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71.
Pseudonemesia tabiskey sp. nov. is described from an Andean Forest in Trujillo, Venezuela. The new species is the third for the genus and differs from the other two species by the presence of one short and apically rounded modified seta on the retrolateral distal portion of the male tibia I and clavate setae on the dorsal and lateral sides of abdomen in both sexes. A new diagnosis is given to Pseudonemesia and new morphological data based on scanning electron microscopy for the Microstigmatinae are presented. The presence of posterior median spinnerets in Pseudonemesia is discussed.  相似文献   
72.
73.
PHD2 serves as an oxygen sensor that rescues blood supply by regulating vessel formation and shape in case of oxygen shortage. However, it is unknown whether PHD2 can influence arteriogenesis. Here we studied the role of PHD2 in collateral artery growth by using hindlimb ischaemia as a model, a process that compensates for the lack of blood flow in case of major arterial occlusion. We show that Phd2 (also known as Egln1) haplodeficient (Phd2(+/-)) mice displayed preformed collateral arteries that preserved limb perfusion and prevented tissue necrosis in ischaemia. Improved arteriogenesis in Phd2(+/-) mice was due to an expansion of tissue-resident, M2-like macrophages and their increased release of arteriogenic factors, leading to enhanced smooth muscle cell (SMC) recruitment and growth. Both chronic and acute deletion of one Phd2 allele in macrophages was sufficient to skew their polarization towards a pro-arteriogenic phenotype. Mechanistically, collateral vessel preconditioning relied on the activation of canonical NF-κB pathway in Phd2(+/-) macrophages. These results unravel how PHD2 regulates arteriogenesis and artery homeostasis by controlling a specific differentiation state in macrophages and suggest new treatment options for ischaemic disorders.  相似文献   
74.
ABSTRACT

We introduce herein Lanayrella gen. nov. to accommodate two Acteonidae species that have proven resistant to stable classification: Tornatella vagabunda Mabille, 1885 and Acteon ringei Strebel, 1905. The new genus is diagnosed by a protoconch fully immersed within the shell and a platform-like columellar region of the aperture, which bears a strong and sharp adapical fold. Both species are restricted to Tierra del Fuego: Lanayrella vagabunda comb. nov. on the Chilean part and Lanayrella ringei comb. nov. on the Argentinean side.

http://www.zoobank.org/urn:lsid:zoobank.org:act:37EA6720-0E0E-4C81-A2A8-F85FA2E53929  相似文献   
75.
Schimke immuno-osseous dysplasia (SIOD, MIM 242900) is an autosomal-recessive pleiotropic disorder with the diagnostic features of spondyloepiphyseal dysplasia, renal dysfunction and T-cell immunodeficiency. Using genome-wide linkage mapping and a positional candidate approach, we determined that mutations in SMARCAL1 (SWI/SNF2-related, matrix-associated, actin-dependent regulator of chromatin, subfamily a-like 1), are responsible for SIOD. Through analysis of data from persons with SIOD in 26 unrelated families, we observed that affected individuals from 13 of 23 families with severe disease had two alleles with nonsense, frameshift or splicing mutations, whereas affected individuals from 3 of 3 families with milder disease had a missense mutation on each allele. These observations indicate that some missense mutations allow retention of partial SMARCAL1 function and thus cause milder disease.  相似文献   
76.
Fatty acid anilides, the major xenobiotic found in the cooking oils responsible for the Spanish toxic oil syndrome, are immunogenic for rabbits as ascertained by a skin test reaction, the characterization of specific antibodies against anilides and the immunofluorescent detection of 'anilide dependent antigens' in tissue slices from treated animals.  相似文献   
77.
The worldwide leaf economics spectrum   总被引:48,自引:0,他引:48  
Bringing together leaf trait data spanning 2,548 species and 175 sites we describe, for the first time at global scale, a universal spectrum of leaf economics consisting of key chemical, structural and physiological properties. The spectrum runs from quick to slow return on investments of nutrients and dry mass in leaves, and operates largely independently of growth form, plant functional type or biome. Categories along the spectrum would, in general, describe leaf economic variation at the global scale better than plant functional types, because functional types overlap substantially in their leaf traits. Overall, modulation of leaf traits and trait relationships by climate is surprisingly modest, although some striking and significant patterns can be seen. Reliable quantification of the leaf economics spectrum and its interaction with climate will prove valuable for modelling nutrient fluxes and vegetation boundaries under changing land-use and climate.  相似文献   
78.
Systems dialectics is conceived as the integration of two convergent and complementary lines of thinking; one, methodological, the other one, philosophical. The methodological approach attempts to understand the same system, or systems, from static, dynamic, and dialectical perspectives. Systems dynamics considers systems from the viewpoint of homeostasis or dynamic equilibria. Systems dialectics tries to explain mutation-sudden structural and functional change-in nature and society. The modern philosophical trend follows the line of dialectical idealism (Hegel); dialectical materialism (Engels, Marx); and the French scientific dialectics movement, which made a first attempt to synthesize both approaches. Systemic dialectics tries to understand these approaches from a global perspective, as complementary viewpoints. A practical application of systems dialectics would be to test in the real world its global viewpoints in order to transform conflicting situations by applying the new paradigm to the integrated development of individuals and groups.  相似文献   
79.
We analyzed the prevalence and intensity of chewing lice on two neotropical species of Turdus and identified morphological parameters of birds influencing louse population dynamics. The study was conducted in southernmost Rio Grande do Sul state (RS), Brazil, between July 2009 and June 2010. Chewing lice were collected by dust-ruffling. The prevalence of chewing lice on both species of Turdus was high. Chewing lice from both species of Turdus exhibit similar composition and distribution patterns. However, chewing lice were more abundant on Turdus rufiventris, whereas species richness was higher on Turdus amaurochalinus. Myrsidea and Brueelia were the most prevalent and abundant genera on both host species in all seasons of the year. A predominance of chewing louse females and adults was observed. Aggregated distributions were observed. Body length was the only morphological parameter correlated with louse abundance, suggesting that specimens with a larger body have a higher abundance of lice.  相似文献   
80.
Transmissible spongiform encephalopathies (TSEs) are neurodegenerative diseases associated with progressive oligo- and multimerization of the prion protein (PrPC), its conformational conversion, aggregation and precipitation. We recently proposed that PrPC serves as a cell surface scaffold protein for a variety of signaling modules, the effects of which translate into wide-range functional consequences. Here we review evidence for allosteric functions of PrPC, which constitute a common property of scaffold proteins. The available data suggest that allosteric effects among PrPC and its partners are involved in the assembly of multi-component signaling modules at the cell surface, impose upon both physiological and pathological conformational responses of PrPC, and that allosteric dysfunction of PrPC has the potential to entail progressive signal corruption. These properties may be germane both to physiological roles of PrPC, as well as to the pathogenesis of the TSEs and other degenerative/non-communicable diseases.  相似文献   
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