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Godfrey H. Kagezi Manfred Kaib Philip Nyeko Christopher Bakuneeta Martin Schädler Roland Brandl 《African Journal of Ecology》2011,49(3):267-276
Termites are important decomposers and ‘ecosystem engineers’ in tropical ecosystems. Furthermore, termite assemblages are sensitive to human land‐use intensification and often termite density and the importance of soil‐feeding termites decrease with land‐use intensification. These changes in termite assemblages may also lead to a decrease in termite‐mediated ecosystem processes (e.g. soil formation, cellulose decomposition). We compared density and functional composition of termites with cellulose removal from undisturbed primary forests to farmlands (Kakamega Forest, Western Kenya). In contrast to the expectation, we found no response of termite abundance along the gradient of land‐use intensification. However, as expected, the relative abundance of soil‐feeders decreased from primary forests to farmlands. In contrast, frequency of attack on tissue paper baits and removal of tissue showed a clear hump‐shaped relationship to land‐use intensification with high values in secondary forests. These nonconcordant patterns of density and functional composition of termite assemblages with cellulose removal by termites suggest that it may be misleading to infer changes in a process by the characteristics of the assemblage of organisms that mediate that process. 相似文献
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摘要: 【目的】为了探讨圆唇散白蚁Reticulitermes labralis补充生殖蚁对巢群稳定和发展的作用。【方法】对野外巢群进行调查研究, 及对婚飞成虫通过雌雄配对与补充生殖蚁隔离巢群进行人工饲养的对比研究。【结果】在野外巢群只发现1对原始蚁王蚁后, 而补充生殖蚁的数量最多可达到689头/巢。圆唇散白蚁有3种类型的补充生殖蚁, 即由工蚁转化来的无翅型补充生殖蚁、若蚁转化来的翅芽型补充生殖蚁和末龄若蚁羽化来的拟成虫型补充生殖蚁。实验室条件下婚飞配对群体和隔离群体建群1个月后的存活率分别为64%和96%。建巢初期婚飞配对群体的子代数目增长缓慢, 2个月时的群体数量为6.3±1.54, 10个月时的群体数量也仅为8.4±1.47; 而隔离建群补充生殖蚁2个月时的群体数量为52.4±6.44, 10个月时的群体数量为164.3±20.85, 都高于婚飞配对群体。 此外, 野外巢群的补充蚁后跟原始蚁后一样都具有发达的卵巢。【结论】在圆唇散白蚁中补充生殖蚁是白蚁巢群主要的繁殖力量, 也是建立新巢群的重要繁殖品级。 相似文献
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IDENTIFICATION OF THE FGL‐AMIDE ALLATOSTATIN GENE OF THE PRIMITIVE TERMITE Mastotermes darwiniensis AND THE WOODROACH Cryptocercus darwini 下载免费PDF全文
Franziska Wende Martina Meyering‐Vos Klaus H. Hoffmann 《Archives of insect biochemistry and physiology》2016,91(2):88-108
Allatostatins with the C‐terminal ending Tyr/Phe‐Xaa‐Phe‐Gly‐Leu/Ile‐amide (FGLa/ASTs) are widespread neuropeptides with multiple functions. The gene encoding the FGLa/AST polypeptide precursor was first isolated from cockroaches and since then could be identified in many insects and crustaceans. With its strictly conserved regions in combination with variable regions the gene seems to be a good candidate for phylogenetic analyses between closely and distantly related species. Here, the structure of the FGLa/AST gene of the most primitive termite, the giant northern termite Mastotermes darwiniensis Froggatt, was identified. The FGLa/AST gene of the woodroach Cryptocercus darwini was also determined. Precursor sequences of both species possess the general organization of dictyopteran FGLa/AST precursors containing 14 putative FGLa/AST peptides. In M. darwiniensis, only 11 out of the 14 FGLa/AST‐like peptides possess the C‐terminal conserved region Y/FXFGL/I/V/M and four of the putative peptide structures are not followed by a Gly residue that would lead to nonamidated peptides. Phylogenetic analyses show the high degree of similarity of dictyopteran FGLa/AST sequences. The position of termites, nested within the Blattaria, confirms that termites have evolved from primitive cockroaches. 相似文献
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M. HARRY V. ROY A. MERCIER A. LIVET E. GARNIER N. BOUSSERRHINE C. DEMANCHE 《Molecular ecology resources》2007,7(1):121-123
We report here on the development of six polymorphic microsatellite loci for Labiotermes labralis. This soil‐feeding species is restricted to the Neotropical rainforest and then could represent a major candidate for being a bio‐indicator of anthropic disturbance resulting in the forest fragmentation. The microsatellite loci were isolated and characterized using a microsatellite‐enriched genomic library. The primers were tested on a French Guyanese population of L. labralis, represented by the sampling of one soldier in 22 nests. The primers were also tested against nine species of the same Nasutitermitinae subfamily and were successfully amplified at five loci in Armitermes minutus. 相似文献
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Shengjie Liu Xiaobing Lin Jocelyn E. Behm Hao Yuan Petr Stiblik Jan obotník Jianmin Gan Shangwen Xia Xiaodong Yang 《Ecological Entomology》2019,44(6):762-770
1. While it is clear that land‐use change significantly impacts the taxonomic dimension of soil biodiversity, how the functional dimension responds to land‐use change is less well understood. 2. This study examined how the transformation of primary forests into rubber tree monocultures impacts individual termite species and how this change is reflected in termite taxonomic and functional α‐diversity (within site) and β‐diversity (among sites). 3. Overall, individual species responded strongly to land‐use change, whereby only 11 of the 27 species found were able to tolerate both habitats. These differences caused a 27% reduction in termite taxonomic richness and reduced taxonomic β‐diversity in rubber plantations compared with primary forests. The study also revealed that the forest conversion led to a shift in some termite species with smaller body size, shorter legs and smaller mandibular traits. Primary forests exhibited higher functional richness and functional β‐diversity of termite species, indicating that functional traits of termite species in rubber plantations are more evenly distributed. 4. The present study suggests that forest conversion does not merely decrease taxonomic diversity of termites, but also exerts functional trait filtering within some termite species. The results affirm the need for biodiversity assessments that combine taxonomic and functional indicators when monitoring the impact of land‐use change. 相似文献
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Following a short swarming flight, winged adults of the Formosan subterranean termite, Coptotermes formosanus lose their wings and form tandem pairs. These dealates or primary reproductives then form incipient colonies. Topical application of 5 microg of the non-steroidal ecdysone agonist RH-0345 (halofenozide) in 0.1 microl DMSO to the primary reproductives during the 2000 season resulted in significant reduction in the number of eggs laid. There was however complete recovery of the treated females. Apparently the non-treated partner removed the treatment chemical while grooming indicating oral activity. In 2001 both topical application as well as feeding methods were tried. Significant effects were observed only in the topical treatment group, perhaps because of inconsistency in feeding. In this group, total progeny, the number of ovarioles in ovaries and the size of the female's corpora allata (CA) were all significantly reduced. Ultrastructure of the CA of treated females showed extensive vacuolation near the surface of the gland. The experiment was repeated in 2002 using both topical application and an improved oral feeding method. Whereas there was apparent recovery in the topically treated group after 90 days, the oral treatment was more persistent in its effect perhaps due to a higher amount of halofenozide consumed during feeding. 相似文献
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Methanogenic Archaea are often encountered in habitats that are not entirely anoxic in space or time. Recent biochemical and genomic studies have revealed the capacity of methanogens to reduce molecular oxygen. O(2) reduction by Methanobrevibacter species was investigated. Cell suspensions incubated in agar tubes under a headspace of H(2)-CO(2) and increasing concentrations of O(2) formed a distinct growth band, which coincided with the oxic-anoxic interface and indicated that the influx of O(2) into the band was balanced by its consumption. However, in batch cultures methanogenesis ceased as soon as traces of O(2) were added. Focusing on Methanobrevibacter cuticularis, a species colonizing the microoxic gut epithelium of termites, a diffusion-limited setup was used that allowed the exposure of dense cell suspensions to controlled O(2) fluxes. Here, Methanobrevibacter cuticularis was capable of simultaneous CH(4) production and O(2) consumption. Low O(2) fluxes (10% of the CH(4) production rate) had virtually no influence on methanogenesis [4.5 micromol CH(4) (mg dry wt)(-1) h(-1)], whereas higher O(2) fluxes (up to 30% of the initial CH(4) production rate) caused a reversible decrease in methanogenesis, which was accompanied by a reversible, partial conversion of coenzyme F(420) to factor F(390). The maximum O(2) reduction rate [4.8 micromol O(2) (mg dry wt)(-1) h(-1)] that could be maintained over extended time periods (>30 min) was similar to the CH(4) production rate under anoxic conditions. 相似文献