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1.
SUMMARY The proposal by the Zoological Parks Board of New South Wales to import 10 southern black rhinoceros (Diceros bicornis) from Zimbabwe as part of an international project for conservation of the species presented the Australian Quarantine and Inspection Service (AQIS) with a unique challenge. This importation is, at least in the modern era, the first importation of live herbivores from the African continent. Many of the serious animal diseases in the world are endemic in parts of Africa. Knowledge of which of these diseases infect wild species and may be transmitted from the wild species to domesticated species, is limited. This paper describes the strategies adopted by AQIS to facilitate the importation of rhinoceros while maintaining protection of Australian consumers, rural industries, domestic livestock and fauna against the entry and spread of unwanted pests and diseases.  相似文献   
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A cohort study was carried out on 112 breeding pig farms in England to investigate the impact of type of farrowing accommodation on preweaning mortality in piglets. Four types of farrowing accommodation were studied; farrowing crates, indoor loose pens, crate/loose systems (where the sow was restrained in a crate during birth and the first days of lactation before being moved to a loose pen) and outdoor farrowing in arcs in paddocks. Four estimates of preweaning mortality were collected: an oral estimate from the farmer before the visit, an estimate from the 6-month rolling average from computer records, records from 20 litters observed when the farm was visited and prospective records collected from 20 farrowings after the visit. These four estimates were significantly correlated. The prospective records also included a farmer reported date and cause of death. From the prospective data there were 25,031 piglets from 2143 litters from 112 farms, 6.5% of piglets were stillborn while live born preweaning mortality was 12%. Mixed effect discrete time survival, binomial and competing risk, models were used to investigate the association between preweaning mortality and farrowing accommodation, controlling for sow parity, litter size and number of piglets stillborn and fostered. There was a reduced risk of stillbirths in outdoor farrowing systems compared with crated systems. Farmers reported that crushing of healthy piglets was the most frequent cause of death accounting for 55% of live born preweaning mortality. There was no significant difference in mortality in live born piglets by farrowing system. There was a significantly higher risk of farmer reported crushing of healthy live born piglets in outdoor arcs compared with piglets reared with sows in farrowing crates and a significantly reduced risk of death from causes other than crushing in piglets reared outdoors or in crate/loose systems compared with piglets reared in crated systems. We conclude that, in the farms in this study, farrowing crates reduced the risk of preweaning live born mortality attributable to crushing but piglets in this system were at increased risk of death from other causes. Consequently crates had no significant effect on overall preweaning mortality percentage. In all four commercial production systems; outdoor, farrowing crates, crate/loose farrowing systems and indoor loose housed systems, there were similar levels of mortality.  相似文献   
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A sampling protocol for the thyrotropin-stimulation test in the horse   总被引:1,自引:0,他引:1  
A study was designed to assess the secretory response of thyroid glands in horses to an economically feasible dose (5 IU) of thyrotropin injected IV, and to establish valid blood sampling periods in cases in which thyroxine concentrations were different from base-line values. Significant (P less than 0.001) response (doubling or near-doubling of base line) occurred as early as 3 hours after thyrotropin administration, with peak response at 4 to 5 hours. It was concluded that administration of 5 IU of thyrotropin is economical and effective in the horse, with collection of a second blood sample possible as early as 3 hours after administration.  相似文献   
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Objective The aims of this work were to (1) develop a low-cost equine movement tracking collar based on readily available components, (2) conduct preliminary studies assessing the effects of both paddock size and internal fence design on the movements of domestic horses, with and without foals at foot, and (3) describe distances moved by mares and their foals. Additional monitoring of free-ranging feral horses was conducted to allow preliminary comparisons with the movement of confined domestic horses. Procedures A lightweight global positioning system (GPS) data logger modified from a personal/vehicle tracker and mounted on a collar was used to monitor the movement of domestic horses in a range of paddock sizes and internal fence designs for 6.5-day periods. Results In the paddocks used (0.8–16 ha), groups of domestic horses exhibited a logarithmic response in mean daily distance travelled as a function of increasing paddock size, tending asymptotically towards approximately 7.5 km/day. The distance moved by newborn foals was similar to their dams, with total distance travelled also dependent on paddock size. Without altering available paddock area, paddock design, with the exception of a spiral design, did not significantly affect mean daily distance travelled. Feral horses (17.9 km/day) travelled substantially greater mean daily distances than domestic horses (7.2 km/day in 16-ha paddock), even when allowing for larger paddock size. Conclusions Horses kept in stables or small yards and paddocks are quite sedentary in comparison with their feral relatives. For a given paddock area, most designs did not significantly affect mean daily distance travelled.  相似文献   
6.
Visually guided reaching in infant monkeys after restricted rearing   总被引:4,自引:0,他引:4  
Infant macaques were reared from birth in an apparatus which pre cluded sight of their body parts. At 35 days postpartum one hand was exposed to view. Visual fixation of this hand was insistent and prolonged; visually guided reaching was poor, but it improved during ten succeeding hours of exposure. Little concomitant improvement occurred in the reaching of the unexposed hand.  相似文献   
7.
The original article to which this Correction refers was published in Pest Management Science 58 (7): 649–662 (2002).Copyright © 2004 Society of Chemical Industry  相似文献   
8.
Osteochondroma of the distal portion of the radius was diagnosed in 3 horses with a history of lameness and distention of the common tendon sheath of the superficial and deep digital flexor tendons at the level of the carpal canal. In 2 horses, the exostosis was removed through an incision at the caudal border of the lateral digital extensor muscle above the carpal ligament.  相似文献   
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Interaction of a new fungicidal compound, viz. 2, 4, 5-trichlorophenylsulphonylmethyl thiocyanate with spores of Fusarium culmorum has been investigated.The compound is readily taken up by spores and converted to the non-fungitoxic 2,4,5-trichlorophenylsuphinic acid, which is released into the ambient solution. Uptake of the thiocyanate can be markedly reduced by pretreatment of the spores with a thiol reagent like iodoacetic acid and slightly enhanced by pretreatment with a thiol, like dithiodglycol. Moreover, the thiocyanate reacts with thiols in vitro by forming the same sulphinic acid. Hence, it is concluded that the title compound is able to react with fungal cell thiols.However, addition of a thiol reagent does not affect the fungitoxicity of the thiocyanate. The absence of synergism suggests that the fungitoxicity of the thiocyanate is based at least partly on reaction with fungal cell thiols.The thiocyanate investigated resembles the fungicide captan with respect to both uptake pattern and failure to give synergism with a thiol reagent. These observations suggest that the fungicidal compounds have a similar mode of action, as far as reaction with fungal cell thiols is concerned.Samenvatting De interactie van een nieuwe fungicide verbinding nl. 2,4,5-trichloorfenylsulfonylmethyl thiocyanaat met sporen vanFusarium culmorum is onderzocht.De verbinding wordt goed door sporen opgenomen en omgezet in het niet fungitoxische 2,4,5-trichloorfenylsulfinezuur, dat aan de buitenoplossing wordt afgestaan. Opname van het thiocyanaat kan in aanzienlijke mate worden verlaagd door voorbehandeling van de sporen met een thiolreagens zoals joodazijnzuur, en enigszins worden verhoogd door voorbehandeling met een thiol zoals dithiodiglycol. Voorts reageert het thiocyanaat met thiolen in vitro onder vorming van hetzelfde sulfinzuur. De conclusie wordt getrokken, dat het thiocyanaat in staat is te reageren met thiolen van de schimmelcel.Toevoeging van een thiolreagens heeft echter geen invloed op de fungicide werking van het thiocyanaat. Het uitblijven van synergisme suggereert, dat de fungitoxiciteit van het thiocyanaat tenminste gedeeltelijk is gebaseerd op reacties met thiolen in de schimmelcel.Het onderzochte thiocyanaat gelijkt op het fungicide captan niet alleen in opnamepatroon maar ook wat betreft het uitblijven van synergisme met een thiolreagens. Deze waarnemingen suggereren dat de fungicide verbindingen hetzelfde werkingsmechanisme hebben, althans voorzover het reacties met thiolen van de schimmel betreft.  相似文献   
10.
A partial skeleton of a primitive bird, Rahona ostromi, gen. et sp. nov., has been discovered from the Late Cretaceous of Madagascar. This specimen, although exhibiting avian features such as a reversed hallux and ulnar papillae, retains characteristics that indicate a theropod ancestry, including a pubic foot and hyposphene-hypantra vertebral articulations. Rahona has a robust, hyperextendible second digit on the hind foot that terminates in a sicklelike claw, a unique characteristic of the theropod groups Troodontidae and Dromaeosauridae. A phylogenetic analysis places Rahona with Archaeopteryx, making Rahona one of the most primitive birds yet discovered.  相似文献   
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