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11.
Digeneans of the family Campulidae occur exclusively in marine mammals, particularly in cetaceans. Their taxonomy is confused, being based on adult morphology only. We used a multivariate discriminant analysis of morphometric data to provide new evidence on the taxonomy of the Campulidae. Measurements of 217 specimens from 21 species of all seven genera of the family were taken. The percentage of specimens correctly assigned into their own species was 96.3%. The first three discriminant functions accounted for most of the variation between the species, which were grouped together in suprageneric groups along the first and the second function. The ordination pattern observed conforms partly with the established taxonomy of the Campulidae. Variation along the first discriminant function can be interpreted as a gradient of the vitelline extension and the maximum width to length ratio. This function separates three groups of species, corresponding to the Hunterotrematinae, Orthosplanchninae and Campulinae-Lecithodesminae. The last two subfamilies are separated along the second axis, the Lecithodesminae having longer bodies and suckers than the Campulinae. This study also provides some evidence at the generic and specific level. 相似文献
12.
Carles Campmajó Jordi Joan Cairó Anna Sanfeliu Esteve Martínez Salvador Alegret Francesc Gòdia 《Cytotechnology》1994,14(3):177-182
A flow injection anlytical system based on a gas diffusion membrane module for ammonia and an ammonium flow-through potentiometric detector has been set up for measurement of L-glutamine and ammonium ions in hybridoma cell cultures. The main feature of the system is that the same basic analytical concept and equipment is used in both measurements, the only difference being for the determination of L-glutamine, in which the sample flows through an immobilized glutaminase cartridge. The conditions to enable the performance of both analysis consecutively, avoiding potential interferences by unwanted deamination of other compounds in the samples, have been determined. Finally, the proposed system has been compared with reference analytical methods for batch hybridoma cell culture experiments. 相似文献
13.
The trimeric derivative of 16,16-dimethyl-15-dehydroprostaglandin B1 (termed tri-Calciphor), which protects tissues against ischemic damage, induced Ca2+ efflux and swelling in mitochondria in the absence of phosphate, Mg2+ and ATP. When glutamate/malate rather than succinate was the substrate, higher tri-Calciphor concentrations were required for the ionophoretic activity. Ca2+ efflux and mitochondrial swelling induced by tri-Calciphor were completely inhibited by ATP, phopsphate and Mg2+ added together, and partially inhibited with phosphate plus either ATP or Mg2+. Between 0 and 7 μM added Ca2+ and in the presence of phosphate, ATP and Mg2+, tri-Calciphor stimulated the uptake of Ca2+ by mitochondria and increased the efficiency of buffering of extramitochondrial Ca2+. Thus depending on the assay conditions, two different effects involving Ca2+ movements and mitochondria are observed with tri-Calciphor. 相似文献
14.
H. Keith Massel Salvador Macias Darlene M. Meador Duane M. Rumbaugh 《International journal of primatology》1981,2(1):9-17
Twenty-month-old rhesus monkeys were tested in a modified discrimination-reversal paradigm, which was designed to distinguish
abstract learning from stimulus-response associational learning. Previous studies indicate that talapoin monkeys learn associationally
and great apes via forming abstract concepts. Adult rhesus monkeys are apparently capable of forming simple abstractions,
but learn primarily through associational process. The results of this study show the adolescent rhesus monkeys to be associational
learners, with their response patterns indicating more complexity than the talapoins but less than the adult rhesus monkeys.
The data suggest that rhesus monkeys develop their low-level capacity of abstract learning with maturation. 相似文献
15.
Lipopolysaccharide (LPS) induced a time-dependent synthesis of nitric oxide (NO) in EMT6 adenocarcinoma cells, assayed by accumulation of NO-derived nitrite in the medium. The induction NO synthesis was inhibited in a concentration-dependent manner by the glucocorticoids dexamethasone (IC50 = 5 nM) and hydrocortisone (IC50 = 20 nM) and this effect was partially antagonized by progesterone and cortexolone. If addition of dexamethasone was delayed 6 h or more, inhibition of nitrite accumulation over 24 h was substantially reduced, indicating a lack of direct effect of glucocorticoids on the NO synthase. Nitrite accumulation was accompanied by cell damage, which was increased by L-arginine and inhibited by (L-NMMA) and dexamethasone. These data show that NO is a primary cytotoxic mediator and that suppression of its formation by glucocorticoids explains some of their anti-inflammatory and cytoprotective effects. 相似文献
16.
Gilberto N. Salvador Calebe Maia Guilherme M. Dutra Tiago C. Pessali Naraiana L. Benone Luciano F. A. Montag Tiago M. S. Freitas 《Zeitschrift fur angewandte Ichthyologie》2019,35(4):1039-1041
The present study provides the length–weight relationships (LWR) for eight fish species in 19 streams from the Pedreira River basin, a small tributary of the Guyana coastal drainages from Amapá State, Brazil. Fishes were collected at two occasions, one in November 2016, the other in July 2018, using hand nets, with 0.5 mm of mesh size and 0.25 m2 of mouth area, and trawl nets, with 0.5 mm of mesh size and 3 m long. Standard length and total weight were measured to determine the LWRs. The results show that the coefficient b varied between 2.798 and 3.380 and thus the values were within the expected range. 相似文献
17.
Nicola Gasparini Michael Salvador Sebastian Strohm Thomas Heumueller Ievgen Levchuk Andrew Wadsworth James H. Bannock John C. de Mello Hans‐Joachim Egelhaaf Derya Baran Iain McCulloch Christoph J. Brabec 《Liver Transplantation》2017,7(19)
Organic solar cells that are free of burn‐in, the commonly observed rapid performance loss under light, are presented. The solar cells are based on poly(3‐hexylthiophene) (P3HT) with varying molecular weights and a nonfullerene acceptor (rhodanine‐benzothiadiazole‐coupled indacenodithiophene, IDTBR) and are fabricated in air. P3HT:IDTBR solar cells light‐soaked over the course of 2000 h lose about 5% of power conversion efficiency (PCE), in stark contrast to [6,6]‐Phenyl C61 butyric acid methyl ester (PCBM)‐based solar cells whose PCE shows a burn‐in that extends over several hundreds of hours and levels off at a loss of ≈34%. Replacing PCBM with IDTBR prevents short‐circuit current losses due to fullerene dimerization and inhibits disorder‐induced open‐circuit voltage losses, indicating a very robust device operation that is insensitive to defect states. Small losses in fill factor over time are proposed to originate from polymer or interface defects. Finally, the combination of enhanced efficiency and stability in P3HT:IDTBR increases the lifetime energy yield by more than a factor of 10 when compared with the same type of devices using a fullerene‐based acceptor instead. 相似文献
18.
Nitric oxide, cell bioenergetics and neurodegeneration 总被引:18,自引:0,他引:18
19.
George B. McManus Barbara A. Costas Hans G. Dam Rubens M. Lopes Salvador A. Gaeta Sylvia M. Susini Carol H. Rosetta 《Hydrobiologia》2007,575(1):69-81
We measured grazing by herbivorous zooplankton (<200 μm fraction) in coastal and slope regions of the South Brazil Bight.
Using the dilution technique, we performed nine experiments during the austral summer, when nutrient-rich South Atlantic Central
Water is present on the shelf, and five during winter. These experiments provide the first estimates of microzooplankton grazing
in the western South Atlantic Ocean. Model II regression showed a strong relationship between phytoplankton intrinsic growth
rates and grazing, with a slope of 0.64 (±0.28; 95% confidence interval) indicating that microzooplankton grazing could account
for the majority of phytoplankton mortality. Both phytoplankton growth and microzooplankton grazing were higher during the
summer upwelling season, compared to winter. For the two experiments that were conducted in oligotrophic slope water, grazing
accounted for >80% of phytoplankton production. A comparison of incubations with and without added inorganic nutrients showed
no consistent stimulation of phytoplankton growth (slope of enriched versus unenriched treatments not significantly different
from 1). Estimates from microscopic counts of heterotrophic organisms >10 μm indicated that copepod nauplii comprised the
largest share of the microzooplankton biomass (mean 62.4 ± 5.8% SE). Grazing estimates were not correlated with microzooplankton
biomass, whether or not nauplii were included, suggesting that most of the grazing was done by nano-sized zooplankton.
Electronic Supplementary Material Electronic supplementary material is available in the online version of this article at and is accessible for authorized users.
Handling editor: S. Wellekens 相似文献
20.
Jordi Mayneris-Perxachs María Arnoriaga-Rodríguez Josep Garre-Olmo Josep Puig Rafael Ramos Maria Trelis Aurelijus Burokas Cludia Coll Cristina Zapata-Tona Salvador Pedraza Vicente Prez-Brocal Lluís Rami Wifredo Ricart Andrs Moya Mariona Jov Joaquim Sol Manuel Portero-Otin Reinald Pamplona Rafael Maldonado Jos Manuel Fernndez-Real 《The ISME journal》2022,16(9):2181
Growing evidence implicates the gut microbiome in cognition. Blastocystis is a common gut single-cell eukaryote parasite frequently detected in humans but its potential involvement in human pathophysiology has been poorly characterized. Here we describe how the presence of Blastocystis in the gut microbiome was associated with deficits in executive function and altered gut bacterial composition in a discovery (n = 114) and replication cohorts (n = 942). We also found that Blastocystis was linked to bacterial functions related to aromatic amino acids metabolism and folate-mediated pyrimidine and one-carbon metabolism. Blastocystis-associated shifts in bacterial functionality translated into the circulating metabolome. Finally, we evaluated the effects of microbiota transplantation. Donor’s Blastocystis subtypes led to altered recipient’s mice cognitive function and prefrontal cortex gene expression. In summary, Blastocystis warrant further consideration as a novel actor in the gut microbiome-brain axis.Subject terms: Biomarkers, Pathogenesis, Diagnosis 相似文献