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31.
Assessment of the water quality of two rivers in Hanoi City and its suitability for irrigation water
Nguyen Thi Lan Huong Masami Ohtsubo Loretta Li Takahiro Higashi Motohei Kanayama 《Paddy and Water Environment》2008,6(3):257-262
The To Lich and Kim Nguu Rivers in Hanoi City are the main sources of irrigation water for suburban agricultural land and
fish farm. Wastewater from the industrial plants located along these rivers has been discharged, and has degraded the water
quality of the rivers. This study describes the chemical properties of water from the rivers, focusing on heavy metal pollution
and the suitability of water quality for irrigation water. Water from the rivers was heavily polluted with organic matter
and heavy metals such as Pb, Cu, Zn, Cr, Cd and Ni. Dissolved oxygen, chemical oxygen deman, and total suspended solids, and
the concentrations of all heavy metals exceeded the Vietnamese standard for surface water quality in all investigated sites.
The concentrations of some heavy metals such as Cu, Cd, Cr and Ni were above the internationally recommended WHO maximum level
for irrigation water. A wide variation in the heavy metal concentration of water due to metal types is the result of wastewater
discharged from different industrial sources. 相似文献
32.
Yaguang Zhou Masami Fushitani Keiichi Sato Masayuki Ozawa 《Journal of Wood Science》2000,46(6):423-430
This study examined the bending creep behavior of hot-pressed wood during cyclic moisture changes. Sugi (Cryptomerica japonica D. Don) specimens were pressed in the radial direction under six combinations of nominal compressive strain (33% and 50%) and press temperatures (140°C, 170°C, 200°C). Creep tests were conducted at 20°C with three cyclic relative humidity changes between 65% and 95% under 25% of short-breaking stress. The effect of moisture content (MC) change on elastic compliance and mechanosorptive (MS) compliance was investigated. The relation between MS compliance and thickness swelling was studied. The results indicated that total compliance increased over the history of cyclic moisture changes; and its behavior was closely related to the changes in MC and thickness swelling. The total compliance increased during adsorption and decreased during desorption. Elastic compliance increased linearly with MC and was dependent on press temperature and compression. With increasing MC change, MS compliance increased during adsorption and decreased during desorption. The first adsorption led to greater MS compliance than did the subsequent adsorption with the same amount of MC change. In general, the elastic parameterK
E and the MS parameterK
Mincreased with compression and decreased as the press temperature increased. The MS parameterK
M was apparently greater than the elastic parameterK
E. The MS parameterK
M increased with swelling coefficient KSW of the hot-pressed specimen during adsorption and decreased with an increasing shrinkage coefficientK
SH during desorption. 相似文献
33.
Uechi M Hori Y Fujimoto K Ebisawa T Yamano S Maekawa S 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2006,68(6):549-553
The aim of this study was to determine whether dobutamine, dopamine, or milrinone (a phosphodiesterase [PDE] III inhibitor) would support cardiac function that had been attenuated by administration of the beta-blocker, carvedilol (0.2, 0.4, or 0.8 mg/kg). Hemodynamic and cardiac parameters including the heart rate (HR), left-ventricular fractional shortening (FS), and arterial pressure were measured in six healthy dogs without cardiac disease. Carvedilol did not affect FS or arterial pressure, but decreased the HR significantly. The positive inotropic and chronotropic responses to dobutamine and dopamine were attenuated by carvedilol, whereas arterial pressure was unaffected. Milrinone did not affect the HR and decreased arterial pressure, whereas FS was significantly greater both in the control and carvedilol-treated groups. Although milrinone affect the negative chronotropic effects of carvedilol, milrinone increased FS and prevented the decrease in arterial pressure. These results suggest that inhibition of PDE III preserves cardiac contractility and hemodynamic function in the presence of carvedilol. 相似文献
34.
Hori Y Takusagawa F Ikadai H Uechi M Hoshi F Higuchi S 《American journal of veterinary research》2007,68(10):1058-1063
OBJECTIVE: To investigate the diuretic effects, tolerability, and adverse effects of furosemide and torsemide after short- and long-term administration in healthy dogs. ANIMALS: 8 mixed-breed dogs. PROCEDURES: In a crossover study, furosemide (2 mg/kg), torsemide (0.2 mg/kg), or placebo (bifidobacterium [1 mg/kg]) was administered orally to each dog every 12 hours for 14 days. Blood and urine samples were collected before the study (baseline data) and at intervals on the 1st (short-term administration) and 14th day (long-term administration) of treatment for assessment of urine volume and specific gravity and selected clinicopathologic variables including BUN, creatinine, and aldosterone concentrations, and creatinine clearance. RESULTS: Compared with the baseline value, short-term administration of furosemide or torsemide immediately increased urine volume significantly; after long-term administration of either drug, urine specific gravity decreased significantly. Compared with the effect of placebo, the 24-hour urine volume was significantly increased after short-term administra-tion of furosemide or torsemide. In addition, it was significantly increased after long-term administration of torsemide, compared with that of short-term administration. Long-term administration of furosemide or torsemide increased the BUN and plasma creatinine con-centrations, compared with the baseline value. Compared with the baseline value, plasma aldosterone concentration was significantly increased after long-term administration of either drug and was significantly higher after torsemide treatment than after furosemide treatment. CONCLUSIONS AND CLINICAL RELEVANCE: In dogs, diuretic resistance developed after 14 days of furosemide, but not torsemide, administration; however, both loop diuretics were associated with increased BUN and plasma creatinine concentrations, compared with values before treatment. 相似文献
35.
Nobutaka Someya Shinichi Numata Masami Nakajima Akira Hasebe Katsumi Akutsu 《Journal of General Plant Pathology》2004,70(6):371-375
Chitinolytic activity of the biocontrol bacterium Serratia marcescens strain B2 was inhibited by bacteria isolated from rice, even though its growth was not affected. Antifungal activity of the strain against Pyricularia oryzae was also reduced under the influence of these bacteria. In contrast, the rice-epiphytic bacterium Erwinia ananas NR1, transformed with chitinase gene chiA derived from strain B2, had high chitinolytic activity regardless of the presence of the bacteria isolated from rice. Therefore, the introduction of an antagonistic factor gene with a promoter from the recipient into the epiphytic bacteria may prove useful in the development of effective biocontrol agents. 相似文献
36.
Nobutaka?Someya Masami?Nakajima Ken?Watanabe Tadaaki?Hibi Katsumi?AkutsuEmail author 《Journal of General Plant Pathology》2003,69(5):342-347
Serratia marcescens strain B2 is an antagonistic bacterium that produces the red-pigmented antibiotic prodigiosin and suppresses rice sheath blight caused by Rhizoctonia solani AG-1 IA. Rice sheath blight disease was suppressed when plants were inoculated with this bacterium an hour before pathogen inoculation but not when plants were treated 4 weeks before pathogen inoculation. In both cases the bacteria were detected in the rice rhizosphere 4 weeks after inoculation. Bacteria isolated from the rice plant and rhizosphere inhibited biosynthesis of prodigiosin in S. marcescens strain B2. We suggest that bacteria isolated from rice plants and rhizospheres mediate the suppression of antibiotic production of biological control agents and that such suppression is common under field conditions. 相似文献
37.
Progesterone stimulation by LH involves the phospholipase-C pathway in bovine luteal cells 总被引:2,自引:0,他引:2
Nishimura R Shibaya M Skarzynski DJ Okuda K 《The Journal of reproduction and development》2004,50(2):257-261
Luteinizing hormone (LH)-stimulated steroidogenesis in luteal cells is known to be mediated through the activation of cyclic AMP (cAMP)-dependent protein kinase, and to be also modulated by calcium-dependent mechanisms. In the present study, we tested the hypothesis that LH stimulates progesterone (P4) production in bovine luteal cells through activation of phospholipase (PL) C by using a cell culture system. Bovine mid-luteal cells (Days 8-12 of the estrous cycle) were cultured for 24 h and then exposed to a PLC inhibitor (U-73122; 10 microM) with or without LH (10 ng/ml) for 4 h. U-73122 blocked LH-stimulated P4 production without affecting cAMP accumulation. Moreover, exposure of luteal cells to PLC increased P4 production in a dose-dependent manner. These results support the hypothesis that the luteotropic action of LH in bovine luteal cells is mediated not only by activation of adenylate cyclase but also by activation of PLC. 相似文献
38.
Caulogenic calli with a high differentiation potency were induced from mature embryos ofPicea jezoensis seeds stored over a long time, for 29 years, resulting in the active formation of adventitious buds. Embryos began to induce
calli within 3 weeks of cultivating on LP medium containing 3 μM BAP and 1 μM 2,4-D. Then, the calli proliferated and transformed
into caulogenic calli with bud primordia in 8 weeks. The caulogenic calli increased actively with the addition of 500 mg/l ofl-glutamine in the medium. Furthermore, caulogenic calli, induced on LP medium containingl-glutamine, resulted in the formation of adventitious buds, which elongated after transferring the calli into LP medium with
0.1 μM BAP, but withoutl-glutamine. It appears that the number of adventitious buds and the process of shoot elongation are influenced by the kind
of nitrogen contained in the medium for callus induction.
A part of this study was presented at the 107th Annual Meeting of the Japanese Forestry Society (1996). 相似文献
39.
Akiko Nagasaka Yu Nagasaka Kinuko Ito Tsutomu Mano Masami Yamanaka Atushi Katayama Yoshikazu Sato Andrey L. Grankin Andrey I. Zdorikov Gennady A. Boronov 《Journal of Forest Research》2006,11(5):377-382
We examined the relationship between the annual escapement of salmon and the δ
15N of willow (Salix spp.) leaves to evaluate the contribution of marine-derived nutrients (MDN) to riparian vegetation around the Pacific Northwest
and Northeast regions. Foliar δ
15N values ranged from −3.42‰ to 4.65‰. The value increased with increasing density of carcasses up to 500 fish/km and 1500
fish/km. δ
15N values were variable at carcass densities below 500 fish/km. Possible factors affecting the fluctuation of δ
15N at reference sites are: (1) denitrification; (2) the presence of N2-fixing trees, such as alder; and (3) agricultural runoff. δ
15N values at the sites with carcass densities over 500 fish/km were consistently high, while a value of δ
15N below zero was observed at only one site (Rusha River; δ
15N = −1.87‰). At this site, most adult pink salmon returned to limited locations near the estuary because steeper channel gradients
acted as a migration barrier, resulting in the negative δ
15N value. Nevertheless, we concluded that our results showed evidence of the feedback of MDN to terrestrial vegetation, although
the use of the δ
15N value as a terrestrial end member at spawning sites is limited. If the relationship between the enrichment index, which
is expressed as the values using a mixing model, and salmon abundance was estimated, the availability of MDN in riparian ecosystems
could possibly be evaluated and will lead to the establishment of escapement goals.
An erratum to this article is available at . 相似文献
40.
Ebisawa T Uechi M Hori Y Yamano S 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2006,68(12):1355-1357
The aim of the present study was to evaluate short term urinary NAG levels in a model of reduced kidney mass. The half and quarter kidney mass were made from ligation of the renal artery. Both groups decreased in the level of excreted NAG on day 1 and 2 after operation. On day 5 after operation, both groups achieved urinary enzyme levels comparable to that of the sham-operated group. The remaining compensated nephrons held normal range of excreted urinary NAG levels, although reduced number of nephrons resulted in a decline in urinary NAG levels. 相似文献