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51.
Wojciech Witarski Barbara Kij Agnieszka Nowak Monika Bugno-Poniewierska 《Reproduction in domestic animals》2020,55(2):248-251
A hucul mare with reproductive abnormalities was examined during karyotype analysis. The karyotype was analysed based on evaluation of 860 metaphase plates in chromosome preparations. The use of fluorescence in situ hybridization (FISH) with an X chromosome painting probe showed premature X chromosome separation in 9.5% cases of examined chromosome spreads. In this report, we present the first identify premature centromere division (PCD) as a possible cause of abnormal X chromosome morphology in horses and as a probable cause of reproductive difficulties. 相似文献
52.
Nowak R 《Science (New York, N.Y.)》1995,267(5205):1761-1762
53.
To probe variation in Al sensitivity of two co-occurring pine species, seedlings from six full-sib families of loblolly pine (Pinus taeda L.) and slash pine (Pinus elliottii Engelm.) were grown in solution culture containing 4.4 mM (high-Al) or 0.01 mM (low-Al) AlCl(3) at pH 4 for 58 days. On average, both pine species had 41% less total dry weight in the high-Al treatment than in the low-Al treatment. Stem volume growth of slash pine was more sensitive to the high-Al treatment than that of loblolly pine. In both species, the high-Al treatment inhibited root dry weight more than shoot dry weight. Within-species variation in Al sensitivity among families was greater in loblolly pine (24 to 52% inhibition of seedling dry weight) than in slash pine (35 to 47% inhibition of seedling dry weight). Foliar Al concentration was positively correlated with Al sensitivity in slash pine but not in loblolly pine; however, in both species, the concentration of Al in roots was 20-fold greater than in foliage. 相似文献
54.
Nowak RM 《Science (New York, N.Y.)》1991,253(5017):250-251
55.
Obtaining Wisent early blastocyst in vitro is a basic for protection and creation of biodiversity for this threatened species 下载免费PDF全文
AM Duszewska P Gręda M Baraniewicz W Bielecki W Niżański A Partyka M Tracz Z Nowak A Chełmońska‐Soyta W Olech 《Reproduction in domestic animals》2018,53(3):818-821
Wisent, or European bison (Bison bonasus), is listed as “vulnerable” on the IUCN Red List of Threatened Species and is therefore protected by international law. For the first time, a Wisent embryo has been obtained in vitro. This procedure creates a new opportunity to protect and increase Wisent reproductive potential and thereby opens new possibilities for the establishment of a controlled and broad reserve of the gene pool. 相似文献
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We determined how ecophysiological characteristics of two juniper species, Juniperus occidentalis Hook. (western juniper) and Juniperus osteosperma (Torr.) Little (Utah juniper), changed along altitudinal and regional environmental gradients in the Great Basin of western North America. We obtained diurnal measurements of leaf gas exchange and xylem water potential (Psi) from plants at a low and a high altitude site within each of six mountain ranges during fall 1994, spring, summer, and fall 1995, and summer 1996. We also determined carbon isotope composition (delta(13)C) of leaf cellulose produced during the 1995 growing season. Overall, leaf gas exchange, Psi and delta(13)C did not differ significantly between species. Differences in daily (A(d)) and season-long (A(s)) carbon assimilation among mountain ranges suggested two groupings-a group of northern ranges and a group of southern ranges. Each group contained one mountain range with J. occidentalis and two with J. osteosperma. Differences in carbon assimilation based on this grouping were associated with two findings: (1) conductance of CO(2) from substomatal cavities to the site of carboxylation (g(m)) for junipers in the northern ranges averaged almost twice that of junipers in the southern ranges; and (2) physiological shifts occurred such that A(d) of junipers in the northern ranges was influenced more by Psi(pd), whereas A(d) of junipers in the southern ranges was influenced more by leaf temperature. Mean delta(13)C over all trees at a site was significantly correlated with annual precipitation. Significant differences in A(d) occurred between altitudes, but these differences were associated with differences in the timing of optimum leaf temperature for photosynthesis rather than with physiological acclimation to temperature, irradiance, or Psi. Most gas exchange parameters (e.g., assimilation, transpiration, stomatal conductance, and water use efficiency) varied seasonally, and the seasonal differences were strongly influenced by water stress. 相似文献
59.
In response to concerns about aluminum and HCl exposure associated with rocket motor testing and launches, survival and growth of full-sib families of loblolly pine (Pinus taeda L.) and slash pine (Pinus elliottii Engelm.) were evaluated in a nursery bed experiment. Each species was exposed to a single soil application of aluminum chloride (0.33 M AlCl(3), pH 2.5), hydrochloric acid (0.39 M HCl, pH 0.6) or water, with or without mycorrhizal inoculation with Pisolithus tinctorius (Coker and Couch). After 20 weeks without inoculation, survival in AlCl(3) and HCl treatments averaged 52% for loblolly pine and 72% for slash pine. Inoculation improved survival of loblolly pine, receiving HCl from 49 to 73%, and of those receiving AlCl3, from 55 to 90%. Inoculation also resulted in improved survival and growth of individual families in AlCl(3), but not in HCl treatments. Results illustrate the relative resistance of both pine species to the acute treatments supplied, the improvement in resistance associated with mycorrhizal inoculation and the importance of field testing, following hydroponic screening, to verify the resistance to soil-supplied stresses. 相似文献
60.
Morrison RN Koppang EO Hordvik I Nowak BF 《Veterinary immunology and immunopathology》2006,109(3-4):297-303
Amoebic gill disease (AGD) is characterised by the association of Neoparamoeba sp. with hyperplastic gill tissue of affected fishes, however, the identity and role of host cells associated with AGD lesions are not known. Here, we investigated cells with an immunological role that were associated with AGD lesions by locating cellular MHC class II β chain. A tank housing Atlantic salmon (Salmo salar) was inoculated with Neoparamoeba sp., and MHC class II β chain expression in the gills was qualitatively assessed by immunohistochemistry. In AGD-naïve control fish, MHC class II+ cells were detected basolateral to the interlamellar epithelium as well as upon the interlamellar and secondary epithelium. In the gills of AGD affected fish MHC class II+ cells were observed in both affected and unaffected tissue. Within AGD lesions, numerous MHC class II+ cells were present and these cells exhibited variable levels of expression suggesting that like mammals, MHC class II expression is highly regulated. The presence of MHC class II+ cells within gill lesions is indicative of immune cell trafficking and these cells could contribute in an antigen presentation capacity to the development of an antibody response in fish chronically affected by AGD. 相似文献