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991.
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Lavado Nieves de la Concepción Juan García Babiano Reyes Cintas Pedro Light Mark E. 《Origins of life and evolution of the biosphere》2019,49(3):163-185
Origins of Life and Evolution of Biospheres - In line with the postulated intermediacy of aminoxazoles derived from small sugars toward the direct assembly of nucleoside precursors, we show here a... 相似文献
994.
González Pamela Dettleff Phillip Valenzuela Cristián Estrada Juan Manuel Valdés Juan Antonio Meneses Claudio Molina Alfredo 《Molecular biology reports》2019,46(6):5875-5882
Molecular Biology Reports - The red cusk-eel (Genypterus chilensis) is a native Chilean species with a high-value market, with the potential to diversify Chilean aquaculture. The objective of this... 相似文献
995.
Patricia Ysabel Condorhuamán-Alvarado Teresa Pareja-Sierra Angélica Muñoz-Pascual Pilar Sáez-López Cristina Ojeda-Thies Teresa Alarcón-Alarcón María Concepción Cassinello-Ogea Jose Luis Pérez-Castrillón Paloma Gómez-Campelo Laura Navarro-Castellanos Ángel Otero-Puime Juan Ignacio González-Montalvo 《Revista espa?ola de geriatría y gerontología》2019,54(5):257-264
BackgroundThe Spanish National Hip Fracture Registry (or Registro Nacional de Fractura de Cadera, RNFC) is a database of hip fracture patients admitted to Spanish hospitals. Its goals include assessment and continuous improvement of the care process.ObjectivesTo (1) establish a series of indicators, (2) evaluate their initial fulfillment, (3) propose quality standards, (4) suggest recommendations to facilitate standards compliance, and (5) monitor the indicators.MethodThe indicators fulfilled the criteria of (1) evaluating the process or outcome, (2) being clinically relevant for patients, (3) being modifiable through changes in healthcare practice, and (4) being considered important by the RNFC participants. The first quartile obtained by the group of hospitals in each of the respective variables was proposed as the standard. The Indicators Advisory Committee (IAC) elaborated a list of recommendations for each indicator, based on the available evidence.ResultsSeven indicators were chosen. These indicators (its baseline compliance vs. the standard to be reached, respectively) were: the proportion of patients receiving surgery within 48 h (44% vs. 63%), mobilized the first postoperative day (56% vs. 86%), with antiosteoporotic medication at discharge (32% vs. 61%), with calcium supplements at discharge (46% vs. 77%), with vitamin D supplements at discharge (67% vs. 92%), who developed pressure ulcers during hospitalization (7.2% vs. 2.1%) and with independent mobility at 30 days (58% vs. 70%). The IAC has established 25 recommendations for improving care.ConclusionThe indicators and standards chosen are presented, as well as the list of recommendations. This process completes the first step to improve quality of care. The results will be evaluated 6 months after implementing the recommendations. 相似文献
996.
Wang Xiao-Peng Ye Pin Lv Jiao Zhou Lei Qian Zhong-Yi Huang Yong-Jie Mu Zhi-Hao Wang Xie Liu Xin-jie Wan Qi Yang Zhi-Hong Wang Fang Zou Ying-Ying 《Neurochemical research》2019,44(4):978-993
Neurochemical Research - Cognitive impairment in diabetes (CID) is a severe chronic complication of diabetes mellitus (DM). It has been hypothesized that diabetes can lead to cognitive dysfunction... 相似文献
997.
Fifteen paired fossil populations of Microtus arvalis and Microtus agrestis from southwestern Europe have been analysed from a morphological and morphometric point of view. The sites under consideration are located in the northern Iberian Peninsula and southern France, from the Middle Pleistocene to the end of the Late Pleistocene. The aim of this study is to stress once again the importance of keeping these two species separated in the fossil record in order to recognize specific trends of evolution and divergence and to obtain more precise information on palaeoclimatic and palaeoenvironmental conditions. It was possible to observe remarkable intraspecific differences between Middle and Late Pleistocene populations of both species. Furthermore, in synchronic co-specific populations from the Late Pleistocene, climatic and geographic conditions seem to exert a major influence in shaping intraspecific changes in dental pattern. 相似文献
998.
ngel A. del Río‐Chvez Hugo A. García‐Gutirrez Luisa U. Romn‐Marín Lidia Beiza‐Granados Carlos M. Cerda‐García‐Rojas Pedro Joseph‐Nathan Juan D. Hernndez‐Hernndez 《Chirality》2019,31(11):934-946
The epimeric diterpenes (+)‐(1S,3E,7E,11S,12S)‐verticilla‐3,7‐dien‐12‐ol ( 1 ), isolated from Bursera suntui, and (+)‐(1S,3E,7E,11S,12R)‐verticilla‐3,7‐dien‐12‐ol ( 2 ), isolated from Bursera kerberi, gave the same Wagner‐Meerwein rearrangement product (?)‐(1E,4Z,8Z,11S,12R)‐phomacta‐1,(15)4,8‐triene ( 3 ). The Et2O:BF3‐induced transformations evidence that verticillenes and phomactanes, both containing the bicyclo[9.3.1]pentadecane skeleton, are biogenetically related through the verticillen‐12‐yl cation ( A + ), which also is a key intermediate in the biosynthetic pathways to generate antitumor taxanes. Molecular modeling using the Monte Carlo protocol, followed by density functional theory (DFT) geometry optimization employing the hybrid functionals B3LYP and B3PW91, both with the DGDZVP basis set, secured the configuration of 3 as followed from the good agreement between the calculated and experimental vibrational circular dichroism spectra. Similar DFT calculations allowed determining the absolute configuration of (+)‐(1R,4R,5R,8S,9S,11S,12R,15R)‐1,15:4,5:8,9‐triepoxyphomactane ( 9 ), which surprisingly derives from epoxidation of the second minimum energy conformer of 3 . 相似文献
999.
David Gmez‐Blanco Simone Santoro Antoni Borrs Josep Cabrera Juan Carlos Senar Pim Edelaar 《Journal of avian biology》2019,50(12)
Dozens of morphologically differentiated populations, subspecies and species of crossbills (genus Loxia) exist. It has been suggested that this divergence is due to variation in the conifer cones that each population specialises upon, requiring a specific beak size to efficiently separate the cone scales. If so, apparent survival should depend on beak size. To test this hypothesis, we undertook multievent capture–recapture modelling for 6844 individuals monitored during 27 years in a Pyrenean common crossbill L. curvirostra population in a forest of mountain pine Pinus uncinata. Apparent survival was indeed related to beak width, resulting in stabilizing selection around an optimum that was close to the observed mean beak width, indicating that local crossbill beak morphology is adapted to the conifer they feed upon. Both natural selection (selective mortality) and selective emigration of maladapted individuals may explain our findings. As is often the case in capture–recapture analyses but rarely recognised, we could not formally decompose apparent survival into selective mortality versus selective permanent emigration. Nonetheless, there are several indications that selective permanent emigration should not be fully excluded. First, natural selection by itself would have to be unusually strong compared to other empirical estimates to create the observed pattern of apparent survival. Second, the observed mean beak width was a bit lower than the estimated optimum beak width. This can be explained by immigration of crossbills with smaller beaks originating from southern populations, which may subsequently have left the study area permanently in response to low food intake. This is in line with a detected transient effect in the data, yet apparently little influx from crossbills from northern Europe. When permanent emigration is phenotypically selective this will have ecological and evolutionary consequences, so this possibility deserves more attention in general. 相似文献
1000.
Manuel Soler Alejandro B. Rodríguez‐Navarro Toms Prez‐Contreras Juan Manuel García‐Ruiz Juan Jos Soler 《Journal of avian biology》2019,50(11)
Obligate avian brood parasites lay stronger eggs than their hosts or non‐parasitic relatives because they are rounder and have a thicker eggshell. Additionally, some other characteristics of the brood parasitic eggshells related to their microstructure such as size and orientation of calcite crystal units could also contribute to generating even stronger shells. An eggshell microstructure formed by small randomly oriented calcite crystal units can increase the robustness of the eggshells of birds. Here, the eggshell microstructure of avian brood parasites as well as their hosts have been characterized in detail, using X‐ray diffraction analyses to estimate the size and degree of orientation of calcite crystal units making the eggshell. Specifically, the brood parasitic great spotted cuckoo Clamator glandarius and two hosts (jackdaws Corvus monedula and magpie Pica pica) and one non‐host species (the pigeon, Columba livia domestica) were considered. Calcite crystal of the eggshell of the brood parasitic species was smaller and more randomly oriented than those of the eggshells of non‐parasitic species, which suggest that eggshell microstructure would contribute to explain why parasitic eggs are more resistant to breakage than those of their hosts. 相似文献