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H. de Haan 《Euphytica》1952,1(1):60-61
Summary The English abstracting journal Plant Breeding Abstracts gives a satisfactory synopsis of books on plant breeding and of articles in this field that have appeared in general and professional journals.In the above survey are mentioned the following periodicals: Sveriges Utsädesföreningstidskrift (1891 ), Zeitschrift für Pflanzenzüchtung (1913 ), Der Züchter (1929 ), Agri Hortique Genetica (1943 ), Indian Journal of Genetics and Plant Breeding (1941 ), Melhoramento (1948 ), Annales de l'Amélioration (1951 ) and Euphytica, Netherlands Journal of Plant Breeding (1952 ).
Vaktijdschriften op het gebied van de plantenveredeling相似文献
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M. de Koning 《Forstwissenschaftliches Centralblatt》1925,47(10):706-716
Ohne Zusammenfassung 相似文献
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Umberto MOLINI Vimanuka MUTJAVIKUA Mari de VILLIERS Lourens de VILLIERS Alaster SAMKANGE Lauren M. COETZEE Siegfried KHAISEB Giovanni CATTOLI William G. DUNDON 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2022,84(5):707
Samples from eleven birds (chicken, dove and peacock) with symptoms of fowlpox, caused by the avipoxvirus (APV), were collected in seven different areas of the Windhoek district, Namibia between April and October 2021. A fragment of the 4b core protein and the DNA polymerase gene of APV were amplified by PCR from the DNA of the samples and sequenced. Phylogenetic analysis revealed that the viruses present in the chickens all belonged to clade A1 while the viruses in the doves and peacock were from subclade A3.1. This is the first report of subclade A3.1 avipoxvirus in peacock. In addition, all of the samples obtained from chickens were shown by PCR to be positive for the integration of reticuloendotheliosis virus while those from the doves and peacocks were negative. This study is the first characterization of avipoxvirus in Namibia and provides additional information on the presence of avipoxvirus in southern Africa. 相似文献
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Baolin Ge Chunyu Hou Bin Bao Zhilin Pan Jos Eduardo Mat Snchez de Val Jeevithan Elango Wenhui Wu 《Marine drugs》2022,20(6)
Fish collagen has been widely used in tissue engineering (TE) applications as an implant, which is generally transplanted into target tissue with stem cells for better regeneration ability. In this case, the success rate of this research depends on the fundamental components of fish collagen such as amino acid composition, structural and rheological properties. Therefore, researchers have been trying to find an innovative raw material from marine origins for tissue engineering applications. Based on this concept, collagens such as acid-soluble (ASC) and pepsin-soluble (PSC) were extracted from a new type of cartilaginous fish, the blacktip reef shark, for the first time, and were further investigated for physicochemical, protein pattern, microstructural and peptide mapping. The study results confirmed that the extracted collagens resemble the protein pattern of type-I collagen comprising the α1, α2, β and γ chains. The hydrophobic amino acids were dominant in both collagens with glycine and hydroxyproline as major amino acids. From the FTIR spectra, α helix (27.72 and 26.32%), β-sheet (22.24 and 23.35%), β-turn (21.34 and 22.08%), triple helix (14.11 and 14.13%) and random coil (14.59 and 14.12%) structures of ASC and PSC were confirmed, respectively. Collagens retained their triple helical and secondary structure well. Both collagens had maximum solubility at 3% NaCl and pH 4, and had absorbance maxima at 234 nm, respectively. The peptide mapping was almost similar for ASC and PSC at pH 2, generating peptides ranging from 15 to 200 kDa, with 23 kDa as a major peptide fragment. The microstructural analysis confirmed the homogenous fibrillar nature of collagens with more interconnected networks. Overall, the preset study concluded that collagen can be extracted more efficiently without disturbing the secondary structure by pepsin treatment. Therefore, the blacktip reef shark skin could serve as a potential source for collagen extraction for the pharmaceutical and biomedical applications. 相似文献
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Alkaloids are a large and structurally diverse group of marine-derived natural products. Most marine-derived alkaloids are biologically active and show promising applications in modern (agro)chemical, pharmaceutical, and fine chemical industries. Different approaches have been established to access these marine-derived alkaloids. Among these employed methods, biotechnological approaches, namely, (chemo)enzymatic synthesis, have significant potential for playing a central role in alkaloid production on an industrial scale. In this review, we discuss research progress on marine-derived alkaloid synthesis via enzymatic reactions and note the advantages and disadvantages of their applications for industrial production, as well as green chemistry for marine natural product research. 相似文献
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大麦黄花叶病毒的机械接种一般发病率较低,为提高其发病率,我们进行了缓冲液种类、用量,接种源种类,接种时苗龄,按种后苗培育时的温度、光照强度和时数等因素的研究。 相似文献