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11.
A long-term field experiment was initiated in November, 1967 at Research Area of Department of Soil Science to study the response of nitrogen to pearl millet-wheat cropping system at various doses and modes of farmyard manure application. The soil organic carbon increased with farmyard manure application and ranged from 0.68% in control to 1.82% in the plot receiving the highest annual dose (90 Mg ha?1) of farmyard manure. To study the contribution of farmyard manure on the productivity of pearl millet and wheat crops, the constants (intercept and slope) were determined between the grain yield of pearl millet and wheat crops with increasing dose of fertilizer nitrogen. Another linear regression was fitted between the intercept of the linear model and the soil organic carbon content. It has been observed that with each unit increase in the soil organic carbon, the productivity of pearl millet increased by 273 kg ha?1 and that of wheat by 1591 kg ha?1. The regression between the slope and soil organic carbon was linear in case of pearl millet (R2 0.49) but in case of wheat there was no relationship.  相似文献   
12.
Haematological studies were conducted on 10 clinically normal water buffalo calves to determine leucocytic responses to Escherichia coli endotoxin, prednisolone and dexamethasone. Intravenous injection of 10 micrograms endotoxin induced minimal decreases in leucocyte numbers, whereas 20, 50 and 100 micrograms produced a marked leucopenia within one hour. Moderate to marked leucopenia, neutropenia and lymphopenia persisted for three to 14 hours. Significant rebound neutrophilia was evident at six to eight hours after inoculation in calves given only 10 and 20 micrograms. Intramuscular injection of prednisolone (100 mg) and dexamethasone (5 mg) produced increases in total leucocyte counts and neutrophil numbers within two hours. Moderate to marked leucocytosis and neutrophilia persisted for eight to 24 hours. Lymphocyte response was unlike that in other species in that lymphopenia was not a consistent feature of the corticosteroid response. A transient monocytosis was seen following administration of prednisolone but not of dexamethasone, while eosinopenia and basopenia developed in both cases. In conclusion, endotoxin and corticosteroid induced changes in total and differential leucocyte counts in water buffalo were largely similar to those seen in cattle.  相似文献   
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Resistance in susceptible mustard cv. PR-15 against the highly virulent A. brassicae isolate A (AbA) and moderately virulent isolate C (AbC) was induced using an avirulent Alternaria brassicae isolate D (AbD). The induction of resistance due to AbD against AbA or AbC resulted in significant reduction in disease severity. The A. alternata (Aa) failed to induce resistance against AbA and AbC, on the contrary it induced susceptibility against them.  相似文献   
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Components of disease reaction, including incubation period, pustule types, inoculum production and disease index (DI); and contents of protein, phenols, soluble sugars and reducing and non-reducing sugars were investigated in cotyledonary and true leaves of six genotypes of Brassica juncea : Varuna, Kranti, EC-399296, EC-399299, EC-399313 and EC-399301, inoculated with Albugo candida . Cotyledonary leaves were examined 14 days after inoculation (d.a.i.), whereas true leaves were scored 14 and 21 d.a.i. Disease indices were assessed on a 0% (resistant) to 100% (susceptible) scale. DIs at the cotyledonary leaf stage in the above six genotypes were 67, 65, 32, 31, 31 and 38%, respectively, whereas at the true-leaf stage they were 21, 28, 12, 17, 9 and 4%, respectively at 14 d.a.i., and 35, 45, 17, 19, 20 and 6%, respectively at 21 d.a.i. Protein contents were highest in the genotypes with the highest DIs, such as Varuna at the cotyledonary leaf stage and Kranti at the true-leaf stage, and lowest in the genotypes with the lowest DIs, such as EC-399299 at the cotyledonary stage and EC-399301 at the true-leaf stage. Total phenols, total sugars, reducing sugars and non-reducing sugars were generally negatively correlated with DI, but were not always consistent, particularly when differences in DI were small. The results indicated that factors conditioning the response of host genotypes to A. candida may differ or operate in different ways at different growth stages.  相似文献   
17.
This study had the aim of investigating the efficiency of timed artificial insemination (TAI) through the progesterone‐releasing intravaginal device (PRID), used in new condition and for the second and third times in Nelore cows. The effects of device reuse and body condition score (BCS) on the conception rate (CR) were evaluated in 1,122 multiparous Nelore cows (mean BCS of 2.7 ± 0.4), which were randomly distributed into three groups that received new (n = 330), once (n = 439) and twice used (n = 353) PRID. Among the 1,122 females that underwent TAI, 573 became pregnant, thus representing an overall CR of 51.06%. Cows with BCS between 2.75 and 4.0 had greater (p < .0001) CR (69.75%) than cows with BSC of 2.0–2.5 (32.98%). It was observed that the CR through using PRID was 60.00%, 51.71% and 41.93% for new, once and twice used PRID, respectively, with difference between all groups (p < .0001). Under tropical conditions, animals with BCS greater than 2.5 had a higher CR, and the CR decreased proportionally with the number of times that the PRID had been used.  相似文献   
18.
Polyunsaturated fatty acids are important membrane components that influence membrane integrity and fluidity. In the present study, the effect of oral supplementation for 60 days with essential fatty acids (omega 3, 6 and 9) and vitamin E on canine semen quality was evaluated. Sixteen dogs were selected for the experiment; eight were used as the control group and eight received the fatty acid supplemented diet for 60 days. Semen samples were taken every 15 days during the entire experimental period and were analyzed for volume (ml), motility (%), vigour (0–5), concentration (×106/ml), morphology of spermatozoa (%), plasma membrane integrity (%; using the hyposmotic swelling test) and thermoresistance (motility and vigour after 4 h at 38°C). We concluded that, daily supplementation with omega 3, omega 6 and omega 9 fatty acids, together with vitamin E, for a period of 60 days, significantly increased the semen volume of the treated group after 15 days of supplementation; the vigour and concentration of spermatozoa were superior after the first month of supplementation, while the percentage of morphologically abnormal spermatozoa decreased and the cells were protected against thermal stress.  相似文献   
19.
前言目前畜牧生产的高效率是以下几方面因素综合作用的结果:1.畜牧生产者能迅速地接受新的饲养管理技术;2.遗传、营养和饲养管理方面的研究取得了非常有价值的成果,能够以尽可能低的成本生产优质的畜产品;3.政府鼓励科研的发展,为畜牧工作提出合理建议并制订必要的法规。在科学计算的基础上,应用配合饲料,特别是全价饲料(粉料或顺粒料)喂猪和禽能够迅速有效地将营养研究成果和革新技术应用到实际中去。全价饲料可以节省劳力,提高饲料  相似文献   
20.
ABSTRACT In an investigation of the interaction between two isolates of Albugo candida that were compatible (CO) and incompatible (IN) on a Brassica juncea accession, the IN isolate induced both local and systemic protection of cotyledons and true leaves against the CO isolate. The extent of the protection was proportional to the zoosporangia concentration used in the inducing (IN) inoculation. Protection was greatest locally on cotyledons and least on true leaves (the most remote tissue from the point of the inducing inoculation). Protection occurred when the two isolates were inoculated together but was greater when the interval between the IN and CO isolate inoculations was longer. The IN isolate induced only slight protection when it was inoculated after the CO isolate. No induced susceptibility to the IN isolate occurred with any treatment. There was some evidence of competition between CO and IN zoospores for infection sites (stomata). The occurrence of systemic protection and changes detected in phenylalanine ammonia lyase and total soluble peroxidase activities in inoculated cotyledons, particularly after the inducing (IN) inoculation, suggested that host-mediated factors also may be involved in the interaction between the two isolates.  相似文献   
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