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Natural disasters in populated areas may result in massive casualties and extensive destruction of infrastructure. Humanitarian aid delegations may have to cope with the complicated issue of patient prioritization under conditions of severe resource scarcity. A triage model, consisting of five principles, is proposed for the prioritization of patients, and it is argued that rational and reasonable agents would agree upon them. The Israel Defense Force's humanitarian mission to Haiti following the 2010 earthquake serves as a case study for the various considerations taken into account when designing the ethical‐clinical policy of field hospitals. The discussion focuses on three applications: the decision to include an intensive care unit, the decision to include obstetrics and neonatal units, and the treatment policy for compound fractures.  相似文献   
996.
The conservation of migratory songbirds is often impeded by a lack of understanding of how populations in breeding and wintering areas are geographically linked (migratory connectivity). In recent years, light‐level geolocators have improved our understanding of migratory connectivity. Such information is valuable for evaluating how conservation efforts align between the breeding and non‐breeding areas of at‐risk species, and help to more effectively prioritize the allocation of conservation funding. Golden‐winged Warblers (Vermivora chrysoptera) are imperiled migratory songbirds, but the extent to which conservation efforts in their breeding and non‐breeding areas coincide with patterns of migratory connectivity are not well known. We used light‐level geolocators to evaluate the extent to which conservation actions targeting Golden‐winged Warblers in Nicaragua and in their breeding range in North America align with patterns of migratory connectivity. We recovered six of 22 geolocators that had been deployed on male Golden‐winged Warblers at the El Jaguar Reserve during the winter of 2015–2016. All six males migrated to breeding areas in the western Great Lakes region that includes eastern Minnesota, northern Wisconsin, southwestern Ontario, and Michigan's Upper Peninsula. All six males also had similar migration routes, with spring stopovers in southern Mexico, Guatemala, and Belize, a trans‐Gulf flight, and a stopover in the region of Louisiana, Arkansas, eastern Oklahoma, and Texas. Our results, in combination with those of previous studies, demonstrate strong migratory connectivity between portions of the breeding and winter distributions of Golden‐winged Warblers currently targeted for conservation. However, additional studies are needed to improve our understanding of the stopover ecology of Golden‐winged Warblers, especially in areas where they remain for extended periods of time. Finally, patterns of migratory connectivity revealed in our study should be used in combination with existing demographic parameters for Golden‐winged Warblers in the western Great Lakes and Nicaragua to help inform full life cycle population models for this imperiled songbird.  相似文献   
997.
According to mitochondrial data, the common mole, Talpa europaea, is paraphyletic. This could be explained by either an ancient introgression of mtDNA from the Iberian blind mole T. occidentalis to T. europaea, or the existence of a differentiated taxonomic entity in northern Spain that needs to be described. In this study, we combined mitochondrial (Cytb) and nuclear (HDAC2) data to investigate these two alternative hypotheses. Based on both mitochondrial and nuclear data and an extensive geographical sampling (399 sequenced individuals), we show that the populations of T. europaea from Spain and south‐western France (south of the Loire River) are phylogenetically closer to T. occidentalis than to T. europaea. The Spanish–French lineage has some morphological characters resembling more to T. occidentalis (e.g. eyes) and others resembling more to T. europaea (external measurements, mesostyle of the first upper molar). It also seems to have several distinctive dental characters, suggesting that it should be recognized as a new species. Within the three lineages, we found a marked phylogeographical pattern, with several allopatric or parapatric lineages, dating from the Pleistocene. Our genetic data combined with species distribution models support the presence of several putative glacial refugia during glacial maxima for each species.  相似文献   
998.
Deep‐sea lobsters previously assigned to the family Thaumastochelidae Bate, 1888, the thaumastocheliforms, have very distinctive, greatly unequal first chelipeds, with the right side extremely elongate and pectinate, and in having short, quadrate pleonal pleura. Despite interesting morphology and a long taxonomic history, the phylogeny of the group has received little detailed analysis. Here, we conduct a species‐level phylogenetic analysis of the thaumastocheliforms based on morphological and molecular data (three mitochondrial genes: COI, 16S rDNA and 12S rDNA; two nuclear protein‐coding genes: H3 and NaK) to robustly reconstruct their evolutionary history and estimate divergence times. Separate and combined analyses of all data sources support thaumastocheliform monophyly, but as a clade deeply nested within the Nephropidae supporting recent synonymy of Thaumastochelidae with Nephropidae. Combined and molecular‐only analyses support generic monophyly of all three thaumastocheliform genera and Dinochelus as sister to Thaumastochelopsis, fully corroborating the current, morphology‐based taxonomy. In contrast, Thaumastocheles is recovered as paraphyletic in morphology‐only analyses owing to minimal character support. The Cretaceous–Paleogene Oncopareia was recovered as a stem‐lineage thaumastocheliform. The fossil record indicates that the thaumastocheliforms once lived in shallow, continental shelf depths, but moved into deeper water in the Cenozoic where they occur today. The thaumastocheliforms originated in northern Europe during the Mid‐Late Cretaceous and later dispersed westwards to the south‐eastern Pacific through the western Atlantic and eastwards to the western Pacific through the Indian Ocean. Thaumastochelopsis can be considered the most derived thaumastocheliform genus based on the degree of structural reduction relative to other thaumastocheliforms, its remote geographical occurrence (Australia) from the hypothesised place of origin (northern Europe) and its more recent estimated divergence than other genera (28 Mya for the MRCA of extant species of the genus).  相似文献   
999.
Cryptic species are common in the ocean, particularly among marine invertebrates such as octopuses. Delineating cryptic species is particularly problematic in octopus taxonomy where the plasticity recorded among taxonomic characters often results in low resolution at the species level. This study investigated the morphological relationships among seven phylogenetic clades (identified using cytochrome c oxidase subunit I) of the broadly distributed Octopus vulgaris species complex and close relatives. Morphological analyses in this study were successful in delimiting O. sinensis, Brazilian Ovulgaris and O. vulgaris sensu stricto, which was congruent with the molecular findings of this study. Analyses based on male morphology were successful in distinguishing 14 of 15 total pairwise comparisons and proved to be a more reliable indicator of species‐level relationships in comparison with female morphology. The majority of characters with the greatest discriminatory power were male sexual traits. Significant morphological differences were also recorded among sampling localities of conspecifics, with phenotype showing correlation with local environmental data. The findings of this study support the hypothesis that multiple O. vulgaris‐like species are currently being incorrectly treated under a single species name, O. vulgaris. Octopuses being exported globally under the name O. vulgaris are of extremely high fisheries market value and profile. Our findings have potentially significant implications for the naming and conservation of commercially harvested members of this species complex throughout their ranges.  相似文献   
1000.
Species of the genus Meladema (Dytiscidae, Colymbetinae) are some of the largest macroinvertebrates in the western Palearctic region, being top predators in fishless streams. Two of the three described species, Meladema imbricata (Wollaston, 1871) and Meladema lanio (Fabricius, 1775) are Macaronesian endemics from the Canary Islands and Madeira, respectively, while the third, Meladema coriacea Laporte, 1835, is widely distributed from Morocco and the Iberian Peninsula to Turkey, including the Canary Islands. Previous phylogenetic analysis using only mitochondrial markers revealed the existence of two cryptic lineages within M. coriacea, one restricted to Corsica and the other including the rest of sampled populations. We reconstruct here the evolutionary history of the species of Meladema using a more comprehensive sampling covering its whole geographical range, adding nuclear markers and Bayesian molecular dating. Using environmental niche modelling, we test for possible differences in climatic preferences among lineages and reconstruct their ancestral climatic niche. Our results strongly supported the existence of four monophyletic lineages represented by the three recognized species plus a fourth cryptic lineage with populations of M. coriacea from the Tyrrhenian islands (Corsica, Sardinia and Montecristo). This pattern is not likely to be the result of mitochondrial artefacts due to Wolbachia infection, as all 11 tested individuals were negative for this parasite. Dating analysis placed the origin of Meladema in the Middle Miocene although diversification among extant Meladema lineages started in the early Pleistocene and took place in a relatively short time period. Phylogeographic analysis inferred a continental origin of Meladema, with an independent colonization of the Macaronesian and Mediterranean islands. From the south‐western Mediterranean region, the continental M. coriacea expanded its range up to Bulgaria and Turkey in the northern basin and to Tunisia in the southern. Results of niche modelling showed that seasonality is the critical factor in shaping the current distribution of Meladema. Island lineages (M. imbricata, M. lanio and the Tyrrhenian lineage of M. coriacea) occur in sites with low seasonality, within the range of the reconstructed ancestral climatic niche of the genus. On the contrary, continental M. coriacea expanded its range to localities outside the ancestral climatic range of the genus, with a higher seasonality and aridity.  相似文献   
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