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61.
The cellular location of proteases in Candida albicans   总被引:1,自引:0,他引:1  
Vacuoles prepared from yeast cells of Candida albicans were enriched in proteinase ycaB (EC 3.4.21.48) but not in aminopeptidase or beta-glucosidase. Proteinase ycaB, assayed in situ, increased 1.5-fold during starvation whereas aminopeptidase activity decreased by 25%. Proteinase ycaB increased a further 1.5-fold during germ-tube formation.  相似文献   
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 The floral morphology of seven Oxypetalum species and, in particular, the spatial relationship between the five stigmatic chambers and two separate ovaries of their flowers with respect to transmission of the pollen tube are studied. In all species, except O. banksii subsp. banksii, floral morphology is similar to that in other Asclepiadeae, and the flowers pollinated with one pollinium develop only one follicle, which means compitum absence. In O. banksii subsp. banksii flowers, the secretory interstaminal tissue lines the inner walls of the stigmatic chambers as in the other species studied, but it also reaches the upper part of the inner surface of the filament tube, where it surrounds the styles, an unprecedented feature for Asclepiadaceae. This tissue secretes nectar and mucilage; the latter acts as transmitting medium for the growth of pollen tubes from pollinia inserted and hydrated in stigmatic chambers (“hyperstigmas”). Mucilage also functions as an extragynoecial compitum: in flowers pollinated with one pollinium both carpels develop into a follicle. Received August 28, 2001; accepted April 9, 2002 Published online: October 14, 2002 Addresses of the authors: Milene Faria Vieira (e-mail: mfvieira@mail.ufv.br), Departamento de Biologia Vegetal, Universidade Federal de Vi?osa, 36571-000, Vi?osa, Minas Gerais, Brazil. George John Shepherd, Departamento de Botanica, Instituto de Biologia, Universidade Estadual de Campinas, C.P. 6109, 13083-970, Campinas, S?o Paulo, Brazil.  相似文献   
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Currently the management of adult victims of violence by general practitioners and accident and emergency departments is reactive, concerned almost exclusively with the management of physical injuries. Professor Jonathan Shepherd outlines some ideas for a more proactive approach on the part of doctors to improve the protection and support of vulnerable people; to deal with psychological sequelae; to take the responsibility of making an official complaint to the police away from seriously injured people, who are unable to give or withhold consent to disclosure; and to prevent assailants inflicting further injuries. We asked a sociologist, a psychiatrist, a moral philosopher, and a police surgeon for their comments.  相似文献   
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The relative metobolic turnover rates of labeled histone fractions and of their labeled acetyl groups were determined in random cultures of exponentially-growing mammalian cells. Both the parent histones and their acetyl groups were conserved, neither exhibiting detectable metabolic turnover. The significance of these observations is discussed.  相似文献   
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Probiotics and Antimicrobial Proteins - Gamma-aminobutyric acid (GABA) is a principal inhibitory neurotransmitter in the central nervous system and is produced by irreversible decarboxylation of...  相似文献   
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Melanoma is a disease associated with a very high mutation burden and thus the possibility of a diverse range of oncogenic mechanisms that allow it to evade therapeutic interventions and the immune system. Here, we describe the characterization of a panel of 102 cell lines from metastatic melanomas (the NZM lines), including using whole‐exome and RNA sequencing to analyse genetic variants and gene expression changes in a subset of this panel. Lines possessing all major melanoma genotypes were identified, and hierarchical clustering of gene expression profiles revealed four broad subgroups of cell lines. Immunogenotyping identified a range of HLA haplotypes as well as expression of neoantigens and cancer–testis antigens in the lines. Together, these characteristics make the NZM panel a valuable resource for cell‐based, immunological and xenograft studies to better understand the diversity of melanoma biology and the responses of melanoma to therapeutic interventions.  相似文献   
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