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101.
Eva-Maria Halbauer Valentina Bohinec Melanie Wittenberger Karin Hansel-Hohl Stephan Gaubitzer Eva M. Sehr 《Euphytica》2017,213(6):120
Agro-biodiversity is currently experiencing severe genetic erosion due to mankind’s unsustainable activities. Because of initiatives following the goal of the conservation of biological diversity, so far seven million crop accessions are being conserved ex situ in gene banks worldwide. Many of these accessions are landraces being rich in gene diversity, silently awaiting their proper characterisation. This is a very critical part of any long-term strategy to enhance the productivity and resilience of crops and agricultural systems and—most importantly—to ensure the preservation of our cultural and biological heritage. In this study of an ex situ germplasm evaluation we analysed 27 flax (Linum usitatissimum L.) accessions originating in the Alpine region, provided by five local gene banks/providers. Based on genomic microsatellite markers (gSSRs), a varying extent of accession-specific gene diversity (expected heterozygosity, HE) was revealed ranging from 0.05 to 0.51. Admixture of individuals between accessions was uncovered, pointing towards past processes related to gene bank management activities (e.g. intentional selection, unintentional cross-pollination during regeneration) or towards the evolution of the landrace itself (e.g. same regional origin, traditional naming), highlighting the co-existence of cultural and biological diversity. Such an genetic analysis of accessions stored ex situ not only produces valuable agronomic and breeding data, but also is useful for the clarification of past processes leading to duplicates within and between collections or mislabelling, contributing to the potential for rationalisation of collections, which in turn can help ensure that the limited resources available for regeneration are used most efficiently and effectively. 相似文献
102.
导入LPAAT和KCS基因对油菜种子芥酸含量的影响 总被引:4,自引:0,他引:4
采用农杆菌介导法,以下胚轴为转化受体,将溶血性磷脂酸酰基转移酶(LPAAT)和酮脂酰辅酶A合成酶(KCS)基因导入2种不同基因型(“Drakkar”和“Maplus”)的甘蓝型油菜,共获得247株再生植株,其再生频率分别为15.1%和2.0%。PCR检测和Southern杂交分析证实,外源基因已整合到油菜基因组中,转化频率分别为3.6%和0.7%。种子中芥酸含量因外源基因的导入使零芥酸油菜“Drakkar”提高到10.5%,高芥酸品种“Maplus”提高了5.0%,最高达62.8%。 相似文献
103.
Sun Haijun Zhang Hailin Xiao Hongdong Shi Weiming Müller Karin Van Zwieten Lukas Wang Hailong 《Journal of Soils and Sediments》2019,19(4):1624-1631
Journal of Soils and Sediments - The potential for using biochar to reclaim degraded urban land into productive land needs to be verified to address the incipient loss of agricultural land. A pot... 相似文献
104.
OBJECTIVE: To study associations between reported sugar intake and salivary bacteria (mutans streptococci, MS and lactobacilli, LB), and sugar intake in relation to body mass index (BMI), in women and adolescents. DESIGN: Cross-sectional study. Habitual dietary intake was reported in a questionnaire and whole saliva samples were collected and cultivated. SETTING: Stockholm, Sweden. SUBJECTS: Four hundred and fourteen mothers and their 16-year-old children (57% girls). RESULTS: Reported total sugar intake was significantly associated with LB in mothers (P = 0.001), but not in daughters and sons (P = 0.03 for mother-son interaction). When excluding lactose, the associations with LB and MS were significant in daughters (P = 0.032 and 0.005, respectively). High BMI and sugar intake from milk were independently associated with MS counts in mothers in a multiple regression model (R2 = 0.053). In daughters, sugar from beverages, candies/chocolates and fruits were all independently associated with MS counts (R2 = 0.074), whereas in sons, only mothers' MS counts were associated (R2 = 0.084). High BMI, low intake from cooked meals and high intake of candies/chocolates were all independently associated with LB in mothers (R2 = 0.076), while, except for candies/chocolates in daughters, no significant associations were found in children. BMI was significantly associated with bacteria counts in both mothers and children, whereas reported sugar intake was not. CONCLUSION: The associations between reported sugar intake and bacteria were generally weak. In mothers and daughters, some significant associations were found, but not in sons. Bacteria counts, but not reported sugar intake, were positively associated with BMI. 相似文献
105.
Within an extensive study on endangered biotopes in the State of Saxony-Anhalt/Eastern Germany, the millipede fauna of 50 dry habitats, belonging to 5 types of biotopes was studied from 1995 to 1998 using pitfall traps. The most abundant species were Glomeris marginata and Cylindroiulus caeruleocinctus. By applying a combination of the criteria repraesentanz, constancy and dominance a new criterion, the “common-habitat-relation”, has been introduced to establish biotope-characteristic species and communities of millipedes. The results show that by using these criteria together, distinct groups can be formed consisting of “characteristic” and “companion species”. Eleven out of 34 species that occurred on the sites fitted into this grouping. Characteristic species groups were determined for mesoxeric meadows (C. caeruleocinctus, G. marginata and Glomeris hexasticha) and “succession” sites (Allaiulus nitidus and Polydesmus angustus). The sandy dry meadows were characterized by companion species only (Megaphyllum unilineatum and Ommatoiulus sabulosus), the heavy-metal grassland by the characteristic species Craspedosoma rawlinsii without companion species. For dwarf-shrub heaths no typical species groups could be found. 相似文献
106.
107.
Naugler WE Sakurai T Kim S Maeda S Kim K Elsharkawy AM Karin M 《Science (New York, N.Y.)》2007,317(5834):121-124
Hepatocellular carcinoma (HCC), the most common liver cancer, occurs mainly in men. Similar gender disparity is seen in mice given a chemical carcinogen, diethylnitrosamine (DEN). DEN administration caused greater increases in serum interleukin-6 (IL-6) concentration in males than it did in females. Furthermore, ablation of IL-6 abolished the gender differences in hepatocarcinogenesis in mice. DEN exposure promoted production of IL-6 in Kupffer cells (KCs) in a manner dependent on the Toll-like receptor adaptor protein MyD88, ablation of which also protected male mice from DEN-induced hepatocarcinogenesis. Estrogen inhibited secretion of IL-6 from KCs exposed to necrotic hepatocytes and reduced circulating concentrations of IL-6 in DEN-treated male mice. We propose that estrogen-mediated inhibition of IL-6 production by KCs reduces liver cancer risk in females, and these findings may be used to prevent HCC in males. 相似文献
108.
109.
Karin Müller Susanne Eder Ulrike Jakop Jürgen Schiller Peter Müller Mohammad Bashawat 《Reproduction in domestic animals》2020,55(Z2):55-60
Cryobanking of gametes in combination with artificial insemination is an essential option to support conservation programmes for endangered and threatened species. About two-thirds of the felid species are classified as ‘near threatened’, ‘vulnerable’ or ‘endangered’ ( www.cites.org ), and mostly, epididymal sperm are collected from euthanized or castrated male felids and cryopreserved. However, epididymal compared with ejaculated and cryopreserved compared with fresh sperm have a limited potential to fertilize if vaginal non-surgical insemination is applied in feline species. Missing or highly diluted seminal fluid in epididymal and cryopreserved sperm, as well as a potential interference of extender ingredients with the natural interactive properties of sperm in the female genital tract is discussed as potential drawback which hampers a proper sperm transit and fertilization besides the limited longevity of cryopreserved feline sperm. Individual components in seminal fluid as well as cryoextenders may adversely alter sperm properties and have a different impact on fertility and preservation success. The identification and investigation of beneficial as well as detrimental components is a precondition to deduce options for improving the process of cryopreservation in felids, particularly, if only epididymal sperm are available. 相似文献
110.
Control of experimental autoimmune encephalomyelitis by T cells responding to activated T cells 总被引:21,自引:0,他引:21
T cell vaccination against experimental autoimmune disease is herein shown to be mediated in part by anti-ergotypic T cells, T cells that recognize and respond to the state of activation of other T cells. The anti-ergotypic response thus combines with the previously shown anti-idiotypic T cell response to regulate autoimmunity. 相似文献