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291.
Ierecê ML Rosa Rômulo RN Alves Kallyne M Bonifácio José S Mourão Frederico M Osório Tacyana PR Oliveira Mara C Nottingham 《Journal of ethnobiology and ethnomedicine》2005,1(1):1-15
From a conservationist perspective, seahorses are threatened fishes. Concomitantly, from a socioeconomic perspective, they represent a source of income to many fishing communities in developing countries. An integration between these two views requires, among other things, the recognition that seahorse fishers have knowledge and abilities that can assist the implementation of conservation strategies and of management plans for seahorses and their habitats. This paper documents the knowledge held by Brazilian fishers on the biology and ecology of the longsnout seahorse Hippocampus reidi. Its aims were to explore collaborative approaches to seahorse conservation and management in Brazil; to assess fishers' perception of seahorse biology and ecology, in the context evaluating potential management options; to increase fishers' involvement with seahorse conservation in Brazil. Data were obtained through questionnaires and interviews made during field surveys conducted in fishing villages located in the States of Piauí, Ceará, Paraíba, Maranhão, Pernambuco and Pará. We consider the following aspects as positive for the conservation of seahorses and their habitats in Brazil: fishers were willing to dialogue with researchers; although captures and/or trade of brooding seahorses occurred, most interviewees recognized the importance of reproduction to the maintenance of seahorses in the wild (and therefore of their source of income), and expressed concern over population declines; fishers associated the presence of a ventral pouch with reproduction in seahorses (regardless of them knowing which sex bears the pouch), and this may facilitate the construction of collaborative management options designed to eliminate captures of brooding specimens; fishers recognized microhabitats of importance to the maintenance of seahorse wild populations; fishers who kept seahorses in captivity tended to recognize the condtions as poor, and as being a cause of seahorse mortality. 相似文献
292.
Andrew ML Lever 《Retrovirology》2006,3(1):1-4
The 2006 M Jeang Retrovirology Prize for HIV research has been awarded to Dr Joe Sodroski 相似文献
293.
Karma Nanglu Selina R. Cole David F. Wright Camilla Souto 《Biological reviews of the Cambridge Philosophical Society》2023,98(1):316-351
Deuterostomes are the major division of animal life which includes sea stars, acorn worms, and humans, among a wide variety of ecologically and morphologically disparate taxa. However, their early evolution is poorly understood, due in part to their disparity, which makes identifying commonalities difficult, as well as their relatively poor early fossil record. Here, we review the available morphological, palaeontological, developmental, and molecular data to establish a framework for exploring the origins of this important and enigmatic group. Recent fossil discoveries strongly support a vermiform ancestor to the group Hemichordata, and a fusiform active swimmer as ancestor to Chordata. The diverse and anatomically bewildering variety of forms among the early echinoderms show evidence of both bilateral and radial symmetry. We consider four characteristics most critical for understanding the form and function of the last common ancestor to Deuterostomia: Hox gene expression patterns, larval morphology, the capacity for biomineralization, and the morphology of the pharyngeal region. We posit a deuterostome last common ancestor with a similar antero-posterior gene regulatory system to that found in modern acorn worms and cephalochordates, a simple planktonic larval form, which was later elaborated in the ambulacrarian lineage, the ability to secrete calcium minerals in a limited fashion, and a pharyngeal respiratory region composed of simple pores. This animal was likely to be motile in adult form, as opposed to the sessile origins that have been historically suggested. Recent debates regarding deuterostome monophyly as well as the wide array of deuterostome-affiliated problematica further suggest the possibility that those features were not only present in the last common ancestor of Deuterostomia, but potentially in the ur-bilaterian. The morphology and development of the early deuterostomes, therefore, underpin some of the most significant questions in the study of metazoan evolution. 相似文献
294.
Gabriel de Souza Colombo Isis Viana Mendes Betúlia de Morais Souto Cristine Chaves Barreto Luana Assis Serra Eliane Ferreira Noronha Nádia Skorupa Parachin João Ricardo Moreira de Almeida Betania Ferraz Quirino 《Letters in applied microbiology》2022,74(6):941-948
The current climate crisis demands replacement of fossil energy sources with sustainable alternatives. In this scenario, second-generation bioethanol, a product of lignocellulosic biomass fermentation, represents a more sustainable alternative. However, Saccharomyces cerevisiae cannot metabolize pentoses, such as xylose, present as a major component of lignocellulosic biomass. Xylose isomerase (XI) is an enzyme that allows xylose consumption by yeasts, because it converts xylose into xylulose, which is further converted to ethanol by the pentose-phosphate pathway. Only a few XI were successfully expressed in S. cerevisiae strains. This work presents a new bacterial XI, named GR-XI 1, obtained from a Brazilian goat rumen metagenomic library. Phylogenetic analysis confirmed the bacterial origin of the gene, which is related to Firmicutes XIs. After codon optimization, this enzyme, renamed XySC1, was functionally expressed in S. cerevisiae, allowing growth in media with xylose as sole carbon source. Overexpression of XySC1 in S. cerevisiae allowed the recombinant strain to efficiently consume and metabolize xylose under aerobic conditions. 相似文献
295.
Arboreal primates use loud vocalisations to transmit information in densely vegetated habitats. These vocalisations are likely to show adaptations to increase their propagation and to transmit information. Golden-backed uakaris, Cacajao melanocephalus, emit a loud vocalization termed the “tchó” call, which seems to function as a contact call and encodes information on the individual signaler and behavioural context. Because the call is often used for communication over relatively large distances, we were interested in its propagation in the wild. The aim of the present study was to investigate the degradation patterns of the tchó call in the flooded igapó forest. We examined via playback experiments how the acoustic parameters of this call changed with increasing distance from the playback speaker. We broadcast 12 tchó calls and rerecorded them along a transect at distances of 10, 20, 40, 80 and 160?m from the speaker in two igapó forest patches in Jaú National Park, Amazonas, Brazil. At 160?m from the speaker, the tchó call degraded in both patches and was barely recordable. Up to a distance of 80?m, the bandwidth and number of harmonics in the call decreased with increasing distance, while the lowest frequency increased. The highest frequency (HF) did not gradually decrease with increasing distance. However, when we compared the HF at distances of 10 and 80?m, we could see a clear decrease in this parameter. Call duration increased compared with the broadcast signal up to 40?m because of reverberation, but decreased at 80?m as the weaker echoes of the call attenuated. These changes may reveal information about the signaler’s distance during signal transmission. The frequency of maximum energy (FME) of the tchó call decreased significantly when comparing recordings made at 10 and 80?m. Nevertheless, it did not show a consistent and gradual decrease with increasing rerecording distance (at least up to 80?m). FME remained relatively stable (±50?Hz on average, at least up to 80?m) when compared to the other call parameters, suggesting that the tchó call may be adapted to transmit information with some efficiency throughout the igapó forest. 相似文献
296.
Rodrigo B. de Souto Lima Pedro A. Oliveira Adriano G. Chiarello 《Mammalian Biology》2010,75(6):538-546
Chaetomys is a poorly known, monotypic genus of tree porcupine threatened with extinction due to deforestation and habitat fragmentation. Its nocturnal habit, relatively restricted distribution and low level of activity have conspired for decades against detailed field studies. Here the diet of the species in restinga forests is described for the first time. Restinga is a subtype of lowland Atlantic forest occurring on sandy soils close to the Atlantic littoral in Brazil. Three radio-collared females were monitored for 12 months between March 2005 and February 2006. Leaves were the most heavily consumed dietary item, varying from 71.9% to 75.4% of the diet of each individual, followed by flowers (7.7% - 15.7%) and fruits (0 - 1.4%). Animals fed on 57 trees from 14 species, with a higher concentration on Pera glabrata (49.8%) and Tapiriria guianensis (22.7%). Pera glabrata is locally abundant and widely distributed in the Atlantic forest. Each individual consumed a smaller subset of plant species (4-10 species/individual) and shared only the two most important tree species (P. glabrata and T. guianensis). Results corroborate previous studies indicating that Chaetomys is a folivore, perhaps the most folivorous amongst the Erethizontidae. Since the most consumed plant species are relatively common and widespread, Chaetomys might thrive in a broader range of habitats than previously suspected, including secondary forests. 相似文献
297.
298.
EGF receptor signaling in prostate morphogenesis and tumorigenesis. 总被引:12,自引:0,他引:12
The growth and differentiation of the prostate gland are largely dependent on extracellular signaling factors. In addition to androgens, many polypeptide growth factors function through autocrine or paracrine networks. The paracrine interaction between stromal and epithelial cells is critical for androgen regulation, morphogenesis, epithelial cell proliferation, and secretory differentiation. Efforts to identify the essential growth factors and studies on their effects have been prompted by the fact that prostate cells in culture need substances other than androgens for proliferation. In this context, transforming growth factor-alpha and epidermal growth factor, among others, have been studied extensively. Recent advances have suggested that these EGF receptor (EGFR) ligands play roles not only during glandular development but also during neoplastic transformation and tumor progression. The cell responses most relevant to the role of this receptor signaling are both mitogenesis and cell motility. The aim of the review is to provide an overview of current knowledge about EGFR and its ligands in the organogenesis and tumorigenesis of the prostate gland. 相似文献
299.
Dr. Andréa V. Machado Dr. Luana R. O. Menezes Dr. Adilson A. M. Santana Dr. Maria N. Marques Dr. Adriana K. de Lima Dr. Amanda Cano Prof. Dr. Patrícia Severino Prof. Dr. Eliana B. Souto Prof. Dr. Juliana C. Cardoso 《化学与生物多样性》2023,20(10):e202300083
This work describes a new hair dyeing methodology using a chemical reaction between geniposide, an iridoid glycoside extracted from the fruit of Genipa americana (geniposide extract, GE) and the amine group of hair keratin. The influence of reaction conditions (pH, temperature, and extract concentration) on the staining of hair fibers, color development, fiber morphology, and mechanical hair properties of black and white human hair samples, was evaluated before and after GE dyeing treatment. Eye contact safety of GE was also studied using HET-CAM. The treatment of white hair fibers using GE at 20 mg mL−1, temperature of 80 °C and pH 5.5 presented the greatest color change (ΔE=54.0). The higher pH influence was observed at pH 10.0 on white hair tresses (ΔE=6.8), using an GE concentration of 20 mg mL−1 and room temperature (25 °C). Treated samples showed marked changes on mechanical and morphological properties. The HET-CAM did not show any change, thus demonstrating that using GE is safe. In conclusion, the temperature and concentration of the extract were the variables that mostly influenced the color and hair damage. A new approach for hair dyeing was established where iridoids may potentially be useful as a natural hair dyeing. 相似文献
300.
Carlos F. Campos Boscolli B. Pereira Edimar O. de Campos-Junior Eduardo F. Sousa Henrique N. Souto Sandra Morelli 《Genetics and molecular biology》2015,38(4):507-512
Pollutants have adverse effects on human health and on other organisms that inhabit
or use water resources. The aim of the present study was to assess the environmental
quality of three watercourses in Monte Carmelo, MG, Brazil, using the micronucleus
test on Tradescantia. For each treatment, 15 plants were exposed to
water samples for 24 h. The control group was exposed to formaldehyde (0.2%) and the
negative control to Hoagland solution. Subsequently the plants were placed in
Hoagland solution for 24 h to recover. Cells were stained with 2% acetic carmine and
examined by light microscopy. Three hundred tetrads were analyzed per slide. The
frequency of genotoxic alterations was expressed as the number of micronuclei per 100
tetrads, and the groups were compared by ANOVA. At all sample sites for each
watercourse significant genotoxicity indices were observed. The results suggest that
in the Mumbuca creek, the current situation of effluent discharge should be
reconsidered by the municipal environmental authorities. The increase in micronucleus
frequency denoted for water samples of the Mumbuca creek, Lambari river and Perdizes
river emphasizes the need to adopt environmental vigilance strategies, such as
biological monitoring. 相似文献