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991.
Ana O. Fagundes Maira R. Aguiar Claudia S. Aguiar Giselli Scaini Monique U. Sachet Nayara M. Bernhardt Gislaine T. Rezin Samira S. Valvassori João Quevedo Emilio L. Streck 《Neurochemical research》2010,35(11):1675-1680
Methylphenidate is commonly used for the treatment of attention deficit/hyperactivity disorder. There are still few works
regarding the effects of methylphenidate on brain energy metabolism. Thus, in the present study we evaluated the effect of
chronic administration of methylphenidate on the activities of mitochondrial respiratory chain complexes I and III in the
brain of young rats. The effect of acute administration of methylphenidate on mitochondrial respiratory chain complexes I,
II, III and IV in the brain of young rats was also investigated. For acute administration, a single injection of methylphenidate
was given to rats on postnatal day 25. For chronic administration, methylphenidate injections were given starting at postnatal
day 25 once daily for 28 days. Our results showed that complexes I and III were not affected by chronic administration of
methylphenidate. Moreover, the acute administration of methylphenidate decreased complex I activity in cerebellum and prefrontal
cortex, whereas complexes II, III and IV were not altered. 相似文献
992.
Traditional cultivation-based methods to quantify microbial abundance are not suitable for analyses of microbial communities
in environmental or medical samples, which consist mainly of uncultured microorganisms. Recently, different cultivation-independent
quantification approaches have been developed to overcome this problem. Some of these techniques use specific fluorescence
markers, for example ribosomal ribonucleic acid targeted oligonucleotide probes, to label the respective target organisms.
Subsequently, the detected cells are visualized by fluorescence microscopy and are quantified by direct visual cell counting
or by digital image analysis. This article provides an overview of these methods and some of their applications with emphasis
on (semi-)automated image analysis solutions. 相似文献
993.
Dwarf bamboo species are monocarpic. They flower simultaneously and die after several decades. The type of flowering in the
genus Sasa ranges from sporadic to gregarious. In order to determine whether or not the sporadic flowering of dwarf bamboo is fixed
genetically, we investigated the distribution of clones using eight microsatellite (SSR) loci in a sporadic flowering patch
of Sasa cernua Makino, a major dwarf bamboo species found in central Hokkaido. In May 2006, flowering occurred on 60.5% of living culms
in a 1600 m2 patch. We established a 50 × 10 m study plot in this patch and noted 1267 clumps consisting of 2529 living culms. We investigated
all 1267 clumps and identified six multilocus genotypes as clones using five variable SSR loci. All flowering clumps belonged
to the same clone. On the other hand, non-flowering vegetative clumps were also discovered to be of the same clone. These
data suggest that all flowering culms originated from a single clone of a sporadic flowering patch of S. cernua. Clonal analysis for investigation of sporadic flowering of S. cernua revealed that only a portion of a clone flowers and dies instead of the whole clone. 相似文献
994.
Jurate Savickiene Grazina Treigyte Ceslava Aleksandraviciene Ruta Navakauskiene 《Central European Journal of Biology》2010,5(5):600-612
The biological effects of low-dose radiation have attracted attention, but data are currently insufficient to fully understand
the beneficial role of the phenomenon. In the present study, we have investigated the effects of low doses of gamma-irradiation
alone and in combination with all-trans-retinoic acid (RA) on proliferation, apoptosis and differentiation of the human promyelocytic leukemia HL-60 cells. Changes
in cell behavior and protein expression were determined with the use of light and fluorescent microscopy, immunocytochemical
and Western blot analysis. Low-dose irradiation with 1–100 cGy caused a dose-dependent inhibition of HL-60 cell proliferation,
and induced apoptosis and differentiation to granulocytes with an increase in the number of CD15-positive cells. Pre-irradiation
with 1–100 cGy for 24 h before treatment with RA promoted apoptosis but did not impair RA-induced differentiation. Both processes
were associated with a decrease in the expression of the proliferating cell nuclear antigen (PCNA), BCL-2, c-MYC, and changes
in both cytosolic and nuclear levels of protein tyrosine-phosphorylation as well as protein kinase C alpha or beta isoforms.
These results demonstrate the beneficial role of low-dose irradiation in modulating leukemia cell proliferation, differentiation
and apoptosis. 相似文献
995.
Laura Martins Fonseca Angélica Karine Henkes Graziella Pinheiro Bruni Lorena Aparecida Nunes Viana Catarina Motta de Moura Wladimir Hernandez Flores Alexandre Ferreira Galio 《Food biophysics》2018,13(2):163-174
The need to replace conventional polymers due to environmental pollution caused by them has led to increased production of biodegradable polymers such as starch. Thus, the application possibilities of starch have increased. In this study, we produced and characterized biodegradable films derived from native and oxidized potato starch. The film-forming solution was prepared with different concentrations of extracted starch (native or oxidized) and a plasticizer (glycerol or sorbitol). Then, the mechanical, barrier, morphological, and structural properties of the films were characterized. The moisture content of the films varied from 15.35?±?1.31 to 21.78?±?0.49%. The elastic modulus of the films ranged from 219?±?14.97 to 2299?±?62.91 MPa. The film of oxidized starch plasticized with sorbitol in the lowest content was the most resistant and flexible; moreover, this film also presented lower water vapor permeability and low solubility in water. Fourier-transform infrared spectroscopic analysis of the biodegradable films indicated the presence of same functional groups as those of starch with bands in the same regions. The film thickness was lower for the films plasticized with glycerol whereas the color variation (Δ?) was lower for the ones plasticized with sorbitol. In case of both plasticizers, the increase in their content decreased the Δ? value. All the biodegradable films presented stability against water absorption owing to their low solubility in water. Morphological evaluation revealed the presence of partially gelatinized starch granules in the films. The roughness parameter (Rq) of the films varied from 3.39 to 10.9 nm, indicating that their surfaces are smooth. X-ray diffraction studies showed a B-type pattern for the starches, which is representative of tubers. Further, the films present higher relative crystallinity (RC) compared to the starches. The biodegradable starch films are uniform, transparent and with low solubility in water. The oxidation of starch and use of sorbitol as a plasticizer resulted in improved properties of the starch films, which is suitable for application. 相似文献
996.
997.
998.
Depth of edge influence of the agricultural-forest landscape boundary,Southwestern China 总被引:2,自引:0,他引:2
The landscape boundary is an important component of a landscape and often plays an indispensable role in regulating ecological
flows. The primary objective of this study was to estimate how far the edge effects on agricultural-forest landscape boundaries
can penetrate into the forest and agricultural field. This will serve as a basis for understanding the interaction between
forest and agricultural fields in the mountainous area of southwestern China and provide scientific basis for the practice
of the policy of “returning agricultural field to forest.” Based on field investigations, three types of boundaries with six
sampling transects were selected. We investigated the soil moisture, soil nutrients and vegetation diversity along the transect
gradient and explored the depth of edge influence (DEI) with moving split-window techniques for analyzing the data. DEI for
soil moisture changed with the seasons, ranging from 6 m in the pepper field to 2 m in the forest during the dry season, and
from 12 m in the pepper field to 2 m in the forest after heavy rain. DEI based on soil organic matter ranged from 1.5 to 10 m
in the forest field, while it was not detected based on other soil nutrient factors. DEI based on vegetation diversity varied
from 4 to 26 m and from 10 to 31 m in the forest and agricultural fields, respectively. These results provide the scientific
basis for the policy “returning agricultural field to forest”. Based on these field observations, reducing human disturbance
and revegetating with natural shrubs and meadows could be more effective for vegetation conservation in terms of soil moisture
and soil nutrient content in the arid valley of the Minjiang River. 相似文献
999.
Fang-fang Zhuan Zhen-feng Zhang Di-ping Xu Yan-hong Si Han-Zhong Wang Ghopur Mijit 《中国病毒学》2007,22(4):316-325
lacZa-mini-attTn7 was inserted into the intergenic region between the gG and gD genes in a PRV bacterial artificial chromosome (BAC) by homologous
recombination in E. coli. The resulting recombinant BAC (pBeckerZF1) was confirmed by PCR and sequencing. Green fluorescent protein (GFP) gene was
then transposed into pBeckerZF1 by transposon Tn7 to generate pBeckerZF2. Recombinant viruses vBeckerZF1 and vBeckerZF2 were
generated by transfection with the corresponding BAC pBeckerZF1 or pBeckerZF2. The titers and cytopathic effect (CPE) observed
for by vBeckerZF1 and vBeckerZF2 was comparable to that of the parental virus vBecker3. vBeckerZF2 was serial passaged for
five rounds in cell culture, and the mini-Tn7 insertion was stably maintained in viral genome. These results show that recombinant
viruses can be rapidly and reliably created by Tn7-mediated transposition. This technology should accelerate greatly the pace
at which recombinant PRV can be generated and, thus, facilitate the use of recombinant viruses for detailed mutagenic studies.
Foundation item: Key technologies R&D program (2006BAD06A01) from the Ministry of Science and Technology of China. 相似文献
1000.
A study was performed to validate 3 FMDV 3ABC-I-ELISA kits developed in China for the differentiation of FMDV infected and vaccinated animals. Sets of sera from naive and vaccinated cattle as well as from cattle that had been infected were tested for antibodies against nonstructural proteins (NSPs) of FMDV by commercial diagnosis kits, Ceditest® FMDV-NS (Ceditest® kit), UBI® FMDV NONSTRUCTURAL PROTEIN ELISA DIRECTION INSERT (UBI® kit) and a FMDV 3ABC-I-ELISA kit developed at the Lanzhou Veterinary Research Institute. The test parameters (sensitivity and specificity) of the three kits were determined, and the result obtained from FMD 3ABC-I-ELISA kit was compared with that obtained from two foreign kits. The results indicated that the coincidence rate between the FMDV 3ABC-I-ELISA and Ceditest® kits was 98.05%, and the coincidence rate between the FMDV 3ABC-I-ELISA and UBI® kits was 94.4%; the sensitivity of both Ceditest® and FMDV 3ABC-I-ELISA kit was 100%. However, the sensitivity of the UBI® kit was only 81.8%. With sera from naive or vaccinated non-infected animals, the specificity of all tests exceeded 90%. 相似文献