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1.
I. Rosario G. Soro S. Déniz O. Ferrer F. Acosta D. Padilla B. Acosta 《Mycopathologia》2010,169(4):315-319
Columba livia is an important reservoir and carrier of Cryptococcus neoformans, Cryptococcus uniguttulatus, Cryptococcus laurentii and Cryptococcus albidus. Upper digestive tract of this species is also known as a habitat for Cryptococcus neoformans. Given the increasing clinical interest of this microorganism, 331 swabs from crop and 174 dropping samples from pigeon lofts
in Grand Canary Island have been studied. The obtained results show an extensive presence samples 81 positive (24.47%) of
Cryptococcus spp. in analysed crops: 32 (9.66%) for C. neoformans, 24 (7.2%) for C. uniguttulatus, 23 (6.9%) for C. albidus and 2 (0.6%) for C. laurentii. In the same way, Cryptococcus spp was also isolated in 82 (47.13%), dropping samples: C. neoformans in 59 (33.9%), C. uniguttulatus, in 9 (5.17%), C. laurentii in 8 (4.59%) and C. albidus in 6 (3.44%) of the investigated samples, respectively. The cryptococcosis produced by species of cryptococci other than C. neoformans has become more important during the last decade, supporting the study on the role of pigeon in the epidemiology of this
disease. 相似文献
2.
Trichogramma cordubensis n. sp. is a parasite ofHeliothis armigera Hb. eggs in cotton crops in western Andalusia. Reproduced onEphestia kuehniella Zeller eggs, it is described morphologically and compared withT. chilonis Ishii andT. evanescens Westwood as both present similarities with this species.T. cordubensis can be distinguished in the male genitalia by the shape of the dorsal expansion of the gonobase and the size, shape and relative position of the median ventral projection. Male antennal setae are longer inT. cordubensis than in the other 2 species. In addition, unlikeT. chilonis andT. evanescens, T. cordubensis is thelytokous at 20°C. in our laboratory, though males and gynandromorphs can be obtained by altering the rearing temperature, this being another difference of this species. 相似文献
3.
D. Padilla F. Acosta J. A. García F. Real Jose R. Vivas 《Archives of microbiology》2009,191(3):191-198
Hafnia alvei, a Gram negative bacillus related to the Enterobacteriaceae family, is considered an opportunistic pathogen of several animal species and humans. In this communication, we describe
fimbrial-like structures from different strains of H. alvei that cannot be easily ascribed to any of the previously reported fimbrial types in this species (type I or type III). Polymerase
chain reaction (PCR) and immunofluorescence assays were carried out to study fimbriae and flagella in H. alvei strains isolated from different sources. No correlation between the results obtained by PCR and those obtained by phenotypic
methods were found, and the antibodies used gave cross or different recognition patterns of the surface structures present
in these strains. We report as well that strain and growth temperature influence fimbriation and expression of flagella in
human and animal isolates of H. alvei. This study also indicates that the absence of fimbriae have a significant positive influence on the initial adhesion of
H. alvei to human epithelial cells. 相似文献
4.
Unpublished portions of the synthesis of a phosphinate-phosphonate diether analog of CDPdiacylglycerol are reported. The liponucleotide analog was found to be a very powerful inhibitor of platelet PI synthetase; kinetic data suggest a competitive inhibition mechanism. The structural specificity of CDPdiacylglycerol for liponucleotide-mediated biosynthetic reactions is discussed. 相似文献
5.
A Soler C García del Río L García-Torres F Vargas A Martín-Andrés C Osorio 《Revista Espanola de Fisiología》1985,41(1):107-116
The effects of changes in arterial pressure and in circulating volume on Plasma Renin Activity (PRA) in the intact rat were compared by two experimental procedures. Gradual volume depletion was induced by intraperitoneal injection of a hyperoncotic polyethyleneglycol solution (PEG) in absence of acute changes in Systolic Arterial Pressure (SAP). SAP was measured in the conscious state by the tail cuff technique. Plasma Protein Concentration (PPC) and Hematocrit (Hct) increases after PEG injection were compared as the index for measuring the Plasma Volume Reduction (PVR). PRA showed a significant (p less than 0.001) linear relationship with PPC, suggesting a direct dependence of renin secretion on volume depletion. Acute changes in the circulating volume were induced by controlled hemorrhages of 5.0, 10.0, 15.0 and 20.0 ml of blood/kg body weight. The increase in PRA showed a significant relationship with the changes in circulating volume, but it did not show any dependence on the changes in Mean Arterial Pressure (MAP). Our results suggest that, in the intact and conscious rat, renin secretion responds to the information from the cardiopulmonary volume receptors rather than to that from the high pressure receptors. 相似文献
6.
The tyrosylsulfotransferase activities of rat cerebral fractions transferring [35S]sulfate groups from 3'-phosphoadenosine 5'-[35S]phosphosulfate to either Boc-cholecystokinin-8 (in non-sulfated form) or the acidic amino acid polymer (Glu, Ala, Tyr)n (6:3:1) were compared. They appear similar regarding subcellular distribution (both being enriched in the microsomal fraction) and inhibition by an excess of the acidic amino acid polymer, NaCl or 2,6-dichloro 4-nitrophenol. These results obtained with artificial substrates suggest that identical (or closely similar) tyrosylsulfotransferases are responsible for sulfation of tyrosine residues of several secretory proteins from various tissues. 相似文献
7.
J L Vargas E O'Connor E Roche E Knecht S Grisolia 《Biochemical and biophysical research communications》1987,147(2):535-541
Many functional, morphological and biochemical differences among hepatocytes from different acinar zones have been described. Therefore, it will facilitate studies on liver metabolism rapid, non-destructive procedures to isolate hepatocytes from these zones. Flow cytometry is a new powerful tool which, however, has not been used thus far to accomplish the separation of hepatocytes from different acinar zones. We describe here various cytometric parameters which characterize hepatocyte populations, separated by isopycnic centrifugation in Percoll gradients. The intraacinar origin of the different hepatocytes was assessed by enzymatic and morphological measurements. 相似文献
8.
Cultivar and pH effects on competition for nodule sites between isolates of Rhizobium in beans 总被引:2,自引:0,他引:2
Two experiments were carried out to evaluate the effect of acidity on bean-Rhizobium competition for nodule sites. SevenPhaseolus vulgaris host cultivars differing in acid-pH tolerance were grown in sand culture, and irrigated using a sub-irrigation system and nutrient solutions of pH 4.5, 5.0, 5.5, and 6.0. A mixed inoculant of two antibiotically markedRhizobium leguminosarum bvphaseoli strains CIAT899 (acid-tolerant) and CIAT632 (acid-sensitive) was used. The acid-tolerant CIAT899 dominated CIAT632 in nodule occupancy across all cultivars and pH treatments. Although several of the varieties had previously been identified as PH-tolerant, and these cultivars performed better than those reported to be acid sensitive, all showed a marked increase in nodulation and plant development when the pH was raised from 4.5 to 6.0. The second experiment using a modified Leonard jar system varied the inoculation ratio between CIAT899 and UMR1116 (acid-sensitive, inefficient in N2-fixation) and contrasted nodulation response for the bean varieties Preto 143 (pH-tolerant) and Negro Argel (pH-sensitive) at 3 pH treatments (4.5, 5.5, 6.5). There was a significant effect of host cultivar, ratio of inoculation, and pH on the percentage of nodule occupancy by each strain. At low pH CIAT899 had higher nodule occupancy than UM1116 in the variety Negro Argel but had the same percentage of nodulation when the variety was Preto 143. Increasing the cell concentration of UMR1116 produced more inefficient nodules at all treatment combinations and reduced plant growth for both cultivars used. 相似文献
9.
P Montilla J A Navarro J Montilla J Vargas M C Mu?oz 《Revista Espanola de Fisiología》1989,45(4):323-326
The effect of ACTH (100 micrograms/animal/day, i.p.), dexamethasone (75 micrograms/animal/day, s.c.), both for three consecutive days, and adrenalectomy, with or without dexamethasone, maintained according to the group, one, two or three days, on the plasmatic testosterone and corticosterone levels, has been studied in adult male Wistar rats. ACTH and adrenalectomy produced a high decrease in testosterone levels (p less than 0.001 for the three days studied). Dexamethasone produced lower testosterone levels in the first day followed by partial recuperation between the second and the third days of its administration. Dexamethasone produced the effects mentioned for intact animals. The changes in corticosterone levels were according to an adequate response of the hypothalamus-pituitary-adrenal system under these experimental circumstances. ACTH exerts an inhibitory effect on testosterone secretion in the rat, so that such an effect from the data obtained after adrenalectomy and simultaneous dexamethasone injections, does not seems to be mediated either by the presence of adrenals or high corticosterone levels. 相似文献
10.
L C Stephens T E Schultheiss K J Vargas D M Cromeens K N Gray K K Ang 《Journal of medical primatology》1989,18(5):383-396
The various glands of rhesus monkey eyelids and human eyelids are similar. Numerous modified sebaceous glands are located along the tarsus. These conform with the meibomian glands, while typical sebaceous glands associated with the hair follicles of the lashes are consistent with the glands of Zeis. Lobules of accessory lacrimal tissue, corresponding to the glands of Krause and Wolfring, are located in the conjunctiva of the fornix and along the orbital border of the tarsal plate. Goblet cells are plentiful in the mucosa of the palpebral and bulbar conjunctiva, and along the lid margin are the sweat glands of Moll. 相似文献