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201.
Soo-Hyeon Kim Byung-Joon Seung Seung-Hee Cho Ha-Young Lim Min-Kyung Bae Kyung-Yeon Eo Yong-Gu Yeo Jang-Won Son Jung-Hyang Sur 《Journal of veterinary diagnostic investigation》2021,33(2):366
A 36-y-old white rhinoceros (Ceratotherium simum) was presented with respiratory distress, sanguineous vaginal exudate, and anorexia. The clinical signs progressed over 40 d, and the rhinoceros died. Autopsy revealed significant ascites; a unilateral, 12.5-cm diameter, polypoid mass in the left ovary; a white, firm transmural mass in the right uterine horn; a white, friable mass in the lung; and white-to-tan, friable small nodules in the diaphragm. Histologic examination revealed similar neoplastic cells in the masses in all 4 locations, composed predominantly of epithelial cells proliferating in a tubulopapillary pattern with significant nuclear atypia and numerous atypical mitotic figures (18–42 per 2.37 mm2). Immunohistochemistry for CK7 (cytokeratin 7) and CK20 (cytokeratin 20) suggest that the ovarian, pulmonary, and diaphragmatic lesions were of ovarian origin and that the ovary was the primary tumor site. 相似文献
202.
Wood Ash Effects on Soil Solution and Nutrient Budgets in A Willow Bioenergy Plantation 总被引:1,自引:0,他引:1
Park Byung Bae Yanai Ruth D. Sahm James M. Ballard Benjamin D. Abrahamson Lawrence P. 《Water, air, and soil pollution》2004,159(1):209-224
The management of wood ash is an important factor in the environmental and economic analysis of wood burning. Wood ash can be applied to energy crops as a fertilizer, which can help replace nutrients removed during harvest. The objectives of this study were to examine the temporal and spatial dynamics of nutrient elements applied in wood ash to an intensively cultured, short-rotation willow bioenergy system. Wood ash was applied at the rates of 10 and 20 Mg ha–1 yr–1 to coppiced willow, Salix purpurea, clone SP3, from 1992 to 1994. The relative abundance of nutrients in applied wood ash was Ca > K > Mg > P > N. There was little effect of wood ash on N or P concentrations in soil solution measured at 20 and 40 cm depth. Soil solution concentrations of base cations were elevated in the last two years of the study by 30 to 90%, depending on the element and treatment, in plots receiving wood ash. Wood ash treatments had little influence on foliar leaching. Wood ash treatment also had few significant effects on willow growth or on the contents of N, P, K, Ca, and Mg in foliage and stems. The addition of P, K, Ca, and Mg in wood ash was more than enough to compensate for harvest removals and leaching losses. This study demonstrated that wood ash can supply most nutrients removed during harvest in willow plantations, with the exception of N, without adverse effects on groundwater or vegetation. 相似文献
203.
Chuan-Ling Si Jin-Kyu Kim Young-Soo Bae Peng-Tao Liu Zhong Liu 《Wood Science and Technology》2011,45(1):5-13
The methanol (MeOH) extract of Populus ussuriensis Kom. bark was analyzed for antioxidant assessing by 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging potential. Among
fractions using several solvents, the ethyl acetate (EtOAc) soluble fraction, which showed strong antioxidant activity (IC50 2.02 ± 0.01 μg/ml), was further purified by Thin layer chromatography (TLC) guided Sephadex LH-20 column chromatography.
Three known phenolic glucosides, picein (I), salicortin (II), grandidentatin (III), and that of a new, 2-hydroxycyclohexyl-4′-O-p-coumaroyl-β-d-glucopyranoside (isograndidentatin A), were isolated and their structures were elucidated on the basis of physiochemical
and spectroscopic methods. This was the first report of the chemical composition of P. ussuriensis bark. Phenolic glucosides III and IV exhibited strong antioxidant activities, with IC50 values 6.73 ± 0.01 and 6.69 ± 0.01 μM, respectively, comparable to the control (α-tocopherol, IC50 6.80 ± 0.01 μM). P. ussuriensis bark EtOAc-soluble fraction and compounds III and IV could be used as biopreservatives in food applications as well as for cosmetic and medicinal preparations, to alleviate oxidative
stress. 相似文献
204.
205.
Choi JS Kim JS Byun IS Lee DH Lee MJ Park BH Lee C Yoon D Cheong H Lee KH Son YW Park JY Salmeron M 《Science (New York, N.Y.)》2011,333(6042):607-610
Graphene produced by exfoliation has not been able to provide an ideal graphene with performance comparable to that predicted by theory, and structural and/or electronic defects have been proposed as one cause of reduced performance. We report the observation of domains on exfoliated monolayer graphene that differ by their friction characteristics, as measured by friction force microscopy. Angle-dependent scanning revealed friction anisotropy with a periodicity of 180° on each friction domain. The friction anisotropy decreased as the applied load increased. We propose that the domains arise from ripple distortions that give rise to anisotropic friction in each domain as a result of the anisotropic puckering of the graphene. 相似文献
206.
Dyeing and color fastness properties of a reactive disperse dye containing an acetoxyethylsulphone group on PET, Nylon, silk
and N/P fabrics were examined. The reactive disperse dye exhibited almost the same dyeing properties on PET fabric as a conventional
disperse dye except the level of dye uptake. The most appropriate pH and dyeing temperature for the dyeing of Nylon fabric
were 7 and 100°C respectively. The build-up on Nylon fabric was good and various color fastnesses were good to excellent due
to the formation of the covalent bond. Application of the reactive disperse dye on silk fabric at pH 9 and 80°C yielded optimum
color strength. The rate of dyeing on Nylon fabric was faster than that on PET fabric when both fabrics were dyed simultaneously
in a dye bath, accordingly color strength of the dyed Nylon was higher. The reactive disperse dye can be applied for one-step
and one-bath dyeing of N/P mixture fabric with good color fastness. 相似文献
207.
Sung Eun Kim Yong Woo Cho Eun Jung Kang Ick Chan Kwon Eunhee Bae Lee Jung Hyun Kim Hesson Chung Seo Young Jeong 《Fibers and Polymers》2001,2(2):64-70
A three-dimensional, porous collagen/chitosan complex sponge was prepared to closely simulate basic extracellular matrix (ECM)
constitutes, collagen and glycosaminoglycan. The complex sponge was prepared by a lyophilization method and had the regular
network with highly porous structure, suitable for cell adhesion and growth. The pores were well interconnected, and their
distribution was fairly homogeneous. The complex sponge was crosslinked using 1-ethyl-3-(3-dimethyl aminopropyl) carbodiimide
(EDC) and N-hydroxysuccinimide (NHS) to increase its biological stability and enhance its mechanical properties. The crosslinking
medium had a great effect on the inner structure of the sponge. The homogeneous, porous structure of the sponge was remarkably
collapsed in an aqueous crosslinking medium. However, the morphology of the sponge remained almost intact in a water/ethanol
mixture crosslinking milieu. Mechanical properties of the collagen/chitosan sponge were significantly enhanced by EDC-mediated
crosslinking. The potential of the sponge as a scaffold for tissue engineering was investigated using a Chinese hamster ovary
cell (CHO-K1) line. 相似文献
208.
Lee Ji Min Park Youn Shik Kum Donghyuk Jung Younghun Kim Bomchul Hwang Soon Jin Kim Hyun Bae Kim Chulgoo Lim Kyoung Jae 《Paddy and Water Environment》2014,12(1):169-183
Aquatic ecosystems are threatened by increasing variability in the hydrologic responses. In particular, the health of river ecosystems in steeply sloping watersheds is aggravated due to soil erosion and stream depletion during dry periods. This study suggested and assessed a method to improve the adaptation ability of a river system in a steep watershed. For this, this study calibrated soil and water assessment tool (SWAT) for runoff and sediment, and quantified the changes in hydrologic responses such as groundwater recharge rate soil erosion and baseflow according to two scenarios for adjustment of the watershed slope (steep to mild). Here, one scenario was set by three measured slopes, and the other was set by fixing the entire watershed slopes with 5 %. Moreover, SWAT and web-based hydrograph analysis tool (WHAT) models were applied to estimate groundwater recharge, soil erosion, and baseflow in the Haean-myeon watershed in South Korea. The results show that the reduction of watershed slope increased groundwater recharge and baseflow, and decreased sediment. Specifically, groundwater recharge rate was increased from 257.10 to 364.60 mm, baseflow was increased from 0.86 to 1.19 m3/s, and sediment was decreased from 194.6 to 58.1 kg/km2. Based on these results, the suggested method will positively contribute to aquatic ecosystems and farming environments in a steeply sloping watershed due to improvements in the quantity and quality of river water. 相似文献
209.
Characterization of storage proteins in wild (Glycine soja) and cultivated (Glycine max) soybean seeds using proteomic analysis 总被引:1,自引:0,他引:1
Natarajan SS Xu C Bae H Caperna TJ Garrett WM 《Journal of agricultural and food chemistry》2006,54(8):3114-3120
A combined proteomic approach was applied for the separation, identification, and comparison of two major storage proteins, beta-conglycinin and glycinin, in wild (Glycine soja) and cultivated (Glycine max) soybean seeds. Two-dimensional polyacrylamide gel electrophoresis (2D-PAGE) with three different immobilized pH gradient (IPG) strips was an effective method to separate a large number of abundant and less-abundant storage proteins. Most of the subunits of beta-conglycinin were well-separated in the pH range 3.0-10.0, while acidic and basic glycinin polypeptides were well-separated in pH ranges 4.0-7.0 and 6.0-11.0, respectively. Although the overall distribution pattern of the protein spots was similar in both genotypes using pH 3.0-10.0, variations in number and intensity of protein spots were better resolved using a combination of pH 4.0-7.0 and pH 6.0-11.0. The total number of storage protein spots detected in wild and cultivated genotypes was approximately 44 and 34, respectively. This is the first study reporting the comparison of protein profiles of wild and cultivated genotypes of soybean seeds using proteomic tools. 相似文献
210.
Yong-Chan Chung Sang Hyeon Kim Jin Cheol Bae Byoung Chul Chun 《Fibers and Polymers》2018,19(6):1157-1165
The bulky and rigid triphenylmethyl group was grafted onto polyurethane (PU) to reduce the molecular attractions between hard segments and to improve the mobility of the PU chain under freezing conditions. The triphenylmethyl-grafted PU exhibited improvement in the cross-link density, solution viscosity, maximum tensile stress, shape recovery at 10 °C, and low temperature flexibility compared with the plain PU. The soft segment melting was not affected by the grafted triphenylmethyl group, whereas the soft segment crystallization disappeared with the increase of the triphenylmethyl group content. The glass transition temperature (Tg) increased with the increase of the triphenylmethyl group content. The rapid increase of the tensile strength and shape recovery at 10 °C resulted from the cross-linking effect, whereas the strain at break and shape retention at -25 °C slightly decreased with the increase of the triphenylmethyl group content. The triphenylmethylgrafted PU displayed an excellent low temperature flexibility even at -50 °C due to the improved mobility of the PU chain compared to ordinary PU. 相似文献