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991.
Wellington Ronildo Clarindo Carlos Roberto de Carvalho Fernanda Santos Araújo Isabella Santiago de Abreu Wagner Campos Otoni 《Plant Cell, Tissue and Organ Culture》2008,92(2):207-214
Several protocols have been proposed for in vitro propagation of papaya, either based on somatic embryogenesis or shoot organogenesis.
It is well-known that tissue culture-based approaches are frequently associated with somaclonal variation. Whether on the
one hand this phenomenon can preclude further stages of in vitro culture, on the other hand it can generate useful genetic
variability for crop improvement. However, somaclonal variation analyses are limited in papaya tissue culture. The DNA ploidy
level of 250 papaya somatic embryogenesis-derived plantlets from immature zygotic embryos was analyzed by flow cytometry.
In vitro-grown and greenhouse seed-derived plantlets were used as diploid standards. Flow cytometry unambiguously evidenced
euploid (diploid, mixoploid, triploid and tetraploid) and aneuploid papaya plantlets, indicating that in vitro culture conditions
can lead the occurrence of somaclonal variation. Additionally, the two subsequent flow cytometry analyses showed that the
DNA ploidy level remained stable in all cloned papaya plantlets during the successive subcultures in the multiplication medium. 相似文献
992.
Sandra Fernanda Bilbao Orozco Beatriz Vahan Kilikian 《World journal of microbiology & biotechnology》2008,24(2):263-268
The production of red pigments and citrinin by Monascus purpureus CCT3802 was investigated in submerged batch cultures performed in two phases: in the first phase, cells were grown on glucose,
at pH 4.5, 5.5 or 6.5; after glucose depletion, pH was adjusted, when necessary, to 4.5, 5.5, 6.5, 7.0, 8.0 or 8.5, for a
production phase. The highest total red pigments absorbance of 11.3 U was 16 times greater than the lowest absorbance and
was achieved with growth at pH 5.5, followed by production at pH 8.5, which causes an immediate reduction of the intra cellular
red pigments from 75% to 17% of the total absorbance. The lowest citrinin concentration, 5.5 mg L−1, was verified in the same culture while the highest concentration, 55 mg L−1, was verified in cultures entirely carried out at pH 5.5. An alkaline medium, besides promoting intra cellular red pigments
excretion, strongly represses citrinin synthesis. 相似文献
993.
Fernanda Emiko Izumida Eduardo Buozi Moffa Carlos Eduardo Vergani Ana Lúcia Machado Janaína Habib Jorge 《Biofouling》2014,30(5):525-533
This study evaluated the effect of experimental coatings, containing zwitterion or hydrophilic monomers, on the adherence of Candida albicans, Candida glabrata, and Streptococcus mutans to an acrylic resin. Acrylic samples (smooth or rough surfaces) were left untreated (control) or coated with one of the following experimental coatings: 3-hydroxypropylmethacrylate (HP) or sulfobetaine methacrylate (S), at concentrations of 25, 30, or 35%. Half of the specimens were coated with saliva. The adhesion test was performed by incubating specimens in C. albicans, C. glabrata, and S. mutans suspensions at 37°C for 90?min. The number of adhered microorganisms was determined by metabolic activity (XTT) and by cell viability (CFU). All coated specimens exhibited lower absorbance and CFU values compared to control specimens. Saliva and roughness did not promote microorganism adherence. An XPS analysis confirmed the modification in the chemical composition of the coatings in the experimental samples. These experimental coatings significantly reduced the adherence of C. albicans, C. glabrata and S. mutans to acrylic resin. 相似文献
994.
Fernanda M. Tahamtani Tone Beate Hansen Rachel Orritt Christine Nicol Randi O. Moe Andrew M. Janczak 《PloS one》2014,9(9)
This study tests the hypothesis that hens that are reared in aviaries but produce in furnished cages experience poorer welfare in production than hens reared in caged systems. This hypothesis is based on the suggestion that the spatial restriction associated with the transfer from aviaries to cages results in frustration or stress for the aviary reared birds. To assess the difference in welfare between aviary and cage reared hens in production, non-beak trimmed white leghorn birds from both rearing backgrounds were filmed at a commercial farm that used furnished cage housing. The videos were taken at 19 and 21 weeks of age, following the birds'' transition to the production environment at 16 weeks. Videos were analysed in terms of the performance of aversion-related behaviour in undisturbed birds, comfort behaviour in undisturbed birds, and alert behaviour directed to a novel object in the home cage. A decrease in the performance of the former behaviour and increase in the performance of the latter two behaviours indicates improved welfare. The results showed that aviary reared birds performed more alert behaviour near to the object than did cage reared birds at 19 but not at 21 weeks of age (P = 0.03). Blood glucose concentrations did not differ between the treatments (P>0.10). There was a significant difference in mortality between treatments (P = 0.000), with more death in aviary reared birds (5.52%) compared to cage birds (2.48%). The higher mortality of aviary-reared birds indicates a negative effect of aviary rearing on bird welfare, whereas the higher duration of alert behavior suggests a positive effect of aviary rearing. 相似文献
995.
996.
Evaluation of coffee reference genes for relative expression studies by quantitative real-time RT-PCR 总被引:1,自引:0,他引:1
Fernanda Cruz Samara Kalaoun Paula Nobile Carlos Colombo Juliana Almeida Leila M. G. Barros Eduardo Romano Maria Fátima Grossi-de-Sá Maité Vaslin Marcio Alves-Ferreira 《Molecular breeding : new strategies in plant improvement》2009,23(4):607-616
Accuracy in quantitative real-time polymerase chain reaction (qPCR) requires the use of stable endogenous controls. Normalization
with multiple reference genes is the gold standard, but their identification is a laborious task, especially in species with
limited sequence information. Coffee (Coffea ssp.) is an important agricultural commodity and, due to its economic relevance, is the subject of increasing research in
genetics and biotechnology, in which gene expression analysis is one of the most important fields. Notwithstanding, relatively
few works have focused on the analysis of gene expression in coffee. Moreover, most of these works have used less accurate
techniques such as northern blot assays instead of more accurate techniques (e.g., qPCR) that have already been extensively
used in other plant species. Aiming to boost the use of qPCR in studies of gene expression in coffee, we uncovered reference
genes to be used in a number of different experimental conditions. Using two distinct algorithms implemented by geNorm and
Norm Finder, we evaluated a total of eight candidate reference genes (psaB, PP2A, AP47, S24, GAPDH, rpl39, UBQ10, and UBI9) in four different experimental sets (control versus drought-stressed leaves, control versus drought-stressed roots, leaves
of three different coffee cultivars, and four different coffee organs). The most suitable combination of reference genes was
indicated in each experimental set for use as internal control for reliable qPCR data normalization. This study also provides
useful guidelines for reference gene selection for researchers working with coffee plant samples under conditions other than
those tested here.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
997.
Joaquim Manoel da Silva Poliana Fernanda Giachetto Luiz Otávio Campos da Silva Leandro Carrijo Cintra Samuel Rezende Paiva Alexandre Rodrigues Caetano Michel Eduardo Beleza Yamagishi 《PloS one》2015,10(8)
High density genotyping panels have been used in a wide range of applications. From population genetics to genome-wide association studies, this technology still offers the lowest cost and the most consistent solution for generating SNP data. However, in spite of the application, part of the generated data is always discarded from final datasets based on quality control criteria used to remove unreliable markers. Some discarded data consists of markers that failed to generate genotypes, labeled as missing genotypes. A subset of missing genotypes that occur in the whole population under study may be caused by technical issues but can also be explained by the presence of genomic variations that are in the vicinity of the assayed SNP and that prevent genotyping probes from annealing. The latter case may contain relevant information because these missing genotypes might be used to identify population-specific genomic variants. In order to assess which case is more prevalent, we used Illumina HD Bovine chip genotypes from 1,709 Nelore (Bos indicus) samples. We found 3,200 missing genotypes among the whole population. NGS re-sequencing data from 8 sires were used to verify the presence of genomic variations within their flanking regions in 81.56% of these missing genotypes. Furthermore, we discovered 3,300 novel SNPs/Indels, 31% of which are located in genes that may affect traits of importance for the genetic improvement of cattle production. 相似文献
998.
999.
Growth of Acetobacterium woodii and Clostridium sporogenes was studied in the presence of water-immiscible solvents. Nitrogen purging, vacuum distillation or distillation under nitrogen were all suitable as methods to remove oxygen from the solvents, since growth rates and yields of A. woodii were unaffected in the presence of tetradecane which had been degassed by these methods. Varying the solvent volume from 20% to 80% of the culture volume had little effect on growth rate of A. woodii. A.woodii was relatively sensitive to organic solvents since growth was inhibited by alkanes with logP(octanol/water) values below 7.1. C. sporogenes was less solvent sensitive, since it grew without inhibition when the logP of the solvent was > or = 6.6. Nevertheless, both A. woodii and C. sporogenes were more sensitive to solvent polarity than aerobic bacteria. 相似文献
1000.
Vander José das Neves Ana Paula Tanno Tatiana Sousa Cunha Tiago Fernandes Vinicius Guzzoni Carlos Alberto da Silva Edilamar Menezes de Oliveira Maria José Costa Sampaio Moura Fernanda Klein Marcondes 《Life sciences》2013,92(20-21):1029-1035
AimsThis study was performed to assess isolated and combined effects of nandrolone and resistance training on the blood pressure, cardiac electrophysiology, and expression of the β1- and β2-adrenergic receptors in the heart of rats.Main methodsWistar rats were randomly divided into four groups and submitted to a 6-week treatment with nandrolone and/or resistance training. Cardiac hypertrophy was accessed by the ratio of heart weight to the final body weight. Blood pressure was determined by a computerized tail-cuff system. Electrocardiography analyses were performed. Western blotting was used to access the protein levels of the β1- and β2-adrenergic receptors in the right atrium and left ventricle.Key findingsBoth resistance training and nandrolone induced cardiac hypertrophy. Nandrolone increased systolic blood pressure depending on the treatment time. Resistance training decreased systolic, diastolic and mean arterial blood pressure, as well as induced resting bradycardia. Nandrolone prolonged the QTc interval for both trained and non-trained groups when they were compared to their respective vehicle-treated one. Nandrolone increased the expression of β1- and β2-adrenergic receptors in the right atrium for both trained and non-trained groups when they were compared to their respective vehicle-treated one.SignificanceThis study indicated that nandrolone, associated or not with resistance training increases blood pressure depending on the treatment time, induces prolongation of the QTc interval, and increases the expression of β1- and β2-adrenergic receptors in the cardiac right atrium, but not in the left ventricle. 相似文献