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31.
New dammarane-type saponins from the galls of Sapindus mukorossi 总被引:2,自引:0,他引:2
Kuo YH Huang HC Yang Kuo LM Hsu YW Lee KH Chang FR Wu YC 《Journal of agricultural and food chemistry》2005,53(12):4722-4727
Five new dammarane-type saponins, 3beta,7beta,20(S),22-tetrahydroxydammar-24-ene-3-O-alpha-l-rhamnopyranosyl-(1-->2)-beta-D-glucopyranoside, 3beta,7beta,20(S),22,23-pentahydroxydammar-24-ene-3-O-alpha-l-rhamnopyranosyl-(1-->2)-beta-D-glucopyranoside, 3beta,7beta,20(S),22,25-pentahydroxydammar-23-ene-3-O-alpha-l-rhamnopyranosyl-(1-->2)-beta-D-glucopyranoside, 25-methoxy-3beta,7beta,20(S),22-tetrahydroxydammar-23-ene-3-O-alpha-l-rhamnopyranosyl-(1-->2)-beta-D-glucopyranoside, and 25-methoxy-3beta,7beta,20(R)-trihydroxydammar-23-ene-3-O-alpha-l-rhamnopyranosyl-(1-->2)-beta-D-glucopyranoside, named sapinmusaponins A (1), B (2), C (3), D (4), and E (5), respectively, together with three known phenylpropanoid glycosides (6-8), were isolated from the galls of Sapindus mukorossi. The structures of these saponins were elucidated on the basis of spectroscopic analyses and chemical methods. Preliminary bioassay data revealed that saponins 1 and 3-5 showed moderate cytotoxic activity (ED50 approximately 9-18 microg/mL) against human tumor cell lines (Hepa59T/VGH, NCI, HeLa, and Med) and that 1-5 were inactive in vitro against HIV replication in H9 lymphocytes. 相似文献
32.
Kuo CC Chiang W Liu GP Chien YL Chang JY Lee CK Lo JM Huang SL Shih MC Kuo YH 《Journal of agricultural and food chemistry》2002,50(21):5850-5855
An activity-directed fractionation and purification process was used to identify the antioxidative components of adlay hulls. Hulls of adlay (Coix lachryma-jobi L. var. ma-yuen Stapf) were extracted with methanol and then separated into water, 1-butanol, ethyl acetate, and hexane fractions. The 1-butanol-soluble fraction exhibited greater capacity to scavenge 2,2'-diphenyl-1-picrylhydrazyl (DPPH) radicals when compared with fractions soluble in water, ethyl acetate, and hexane phases. The 1-butanol fraction was then subjected to separation and purification using Diaion HP-20 chromatography, silica gel chromatography, and HPLC. Six compounds showing strong antioxidant activity were identified by spectroscopic methods ((1)H NMR, (13)C NMR, IR, and MS) and by comparison with authentic samples to be coniferyl alcohol (1), syringic acid (2), ferulic acid (3), syringaresinol (4), 4-ketopinoresinol (5), and a new lignan, mayuenolide (6). 相似文献
33.
Potent fibrinolytic enzyme from a mutant of Bacillus subtilis IMR-NK1 总被引:10,自引:0,他引:10
A mutant of Bacillus subtilis IMR-NK1, which is used for the production of domestic "natto" in Taiwan, produced high fibrinolytic enzyme activity by solid-state fermentation using wheat bran as medium. In addition, a strong fibrinolytic enzyme was purified from the cultivation media. The purified enzyme was almost homogeneous, as examined by SDS-PAGE and capillary electrophoresis. The enzyme had an optimal pH of 7.8, an optimal temperature of 55 degrees C, and a K(m) of 0.15% for fibrin hydrolysis. The molecular mass estimated by gel filtration was 31.5 kDa, and the isoelectric point estimated by isoelectric focusing electrophoresis was 8.3. The enzyme also showed activity for hydrolysis of fibrinogen, casein, and several synthetic substrates. Among the synthetic substrates, the most sensitive substrate was N-succinyl-Ala-Ala-Pro-Phe-pNA. PMSF and NBS almost completely inhibited the activity of the enzyme. These results indicate that the enzyme is a subtilisin-like serine protease, similar to nattokinase from Bacillus natto. 相似文献
34.
Lo SF Mulabagal V Chen CL Kuo CL Tsay HS 《Journal of agricultural and food chemistry》2004,52(23):6916-6919
This study was performed to investigate the free radical scavenging active components from in vitro propagated medicinal herbs of the genus Dendrobium, namely, Dendrobium tosaense Makino and Dendrobium moniliforme SW, using a 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical antioxidative assay. Seeds of the capsules derived after 12 weeks of hand-pollination germinated asymbiotically (50-74%) on half-strength Murashige and Skoog's (MS) basal medium with 3% sucrose and solidified with 0.9% Difco agar. Active growth in the germinated seedlings was achieved by reculturing on full-strength MS basal medium supplemented with 8% banana homogenate, 8% potato homogenate, 8% coconut water, 1.5% sucrose, and 0.9% Difco agar. Healthy plantlets transferred to plastic trays containing moss or moss and tree fern successfully acclimatized (84-100%) in the greenhouse. Extracts were prepared from plants grown in the greenhouse for a period of 6 months. Methanolic extracts of D. tosaense and D. moniliforme scavenged DPPH at 95.9 and 83.4%, respectively, at a concentration of 0.4 mg/mL. Therefore, methanolic solubles of D. tosaense and D. moniliforme were subjected to bioguided fractionation and separation by column chromatographic methods individually. After chromatographic separation of these crude extracts, the obtained fractions (Dm 1, Dm 2, Dm 3, Dt 1, Dt 2, and Dt 3) were tested for their activity. Among them, fractions Dm 2 and Dt 1 showed significant antioxidant activity by DPPH radical antioxidative assay. Active fractions were purified further by column chromatography and resulted in identification of the antioxidant components alkyl ferulates from D. moniliforme and quercetin from D. tosaense. 相似文献
35.
Sandra A. Loftus BA Jill M. Montplaisir BS Jing-wen Kuo MS Dale P. DeVore PhD 《Journal of Equine Veterinary Science》1988,8(2)
A standardized investigation was conducted to compare the biophysical properties of hyaluronate products used in the treatment of joint dysfunction in horses. Results showed that two of the five products, Hyvisc® and Hylartin®V, contained higher-weight molecular hyaluronate (greater than 1.5×106). Other investigations have shown that higher molecular weight hyaluronate is effective in providing physical resistance to shear, in stimulating endogenous hyaluronate synthesis, and in inhibiting excess cell proliferation which may be associated with synovial pannus formation. It is suggested that the therapeutic benefits of hyaluronate products may be dependent on the molecular size of the hyaluronate molecules. Higher molecular weight hyaluronate products would be expected to be more effective than lower molecular hyaluronate products in providing therapeutic benefits. 相似文献
36.
Heading Chinese cabbage (Brassica campestris ssp. pekinensis Rupr.) grown with low Ca or B developed dark tan lesions near the leaf margins. A synergistic effect of low Ca and low B accompanied the development of this symptom. Plants grown under humid conditions were free of tipburn. Plants grown under less humidity developed tipburn. Total chemical analysis revealed a steady decrease in total Ca from the outer to the inner leaves. Fractional chemical analysis showed 7 times more water-soluble Ca in the outer than in the inner leaves, and 2 times more 1 N NaCl-soluble Ca in the outer than in inner leaves. Threshold concentration of water-soluble forms of Ca for tipburn was around 3.0 mg/g dry weight. Data suggest that root pressure flow is required to move adequate amounts of water-soluble Ca to the wrapper leaves to prevent tipburn of Chinese cabbage. 相似文献
37.
We report the detection of an earthquake by a space-based measurement. The Gravity Recovery and Climate Experiment (GRACE) satellites observed a +/-15-microgalileo gravity change induced by the great December 2004 Sumatra-Andaman earthquake. Coseismic deformation produces sudden changes in the gravity field by vertical displacement of Earth's layered density structure and by changing the densities of the crust and mantle. GRACE's sensitivity to the long spatial wavelength of gravity changes resulted in roughly equal contributions of vertical displacement and dilatation effects in the gravity measurements. The GRACE observations provide evidence of crustal dilatation resulting from an undersea earthquake. 相似文献
38.
Chein-Yao Liao Mei-Ya Chen Yuh-Kun Chen Tien-Cheng Wang Zong-Ming Sheu Ker-Chung Kuo Pi-Fang Linda Chang Kuang-Ren Chung Miin-Huey Lee 《European journal of plant pathology / European Foundation for Plant Pathology》2012,133(3):599-608
Colletotrichum acutatum causes anthracnose on peppers (Capsicum spp.), resulting in severe yield losses in Taiwan. Fungal isolates Coll-153, Coll-365 and Coll-524 collected from diseased peppers were found to differ in pathogenicity. Pathogenicity assays on various index plants revealed that Coll-524 was highly virulent and Coll-153 was moderately virulent to three commercially available pepper cultivars. Both isolates induced anthracnose lesions and produced abundant conidia. Coll-365 was only weakly virulent on pepper fruit, where it caused small lesions and hardly produced conidia on pepper fruit. However, Coll-365 was highly pathogenic to tomato fruit and mango leaves, where it caused anthracnose lesions and formed acervuli and conidia. All three isolates showed similar abilities in the attachment and germination of conidia, formation of highly branched hyphae and appressoria, penetration of cuticles, and infection of epidermal cells on chili peppers. Coll-365 accumulated less turgor pressure in appressoria but produced higher levels of cutinase and protease activity than Coll-153 and Coll-524 did. All three isolates invaded the neighbouring cells through plasmodesmata in chili peppers and showed similar pectinase or cellulase activities in culture. However, the most virulent strain Coll-524 expressed stronger laccase activity and was more resistant to capsaicin compared to Coll-153 and Coll-365. The three isolates are different in numbers and sizes of double-stranded RNAs. Depending on the cultivar genotypes, cellular resistance of chili pepper to C. acutatum might rely on the ability to restrict penetration, colonization, or conidiation of the pathogen. We conclude that the differences in pathogenicity among the three C. acutatum isolates of pepper are attributed to their ability to colonize the host plant. 相似文献
39.
40.
Ming-Shien Yen Mu-Cheng Kuo Jyh-Hong Wu Cheng-Wei Yeh Wei-Yu Lai 《Fibers and Polymers》2013,14(9):1432-1439
A series of hybrid materials composed of boehmite/silica/thiazole dyes and prepared via the sol-gel process is synthesized from aluminum isopropoxide (AIP) and tetraethoxysilane using heteroaryl 2-amino-thiazole azo dyes. Heterocyclic 2-amino-thiazole azo dyes undergo a hydrolysis-condensation reaction with an appropriate proportion of AIP under a catalyst, at a constant ratio of vinyltriethoxysilane (VTES) and tetraethoxysilane (TEOS). The structures of these hybrid materials composed of boehmite/silica/thiazole dyes are characterized using Fourier transform infrared (FT-IR) analysis. The surface morphology of polyethylene terephthalate (PET) fabrics is evaluated using scanning electron microscopy (SEM). SEM images show uniform dyeing of the PET fabrics that confirms the reaction of the hybrid materials with the PET fabrics. The water contact angle, washing fastness, color evenness, air permeability, and warmth retention of the PET fabrics dyed with hybrid materials composed of boehmite/silica/thiazole dyes are evaluated. The evaluation results indicate improved warmth retention property and good water repellency. 相似文献