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981.
K P Lander 《The British veterinary journal》1990,146(4):327-333
A transport and enrichment medium was developed for Campylobacter fetus. From inocula of between 10 and 35 organisms the medium was able to support the multiplication of 19 of 21 strains of C. fetus if the medium was incubated immediately after inoculation; when incubation was delayed for 3 days after inoculation, only seven of the 21 strains multiplied. From inocula of 100-350 organisms all 21 strains multiplied following immediate incubation, and 20 of 21 when incubation was delayed for 3 days. From inocula of about 10(4) organisms all strains multiplied following immediate or delayed incubation. The medium restricted the growth of Proteus vulgaris and Pseudomonas aeruginosa. 相似文献
982.
J C Lewis A J Fitzgerald F M Gulland C M Hawkey P Kertesz J K Kirkwood R A Kock 《The British veterinary journal》1989,145(4):394-396
Clinical experience of 73 cases of necrobacillosis in red-necked wallabies (Macropus rufogriseus) over a 6-year period is reviewed. Diagnostic methods and the medical and surgical treatment options are detailed. It is suggested that survival curves are necessary to assess the outcome of treatment. 相似文献
983.
Cell wall proteins (CWPs) play a vital role in the development of the different morphological stages including mycelium, fruiting body, and sclerotium in mushrooms which are important human food sources. Using fractionation by detergents and reducing agents, mushroom cell wall fractions from the different developmental stages of Pleurotus tuber-regium (PTR) were prepared. Using one-dimensional gel electrophoresis coupled with LC-MS, there were 103, 91, and 48 noncovalently linked CWPs identified in the cell wall fractions of the PTR mycelium, fruiting body, and sclerotium, respectively. Comparing the CWPs in these cell wall fractions, 19 of them were in common, among which 17 belonged to the functional categories of translation, ribosomal structure, and biogenesis. This is the first study to provide important biochemical insights into the different developmental stages of PTR mediated by CWPs, and the identified CWPs helped to explain the morphological changes of PTR mushrooms during cultivation. 相似文献
984.
Stergiadis S Leifert C Seal CJ Eyre MD Nielsen JH Larsen MK Slots T Steinshamn H Butler G 《Journal of agricultural and food chemistry》2012,60(29):7270-7281
There is increasing concern that the intensification of dairy production reduces the concentrations of nutritionally desirable compounds in milk. This study therefore compared important quality parameters (protein and fatty acid profiles; α-tocopherol and carotenoid concentrations) in milk from four dairy systems with contrasting production intensities (in terms of feeding regimens and milking systems). The concentrations of several nutritionally desirable compounds (β-lactoglobulin, omega-3 fatty acids, omega-3/omega-6 ratio, conjugated linoleic acid c9t11, and/or carotenoids) decreased with increasing feeding intensity (organic outdoor ≥ conventional outdoor ≥ conventional indoors). Milking system intensification (use of robotic milking parlors) had a more limited effect on milk composition, but increased mastitis incidence. Multivariate analyses indicated that differences in milk quality were mainly linked to contrasting feeding regimens and that milking system and breed choice also contributed to differences in milk composition between production systems. 相似文献
985.
Synchronizing rock clocks of Earth history 总被引:8,自引:0,他引:8
Kuiper KF Deino A Hilgen FJ Krijgsman W Renne PR Wijbrans JR 《Science (New York, N.Y.)》2008,320(5875):500-504
Calibration of the geological time scale is achieved by independent radioisotopic and astronomical dating, but these techniques yield discrepancies of approximately 1.0% or more, limiting our ability to reconstruct Earth history. To overcome this fundamental setback, we compared astronomical and 40Ar/39Ar ages of tephras in marine deposits in Morocco to calibrate the age of Fish Canyon sanidine, the most widely used standard in 40Ar/39Ar geochronology. This calibration results in a more precise older age of 28.201 +/- 0.046 million years ago (Ma) and reduces the 40Ar/39Ar method's absolute uncertainty from approximately 2.5 to 0.25%. In addition, this calibration provides tight constraints for the astronomical tuning of pre-Neogene successions, resulting in a mutually consistent age of approximately 65.95 Ma for the Cretaceous/Tertiary boundary. 相似文献
986.
Utilization of organic nitrogen (N) is an important aspect of plant N assimilation and has potential application in sustainable agriculture. The aim of this study was to investigate the plant growth, C and N accumulation in leaves and roots of tomato seedlings in response to inorganic (NH4^+-N, NO3^-N) and organic nitrogen (Gly-N). Different forms of nitrogen (NH4^+-N, NO3^--N, Gly-N) were supplied to two tomato cultivars (Shenfen 918 and Huying 932) using a hydroponics system. The plant dry biomass, chlorophyll content, root activity, total carbon and nitrogen content in roots and leaves, and total N absorption, etc. were assayed during the cultivation. Our results showed that no significant differences in plant height, dry biomass, and total N content were found within the first 16 d among three treatments; however, significant differences in treatments on 24 d and 32 d were observed, and the order was NO3^--N 〉 Gly-N 〉 NH4^+-N. Significant differences were also observed between the two tomato cultivars. Chlorophyll contents in the two cultivars were significantly increased by the Gly-N treatment, and root activity showed a significant decrease in NHa^+-N treatment. Tomato leaf total carbon content was slightly affected by different N forms; however, total carbon in root and total nitrogen in root and leaf were promoted significantly by inorganic and organic N. Among the applied N forms, the increasing effects of the NH4^+-N treatment were larger than that of the Gly-N. In a word, different N resources resulted in different physiological effects in tomatoes. Organic nitrogen (e.g., Gly-N) can be a proper resource of plant N nutrition. Tomatoes of different genotypes had different responses under organic nitrogen (e.g., Gly-N) supplies. 相似文献
987.
A pot experiment was conducted to evaluate the efficiency of farm yard manure (FYM) and lime (calcium carbonate) on reducing the uptake of Cd by rice in two Cd contaminated soils of Chittagong. The effects of farm yard manure, lime and farm yard manure mixed with lime (FYM + Lime) on rice (Oryza sativa L.) growth, Cd uptake by rice and 0.1 N HC1 extractable Cd in soil were investigated. Results showed that addition of lime and farm yard manure mixed with lime significantly decreased 0.1 N HCl extractable Cd in the city sewage soil. Application of farm yard manure significantly decreased Cd concentration in rice in the city sewage soil. Lime and farm yard manure mixed with lime significantly reduced Cd concentration in rice m both the contaminated soils. Lime was more efficient than farm yard manure in reducing the uptake of Cd by rice. 相似文献
988.
Determination of dissociation constants by two different methods yield the following mean values in 20 millimolar phosphate, pH 7.0, 25 degrees C: 0.27 micromolar for reduced nicotinamide adenine dinucleotide (NADH); 0.29 micromolar for NADH with deuterium in the nicotinamide 4-B position (B-NADD); and 0.46 micromolar for NADH with deuterium in the nicotinamide 4-A position (A-NADD). These results indicate that dehydrogenases are capable of recognizing and distinguishing the appropriate hydrogen in the coenzyme already in the initial binding reaction. 相似文献
989.
Svenja Hartung Elfi K. Schlohsarczyk Alexandra Jost Marlene Sickinger Kernt Khler 《Journal of veterinary diagnostic investigation》2022,34(2):298
In human and veterinary medicine, mixed Müllerian tumors (MMTs) are rarely diagnosed neoplasms of the tubular female genital tract. Although there are case reports of malignant MMTs in various species, benign MMTs have only been described once in a macaque. Here we present a case of benign MMT in a 12-y-old goat, and review the literature on uterine, cervical, and vaginal neoplasia in goats. The doe was presented with vaginal discharge and was euthanized because of the high suspicion of intraabdominal neoplasia. On gross examination, an ulcerated vaginal mass was identified. Histologically, 2 distinct cell populations were present: smooth muscle cells that were well differentiated and positive for alpha–smooth muscle actin, and ciliated columnar epithelial cells that lined ductal structures and had no signs of malignancy. These findings led to the diagnosis of neoplasia of Müllerian origin. Benign MMT should be considered as a differential diagnosis for uterine and vaginal neoplasms in goats. 相似文献
990.
K. R. Kelly B. H. Pypendop K. L. Christe 《Journal of veterinary pharmacology and therapeutics》2014,37(5):480-485
This study reports the pharmacokinetics of buprenorphine in conscious rhesus macaques (Macaca mulatta) after intravenous (i.v.) and intramuscular (i.m.) administration. Four healthy, opioid‐naïve, socially housed, adult male macaques were used. Buprenorphine (0.03 mg/kg) was administered intravenously as a bolus or intramuscularly on separate occasions. Blood samples were collected prior to, and up to 24 h, postadministration. Serum buprenorphine concentrations were analyzed with liquid chromatography–mass spectrometry. Noncompartmental pharmacokinetic analysis was performed with commercially available software. Mean residence time in the i.v. study as compared to the i.m. study was 177 (159–189) vs. 185 (174–214) min, respectively [median (range)]. In the i.v. study, concentration back‐extrapolated to time zero was found to be 33.0 (16.8–57.0) ng/mL [median (range)]. On the other hand, the maximum serum concentration found in the i.m. study was 11.8 (6.30–14.8) ng/mL [median (range)]. Rhesus macaques maintained concentrations >0.10 ng/mL for over 24 h in the i.v. study and over 12 h in the i.m. study. Bioavailability was found to be 68.1 (59.3–71.2)% [median (range)]. No significant adverse effects were observed in the monkeys at the 0.03 mg/kg dose of buprenorphine during either study. 相似文献