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71.
We studied the vertical distribution of sulfite-reducing clostridia in the sediment of a Spanish high-mountain lagoon (Laguna Grande de Gredos, central Spain), with optimal sediment characteristics (temperature < 20 degrees C) to maintain spores without growing. This allowed us to assess the original numbers of sulfite-reducing clostridia endospores settled, without postdepositional growing. Sulfite-reducing clostridia are normal inhabitants of the intestinal microbiota of humans and other mammals. These microorganisms may form endospores, which allow the bacteria to survive in almost any habitat, either terrestrial or aquatic, waiting for favorable conditions for growth. Sulfite-reducing clostridia could be suitable indicators of past human pollution because they have a great longevity in natural habitats and they cannot multiply at temperatures below 20 degrees C or in the presence of O2. We found a great increase in the numbers of clostridia (expressed as colony-forming units per gram [CFU/g] of dry weight of sediment) since the 1970s, which reflects the rise of human pressure caused by the practice of outdoor activities. Clostridia CFU/g rose dramatically after the faulty operation of the depuration system of a mountain refuge built close to the lagoon. We compared the vertical distribution of clostridia CFU/g from Laguna Grande sediments with those from a neighbor lagoon (Laguna Cimera), which showed less tourist pressure and no direct disposal of sewage. Finally, we agree with the usefulness of the numbers of sulfite-reducing clostridia as indicators of past pollution. 相似文献
72.
Marmi J Casanovas-Vilar I Robles JM Moyà-Solà S Alba DM 《Journal of human evolution》2012,62(3):412-423
The early Vallesian site of Can Llobateres 1 (Vallès-Penedès Basin, Catalonia, Spain) is one of the richest localities of the European Late Miocene, having yielded the most complete remains of the fossil great ape Hispanopithecus laietanus (Primates: Hominidae). Fossil plant remains had been previously reported from this site but mostly remained unpublished. Here we describe an assemblage of plant megaremains recovered in 2010, which provides valuable paleoenvironmental data. This assemblage consists of a mixture of parautochthonous and allochthonous detached organs (leaves, stems, reproductive structures) deposited in marshy areas. The source vegetation mainly consisted of abundant reeds, palms, evergreen laurels and figs that probably grew in or near the marsh boundaries or nearby riparian forests. This environmental picture is consistent with the mammalian fauna, which shows the prevalence of humid forested environments, although somewhat more open woodlands might have been present away from the wet areas. The occurrence of mega-mesothermal taxa, together with the absence of deciduous elements, is consistent with a subtropical to warm-temperate climate. Within this mosaic environment, H. laietanus would have preferred the more humid and forested habitats, which probably were still quite common in the Vallès-Penedès during the early Vallesian. Such habitats would have provided a continuous ripe fruit supply throughout the year to these frugivorous great apes. Paleobotanical data from older sites of the same area and nearby basins show that the zonal vegetation was a warm-temperate mixed forest defined by evergreen laurels, together with leguminous trees and shrubs as well as a significant proportion of deciduous elements. Tropical and subtropical taxa would have been restricted to humid areas in the lowlands. From the late Vallesian onwards, many of these taxa disappeared from the Vallès-Penedès, whereas deciduous trees became dominant in the forested areas and wetlands, thus likely having driven Hispanopithecus to extinction in the study area. 相似文献
73.
Twelve polymorphic microsatellite loci were developed for Dendrocopos medius. Polymorphism was assessed for 27 individuals from the southwesternmost population of this woodpecker species. The number of alleles per locus ranged from three to seven, with observed heterozygosity values from 0.444 to 0.852. Genotypic frequencies conformed to Hardy-Weinberg equilibrium, and no evidence for linkage disequilibrium was observed. Multilocus genotypes resulting from this set of markers will be useful to determine genetic diversity and differentiation within and among habitat patches inhabited by D. medius. Three of the loci were polymorphic for Picoides articus. 相似文献
74.
Clinical behaviour of prostatic specific antigen and prostatic acid phosphatase: a comparative study
J Morote Robles A Ruibal Morell J A De Torres Mateos A Soler Roselló 《The International journal of biological markers》1989,4(2):87-94
We assayed prostatic specific antigen (PSA) and prostatic acid phosphatase (PAP) serum levels in 1383 patients using a double antibody radioimmunoassay (RIA) I125. Establishing the upper normal limit in 10 ng/ml PSA and 2.5 ng/ml for PAP, the false positive results were only 1.9 and 5.1 percent in men with non-prostatic benign or malignant pathology and respectively 0 and 2.2 percent in women. We detected false positive levels for these two tumoral markers in 3.5 and 4.7 percent of patients with non-complicated benign prostatic hypertrophy, 64.8 and 19.2 percent in complicated benign prostatic hypertrophy, 24 and 16 percent in acute prostatitis and 3.3 percent in chronic prostatitis. The sensitivity in patients with prostate cancer was 87.2 percent for PSA and 64.1 percent for PAP, and there was a better correlation with PSA than PAP for tumoral spread and histological grading. Finally, clinical efficacy was higher with PSA and was no better when both markers were assayed. 相似文献
75.
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
76.
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
77.
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
78.
Downstream processing of algal polyunsaturated fatty acids 总被引:8,自引:0,他引:8
Robles Medina A Molina Grima E Giménez Giménez A Ibañez González MJ 《Biotechnology advances》1998,16(3):517-580
Little information exists on recovering polyunsaturated fatty acids from microalgae; however, methods for concentration and purification of PUFAs from fish oil have been extensively reported. This review examines recovery and purification of microalgae derived PUFAs, but techniques developed for use with fish oil are also reviewed as being potentially useful for concentration and purification from microalgae. The two main techniques for concentrating and purifying-urea fractionation and high performance liquid chromatography-are discussed in depth and attention is focused on the process developed by the authors for obtaining highly pure PUFA. Other potentially useful techniques, such as supercritical fluid extraction and lipase-catalyzed processing are detailed. 相似文献
79.
80.