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991.
Cássio S. Meira José Maurício dos Santos Filho Caroline C. Sousa Pâmela S. Anjos Jéssica V. Cerqueira Humberto A. Dias Neto Rafael G. da Silveira Helena M. Russo Jean-Luc Wolfender Emerson F. Queiroz Diogo R.M. Moreira Milena B.P. Soares 《Bioorganic & medicinal chemistry》2018,26(8):1971-1985
4-(Nitrophenyl)hydrazone derivatives of N-acylhydrazone were synthesized and screened for suppress lymphocyte proliferation and nitrite inhibition in macrophages. Compared to an unsubstituted N-acylhydrazone, active compounds were identified within initial series when hydroxyl, chloride and nitro substituents were employed. Structure-activity relationship was further developed by varying the position of these substituents as well as attaching structurally-related substituents. Changing substituent position revealed a more promising compound series of anti-inflammatory agents. In contrast, an N-methyl group appended to the 4-(nitrophenyl)hydrazone moiety reduced activity. Anti-inflammatory activity of compounds is achieved by modulating IL-1β secretion and prostaglandin E2 synthesis in macrophages and by inhibiting calcineurin phosphatase activity in lymphocytes. Compound SintMed65 was advanced into an acute model of peritonitis in mice, where it inhibited the neutrophil infiltration after being orally administered. In summary, we demonstrated in great details the structural requirements and the underlying mechanism for anti-inflammatory activity of a new family of hydrazone-N-acylhydrazone, which may represent a valuable medicinal chemistry direction for the anti-inflammatory drug development in general. 相似文献
992.
Paulo E. da Costa Wagner L. Batista Miriam S. Moraes Arnold Stern 《Free radical research》2018,52(5):592-604
Tumour progression involves the establishment of tumour metastases at distant sites. Resistance to anoikis, a form of cell death that occurs when cells lose contact with the extracellular matrix and with neighbouring cells, is essential for metastases. NO has been associated with anoikis. NO treated HeLa cells and murine melanoma cells in suspension triggered a nitric oxide (NO)-Src kinase signalling circuitry that enabled resistance to anoikis. Two NO donors, sodium nitroprusside (SNP) (500 µM) and DETANO (125 µM), protected against cell death derived from detachment of a growth permissive surface (experimental anoikis). Under conditions of NO-mediated Src activation the following were observed: (a) down-regulation of the pro-apoptotic proteins Bim and cleaved caspase-3 and the cell surface protein, E-cadherin, (b) up-regulation of caveolin-1, and (c) the dissociation of cell aggregates formed when cells are detached from a growth permissive surface. Efficiency of reattachment of tumour cells in suspension and treated with different concentrations of an NO donor, was dependent on the NO concentration. These findings indicate that NO-activated Src kinase triggers a signalling circuitry that provides resistance to anoikis, and allows for metastases. 相似文献
993.
Hélio Nitta Matsuura Sonia Malik Fernanda de Costa Morteza Yousefzadi Mohammad Hossein Mirjalili Randolph Arroo Avninder S. Bhambra Miroslav Strnad Mercedes Bonfill Arthur Germano Fett-Neto 《Molecular biotechnology》2018,60(2):169-183
Plant secondary metabolism evolved in the context of highly organized and differentiated cells and tissues, featuring massive chemical complexity operating under tight environmental, developmental and genetic control. Biotechnological demand for natural products has been continuously increasing because of their significant value and new applications, mainly as pharmaceuticals. Aseptic production systems of plant secondary metabolites have improved considerably, constituting an attractive tool for increased, stable and large-scale supply of valuable molecules. Surprisingly, to date, only a few examples including taxol, shikonin, berberine and artemisinin have emerged as success cases of commercial production using this strategy. The present review focuses on the main characteristics of plant specialized metabolism and their implications for current strategies used to produce secondary compounds in axenic cultivation systems. The search for consonance between plant secondary metabolism unique features and various in vitro culture systems, including cell, tissue, organ, and engineered cultures, as well as heterologous expression in microbial platforms, is discussed. Data to date strongly suggest that attaining full potential of these biotechnology production strategies requires being able to take advantage of plant specialized metabolism singularities for improved target molecule yields and for bypassing inherent difficulties in its rational manipulation. 相似文献
994.
Eric van de Weg Mario Di Guardo Melanie Jänsch Didier Socquet-Juglard Fabrizio Costa Isabelle Baumgartner Giovanni A. L. Broggini Markus Kellerhals Michela Troggio François Laurens Charles-Eric Durel Andrea Patocchi 《Molecular breeding : new strategies in plant improvement》2018,38(1):5
Most cultivated apple cultivars are highly susceptible to fire blight, caused by Erwinia amylovora. However, differences in resistance levels are observed among cultivars and could be used in breeding. In this paper, we investigated the genetic basis of fire blight resistance of the cultivar ‘Enterprise’ and the advanced breeding selection X-6398. Genotyped pedigrees were used for validating and curating historic pedigree records. Various quantitative trait locus (QTL) discovery approaches were applied on the full-sib families ‘Gala’ × ‘Enterprise’ (GaEn) and X-6398 × X-6683 (IW) with the software FlexQTL? and MapQTL®. The paternal lineage of ‘Enterprise’ was reconstructed and showed to include ‘Cox’s Orange Pippin’. The QTLs found varied with the software used. Using FlexQTL?, two were found on linkage groups (LGs) 7 and 13, favourable alleles inherited by Enterprise from ‘Cox’s Orange Pippin’ and ‘Golden Delicious’, respectively. The former was identical to the previously named FB_F7 allele from ‘Fiesta’, while the latter is new and has been named FB_13GD. X-6398 had a QTL at the same position as FB_F7. Its favourable allele was new, originating from the unknown grandfather of X-4598, and was named FB_7X-6398. Using MapQTL® on GaEn, FB_F7 was also identified. Performing the same analysis on the subset of offspring that carried the favourable allele of FB_F7, two putative QTLs on LG8 and on top of LG13 were identified, which showed interactions with FB_F7. Implication of the findings for breeding for fire blight-resistant apples is discussed. Single nucleotide polymorphism data on Enterprise and its ancestors are provided. 相似文献
995.
G. Gaglio P. Battaglia A. Costa M. Cavallaro G. Cammilleri S. Graci M.D. Buscemi V. Ferrantelli F. Andaloro F. Marino 《Parasitology international》2018,67(1):23-28
In this work 437 fish samples of species belonging to the families Myctophidae (Electrona risso and Diaphus metopoclampus) and Phosichthyidae (Vinciguerria attenuata) were examined for the presence of Anisakidae larvae. The study was performed with fishes in the central Mediterranean Sea, particularly in the Strait of Sicily and in the Strait of Messina. The visual inspection and chloro-peptic analysis revealed the presence of nematode parasites with prevalence values between 2.9% in Electrona risso samples and 5.4% in Vinciguerria attenuata samples. A positive correlation was found between standard length (SL) and prevalence of infestation in D. metopoclampus samples (p < 0.05). The larvae examined were morphologically ascribed, at genus level, to Anisakis morphotypes I and II and molecularly identified as Anisakis pegreffii, Anisakis ziphidarum and Anisakis physeteris, in 67%, 9% and 24% of the fish samples examined. Overall, A. pegreffii and A. ziphidarum larvae were isolated in 14 and 2 specimens of D. metopoclampus respectively, A. physeteris larvae were found in 3 E. risso and 2 V. attenuata. A positive correlation was found between standard length and prevalence of infestation in D. metopoclampus samples (p < 0.05). First information is provided on the presence of Anisakis spp. larvae of the myctophid fish species E. risso, D. metopoclampus and V. attenuata from the Central Mediterranean. It is also confirmed the role of lanternfishes (Myctophidae) as paratenic hosts for Anisakis spp. 相似文献
996.
Influence of the margin vegetation on the conservation of aphid biological control in apple orchards
Luan Alberto Odorizzi Santos Marlice Botelho Costa Claire Lavigne Odair Aparecido Fernandes Armin Bischoff Pierre Franck 《Journal of Insect Conservation》2018,22(3-4):465-474
The influence of three margin strip treatments (wildflower strips, grass strips and spontaneous vegetation) adjacent to apple orchards on the biological control of Dysaphis plantaginea Passerini (Hemiptera: Aphididae) was compared during two consecutive years. The wildflower strips provided the highest amount of floral resources. Within the margin strips, hoverflies responded positively to higher resource provisioning whereas ladybird abundance did not differ between strip treatments. Within the orchards, the presence of parasitoids, hoverflies, and ladybirds in aphid colonies and the predation of sentinel aphids were not significantly affected by the adjacent strip treatments. The number of natural enemies observed in aphid colonies was mainly driven by aphid number. Aphid numbers were higher close to the margin strips suggesting that aphid colonization from orchard edges may counteract the positive effect of wildflower strips on natural enemy abundance and on a reduction of aphid infestation. The results confirm the positive influence of floral resource provisioning by wildflower strips on the conservation of aphid natural enemies, but also suggest that effects of wildflower strips on aphid regulation inside orchards are not very strong compared with spontaneous vegetation naturally occurring in the margins. 相似文献
997.
R. A. Costa R. S. T. Martins E. Capilla L. Anjos D. M. Power 《BMC evolutionary biology》2018,18(1):191
Background
Osteoglycin (OGN, a.k.a. mimecan) belongs to cluster III of the small leucine-rich proteoglycans (SLRP) of the extracellular matrix (ECM). In vertebrates OGN is a characteristic ECM protein of bone. In the present study we explore the evolution of SLRP III and OGN in teleosts that have a skeleton adapted to an aquatic environment.Results
The SLRP gene family has been conserved since the separation of chondrichthyes and osteichthyes. Few gene duplicates of the SLRP III family exist even in the teleosts that experienced a specific whole genome duplication. One exception is ogn for which duplicate copies were identified in fish genomes. The ogn promoter sequence and in vitro mesenchymal stem cell (MSC) cultures suggest the duplicate ogn genes acquired divergent functions. In gilthead sea bream (Sparus aurata) ogn1 was up-regulated during osteoblast and myocyte differentiation in vitro, while ogn2 was severely down-regulated during bone-derived MSCs differentiation into adipocytes in vitro.Conclusions
Overall, the phylogenetic analysis indicates that the SLRP III family in vertebrates has been under conservative evolutionary pressure. The retention of the ogn gene duplicates in teleosts was linked with the acquisition of different functions. The acquisition by OGN of functions other than that of a bone ECM protein occurred early in the vertebrate lineage.998.
999.
1000.
Noemi Carla Baron Nágila Torrini Alves Costa Dinalva Alves Mochi Everlon Cid Rigobelo 《Annals of microbiology》2018,68(12):863-870
Maize is one of the most important crops worldwide. It provides food for humans and animals and is used in biotechnological and industrial processes to produce a wide variety of products. The phosphorus (P) requirement for its development and production is high, but the absorption efficiency of this nutrient is insufficient to meet its requirements. The use of P-solubilizing fungi can increase this efficiency, thus reducing the amount of fertilizers applied to the crops. Therefore, this study aimed to verify the potential use of A. sydowii and A. brasiliensis and their effect in the field as bioinoculants when associated with three P fertilization doses. The experiment was carried out in a maize field, and treatments were presence and absence of fungi associated with P mineral fertilization doses. The parameters evaluated were shoot dry matter, P content in the plant, and P content in the soil. A. sydowii caused the highest P content in the plant and soil at fertilization doses of 75% and 100%, contradicting the expected results from in vitro assays that indicated that A. brasiliensis would provide better rates of P uptake. There was no difference in the other fertilization doses or for dry matter when comparing all treatments. This result strongly suggests that the use of A. sydowii can improve the efficiency of P absorption with fertilization application. In addition, the molecular analysis of the two fungi performed in this study contributes novel information on the use of both species during the agricultural process. 相似文献