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1.
A massive unilateral scrotal pyocele caused by Staphylococcus capitis in a 6‐year‐old ram is reported. Ultrasound examination of the right hemiscrotum showed an irregular hyperechoic mass in an anechoic fluid. A dense exudate was collected from the scrotum for microbiological analysis. Grossly, there was an extensive greenish purulent exudate and a completely atrophied right testis. Coagulase‐negative S. capitis was isolated in pure culture. To the authors' knowledge, this is the first report of genital infection by S. capitis in rams. This microorganism should be included in the differential diagnosis of ovine genital infections.  相似文献   
2.
The relationships of live animal muscular and skeletal scores and ultrasound measurements and carcass conformation and fat scores with carcass composition and value were determined using 74 bulls. The animals consisted of 53 late-maturing breed crosses and 21 Holstein–Friesian slaughtered at 13 to 17 months of age. They were offered concentrates ad-libitum and 1 kg of grass silage dry matter per head daily for the final 139 day finishing period. Live animal muscular and skeletal scores and ultrasonic muscle and fat depth measurements of the M. longissimus dorsi were recorded at 8 to 12 months of age and pre-slaughter. Following slaughter, carcasses were classified for conformation and fatness and the right side of each carcass was dissected into meat, fat and bone. Carcass conformation and fat scores, (scale 1 to 15) ranged from 4.7 to 14.4 and 2.7 to 11.5, respectively. Pre-slaughter muscular scores showed significant positive correlations with kill-out proportion (r = 0.82), carcass meat proportion (r = 0.72), conformation score (r = 0.94), carcass value (r = 0.72), and the proportion of high-value meat cuts in the carcass (r = 0.49), and significant negative correlations with carcass bone (r = − 0.89) and fat (r = − 0.32) proportions. The associations between pre-slaughter muscular scores and proportion of high-value cuts in meat, perinephric plus retroperitoneal fat and fat score were not significant. Corresponding correlations with muscular scores at 8 to 12 months of age were generally lower than those recorded pre-slaughter. Correlations of ultrasound muscle depth with carcass traits showed similar trends but lower values to those obtained using the muscular scoring procedure. Ultrasound fat depth pre-slaughter was positively correlated with carcass fat proportion (r = 0.56) and fat score (r = 0.54), and negatively correlated with carcass meat proportion, proportion of high-value cuts and carcass value. Correlations with other carcass traits were not significant. Correlations of live animal skeletal scores with carcass traits were generally non-significant. A one unit (scale 1–15) increase in carcass conformation score was associated with significant increases in kill-out proportion, meat yield and carcass value of 11.9 g/kg, 11.9 g/kg and 5.8 cent/kg, respectively. Corresponding effects for a one unit change in fat score were − 2.9 g/kg, − 11.1 g/kg and − 4.9 c/kg. In conclusion, live animal muscular scores and ultrasound measurements and carcass conformation and fat scores were shown to be useful predictors of carcass composition and value.  相似文献   
3.
This study examined germination and dormancy in Galeopsis speciosa (Lamiaceae), a common summer annual weed in cold‐temperate areas. Seeds collected in southern Sweden were subjected to several experiments. The seeds were dormant at maturity. Seeds sown outdoors after collection produced a small number of seedlings that emerged early in the spring. After long cold stratification or stratification outdoors over two winters, the maximum germination was 40–50%; germination occurring over a wide range of temperatures. Warm stratification preceding cold stratification had no effect on germination, but repeated warm and cold periods seemed to promote germination. Gibberellic acid (GA) stimulated germination, but full germination was only achieved after more than 2 months of incubation at the most suitable temperature regime tested. Excised embryos grew and developed into normal seedlings. With these results, the species does not fit into the currently used system for seed dormancy classifications. The response to GA and the growth of excised embryos indicate non‐deep or intermediate physiological dormancy, but dormancy alleviation by stratification was not in line with the guiding principles for these classifications. Galeopsis speciosa has a strong dormancy that is sufficiently alleviated during the winter to allow germination of only part of a seed batch each year; hence a stepwise germination pattern occurs over a period of several years.  相似文献   
4.
Rising temperatures caused by climate change are likely to affect cool‐water and warm‐water fishes differently. Yet, forecasts of anticipated temperature effects on fishes of different thermal guilds are lacking, especially in freshwater ecosystems. Towards this end, we used spatially explicit, growth rate potential (GRP) models to project changes in seasonal habitat quality for a warm‐water piscivore (largemouth bass Micropterus salmoides), a cool‐water piscivore (walleye Sander vitreus) and a hybrid piscivore (saugeye S. vitreus × S. canadensis) in two Midwestern reservoirs. We assessed habitat quality for two periods (early and middle 21st century) under two realistic greenhouse gas emission scenarios (a mid‐century emissions peak and a rapid continuous increase in emissions). Largemouth bass were projected to experience enhanced or slightly reduced habitat during all seasons, and throughout the mid‐21st century. By contrast, walleye habitat was projected to decline with anticipated warming, except during the spring in the smaller of our two study reservoirs and during the fall in the larger of our two study reservoirs. Saugeye habitat was projected to either increase modestly or decline slightly during the spring and fall and declines in habitat quality and quantity that were smaller than those for walleye were identified during summer. Collectively, our findings indicate that climate warming will differentially alter habitat suitability for reservoir piscivores, favouring warm‐water species over cool‐water species. We expect these changes in habitat quality to impact the dynamics of reservoir fish populations to varying degrees necessitating the consideration of climate when making future management decisions.  相似文献   
5.
The objective of this study was to examine the effect of donor breed on pronuclear‐stage embryo yield to be used for DNA microinjection in a transgenesis goat program. Twelve Canindé and twelve Saanen goats were heat synchronized using a progestagen‐cloprostenol treatment. Forty‐eight hours before the sponge removal, superovulation was induced with a total administration of 4.4 mg/kg bodyweight NIH‐FSH‐P1, given twice daily in decreasing doses over 3 days. In addition, goats received 100 μg of GnRH and they were hand‐mated at 36 and 48 h after progestagen removal. Embryo recovery was performed by oviduct flushing at 72 h after sponge removal. Embryos were microinjected with a DNA construct and noticeable swelling of the nuclei was the criterion for successful microinjection. The total diameter, cytoplasm diameter, zona pellucida thickness and pronuclei diameter were measured for each microinjected embryo. A higher (p < 0.05) percentage of fertilized ova was observed in Canindé (89.9%) than Saanen (36.2%) goats. In addition, Canindé donors produced a higher percentage of pronuclear embryos when compared with Saanen: 72.5% vs 20.6% (p < 0.05), respectively. Successful microinjection was verified in 96.7% and 73.3% of times in Canindé and Saanen embryos, respectively (p < 0.05). Significant differences were observed for all morphometric parameters except for cytoplasm diameter. In conclusion, under our study experimental conditions, Canindé were more efficient than Saanen goats concerning the pronuclear embryo yield and manipulation. The use of Canindé goats in transgenesis programs could be increase the interest in their breeding and could be contribute to saving them from extinction.  相似文献   
6.
Objectives To assess a method for monitoring depth of anaesthesia using components of middle latency auditory evoked potential (AEP) waveforms during anaesthesia with fentanyl/fluanisone and midazolam. Study design Prospective observational study. Animals Five female Wistar rats weighing between 210 and 250 g. Methods Implanted electrodes were used to record AEPs in animals receiving five doses of anaesthetic. Recordings were made at 5 minutes post‐injection (deep anaesthesia; no pedal withdrawal response, PWR) and then at 25 minutes (light anaesthesia; strong PWR). Responses showed five characteristic peaks occurring at 11, 14, 23, 42 and 68 ms that were measured for latency of occurrence and peak amplitude. Results Auditory evoked potential peaks P14, N23 and P42 were increased significantly in latency with successive anaesthetic injections [avg. F(1,4) = 12.53, p < 0.001; avg. F(1,4) = 10.6, p < 0.001; avg. F(1,4) = 3.9, p = 0.02, respectively]. Peak N23 showed a significant reduction in latency during the 20 minute recovery period following both the first and second anaesthetic injections (t(3) = 7.52, p = 0.005; t(4) = 5.17, p = 0.007, respectively). Peak P42 occurred significantly earlier 20 minutes following the second anaesthetic injection (t(4) = 4.75, p = 0.009). The mean overall depth of anaesthesia assessed using PWR scores was significantly correlated with the mean latency of peak N23, such that as the strength of PWR increased, N23 occurred significantly earlier (r = ?0.99, p = 0.01). The amplitude difference between peaks N23 and P42 increased after the second and third drug administrations [avg. F(1,4) = 10.65, p = 0.031 and avg. F(1,4) = 11.24, p = 0.028, respectively]. Conclusion The characteristics of these peaks, and in particular latency of peak N23, may provide a useful tool for assessing depth of anaesthesia produced by this, and possibly other anaesthetic agents.  相似文献   
7.
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   
8.
The Marketplace Fairness Act (S. 743) recently passed by the U.S. Senate may portend a national move toward states imposing sales taxes for business‐to‐consumer e‐retail purchases. While much of the policy debate surrounding this question has focused on trade creation versus diversion, there are likely distinct compositional effects at the state level, which will affect both economic activity and tax revenue. Consumers are clearly hurt by an online sales tax. However, such a policy would seemingly benefit state tax coffers, as well as traditional brick‐and‐mortar retailers and their employees. This paper uses a computable general equilibrium model approach to get a better understanding of the state‐level income, employment, and tax revenue effects of such a policy shift, in particular the likely tradeoffs between these three traditional economic targets across reasonable ranges of price elasticities.  相似文献   
9.
10.
The eyes are a common site of injury in agricultural operations. Identification of the cause of injury is important to inform preventive interventions. The objective of this study was to describe the hazards and mechanisms of acute traumatic injury to the eyes of agricultural workers who are hired in farming operations on a seasonal basis. A review of the literature was performed to summarize the mechanisms of eye injuries in agriculture. Field observations and informal interviews were performed to verify the literature and to determine whether there are eye hazards for farm workers that have not been reported in the literature. Additional mechanisms of injury were elicited, and suggested methods of injury prevention are presented here.  相似文献   
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