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排序方式: 共有186条查询结果,搜索用时 15 毫秒
21.
Bosiljka Šaravanja Krešimir Malarić Tanja Pušić Darko Ujević 《Fibers and Polymers》2016,17(1):136-142
The aim of this research is to investigate shield effect properties of the fabrics with inox yarns included in the construction, which are used for special professional garments and should protect from electromagnetic microwave irradiation. The investigation was done prior to and after the professional care procedures of dry and wet cleaning in ten cleaning cycles. Shield effect measurements were done on the face and on the back of the fabric, weftwise and warpwise, prior to and after the first, third, fifth, seventh and tenth cycles of dry and wet cleaning, at the frequencies from 0.9 to 2.4 GHz. The results obtained indicated that shield effect of the fabric tested was reduced after professional care procedures, especially so after 5 cycles. The investigations also revealed that shield effect could be considerably enhanced if the inox yarns were incorporated into the fabric in the direction of the warp. 相似文献
22.
Tanja Nurmi Anna-Maija Lampi Laura Nyström Youna Hemery Xavier Rouau Vieno Piironen 《Journal of Cereal Science》2012
Phytosterols and steryl ferulates are bioactive compounds accumulating in the bran and germ of wheat. However, little is known regarding their localisation and composition in the bran layers of the kernel. The aim of this study was to determine the distribution of phytosterols and steryl ferulates in the wheat grain and in the different layers of bran. The wheat fractions, produced by conventional debranning, aleurone separation and a novel electrostatic process, were analysed for phytosterol contents using GC–FID and for steryl ferulate contents using HPLC–UV. The compounds were identified by GC– and LC–MS. Phytosterols and steryl ferulates were concentrated in the bran layers. The steryl ferulates were accumulated in the intermediate layers, whereas the phytosterols were more evenly distributed in the intermediate layers and aleurone cell contents. The phytosterol composition varied within the wheat kernel, while the steryl ferulate composition was similar in different fractions. Sitosterol and campestanyl ferulate were the main compounds. The highest levels of phytosterols (up to 2117 μg/g) and steryl ferulates (up to 703 μg/g) were found in the pearling, aleurone and certain bran fractions. The phytosterol-rich fractions could be utilised in cereal foods to enhance the intake of health-promoting compounds from natural sources. 相似文献
23.
Marine natural products are a diverse, unique collection of compounds with immense therapeutic potential. This has resulted in these molecules being evaluated for a number of different disease indications including the neglected protozoan diseases, human African trypanosomiasis and Chagas disease, for which very few drugs are currently available. This article will review the marine natural products for which activity against the kinetoplastid parasites; Trypanosoma brucei brucei, T.b. rhodesiense and T. cruzi has been reported. As it is important to know the selectivity of a compound when evaluating its trypanocidal activity, this article will only cover molecules which have simultaneously been tested for cytotoxicity against a mammalian cell line. Compounds have been grouped according to their chemical structure and representative examples from each class were selected for detailed discussion. 相似文献
24.
Yousef Dashti Tanja Grkovic Usama Ramadan Abdelmohsen Ute Hentschel Ronald J. Quinn 《Marine drugs》2014,12(5):3046-3059
Two sponge-derived actinomycetes, Actinokineospora sp. EG49 and Nocardiopsis sp. RV163, were grown in co-culture and the presence of induced metabolites monitored by 1H NMR. Ten known compounds, including angucycline, diketopiperazine and β-carboline derivatives 1–10, were isolated from the EtOAc extracts of Actinokineospora sp. EG49 and Nocardiopsis sp. RV163. Co-cultivation of Actinokineospora sp. EG49 and Nocardiopsis sp. RV163 induced the biosynthesis of three natural products that were not detected in the single culture of either microorganism, namely N-(2-hydroxyphenyl)-acetamide (11), 1,6-dihydroxyphenazine (12) and 5a,6,11a,12-tetrahydro-5a,11a-dimethyl[1,4]benzoxazino[3,2-b][1,4]benzoxazine (13a). When tested for biological activity against a range of bacteria and parasites, only the phenazine 12 was active against Bacillus sp. P25, Trypanosoma brucei and interestingly, against Actinokineospora sp. EG49. These findings highlight the co-cultivation approach as an effective strategy to access the bioactive secondary metabolites hidden in the genomes of marine actinomycetes. 相似文献
25.
Tanja Grkovic Johanna S. Blees Magdalena M. Bayer Nancy H. Colburn Cheryl L. Thomas Curtis J. Henrich Megan L. Peach James B. McMahon Tobias Schmid Kirk R. Gustafson 《Marine drugs》2014,12(8):4593-4601
A cell-based high-throughput screen that assessed the cellular stability of a tumor suppressor protein PDCD4 (Programmed cell death 4) was used to identify a new guanidine-containing marine alkaloid mirabilin K (3), as well as the known compounds mirabilin G (1) and netamine M (2). The structures of these tricyclic guanidine alkaloids were established from extensive spectroscopic analyses. Compounds 1 and 2 inhibited cellular degradation of PDCD4 with EC50 values of 1.8 μg/mL and 2.8 μg/mL, respectively. Mirabilin G (1) and netamine M (2) are the first marine natural products reported to stabilize PDCD4 under tumor promoting conditions. 相似文献
26.
Tanja Du?i? Rosemarie Langenfeld-Heyser Andrea Polle 《Soil biology & biochemistry》2009,41(4):742-753
To investigate the role of arbuscular and ectomycorrhizas for growth and nutrition, Douglas fir (Pseudotsuga menziesii), a species capable of establishing both types of symbioses, was used. Seedlings of two varieties of Douglas fir, var. menziesii (DFM) and var. glauca (DFG), differing in biomass production under non-mycorrhizal conditions, were planted in two soils of different nutrient status without preceding Douglas fir cultivation. After 2 years, the abundance of ectomycorrhizas was significantly higher on DFM than on DFG roots and higher in nutrient rich than in poor soil. Independent of the abundance of ectomycorrhiza colonization, roots of both Douglas fir varieties contained in most cases a minimum of six to nine different fungal species identified by ITS sequencing, which displayed both soil- and seed origin-specific patterns. Rhizopogon vinicolor was associated with DFM, whereas Cadophora finlandia, Sebacinaceous sp., Tricholoma sp. and a Tuber sp. were more frequently found on DFG roots. Ectendomycorrhizas were also identified and included under ectomycorrhiza for determination of nutrient relations. Net primary productivity and nitrogen-use efficiency were positively correlated with the degree of ectomycorrhiza colonization of Douglas fir seedlings suggesting that nitrogen accumulation did not keep pace with biomass production despite increased ectomycorrhizal colonization. Phosphorus-use efficiency was negatively correlated with the abundance of arbuscular mycorrhizas, suggesting higher efficiency of these fungi than of ectomycorrhizas for phosphorus supply to the host. DFM, which had higher inherited growth capacities than DFG, displayed higher ectomycorrhizal colonization than DFG. In our experimental design the physiology of the host tree and soil properties, but not the diversity of fungi present on roots, were decisive factors for formation and abundance of ectomycorrhiza. 相似文献
27.
High and low molecular weight glutenin subunits (HMW‐GS and LMW‐GS, respectively) are the main factors determining the viscoelastic properties of wheat dough. The mechanical and viscoelastic properties of 29 samples of wheat kernels differing in HMW‐GS were evaluated with load‐compression tests. Samples were grouped by genotypes differing in HMW‐GS composition (allelic variants: Glu‐A1: null, 1, 2*; Glu‐B1: 7, 7+8, 7+9, 13+16, and 17+18; Glu‐D1: 5+10, 2+12). Groups representing Glu‐A1 1 and 2*; Glu‐B1 7, 7+9 and 17+18; and Glu‐D1 5+10 generally possessed hard grain and showed the largest kernel elasticity values, while those representing subunits Glu‐A1 null; Glu‐B1 7+8; and Glu‐D1 2+12 had soft kernels and showed lower elastic work values. Genotypes possessing HMW‐GS 1, 17+18 and 5+10 gave large SDS‐sedimentation values and better dough viscoelastic properties than those with allelels: null, 7+8, and 2+12. Kernel hardness showed significant correlation with the dough‐strength‐related parameters: SDS‐sedimentation; dough mixing time; and the alveographic parameters, W and P. There was a negative correlation between kernel plastic work and dough mixing time and the dough tenacity/extensibility parameters, P/L. The significant relationship between sedimentation tests and kernel elastic work seems to indicate that elastic work is related to genotype (protein composition). The general tendency was that higher values in kernel elastic work and size corresponded to better dough rheological quality. Mechanical properties of the kernel were significantly related to the elastic behavior measured in a single wheat kernel. The use of the compression test on individual kernels is easy, rapid and nondestructive and therefore seems to show potential use as a rapid tool in breeding to improve wheat quality. 相似文献
28.
Steinberg TA Boettcher IC Matiasek K Hirschvogel K Hartmann K Kunz A Kuntz A Fischer A 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2008,37(2):207-216
BACKGROUND: Inflammation of the central nervous system (CNS) is a frequent condition in cats but etiology often remains unsolved. Routine cerebrospinal fluid (CSF) analysis can be extended through the calculation of the albumin quotient (Q(alb)), a marker of the integrity of the blood-brain barrier (BBB), and IgG index, an estimate of intrathecal IgG synthesis. OBJECTIVES: The purpose of this study was to validate nephelometric methods for CSF protein analysis, and to use the Q(alb) and IgG index to discriminate blood- and brain-derived immunoglobulin fractions in cats with feline infectious peritonitis (FIP). METHODS: Cats presented to our clinic between 2001 and 2005 were included in the study based on clinical and laboratory data and histopathologic findings at necropsy. Cats were grouped as having nonneurologic disease (controls; n=37), brain tumors (n=8), FIP involving the CNS (n=12), and extraneural FIP (n=12). CSF-total protein (TP) was measured and albumin and IgG concentrations were measured in paired CSF/serum samples; Q(alb) and IgG index were calculated. Intraassay and interassay precision of the nephelometric assays were determined using pooled samples. RESULTS: Coefficients of variation for the nephelometric assays ranged from 2.7% to 7.2%. In control cats, CSF-TP concentration ranged from 0.06 to 0.36 g/L, Q(alb) ranged from 0.6 to 5.7 x 10(-3), and IgG index ranged from 0.3 to 0.6. Q(alb) and IgG index were significantly higher in cats with brain tumors and cats with CNS-FIP compared with other groups. Compared with control cats, pleocytosis was evident in 8 of 12 (67%) cats and CSF-TP was increased in 3 of 12 (25%) cats with CNS-FIP. CONCLUSION: Nephelometry is a reliable method for measurement of CSF protein, albumin, and IgG in cats. The Q(alb) and IgG index did not identify a CSF protein pattern specific for BBB dysfunction or intrathecal IgG synthesis in cats with CNS-FIP. 相似文献
29.