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101.
Three exterilium larvae (18.2 mm notochord length to 113.3 mm standard length) of an ophidiid, Lamprogrammus shcherbachevi, from the western North Pacific are described. The specimens had a highly specialized morph with a remarkably elongate trailing
gut and ventral coracoid process, and many elongate anterior dorsal fin rays, as occur in other exterilium larvae, but were
characterized by unique melanophore patterns (a cluster of melanophores on the back of the stalked pectoral fin base, a row
of clusters midlaterally on the trunk and caudal region, and further clusters on the trailing gut). Although the largest specimen
(113.3 mm standard length, much larger than the previously recorded maximum size of exterilium larvae) retained typical features
of the exterilium stage, the ventral coracoid process was significantly reduced in size compared with that of a smaller specimen
(37.8 mm standard length). Comparison of the largest specimen with an adult suggests that the anterior dorsal fin rays would
disappear during the transformation stage. 相似文献
102.
A mild bleaching event was observed among Pocillopora spp. in the southern Gulf of California in the spring of 2006. Uniform bleaching occurred in numerous colonies on the upper
portions of their branches. Most (∼90%) colonies that exhibited bleaching contained a species of endosymbiotic dinoflagellate,
Symbiodinium C1b-c, which differed from the Symbiodinium D1 found inhabiting most unbleached colonies. Analysis of chlorophyll fluorescence, indicated a decline in photosystem II
photochemical activity, especially among colonies populated with C1b-c. By early August, most affected colonies had recovered
their normal pigmentation and fluorescence values were once again high for all colonies. No mortality was observed among tagged
bleached colonies nor did symbiont species composition change during recovery. This unusual episode of bleaching did not appear
to be a response to thermal stress, but may have been triggered by high levels of solar radiation during a period of unseasonally
high water clarity in the early spring. 相似文献
103.
Phylogeographic structure and deep lineage diversification of the red alga Chondrus ocellatus Holmes in the Northwest Pacific
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Zi‐Min Hu Jing‐Jing Li Zhong‐Min Sun Jung‐Hyun Oak Jie Zhang Pablo Fresia W. Stewart Grant De‐Lin Duan 《Molecular ecology》2015,24(19):5020-5033
A major goal of phylogeographic analysis using molecular markers is to understand the ecological and historical variables that influence genetic diversity within a species. Here, we used sequences of the mitochondrial Cox1 gene and nuclear internal transcribed spacer to reconstruct its phylogeography and demographic history of the intertidal red seaweed Chondrus ocellatus over most of its geographical range in the Northwest Pacific. We found three deeply separated lineages A, B and C, which diverged from one another in the early Pliocene–late Miocene (c. 4.5–7.7 Ma). The remarkably deep divergences, both within and between lineages, appear to have resulted from ancient isolations, accelerated by random drift and limited genetic exchange between regions. The disjunct distributions of lineages A and C along the coasts of Japan may reflect divergence during isolation in scattered refugia. The distribution of lineage B, from the South China Sea to the Korean Peninsula, appears to reflect postglacial recolonizations of coastal habitats. These three lineages do not coincide with the three documented morphological formae in C. ocellatus, suggesting that additional cryptic species may exist in this taxon. Our study illustrates the interaction of environmental variability and demographic processes in producing lineage diversification in an intertidal seaweed and highlights the importance of phylogeographic approaches for discovering cryptic marine biodiversity. 相似文献
104.
Risks and advantages of using surface laser photogrammetry on free‐ranging marine organisms: a case study on white sharks Carcharodon carcharias
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G. Leurs C. P. O'Connell S. Andreotti M. Rutzen H. Vonk Noordegraaf 《Journal of fish biology》2015,86(6):1713-1728
This study employed a non‐lethal measurement tool, which combined an existing photo‐identification technique with a surface, parallel laser photogrammetry technique, to accurately estimate the size of free‐ranging white sharks Carcharodon carcharias. Findings confirmed the hypothesis that surface laser photogrammetry is more accurate than crew‐based estimations that utilized a shark cage of known size as a reference tool. Furthermore, field implementation also revealed that the photographer's angle of reference and the shark's body curvature could greatly influence technique accuracy, exposing two limitations. The findings showed minor inconsistencies with previous studies that examined pre‐caudal to total length ratios of dead specimens. This study suggests that surface laser photogrammetry can successfully increase length estimation accuracy and illustrates the potential utility of this technique for growth and stock assessments on free‐ranging marine organisms, which will lead to an improvement of the adaptive management of the species. 相似文献
105.
Thomas R. Fleming Aaron G. Maule Trevor Martin Margaret Hainon-McDowell Kate Entwistle Michael A. McClure Colin C. Fleming 《Journal of nematology》2015,47(2):97-104
Anguina pacificae is a significant pest of Poa annua golf course greens in northern California. This study presents the first confirmed case of an A. pacificae infestation outside of North America, where the nematode’s distribution is further restricted to a relatively limited coastal region. Species confirmation was made by morphometric and molecular methods and comparisons to closely related species including the European species, Anguina agropyri. The A. pacificae population detected on an Irish golf course was monitored over a 2-yr period and the life cycle compared with Californian population dynamics. A. pacificae was assessed for the potential risk of spreading to the local agricultural sector, in addition, the biosecurity risks from A. pacificae and plant parasitic nematodes in general were reviewed for northwest Europe. 相似文献
106.
107.
108.
B. Christian Schmidt 《ZooKeys》2015,(527):103-126
The Lacinipolia
vicina (Grote) species complex, previously consisting of Lacinipolia
vicina, Lacinipolia
teligera (Morrison), Lacinipolia
pensilis (Grote), and Lacinipolia
subalba Mustelin is revised to six species: Lacinipolia
vicina (eastern USA), Lacinipolia
teligera (southern Great Plains), Lacinipolia
pensilis (Pacific Northwest and northern Rocky Mountains), Lacinipolia
acutipennis (Grote), stat. rev. (= Lacinipolia
subalba
syn. n.) (western North America), Lacinipolia
sareta (Smith), stat. rev. (Canada and western USA) and Lacinipolia
dimocki, sp. n. (California and Pacific Northwest). Lectotypes are designated for Lacinipolia
vicina, Lacinipolia
teligera and Lacinipolia
pensilis. 相似文献
109.
Alain Migeon 《ZooKeys》2015,(489):15-24
The family Tetranychidae (spider mites) currently comprises 1,275 species and represents one of the most important agricultural pest families among the Acari with approximately one hundred pest species, ten of which considered major pests. The dataset presented in this document includes all the identified spider mites composing the Jean Gutierrez Collection hosted at the CBGP (Montferrier-sur-Lez, France), gathered from 1963 to 1999 during his career at the Institut de Recherche pour le Développement (IRD). It consists of 5,262 specimens corresponding to 1,564 occurrences (combination species/host plant/date/location) of 175 species. Most specimens were collected in Madagascar and other islands of the Western Indian Ocean, New Caledonia and other islands of the South Pacific and Papuasia. The dataset constitutes today the most important one available on Tetranychidae worldwide. 相似文献
110.
Muricea is an amphi-American genus. Verrill proposed dividing the species from the Pacific Ocean into three genera and established the genus Eumuricea for five eastern Pacific species with tubular calyces. Eumuricea is basically characterized by colonies with elongate, cylindrical calyces with truncate margins and star-like opercula, and the occurrence of unilateral spinous spindles. According to these characteristics, Eumuricea does not show enough difference from Muricea to be treated as a separate genus. Original type material of Eumuricea was morphologically analysed and illustrated using optical and scanning electron microscopy. We conclude that the eastern Pacific species should be placed in the genus Muricea and form a group characterised by tubular calyces that comprises four species at present, Muricea
acervata, Muricea
hispida, Muricea
squarrosa, and Muricea
tubigera and a dubious species Muricea
horrida. Lectotypes were designated for Muricea
squarrosa and Muricea
hispida to establish their taxonomic status. The genus Eumuricea has also been misunderstood by former authors who erroneously assigned species to it. For these species we propose new combinations: Swiftia
pusilla, Astrogorgia
splendens and Astrogorgia
ramosa. 相似文献