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21.
The ability of the carcinogen, N-acetoxy-2-acetylaminofluorene (N-AcO-AAF), to induce mutations to azaguanine resistance in diploid human cells was quantitatively investigated and shown to be dose-dependent. The 8-azaguanine (AG) resistance was shown to be heritable in the absence of mutagen or selective agent and the cells of the mutant clones were shown to retain normal sensitivity to N-AcO-AAF. 相似文献
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Erukainure Ochuko L. Salau Veronica F. Atolani Olubunmi Ravichandran Rahul Banerjee Priyanka Preissner Robert Koorbanally Neil A. Islam Md. Shahidul 《Amino acids》2021,53(7):1135-1151
Amino Acids - The antidiabetic effect of l-leucine has been attributed to its modulatory effect on glucose uptake and lipid metabolism in muscles. However, there is a dearth on its effect on... 相似文献
24.
Anaya-Ramos Laura Díaz-Ruíz Araceli Ríos Camilo Mendez-Armenta Marisela Montes Sergio Aguirre-Vidal Yoshajandith García-Jiménez Sara Baron-Flores Veronica Monroy-Noyola Antonio 《Biometals》2021,34(6):1295-1311
BioMetals - Thallium (TI) is one of the most toxic heavy metals. Human exposure to Tl occurs through contaminated drinking water and from there to food, a threat to health. Recently, environmental... 相似文献
25.
Maglieri Veronica Riccobono Marco Germain Giunchi Dimitri Palagi Elisabetta 《Journal of Ethology》2021,39(3):287-296
Journal of Ethology - By gathering data on people during their ordinary daily activities, we tested if looking at, but not manipulating, smartphones led to a mimicry response in the observer.... 相似文献
26.
Fais Giacomo Malavasi Veronica Scano Paola Soru Santina Caboni Pierluigi Cao Giacomo 《Extremophiles : life under extreme conditions》2021,25(4):357-368
Extremophiles - With an unsupervised GC–MS metabolomics approach, polar metabolite changes of the microalgae Coccomyxa melkonianii SCCA 048 grown under standard conditions for seven weeks... 相似文献
27.
28.
During meal events, a child's food can be contaminated through contacts with objects and surfaces, and/or unwashed hands that have chemical residues, increasing ingestion exposure of contaminants for the child. This is not surprising, given that very young children eat more with the hands than adults, are active, and play with toys and objects while eating. In addition, children's unwashed hands and toys are commonly inserted into their mouths during meal events, increasing exposure. By observing children during their meal events, information can be gathered on the frequency and duration of contacts between objects, foods, and hands, and the sequence of events before the hands, foods, or objects are inserted into the mouth. This article describes the process of refining a videotaping and video-translation methodology to capture micro-level activity time series (MLATS), in order to better quantify total exposure for young children as a result of their behavior during meal events and cross-contamination of foods and hands. These MLATS can be seen as detailed activity patterns that provide useful data, along with transfer coefficients and environmental concentration to estimate exposures. 相似文献
29.
Živan Gojkovic Ines Garbayo-Nores Veronica Gómez-Jacinto Tamara García-Barrera José-Luis Gómez-Ariza Ivana Márová Carlos Vílchez-Lobato 《Process Biochemistry》2013,48(8):1235-1241
This article describes the enrichment of the fresh-water green microalga Chlorella sorokiniana in selenomethionine (SeMet). The microalga was cultivated in a 2.2 L glass-vessel photobioreactor, in a culture medium supplemented with selenate (SeO42?) concentrations ranging from 5 to 50 mg L?1. Although selenate exposure lowered culture viability, C. sorokiniana grew well at all tested selenate concentrations, however cultures supplemented with 50 mg L?1 selenate did not remain stable at steady state. A suitable selenate concentration in fresh culture medium for continuous operation was determined, which allowed stable long-term cultivation at steady state and maximal SeMet productivity. In order to do that, the effect of dilution rate on biomass productivity, viability and SeMet content of C. sorokiniana at several selenate concentrations were determined in the photobioreactor. A maximal SeMet productivity of 21 μg L?1 day?1 was obtained with 40 mg L?1 selenate in the culture medium. Then a continuous cultivation process at several dilution rates was performed at 40 mg L?1 selenate obtaining a maximum of 246 μg L?1 day?1 SeMet at a low dilution rate of 0.49 day?1, calculated on total daily effluent volume. This paper describes for the first time an efficient long-term continuous cultivation of C. sorokiniana for the production of biomass enriched in the high value amino acid SeMet, at laboratory scale. 相似文献
30.
Araceli Espinosa-Jeffrey Pablo M. Paez Veronica T. Cheli Vilma Spreuer Ina Wanner Jean de Vellis 《PloS one》2013,8(12)
We have recently established a culture system to study the impact of simulated microgravity on oligodendrocyte progenitor cells (OPCs) development. We subjected mouse and human OPCs to a short exposure of simulated microgravity produced by a 3D-Clinostat robot. Our results demonstrate that rodent and human OPCs display enhanced and sustained proliferation when exposed to simulated microgravity as assessed by several parameters, including a decrease in the cell cycle time. Additionally, OPC migration was examined in vitro using time-lapse imaging of cultured OPCs. Our results indicated that OPCs migrate to a greater extent after stimulated microgravity than in normal conditions, and this enhanced motility was associated with OPC morphological changes. The lack of normal gravity resulted in a significant increase in the migration speed of mouse and human OPCs and we found that the average leading process in migrating bipolar OPCs was significantly longer in microgravity treated cells than in controls, demonstrating that during OPC migration the lack of gravity promotes leading process extension, an essential step in the process of OPC migration. Finally, we tested the effect of simulated microgravity on OPC differentiation. Our data showed that the expression of mature oligodendrocyte markers was significantly delayed in microgravity treated OPCs. Under conditions where OPCs were allowed to progress in the lineage, simulated microgravity decreased the proportion of cells that expressed mature markers, such as CC1 and MBP, with a concomitant increased number of cells that retained immature oligodendrocyte markers such as Sox2 and NG2. Development of methodologies aimed at enhancing the number of OPCs and their ability to progress on the oligodendrocyte lineage is of great value for treatment of demyelinating disorders. To our knowledge, this is the first report on the gravitational modulation of oligodendrocyte intrinsic plasticity to increase their progenies. 相似文献