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Gymnodinium bloom events are of concern, since they produce toxins, which have unfavorable consequences to marine ecosystems, human health and the economy. This report describes the physico-chemical conditions that were present during the algal bloom event on May 2010 in Bahía Manzanillo and Bahía Santiago, Colima, Mexico. For this, seawater nutrient analysis, phytoplankton counts, identification, and toxicity tests were undertaken. Nutrients in seawater were determined using colorimetric techniques, the higher concentrations (8.88 microM DIN, 0.78 microM PO4 and 24.34 microM SiO2) were related with upwelling waters that promoted the algal bloom that began after registering the year lowest sea-surface temperature, favoring the rapid growth of G. catenatum (up to 1.02 x 10(7) cells/L). Phytoplankton counting was carried out using sedimentation chambers and cells enumerated on appropriated area. The bloom persisted in the bays for approximately two weeks and was associated with toxicity (determined with HPLC) in local oysters (1525.8 microg STXeq/100g), and in phytoplankton (10.9 pg STXeq/cells) samples. Strong variations in cell toxicity (1.4 to 10.9pg STXeq/cells), most likely reflected the availability of inorganic nutrients. The toxin profile of the phytoplankton samples consisted of 11 toxins and resembled those recorded for several strains of G. catenatum isolated from other coastal areas of Mexico.  相似文献   

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The present paper reports a laboratory investigation performed between the years of 2000 and 2002 to study a virological surveillance program introduced in the state of Piauí to support an epidemiological survey of the disease. Dengue virus type 3 (DENV-3) existence in the state was detected in May 2002 when a high number of dengue cases due to DENV-1 and DENV-2 were reported. An assessment on the population knowledge about the disease and its transmission showed that almost 50% of the population were still unaware of the epidemiological features of dengue.  相似文献   

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Liposomal amphotericin B is a lipid formulation of the antifungal drug amphotericin B with some distinguishing characteristics in its pharmacological behavior that entail some clinical differences of great interest. The significant improvement in the systemic and renal tolerability is one of them. This fact is related to the great stability of the liposome, promoted by its negative charge, the presence of cholesterol and the remarkable thermo-stability of the remaining lipids that compose it. In this situation, amphotericin B seems to be released from the liposome not spontaneously but when the liposome binds to the ergosterol in the fungal cell membrane. For this reason, there is almost no free amphotericin B in plasma or tissues, although it seems that its availability is greater when there is fungal infection. As a consequence, when the pharmacokinetic behavior is studied, the concentration and availability of liposomal amphotericin B are very high, and its volume of distribution is reduced in comparison with the other formulations.  相似文献   

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A ten-year birch pollen record for Reykjavík, Iceland, has been analyzed with respect to fluctuations in the annual pollen sum, the starting date, and the duration of the birch pollen season. A three-year cycle is observed for the annual birch pollen sum, which could be of value in predicting the severity of the next birch pollen season. The annual birch pollen sum is regressed on six climatic variables, only one of which turned out to be statistically significant. The number of days with temperatures above +7.5°C in the year of inflorescence initiation shows a significant correlation with the annual birch pollen sum of the following flowering year (P =0.009). For the starting date of the birch pollen season the accumulated thermal sum on May 15 is shown to have the best predictive value, estimating it to within one week. The mean duration of the birch pollen season in southwestern Iceland is 17 days, starting May 29 and ending June 14.  相似文献   

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The fossil-rich site within the Albian Escucha Formation in the Oliete Sub-basin, located in the Northeast of Spain, has provided a great abundance of impressions, including leave remains and seed cones of Coniferales (Sphenolepis kurriana, Sphenolepis sternbergiana, Elatides curvifolia, Brachyphyllum sp. and Geinitzia sp. cf. G. rigida), leaves of Caytoniales (Sagenopteris elliptica), Ginkgoales (Ginkgoites pluripartita, and Sphenobaiera sp. cf. S. longifolia), Bennettitales (Ptilophyllum sp. cf. P. pecten and aff. Zamites sp.), Cycadales (Nilssonia tenuinervis and Ctenozamites with entire and denticulate pinnae margins), Czekanowskiales, and reproductive structures of Gnetales. The gymnosperm remains are fairly abundant in the upper member, built up of sediments deposited in fluvial and swamp environments without marine influence. The different gymnosperm associations in this outcrop indicate a wide variety of environments in a subtropical climate, and a mixture of North American and European taxa in the Iberian plate during the Middle Albian.  相似文献   

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Nearly 230 species of biting midges have been recorded or described from Argentina; 38 of them are known from the Buenos Aires province and only one is cited from Martín García Island. This paper presents the results raised from six collecting trips which took place on the island during spring 2005, summer 2006 and autumn 2009. Diverse sampling sites including permanent and temporary aquatic environments were chosen, most of the ten sampling sites were ponds of diverse origin, some of these environments were covered with floating vegetation as Lemna gibba, Lemna minuscule, Salvinia biloba, Salvinia minima, Azolla filiculoides, Limnobium laevigatum, Pistia stratiotes, Spirodela intermedia, Wolffiella oblonga and Wolffia columbiana. Other sites were placed in urban and suburban areas. Adults were collected with sweep nets at sunrise and sunset and with light traps at intervals of four to five hours at night, depending on electricity availability on the island. Larvae and pupae were collected with different implements depending on characteristics of each surveyed aquatic habitat. In free standing water, they were captured with small sieves or hand pipettes and micropipettes, flotation techniques were utilized for sampling vegetated areas, free and rooted floating hydrophytes were extracted for removing insects among them. Thirteen species of Ceratopogonidae were collected, three of Atrichopogon Kieffer, three of Forcipomyia Meigen, two of Dasyhelea Kieffer, four of Culicoides Latreille, and one of Bezzia Kieffer, all representing new records from the island.  相似文献   

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Background and objectives1) Nutritional assessment of the diet followed by patients with metabolic syndrome, and 2) biochemical analysis of the oxidation-reduction level in patients with metabolic syndrome.Material and methodsA cross-sectional study was conducted in patients with metabolic syndrome in Murcia. Fifty-three patients, 33 with and 20 without (control group) metabolic syndrome, were selected. The intervention consisted of completion of a recall survey and a test to nutritionally assess dietary intake. Anthropometric and laboratory variables, including those related to antioxidant activity, were also tested.ResultsAntioxidant activity was within normal limits in both groups (1.7 ± 0.2 mmol/L in the control group and 1.8 ± 0.1 mmol/L in the metabolic syndrome group) (NS). Superoxide dismutase levels were not significantly different between the groups. Mean glutathione reductase levels (U/L) were higher in the control group as compared to patients with metabolic syndrome (P < .05). As regards oxidative stress biomarkers, mean isoprostane levels were higher in the control group (4.9 ± 6.2 ng/mL) than in metabolic syndrome patients (3.5 ± 3.9 ng/mL) (P < .05). Oxidized LDL values tended to be higher in metabolic syndrome patients (96 ± 23.2 U/L) as compared to the control group (86.2 ± 17.3  U/L), but differences were not significant.ConclusionsThere is a trend to a poorer nutritional and biochemical profile in patients with metabolic syndrome, who also tend to have a greater degree of oxidative stress.  相似文献   

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Abstract

Thriving populations of the Spiny Oyster Spondylus spinosus Schreibers, 1793, an Indo-Pacific bivalve, are reported from off the Mediterranean coast of Israel. The taxonomy and nomenclature of this new Lessepsian migrant are briefly discussed. The polymorphism of the Mediterranean specimens is discussed. Their habitat is described, and the epibionts and predators in the Mediterranean are enumerated.  相似文献   

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Aimsto study fear of falling (FOF) syndrome at 1 year in a population of elderly individuals referred to a specific outpatient clinic for dizziness, falls and syncope. To analyse which variables gathered at the beginning of the study were related with FOF at that time and 1 year later.Methodsa prospective cohort study was performed from April 2000 to December 2001. Sixty-six elderly individuals referred to a specific outpatient clinic for dizziness, falls and syncope were classified in a group with FOF (n = 31) or a group without FOF (n = 35). Patients without all the tests and those lost to follow-up were excluded. The protocol included medical history, physical examination, tilt test and routine or specific complementary tests, when deemed necessary. FOF was determined through the direct question: Are you afraid of falling?ResultsFOF disappeared in 14 patients (45.2%) who had this syndrome at the beginning of the study and developed in five patients (14.3%) who did not (p = 0.06). After multivariate analyses, the variables associated with FOF at the beginning of the study were: taking benzodiazepines, recurrent dizziness, higher blood urea levels and a drop in systolic blood pressure with upright position. The variables significantly associated with fear of falling 1 year later were: angiotensin-converting enzyme inhibitors, positive Hallpike's manoeuvre and a drop in diastolic blood pressure with the head-up-tilt test. The model also included taking benzodiazepines and symptom reproduction with movement of the neck.Conclusionsat 1 year, FOF syndrome decreased in nearly half the patients who had this syndrome at the beginning of the study but developed in other patients without this syndrome at that time. No association was found with falls at the beginning or end of the study. At 1 year of follow-up, FOF was associated with intake of certain medications and data from the tilt test.  相似文献   

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In a study of the yeasts associated with alpechín two new species and one new variety were found. These are described asTorulopsis salmanticensis, Saccharomyces norbensis andPichia vini, var.melibiosi. In addition to the physiological properties usually utilized for characterization of yeasts the following properties were also examined: occurrence of -fructosidase, utilization of lysine as a source of nitrogen, utilization of a mixture of amino acids as sole source of carbon, and resistance to actidione.  相似文献   

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