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241.
R. Hanus A. Luxová J. Šobotník B. Kalinová P. Jiroš J. Křeček T. Bourguignon C. Bordereau 《Insectes Sociaux》2009,56(2):111-118
We studied the post-flight behavior and sex attraction in imagoes of the termite Prorhinotermes simplex (Rhinotermitidae, Prorhinotermitinae). Pairing is mediated by the secretion from tergal glands, exposed by females in a calling
posture and highly attractive to males. Analysis of extracts of these glands by means of gas chromatography with electroantennographic
detection indicated a chromatographic area corresponding to an intense physiological response of males. The retention characteristics
of this area proved to be identical with those of (3Z,6Z,8E)-dodeca-3,6,8-trien-1-ol. Electroantennographic and behavioral assays revealed that units of picograms of the compound represent
a stimulus qualitatively and quantitatively equivalent to one female tergal gland. Thus, we hypothesize that (3Z,6Z,8E)-dodeca-3,6,8-trien-1-ol is a major component of the female sex pheromone in P. simplex. 相似文献
242.
Enzyme immunosorbent assays were used to measure cyclic nucleotide concentrations in homogenates of salivary glands from partially fed female Dermacentor variabilis. The adenylyl cyclase activator forskolin (100 μM) increased homogenate cGMP concentrations greater than three-fold over controls. Competitive inhibition of nitric oxide synthase with 1 mM l-NMMA, an l-arginine analog, demonstrated that crosstalk occurs downstream of nitric oxide synthesis. Forskolin-stimulated synthesis of cGMP was diminished 58% by the soluble guanylyl cyclase inhibitor ODQ (2 μM). The protein kinase A selective inhibitor Rp-cAMPS (50 μM) inhibited forskolin-stimulated cGMP by 49%. Whole glands treated with 10 μM dopamine increased cGMP levels two-fold in the presence of 1 mM IBMX. Treatment of whole salivary glands with equimolar concentrations of 8-Br-cAMP and 8-Br-cGMP produced no greater fluid uptake than in glands treated with 8-Br-cGMP alone, suggesting that cAMP and cGMP share a downstream target. The protein kinase G-selective inhibitor Rp-8-pCPT-cGMPS (100 μM) impeded 10 mM 8-Bromo-cGMP-stimulated gland weight increases. Pretreatment with verapamil, a Ca2+ channel blocker, attenuated cyclic nucleotide-stimulated fluid uptake indicating that whole gland fluid changes are dependent on extracellular Ca2+. Together, our data suggest that cGMP production is mediated in part by cAMP-dependent activation of soluble guanylyl cyclase. Experiments measuring changes in whole salivary gland weight support the hypothesis that cAMP and cGMP signaling cascades have a common target and that cyclic nucleotide-stimulated fluid movement is dependent on Ca2+ influx. 相似文献
243.
244.
As for other rodents, peri-anal glands are well developed in the crested porcupine Hystrix cristata. Their waxy secretion has a peculiar odour, usually perceivable around the dens. Male African H. africaeaustralis use this secretion to mark feeding sites in captivity, but its function in H. cristata has never been studied yet. Through live-trapping in Central Italy, we sampled gland contents of 33 freely living crested porcupines (19 males and 14 females), and, in 5 animals, 2-3 subsequent collections were made at different times.GC-MS analyses showed that the secretion volatile component is a complex mixture, mainly constituted by aliphatic compounds. The principal constituents were saturated and unsaturated γ-lactones, macrolactones, primary alcohols and fatty acids. The composition was similar between sexes, but for two compounds (nonadecan-1-ol and a compound tentatively identified as 16-methyl oxacyclohexadecan-2-one) that were significantly more frequent in males than in females.We compared the squared Euclidean distances of the relative abundances of constituents in all possible couple of specimens, and found that the average distance between males and females was significantly higher than the distance between males, but significantly lower than the distance between females. We hypothesized that, although all the females were adult, this variability might be due to physiological differences between individuals (e.g. reproductive status). Using the same approach, we found that the chemical profiles of different individuals (inter-individual variability) was greater than intra-individual variability, suggesting that the peri-anal secretions may play a role in individual recognition. 相似文献
245.
Several recent studies demonstrated that development, function and remodelling of mammary glands involved multipotent cells,
but no specific molecular markers for mammary epithelial stem cells were revealed. These studies principally concerned human
and mouse mammary tissue, but mammary stem cells could be a valuable tool in agricultural production and bioengineering in
farm animals. The Musashi-1 (Msi 1) gene encodes an RNA binding protein, which is likely to be associated with self-renewal
of neural, intestinal and mammary progenitor cells and is believed to influence the Notch signalling pathway. In this study Musashi-1 expression was detected using immunohistochemistry and in situ hybridisation
analysis on mammary glands of ewes at different developmental stages. The protein expression was observed in the epithelial
cells at all stages examined. In situ hybridization analysis showed that Msi 1 mRNA has an expression pattern similar to the
encoded protein, with positive staining in both nuclei and cytoplasm of ductal, secretory and stromal cells. Ultrastructural
in situ analysis confirmed the nuclear and cytoplasmatic expression of Msi. Quantitative analysis of Msi 1 gene expression
showed a strong correlation with that of Ki-67, that is a marker of cell proliferation. This is the first report outlining
expression of Msi 1 in ovine mammary glands during a complete cycle of lactation. 相似文献
246.
The female postabdomen of Agathiphaga vitiensis terminates in a telescope‐type extensible oviscapt with an apial ‘oviscapt probe’ composed of fused segments behind VIII. Exceptionally within the Lepidoptera two pairs of long ‘anterior apophyses’ arise from segment VIII, from the dorsum and venter. Agathiphaga has the most elaborate postabdominal musculature recorded from female Lepidoptera, comprising 24 muscle sets of which nine may be family autapomorphies. Apophysis musculature does not permit unambiguous homologizing of the single anterior apophysis in Lepidoptera–Glossata with either the dorsal or ventral pair in Agathiphaga, but is compatible with an interpretation of the glossatan anterior apophyses as a composite formation. Nine muscle sets shared with rhyacophilid caddisflies are ascribed to the amphiesmenopteran ground plan. The spermathecal duct represents an intermediate stage between the simple type present in Micropterigidae and the ‘two‐compartment type’ characteristic of almost all other Lepidoptera. The spermatheca has no lagena. The bursa copulatrix is small and simple. Accessory glands are very large, simple sacs. There are 40 + ovarioles per ovary. A terminal cloaca is extremely short. The numerous ovarioles potentially support a sister‐group relationship between Agathiphagidae and all other Lepidoptera, whereas the spermathecal duct histology supports the alternative conservative placement of the family as sister group of all nonmicropterigid Lepidoptera. © 2010 The Linnean Society of London, Zoological Journal of the Linnean Society, 2010, 159 , 905–920. 相似文献
247.
JAN ŠOBOTNÍK THOMAS BOURGUIGNON ROBERT HANUS FRANTIŠEK WEYDA YVES ROISIN 《Biological journal of the Linnean Society. Linnean Society of London》2010,99(4):839-848
The soldier caste represents the most conspicuous realization of termite eusociality, characterized by an extreme anatomical, behavioural, and physiological specialization. Numerous strategies have evolved in soldiers, including extreme adaptations such as self‐sacrifice by autothysis. In the present study, we investigated the structure and function of defensive glands in Glossotermes oculatus soldiers aiming to understand their use in combat. Three glands are involved in defence: labral, frontal, and labial glands. Mandibles are used to bite the enemy, whereas the secretions of labral and labial glands are discharged into the wound. A striking characteristic of G. oculatus is the lack of the frontal pore; the secretion of the frontal gland is discharged by a rupture of the body wall. We hypothesized that this self‐sacrifice is an efficient way of blocking a gallery under attack. A similar development of the frontal gland occurs in Serritermes serrifer, which supports the close relationship between the two genera inferred from morphological and genetic analyses. © 2010 The Linnean Society of London, Biological Journal of the Linnean Society, 2010, 99 , 839–848. 相似文献
248.
This study of the sand goby Pomatoschistus minutus, a nest‐holding fish with paternal care, focused on gonadal investment among males of different sizes collected early and late in the breeding season. All males caught at the nest had breeding colour, whereas trawl‐caught fish consisted of males both with and without colour. The absence or presence of breeding colour was a good predictor of testes investment. Compared to males with breeding colour, males without colour were smaller in body size but had extraordinarily large testes. In absolute terms, testes mass of males without breeding colour was on average 3·4 times greater than those of males with breeding colour. Since small colourless males are known to reproduce as sneaker males, this heavy investment in testes probably reflects that they are forced to spawn under sperm competition. Contrary to testes size, sperm‐duct glands were largest among males with breeding colour. These glands produce mucins used for making sperm‐containing mucous trails that males place in the nest before and during spawning. Since both sneakers and nest‐holders potentially could benefit from having large glands, this result is intriguing. Yet, high mucus production may be more important for nest‐holders, because it also protects developing embryos from infections. There was no significant effect of season on body size, testes or sperm‐duct glands size, but colourless males tended to be less common late in the season. Possibly this may indicate that individual small colourless males develop into their more colourful counterparts within the breeding season. 相似文献
249.
Ladawan Wasinpiyamongkol Sirilaksana Patramool Natthanej Luplertlop Pornapat Surasombatpattana Souleymane Doucoure François Mouchet Martial Séveno Franck Remoue Edith Demettre Jean‐Paul Brizard Patrick Jouin David G. Biron Frédéric Thomas Dorothée Missé 《Proteomics》2010,10(10):1906-1916
Mosquito‐transmitted pathogens pass through the insect's midgut (MG) and salivary gland (SG). What occurs in these organs in response to a blood meal is poorly understood, but identifying the physiological differences between sugar‐fed and blood‐fed (BF) mosquitoes could shed light on factors important in pathogens transmission. We compared differential protein expression in the MGs and SGs of female Aedes aegypti mosquitoes after a sugar‐ or blood‐based diet. No difference was observed in the MG protein expression levels but certain SG proteins were highly expressed only in BF mosquitoes. In sugar‐fed mosquitoes, housekeeping proteins were highly expressed (especially those related to energy metabolism) and actin was up‐regulated. The immunofluorescence assay shows that there is no disruption of the SG cytoskeletal after the blood meal. We have generated for the first time the 2‐DE profiles of immunogenic Ae. aegypti SG BF‐related proteins. These new data could contribute to the understanding of the physiological processes that appear during the blood meal. 相似文献
250.
The recretohalophyte with specialized salt-secreting structures including salt glands and salt bladders can secrete salt from
their bodies and easily adapt themselves to many kinds of salt habitats. Salt glands and salt bladders, arose from dermatogen
cells, are excretory organs specially adapted for dealing with ionic homeostasis in the cells of recretohalophytes. The main
function of salt glands or salt bladders is to secrete excess ions that invade the plant. The structures of salt glands or
salt bladders differ among plant species. In addition to structural differences, salt glands also differ in their secretion
abilities. In this review, we mainly focus on recent progress in the mechanism of salt excretion of salt glands and salt bladders,
and in particular, emphasize the vesicle-mediated secretion systems from the vacuole to the plasmalemma and the possibly involved
membrane-bound translocating proteins for salt secretion of plant gland secretory cell. 相似文献