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991.
I M Badalova B N Mishan'kin I Iu Suchkov 《Zhurnal mikrobiologii, epidemiologii, i immunobiologii》1987,(5):24-28
In two different strains of cholera vibrios two recA-dependent plasmids, pVib I (1.9-2.2 Md) and pVib II (5.2-5.8 Md), have been detected. These plasmids determine the synthesis of vibriocin, coagulase and fibrinolysin, which has been established by the cotransformation of the DNA of plasmids pVib I and pBR322 and by the transfer mobilization with the use of plasmid RP4. 相似文献
992.
Development of ovaries in bovine fetuses 总被引:1,自引:0,他引:1
The growth of ovaries, development of germ cells, formation of sex cords, folliculogenesis and dependence of these processes on the gonad morphogenesis stages were studied on 68 embryos and foetuses at the age of 1.5 to 9 months. Sex differentiation of ovaries was shown to take place in 1.5 month old embryo. The cords of connective tissue's cortical stroma appear also in 1.5 month old embryo, they develop in the dorsoventral direction and reach the gonad's covering epithelium in 6 month old foetuses. The formation of the medulla rudiment starts in 1.5 month old embryo when the gonad is separated from mesonephros and connected with it via the ovary gate. In 4 month old foetuses the ovary net transforms into a stellate structure. Important morphogenetic processes, such as the development of the ovary somatic elements, entry of the oocytes into meiotic prophase, formation of the sex cords and folliculogenesis, develop in the dorsoventral direction Germ cells in 9 month old foetuses are enclosed into primordial or, growing follicles. 相似文献
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994.
Ethnobotanical review of wild edible plants in Spain 总被引:5,自引:0,他引:5
JAVIER TARDÍO MANUEL PARDO-DE-SANTAYANA RAMÓN MORALES 《Botanical journal of the Linnean Society. Linnean Society of London》2006,152(1):27-71
This paper compiles and evaluates the ethnobotanical data currently available on wild plants traditionally used for human consumption in Spain. Forty-six ethnobotanical and ethnographical sources from Spain were reviewed, together with some original unpublished field data from several Spanish provinces. A total of 419 plant species belonging to 67 families was recorded. A list of species, plant parts used, localization and method of consumption, and harvesting time is presented. Of the seven different food categories considered, green vegetables were the largest group, followed by plants used to prepare beverages, wild fruits, and plants used for seasoning, sweets, preservatives, and other uses. Important species according to the number of reports include: Foeniculum vulgare , Rorippa nasturtium-aquaticum , Origanum vulgare , Rubus ulmifolius , Silene vulgaris , Asparagus acutifolius , and Scolymus hispanicus . We studied data on the botanical families to which the plants in the different categories belonged, overlapping between groups and distribution of uses of the different species. Many wild food plants have also been used for medicinal purposes and some are considered to be poisonous. This review highlights the rich traditional knowledge on edible plants that has remained in rural Spain. Until recently, many wild plants were used as dietary supplements. However, most of this knowledge survives only in the memory of the elderly, and will probably disappear in a few decades. © 2006 The Linnean Society of London, Botanical Journal of the Linnean Society , 2006, 152 , 27–71. 相似文献
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N R Krieg 《Canadian journal of microbiology》1988,34(4):536-540
Classification of bacteria evolved from limited subjective groupings to general, more objective arrangements based on overall phenotypic similarities. However, classifications based on phenotypic characters lack stability, whereas those based on genetic relatedness tend to be stable. DNA-DNA hybridization has proven to be extremely useful in resolving taxonomic problems at the species level. Broad relationships among bacteria have been identified by comparing ribosomal RNA cistrons; however, many groups based on ribosomal RNA analysis are not easily definable in terms of phenotypic similarities. Unless resolved, these problems could lead to the establishment of two separate classification systems, one phylogenetic and the other practical. 相似文献