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131.
132.
Experiments were conducted for the use of prostaglandin to synchronise oestrus in dairy cows. One single dose of 5 mg F2-Alpha prostaglandin was administered via the intrauterine route. The reference values of the control groups were matched by first insemination following induced oestrus among the best of the test animals which were inseminated twice. These values reached 72 and 96 hours following application accounted for 46.7 and 50.0 per cent. The yellow body phase, a prerequisite for oestrus production by prostaglandins, had been induced in the test animals by cycle blocking, using gestagen. Possible use of the method in a bio-engineering context for large-scale oestrus synchronisation in cows is discussed.  相似文献   
133.
The relative importance of the depletion of ergosterol versus the accumulation of precursor or abnormal sterols in the mechanism of fungal growth inhibition by sterol biosynthesis inhibitor fungicides is incompletely understood. In order to investigate this problem further, the degree of inhibition of the growth of Nectria haematococca by fungicides with different enzymatic targets in the sterol biosynthetic pathway was determined and compared with their effects on the sterol profile. The sensitivity of N. haematococca was highest towards fenpropimorph, followed by tebuconazole, terbinafine, fenpropidin and tridemorph. Terbinafine, a squalene epoxidase inhibitor, induced a very large accumulation of squalene without very significant inhibition of ergosterol biosynthesis and growth. The fungus appeared able to tolerate large amounts of squalene. In the case of tebuconazole, a sterol 14α-demethylase inhibitor, it seemed that the accumulation of C4 mono- and dimethyl sterols was responsible for fungitoxicity. Fenpropimorph and fenpropidin seemed to be good inhibitors of both sterol Δ14-reductase and Δ8→Δ7-isomerase, whereas tridemorph was a better inhibitor of Δ8→Δ7-isomerase than of the Δ14-reductase. Large accumulations of Δ8,14- or Δ8-sterols and correspondingly large decreases in the ergosterol content are both implicated in the fungitoxicity of these compounds in N. haematococca. © 1998 Society of Chemical Industry  相似文献   
134.
135.
Journal of Soils and Sediments - The aims of the current study were to (1) examine the interactive effects of biochar addition and differently textured soils (clayey and sandy soils) on nutrient...  相似文献   
136.
The aim of the present study was to investigate the relationship between the metabolite profile of milk and important technological properties by using nuclear magnetic resonance (NMR)-based metabolomics. The metabolomics approach was introduced for the metabolic profiling of a set of milk samples from two dairy breeds representing a wide span in coagulation properties. The milk metabolite profiles obtained by proton and carbon NMR spectroscopy could be correlated to breed and, more interestingly, also with the coagulation profile, as established by traditional methods by using principal component analysis (PCA). The metabolites responsible for the separation into breed could mainly be ascribed to carnitine and lactose, whereas the metabolites varying in the samples with respect to coagulation properties included citrate, choline, carnitine, and lactose. The results found in the present study demonstrated a promising potential of NMR-based metabolomics for a rapid analysis and classification of milk samples, both of which are useful for the dairy industry.  相似文献   
137.
杀菌剂生物测定技术的发展   总被引:1,自引:0,他引:1  
概述了杀菌剂生物测定的发展历史,探讨了离体、活体和组织筛选的常规生物测定技术,以及高通量筛选方法,同时从多个角度阐述了杀菌剂生物测定技术的发展趋势。  相似文献   
138.
Nine fungicides that inhibit ergosterol biosynthesis (diclobutrazol, fenarimol, fenpropimorph, imazalil, nuarimol, prochloraz, propiconazole, triadimefon, triadimenol) and one plant growth regulator (ancymidol) were administered to Japanese quails (Coturnix coturnix). Most of these compounds had a moderate or no effect, but prochloraz, imazalil and, to a lesser extent, propiconazole were shown to produce a dramatic increase in liver weight and cytochrome P-450 level. These three compounds were also found to be potent in-vitro inhibitors of 7-ethoxycoumarin O-de-ethylase and aniline hydroxylase, thus resulting in a biphasic effect on drug-metabolising enzymes. With these three compounds, and some others, an accumulation of lanosterol in liver was also observed, suggesting an inhibition of sterol synthesis.  相似文献   
139.
Fenhexamid, a recently developed botryticide, is shown here to inhibit sterol biosynthesis. When the fungus Botryotinia fuckeliana was grown in the presence of fenhexamid, the ergosterol content was reduced, and three 3‐keto compounds, 4α‐methylfecosterone, fecosterone and episterone, accumulated, suggesting an inhibition of the 3‐keto reductase involved in C‐4 demethylation. Thus, fenhexamid belongs to a new, promising class of sterol biosynthesis inhibitors not previously used in agriculture or in medicine. © 2001 Society of Chemical Industry  相似文献   
140.
Leachable chromium in the incineration fly ash and wastewater sludge has been thermally stabilized by plasma melting at the temperature of 1,773?K. To better understand how chromium is stabilized with the high-temperature treatment, chemical structure of the slags sampled at temperature zones of 1,100?C1,700?K has been studied by synchrotron X-ray absorption spectroscopy. The component-fitted X-ray absorption near edge structure spectra of chromium indicate that the main chromium compounds in the sludge and fly ash are Cr(OH)3, Cr2O3, and CrCl3. A small amount of toxic CrO3 is also observed in the fly ash. In the plasma melting chamber under the reducing environment, the high-oxidation state chromium is not found. The slags in the plasma melting chamber have much less leachable chromium, which is due to chemical interactions between chromium and SiO2 in the slags. The existence of the interconnected Cr-O-Si species is observed by refined extended X-ray absorption fine structure spectroscopy. In the Cr2O3 phase of the slags, their bond distances, and coordination numbers for the first (Cr-O) and second (Cr-(O)-Cr) shells have insignificant perturbation when experienced with different melting temperatures between 1,300 and 1,700?K. It seems that Cr2O3 and chromium encapsulated in the silicate matrix of the slags have relatively much lower leachability. With this concept, to obtain a low chromium leachability slag from the plasma melting process, the residence time of the melting chamber may be decreased, and the slag discharge temperatures may be increased to 1,300?K. This work also exemplifies utilization of molecule-scale data obtained from synchrotron X-ray absorption spectroscopy to reveal how chromium is thermally stabilized in a commercial scale plasma melting process.  相似文献   
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