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排序方式: 共有85条查询结果,搜索用时 46 毫秒
31.
Magnus CJ Lee PH Atasoy D Su HH Looger LL Sternson SM 《Science (New York, N.Y.)》2011,333(6047):1292-1296
Ionic flux mediates essential physiological and behavioral functions in defined cell populations. Cell type-specific activators of diverse ionic conductances are needed for probing these effects. We combined chemistry and protein engineering to enable the systematic creation of a toolbox of ligand-gated ion channels (LGICs) with orthogonal pharmacologic selectivity and divergent functional properties. The LGICs and their small-molecule effectors were able to activate a range of ionic conductances in genetically specified cell types. LGICs constructed for neuronal perturbation could be used to selectively manipulate neuron activity in mammalian brains in vivo. The diversity of ion channel tools accessible from this approach will be useful for examining the relationship between neuronal activity and animal behavior, as well as for cell biological and physiological applications requiring chemical control of ion conductance. 相似文献
32.
Ercüment Aksakal Deniz Ekinci Orhan Erdo?an ?ükrü Beydemir Zuhal Al?m Saltuk Bu?rahan Ceyhun 《Livestock Science》2011,141(1):69-75
The objective of this study was to determine the effects of stocking density on the activity of glucose 6-phosphate dehydrogenase (G6PD), 6-phosphogluconate dehydrogenase (6PGD) and glutathione reductase (GR) enzymes in liver, muscle, gill and kidney tissues of rainbow trout. Fish were reared at different stocking densities (15 kg/m3, 20 kg/m3, 25 kg/m3 and 30 kg/m3). After adaptation period of 30 days, the experiment was carried out for two months. Stocking density of the control group was 15 kg/m3. Increasing stocking density caused inhibition in the activities of the enzymes except for kidney G6PD and 6PGD. Activity of both pentose phosphate pathway enzymes unexpectedly increased only in kidney whereas inhibition was observed in other tissues. Since the most powerful and gradual attenuation was observed in muscle tissue for all enzymes, we performed quantitative Real Time PCR to examine the expression of heat shock protein (Hsp70) gene in muscle in order to understand whether the decrease in enzyme activities is associated with stress. The mRNA expression data showed that Hsp70 expression levels significantly elevated at 25 kg/m3 and 30 kg/m3 stocking densities. Overall results indicate that increasing stocking density blocks the activity of metabolic and antioxidant enzymes and causes considerable stress in rainbow trout. The most susceptible tissue to increasing stocking density was observed to be the muscle. 相似文献
33.
Caroline Utermann Vivien A. Echelmeyer Ernest Oppong-Danquah Martina Blümel Deniz Tasdemir 《Marine drugs》2021,19(1)
It is widely accepted that the commensal gut microbiota contributes to the health and well-being of its host. The solitary tunicate Ciona intestinalis emerges as a model organism for studying host–microbe interactions taking place in the gut, however, the potential of its gut-associated microbiota for marine biodiscovery remains unexploited. In this study, we set out to investigate the diversity, chemical space, and pharmacological potential of the gut-associated microbiota of C. intestinalis collected from the Baltic and North Seas. In a culture-based approach, we isolated 61 bacterial and 40 fungal strains affiliated to 33 different microbial genera, indicating a rich and diverse gut microbiota dominated by Gammaproteobacteria. In vitro screening of the crude microbial extracts indicated their antibacterial (64% of extracts), anticancer (22%), and/or antifungal (11%) potential. Nine microbial crude extracts were prioritized for in-depth metabolome mining by a bioactivity- and chemical diversity-based selection procedure. UPLC-MS/MS-based metabolomics combining automated (feature-based molecular networking and in silico dereplication) and manual approaches significantly improved the annotation rates. A high chemical diversity was detected where peptides and polyketides were the predominant classes. Many compounds remained unknown, including two putatively novel lipopeptides produced by a Trichoderma sp. strain. This is the first study assessing the chemical and pharmacological profile of the cultivable gut microbiota of C. intestinalis. 相似文献
34.
35.
Ayşe Kılıc Hakan Kalender Hatice Eroksuz Adile Muz Bülent Tasdemir 《Tropical animal health and production》2013,45(7):1525-1531
This study used cultures, polymerase chain reaction (PCR), and immunoperoxidase to examine samples from 216 lungs from sheep and lambs with macroscopic pneumonia lesions for the presence of Mycoplasma species. DNA was extracted from lung tissue samples and broth cultures with the help of a DNA extraction kit and replicated using genus-specific and species-specific primers for mycoplasma. The lung samples were examined by the immunoperoxidase method using hyperimmune Mycoplasma ovipneumoniae serum. The randomly amplified polymorphic DNA (RAPD) test was used for the molecular typing of M. ovipneumoniae isolates. Mycoplasma was isolated in the cultures of 80 (37.03 %) of a total of 216 lung samples. Genus-specific mycoplasma DNA was identified by PCR in 96 (44.44 %) samples in broth cultures and 36 (16.66 %) directly in the lung tissue. Of these 96 cases in which genus-specific identification was made, 57 (59.37 %) were positive for reaction with species-specific primers for M. ovipneumoniae and 31 (32.29 %) for Mycoplasma arginini. The DNA of neither of the latter two species could be identified in the remaining eight samples (8.33 %) where mycoplasma had been identified. As for the immunoperoxidase method, it identified M. ovipneumoniae in 61 of 216 lung samples (28 %). Positive staining was concentrated in the bronchial epithelium cell cytoplasm and cell surface. RAPD analysis resulted in 15 different profiles. Our results suggest that PCR methods could be successfully used in the diagnosis of mycoplasma infections as an alternative to culture method and identifying this agent at the species level. 相似文献
36.
In this study, Nylon 66/Polyester (Ny 66/PET) hybrid cord design and production was investigated to obtain new cord with better
performance than conventional cord. The factors affecting cord properties and cord production process were examined. Taguchi
design of experiment method was implemented in order to minimize the required number of experiments. Different sets of 4 reference
cords conventionally used in tyre industry were prepared and resorcinol-formaldehyde-latex (RFL) treated in order to make
a comparison of performance. Mechanical and thermal properties of hybrid cords were measured and compared with the values
of reference cords. It was found that the twist level of high modulus PET component in the hybrid cords should be the same
or above of the nylon in order to obtain maximum tensile strength. It was observed that shrinkage values of hybrid cords varied
between PET and Ny 66 reference cords. Moreover, for all treated hybrid cords, satisfactory cord-rubber adhesion values were
obtained by using double dip adhesion system. 相似文献
37.
Genetic mapping and inheritance of Russian wheat aphid resistance gene in accession IG 100695 下载免费PDF全文
Fatma Aykut Tonk Deniz İştipliler Muzaffer Tosun Ferit Turanli Hülya İlbi Mehmet Çakir 《Plant Breeding》2016,135(1):21-25
The Russian wheat aphid (RWA), Diuraphis noxia (Kurdjumov), is an important pest of small‐grain cereals, particularly wheat, worldwide. The most efficient strategy against the RWA is to identify sources of resistance and to introduce them into susceptible wheat genotypes. This study was conducted to determine the mode of inheritance of the RWA resistance found in ICARDA accession IG 100695, to identify wheat microsatellite markers closely linked to the gene and to map the chromosomal location of the gene. Simple sequence repeat (SSR) marker scores were identified in a mapping population of 190 F2 individuals and compared, while phenotypic screening for resistance was performed in F2 : 3 families derived from a cross between ‘Basribey’ (susceptible) and IG 100695 (resistant). Phenotypic segregation of leaf chlorosis and rolling displayed the effect of a single dominant gene, temporarily denoted Dn100695, in IG 100695. Dn100695 was mapped on the short arm of chromosome 7D with four linked SSR markers, Xgwm44, Xcfd14, Xcfd46 and Xbarc126. Dn100695 and linked SSR markers may be useful for improving resistance for RWA in wheat breeding. 相似文献
38.
Mustafa Durmus Deniz Ayas Mehmet Aydin Ali Riza Kosker Yilmaz Ucar Yesim Ozogul 《Journal Of Aquatic Food Product Technology》2018,27(6):749-758
The present paper examines the impacts of gender and season variables on the nutritional composition and metal levels of warty crab caught in the central Black Sea region (Ordu). Crab samples were caught over four seasons, using gillnets, trammel net, and SCUBA diving. Results of chemical analysis showed that protein, lipid, moisture, and total mineral substance level ranges of male crabs were 20.45–22.64%, 0.95–1.27%, 75.44–77.09%, and 1.63–2.08%, while these ranges in female individuals were determined as 19.45–21.46%, 0.63–0.92%, 75.44–77.44%, and 2.08–3.28%, respectively. Macro and trace element levels in crab muscle tissue were determined as K > P > Na > Ca > Mg and Zn > Fe > Cu > Mn > Se > Ni > Mo > Co, respectively. Cd and Pb levels in crab muscle tissue were determined to be lower than the limit values given in codices independent of the seasonal variables. However, as the levels were found to be above the limit values, metal concentrations in crabs were also evaluated based on provisional tolerable daily intake and provisional tolerable weekly intake limits. 相似文献
39.
Antnio Pinto-Almeida Anelize Bauermeister Luca Luppino Inês R. Grilo Juliana Oliveira Joana R. Sousa Daniel Petras Clara F. Rodrigues Alejandra Prieto-Dav Deniz Tasdemir Rita G. Sobral Susana P. Gaudêncio 《Marine drugs》2022,20(1)
The Estremadura Spur pockmarks are a unique and unexplored ecosystem located in the North Atlantic, off the coast of Portugal. A total of 85 marine-derived actinomycetes were isolated and cultured from sediments collected from this ecosystem at a depth of 200 to 350 m. Nine genera, Streptomyces, Micromonospora, Saccharopolyspora, Actinomadura, Actinopolymorpha, Nocardiopsis, Saccharomonospora, Stackebrandtia, and Verrucosispora were identified by 16S rRNA gene sequencing analyses, from which the first two were the most predominant. Non-targeted LC-MS/MS, in combination with molecular networking, revealed high metabolite diversity, including several known metabolites, such as surugamide, antimycin, etamycin, physostigmine, desferrioxamine, ikarugamycin, piericidine, and rakicidin derivatives, as well as numerous unidentified metabolites. Taxonomy was the strongest parameter influencing the metabolite production, highlighting the different biosynthetic potentials of phylogenetically related actinomycetes; the majority of the chemical classes can be used as chemotaxonomic markers, as the metabolite distribution was mostly genera-specific. The EtOAc extracts of the actinomycete isolates demonstrated antimicrobial and antioxidant activity. Altogether, this study demonstrates that the Estremadura Spur is a source of actinomycetes with potential applications for biotechnology. It highlights the importance of investigating actinomycetes from unique ecosystems, such as pockmarks, as the metabolite production reflects their adaptation to this habitat. 相似文献
40.
Anthony R. D’Amato Nicholas J. Schaub Jesus M. Cardenas Erich Franz Deniz Rende Alexis M. Ziemba Ryan J. Gilbert 《Fibers and Polymers》2017,18(3):483-492
Electrospun fiber scaffolds crafted from polyesters are studied extensively for potential tissue engineering applications. For translation of electrospun fibers into the clinic, the FDA requires analysis and quantification of any organic solvent that may be retained in the fibers since many organic solvents can negatively affect cells and tissues. If a significant amount of solvent is retained, then developing procedures for efficient solvent removal may enhance the clinical potential of these materials. In this study we use fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), and nuclear magnetic resonance spectroscopy (NMR) to analyze solvent retention. A correlative analysis shows that both FTIR and TGA accurately predicted retention of two different solvents (HFP and chloroform) in our electrospun PLLA scaffolds, thus validating these procedures. We also assess the efficacy of various fiber treatment methods to facilitate organic solvent removal and conclude that submersion in 70 % ethanol and heat treatment at 100 °C were the most efficient methods of removing solvent from electrospun PLLA fibers. 相似文献