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91.
We investigated the prevalence and phenotypic variation of Candida species in oral lichen planus (OLP) and the therapeutic implications of our findings. Eighty patients with clinically and histopathologically confirmed cases of OLP (64 non-erosive, 16 erosive) and a control group of 80 healthy individuals with no predisposing factors for oral candidiasis were examined for evidence of Candida infection. Oral swabs and smears were obtained for cytology and culture. Identification, speciation and antifungal susceptibility tests of Candida isolates were performed using an automated microbial identification system. Fifty percent of erosive OLP cases, 28% of non-erosive cases and none of the controls showed evidence of Candida. Candida albicans was found predominantly in non-erosive OLP, while other Candida species were predominate in erosive OLP. Non-Candida albicans isolates (C. glabrata, C. krusei) were resistant to the commonly used antifungals, clotrimazole and fluconazole. Candida infection is common in cases of OLP. We recommend antifungal sensitivity testing prior to antifungal therapy for the erosive form of OLP. 相似文献
92.
Histone V (2fc) from chick erythroctes was used in the study of its interaction with DNA from various sources. Complexes between this histone and DNA were formed using the procedure of continuous NaCl gradient dialysis in urea. Two physical methods, namely thermal denaturation and circular dichroism (CD), were used as analytical tools. Thermal denaturation of nucleohistone V with chick or calf thymus DNA shows three melting bands: band I at 45-50 degrees corresponds to free base pairs; band II at 75-79 degrees, and band III at 90-93 degrees correspond to histone-bound base pairs. In histone-bound regions, there are 1.5 amino acid residues/nucleotide in nucleohistone V. In contrast, a value between 2.9 and 3.3 was determined for nucleohistone I (fl) (H. J. Li (1973), Biopolymers 12, 287). Similar melting properties have been observed for histone V complexed with bacterial DNA from Micrococcus luteus. Histone V binding to DNA induces a slight transition from a B-type CD spectrum to a C-type spectrum. Trypsin treatment of nucleohistone V reduces melting band III much more effectively than band II. Such a treatment also restores DNA to B conformation in the free state. Reduction of the melting bands of nucleohistone V by polylysine binding follows the order of I greater than II greater than III, accompanied by the increase of a new band at 100 degrees. When two bacterial DNAs of varied A + T (adenine + thymine) content simultaneously compete for the binding of histone V, the more (A " T)-rich DNA is selectively favored. Under experimental conditions described here, Clostridium perfringens DNA with 69% A + T is bound by histone V in preference to chicken DNA with 56% A + T although the latter has natural sequences for histone V binding. 相似文献
93.
The pattern of the digestive vasoactive intestinal polypeptide (VIP)-ergic innervation is described immunohistochemically in the hedgehog Erinaceus europaeus. This animal is a small-sized, wild, nocturnal, lower eutherian mammal whose gastrointestinal tract shows some similarities with the avian gut. The myenteric plexus of the stomach, the mucosa of the small intestine and the circular muscle layer of the large intestine are the best VIP-innervated structures. The pattern of the positive innervation is similar to that described in other mammals and in some bird species. The widespread diffusion of the neuropeptide in the gut is probably due to the importance of its functions in the digestive physiology. 相似文献
94.
Effect of pH on growth of mixed cultures in batch reactor 总被引:2,自引:0,他引:2
This work has studied the effect of pH on specific growth rate mu, yield factor Y, and specific substrate consumption rate U for two mixed microbial populations (sludge A and B) in a batch reactor with a limiting substrate (phenol). The mathematical analysis of mu and U as a function of pH has been applied not only to the results of the present work but also to other published data. On the basis of the results obtained, the following remarks can be made: (a) The effect of pH on bacterial activity differed for the two sludges; (b) variations in pH of one unit more or less than optimum pH can give rise to appreciable variations in mu and U; and (c) with regard to the mixed populations used in this study, the mu or U and pH data for the range investigated can be suitably described by a parabolic relation. 相似文献
95.
R. Scozzari C. Iodice D. Sellitto R. Brdicka G. Mura A. S. Santachiara-Benerecetti 《Human genetics》1984,68(4):314-317
Summary The electrophoretic and thermostability polymorphisms of the PGM
1 locus were examined in about 700 Czechoslovakians (Prague) and 3000 Italians. The Italian sample consisted of individuals from Pavia (Northern Italy), Viareggio and Rome (Central Italy) and Naples (Southern Italy). The eight PGM
1 alleles, PGM
1
1Str
, PGM
1
1Sts
, PGM
1
1Ftr
, PGM
1
1Fts
, PGM
1
2Str
, PGM
1
2Sts
, PGM
1
2Ftr
, PGM
1
2Fts
, have been considered as combinations of mutations at three different sites, 1/2 S/F and tr/ts, within the PGM
1 gene and their frequencies discussed in terms of linkage disequilibrium between these sites. All pairwise differences between the samples were significant except for Pavia-Viareggio and Viareggio-Rome. The frequencies of the PGM
1
ts
alleles have been found to range from 0.0981 (Prague) to 0.0546 (Naples) and can be ordered according to a North-South cline.This paper is dedicated to Professor Giuseppe Montalenti in occasion of his 80th birthday 相似文献
96.
97.
Life histories of two populations of Tanymastix stagnalisfrom sites in central Italy, differing in climate and altitude above sea level, were compared to obtain information on the tolerance limits of this species.Temperature was the main factor affecting the biology of Tanymastix stagnalis. Significant differences in growth patterns occurred at different sites. A colder climate induced delayed hatching, slower differentiation and maturation, but a longer life span in the mountain population (Forca Canapine) than in the plain (Fosso dei Mergani).Both populations exhibited an initial fluctuating sex ratio, which later became female biased, a pattern which could be the consequence of adaptation to the unstable nature of the biotopes studied. 相似文献
98.
99.
100.
Piero Cossu Fabio Scarpa Daria Sanna Tiziana Lai Gian Luca Dedola Marco Curini‐Galletti Laura Mura Nicola Fois Marco Casu 《Molecular ecology》2019,28(12):3012-3024
Aquaculture finfish production based on floating cage technology has raised increasing concerns regarding the genetic integrity of natural populations. Accidental mass escapes can induce the loss of genetic diversity in wild populations by increasing genetic drift and inbreeding. Farm escapes probably represent an important issue in the gilthead sea bream (Sparus aurata), which accounted for 76.4% of total escapees recorded in Europe during a 3‐year survey. Here, we investigated patterns of genetic variation in farmed and wild populations of gilthead sea bream from the Western Mediterranean, a region of long gilthead sea bream farming. We focused on the role that genetic drift may play in shaping these patterns. Results based on microsatellite markers matched those observed in previous studies. Farmed populations showed lower levels of genetic diversity than wild populations and were genetically divergent from their wild counterparts. Overall, farmed populations showed the smallest effective population size and increased levels of relatedness compared to wild populations. The small broodstock size coupled with breeding practices that may favour the variance in individual reproductive success probably boosted genetic drift. This factor appeared to be a major driver of the genetic patterns observed in the gilthead sea bream populations analysed in the present study. These results further stress the importance of recommendations aimed at maintaining broodstock sizes as large as possible and equal sex‐ratios among breeders, as well as avoiding unequal contributions among parents. 相似文献