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51.
Chlamydia pecorum (designated 22–58) was isolated in 2010 in HmLu-1 cells from the jejunum of a calf which died of necrotizing enterocolitis in Yamaguchi Prefecture, Japan. Immunohistochemical staining identified C. pecorum positive reactions in the jejunal villi. C. pecorum, designated 24–100, was isolated from the feces of a calf with diarrhea in another farm in Yamaguchi Prefecture in 2012. A significant increase in neutralizing antibody titers against C. pecorum was confirmed in paired sera. Nucleotide sequence identities of omp1 genes of the 2 isolates were 100%. The isolates were genetically and antigenically more closely related to C. pecorum Bo/Yokohama strain isolated from cattle with enteritis in Japan than to the other prototype strains, Bo/Maeda isolated from cattle with pneumonia and Ov/IPA isolated from sheep with polyarthritis. These results indicate that C. pecorum strains similar to 22–58 and 24–100 might be endemic in Yamaguchi Prefecture and cause enteric disease in cattle.  相似文献   
52.
Agricultural soil is a major source of nitrous oxide (N2O), and the application of nitrogen and soil drainage are important factors affecting N2O emissions. This study tested the use of polymer-coated urea (PCU) and polymer-coated urea with the nitrification inhibitor dicyandiamide (PCUD) as potential mitigation options for N2O emissions in an imperfectly drained, upland converted paddy field. Fluxes of N2O and methane (CH4), ammonia oxidation potential, and ammonia-oxidizing bacteria (AOB) and ammonia-oxidizing archaea (AOA) abundances were monitored after the application of PCU, PCUD, and urea to upland soil. The results showed that urea application increased the ammonia oxidation potential and AOB and AOA abundances; however, the increase rate of AOB (4.6 times) was much greater than that of AOA (1.8 times). These results suggested that both AOB and AOA contributed to ammonia oxidation after fertilizer application, but the response of AOB was greater than AOA. Although PCU and PCUD had lower ammonia oxidation potential compared to urea treatment, they were not effective in reducing N2O emissions. Large episodic N2O emissions (up to 1.59 kg N ha?1 day?1) were observed following heavy rainfall 2 months after basal fertilizer application. The episodic N2O emissions accounted for 55–80 % of total N2O emissions over the entire monitoring period. The episodic N2O emissions following heavy rainfall would be a major source of N2O in poorly drained agricultural fields. Cumulative CH4 emissions ranged from ?0.017 to ?0.07 kg CH4 ha?1, and fertilizer and nitrification inhibitor application did not affect CH4 oxidation.  相似文献   
53.
ABSTRACT:   The effects of dietary taurine levels and lipid contents on the conjugated bile acid composition and growth performance of juvenile Japanese flounder Paralichthys olivaceus were investigated. Six types of diet (three different levels of taurine at two different levels of lipid) were fed to juveniles (average body weight, 0.04 g). Fishmeal that was washed with 70% ethanol to remove taurine was used as the sole protein source. Feeding experiments were carried out at 20°C for 6 weeks. At the end of the experiments, fish were weighed and analyzed for free amino acids in the body and the composition of the conjugated bile acids. The body weight and percent weight gain of the juveniles were improved by the dietary taurine supplementation. The taurine contents of the whole body and tissues increased with the increase of the dietary taurine contents. The conjugated bile acids in the gall bladder consisted of taurocholic acid and taurochenodeoxycholic acid, which increased with the increase of the dietary taurine level. Taurocholic acid accounted for more than 95% of the total conjugated bile acids. This indicates that taurine is the sole amino acid to conjugate bile acid in Japanese flounder.  相似文献   
54.
Hepatozoon sp. infections were detected in two species of Japanese wild cat, Iriomote wild cat (Felis iriomotensis) and Tsushima leopard cat (Felis bengalensis euptilura), between April 1993 and October 2005. The prevalence was 56.7% (17/30) and 14.3% (6/42), respectively. The most affected organ was the heart; all infected animals had organisms in their hearts. The parasitizing form was schizont and various developmental stages were observed. The size of schizont and merozoite was 22.3 +/- 3.1 x 15.3 +/- 2.2 mum and 6.1 +/- 0.6 x 2.3 +/- 0.2 mum, respectively. Few inflammatory reactions against the parasites were observed. Electron microscopically, organisms were located in parasitophorous vacuoles of unidentified host cells, and mature schizonts consisted of numerous merozoites. This is the first report of hepatozoonosis in Japanese felids.  相似文献   
55.
An experiment was conducted with 16 Japanese Black cows to determine the effects of different days on feed (89, 208, 271 and 341 days), inclusion levels of grain in concentrate (60% vs. 40%; dry matter (DM) basis) and roughage sources (hay vs. rice straw) on finishing performance. Additional four cows were slaughtered at 0 days on feed to obtain non‐fed carcass data. Maximum carcass weights were observed in cows fed for 271 days; an increase in carcass weight of only 14 kg was shown from 208 days to 271 days. The marbling score increased (P < 0.05) with days on feed. The percentage of fat in the subprimal rib linearly increased (P < 0.05) with days on feed. The percentage of lean meat was higher (P < 0.05) for cows fed rice straw than for cows fed hay as a roughage source. Increasing the days on feed decreased (P < 0.05) the yellowness of the fat. The effects of the inclusion levels of grain in concentrate on the finishing performance of cows were lower than the other two factors. In conclusion, feeding improves carcass values, but feeding over 208 days is an inefficient system of production in cows.  相似文献   
56.
We investigated whether regular changes of the sire in a breeding farm of Hokkaido Native Horses (HKDs) enables the DNA‐level genetic variation of the produced animals to be maintained. The genotypes of 31 microsatellite markers were identified and analyzed in 207 animals produced in a breeding farm in which the sire was replaced every 3 to 5 years. The mean allele number indicating the degree of genetic variation was 5.97 and was similar to those reported previously. The mean observed heterozygosity was 0.74 and was higher than the expected heterozygosity, 0.69; FIS was ?0.07, indicating that the analyzed animals reflected frequent outbreeding and had maintained genetic variation. Based on genetic structural analysis, the number of genetic subpopulations of the animals was estimated to be as 6, and the majority (more than 50%) of each subpopulation corresponded to the progeny of one of the sires used in the breeding farm; these observations suggested that genetic variation in the analyzed animals reflected the genetic differences among sires. Pedigree records indicated that the average co‐ancestry coefficient between sires used in the breeding farm was 0.015 corresponding to second cousin. This level of kinship among sires is acceptable for producing HKDs that maintain genetic variation.  相似文献   
57.
58.
The study of spatial distribution of secondary metabolites within microbial cells facilitates the screening of candidate strains from marine environments for functional metabolites and allows for the subsequent assessment of the production of metabolites, such as antibiotics. This paper demonstrates the first application of Raman microspectroscopy for in situ detection of the antifungal antibiotic amphotericin B (AmB) produced by actinomycetes—Streptomyces nodosus. Raman spectra measured from hyphae of S. nodosus show the specific Raman bands, caused by resonance enhancement, corresponding to the polyene chain of AmB. In addition, Raman microspectroscopy enabled us to monitor the time-dependent change of AmB production corresponding to the growth of mycelia. The Raman images of S. nodosus reveal the heterogeneous distribution of AmB within the mycelia and individual hyphae. Moreover, the molecular association state of AmB in the mycelia was directly identified by observed Raman spectral shifts. These findings suggest that Raman microspectroscopy could be used for in situ monitoring of antibiotic production directly in marine microorganisms with a method that is non-destructive and does not require labeling.  相似文献   
59.
Summary A couple of near-isogenic lines, JR and JW from Portulaca sp. Jewel has red and white petals respectively. The difference in petal color in the two lines is caused by an alteration of single genetic locus which is involved in the biosynthesis of betalain pigmentation. In order to detect this genetic difference at the polypeptide level, we have now attempted the comparative analysis of petal proteins between JR and JW. The protein profiles of SDS-polyacrylamid gel electrophoresis from three different stages of the developing petals, and the autoradiographic protein profiles of in vivo labeled petals howed that a 27 KD fragment strongly appeared as a characteristic of JR petal fraction. Thus, this fragment can be considered as a candidate for certain polypeptides which is associated with the betalain synthesis pathway functioning in the pigmented petals.Abbreviations SDS sodium-dodecyl sulfate - KD kilo-dalton - DOPA 3,4-dihydroxyphenylalanine  相似文献   
60.
Enteric bacteria, especially Escherichia coli, have been isolated from porcine livers affected with ascariasis. We hypothesized that reason for this bacterial isolation was due to bacterial translocation (BT). In order to clarify the association between ascariasis and isolation of Enterobacteriaceae in the livers,12 pigs with ascariasis (ascariasis group), 12 pigs without ascariasis (non-ascariasis A group) were used. Jejunum, ileum, cecum, colon, livers, mesenteric lymph nodes (MLN), and portal blood were obtained from these pigs. Furthermore, in order to confirm the presence of BT in pigs, the samples mentioned above as well as spleens were obtained from 11 pigs without ascariasis (non-ascariasis B group) and 6 specific pathogen free (SPF) pigs without ascariasis (non-ascariasis SPF group). In the first experiment, the gram-negative bacteria were isolated from livers (66.7%), MLN (91.7%), and portal blood (55.6%) regardless the presence of ascariasis. In the second experiment, isolation rates of gram-negative and -positive bacteria were 52.9 and 66.7% for livers, 52.9 and 80% for MLN, 11.8 and 26.7% for spleens, and 40 and 20% for portal blood of the pigs examined, respectively. E. coli and Staphylococcus were the predominant isolates from these pigs. A large number of antigens immunodetected by E. coli polyclonal antibody were found in the damaged cecal mucosa. These findings present evidence that BT is generally observed in slaughtered pigs regardless the presence of ascariasis. This has challenged our notion that extraintestinal organs of pigs are usually maintained as sterile.  相似文献   
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