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41.
Alves Leticia Rodrigues Rossatto Davi Rodrigo Rossi Mônica Lanzoni Martinelli Adriana Pinheiro Gratão Priscila Lupino 《Protoplasma》2020,257(2):597-605
Protoplasma - The application of Se to plants growing under Cd contamination may become an alternative strategy to minimize Cd damage. However, there is no specific information available regarding... 相似文献
42.
The MAPK pathway triggers activation of Nek2 during chromosome condensation in mouse spermatocytes 总被引:4,自引:0,他引:4
Chromosome condensation during the G2/M progression of mouse pachytene spermatocytes induced by the phosphatase inhibitor okadaic acid (OA) requires the activation of the MAPK Erk1. In many cell systems, p90Rsks are the main effectors of Erk1/2 function. We have identified p90Rsk2 as the isoform that is specifically expressed in mouse spermatocytes and have shown that it is activated during the OA-triggered meiotic G2/M progression. By using the MEK inhibitor U0126, we have demonstrated that activation of p90Rsk2 during meiotic progression requires activation of the MAPK pathway. Immunofluorescence analysis indicates that activated Erks and p90Rsk2 are tightly associated with condensed chromosomes during the G2/M transition in meiotic cells. We also found that active p90Rsk2 was able to phosphorylate histone H3 at Ser10 in vitro, but that the activation of the Erk1/p90Rsk2 pathway was not necessary for phosphorylation of H3 in vivo. Furthermore, phosphorylation of H3 was not sufficient to cause condensation of meiotic chromosomes in mouse spermatocytes. Other proteins known to associate with chromatin may represent effectors of Erk1 and p90Rsk2 during chromosome condensation. Nek2 (NIMA-related kinase 2), which associates with chromosomes, plays an active role in chromatin condensation and is stimulated by treatment of pachytene spermatocytes with okadaic acid. We show that inhibition of the MAPK pathway by preincubation of spermatocytes with U0126 suppresses Nek2 activation, and that incubation of spermatocyte cell extracts with activated p90Rsk2 causes stimulation of Nek2 kinase activity. Furthermore, we show that the Nek2 kinase domain is a substrate for p90Rsk2 phosphorylation in vitro. These data establish a connection between the Erk1/p90Rsk2 pathway, Nek2 activation and chromosome condensation during the G2/M transition of the first meiotic prophase. 相似文献
43.
Manco G Carrea G Giosuè E Ottolina G Adamo G Rossi M 《Extremophiles : life under extreme conditions》2002,6(4):325-331
The esterase genes est2 from Alicyclobacillus acidocaldarius and AF1716 from Archaeoglobus fulgidus were subjected to error-prone PCR in an effort to increase the low enantioselectivity of the corresponding enzymes EST2 and AFEST, respectively. The model substrate ( RS)- p-nitrophenyl-2-chloropropionate was chosen to produce ( S)-2-chloropropionic acid, an important intermediate in the synthesis of some optically pure compounds, such as the herbicide mecoprop. In the case of EST2, a single mutant, Leu212Pro, was obtained showing a slightly enhanced preference toward the ( S) substrate; in the case of AFEST, a double mutant, Leu101Ile/Asp117Gly, was obtained showing an increased preference in the opposite direction. The 3-D structures of the EST2 and AFEST enzymes were analyzed by molecular modeling to determine the effects of the mutations. Mutations were positioned differently in the structures, but in both cases caused small modifications around the active site and in the oxyanion loop. 相似文献
44.
45.
Fleur E van de Geijn Manfred Wuhrer Maurice HJ Selman Sten P Willemsen Ya?l A de Man André M Deelder Johanna MW Hazes Radboud JEM Dolhain 《Arthritis research & therapy》2009,11(6):R193
Introduction
Improvement of rheumatoid arthritis (RA) during pregnancy has been causatively associated with increased galactosylation of immunoglobulin G (IgG) N-glycans. Since previous studies were small, did not include the postpartum flare and did not study sialylation, these issues were addressed in the present study. 相似文献46.
Szerman N Schroh I Rossi AL Rosso AM Krymkiewicz N Ferrarotti SA 《Bioresource technology》2007,98(15):2886-2891
Cyclodextrins (CD) are cyclic oligosaccharides with multiple applications in the food, pharmaceutical, cosmetic, agricultural and chemical industries. In this work, the conditions used to produce CD with cyclodextrin glycosyltransferase from Bacillus circulans DF 9R were optimized using experimental designs. The developed method allowed the partial purification and concentration of the enzyme from the cultural broth and, subsequently, the CD production, using the same cassava starch as enzyme adsorbent and as substrate. Heat-treatment of raw starch at 70 degrees C for 15 min in the presence of adsorbed cyclodextrin glycosyltransferase allowed the starch liquefaction without enzyme inactivation. The optimum conditions for CD production were: 5% (w/v) cassava starch, 15 U of enzyme per gram of substrate, reaction temperature of 56 degrees C and pH 6.4. After 4h, the proportion of starch converted to CD reached 66% (w/w) and the weight ratio of alpha-CD:beta-CD:gamma-CD was 1.00:0.70:0.16. 相似文献
47.
The role of adult faeces in juvenile nutrition of two isopod species, Proasellus coxalis s.l. and Asellus aquaticus (L.),
with similar trophic strategies and different reproductive output, has been studied in laboratory. Our aim was to consider
the possible competitive mechanisms occurring at the beginning of the species coexistence using allopatric populations in
single and mixed species experiments. Two series of competition experiments were performed. In the first, adult specimens
were used for breeding and feeding trials. Both population dynamics and the percentage of ovigerous females and juveniles
were evaluated during 10 months. Adult densities and juvenile percentage of A.aquaticus were lower in the presence of P. coxalis
s.l. than when alone. At the end of the breeding experiments the dietary preferences of adults on a set of fungally conditioned
leaf discs were not different among treatments. In the second series of experiments, the influence of coexistence on the feeding
rates of young asellids and the relative importance of faeces and decaying plant material in their diet were investigated.
Individual consumption by wild juveniles in multiple-choice laboratory experiments was measured by radioisotopes (32
2P). Juveniles of P. coxalis s.l. showed the highest ingestion rates. In co-occurrence, contrary to A.aquaticus, they were
able to further increase feeding on parental faeces. The role of parental faeces in the diet of the two species juveniles
and the competitive dominance of P. coxalis s.l. are discussed.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
48.
Carlotta Giromini Raffaella Rebucci Eleonora Fusi Luciana Rossi Francesca Saccone Antonella Baldi 《Cell biology and toxicology》2016,32(3):249-258
This study aimed to investigate the in vitro damage induced by ochratoxin A (OTA) in BME-UV1 and MDCK epithelial cells. Both cells lines were treated with OTA (0 up to 10 μg/mL), and cell viability (MTT assay), membrane stability (lactate dehydrogenase (LDH) release assay) and apoptotic cell rate (Tunel assay) were investigated. Further, the effect of the incubation with OTA has been evaluated at DNA level by the determination of DNA integrity, by the quantification of DNA adduct formation (8-hydroxy-2′-deoxyguanosine (8-OHdG)) and by the assessment of the global DNA methylation status (5-methyl-cytosine (5-mC)). The obtained results showed that after 24 h of OTA treatment, BME-UV1 cell viability was reduced in a dose-dependent way. OTA significantly (P?<?0.05) increased LDH release in BME-UV1 cells at all concentrations tested. OTA (1.25 μg/mL) induced 35 % LDH release in MDCK cells (P?<?0.05). A significant (P?<?0.05) change in percentages of apoptotic BME-UV1 (10?±?0.86) and MDCK (25?±?0.88) cells was calculated when the cells were co-incubated with OTA. The level of 8-OHdG adduct formation was significantly (P?<?0.05) increased in BME-UV1 cells treated with 1.25 μg/mL of OTA. The results of the present study suggest that a different mechanism of action may occur in these cell lines. 相似文献
49.
Large and dissimilar repertoire of Melan-A/MART-1-specific CTL in metastatic lesions and blood of a melanoma patient 总被引:4,自引:0,他引:4
Mandruzzato S Rossi E Bernardi F Tosello V Macino B Basso G Chiarion-Sileni V Rossi CR Montesco C Zanovello P 《Journal of immunology (Baltimore, Md. : 1950)》2002,169(7):4017-4024
It is widely accepted that the repertoire of Melan-A-specific T cells naturally selected in melanoma patients is diverse and mostly nonoverlapping among different individuals. To date, however, no studies have addressed the TCR profile in different tumor sites and the peripheral blood from the same patient. We compared the TCR usage of Melan-A-specific T cells from different compartments of a single melanoma patient to evaluate possible clonotype expansion or preferential homing over a 4-mo follow-up period. Using HLA-A2 peptide tetramers, CD8(+) T cells recognizing the modified Melan-A immunodominant ELAGIGILTV peptide were isolated from four metastatic lesions resected from a single melanoma patient, and their TCR repertoire was studied. A panel of T cell clones was generated by cell cloning of tetramer-positive cells. Analysis of the TCR beta-chain V segment and the complementarity-determining region 3 (CDR3) length and sequence revealed a large diversity in the TCR repertoire, with only some of the clones showing a partial conservation in the CDR3. A similar degree of diversity was found by analyzing a number of T cell clones obtained after sorting a Melan-A-specific population derived from PBLs of the same patient after in vitro culture with the immunodominant epitope. Moreover, clonotypes found at one site were not present in another, suggesting the lack of expansion and circulation of one or more clonotypes. Taken together, these results buttress the notion that the CTLs recognizing the immunodominant Ag of Melan-A comprise a high number of different clonotypic TCR, of which only some exhibit common features in the CDR3. 相似文献
50.
Differential toxicity of TAR DNA‐binding protein 43 isoforms depends on their submitochondrial localization in neuronal cells 下载免费PDF全文
Illari Salvatori Alberto Ferri Silvia Scaricamazza Ilaria Giovannelli Alessia Serrano Simona Rossi Nadia D'Ambrosi Mauro Cozzolino Andrea Di Giulio Sandra Moreno Cristiana Valle Maria Teresa Carrì 《Journal of neurochemistry》2018,146(5):585-597