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131.
Résumé Capillaria dessetae n. sp. est décrit à partir de spécimens parasites du Lagomorphe Ochotona roylei récoltés au Népal. Le mâle est caractérisé par la présence de deux ailes latéro-caudales longues de 65–70 m, une bourse caudale soutenue par deux expansions bifurquées, un spicule long de 190–220 m, un cirre inerme et un canal éjaculateur long de 1200–1300 m. La femelle est caractérisée par des ornementations cuticulaires péri-vulvaires et un oeuf de grande taille (65–69 × 32–38 m) à surface finement réticulée. Les espèces C. legerae et C. murissylvatici (toutes deux parasites de Rongeurs) sont très proches morphologiquement, avec en particulier des dimensions du spicule et une morphologie des bourses caudales très comparables. Ces trois espèces sont néanmoins bien différenciées par les caractéristiques des oeufs. Une représentation linéaire schématique de l'appareil reproducteur mâle interne est proposée, pour ces trois espèces. Ceci met en relief des différences de longueur du canal éjaculateur et du sphincter, qui sont rarement utilisées en systématique, et permet une diagnose facile des espèces. Une telle représentation schématique linéaire serait utile dans toutes les études taxonomiques de Capillariinae.
Capillaria dessetae n. sp. is described from specimens which are parasites of Ochotona roylei collected in Nepal. Males are characterized by the presence of two laterocaudal alae 65–70 m long, a caudal bursa supported by two forked protrusions, a spicule 190–220 m in length, a non-spiny cirrus and an ejaculatory canal 1200–1300 m in length. Females are characterized by cuticular ornamentations associated with the vulva and large eggs (65–69 × 32–38 m) which have a finely striated surface. The species C. legerae and C. murissylvatici (both parasitic in rodents) are morphologically very close, particularly in the spicule dimensions and in the caudal bursa. These three species, however, are clearly differentiated by characteristics of the eggs. Linear schematic representations of the internal male reproductive tracts are given for the three species. This emphasises the differences in the lengths of the ejaculatory canal and sphincter, which are generally not used in systematics, but which allow clear differential diagnoses of the species. Such linear diagrams would be useful in all taxonomic studies of the Capillariinae.
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ABSTRACT

Standards and policies intended to safeguard nonhuman animal welfare, whether in zoos, farms, or laboratories, have tended to emphasize features of the physical environment. However, research has now made it clear that very different welfare outcomes are commonly seen in facilities using similar environments or conforming to the same animal welfare requirements. This wide variation is almost certainly due, at least in part, to the important effects of the actions of animal care staff on animal welfare. Drawing mostly on the farm animal literature, we propose that this “human dimension” of animal welfare involves seven components: (1) positive human–animal interaction, (2) consistency and familiarity of keepers, (3) treating animals as individuals and taking account of their personalities, (4) the attitudes and personalities of keepers, (5) the keepers’ knowledge and experience, (6) the keepers’ own well-being, and (7) the influence of facility design on how keepers and others interact with the animals. We suggest that attention to these human factors provides major scope for improving the welfare of animals in zoos.  相似文献   
133.
Citizen science can play an important role in school science education. Citizen science is particularly relevant to addressing current societal environmental sustainability challenges, as it engages the students directly with environmental science and gives students an understanding of the scientific process. In addition, it allows students to observe local representations of global challenges. Here, we report a citizen science programme designed to engage school‐age children in real‐world scientific research. The programme used standardized methods deployed across multiple schools through scientist–school partnerships to engage students with an important conservation problem: habitat for pollinator insects in urban environments. Citizen science programmes such as the programme presented here can be used to enhance scientific literacy and skills. Provided key challenges to maintain data quality are met, this approach is a powerful way to contribute valuable citizen science data for understudied, but ecologically important study systems, particularly in urban environments across broad geographical areas.  相似文献   
134.
A non-native incursion of the collembolan, Xenylla sp. was found within the hydroponics facility at Davis Station, East Antarctica in May 2014. A rapid response was implemented to eradicate the incursion, including localised insecticide use, incineration of plants and growing media, sterilisation of the facility and three cycles of freezing/thawing of both internal rooms and external sub floor areas. Two consecutive years of summer monitoring programs have not detected any Collembola in station buildings or in the surrounding environment, suggesting the eradication was successful. This case highlights the importance of a multiple barrier approach to non-native species risks, and how activation of the last barrier—regular surveillance—resulted in early detection. The use of an online, real-time incident reporting system facilitated efficient communication between scientific experts, operational managers and expeditioners on site, resulting in a rapid and effective response following detection and potentially the first successful eradication of a non-native microarthropod in Antarctica. Monitoring will continue to confirm eradication.  相似文献   
135.
Source–sink theory is an ecological framework that describes how site and habitat-specific demographic rates and patch connectivity can explain population structure and persistence across heterogeneous landscapes. Although commonly used in conservation planning, source–sink theory has rarely been applied to the management of invasive species. This study tested whether the common carp, one of the world’s most invasive species, exhibits source–sink dynamics in a representative watershed in the Upper Mississippi River Basin comprised of a dozen interconnected ponds and lakes. To test for source–sink population structure, we used standard fish sampling techniques, tagging, and genetic assignment methods to describe habitat-specific recruitment rates and dispersal. Five years of sampling revealed that while adult carp were found across the entire watershed, reproductive success (the presence of young carp) was restricted to shallow ponds. Additionally, nearly a third of the carp tagged in a representative pond dispersed into the connected deeper lakes, suggesting that ponds in this system serve as sources and lakes as sinks. This possibility was confirmed by microsatellite analysis of carp tissue samples (n = 1041) which revealed the presence of two distinct strains of carp cohabitating in the lakes, whose natal origins could be traced back to one of two pond systems, with many adult carp attempting to migrate back into these natal ponds to spawn. We conclude that the distribution and persistence of invasive carp in complex interconnected systems may often be driven by source–sink dynamics and that their populations could be controlled by suppressing reproduction in source habitats or by disrupting dispersal pathways, instead of culling individuals from sink habitats.  相似文献   
136.
Biological invasions are projected to be the main driver of biodiversity and ecosystem function loss in lakes in the 21st century. However, the extent of these future losses is difficult to quantify because most invasions are recent and confounded by other stressors. In this study, we quantified the outcome of a century‐old invasion, the introduction of common carp to North America, to illustrate potential consequences of introducing non‐native ecosystem engineers to lakes worldwide. We used the decline in aquatic plant richness and cover as an index of ecological impact across three ecoregions: Great Plains, Eastern Temperate Forests and Northern Forests. Using whole‐lake manipulations, we demonstrated that both submersed plant cover and richness declined exponentially as carp biomass increased such that plant cover was reduced to <10% and species richness was halved in lakes in which carp biomass exceeded 190 kg ha?1. Using catch rates amassed from 2000+ lakes, we showed that carp exceeded this biomass level in 70.6% of Great Plains lakes and 23.3% of Eastern Temperate Forests lakes, but 0% of Northern Forests lakes. Using model selection analysis, we showed that carp was a key driver of plant species richness along with Secchi depth, lake area and human development of lake watersheds. Model parameters showed that carp reduced species richness to a similar degree across lakes of various Secchi depths and surface areas. In regions dominated by carp (e.g., Great Plains), carp had a stronger impact on plant richness than human watershed development. Overall, our analysis shows that the introduction of common carp played a key role in driving a severe reduction in plant cover and richness in a majority of Great Plains lakes and a large portion of Eastern Temperate Forests lakes in North America.  相似文献   
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138.
The wheat gene Lr34 confers durable and partial field resistance against the obligate biotrophic, pathogenic rust fungi and powdery mildew in adult wheat plants. The resistant Lr34 allele evolved after wheat domestication through two gain‐of‐function mutations in an ATP‐binding cassette transporter gene. An Lr34‐like fungal disease resistance with a similar broad‐spectrum specificity and durability has not been described in other cereals. Here, we transformed the resistant Lr34 allele into the japonica rice cultivar Nipponbare. Transgenic rice plants expressing Lr34 showed increased resistance against multiple isolates of the hemibiotrophic pathogen Magnaporthe oryzae, the causal agent of rice blast disease. Host cell invasion during the biotrophic growth phase of rice blast was delayed in Lr34‐expressing rice plants, resulting in smaller necrotic lesions on leaves. Lines with Lr34 also developed a typical, senescence‐based leaf tip necrosis (LTN) phenotype. Development of LTN during early seedling growth had a negative impact on formation of axillary shoots and spikelets in some transgenic lines. One transgenic line developed LTN only at adult plant stage which was correlated with lower Lr34 expression levels at seedling stage. This line showed normal tiller formation and more importantly, disease resistance in this particular line was not compromised. Interestingly, Lr34 in rice is effective against a hemibiotrophic pathogen with a lifestyle and infection strategy that is different from obligate biotrophic rusts and mildew fungi. Lr34 might therefore be used as a source in rice breeding to improve broad‐spectrum disease resistance against the most devastating fungal disease of rice.  相似文献   
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140.
BackgroundIn Uganda, abortion is permitted only when the life of a woman is in danger. This restriction compels the perpetuation of the practice in secrecy and often under unsafe conditions. In 2003, 294,000 induced abortions were estimated to occur each year in Uganda. Since then, no other research on abortion incidence has been conducted in the country.MethodsData from 418 health facilities were used to estimate the number and rate of induced abortion in 2013. An indirect estimation methodology was used to calculate the annual incidence of induced abortions ─ nationally and by major regions. The use of a comparable methodology in an earlier study permits assessment of trends between 2003 and 2013.ResultsIn 2013, an estimated 128,682 women were treated for abortion complications and an estimated 314,304 induced abortions occurred, both slightly up from 110,000 and 294,000 in 2003, respectively. The national abortion rate was 39 abortions per 1,000 women aged 15–49, down from 51 in 2003. Regional variation in abortion rates is very large, from as high as an estimated 77 per 1,000 women 15–49 in Kampala region, to as low as 18 per 1,000 women in Western region. The overall pregnancy rate also declined from 326 to 288; however the proportion of pregnancies that were unintended increased slightly, from 49% to 52%.ConclusionUnsafe abortion remains a major problem confronting Ugandan women. Although the overall pregnancy rate and the abortion rate declined in the past decade, the majority of pregnancies to Ugandan women are still unintended. These findings reflect the increase in the use of modern contraception but also suggest that a large proportion of women are still having difficulty practicing contraception effectively. Improved access to contraceptive services and abortion-related care are still needed.  相似文献   
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