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51.
Se describe e ilustra como especie nueva a Polianthes zapopanensis
, conocida de la parte centro-sur del estado de Jalisco, México. Por su inflorescencia en forma de racimo, esta especie se
ubica en Polianthes subgénero Bravoa. Las hojas de las plantas en floración no se agrupan para formar una roseta. A diferencia de las especies hasta ahora descritas
tiene el eje de la inflorescencia generalmente ramificado, con una o dos ramas de 6–24 cm de largo, entre el quinto y el octavo
nudos, sus flores son infundibuliformes y crasas. Muestra similitudes morfológicas con Polianthes geminiflora var. geminiflora, P. geminiflora var. clivicola, P. geminiflora var. pueblensis, P. graminifolia y P. oaxacana. Se presenta una clave para la determinación de las especies del estado de Jalisco, México. 相似文献
52.
Ricardo J Eloy Alves Wolfgang Wanek Anna Zappe Andreas Richter Mette M Svenning Christa Schleper Tim Urich 《The ISME journal》2013,7(8):1620-1631
The functioning of Arctic soil ecosystems is crucially important for global climate, and basic knowledge regarding their biogeochemical processes is lacking. Nitrogen (N) is the major limiting nutrient in these environments, and its availability is strongly dependent on nitrification. However, microbial communities driving this process remain largely uncharacterized in Arctic soils, namely those catalyzing the rate-limiting step of ammonia (NH3) oxidation. Eleven Arctic soils were analyzed through a polyphasic approach, integrating determination of gross nitrification rates, qualitative and quantitative marker gene analyses of ammonia-oxidizing archaea (AOA) and bacteria (AOB) and enrichment of AOA in laboratory cultures. AOA were the only NH3 oxidizers detected in five out of 11 soils and outnumbered AOB in four of the remaining six soils. The AOA identified showed great phylogenetic diversity and a multifactorial association with the soil properties, reflecting an overall distribution associated with tundra type and with several physico-chemical parameters combined. Remarkably, the different gross nitrification rates between soils were associated with five distinct AOA clades, representing the great majority of known AOA diversity in soils, which suggests differences in their nitrifying potential. This was supported by selective enrichment of two of these clades in cultures with different NH3 oxidation rates. In addition, the enrichments provided the first direct evidence for NH3 oxidation by an AOA from an uncharacterized Thaumarchaeota–AOA lineage. Our results indicate that AOA are functionally heterogeneous and that the selection of distinct AOA populations by the environment can be a determinant for nitrification activity and N availability in soils. 相似文献
53.
Miguel?Rivera-LugoEmail author Abisaí?García-Mendoza June?Simpson Eloy?Solano Katia?Gil-Vega 《Plant Systematics and Evolution》2018,304(8):969-979
The Agave angustifolia complex, distributed from Mexico to Costa Rica, comprises four species and five varieties, including three species used for mescal production. The complex is represented in the Mexican state of Oaxaca by two wild taxa, A. angustifolia var. angustifolia and A. angustifolia var. rubescens, the cultivated form A. angustifolia “Espadín” and the partially cultivated species A. rodacantha. The aims of this study were to investigate the morphological and genetic variation of the A. angustifolia complex in the state of Oaxaca and to identify traits useful for taxonomic delimitation. Four wild and three cultivated populations of A. angustifolia from Oaxaca, one population of A. tequilana from Guanajuato and one population of A. angustifolia from Sonora were sampled for morphological, genetic and cytometric analyses. We showed that cultivated populations of A. angustifolia “Espadin,” A. rhodacantha and A. tequilana could be clearly differentiated from wild populations. Furthermore, the domesticated populations of A. angustifolia, known locally as “Espadin,” had a higher ploidy level and lower genetic variation than their related wild populations. The population of A. angustifolia from Sonora could be recognized as a different entity. Populations of A. rhodacantha need to be studied throughout their entire distribution area to further evaluate their taxonomic delimitation. 相似文献
54.
C Grilo J Sousa F Ascensão H Matos I Leitão P Pinheiro M Costa J Bernardo D Reto R Lourenço M Santos-Reis E Revilla 《PloS one》2012,7(9):e43811
Background
Understanding the ecological consequences of roads and developing ways to mitigate their negative effects has become an important goal for many conservation biologists. Most mitigation measures are based on road mortality and barrier effects data. However, studying fine-scale individual spatial responses in roaded landscapes may help develop more cohesive road planning strategies for wildlife conservation.Methodology/Principal Findings
We investigated how individuals respond in their spatial behavior toward a highway and its traffic intensity by radio-tracking two common species particularly vulnerable to road mortality (barn owl Tyto alba and stone marten Martes foina). We addressed the following questions: 1) how highways affected home-range location and size in the immediate vicinity of these structures, 2) which road-related features influenced habitat selection, 3) what was the role of different road-related features on movement properties, and 4) which characteristics were associated with crossing events and road-kills. The main findings were: 1) if there was available habitat, barn owls and stone martens may not avoid highways and may even include highways within their home-ranges; 2) both species avoided using areas near the highway when traffic was high, but tended to move toward the highway when streams were in close proximity and where verges offered suitable habitat; and 3) barn owls tended to cross above-grade highway sections while stone martens tended to avoid crossing at leveled highway sections.Conclusions
Mortality may be the main road-mediated mechanism that affects barn owl and stone marten populations. Fine-scale movements strongly indicated that a decrease in road mortality risk can be realized by reducing sources of attraction, and by increasing road permeability through measures that promote safe crossings. 相似文献55.
Jonàs Juan-Mateu Maria José Rodríguez Andrés Nascimento Cecilia Jiménez-Mallebrera Lidia González-Quereda Eloy Rivas Carmen Paradas Marcos Madruga Pedro Sánchez-Ayaso Cristina Jou Laura González-Mera Francina Munell Manuel Roig-Quilis Maria Rabasa Aurelio Hernández-Lain Jorge Díaz-Manera Eduard Gallardo Jordi Pascual Edgard Verdura Jaume Colomer Montserrat Baiget Montse Olivé Pia Gallano 《Orphanet journal of rare diseases》2012,7(1):1-13
Background
Neonatal screening for Pompe disease has been introduced in Taiwan and a few U.S. states, while other jurisdictions including some European countries are piloting or considering this screening. First-tier screening flags both classic infantile and late-onset Pompe disease, which challenges current screening criteria. Previously, advocacy groups have sometimes supported expanded neonatal screening more than professional experts, while neutral citizens' views were unknown. This study aimed to measure support for neonatal screening for Pompe disease in the general public and to compare it to support among (parents of) patients with this condition. The study was done in the Netherlands, where newborns are not currently screened for Pompe disease. Newborn screening is not mandatory in the Netherlands but current uptake is almost universal.Methods
A consumer panel (neutral group) and (parents of) patients with Pompe disease (Pompe group) were sent information and a questionnaire. Responses were analyzed of 555 neutral and 58 Pompe-experienced informants who had demonstrated sufficient understanding.Results
87% of the neutral group and 88% of the Pompe group supported the introduction of screening (95% CI of difference -10 to 7%). The groups were similar in their moral reasoning about screening and acceptance of false positives, but the Pompe-experienced group expected greater benefit from neonatal detection of late-onset disease. Multivariate regression analysis controlling for demographics confirmed that approval of the introduction of screening was independent of having (a child with) Pompe disease. Furthermore, respondents with university education, regardless of whether they have (a child with) Pompe disease, were more likely to be reluctant about the introduction of screening than those with less education, OR for approval 0.29 (95% CI 0.18 to 0.49, p < 0.001).Conclusions
This survey suggests a rather high level of support for newborn screening for Pompe disease, not only among those who have personal experience of the disease but also among the general public in the Netherlands. Optional screening on the basis of informed parental consent is probably unrealistic, underlining the need for new guidelines to help policymakers in their consideration of newborn screening for broad phenotype conditions. 相似文献56.
Christiane Santos Matos José Eloy dos Santos Júnior Fernanda Alvarenga Cardoso Medeiros Eliana Furtado Jo?o Carlos Pinto Dias 《Memórias do Instituto Oswaldo Cruz》2014,109(3):374-378
Recognising the importance of Chagas disease in Brazil, Bambuí set up epidemiological
surveillance for Chagas disease in 1974 and was the first municipality to do so. To
ascertain the current epidemiology of Chagas disease in this municipality, 1.782
blood samples from the general population were analysed; 7.7% of samples were found
to be seropositive for Chagas disease. A strong positive correlation between
increasing age and Chagas disease was evident in both genders, with the highest
prevalence in individuals aged over 60 years. Clinically, the cardiodigestive form of
Chagas disease was the most common in these samples. These data confirm the
interruption of Trypanosoma cruzi transmission, in parallel with a
still important residual morbidity of Chagas disease in the county, thus supporting
political decisions that will prioritise epidemiological surveillance and medical
treatment of Chagas disease in the coming years. 相似文献
57.
58.
The occurrence of intestinal parasites in swine slurry and their removal in activated sludge plants 总被引:1,自引:0,他引:1
Thirteen intensive pig farms and two activated sludge treatment plants for pig slurry in north-western Spain were studied from April 2005 to June 2006 in order to evaluate the presence of enteric pathogens (Cryptosporidium, Giardia and helminths) and the efficiency with which they were removed. These parasites were present on 53%, 7% and 38% of the farms studied, respectively, with concentrations of 10(4)-10(5) oocysts per litre (/L) for Cryptosporidium, 10(3)cysts/L for Giardia and 10(2)-10(3) eggs/L for helminths. The overall removal of parasites in the pig slurry treatment plants ranged from 86.7% to over 99.99%. The results revealed a constant reduction at each stage of the treatment system, with activated sludge processes being the most effective treatment in reducing pathogens in pig slurry, 78-81% for Cryptosporidium oocysts and over 99.9% for helminth eggs. A heat drying procedure for sludge removed 4.3 log units of Cryptosporidium oocysts, demonstrating the excellent effectiveness of this treatment for reducing pathogens in sludge intended to be applied to land. 相似文献
59.
Proteins dominate in the surface layers formed on materials exposed to extracellular polymeric substances from bacterial cultures 总被引:1,自引:0,他引:1
Yi Yang Agata J. Wikieł Leonardo T. Dall’Agnol Pierre Eloy Michel J. Genet José J. G. Moura 《Biofouling》2016,32(1):95-108
The chemical compositions of the surface conditioning layers formed by different types of solutions (from isolated EPS to whole culture media), involving different bacterial strains relevant for biocorrosion were compared, as they may influence the initial step in biofilm formation. Different substrata (polystyrene, glass, steel) were conditioned and analyzed by X-ray photoelectron spectroscopy. Peak decomposition and assignment were validated by correlations between independent spectral data and the ubiquitous presence of organic contaminants on inorganic substrata was taken into account. Proteins or peptides were found to be a major constituent of all conditioning layers and polysaccharides were not present in appreciable concentrations; the proportion of nitrogen which may be due to DNA was lower than 15%. There was no significant difference between the compositions of the adlayers formed from different conditioning solutions, except for the adlayers produced with tightly bound EPS extracted from D. alaskensis. 相似文献
60.
State of the art in the functioning of shallow Mediterranean lakes: workshop conclusions 总被引:1,自引:0,他引:1
Meryem Beklioglu Susana Romo Ifigenia Kagalou Xavier Quintana Eloy Bécares 《Hydrobiologia》2007,584(1):317-326
Studies on shallow lakes from the north temperate zone show that they alternate between clear and turbid water states in response
to control factors. However, the ecology of semi-arid to arid shallow Mediterranean lakes is less explored. Hydrological effects
(e.g. water level fluctuations, water residence time) on major ions and nutrient dynamics and processes, and ecology of submerged
macrophytes appear to have a crucial role for food webs in shallow Mediterranean lakes. Nutrient control may be of greater
priority in eutrophicated warm shallow lakes than in similar lakes at higher latitudes. This will be relevant for the implementation
of the European Water Framework Directive, and conservation and management of these ecosystems. Strong trophic cascading effects
of fish resulting from dominance of omnivorous and benthivorous fish species, whose diversity is usually high, together with
frequent spawning and absence of efficient piscivores, seem to be the reason for the lack of large-bodied grazers that could
control phytoplankton. However, such effects may vary within the region depending on fish distribution and community. These
factors need elaboration in order to allow shallow lake ecologists and managers to develop better restoration strategies for
eutrophicated shallow Mediterranean lakes. Consequently, modifications for the implementation of the European Water Framework
Directive for determining ecological status in shallow Mediterranean lakes appear to be necessary. Furthermore, the implications
of climate warming may be even more challenging than in high latitude lakes since shallow lakes in the Mediterranean region
are among the most sensitive to extreme climate changes. There is an urgent need for data on the ecology of shallow lakes
in the region. An appeal is made for international cooperation, development of large-scale research and information exchange
to facilitate this and a web-based discussion list has been implemented. 相似文献