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The aim of this study was to investigate in 20 healthy pigs the practicability of the oesophagogastroduodenoscopic examination technique in regard to equipment, method of examination, indications and its suitability as a diagnostical tool for the assessment of the oesophagus, stomach and upper duodenum in one procedure. Preparation of the patient for endoscopy, the procedure of the endoscopic examination as well as the topographical findings of the upper intestinal tract including the duodenum until the flexura duodenojejunalis are described. Flexible oesophagogastroduodenoscopy is a suitable method for the observation and natural visualisation of mucosal surfaces and for the digital documentation of peristaltic movements. The procedure is easy to perform in anaesthetized animals, is in most cases completed within 15 min, and can be repeated in the same animal. Indications of this interesting diagnostic imaging technique are discussed.  相似文献   
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Frequency distribution of females according to weaning-to-estrus interval (WEI) was evaluated in a database containing 15,600 breeding records of one Brazilian farm. The consequences of WEI duration on the reproductive performance was evaluated, emphasising on the effect of very short WEI (0 to 2 days). Only females with WEI up to 21 days, lactation length of 13 to 26 days and parity 1 to 8 were included in the analyses. The average WEI was 4.8 days and the percentage of females showing estrus within 2 days after weaning was 6.1%. In both primiparous (PO 1) and multiparous females (PO > 1) those with WEI of 3–5 days showed the lowest return to estrus rate. The highest RER and the lowest FR were observed when estrus occurred on the day after weaning, for primiparous sows, and on the day of weaning, for multiparous sows. In both parity classes, WEI of 0–2, 6–8, 9–12 and 13–18 days resulted in FR lower (P < 0.05) than those observed for WEI of 3–5 days. In PO 1 females, the lowest subsequent litter size (SLS) was observed in those with WEI of 6–8 and 9–12 days (P < 0.05). In PO > 1 females SLS increased significantly from WEI 0–2 to WEI 3–5 days, it decreased in females with WEI of 6–8 days and increased again in females with WEI of 9 to 21 days. A negative effect of WEI on reproductive performance is clear in females with very short WEI (0–2 days) and in those with WEI of 6–12 days.  相似文献   
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Improving flavour quality traits in fruit breeding calls for innovative consumer-oriented product development. This paper explores the potential of marker-assisted breeding from genomics and consumer-based quality-improvement models from marketing, and exploits the progresses at both sides as technology push and market pull. An integrative and cross-disciplinary quality-improvement model is proposed based on Bayesian modelling. This Bayesian modelling allows for the integration of elicited knowledge of breeders and flavour researchers concerning the degree of causal associations of metabolites and flavour quality traits of fruits in the model. We also present the flavour quality improvement challenge as a multi-criteria optimization process and show the potential and current limitations of the proposed model. Insights gained from the model would help flavour researchers determine the optimum concentration of flavour-affecting metabolites which could be used for further DNA marker development. These ideas and concepts will help translate consumer-desired product features into genomic information, ultimately resulting in successful new cultivars.  相似文献   
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ObjectivesTo describe dye distribution and spinal nerve involvement after a simulated erector spinae plane (ESP) block performed on fresh equine cadavers.Study designExperimental cadaver study.AnimalsA group of 11 adult equine cadavers.MethodsThe spinal region surrounding the sixteenth thoracic vertebra (Th16) of one cadaver was removed and underwent magnetic resonance imaging. In 10 adult equine cadavers [body weight, 549 ± 58 kg (mean ± standard deviation)], 0.2 mL kg–1 of a 50:1 2% lidocaine/dye solution was injected bilaterally (n = 20 injections) into the fascial plane between the transverse process of Th16 and the erector spinae muscles. An in-plane ultrasound-guided technique with a convex transducer was used to guide injection. Dissection was performed immediately following injection. The craniocaudal and lateral extent of dye distribution was measured (cm) and the number of vertebral bodies involved were counted (n = 20). Abdominal and thoracic cavities as well as the epidural space were also examined for presence of dye (yes/no) (n = 20). Further dissection was performed to evaluate if staining of the dorsal and ventral rami of the spinal nerves and sympathetic chain occurred (n = 14).ResultsThe thoracolumbar fascia was stained in 17/20 (85%) injections and three injections terminated intramuscularly. Multisegmental staining of the dorsal rami was observed in the 14 injections in which staining was evaluated. Ventral rami staining was observed in 3/14 injections where staining was evaluated. Epidural migration was observed in 4/20 (20%) injections. No evidence of dye was found in the thoracic and abdominal cavities or on the sympathetic chain.Conclusions and clinical relevanceThe ESP block may prove beneficial to desensitize structures innervated by the dorsal rami of the thoracic spinal nerves. Further investigation is necessary to evaluate complications caused by epidural contamination.  相似文献   
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Relatively few studies have documented the impacts of afforestation, particularly production forestry, on belowground carbon dioxide (CO2) effluxes to the atmosphere. We evaluated the changes in the soil CO2 efflux—a proxy for soil respiration (Rs)—for three years following a native grassland conversion to eucalypt plantations in southern Brazil where minimum tillage during site preparation created two distinct soil zones, within planting row (W) and between-row (B). We used root-exclusion and carbon (C)- isotopic approaches to distinguish Rs components (heterotrophic-Rh and autotrophic-Ra respirations), and a CO2 profile tube (1-m deep) to determine the concentration ([CO2]) and isotopic C signature of soil CO213[CO2]). The soil CO2 efflux in the afforested site averaged 0.37 g CO2 m?2 h?1, which was 56% lower than the soil CO2 efflux in the grassland. The δ13CO2 in the afforested site ranged from ? 14.1‰ to ? 29.4‰, indicating a greater contribution of eucalypt-derived respiration (both Rh and Ra) over time. Higher soil CO2 efflux and lower [CO2] were observed in W than B, indicating that soil preparation creates two distinct soil functional zones with respect to C cycling. The [CO2] and δ13[CO2] decreased in both zonal positions with eucalypt stand development. Although the equilibrium in C fluxes and pools across multiple rotations is needed to fully account for the feedback of eucalypt planted forests to climate change, we provide quantitative information on soil CO2 dynamics after afforestation and show how soil preparation can leverage the feedback of planted forests to climate change.

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Kinesin motor proteins are thought to move exclusively in either one or the other direction along microtubules. Proteins of the kinesin-5 family are tetrameric microtubule cross-linking motors important for cell division and differentiation in various organisms. Kinesin-5 motors are considered to be plus-end-directed. However, here we found that purified kinesin-5 Cin8 from budding yeast could behave as a bidirectional kinesin. On individual microtubules, single Cin8 motors were minus-end-directed motors, whereas they switched to plus-end-directed motility when working in a team of motors sliding antiparallel microtubules apart. This kinesin can thus change directionality of movement depending on whether it acts alone or in an ensemble.  相似文献   
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