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101.
A method of protecting free methionine from partial ruminal degradation utilizing a lipid-protein matrix was developed. Eight wether lambs were fitted with abomasal cannulae and utilized in a 4 X 4 Latin square design experiment to determine the effectiveness of the protection matrix. The squares were blocked by animal and time, with each animal receiving each of the four diets. The diets were: (1) a negative control tall fescue and corn-based diet containing no added methionine; (2) a positive control diet that contained 3 g of methionine with ground corn, zein, coconut oil and methionine each added individually; (3) the control diet 1 supplemented with a methionine, ground corn, zein and coconut oil matrix that provided 3 g methionine/d; and (4) the control diet 1 containing the methionine matrix to provide 6 g methionine/d. Digestibility and balance data were obtained by collecting feces and urine over a 7-d period, followed by a day of blood sampling at 2, 4 and 6 h postfeeding. Abomasal samples were then subsequently collected over 3 d on a time schedule that represented every 2 h. Feeding protected methionine decreased (P less than .08) urinary N by .69 g/d and increased (P less than .08) N retention by 1.07 g/d. Plasma urea N was decreased (P less than .003) by 2.06 mg/100 ml and plasma free methionine increased (P less than .001) by 1.94 mumol/100 ml in lambs fed the protected methionine matrix. These data indicate that coating free methionine with the preparation described herein was partially effective in delivering methionine to the absorptive sites and subsequently to the tissues of the ruminant animal.  相似文献   
102.
Budgerigars ( Melopsittacus undulatus ) from two different breeding colonies were found to have Giardia infection. Light microscopy, scanning electron microscopy and in-vitro and in-vivo studies confirmed the species was G psittaci . Chicks were clinically affected and showed signs of retarded growth, dehydration and diarrhoea. The faeces of adult birds treated with metronidazole in drinking water were negative for Giardia 5 days after treatment. Megabacteria were also found in adult birds but were not treated. This study extends the known host range for Giardia in Australia to include budgerigars.  相似文献   
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Objective

To characterise the minimum dose of intramuscular alfaxalone required to facilitate intubation for mechanical ventilation, and to investigate the impact of cranial versus caudal injection on anaesthetic depth.

Study design

Randomised crossover study.

Animals

Six healthy juvenile ball pythons (Python regius).

Methods

Three dosages (10, 20 and 30 mg kg–1) of alfaxalone were administered to each python in a caudal location with a minimum 2 weeks washout. Induction and recovery were monitored by assessing muscle tone, righting reflex, response to a noxious stimulus and the ability to intubate. A subsequent experiment assessed the influence of injection site by comparing administration of 20 mg kg–1 alfaxalone in a cranial location (1 cm cranial to the heart) with the caudal site. Respiration rate was monitored throughout, and when intubation was possible, snakes were mechanically ventilated.

Results

Regardless of dose and injection site, maximum effect was reached within 10.0 ± 2.7 minutes. When administered at the caudal injection site, intubation was only successful after a dosage of 30 mg kg-1, which is higher than in previous reports for other reptiles. However, intubation was possible in all cases after 7.2 ± 1.6 minutes upon cranial administration of 20 mg kg–1, and anaesthetic duration was significantly lengthened (p < 0.001). Both 30 mg kg–1 at the caudal site and 20 mg kg–1 at the cranial site led to apnoea approximately 10 minutes post-injection, at which time the snakes were intubated and mechanically ventilated.

Conclusions and clinical relevance

Alfaxalone provided rapid, smooth induction when administered intramuscularly to pythons, and may serve as a useful induction agent prior to provision of volatile anaesthetics. The same dosage injected in the cranial site led to deeper anaesthesia than when injected caudally, suggesting that shunting to the liver and first-pass metabolism of alfaxalone occur when injected caudally, via the renal portal system.  相似文献   
107.
The objectives of this study were to determine (i) if in subtropical goats that gave birth during mid‐December, the exposition to an artificial long‐day photoperiod consisting in only 14 hr of light per day can increase the milk yield and (ii) to test whether these females can respond to the male effect at the end of the prolonged photoperiodic treatment. In experiment 1, 17 lactating goats were maintained under natural short days (control group), while another 22 goats were maintained under artificial long days (treated group) consisting in 14 hr light and 10 hr darkness starting at day 10 of lactation. The continuous exposition to an artificial long‐day photoperiod produced an increase in the milk yield level during the first 110 days of lactation (time × treatment interaction; = .01), while none of the milk components were modified due to the photoperiodic treatment (> .05). In experiment 2, all control and treated anovulatory goats were submitted to the male effect using photostimulated males. All females showed oestrous behaviour within the first 10 days that were in contact with males (100% in both groups; > .05). Thus, the latency to onset of oestrus did not differ between females from control (58.2 ± 3.0 hr) and treated (62 ± 4.6 hr) groups. Male exposition provoked ovulation independently if females were previously under long days or natural photoperiod (96 vs 100%, respectively; = .79). It was concluded that exposure to 14 hr of light per day in subtropical goats that gave birth in late autumn stimulates milk yield without preventing the ovulation in response to the male effect at the end of the prolonged photoperiodic treatment.  相似文献   
108.
CASE HISTORY AND CLINICAL FINDINGS: During April and May 2014 four horses aged between 5 months and 9 years, located in the Canterbury, Marlborough and Southland regions, presented with a variety of clinical signs including recumbency, stiffness, lethargy, dehydration, depression, and myoglobinuria suggestive of acute muscle damage. Two horses were subjected to euthanasia and two recovered. In all cases seeds of sycamore maple (Acer pseudoplatanus) or box elder (A. negundo) were present in the area where the horse had been grazing.

LABORATORY INVESTIGATION: The samaras (seeds) of some Acer spp. may contain hypoglycin A, that has been associated with cases of atypical myopathy in Europe and North America. To determine if hypoglycin A is present in the samaras of Acer spp. in New Zealand, samples were collected from trees throughout the country that were associated with historical and/or current cases of atypical myopathy, and analysed for hypoglycin A. Serum samples from the four cases and four unaffected horses were analysed for the presence of hypoglycin A, profiles of acylcarnitines (the definitive diagnosis for atypical myopathy) and activities of creatine kinase and aspartate aminotransferase.Markedly elevated serum activities of creatine kinase and aspartate aminotransferase, and increased concentrations of selected acylcarnitines were found in the case horses. Hypoglycin A was detected in the serum of those horses but not in the healthy controls. Hypoglycin A was detected in 10/15 samples of samaras from sycamore maple and box elder from throughout New Zealand.

DIAGNOSIS: Cases of atypical myopathy were diagnosed on properties where samaras containing hypoglycin A were also found.

CLINICAL RELEVANCE: Sycamore and box elder trees in New Zealand are a source of hypoglycin A associated with the development of atypical myopathy. If pastured horses present with clinical and biochemical signs of severe muscle damage then the environment should be checked for the presence of these trees. Horses should be prevented from grazing samaras from Acer spp. in the autumn.  相似文献   

109.
AIM: To determine the period prevalence of needlestick injury (NSI) at the Massey University Veterinary Teaching Hospital (VTH) and to identify handling and disposal practices that may contribute to the risk of NSI.

METHODS: Observations of personnel were conducted in the equine (EVH) and companion animal (CAH) clinics of the VTH during scheduled clinical activities over 9- and 10-day periods, respectively. The number and type of NSI incidents, needle uncapping, capping and disposal events were recorded for veterinarians, nurses and other personnel (visitors and students). The number of needle-related practices, as a proportion of observations, were compared between CAH and EVH, and veterinarians, nurses and others using χ2 tests.

RESULTS: Needlestick injury was not observed during 190 and 163 needle handling and disposal observations in the CAH and EVH, respectively. Uncapping of needles by mouth was observed and was practised more by veterinarians (15/119; 13%) than nurses (2/42; 5%) and others (6/193; 3%) (p=0.001). Two-handed needle recapping after use was observed 265/354 times, and the one handed scooping technique was rarely observed (8/352). In the case of needle disposal, EVH workers used a container that was not purpose built for disposal more than CAH staff (p=0.02), or placed them in a pocket more frequently (p=0.003). Needle disposal containers were available on adjacent bench tops for 65/190 (34%) CAH observations, but no EVH observations. For 51/163 (31%) EVH observations the needle disposal containers were located on the ground, whereas none were observed there in the CAH. No approved sharps containers were observed in the immediate EVH and CAH work areas for 47/163 (28.8%) and 1/191 (0.5%) needle-handling activities, respectively.

CONCLUSIONS: Unsafe needle-handling practices must be reduced by policies and training programmes to encourage safe needle-related practices, and ensuring that approved sharps containers are available in close proximity to where needles are used.  相似文献   

110.
BACKGROUND: Most insect‐resistant transgenic crops employ toxins to control pests. A novel approach is to enhance the effectiveness of natural enemies by genetic engineering of the biosynthesis of volatile organic compounds (VOCs). Before the commercialisation of such transgenic plants can be pursued, detailed fundamental studies of their effects on herbivores and their natural enemies are necessary. The linalool/nerolidol synthase gene FaNES1 was constitutively expressed from strawberry in three Arabidopsis thaliana accessions, and the behaviour of the aphid Brevicoryne brassicae L., the parasitoid Diaeretiella rapae McIntosh and the predator Episyrphus balteatus de Geer was studied. RESULTS: Transgenic FaNES1‐expressing plants emitted (E)‐nerolidol and larger amounts of (E)‐DMNT and linalool. Brevicoryne brassicae was repelled by the transgenic lines of two of the accessions, whereas its performance was not affected. Diaeretiella rapae preferred aphid‐infested transgenic plants over aphid‐infested wild‐type plants for two of the accessions. In contrast, female E. balteatus predators did not differentiate between aphid‐infested transgenic or wild‐type plants. CONCLUSION: The results indicate that the genetic engineering of plants to modify their emission of VOCs holds considerable promise for facilitating biological control of herbivores. Validation for crop plants is a necessary next step to assess the usefulness of modified volatile emission in integrated pest management. Copyright © 2012 Society of Chemical Industry  相似文献   
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