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71.
目的分析博尔纳病病毒(Borna disease virus,BDV)H1766株对BALB/c小鼠的感染性。方法选择病毒滴度为2.0×107FFU/ml的BDV病毒液分别对新生和成年BALB/c小鼠进行脑内接种,并用相同病毒液对原代培养的新生BALB/c小鼠脑细胞进行接种。经过一定时间的病毒作用后分别提取总RNA,采用巢式RT-PCR方法检测BDV-p40基因,并通过免疫组化方法检测脑内接种脑组织中BDV-P40蛋白。结果脑内接种病毒的小鼠脑组织中可以检测到BDV-p40基因和BDV-P40蛋白,培养的小鼠脑细胞中可以检测到BDV-p40基因。结论BDVH1766株可以感染新生和成年的BALB/c小鼠。 相似文献
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DA Rosa AC Lessinger AC DE Azeredo-Espin AM Torres TT 《Molecular ecology resources》2008,8(5):971-973
The horn fly, Haematobia irritans (L.) (Diptera: Muscidae), is a cosmopolitan livestock pest that has caused a great negative impact on the animal production sector throughout the world. Here, we describe 10 polymorphic microsatellite loci isolated from H. irritans. The number of alleles found ranged from two to eight per locus and the expected heterozygosity from 0.1421 to 0.7702. These loci are potentially useful for the fine-scale genetic characterization of horn fly populations and provide fundamental information for pest management and planning of control programs. 相似文献
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GUO XING ZHONG JUN DA SU QING WEN SUN BING HUA JIAO Department of Biochemistry Molecular Biology Second Military Medical University Shanghai School of Life Sciences Medical Engineering Tongji University Shanghai China Shangha 《Cell research》2001,(4)
INTRODUCTIONEstrogen has been known to exert extensive effects via estrogen receptor (ER) on diverse physio-logical and develoPmental functions of the brain[1,2]. It has been observed that the distribution ofthe classical ER subtype-a (ERa) and the recentlycharacterized novel ER subtype--fi (ERg), and theirexpression patterns (ERcr/ERfi) vary greatly amongvarious brain regions[1, 3]. These evidences suggestthat each ER subtype may play a different role inestrogen's effects on the br… 相似文献
75.
Portions of the cloned mating-type (MT) loci (mt(+) and mt(-)) of Chlamydomonas reinhardtii, defined as the approximately 1-Mb domains of linkage group VI that are under recombinational suppression, were subjected to Northern analysis to elucidate their coding capacity. The four central rearranged segments of the loci were found to contain both housekeeping genes (expressed during several life-cycle stages) and mating-related genes, while the sequences unique to mt(+) or mt(-) carried genes expressed only in the gametic or zygotic phases of the life cycle. One of these genes, Mtd1, is a candidate participant in gametic cell fusion; two others, Mta1 and Ezy2, are candidate participants in the uniparental inheritance of chloroplast DNA. The identified housekeeping genes include Pdk, encoding pyruvate dehydrogenase kinase, and GdcH, encoding glycine decarboxylase complex subunit H. Unusual genetic configurations include three genes whose sequences overlap, one gene that has inserted into the coding region of another, several genes that have been inactivated by rearrangements in the region, and genes that have undergone tandem duplication. This report extends our original conclusion that the MT locus has incurred high levels of mutational change. 相似文献
76.
Anthropology in the 20th Century and Beyond 总被引:1,自引:0,他引:1
Ward H. Goodenough 《American anthropologist》2002,104(2):423-440
This article reviews the growth of knowledge in the four fields of anthropology. It is not an intellectual history but, rather, focuses on what I consider to have been the important developments in substantive knowledge. [Keywords: U.S. anthropology, four fields, 20th century, substantive knowledge] 相似文献
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C. PRADO E CASTRO A. SERRANO P. MARTINS DA SILVA M. D. GARCÍA 《Medical and veterinary entomology》2012,26(4):417-431
Information on Diptera community, seasonality and successional patterns in every geographical region is fundamental for the use of flies as forensic indicators of time of death. In order to obtain these data from the Lisbon area (Portugal), experiments were conducted during the four seasons of the year, using piglet carcasses as animal models. Five stages were recognized during the decomposition process. The stages, besides visually defined, could be separated taking into account the occurrence and abundance of the specific groups of Diptera collected. In general, the bloated stage recorded higher abundance and species‐richness values. Seventy‐one species were identified, belonging to 39 families, in a total of 20 144 adult Diptera collected. Autumn yielded the highest values of species richness, whereas winter had the lowest. In all seasons of the year, Calliphoridae was the dominant family; Muscidae and Fanniidae were very abundant as well. Calliphora vicina Robineau‐Desvoidy, Calliphora vomitoria (Linnaeus), Chrysomya albiceps (Wiedemann), Lucilia ampullacea Villeneuve, Lucilia caesar (Linnaeus), Lucilia sericata (Meigen) (Calliphoridae), Hydrotaea ignava (Harris), Muscina prolapsa (Harris), Synthesiomyia nudiseta (van der Wulp) (Muscidae), Piophila megastigmata McAlpine, Stearibia nigriceps (Meigen) (Piophilidae) and Nemopoda nitidula (Fallén) (Sepsidae) were revealed to be very important members of the Diptera community collected. The necrophagous behaviour, demonstrated by their immatures, using carrion as a food source makes them useful forensic indicator species. Also of relevance is the presence of Chrysomya megacephala (Fabricius), S. nudiseta and P. megastigmata, foreign species established in the local carrion communities. This study also marks the first record of S. nudiseta in Portugal. 相似文献
80.
Topological distribution of two connexin32 antigenic sites in intact and split rodent hepatocyte gap junctions 总被引:25,自引:12,他引:13
The membrane topology of connexin32, a principal polypeptide of gap junctions in diverse cell types, has been studied in rat and mouse hepatocyte gap junctions using site-specific antisera raised against synthetic oligopeptides corresponding to amino acid sequences deduced from cDNA clones. Based on published hydropathicity maps and identified protease-sensitive cleavage sites, oligopeptides were synthesized corresponding to two hydrophilic domains of connexin32, one predicted to face the cytoplasm, the other predicted to be directed extracellularly. Antisera were raised to keyhole limpet hemocyanin conjugates of the oligopeptides and used to map the distribution of their antigens using indirect immunocytochemistry on isolated gap junctions. The results directly demonstrated the cytoplasmic orientation of an antigen contained within amino acids 98-124 of the connexin32 sequence. The extracellular space in intact, isolated gap junctions is too small to permit binding of antibody molecules, necessitating the experimental separation of the junctional membranes to expose their extracellular surfaces using a urea/alkali procedure. While an antigen contained within amino acids 164-189 was visualized on the extracellular surfaces of some of the separated junctional membranes, variability in the observations and in the splitting procedure left ambiguities concerning the biological relevance of the observations after the denaturing conditions necessary to separate the junctional membranes. Using a different approach, however, the antigen could be exposed in intact liver using a hypertonic disaccharide junction-splitting procedure. The period of time of antigen exposure at the cell surface appears to peak at 30 s and disappear by 2-4 min. Taken together, these data demonstrate the extracellular orientation of an antigen contained within amino acids 164-189, which may be involved in cell-cell interaction within the gap junction. 相似文献