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21.
22.
Summary We have succeeded in producing useful interspecific hybrid using ovule-embryo culture between Gypsophila paniculata L. Red Sea and G. manginii, an incompatible combination by ordinary cross breeding methods. The hybrid plant had double flowers with a color of pale purplish pink. Hybrid characteristics of the plant were firmed by observation of plant form, flower type, chromosome number and peroxidase isozyme patterns. 相似文献
23.
Intercontinental spread of a new antibiotic resistance gene on an epidemic plasmid 总被引:10,自引:0,他引:10
T F O'Brien M P Pla K H Mayer H Kishi E Gilleece M Syvanen J D Hopkins 《Science (New York, N.Y.)》1985,230(4721):87-88
Bacteria of different genera isolated at nine medical centers in different parts of the United States and at one center in Venezuela during the first decade of gentamicin usage carried the gentamicin resistance gene 2"-aminoglycoside nucleotidyltransferase on the same transferable plasmid. Such widespread dissemination of a newly observed resistance gene on one plasmid suggests that a new resistance gene may emerge once on a single plasmid, which then carries it to other centers and other plasmids. The resistance gene might, therefore, be contained if detected early. 相似文献
24.
Hiroaki Kawamura 《Agriculture and Human Values》2004,21(2-3):157-169
Indigenous ecologies in industrial societies need immediate attention in light of the ongoing debate on indigenous resource rights and decreasing biodiversity. This paper examines the functions and meanings of hunting, fishing, and gathering activities among contemporary Nez Perce Indians in Idaho, USA. The collected data were analyzed with Pierre Bourdieu's (1977) concepts of “symbolic capital” and “practice” within the framework of political ecology. The results clearly demonstrate that hunting, fishing, and gathering practices play significant roles not only in social and religious but also economic and political senses within the contemporary Nez Perce society. This study suggests that investigation of indigenous ecologies in industrial societies take a synthesized approach between idealist and materialist perspectives. 相似文献
25.
Hu J Zhong C Ding C Chi Q Walz A Mombaerts P Matsunami H Luo M 《Science (New York, N.Y.)》2007,317(5840):953-957
Carbon dioxide (CO2) is an important environmental cue for many organisms but is odorless to humans. It remains unclear whether the mammalian olfactory system can detect CO2 at concentrations around the average atmospheric level (0.038%). We demonstrated the expression of carbonic anhydrase type II (CAII), an enzyme that catabolizes CO2, in a subset of mouse olfactory neurons that express guanylyl cyclase D (GC-D+ neurons) and project axons to necklace glomeruli in the olfactory bulb. Exposure to CO2 activated these GC-D+ neurons, and exposure of a mouse to CO2 activated bulbar neurons associated with necklace glomeruli. Behavioral tests revealed CO2 detection thresholds of approximately 0.066%, and this sensitive CO2 detection required CAII activity. We conclude that mice detect CO2 at near-atmospheric concentrations through the olfactory subsystem of GC-D+ neurons. 相似文献
26.
Kumagai H Miyakawa K Negishi H Inoue H Obara K Suetsugu D 《Science (New York, N.Y.)》2003,299(5615):2058-2061
Very-long-period (VLP) signals showing simple decaying harmonic oscillations with periods near 10 seconds and lasting for about 300 seconds were observed in association with an earthquake swarm that occurred beneath Hachijo Island, Japan. Results from the source-mechanism analysis and waveform simulation based on a fluid-filled crack model consistently point to the resonance of a dike filled with a basaltic magma as the source of the VLP signals. Thus, VLP signals can be used to probe the state of the fluid and dynamic processes within a volcanic system. 相似文献
27.
An isotope dilution method using [1‐13C]sodium acetate was applied to determine the effect of feeding ensiled hop (Humulus lupulus L.) residues on plasma acetate turnover rate in six adult crossbred sheep. The sheep were fed 63 g/kg body weight (BW)0.75/day of either mixed hay of orchardgrass (Dactylis glomerata L.) and reed canarygrass (Phalaris arundinacea L.) and round bale silage at 3:1 ratio (Hay‐diet), or another where round bale silage was replaced by ensiled hop residues (Hop‐diet) with a crossover design each of a 3‐week period. The isotope dilution method was performed on day 21 of each dietary treatment. Dry matter digestibility was similar between diets, and nitrogen (N) digestibility was lower (P = 0.001) for Hop‐diet than Hay‐diet. However, N retention did not differ between diets. Plasma acetate concentration was lower (P = 0.04) for Hop‐diet than Hay‐diet, and the turnover rate of plasma acetate did not differ between diets. Plasma concentration of lactate and non‐esterified fatty acids were similar between diets. Hop‐diet was found almost comparable to Hay‐diet on plasma acetate turnover rate in the present experimental conditions. Therefore, it could be concluded that hop residues partially could be used as an alternative to traditionally used round bale silage for rearing sheep. 相似文献
28.
Xie Weimin Wang Qunhui Yao Jie Ma Hongzhi Ohsumi Yukihide Ogawa Hiroaki I. 《Water, air, and soil pollution》2004,159(1):313-324
The adsorption of a fixed bed filled with bone char was investigated in terms of its efficiency and capacity by determining operational conditions for the purpose of further reduction of organic matter and removal of phosphorus using a continuous flow of real secondary effluent. Simultaneous removals of phosphorus and chemical oxygen demand (COD) were sufficiently achieved by this fixed-bed method. Stable performance was maintained even at a linear flow velocity (abbreviated as LV) of 1.5 m h–1. Appropriate backwashing and regeneration were required to operate the system continuously for a long period of time. During the regeneration, the use of treated water including Ca2+ ion was so effective that phosphorus removal efficiency increased from about 50 to 80%, and afterwards maintained over 65%, until inflow water of the volume up to 150 times as large as the volume of bone char had passed through. Even when the inflow water of the volume rose up to 200 times, the phosphorus removal efficiency could be maintained over 50%. During this operation, the adsorptions of phosphorus and COD onto the bone char surface were observed to be over 6.7 and 35 gL–1, respectively. 相似文献
29.
Adsorption behavior of heavy metals on biomaterials 总被引:8,自引:0,他引:8
Minamisawa M Minamisawa H Yoshida S Takai N 《Journal of agricultural and food chemistry》2004,52(18):5606-5611
We have investigated adsorption of Cd(II) and Pb(II) at pH 2-6.7 onto the biomaterials chitosan, coffee, green tea, tea, yuzu, aloe, and Japanese coarse tea, and onto the inorganic adsorbents, activated carbon and zeolite. High adsorptive capabilities were observed for all of the biomaterials at pH 4 and 6.7. In the adsorption of Cd(II), blend coffee, tea, green tea, and coarse tea have comparable loading capacities to activated carbon and zeolite. Although activated carbon, zeolite, and chitosan are utilized in a variety of fields such as wastewater treatment, chemical and metallurgical engineering, and analytical chemistry, these adsorbents are costly. On the other hand, processing of the test biomaterials was inexpensive, and all the biomaterials except for chitosan were able to adsorb large amounts of Pb(II) and Cd(II) ions after a convenient pretreatment of washing with water followed by drying. The high adsorption capability of the biomaterials prepared from plant materials is promising in the development of a novel, low-cost adsorbent. From these results, it is concluded that heavy metal removal using biomaterials would be an effective method for the economic treatment of wastewater. The proposed adsorption method was applied to the determination of amounts of Cd(II) and Pb(II) in water samples. 相似文献
30.
Hiroaki Iwaisaki 《Livestock Production Science》1983,10(6):611-616
The data on classified type-characteristics of 1692 Japanese Black breeding heifers were analyzed to investigate the effects of discontinuity and to estimate the heritabilities and phenotypic correlations in the underlying continuous scale. The parameters in an outward scale were computed with the equally-spaced scoring, employing mixed-model least squares procedures, and then those were adjusted for the effects of discontinuity.The effects of discontinuity for the classified type characteristics were generally minor in this applied work. 相似文献