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51.
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E Schr?der 《Acta anatomica》1978,100(4):478-489
The utero-ovarian vascularisation of the non-pregnant rat was investigated, described and morphometrically evaluated. The ovarian and uterine arteries anastomose together giving up a ramus ovaricus. The leaving of these vessels from their main trunks varies to each body side, just as their length and width. Several segmental arteries arise from each uterine artery to the corpus uteri also side-specifically. Coiled circular arteries are found. The uterine cervical vascularisation is described separately. Different regulating effects on the function of the vessels are discussed. 相似文献
54.
G von der Emde 《European journal of morphology》1999,37(2-3):200-205
Weakly electric fish produce electric signals with a specialised organ in their tail. In addition, they are electrosensitive and can perceive their self-generated signals (for electrolocation) and electric signals of other electric fishes (for electrocommunication). Mormyrids possess three types of peripheral electroreceptor organs, one used for electrocommunication and two types involved in electolocation. They are innervated by afferent fibres, which project to different zones in the electrosensory lateral line lobe (ELL) in the medulla. Brain circuits for electrolocation and electrocommunication are separated almost throughout the whole brain. Electrolocation pathways run from the ELL-cortex to the torus semicircularis of the midbrain and then via the valvula cerebelli towards the telencephalon. Pathways involved in electrocommunication run from the nucleus of the ELL to another part of the torus and from there through the isthmic granule nucleus to the valvula. In addition, a pathway via the preglomerular complex to the telencephalon might exist. In both the electrolocation and the electrocommunication circuits, prominent recurrent pathways are present. 相似文献
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J. P. van der Walt 《Antonie van Leeuwenhoek》1992,62(4):247-250
The Lipomycetaceae (Endomycetales) are known from the generaDipodascopsis, Lipomyces andZygozyma with budding anamorphic states inMyxozyma. The family is easily recognized culturally and physiologically but is phenotypically and ecologically extremely diverse. This natural taxon is phylogenetically distinct from the Saccharomycetaceae, but probably related to the Dipodascaceae. The possible evolution of the lipomycetaceous anamorphs is discussed. 相似文献
58.
Control of antigenic variation in African trypanosomes 总被引:8,自引:0,他引:8
L H Van der Ploeg 《The New biologist》1991,3(4):324-330
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60.
Heterologous gene expression in Lactococcus lactis subsp. lactis: synthesis, secretion, and processing of the Bacillus subtilis neutral protease 总被引:1,自引:0,他引:1
M van de Guchte J Kodde J M van der Vossen J Kok G Venema 《Applied and environmental microbiology》1990,56(9):2606-2611
The Bacillus subtilis nprE gene lacking its own promoter sequence was inserted in the lactococcal expression vector pMG36e. Upon introduction of the recombinant plasmid into Lactococcus lactis subsp. lactis strain MG1363, neutral protease activity could be visualized by the appearance of large clearing zones around colonies grown on milk agar plates. By measuring the activities of the neutral protease and the intracellular enzyme lactate dehydrogenase in culture supernatants and cell fractions, it was demonstrated that the neutral protease was actively secreted into the growth medium. This was corroborated by using the Western blot (immunoblot) technique, which showed the presence of the mature form of the neutral protease in the culture supernatant. On the basis of these results, it is concluded that the B. subtilis neutral protease gene was expressed in L. lactis and that the gene product was secreted into the growth medium and was apparently correctly processed to produced a biologically active protein. The secretion of this particular enzyme may be helpful in achieving accelerated cheese ripening. 相似文献