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111.
Nestboxes are known to increase clutch size, enhance breeding success and affect the social mating system of several cavity nesters. Although in recent years various cavity nesters have been studied in nestboxes in South America, the effects of boxes on the biology of the study species are unknown. We evaluated the effects of nestboxes on the breeding biology and social mating system of Southern House Wrens Troglodytes aedon bonariae by comparing birds breeding in nestboxes and tree cavities in two cattle ranches in Buenos Aires Province, Argentina. Southern House Wrens nesting in boxes had higher breeding success but, contrary to studies on the temperate zone, we did not find differences in clutch size between Wrens breeding in nestboxes and tree cavities. The main causes of nest failure in tree cavities were nest predation and flooding of the cavity (70 and 23% of the failures, respectively) while in nestboxes predation and desertion were the most important causes of failure (38 and 34% of the failures, respectively). The social mating system of Southern House Wrens is monogamy with biparental care, and neither was affected by the boxes. Males did not attract secondary females to additional nestboxes; however, nestboxes are safer breeding sites than tree cavities, and females seemed to prefer males with nestboxes on their territory. These results suggest that nest quality alone might be not enough for secondary females to accept polygyny. 相似文献
112.
A. terreus isolates isolated from some bakery products, corn and rice were found to be able to produce territrems. 90% of theA. terreus isolated from bakery products were able to produce territrem A, with a mean of 0.09 ppm, while 80% ofA. terreus isolates produce territrem B with a mean of 0.24 ppm. On the other hand 31.8% of the isolates ofA. terreus from corn were able to produce territrem A with a mean of 0.44 ppm. ConcerningA. terreus isolates from rice, 66.7% were found to produce territrem A, with a mean of 5.28 ppm, and 77.8% of the isolates produced
territrem B with a mean of 1.79 ppm. 相似文献
113.
Richard J Dobson Patricia B Munroe Mark J Caulfield Mansoor AS Saqi 《BMC bioinformatics》2006,7(1):217-9
Background
There has been an explosion in the number of single nucleotide polymorphisms (SNPs) within public databases. In this study we focused on non-synonymous protein coding single nucleotide polymorphisms (nsSNPs), some associated with disease and others which are thought to be neutral. We describe the distribution of both types of nsSNPs using structural and sequence based features and assess the relative value of these attributes as predictors of function using machine learning methods. We also address the common problem of balance within machine learning methods and show the effect of imbalance on nsSNP function prediction. We show that nsSNP function prediction can be significantly improved by 100% undersampling of the majority class. The learnt rules were then applied to make predictions of function on all nsSNPs within Ensembl. 相似文献114.
Wuelton M Monteiro Fernando FA Val André M Siqueira Gabriel P Franca Vanderson S Sampaio Gisely C Melo Anne CG Almeida Marcelo AM Brito Henry M Peixoto Douglas Fuller Quique Bassat Gustavo AS Romero Oliveira Maria Regina F Lacerda Marcus Vinícius G 《Memórias do Instituto Oswaldo Cruz》2014,109(5):553-568
115.
MATÍAS MORA ADRIANA ITATÍ OLIVARES ALDO I. VASSALLO 《Biological journal of the Linnean Society. Linnean Society of London》2003,78(1):85-96
Morphological analysis of the skull of the subterranean rodent Ctenomys , a highly speciose genus which uses both claws and teeth when digging, shows that for a broad range of species size, scaling was associated with both variation and maintenance of shape. Our results show that the angle of incisor procumbency (AIP), a character largely viewed as an adaptation to digging with teeth, is highly variable. We found a non-significant relationship between AIP and basicranial axis (basioccipital + basisphenoid) length, a measure of overall skull size. Accordingly, both small and large Ctenomys species possess either high or low AIP. A significant relationship between AIP and diastema length, given the rostral allometry seen in Ctenomys , suggests that hypermorphosis to a certain extent influences AIP. However, the roots of the incisor are lateral to those of the cheek teeth and their position may thus shift freely. This observation supports the notion that skull structural design, and to a certain extent rostral allometry, underlies variation in AIP. On the other hand, the positive allometry of incisor width and thickness indicates that, in larger species, proportionately powerful incisors are able to resist greater bending forces. We found that the out-lever arm of the jaw adductor muscles scales with positive allometry against basicranial axis length. However, we found an isometric relationship between in- and out-lever arms. In this case, conservation of skull proportions, regardless of variation in size, is a feature possibly related to the maintenance of an effective tooth digging capability. Functional and ecological data are discussed when assessing the implications of size and shape variation in the skull of Ctenomys . © 2003 The Linnean Society of London. Biological Journal of the Linnean Society , 2003, 78 , 85−96. 相似文献
116.
JORGE DOÑA JAIME POTTI IVÁN DE LA HERA GUILLERMO BLANCO OSCAR FRÍAS ROGER JOVANI 《Ecological Entomology》2017,42(4):492-499
1. The consequences of symbiont transmission strategies are better understood than their adaptive causes. 2. Feather mites are permanent ectosymbionts of birds assumed to be transmitted mainly vertically from parents to offspring. The transmission of Proctophyllodes doleophyes Gaud (Astigmata, Proctophyllodidae) was studied in two European populations of pied flycatchers, Ficedula hypoleuca Pallas (Passeriformes, Muscicapidae). 3. The vertical transmission of this mite species is demonstrated here with an acaricide experiment. This study also compared (for two distant populations during 4 years) patterns in reductions in mite intensity in adult birds, from egg incubation to chick‐rearing periods, with the predictions of three hypotheses on how host survival prospects and mite intraspecific competition might drive feather mites' transmission strategy. 4. The results are in agreement with previous studies and show that feather mites transmit massively from parents to chicks. 5. The magnitude of the transmission was closer to that predicted by the hypothesis based on intraspecific competition, while a bet‐hedging strategy is also partially supported. 相似文献
117.
118.
M Morgan Conn Joe Kappock Dale Drueckhammer Richard Cammack Dennis Hall Tony Cass Jon D Stewart Graham RL Cousins Jeremy KM Sanders Sabine Flitsch Philip AS Lowden Richard Newman 《Current opinion in chemical biology》1999,3(6):631
A selection of interesting papers that were published in the two months before our press date in major journals most likely to report significant results in chemical biology. 相似文献
119.
120.
F. R. SCARANO FLS H. M. DUARTE G. RÔÇAS S. M. B. BARRETO E. F. AMADO F. REINERT T. WENDT A. MANTOVANI H. R. P. LIMA C. F. BARROS 《Botanical journal of the Linnean Society. Linnean Society of London》2002,140(4):391-401
The clonal tank-bromeliad Aechmea bromeliifolia (Rudge) Baker was found in four different habitats in a restinga (vegetation mosaic on sandy coastal plains), of south-eastern Brazil. These habitats (swamp forest, dry forest, dry shrubland and herbaceous marsh) lie within a few hundred metres of each other along a gradient extending inland from the coast, and differ markedly in terms of light and flood regime. We compared ramet morphology, leaf anatomy and physiology, and population parameters to examine the amplitude of trait variation of this widespread species in the studied restinga. This integrated approach allowed us to examine which variation conferred acclimation and which was merely a stress symptom. A . bromeliifolia showed site-specific differences in abundance, distribution, rosette size and shape, leaf anatomical arrangement and photochemical efficiency (potential quantum yield; F v / F m ) during the day. Most of the variation found seemed to be related to the interaction of light and flooding. The lowest number and size of ramets at the exposed, dry shrubland was matched by a marked leaf photoinhibition, which suggested poor acclimation to local levels of light intensity and limited water supply. In the other habitats, the morpho-physiological parameters measured suggested adequate foraging behaviour and site acclimation. © 2002 The Linnean Society of London, Botanical Journal of the Linnean Society, 2002, 140 , 391-401. 相似文献