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111.
In veterinary patients, postgastric feeding is indicated for uncontrollable gastric vomiting, gastroparesis, biliary tract disease, pancreatitis, and for patients at increased risk for aspirating secondary to decreased mentation, prolonged recumbency, or an unprotected airway. Postgastric feeding may be implemented via the placement of a jejunal feeding tube. These tubes can be placed surgically (jejunostomy tubes) or with fluoroscopic or endoscopic guidance. This article will focus on methods of jejunal feeding-tube placement, advantages and disadvantages of the methods described, and complications associated with jejunal feeding.  相似文献   
112.
Paddy and Water Environment - Drainage is a profitable water management operation in waterlogged soils, particularly in hot, arid environments where waterlogging is caused by irrigation and salts...  相似文献   
113.
The principal neutral carbohydrate of three samples of echidna milk was identified as a trisaccharide, fucosyllactose. That of a sample of platypus milk was a tetrasaccharide, difucosyllactose. Free lactose was found in small amounts only. The milk carbohydrate of monotremes is distinguished from that of both marsupials and placental mammals by its high fucose content.  相似文献   
114.
Sir:- Benzimidazole (Bz) resistant Nematodirus spathiger were first recorded in New Zealand in 1983.(2)  相似文献   
115.
Oxfendazole (5 mg/kg) was tested against natural infections of nematodes and cestodes in sheep in three experiments.

It was 100% effective against all stages of Ostertagia sp., Nematodirus spathiger, Oesophagostomum venulosum, Chabertia ovina, Moniezia expansa, immature 5th stage and adult Cooperia curticei and 4th stage Trichostrongylus sp. Efficacy was 99%–100% against immature 5th stage and adult Trichostrongylus sp., 67.8%and 91.6% against adult Strongyloides sp., 80.7%and 89.5% against immature 5th stage Trichuris ovis and 74% and 79% against Trichuris ovis.  相似文献   
116.
This review is intended to provide plant pathologists and other scientists with a current overview of the most important Fusarium phytopathogens and mycotoxin producers. Knowledge of Fusarium species diversity and their evolutionary relationships has increased dramatically due to the application of multilocus molecular phylogenetics and genealogical concordance phylogenetic species recognition over the past 15 years. Currently Fusarium is estimated to comprise at least 300 genealogically exclusive phylogenetic species; however, fewer than half have been formally described. The most important plant pathogens reside in the following four groups: the F. fujikuroi species complex noted for Bakanae of rice, ear rot of maize, pitch canker of pine and several species that contaminate corn and other cereals with fumonisin mycotoxins; the F. graminearum species complex including the primary agents causing Fusarium head blight of wheat and barley that contaminate grain with trichothecene mycotoxins; the F. oxysporum species complex including vascular wilt agents of over 100 agronomically important crops; and the F. solani species complex, which includes many economically destructive foot and root rot pathogens of diverse hosts. Several other Fusarium phytopathogens reported from Japan and nested within other species complexes are reviewed briefly. With the abandonment of dual nomenclature, a broad consensus within the global community of Fusarium researchers has strongly supported the unitary use of the name Fusarium instead of several teleomorph names linked to it. Plant pathologists and other scientists needing accurate identifications of Fusarium isolates are encouraged to use Fusarium-ID and Fusarium MLST, Internet accessible websites dedicated to the molecular identification of Fusarium species.  相似文献   
117.
The key to achieving effective weed control is to target them when they are young. Understanding their temperature and moisture requirements for emergence will help growers to develop timely control strategies. This study examined the emergence requirements of four key species: Conyza bonariensis, Sonchus oleraceus, Echinochloa colona and Chloris virgata. Two experiments were conducted in a growth room with temperatures of 25/15 and 30/20°C day/night with a photoperiod of 12 h. The first experiment examined emergence under single rainfall events of 0, 2, 5, 10, 20, 30 and 50 mm. The second experiment examined emergence under accumulated rainfall events of 0 mm, 5 mm × 2 (consecutive) days, 5 mm × 4 days, 5 mm × 6 days, 10 mm × 1 day, 10 mm × 2 days and 10 mm × 3 days. The temperature was not significant on emergence in both experiments. In the first experiment, at least 10 mm of rainfall was required for the emergence of all the species, with significantly higher germination rates at rainfall amounts of >20 mm. In the second experiment, the species had higher emergence rates with accumulated rainfall over consecutive days, rather than single rainfall events of the same amount. The length of time that the soil surface remained above the permanent wilting point, allowing the imbibition of water, was also an important factor. This study has provided information on the drivers for emergence of these species and will assist growers in determining what rainfall events are likely to trigger emergence in the field and make timely weed management decisions.  相似文献   
118.
Ecosystem services: Classification for valuation   总被引:4,自引:0,他引:4  
This letter is in response to an article by Ken Wallace titled “Classifications of ecosystem services: problems and solutions” (Biological Conservation 139, 2007). This letter discusses the points we see as problematic with Wallace’s framework and sets out our conceptualization of linking ecosystem services with human welfare. In this letter we suggest that utilizing the terms intermediate services, final services and benefits should go a long way to clearing up much of the ambiguity in ecosystem services typologies, especially for economic valuation purposes. As Wallace points out, clearly defining and organizing the concept of ecosystem services is not just a semantic decision, but it is integral to operationalizing something that can clearly illuminate tradeoffs in natural resource management.  相似文献   
119.
Two Friesian cows were used to attempt to produce colostrum containing a high concentration of clostridial antibodies which could be fed to newborn lambs in order to passively transfer immunity to diseases caused by clostridia. One cow was given a commercial multicomponent clostridial sheep vaccine in two successive pregnancies and the second cow in one pregnancy. The first cow produced a low concentration of epsilon antitoxin (Clostridium perfringens, type D) in its blood and colostrum after the first course of three injections of vaccine. A higher concentration was produced by cow 2 after a course of six injections and by cow 1 after a further course of four injections in its next pregnancy. Two hundred ml of colostrum from cow 1 (after the second course of vaccine) was given to 12 newborn colostrum-deprived lambs. All showed a high concentration of antitoxin 48 hours later. The lambs were actively immunised by injections of the same clostridial vaccine at three and nine weeks or six and 12 weeks old and all produced sufficient antitoxin to protect up to slaughter at 24 weeks. It is concluded that colostrum from cows vaccinated with sheep clostridial antigens can be fed to protect lambs passively.  相似文献   
120.
A course called Health Management 1 was created as part of a new DVM curriculum at the Ontario Veterinary College. This full year course was designed to introduce students to basic concepts of health management, integrating the disciplines of epidemiology, ethology, and public health in the context of selected animal industries. The course was comprised of 60 lecture hours and four two-hour laboratories. A common definition of health management, incorporating five principles, was used throughout the course, in order to reinforce the concepts and to maintain continuity between lecture blocks. Unlike in the years prior to the introduction of the new curriculum, epidemiology was presented as a tool of health management rather than as a separate discipline. To supplement the lecture and laboratory material, a Web-based resource was created and the students were required to review the appropriate section prior to each lecture block. Small quizzes, consisting of 10 questions each within WebCT, were used to stimulate self-directed learning. Overall, the course was well received by the students. The Web resources combined with the WebCT quizzes proved to be an effective method of stimulating students to prepare for lecture.  相似文献   
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