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81.
Albert Ruhí Eglantine Chappuis Daniel Escoriza Miquel Jover Jordi Sala Dani Boix Stéphanie Gascón Esperança Gacia 《Hydrobiologia》2014,723(1):25-39
Climate characteristics appear to play a key role in filtering organisms based on their biological traits. If this trait filtering by climate indeed occurs, it should have effects on the composition, dynamics, taxonomic relatedness and co-occurrence patterns of local assemblages, regardless of the taxonomic group considered. This preliminary study aimed to assess the extent to which environmental variables might determine these patterns in local communities and to evaluate whether the ultimate cross-taxon congruence relationships are consistent across, or dependent on, the selected region. To this end, we studied the bryophyte, macrophyte, macroinvertebrate, and amphibian communities in two clusters of temporary wetlands on the NE Iberian Peninsula under mesothermal and semiarid climates. We observed effects of environmental filtering, with the communities differing between the climatic regions not only in their compositions but also in their dynamics and taxonomic relatedness patterns. Although the cross-taxon congruence in terms of species richness was high in the mesothermal climate, most of the congruent relationships were disrupted in the semiarid environment. Overall, because climate-dependent patterns appear to prevail over climate-consistent ones, we suggest that the use of surrogate taxa may be of limited value when aiming to assess wetland biodiversity across large areas. 相似文献
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Determination of the molecular architecture of synapses requires nanoscopic image resolution and specific molecular recognition, a task that has so far defied many conventional imaging approaches. Here, we present a superresolution fluorescence imaging method to visualize the molecular architecture of synapses in the brain. Using multicolor, three-dimensional stochastic optical reconstruction microscopy, the distributions of synaptic proteins can be measured with nanometer precision. Furthermore, the wide-field, volumetric imaging method enables high-throughput, quantitative analysis of a large number of synapses from different brain regions. To demonstrate the capabilities of this approach, we have determined the organization of?ten protein components of the presynaptic active?zone and the postsynaptic density. Variations?in synapse morphology, neurotransmitter receptor composition, and receptor distribution were observed both among synapses and across different?brain regions. Combination with optogenetics further?allowed molecular events associated with synaptic plasticity to be resolved at the single-synapse level. 相似文献
84.
Purpose. Guidelines of the Dutch Association of General Practitioners (NHG) dictate the evaluation, treatment, and referral process of patients with stable chest pain syndromes (CPS). Adherence to this guideline was assessed in a consecutive group of patients referred to our hospital. Methods. We retrospectively studied the records of 296 subjects referred to our outpatient department in 2007 for evaluation of stable CPS. Referral letters were checked for completeness (past and present history, mentioning of risk factors for cardiovascular disease, physical examination, listing of medication) and used to judge adherence to the guideline. In a subset of patients, additional information regarding the referral process was gathered by telephone interview. Results. The referral letter was complete in only 67 patients (23%); items most often not reported were physical examination (63%) and cardiovascular risk factors (62%). Judging from the referral letter, 23 patients (8%) were evaluated in accordance with the NHG guideline prior to their referral. In patients in whom the final diagnosis of angina pectoris was made by the cardiologist, this was 20%. Seventy-nine patients were contacted by telephone after their work-up by the cardiologist; 36 of them (44%) reported being referred at their first visit to their primary physician, while 14 (18%) were referred at their own request. Conclusion: Prior to referral, only a minority of patients with stable CPS were evaluated and treated in accordance with NHG guidelines. Furthermore, their referral letter was often incomplete. (Neth Heart J 2010;18:178-82.) 相似文献
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Varda Levy-Litan Eli Hershkovitz Luba Avizov Dani Bercovich Esther Manor Sophia Buriakovsky James Goding 《American journal of human genetics》2010,86(2):273-278
Human disorders of phosphate (Pi) handling and hypophosphatemic rickets have been shown to result from mutations in PHEX, FGF23, and DMP1, presenting as X-linked recessive, autosomal-dominant, and autosomal-recessive patterns, respectively. We present the identification of an inactivating mutation in the ecto-nucleotide pyrophosphatase/phosphodiesterase 1 (ENPP1) gene causing autosomal-recessive hypophosphatemic rickets (ARHR) with phosphaturia by positional cloning. ENPP1 generates inorganic pyrophosphate (PPi), an essential physiologic inhibitor of calcification, and previously described inactivating mutations in this gene were shown to cause aberrant ectopic calcification disorders, whereas no aberrant calcifications were present in our patients. Our surprising result suggests a different pathway involved in the generation of ARHR and possible additional functions for ENPP1. 相似文献
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Marijn Rutgers Daniël BF Saris Wouter JA Dhert Laura B Creemers 《Arthritis research & therapy》2010,12(3):R114
Introduction
Intraarticular administration of autologous conditioned serum (ACS) recently demonstrated some clinical effectiveness in treatment of osteoarthritis (OA). The current study aims to evaluate the in vitro effects of ACS on cartilage proteoglycan (PG) metabolism, its composition and the effects on synovial fluid (SF) cytokine levels following intraarticular ACS administration. 相似文献89.
Bergo ES Souto RN Galardo AK Nagaki SS Calado DC Sallum MA 《Memórias do Instituto Oswaldo Cruz》2007,102(3):373-376
Identification of Anopheles nuneztovari Gabaldón and An. goeldii Rozeboom and Gabaldón based on the male genitalia traits is discussed. An. goeldii is in the synonymy of An. nuneztovari, however, characters of the aedeagus of male genitalia distinguish both species. We hypothesize that An. goeldii may be a valid species, however, further studies using molecular characters, especially ITS2 rDNA sequences will be necessary to elucidate the taxonomic status of the species. An. konderi Galv?o and Damasceno and An. forattinii Wilkerson and Sallum are registered for the first time in the state of Amapá. 相似文献
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