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61.
Some epidemiologic, diagnostic and immunologic aspects of 93 (75 males and 18 women) cases of cryptococcosis (CRY) associated with AIDS, hospitalized in the Muñiz Hospital (MH) in Buenos Aires during 1994, were retrospectively studied. The median age (MA) of the patients under study was 28 years (17–49 y); 30 (17–49) y for males and 23 (22–34) y for women. Intravenous drug addiction (34% of patients) and homo/bisexuality in men (17%) were the most frequent risk factors for HIV infection. The MA of these groups were 27.5 (17–41) y and 34 (25–41) y, respectively. Microscopic CSF examination with India ink and the blood cultures (lysis-centrifugation) achieved the diagnosis of CRY in 67 (72%) and 16 (17%) patients, respectively. At diagnosis, the median titers for Cryptococcus neoformans capsular antigen were 1/1,000, 1/100 and 1/1 in serum, CSF and urine, respectively. Sixty five strains of C. neoformans were insolated from clinical samples; all were identified at variety neoformans employing the culture medium proposed by Salkin &; Hurd and the D-proline assimilation test. At diagnosis, CD4+lymphocytes counts were <50/μl in 46 patients (83.63%), and were between 51 and 200/μl in 9 (16.4%). The CD4+CD8+ ratio was <1 in all patients. Most patients were born (83%) and lived at diagnosis (96%) in Buenos Aires (Bs As) city, Bs As outskirts towns and cities located in Bs As province. 相似文献
62.
Bava AJ Robles AM Negroni R Arechavala A Bianchi M 《Revista iberoamericana de micología》1997,14(3):111-114
Some epidemiological characteristics of 253 cases of cryptococcosis (CRY) diagnosed between 1981 and 1993 in the Mu?iz Hospital (MH) of Buenos Aires City, were studied. The incidence of CRY associated with AIDS (CRY+AIDS) in the MH during 1983-1993, could be divided into 3 periods: between 1983 and 1988 1-3 cases a year were diagnosed; during 1989-91, the number of cases dopubled annually and in 1992-93 the annual increment was lower. CRY associated with predisposing causes other than AIDS (CRY+non AIDS) exhibited an annual incidence of 0-3 cases during the whole period studied. CRY was more frequent in males (86%). The difference between sexes was more evident in CRY+AIDS patients (88% males) than CRY+non AIDS ones (65% males). The median age (MA) of the studied population was 28 (range 10-71) years; 27 (10-48) in women and 29 (17-71) in men. CRY+AIDS and CRY+non AIDS patients exhibited a MA of 29 (17-51) and 40 years (10-71), respectively. AIDS was the predisposing factor in 92% of patients; 65% of them were intravenous drug abusers and 22% homosexual males, with a MA of 27 (17-40) and 33 (23-55) years, respectively. Cryptococcus neoformans var. neoformans was isolated from all CRY+AIDS and 79% of CRY+non AIDS patients and the gattii variety (Serotype B) produced 4 (21%) cases of CRY+non AIDS. 相似文献
63.
Jung JA Jhang E. John Staba Jung Yun Kim 《In vitro cellular & developmental biology. Plant》1974,9(4):253-259
Summary Roots, stems, or leaves of American (Panax quinquefolium) and Korean (Panax ginsing) ginseng were grown as callus or supension tissue cultures. Tissue cultures ofP. ginseng would occasionally form plantlets. The fundamental chemical composition, inorganic analysis, and saponin (panaquilin) content
of American and Korean ginseng plants and tissue cultures were determined. The crude saponin content is very similar to, but
approximately one-half (1.3%, fresh weight) of that present in ginseng roots. Two-dimensional thin layer chromatographic analysis
revealed minor differences in the panaquilins present in American and Korean ginseng tissue cultures. The sapogenin, panaxadiol,
was isolated from Korean ginseng callus. 相似文献
64.
65.
Preparation of deacylated phosphoglycerides 总被引:1,自引:0,他引:1
O-(sn-glycero-3-phosphoryl) ethanolamine and O-(sn-glycero-3-phosphoryl) choline can conveniently be isolated on a preparative scale from egg-yolk powder or soybean phospholipids by the following procedure:
- 1.
- 1.|Mild-alkaline methanolysis of the lipids. 相似文献
66.
Morphology of the retina in deep‐water fish Nezumia sclerorhynchus (Valenciennes, 1838) (Gadiformes: Macrouridae)
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Magdalena García Sabina Tomás Maria Laura Robles Alfonso Ramos Yolanda Segovia 《Acta zoologica》2018,99(1):87-92
Using light microscopy, we examined the retina of benthopelagic fish Nezumia sclerorhynchus. Although the retina is typical of other vertebrates, having three nuclear and two synaptic layers, it presents some features associated with the animal's deep‐sea habitat. A stratum argenteum containing iridescent crystals is located in the choroid. The pigment cell layer shows bulky cells filled with melanin granules but without the typical apical processes. The visual cells, consisting of a big population of rods, are arranged in several banks. No cones were observed. The outer segments are very long and cylindrical, and the inner segments are constituted by a small ellipsoid at the proximal end. The outer nuclear layer contains several rows of oval nuclei, and the spherules in the outer plexiform layer have less regular outlines than nuclei. The inner retina is characterized by very large horizontal cells, and presumable bipolar and amacrine cells separated by large spaces that are occupied by neuronal processes. Finally, the low density of ganglion cells produces a thin nerve fibre layer. The results of this study suggest that the retina of Nezumia sclerorhyncus exhibits high visual sensitivity and that vision is a sense that plays an important role in its behaviour. 相似文献
67.
JA Nboyine S Boyer D Saville MJ Smith SD Wratten 《New Zealand journal of zoology.》2016,43(4):336-350
The endemic New Zealand ground wētā (Hemiandrus sp. ‘promontorius’) has a Naturally Uncommon conservation status. This is because of the paucity of information on its density and distribution. Here, the biology, density and distribution of a population of this wētā found in and around vineyards in the Awatere Valley, Marlborough was studied. Wētā density was assessed in vineyards, paddocks and shrublands in this valley. Soil moisture, penetration resistance, pH and organic matter were recorded at locations with and without wētā. Wētā density in vineyards was significantly higher than in either paddocks or shrub habitats. In vineyards, the density of this insect was significantly higher under-vines than in the inter-rows. Higher numbers of this wētā were found in moist soils that required lower force to burrow. Females laid an average of 55 eggs between March and April, which hatched in September. These findings highlight the intersection between agriculture and conservation. 相似文献
68.
Distinguishing morphologically cryptic taxa, by definition, requires genetic data such as DNA sequences. However, DNA sequences may not be obtained easily for taxa from remote sites. Here we provide the details of a high-resolution melt-curve-based method using taxon-specific primers that can distinguish two taxa of Adélie penguins, and that will be usable in Antarctica when combined with some of the newly developed field-deployable thermal cyclers. We suggest that the wider adoption of field-deployable polymerase-chain-reaction-based techniques will enable faster assignation of haplotype to individuals in situ, and so allow the targeting of observations and sample collection to specimens relevant to the research question. Targeting individuals will also reduce the need to repeatedly handle animals and reduce the time and travel required to complete field work. 相似文献
69.
J. Serrano-Cartagena P. Robles M. R. Ponce J. L. Micol 《Molecular & general genetics : MGG》1999,261(4-5):725-739
Although a vast inventory of morphological mutants of Arabidopsis thaliana is available, only some have been used for genetic studies of leaf development. Such is the case with the Arabidopsis Information Service (AIS) Form Mutants collection, assembled by A. R. Kranz and currently stored at the Nottingham Arabidopsis Stock Centre, which includes a large number of mutant lines, most of which have been little studied. With the aim of contributing
to the genetic dissection of leaf ontogeny, we have subjected 57 mutant lines isolated by others to genetic analysis; 47 of
which were from the AIS collection. These are characterized by vegetative leaves of abnormal shape or size, and were chosen
as candidates for mutations in genes required for leaf morphogenesis. The mutant phenotypes studied were shown to be inherited
as single recessive Mendelian traits and were classified into 10 phenotypic classes. These mutant strains were found to fall
into 37 complementation groups, 7 of which corresponded to known genes. Results of the phenotypic analysis and data on the
genetic interactions of these mutants are presented, and their possible developmental defects discussed.
Received: 28 October 1998 / Accepted: 21 February 1999 相似文献
70.