm, intermittent short days, followed by six weeks of warm, long days were significantly less frost hardy. Stems with needles attached had lower Index of Injury than stems without needles.  相似文献   
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