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971.
Three new anamorphic ascomycetous yeasts are described: Candida anglica (type strain NRRL Y-27079, CBS 4262), Candida cidri (type strain NRRL Y-27078, CBS 4241), and Candida pomicola (type strain NRRL Y-27083, CBS 4242). These three species were isolated from cider produced in the United Kingdom, and their identification was determined from unique nucleotide sequences in the species-specific D1/D2 domain of large subunit (26S) ribosomal DNA. Phylogenetic analysis of D1/D2 sequences placed C. anglica near Candida fragi, C. cidri near Pichia capsulata, and C. pomicola in the Pichia holstii clade. 相似文献
972.
Two ballistoconidium-forming yeast strains, CH 2.504 and CH 2.509, were isolated from the wilting leaves of Parthenocissus sp. collected in Yunnan, China in 1996. These two strains were assigned to the genus Bullera Derx by the characteristics of forming rotationally symmetric ballistoconidia, containing xylose in the cell hydrolysates
and having Q-10 as the major ubiquinone. Molecular phylogenetic analysis based on small subunit ribosomal RNA gene (18S rDNA)
and internal transcribed spacer (ITS) region sequences revealed that CH 2.504 is closely related to B. variabilis Nakase & Suzuki, while CH 2.509 is located in a clearly separate clade among the described Bullera species and related taxa. The results indicated that CH 2.509 represents a new species, for which Bullera anomala sp. nov. is the proposed name (type strain AS 2.2094T). Further DNA-DNA reassociation data showed that CH 2.504 also represents a distinct species, for which the name Bullera pseudovariabilis sp. nov. is given (type strain AS 2.2092T).
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
973.
Yeasts, isolated from different sources, were identified and tested for inhibition using YMA-MB plates seeded with Botrytis cinerea strains. A total of 42 yeast strains of 20 different species were tested in vitro for antagonism against 18 pathogenic B. cinerea strains. Pichia membranifaciens, P. anomala and Debaryomyces hansenii displayed the most important inhibitory effect against Botrytis strains. In small-scale trials, post-harvest application of P. membranifaciens CYC 1106 to apple wounds inhibited B. cinerea CYC 20010. Purified killer toxin from P. membranifaciens CYC 1106 inhibited B. cinerea CYC 20010. Results indicated that certain yeasts, or their toxins such us P. membranifaciens CYC 1106 killer toxin, might have potential as novel agents to control B. cinerea. 相似文献
974.
The effects of prolonged oral administration (21 days) of fumonisin B1 (FB1) and aflatoxin B1 (AFB1) were evaluated on male Wistar rats. The animals were housed in individual metabolic cages and submitted to the following treatments: 1-0 g AFB1 + 0 mg FB1/100g bw.; 2-72 g AFB1+ 0 mg FB1/100 g bw; 3-0 g AFB1 + 0.5 mg FB1 g bw; 4-0 g AFB1 + 1.5 mg FB1/100 g bw; 5-72 g AFB1 + 0.5 mg FB1/100g bw; 6-72 gAFB1 + 1.5 mg FB1/100g bw. On day 21, the rats were sacrificed for evaluation. The results showed that treated animals presented differences in body weight and absolute/relative weights of liver and kidney as well as altered hepatic function and cholesterol blood levels. Rats fed with the greatest doses of AFB1 and FB1 gained less weight (2.79 g/day) at the end of the experimental period; their blood concentrations of liver enzymes aspartate aminotransferase (AST) and alkaline phosphatase (AP) were above control levels (130.35 /l and 471.00 /l, respectively). Blood cholesterol increased in the groups treated with the highest dose ofFB1 or FB1 associated with AFB1. Histopathology revealed the occurrence of apoptosis in the liver of rats exposed to FB1. The association of aflatoxin B1 with fumonisin B1 at higher dose probably potentiated the effects of the higher dose of fumonisin B1acting singly.This revised version was published online in October 2005 with corrections to the Cover Date. 相似文献
975.
Oral tissue samples were studied using mid-IR fiber-optic attenuated total reflectance spectroscopy and other spectral techniques. The 1745 cm(-1) band, which is assigned to the ester group (C==O) vibration of triglycerides, is a reliable marker that is present in normal tissues but absent or a weak band in malignant oral tissues. Other bands such as C--H stretching bands and the amide bands are also helpful in distinguishing malignant tissues from normal tissues. Subtraction spectra confirmed the above conclusion. In addition, Raman spectroscopic measurements were in agreement with the results observed from FTIR spectra. 相似文献
976.
977.
Objectives This study was designed to determine whether older people perceive oral health as being important to Quality of Life (QoL) and if so, to identify the most important ways in which their lives are affected. In addition, to identify if subgroups of older people perceive its importance differently. Design: Nationwide qualitative face to face interviews with older people were carried out utilising the Office for National Statistics Omnibus survey in Great Britain. Subjects and methods 454 adults aged 65 or older took part in this study, part of a random probability sample of adults in the UK. Setting Respondents were interviewed in their homes. Results 72% (313) perceived their oral health status as important to their QoL through a variety of physical, social and psychological ways. Most frequently its impact on function: eating (29%, 126) and symptoms: comfort (14%, 59) were considered most important. Gender and social class variations were apparent (P<0.05). Conclusion Older people perceive oral health as being important to life quality in a variety of different ways. There are significant social class and gender variations which must be taken into consideration when assessing oral health needs of older people. 相似文献
978.
Frenkel HF 《Gerodontology》1999,16(2):75-80
Objective: To identify qualitatively carer staff attitudes, practices and clinical comments related to oral health care of functionally dependent nursing home clients. Design: Open-ended questions included in a longer quantitative questionnaire. Setting: 22 randomly selected nursing homes in the Bristol area. Subjects: 416 carers employed in these homes. Results: The majority of carers thought that clients had a right to good oral health, accepted the carers' role in helping clients with oral and denture hygiene, but recognised that oral health care provision was deficient. However, some carers believed oral health care to be solely the clients' responsibility despite high disability levels. Main barriers to providing oral health care were low prioritisation of oral health by nursing management, lack of co-operation from cognitively impaired clients, and lack of training. Carers were critical of homes' lack of arrangements for routine professional dental cheeks, lack of commitment to staff training, low standards of oral health care by colleagues, and lack of provision of oral hygiene aids and cleansing materials for clients. Many responses indicated ways in which nursing home oral health care could be improved. Carers reported contrasting experiences of dental treatment, and deplored recent decreased availability of subsidised dental care. Conclusions: Carers' generally positive attitudes towards clients' oral health care should encourage health educators. Insights gained from qualitative data can help to identify the less obvious causes for poor oral care delivery, which can then be addressed in education and training initiatives in nursing home settings. 相似文献
979.
The occurrence and diversity of yeasts in seawater was investigated in a study site located 20 Km off Faro, Portugal, above
the álvares Cabral Trench. A total of 43 water samples from different layers (above the permanent thermocline, under the thermocline
and near the bottom) and directly from the surface, originated 234 isolates. All the isolates were identified using a molecular
approach that included, in a first stage, MSP-PCR fingerprinting. A total of 31 MSP-PCR classes were formed, 8 for the pigmented
yeasts and 23 for the non-pigmented yeasts. The pink coloured isolates were identified by direct comparison of the new fingerprints
with those obtained for representative strains of the various species. For identification of the non-pigmented yeasts, a representative
isolate of each MSP-PCR class was selected for sequence analysis and compared with reference sequences. The five most abundant
yeast species were Sakaguchia dacryoidea, Pseudozyma aphidis, Rhodosporidium babjevae, R. diobovatum and Debaryomyces hansenii. The distribution of isolates and species in the major taxonomic groups indicated that the number of basidiomycetous yeasts
and their diversity are prevalent in relation to their ascomycetous counterpart. Diversity indices were determined and superficial
water and water near the bottom had the highest diversity. The sampling effort effectiveness was estimated, and found to correspond
to approximately 60% of the species present. MSP-PCR identification proved suitable for pigmented basidiomycetous yeasts and,
when used in conjunction with sequence analysis, was effective for the characterization of non-pigmented populations. Our
results indicate that the MSP-PCR fingerprinting method is appropriate for the characterization of large groups of isolates
due to its simplicity and good reproducibility.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
980.
A culture was obtained from a spore print of a basidiocarp of Mycogloea nipponica collected in Taiwan. A yeast stage and basidia identical to those of M. nipponica developed in laboratory media. The Taiwanese specimen of M. nipponica and its yeast anamorph were characterised in the present study. Comparative morphological, molecular, and ultrastructural
studies indicated that the yeast stage can be assigned to the genus Kurtzmanomyces. The revealed connection between the sexual species Mycogloea nipponica and the asexual genus Kurtzmanomyces demonstrates the importance of anamorphic characteristics in the modern systematics of heterobasidiomycetous fungi.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献