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41.
Pinocytosis of macromolecules from the gut lumen is demonstrated for the first time in larval stages of invertebrates. Developing sea stars ( Patiria miniata ) and sea urchins ( Lytechinus pictus ) were incubated in seawater containing ferritin, which was detected in cell organelles by transmission electron microscopy. Pinocytotic uptake of ferritin by gut cells of Patiria could be detected as soon as the larval mouth opened before the esophagus, stomach and intestine could be distinguished from one another; in contrast, no pinocytosis was detected at the comparable developmental stage (the prism larva) of Lytechinus . Pinocytosis was first detected in developing Lytechinus in pluteus larvae, especially in the stomach and intestine. In gut cells of both kinds of echinoderm larvae, the ferritin progressed rapidly from coated pits at the luminal cell membrane to secondary lysosomes (e.g. this progression took only about 10 min in stomach cells of Patiria larvae). Phagocytosis from the gut lumen was never observed after latex beads or starch granules were fed to larvae of Patiria and Lytechinus . Moreover, there was no evidence of pinocytosis of ferritin or phagocytosis of large particles by epidermal cells of larvae of either species. 相似文献
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ANDREA HODGINS‐DAVIS STEVEN ROBERTS DIANE F. COWAN JELLE ATEMA MICHAEL BENNIE CARLA AVOLIO JACQUELIN DEFAVERI GABRIELE GERLACH 《Molecular ecology resources》2007,7(2):330-332
The American lobster (Homarus americanus), a commercially important benthic marine crustacean, is widely distributed along the continental shelf of the western North Atlantic. The population substructure of this species remains poorly understood despite its economic value. Informative markers are required to clarify relationships between local populations. To this end, we developed eight polymorphic short sequence repeats (SSR) for the American lobster, which were derived from expressed sequence tags. Additionally, we tested four SSRs previously identified for the Norway lobster (Nephrops norvegicus L.) for cross‐species utility; only one of these showed polymorphism. 相似文献
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ANDREA FERREIRA DA COSTA PABLO JOSÉ FRANCISCO PENA RODRIGUES MARIA DAS GRAÇAS LAPA WANDERLEY 《Botanical journal of the Linnean Society. Linnean Society of London》2009,159(1):163-181
The species related to Vriesea paraibica (Bromeliaceae, Tillandsioideae) have controversial taxonomic limits. For several decades, this group has been identified in herbarium collections as V. × morreniana, an artificial hybrid that does not grow in natural habitats. The aim of this study was to assess the morphological variation in the V. paraibica complex through morphometric analyses of natural populations. Two sets of analyses were performed: the first involved six natural populations (G1) and the second was carried out on taxa that emerged from the first analysis, but using material from herbarium collections (G2). Univariate ANOVA was used, as well as discriminant analysis of 16 morphometric variables in G1 and 18 in G2. The results of the analyses of the two groups were similar and led to the selection of diagnostic traits of four species. Lengths of the lower and median floral bracts were significant for the separation of red and yellow floral bracts. Vriesea paraibica and V. interrogatoria have red bracts; these two species are differentiated by the widths of the lower and median portions of the inflorescence and by scape length. These structures are larger in the former and smaller in the latter. Of the species with yellow floral bracts, V. eltoniana is distinguished by longer leaf blades and scapes and V. flava is characterized by its shorter sepal lengths. © 2009 The Linnean Society of London, Botanical Journal of the Linnean Society, 2009, 159 , 163–181. 相似文献
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PETER TYRER ROGER MULDER MIKE CRAWFORD GILES NEWTON‐HOWES ERIK SIMONSEN DAVID NDETEI NESTOR KOLDOBSKY ANDREA FOSSATI JOSEPH MBATIA BARBARA BARRETT 《World psychiatry》2010,9(1):56-60
Personality disorder is now being accepted as an important condition in
mainstream psychiatry across the world. Although it often remains unrecognized
in ordinary practice, research studies have shown it is common, creates considerable
morbidity, is associated with high costs to services and to society, and interferes,
usually negatively, with progress in the treatment of other mental disorders.
We now have evidence that personality disorder, as currently classified, affects
around 6% of the world population, and the differences between countries show
no consistent variation. We are also getting increasing evidence that some
treatments, mainly psychological, are of value in this group of disorders.
What is now needed is a new classification that is of greater value to clinicians,
and the WPA Section on Personality Disorders is currently undertaking this
task. 相似文献
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ANDREA B. WARD ELIZABETH L. BRAINERD† 《Biological journal of the Linnean Society. Linnean Society of London》2007,90(1):97-116
Within the ray-finned fishes, eel-like (extremely elongate) body forms have evolved multiple times from deeper-bodied forms. Previous studies have shown that elongation of the vertebral column may be associated with an increase in the number of vertebrae, an increase in the length of the vertebral centra, or a combination of both. Because the vertebral column of fishes has at least two anatomically distinct regions (i.e. abdominal and caudal), an increase in the number and relative length of the vertebrae could be region-specific or occur globally across the length of the vertebral column. In the present study, we recorded vertebral counts and measurements of vertebral aspect ratio (vertebral length/width) from museum specimens for 54 species representing seven groups of actinopterygian fishes. We also collected, from published literature, vertebral counts for 813 species from 14 orders of actinopterygian and elasmobranch fishes. We found that the number of vertebrae can increase independently in the abdominal and caudal regions of the vertebral column, but changes in aspect ratio occur similarly in both regions. These findings suggest that abdominal vertebral number, caudal vertebral number, and vertebral aspect ratio are controlled by separate developmental modules. Based on these findings, we suggest some candidate developmental mechanisms that may contribute to vertebral column patterning in fishes. Our study is an example of how comparative anatomical studies of adults can generate testable hypotheses of evolutionary changes in developmental mechanisms. © 2007 The Linnean Society of London, Biological Journal of the Linnean Society , 2007, 90 , 97–116. 相似文献
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ANDREA MUCCI LORENA GARITTA GUILLERMO HOUGH SOLEDAD SAMPAYO 《Journal of sensory studies》2005,20(1):28-34
The objective of this work was to compare a panel of blind assessors with one of sighted assessors in the discrimination of food products. Each panel had 20 screened and trained assessors. Five commercial food products were used: crackers, liver paste, powdered orange juice mix, Reggiano cheese and yogurt. Slight flavor and/or texture modifications were introduced for adequate discrimination difficulty. Each pair of products was tested by both panels using the triangle test and a scaled difference from control test. Numbers of correct answers for the triangle test were similar for both panels. There were minor differences between the panels in the difference from control test, due to the sighted panel having more training in the use of the scale. Overall the panels of trained blind and sighted assessors were equivalent in their performance. 相似文献
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