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991.
992.
Peter J. Koehler Stanley Finger Marco Piccolino 《Journal of the history of biology》2009,42(4):715-763
During the mid-18th century, when electricity was coming into its own, natural philosophers began to entertain the possibility
that electricity is the mysterious nerve force. Their attention was first drawn to several species of strongly electric fish,
namely torpedoes, a type of African catfish, and a South American “eels.” This was because their effects felt like those of
discharging Leyden jars and could be transmitted along known conductors of electricity. Moreover, their actions could not
be adequately explained by popular mechanical theories. Many of the early documents supportive of the hypothesis of animal
electricity were associated with the Dutch colonies in South America. This article presents and examines those documents,
and shows how Dutch scientists on both sides of the Atlantic conducted experiments and communicated with each other in the
1750s and 1760s. It reveals the important roles played by inquisitive physicians and lovers of nature in South America, and
by natural philosophers and collectors of exotic specimens in the Netherlands—learned men who began to make a credible case
for animal electricity in some exciting places at a pivotal moment in time. 相似文献
993.
994.
995.
Vespasiano Borges Paiva Neto Luciano B. Reis Fernando L. Finger Raimundo S. Barros Carlos R. Carvalho Wagner C. Otoni 《In vitro cellular & developmental biology. Plant》2009,45(6):693-700
Using seedlings derived from the shoot apex of annatto (Bixa orellana L. cv. Bico-de-Pato) we observed the rooting frequency of B. orellana, the number and length of roots and the rate of ethylene production during 30 d in culture. The rhizogenesis response was
affected by auxins (NAA or IBA) and by both the ethylene biosynthesis precursor 1-aminocyclopropane-1-carboxylic acid (ACC)
and the inhibitor 2-aminoethoxyvinylglycine (AVG). Auxin supplementation to the medium resulted in root induction, ethylene
production, and an undesirable callusing in the epidermal and cortical tissues. Irrespective of the presence of auxins, supplementing
the medium with ACC promoted ethylene biosynthesis and callusing, which resulted in increased cell proliferation mainly in
the cortical and vascular tissues, while the epidermis was mostly unaltered. In both ACC and auxin-supplemented medium, increased
ethylene production and callusing occurred, suggesting a synergistic effect between these two responses. ACC was capable of
inducing adventitious root formation, but the roots produced had a wrinkled appearance when compared to normal roots. Conversely,
AVG reduced ethylene production and callusing, while the epidermis, cortex, and inner tissues remained unaltered, regardless
of the presence of auxins. AVG was beneficial in these aspects, although its application led to a reduction in the number
of roots and in the average root length. In conclusion, it was not possible to establish a direct relation between ethylene
and rooting, but we hypothesize that, under the experimental conditions described, ethylene may enhance tissue sensitivity
to auxin. However, ethylene did not seem essential to the rhizogenesis process in annatto. 相似文献
996.
997.
998.
Débora D. S. Vogel Nancy N. Ortiz-Villatoro Noemi S. Araújo Márcia Jonathas Guimarães Marques Flavio Aimbire Fúlvio A. Scorza Carla A. Scorza Regiane Albertini 《Journal of biophotonics》2021,14(6):e202000500
Stroke is the main cause of death and functional disability. The available therapy affects only 5% of patients, and new therapeutic approaches have been constantly tested. Transcranial photobiomodulation (PBM) is promising for its neuroprotective effect on brain injuries. Thus, the present study investigated the PBM effects in an in vivo model of ischemic stroke induced by photothrombosis (PT). Five different groups of Wistar rats were submitted or not to a daily dose of fish oil or/and laser sessions for 2 months. The ischemia volume was evaluated by stereology; GFAP, Iba and NeuN by immunohistochemistry; TNF-α, IL-1β, IL-6, IL-10 and TGF-β by ELISA assay. PBM influenced both the lesion volume and the GFAP. Furthermore, PBM and Ω-3 or both reduced Iba RNAm. PBM reduced TNF-α, IL-1β, IL-6, brain damage, neuroinflammation and microglial activation, and it increased astroglial activity in peri-lesioned region after stroke. 相似文献
999.
Carlotta Granchi Isabella Caligiuri Eleonora Bertelli Giulio Poli Flavio Rizzolio Marco Macchia 《Journal of enzyme inhibition and medicinal chemistry》2017,32(1):1240-1252
Monoacylglycerol lipase is a serine hydrolase that plays a major role in the degradation of the endocannabinoid neurotransmitter 2-arachidonoylglycerol. A wide number of MAGL inhibitors are reported in literature; however, many of them are characterised by an irreversible mechanism of action and this behavior determines an unwanted chronic MAGL inactivation, which acquires a functional antagonism of the endocannabinoid system. The possible use of reversible MAGL inhibitors has only recently been explored, due to the lack of known compounds possessing efficient reversible inhibitory activities. In this work, we report a new series of terphenyl-2-methyloxazol-5(4H)-one derivatives characterised by a reversible MAGL-inhibition mechanism. Among them, compound 20b showed to be a potent MAGL reversible inhibitor (IC50?=?348?nM) with a good MAGL/FAAH selectivity. Furthermore, this compound showed antiproliferative activities against two different cancer cell lines that overexpress MAGL. 相似文献
1000.
Camila Eduardo Marinho Selma Maria Almeida Santos Simone Cristina Yamasaki Paulo Flavio Silveira 《Journal of comparative physiology. B, Biochemical, systemic, and environmental physiology》2009,179(5):635-642
To understand the role of peptidases in seminal physiology of Crotalus durissus terrificus, intra- and inter-seasonal activity levels of acid (APA), basic (APB), puromycin-sensitive (APN-PS) and puromycin-insensitive
neutral (APN-PI), cystyl (CAP), dipeptidyl-IV (DPPIV), type-1 pyroglutamyl (PAP-I) and prolyl-imino (PIP) aminopeptidases
as well as prolyl endopeptidase (POP) were evaluated in soluble (SF) and/or membrane-bound (MF) fractions of semen collected
from the ductus deferens of the male reproductive tract and from the posterior portion of the uterus. Seminal APB, PIP and
POP were detected in SF, while other peptidases were detected in SF and MF. Only the convoluted posterior uterus in winter
and autumn had semen. Relative to other examined peptidases, in general, APN-PI, APN-PS and APB activities were predominant
in the semen from the uterus and throughout the year in the semen from the ductus deferens, suggesting their great relevance
in the seminal physiology of C. d. terrificus. The levels of peptidase activities in the ductus deferens semen varied seasonally and were different from those of semen
in the uterus, suggesting that their modulatory actions on susceptible peptides are integrated to the male reproductive cycle
events and spermatozoa viability of this snake. 相似文献