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131.
Cotyledons (n=170) from dairy cattle were analysed for Coxiella burnetii by real-time (rt) PCR targeting the IS1111a and icd genes. Positive cases (n=90) and a random selection of negative cases (n=20) were examined by histology, immunohistochemistry and, if infection level was high, by fluorescence in situ hybridisation. PCR results were compared to bulk tank milk (BTM) antibody levels. Placental infection was detected in cows from herds at all BTM antibody levels. However the likelihood of placental infection was generally higher in herds with intermediate or high BMT antibody levels than in herds with low antibody levels. Histological examination revealed a range of mostly mild cotyledonary changes; C. burnetii infection was only rarely associated with inflammation. This may explain why bovine Q fever is usually not clinically apparent. Nevertheless, infected cattle will shed C. burnetii at calving and this can occur even in herds without BTM antibodies.  相似文献   
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The lignans podophyllotoxin and deoxypodophyllotoxin are secondary metabolites with potent pharmaceutical applications in cancer therapy. However, the supply of podophyllotoxin from its current natural source, Podophyllum hexandrum, is becoming increasingly problematic, and alternative sources are therefore urgently needed. So far, podophyllotoxin and deoxypodophyllotoxin have been found in some Juniperus species, although at low levels in most cases. Moreover, extraction protocols deserve optimization. This study aimed at developing and validating an efficient extraction protocol of podophyllotoxin and deoxypodophyllotoxin from Juniperus species and applying it to 13 Juniperus species, among which some had never been previously analyzed. Juniperus bermudiana was used for the development and validation of an extraction protocol for podophyllotoxin and deoxypodophyllotoxin allowing extraction yields of up to 22.6 mg/g DW of podophyllotoxin and 4.4 mg/g DW deoxypodophyllotoxin, the highest values found in leaf extract of Juniperus. The optimized extraction protocol and HPLC separation from DAD or MS detections were established and validated to investigate podophyllotoxin and deoxypodophyllotoxin contents in aerial parts of 12 other Juniperus species. This allowed either higher yields to be obtained in some species reported to contain these two compounds or the occurrence of these compounds in some other species to be reported for the first time. This efficient protocol allows effective extraction of podophyllotoxin and deoxypodophyllotoxin from aerial parts of Juniperus species, which could therefore constitute interesting alternative sources of these valuable metabolites.  相似文献   
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Purpose  

Environmentally hazardous and health risk substances in animals and humans in the environment have increased as a result of continuing anthropogenic activities. Examples of these activities are food processing, laboratory, food production, industrial, and other relative activities that use various forms of acrylamide. All acrylamide in the environment are manmade. It is the building block for the polymer, polyacrylamide, which is considered to be a nontoxic additive. However, if the polymerization process is not perfect and complete, the polyacrylamide may still contain acrylamide which is toxic and may pose risks and hazards to the environment. Another form of acrylamide that may pose danger as well in the environment is the acrylamide monomer, which is also a very toxic organic substance that could affect the central nervous system of humans and is likely to be carcinogenic. Phytoremediation could be a tool to somehow absorb this neurotoxic agent and lessen the contamination in the soil. This technology could lessen the soil and water contamination by acrylamide thereby limiting the exposure of animals and humans. This study may also help solve the problem of disposing contaminated acrylamide waste materials. This study was conducted to achieve the following objectives: (1) to evaluate phytoremediation potentials of some selected tropical plants in acrylamide-contaminated soil, (2) to compare the performance of tropical plants in absorbing acrylamide through accumulation in their roots and shoots, and (3) to determine the outcome of acrylamide in the soil after treatment using the test plants with phytoremediation potentials.  相似文献   
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Three groups with 12 weanling male albino rats were group fed for 90 days on a standard laboratory rat diet plus 20% coconut oil either without a supplement or with the addition of 10% curry leaf or 10% mustard seeds. Feed was offered at a level of 10% body weight. At the end of the trial, measurements were made on the total serum cholesterol, high density lipoproteins, low density lipoproteins, and very low density lipoproteins fractions, release of lipoproteins into the circulation, lecithin cholesterol acyl transferase activity and lipoprotein lipase activity. Feed intake and mean body weight of the rats on each treatment was not significantly different. Both spices resulted in a reduction in total serum cholesterol and LDL+VLDL, an increase in the HDL, lower release of lipoproteins into the circulation and an increase in the LCAT activity.  相似文献   
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Citrus root meristems, 300 to 500μ long, are able to grow in vitro and sometimes exhibit shoot differentiation spontaneously. Cultured on appropriate media such roots regenerate shoots and complete plants may be obtained.  相似文献   
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The humoral and cell-mediated immune (CMI) response to 2 commercial killed Salmonella Enteritidis (SE) vaccines (Layermune and MBL SE4C) was evaluated in laying hens. Layers were distributed in 2 experimental groups. The first received a single immunization at 16 wk of age, while the second experimental group was immunized at 12 wk of age and again at 18 wk of age. Serum immunoglobulin (Ig)G antibodies were measured using a commercial SE ELISA kit and showed persistent levels from 3 to 32 and 34 wk post-vaccination. The vaccination protocol using 2 immunizations showed a higher seroconversion level than the single vaccination. However, our results for bacterial intracellular survival indicated that IgG titers were not linked with bacterial killing. Local IgA production was measured in the intestines and oviducts with an in-house SE whole cell antigen ELISA. Only the MBL SE4C vaccine elicited IgA antibody production when tested on intestine and oviduct mucosal secretions, 3-weeks post-vaccination in both immunization protocol groups. To evaluate the CMI response, the splenic T-cells and B-cells populations were analyzed using flow cytometry. The CD3/B-cell ratio decreased 3 wk after the second immunization in the twice vaccinated Layermune group due to an increase in B-cells.  相似文献   
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Aloe vera gel is a familiar ingredient in a range of widely available and advertisement healthcare and cosmetic products. As to date there are no documented reports on the standardization of A. vera gel and the following study is an attempt in this direction. A. vera gel was evaluated for its aloeverose content for the first time. Aloeverose, was separated on a thin-layer of silica gel by isocratic gradient elution technique was determined by using HPTLC-photodensitometry. The proposed method is simple and sensitive and can be used for the routine assay of aloeverose in phytomedicines containing A. vera gel.  相似文献   
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