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101.
Histiocytic proliferative disorders in canine central nervous system (CNS) including granulomatous meningoencephalomyelitis (GME) and malignant histiocytosis were compared pathologically. Lesions of GME mainly existed in the white matter of the cerebrum, brainstem and cerebellum and consisted of characteristic perivascular cuffing, parenchymal granuloma and leptomeningeal infiltrates of mononuclear cells. In malignant histiocytosis, there were two histological patterns, diffuse proliferation of neoplastic histiocytes through the leptomeninges and neoplastic nodule formation in the parenchyma. Neoplastic histiocytes exhibited mild to severe cellular atypia and high ability of invasion into the brain parenchyma. Mitotic and phagocytic figures were also observed. Several histiocytic markers, including lysozyme, alpha1-antitrypsin and lectin RCA-1, revealed histiocytic origin of both inflammatory and neoplastic cells, however, those were not determinative for the discrimination between GME and malignant histiocytosis. CD3- and PCNA-positive cells existed in the lesions of both diseases. The number of CD3-positive cells in GME tended to be greater than in malignant histiocytosis, while the difference was not statistically significant.  相似文献   
102.
Diagnosis and management of twin pregnancies in the mare are an ongoing challenge in equine reproduction. Early detection of twin and manual crush of one vesicle are the main steps in the management of twins. Few studies were carried out about the use of transvaginal ultrasound-guided aspiration (TUGA) for reduction of twins in the mare. In this study, the efficiency of TUGA for management of twin pregnancies was investigated. Reduction of unicornuate twins between 16 and 25 days of gestation gave a success rate of 70.0% (14 viable foals/20 twin pregnancies); when reduction was performed after day 40 of gestation, all mares (one unicornuate; three bicornuate) lost both. For those cases in which the window for early crush of a twin vesicle has been missed, TUGA can be successfully used to reduce twin pregnancy between 16 and 25 days of gestation.  相似文献   
103.
Control of Penicillium expansum by plant volatile compounds   总被引:1,自引:0,他引:1  
Nine plant volatiles were tested for their activity in vitro and in vivo against Penicillium expansum , the cause of blue mould of pear. In vitro spore germination and mycelial growth assay showed a consistent fungicidal activity by trans -2-hexenal, carvacrol, trans -cinnamaldehyde and citral, while hexanal (-)- carvone, p -anisaldehyde, eugenol and 2-nonanone exhibited a progressively lower inhibition. trans -2-Hexenal was the best inhibitor of conidial germination [MIC (minimum inhibitory concentration) = 24·6  µ L L−1; ED50 = 10·2  µ L L−1], while carvacrol was the best inhibitor of mycelial growth (MIC = 24·6  µ L L−1; ED50 = 9  µ L L−1). The four most active compounds in in vitro studies were tested in vivo as fumigants against blue mould on pear cv. Conference. Best control was achieved by trans -2-hexenal vapour treatments (12·5  µ L L−1) when applied over a 24-h period, beginning 24 h after inoculation. In contrast, carvacrol (12·5–200  µ L L−1), and trans -cinnamaldehyde (50–400  µ L L−1) were ineffective and citral (200  µ L L−1) showed only slight effect.  相似文献   
104.
105.
Postharvest biological treatment entails a range of different approaches, including strengthening of the commodity’s natural defense mechanisms and application of antagonistic microorganisms and natural antimicrobial substances. Postharvest biological treatment has highlighted the potential of antagonistic microorganisms (fungi, bacteria and yeasts) against a limited number of pathogens, and only on specific hosts. Further studies are therefore required to identify antagonists with a broad spectrum of activity. The resistance of fruits and vegetables to postharvest diseases is closely linked to the ripening process, and drops markedly with the onset of tissue senescence: It is now possible to protect the product by inducing disease resistance. Plants produce a large number of secondary metabolites with antimicrobial effect on the main postharvest pathogens. Detailed studies have been conducted on aromatic compounds, essential oils and volatile substances. Combination of the above complementary techniques could well lead to effective control of postharvest fungal diseases.  相似文献   
106.
OBJECTIVE: To assess bioequivalence after oral, IM, and IV administration of racemic ketoprofen in pigs and to investigate the bioavailability after oral and IM administration. ANIMALS: 8 crossbred pigs. PROCEDURES: Each pig received 4 treatments in a randomized crossover design, with a 6-day washout period. Ketoprofen was administered at 3 and 6 mg/kg, PO; 3 mg/kg, IM; and 3 mg/kg, IV. Plasma ketoprofen concentrations were measured by use of high-performance liquid chromatography for up to 48 hours. To assess bioequivalence, a 90% confidence interval was calculated for the area under the time-concentration curve (AUC) and maximum plasma concentration (C(max)). RESULTS: Equivalence was not detected in the AUCs among the various routes of administration nor in C(max) between oral and IM administration of 3 mg/kg. The bioavailability of ketoprofen was almost complete after each oral or IM administration. Mean +/- SD C(max) was 5.09 +/- 1.41 microg/mL and 7.62 +/- 1.22 microg/mL after oral and IM doses of 3 mg/kg, respectively. Mean elimination half-life varied from 3.52 +/- 0.90 hours after oral administration of 3 mg/kg to 2.66 +/- 0.50 hours after IV administration. Time to peak C(max) after administration of all treatments was approximately 1 hour. Increases in AUC and C(max) were proportional when the orally administered dose was increased from 3 to 6 mg/kg. Conclusions and Clinical Relevance: Orally administered ketoprofen was absorbed well in pigs, although bioequivalence with IM administration of ketoprofen was not detected. Orally administered ketoprofen may have potential for use in treating pigs.  相似文献   
107.
A latex agglutination test for detecting Echinococcus multilocularis coproantigen in definitive hosts was developed using latex beads sensitized with EmA9 monoclonal antibody raised against somatic antigens of adult E. multilocularis. A primary test (LA 1) was performed on 82 fecal samples of necropsied foxes, of which 46 were infected, and resulted in 61% sensitivity and 86% specificity. To increase the sensitivity, 4 ng/mL of excretory/secretory antigens of adult worms was added to the samples in a secondary test (LA 2), resulting in 91% sensitivity and 61% specificity. The positive predictive value of the LA 1 test and the negative predictive value of the LA 2 test were both 85%. The combination of the LA 1 and LA 2 tests is applicable and practical for use in situations that require quick diagnosis or screening based on the following interpretation: the samples that are positive in the LA 1 test are positive; the samples that are negative in the LA 2 test are negative; and the samples that are negative in the LA 1 test and positive in the LA 2 test are classified as suspicious.  相似文献   
108.
A severe outbreak of enteric and respiratory disease associated with bovine coronavirus (BCoV) infection is described. The outbreak occurred in a dairy herd of southern Italy in the first decade of September 2006, when summer temperatures were still recorded, affecting calves, heifers and adult cows, with a marked decrease in milk production. By virus isolation and RT-PCR targeting the S gene, BCoV was identified as the etiological agent of the outbreak, whereas bacteriological, parasitological and toxicological investigations failed to detect other causes of disease. BCoV strains with 99-100% nucleotide identity in the S gene were isolated from nasal, ocular and rectal swabs, thus proving the absence of separate clusters of virus on the basis of tissue tropism. Sequence analysis of the haemagglutination-esterase and spike proteins of the strain detected in one rectal sample (339/06) showed a high genetic relatedness with recent BCoV isolates (98-99% amino acid identity), with several unique amino acid substitutions in the S protein. The BCoV outbreak described in this paper presents interesting aspects: (i) the occurrence of a severe form of disease in the warmer season; (ii) the simultaneous presence of respiratory and enteric disease; (iii) the involvement of young as well as adult cattle.  相似文献   
109.
Acoustic Doppler current profiler (ADCP) data collected during routine monitoring surveys of the distribution and abundance of Japanese sardine larvae ( Sardinops melanostictus ) off the Pacific coast of Japan in February 1993 and 1994 were used to construct stationary average flowfields for three levels in the upper 100 m in each year. No large-scale meanders in the path of the Kuroshio Current were present in either year, but the axis of the current was closer to the coast in 1993 than in 1994. The flowfields were used to drive a particle-tracking model representing the dispersal of sardine eggs and larvae. Particles were released in accordance with the observed distribution of eggs, and their positions tracked for up to 40 days. In 1993, the model indicated that ≈ 50% of the egg production was carried north-eastwards out of the survey area into the area of the NW Pacific referred to as the Kuroshio Extension Zone. In contrast, only 5% of the egg production was exported to the Extension Zone in 1994, the remainder being retained in Japanese coastal waters. The consequences of the different dispersal patterns are discussed in relation to subsequent recruitment to the sardine stock. Based on commercial catch data, survival of the 1993 year class was 15% of that for the 1994 class. Hence, the results indicate that export of larvae to the Kuroshio Extension cannot in itself lead to successful recruitment.  相似文献   
110.
Abstract In less-developed countries, fisheries enhancement using stocking is a common practice to manage reservoirs for biomass production. In many cases, there appears to be little control over whether the stocking activity is appropriate or necessary. Cuban reservoir fisheries have been usually managed to maximize fish biomass. Blue tilapia have been introduced and supplemented in reservoirs, and Chinese carp are introduced and maintained in reservoirs throughout the entire island. Supplemental stocking with introduced fish species is a usual practice to manage large and medium-sized reservoirs. Small and very small reservoirs have been managed as semi-intensively enhanced fisheries with carp and tilapia stocking. The main purposes of the present paper are to study the factors contributing to the outcome of stocking programmes in reservoirs and to test the hypotheses that supplementary stocking for self-sustained fish populations usually cannot contribute to increase fish yield. Yield and stocking data by groups of fish species were available for Cuban reservoirs. Total fish yield was only slightly related to total fish stocking density for the complete set of reservoirs. However, this result was mainly because of the relationship between total yield and cyprinid stocking for semi-intensively-used reservoirs. Tilapia yield was not significantly related to tilapia stocking for both extensively and semi-intensively-used reservoirs. However, yield and stocking for cyprinids were highly related for both reservoir subsets. Therefore, cyprinid stocking was effective in certain reservoirs, but tilapia stocking was not effective in any reservoir. Moreover, tilapia stocking was a superfluous activity for reservoirs where tilapia have an adequate natural reproduction cycle.  相似文献   
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