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241.
242.
Recent studies have indicated that dogs with canine atopic dermatitis (CAD) may have a disorder of fatty acid metabolism: possibly low or absent activity of delta6-desaturase or delta5-desaturase, or both. To clarify this possibility, we examined the erythrocyte and plasma fatty acid patterns of 8 dogs with CAD and their 8 healthy housemates. Atopic dermatitis was diagnosed according to the criteria proposed by Willemse; other causes of dermatitis were excluded clinically and by appropriate tests. Erythrocyte ghosts were prepared from blood samples. Membrane lipids were extracted and separated by thin-layer chromatography. From plasma and lipid fractions, fatty acid content was determined by gas chromatography. In erythrocytes, but not in plasma, we observed significant differences in the fatty acid pattern that suggested a reduction in the n6 fatty acid products of the delta6- and delta5-desaturases in dogs with atopic dermatitis when compared with healthy housemates.  相似文献   
243.
Inhibition of carotenoid biosynthesis by herbicidal m-phenoxybenzamide derivatives has been investigated in a cell-free carotenogenic system from Aphanocapsa. Their target is the phytoenedesaturase reaction. Double-reciprocal plots of β-carotene biosynthesis (from 14C-labeled geranylgeranyl pyrophosphate) showed that 3-(2,5-dimethylphenoxy)-N-ethylbenzamide was a noncompetitive inhibitor of the phytoene-desaturase complex. The Ki value for cell-free inhibition of β-carotene formation was almost identical to the I50 value of intact cells. Furthermore, the influence of certain substituents on herbicidal activity has been investigated. Inhibition increased with the length of the unbranched N-alkyl chains. In addition, substituents at the phenoxy group with higher lipophilicities showed greater inhibitory activities. The presence of a phenoxy or trifluoromethyl moiety at position 3 is essential.  相似文献   
244.
The competitive ability of maize is low in its early growth stages and because of this weed control is essential. Agricultural practice is dominated by chemical weed control. The trials indicated that some herbicide mixtures used at 75% of the permitted dose have herbicidal potential. In trials in the states Brandenburg, Sachsen, Sachsen-Anhalt and Thüringen, four herbicide mixtures were tested in the years 2004 to 2006.The practiced 75% of permitted dose and 50% of permitted doses were tested for their herbicidal potential. The weed species react differently to reduced herbicide doses. 50% of the 26 recorded weed species showed no drop in herbicide treatment efficacy at a reduced dose compared to the recommended dose. A drop in efficacy of between 1 and 5% was recorded after use of reduced herbicide rates in 25% of the other recorded weed species. 15?% of all recorded weed species showed a drop of efficacy of between 5 to 10%. Only 10% of recorded weed species reacted with an efficacy drop of more than 10?% between recommended and reduced doses. The tested herbicide mixtures had a different herbicidal potential for specific weed species. The herbicide treatment in maize is carried out after emergence of the weed species. It is therefore possible to choose the most suitable herbicide mixture at the 50% dose rate with the smallest drop of efficacy to target the specific species. In this way only slightly more weeds survive at a higher density compared with the recommended dose rate. The selection pressure is hardly higher. The knowledge of the herbicidal potential of mixtures could be used in agricultural practice. In this way the input of active ingredient/area can be reduced by the approximate efficacy of herbicide treatments. The tested herbicide mixtures are only an example of how, by the knowledge of efficacy reserves of herbicide in relation to the weeds present, the applied dose can be better adapted to the treatment frequency index.  相似文献   
245.
Ethephon application on four dates did not induce budset in slash and loblolly pine seedlings. Ethephon promoted slash pine budbreak by 11 days when applied in mid-November and delayed loblolly pine budbreak by 8 days when applied in late November. Mid-November and early February applications of ethephon promoted height growth of both species.  相似文献   
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Zusammenfassung In Versuchen, die bis zu 21 Wochen dauerten, wurde mit Toxaphen und Endrin behandeltes Gras, das teilweise in siebentägigem Abstand gespritzt worden war, an Kaninchen verfüttert. Die Tiere befanden sich z. T. während der Dauer des ganzen Versuches ständig auf den mit den Präparaten behandelten Parzellen. Neben einer anfänglichen Gewichtsabnahme, die aber durch den Übergang von der Stallhaltung zur Freilandhaltung bedingt war, konnte bei allen Tieren keine auffallende Veränderung festgestellt werden.Die Repellentwirkung der Wirkstoffe Toxaphen und Endrin bestätigte sich immer dann, wenn den Kaninchen zum erstenmal behandeltes Futter vorgelegt wurde, das nur zögernd angenommen wurde.Eine achtfache Überkonzentration von Toxaphen und Endrin verursachte bei Toxaphen nur Fieber des Tieres und bei Endrin typische Vergiftungserscheinungen, die aber nach vier Tagen durch Verabreichung von unbehandeltem Futter wieder behoben waren.Durch die ständige Fütterung von behandeltem Gras wurde die Fertilität der Kaninchen beeinflußt. Keine der Häsinnen wurde trächtig.Zur Beurteilung der Giftigkeit eines Pflanzenschutzmittels dürfen die in der Natur auftretenden Krankheiten nicht übersehen werden. In unseren Versuchen gingen drei Kaninchen von den Toxaphenparzellen ein. Mit Sicherheit konnte Coccidiose bei zwei Tieren als Todesursache nachgewiesen werden.Untersuchungen, ob das Blutbild durch Toxaphen und Endrin quantitativ verändert wird, verliefen negativ.Versuche mit weißen Mäusen ergaben, daß das Blutbild keine Veränderung erfährt, daß aber wie bei den Kaninchen Fertilitätsstörungen auftreten. Die Vitalität der Jungen war bei Endrin geringer als bei Toxaphen.Eine Gewöhnung der Mäuse an Toxaphen und Endrin ist vorhanden.
Summary In experiments which lasted up to 21 weeks, grass prepared with Toxaphen and Endrin, which partly had been squirted in intervals of seven days, was given as feeding to rabbits. During the whole time of the experiment the animals steadily have been on the lots prepared with those preparations. Beside of an initial loss in weight which was, however, caused by the change from keeping them caged to keeping them in field, one could not state a striking change among all animals.The repellency of the substances Toxaphen and Endrin was always confirmed then, when prepared food was given to the rabbits for the first time, which was only hesitatingly accepted by them. An eightfold overconcentration of Toxaphen and Endrin — concerning Toxaphen caused only fever of the animals, concerning Endrin typical symptoms of poisoning which, however, were removed after 4 days by giving unprepared food.In the consequence of the permanent feeding of prepared grass the fertility of the rabbits was affected. No one of the female became pregnant.Judging the toxic effect of a plant-protection-preparation the illnesses being in nature should not be overlook. During our trials three of twelve rabbits died on the Toxaphen lots. It is guaranteed, that two of these treated animals died of Coccidiose.Researches, whether the blood was quantitatively changed by Toxaphen and Endrin took a negative course.Experiments by means of white mice showed, that the blood is not affected by a change, that however, there appear fertility-disturbances as with the rabbits. The vitality of the young ones has been diminished more by using Endrin than using Toxaphen.An accustoming of the mice to Toxaphen and Endrin is existing.
  相似文献   
248.
249.
Four great tits (Parus major) with nodular lesions suggestive of poxvirus infections were observed in a garden in Vienna, Austria. One of the birds was submitted for examination. Because of its poor condition, the bird had to be euthanatized and was subsequently necropsied. An avipoxvirus infection was confirmed by histopathology, electron microscopy, and polymerase chain reaction and sequencing. This is the second report of naturally occurring poxvirus infection in great tits and the first of its kind in central Europe.  相似文献   
250.
This paper documents the medicinal plants used to treat endoparasites and stomach problems in dogs, cats and pigs in British Columbia, Canada. Ethnoveterinary data was collected over a 6-month period in 2003. The majority of the information on pets came from 2 naturopaths, 10 herbalists, 5 dog trainers, breeders and pet shop owners, 9 holistic veterinarians and 6 of 27 organic farmers. Two pig farmers joined the study in the final stages. The following plants were used as anthelmintics: Artemisia cina O. Berg and C.F. Schmidt, Artemisia vulgaris L., Artemisia annua, Calendula officinalis L., Echinacea purpurea (L.) Moench (all Asteraceae), Mentha piperita L. and Salvia officinalis L. (Lamiaceae) (Allium sativum L. (Alliaceae), Cucurbita pepo L. (Cucurbitaceae), Eugenia caryophyllata Thunb (Myrtaceae), Gentiana lutea L. (Gentianaceae), Hydrastis canadensis L. (Ranunculaceae), Juglans nigra L. (Juglandaceae), Olea europaea L. (Oleaceae) and Ruta graveolens L. (Rutaceae)). Stomach problems were treated with: Achillea millefolium L. (Asteraceae), Aloe vera (L.) Burm. f. (Asphodelaceae), Elytrigia repens (L.) Desv. ex Nevski (Poaceae), Frangula purshiana (DC.) Cooper (Rhamnaceae), Juniperus communis L. (Cupressaceae), Melissa officinalis L. and M. piperita L. (Lamiaceae), Petroselinum crispum L. (Apiaceae), Plantago major L. and Plantago ovata Forssk. (Plantaginaceae) Rumex crispus L. and Rumex obtusifolius L. (Polygonaceae), Ulmus fulva Michx. (Ulmaceae) and Zingiber officinalis Roscoe (Zingiberaceae). There is insufficient information available to assess the anthelmintic efficacies of C. officinalis, Salvia officinalis, Eugenia caryophyllata and O. europaea; the other plants have mid- to high-level validity for their ethnoveterinary uses.  相似文献   
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