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Although nitrogen (N) has the highest requirement for plant growth, N use efficiency (NUE) seldom exceeds 40%. NUE may be improved by integrated application of fertilizer N and enriched organic amendments. The present experiment aimed to test the extent of increase in NUE by integrated application of fertilizer N farmyard manure (FYM) and rock phosphate enriched compost (RPEC). Mineralization kinetics and N release from FYM and RPEC were studied by an incubation experiment. Results revealed that maximum potentially mineralizable N as well as N release (283.9, 186.7 mg kg?1 soil, respectively) were from RPEC + fertilizer N treated soils, followed by FYM + fertilizer N. Maximum yield, N uptake, and N recovery were obtained from RPEC + fertilizer N treated soils followed by FYM + fertilizer N. Soils treated with RPEC had shown significantly higher dehydrogenase activity than FYM treated soils. Thus, RPEC might increase yield as well as NUE over FYM. N uptake by plant at maximum tillering stage and flowering stage of wheat correlated positively (R2 > 0.85) with the decay rate (k and kN0) parameter of incubation experiment suggesting their relevance as indicators of plant available N.  相似文献   
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Rural people in developing countries including India continue to access a number of types of ‘forests’ to meet specific needs such as fuelwood, fodder, food, non-timber forest produce and timber for both subsistence and income generation. While a plethora of terms exist to describe the types of forests that rural people use—such as farm forests, social forests, community forests and small-scale forests—the expression domestic forest has recently been proposed. Domestic forest is a term aimed at capturing the diversity of forests transformed and managed by rural communities and a way to introduce a new scientific domain that recognises that production and conservation can be reconciled and that local communities can be effective managers. This paper argues in the context of the central Western Ghats of south India that while the domestic forest concept is a useful umbrella term to capture the diversity of forests used by rural people, these domestic forests are often not autonomous local forests but sites of contestation between local actors and the state forest bureaucracy. Hence, a paradigm shift within the forest bureaucracy will only occur if the scientific forestry community questions its own normative views on forest management and sees forest policy as a means to recognise local claims and support existing practices of forest dependent communities.  相似文献   
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Receiver operating characteristic (ROC) analysis is a useful statistical tool to visualize, organize, and select diagnostic variables. Accuracy of the test is represented by the area under the ROC curve (AUC), sensitivity (Se), and specificity (Sp). In the present study, ROC analysis of prepartum feeding time (day ?11 to day ?2) of 20 pluriparous Holstein-Friesian crossbred cows were recorded, and the cows were followed up for detecting postpartum metritis development if any. Prepartum daily feeding time data during whole study was grouped into 2 periods (P1 [day ?11 to day ?7] and P2 [day ?6 to day ?2]). The AUC of feeding time for the P1 and P2 periods was 0.64 (P = 0.29) and 0.86 (P = 0.006), respectively. Cows with daily feeding times below the optimum threshold value of 284.5 min/d during P2 (Se = 75% and Sp = 91.67%) had more chance of developing postpartum metritis compared with those with daily feeding time above the threshold value (positive likelihood ratio = 9.0). Furthermore, relative risk (RR) analysis revealed that the risk of development of postpartum metritis increased as feeding time decreased below the optimum threshold value during P2 (RR = 5.571, P = 0.004). Thus, the optimum threshold value of feeding time during P2 may be used to predict risk of postpartum metritis, allowing for preventive measures to be implemented in the early postpartum period to reduce the likelihood of postpartum complications.  相似文献   
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This cross-sectional study was conducted to determine the prevalence and antimicrobial resistance of Salmonella species in swine reared in the intensive (indoor) and extensive (outdoor) ABF production systems at farm and slaughter in North Carolina, U.S.A. We sampled a total of 279 pigs at farm (extensive 107; intensive 172) and collected 274 carcass swabs (extensive 124; intensive 150) at slaughter. Salmonella species were tested for their susceptibility against 12 antimicrobial agents using the Kirby-Bauer disk diffusion method. Serogrouping was done using polyvalent and group specific antisera. A total of 400 salmonellae were isolated in this study with a significantly higher Salmonella prevalence from the intensive (30%) than the extensive farms (0.9%) (P<0.001). At slaughter, significantly higher Salmonella was isolated at the pre- and post-evisceration stages from extensively (29% pre-evisceration and 33.3% post-evisceration) than the intensively (2% pre-evisceration and 6% post-evisceration) reared swine (P<0.001). The isolates were clustered in six serogroups including B, C, E1, E4, G and R. Highest frequency of antimicrobial resistance was observed against tetracycline (78.5%) and streptomycin (31.5%). A total of 13 antimicrobial resistance patterns were observed including the pentaresistant strains with ampicillin, chloramphenicol, streptomycin, sulfamethoxazole, tetracycline resistance pattern observed only among isolates from the intensive farms (n=28) and all were serotype Salmonella typhimurium var. Copenhagen. In conclusion, this study shows that multidrug resistant Salmonella are prevalent in ABF production systems despite the absence of antimicrobial selection pressure. In addition, it also highlights the possible role played by slaughterhouse and other environmental factors in the contamination and dissemination of antimicrobial resistant Salmonella in ABF production systems.  相似文献   
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