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121.
The largest semi-enclosed basin in the world, the Mediterranean Sea, is characterized by high biodiversity and heavy human pressure on the coastal system. The Strait of Sicily (SoS) represents the boundary between western and eastern Mediterranean sub-regions and is an important biodiversity hot spot. Given its ecotonal nature and it being a “crossroad” for the westward expansion of warm-temperate and tropical species from the Levantin basin, the SoS is likely to play a key role in future climate change related biodiversity changes within the Mediterranean. The complexity of the SoS ecosystem, characterized by wider shallow detritic and rocky banks on the continental shelf hosting large biodiverse communities, and peculiar circulation pattern, promotes species diversity and abundance. In addition, the deep-sea is characterized by the occurrence of extremely vulnerable habitats, such as deep-water communities of scleractinian corals, antipatharians, gorgonians, and red coral. We review the current knowledge on the main characteristics of the north sector of the SoS ecosystem. The SoS ecosystem is increasingly threatened by expanding anthropogenic pressures in the area and specific conservation measures should be implemented on a national and international level to protect the relevant and vulnerable habitats.  相似文献   
122.
Genetic diversity and structure of Pseudoplatystoma corruscans and P. reticulatum, large migratory South America catfishes, where overfishing and the construction of numerous dams in their feeding and reproducing areas are affecting their migratory processes negatively, were studied using microsatellites in samples from Paraguay (that comprises the Pantanal biome), and the upper and lower Paraná Basins. Genetic diversity was in accordance to that observed for other large migratory fishes, but the most geographically isolated populations of P. reticulatum and those P. corruscans subject to anthropogenic effects (stocking and dams) showed lower genetic diversity and evidences of bottlenecks compatible with low effective population size. Pseudoplatystoma reticulatum presented subtle genetic differentiation within the Paraguay area, especially between the edges of its distribution. Pseudoplatystoma corruscans, in this same area, presented a quite homogeneous but significant genetic break between the Paraguay and upper Paraná populations, apparently resulting from natural and historical isolation between the basins until recently. These data demonstrates that, although these Pseudoplatystoma spp. are abundant in the Pantanal area, anthropogenic events are leading to negative effects on their populations, particularly in the upper Paraná Basin. Genetic differentiation observed along each species distribution demands conservation actions to preserve each population's biodiversity. These results represent important genetic information using new microsatellite markers and the first genetic study of P. reticulatum covering this area of its native distribution. Data may also contribute to a better understanding of species migration patterns and to be used as a baseline for proper management.  相似文献   
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The aim of the present study is to analyze the morphologic changes occurring along the period of a woman's life thatareknown as climacterium. Our sample consists of 648 women from different provinces of Cuba, but who lived in Havana for at least 15 years. Morphological variables such as height, weight, biliocristal and biachromial diameters and six subcutaneous fat skinfolds were measured. With regard to the menopausic condition, the sample was divided into three subpopulations: premenopausic, naturally menopausic and surgically menopausic (when the two ovaries had been removed). Age at menopause was calculated by both the “retrospective” (49.45±0.49) and “status quo” (48.83±0.02) methods. The results obtained point towards morphological differences between pre- and postmenopausic women. We observed greater accumulations of fatty tissue in the suprailiac regions of postmenopausal females. Lean body mass represents a bigger fraction of the total body weight in women who are still menstruating. In the case of surgically menopausic women, they are at a mid-distance between the premenopausic and naturally menopausic subpopulations. A discriminant analysis was carried out which confirmed the results previously observed. From this analysis it appeared the body mass index and the subcutaneous skinfolds are the variables that discriminante, that is, separate, the three subsamples.  相似文献   
125.
BackgroundHealthcare systems in dengue-endemic countries are often overburdened due to the high number of patients hospitalized according to dengue management guidelines. We systematically evaluated clinical outcomes in a large cohort of patients hospitalized with acute dengue to support triaging of patients to ambulatory versus inpatient management in the future.Methods/Principal findingsFrom June 2017- December 2018, we conducted surveillance among children and adults with fever within the prior 7 days who were hospitalized at the largest tertiary-care (1,800 bed) hospital in the Southern Province, Sri Lanka. Patients who developed platelet count ≤100,000/μL (threshold for hospital admission in Sri Lanka) and who met at least two clinical criteria consistent with dengue were eligible for enrollment. We confirmed acute dengue by testing sera collected at enrollment for dengue NS1 antigen or IgM antibodies. We defined primary outcomes as per the 1997 and 2009 World Health Organization (WHO) classification criteria: dengue hemorrhagic fever (DHF; WHO 1997), dengue shock syndrome (DSS; WHO 1997), and severe dengue (WHO 2009). Overall, 1064 patients were confirmed as having acute dengue: 318 (17.4%) by NS1 rapid antigen testing and 746 (40.7%) by IgM antibody testing. Of these 1064 patients, 994 (93.4%) were adults ≥18 years and 704 (66.2%) were male. The majority (56, 80%) of children and more than half of adults (544, 54.7%) developed DHF during hospitalization, while 6 (8.6%) children and 22 (2.2%) adults developed DSS. Overall, 10 (14.3%) children and 113 (11.4%) adults developed severe dengue. A total of 2 (0.2%) patients died during hospitalization.ConclusionsOne-half of patients hospitalized with acute dengue progressed to develop DHF and a very small number developed DSS or severe dengue. Developing an algorithm for triaging patients to ambulatory versus inpatient management should be the future goal to optimize utilization of healthcare resources in dengue-endemic countries.  相似文献   
126.
The invasive freshwater snail Tarebia granifera (Lamarck, 1822) was first reported in South Africa in 1999 and it has become widespread across the country, with some evidence to suggest that it reduces benthic macroinvertebrate biodiversity. The current study aimed to identify the primary abiotic drivers behind abundance patterns of T. granifera, by comparing the current abundance of the snail in three different regions, and at three depths, of the highly modified Nseleni River in KwaZulu-Natal, South Africa. Tarebia granifera was well established throughout the Nseleni River system, with an overall preference for shallow waters and seasonal temporal patterns of abundance. Although it is uncertain what the ecological impacts of the snail in this system are, its high abundances suggest that it should be controlled where possible and prevented from invading other systems in the region.  相似文献   
127.
Herein we report investigations into the p38alpha MAP kinase activity of trisubstituted imidazoles that led to the identification of compounds possessing highly potent in vivo activity. The SAR of a novel series of imidazopyridines is demonstrated as well, resulting in compounds possessing cellular potency and enhanced in vivo activity in the rat collagen-induced arthritis model of chronic inflammation.  相似文献   
128.
From the structure of 3,3-dimethyl-3H-benzofuro[3,2-f][1]-benzopyran, a selective in vitro inhibitor of mycobacterial growth, we have undertaken a structure-activity relationship investigation. We wish to report here our results on the use of [2+3] cycloadditions between 2-formylbenzoquinone and various enol derivatives to give various 4-formyl-5-hydroxy benzofurans. In the next step, an ytterbium triflate-catalysed reaction with 2-methylpropene allowed the preparation of various original furo[3,2-f]chromenes derivatives. Their biological evaluation on the growth of Mycobacterium smegmatis as well as Mycobacterium tuberculosis pointed out that some analogues were four times more active than the initial hit.  相似文献   
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Many bioprocesses depend on the effective formation of a biofilm on a solid support. In the present study, three different surface treatments (sandblasting, pure‐O2 plasma, and He–O2 plasma treatments) were conducted on polypropylene (PP) Pall rings used as a support in biotrickling filters for air pollution control. The intent was to modify the ring surface and/or electrochemical properties in order to possibly improve cell adhesion, wetting properties, and possibly reduce the start‐up time and increase the performance of the biotrickling filters. The surface treatments were found to generally increase the hydrophilicity and the zeta potential of the surfaces. However, the startup and performance of lab‐scale biotrickling filters packed with treated Pall rings were not significantly different than the control with untreated rings. Cell and colloid deposition experiments conducted in flow cells showed that the treated surfaces and the hydrodynamic conditions were not favorable for cell deposition indicating that there could be significant opportunities for improving packings used in environmental bioprocess applications. Biotechnol. Bioeng. 2009;103: 1060–1067. © 2009 Wiley Periodicals, Inc.  相似文献   
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