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81.
The predominant adrenergic protoalkaloid found in the peel and fruit of bitter orange, Citrus aurantium, is synephrine. Synephrine is reputed to have thermogenic properties and is used as a dietary supplement to enhance energy and promote weight loss. However, there exists some concern that the consumption of dietary supplements containing synephrine or similar protoalkaloids may contribute to adverse cardiovascular events. This study developed and validated a positive-ion mode liquid chromatography/tandem mass spectrometry (LC/MS/MS) method for the quantitative determination of the major (synephrine) and minor (tyramine, N-methyltyramine, octopamine, and hordenine) adrenergic protoalkaloids in a suite of National Institute of Standards and Technology (NIST) bitter orange Standard Reference Materials (SRMs): SRM 3258 Bitter Orange Fruit, SRM 3259 Bitter Orange Extract, and SRM 3260 Bitter Orange Solid Oral Dosage Form. The limit of quantitation (LOQ) for all protoalkaloids is approximately 1 pg on-column, except for octopamine (20 pg on-column). Additionally, the method has a linear dynamic range of > or =3 orders of magnitude for all of the protoalkaloids. Individual, as well as "total", protoalkaloid levels (milligrams per kilogram) in the NIST SRMs were determined and compared to the levels measured by an independent liquid chromatography/fluorescence detection (LC/FD) method. Satisfactory concordance between the LC/MS/MS and LC/FD protoalkaloid measurements was demonstrated. LC/MS/MS analysis of the protoalkaloids in the SRMs resulted in mean measurement imprecision levels of < or =10% coefficient of variation (% CV).  相似文献   
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83.
A cross-sectional survey investigating the contribution of free-range village chickens to household economies was carried out in four administrative districts within 60km of Accra. Answers were provided by 101 men and 99 women. Nearly all respondents claimed to keep chickens for meat, with a far smaller percentage claiming to keep them for egg production. Over 80% of respondents kept chickens to supplement their incomes. The proportion of the flock eaten varied between administrative areas (p=0.009 and p=0.027), although this was possibly a consequence of differences in consumption patterns between occupation of the respondent, land area cultivated and flock size. The proportion of chickens sold varied as a result of differences in flock size (p=0.013), the proportion sold increasing with number of birds in the flock. Respondents generally agreed that chickens could be sold without difficulty. A majority of chicken sales were from the farm gate, directly to consumers or traders. Sales were on demand or when the owner needed money. Money from the sale was kept by the owner of the chicken and the money was spent on personal needs. The proportion of the flock sold varied between administrative areas (p=0.025) and occupation of the respondent (p=0.040). Respondents describing animal production as their main occupation tended to have greater reliance on chicken sales for their income. Consideration is given to estimating the offtake from the flock and the financial contribution to the household.  相似文献   
84.
Forest fires release substantial amounts of carbon (C). Much of it is emitted to the atmosphere, but some is deposited within ash on the ground. Little is known about amount and types of C deposited in ash. Here, we quantify total C, and total inorganic, water-soluble and particulate organic fractions deposited in ash during the catastrophic 2009 ‘Black Saturday’ wildfires in Australia. These fires coincided with the highest air temperatures and lowest humidity ever recorded in the local area, which, combined with high fuel loads of mostly long unburnt eucalypt forests, generated extreme burning conditions. In three mixed-species eucalypt forest sites sampled, the canopy, understorey and litter fuels were almost completely consumed, resulting in substantial ash deposition (mean, 81.9 t ha?1), with 5.9 t ha?1 of C being transferred from vegetation to the forest floor. In five temperate rainforest sites sampled, the canopy was not burnt and ash deposition was lower (mean, 48.3 t ha?1) than in the mixed-species eucalypt forest, but overall their higher C content resulted in higher C deposition (8.1 t ha?1). In all cases, most C contained in ash was organic and its pyrogenic nature infers increased resistance to degradation. Pyrogenic C is viewed by many as an important C sink, which could contribute to long-term C sequestration when incorporated into soils or sediments. Our results highlight the potential importance of the pyrogenic C pool in freshly deposited ash and, therefore, the necessity of a systematic and detailed analysis of ash deposition and C forms in ash to improve our understanding of C fluxes by forest fires.  相似文献   
85.
A 2-week-old female Thoroughbred foal was born with a firm, expansile, progressively enlarging mass involving the left hemimandible. Grossly, the mass was composed of variably sized cavernous spaces containing clotted blood and serofibrinous exudate, separated by fibrous and fibroosseous septa. Histologically, the spaces were lined by flattened to plump spindle cells and contained hemorrhage, fibrin, and multinucleated osteoclast-like cells. The septa separating adjacent cavernous spaces contained interlacing bundles and streams of spindle cells, multinucleated giant cells, hemosiderophages, mineral deposits, and spicules and trabeculae of reactive and poorly mineralized bone. A diagnosis of congenital aneurysmal bone cyst was made based on histologic features. The pathogenesis for the development of aneurysmal bone cysts is still undetermined, although spindle cells lining cavernous spaces in the foal exhibited negative immunolabeling for factor-VIII (F8) and positive immunolabeling for smooth muscle actin, suggesting vascular smooth muscle origin and possible blood flow disturbance.  相似文献   
86.
Abstract: Mycobacterium avium paratuberculosis (Map) was cultured from the feces of a wild-caught, female, adult Southern black rhinoceros. The animal, which presented with a 4-mo history of diarrhea and weight loss, was prescribed a course of antimycobacterial drugs. The clinical signs resolved, and the feces were repeatedly culture negative thereafter. Although the Rhinocerotidae are likely to be resistant to Johne's disease, this case raises the possibility that they can become transiently infected with the causative organism.  相似文献   
87.
Flow cytometric sexing of spermatozoa followed by application in artificial insemination or in vitro fertilization provides a unique opportunity to predetermine the sex of offspring and might enhance the conservation management of endangered species in captivity such as the elephant and rhinoceros. To obtain an indication of the sortability of spermatozoa from these species, the relative DNA differences between X and Y chromosome bearing spermatozoa (fresh, frozen thawed, epididymal) from three rhinoceros species [white ( Ceratotherium simum ), black ( Diceros bicornis ), Indian ( Rhinoceros unicornis )] and both elephant species, the Asian and the African elephant ( Elephas maximus, Loxodonta Africana ), were determined through separation of spermatozoa into X and Y chromosome bearing populations, using a modified high speed flow cytometer. The head profile areas of spermatozoa from all five species were measured using light microscopy. By multiplying the relative DNA differences and the head profile areas, the sperm sorting indices were calculated to be 47, 48 and 51 for white, black and Indian rhinoceros respectively. The calculated sorting index for the Asian elephant was 66. In the African elephant, we determined the highest sorting index of 76. These results indicate the practicability of flow cytometric sex sorting of spermatozoa from the tested rhinoceros species and both elephant species. The lower sorting indices in rhinos indicate that sex sorting of spermatozoa from the rhinoceros will be more challenging than in elephants.  相似文献   
88.
We developed three different knowledge-dissemination methods for educating Tanzanian smallholder farmers about mastitis in their dairy cattle. The effectiveness of these methods (and their combinations) was evaluated and quantified using a randomised controlled trial and multilevel statistical modelling. To our knowledge, this is the first study that has used such techniques to evaluate the effectiveness of different knowledge-dissemination interventions for adult learning in developing countries.

Five different combinations of knowledge-dissemination method were compared: ‘diagrammatic handout’ (‘HO’), ‘village meeting’ (‘VM’), ‘village meeting and video’ (‘VM + V’), ‘village meeting and diagrammatic handout’ (‘VM + HO’) and ‘village meeting, video and diagrammatic handout’ (‘VM + V + HO’). Smallholder dairy farmers were exposed to only one of these interventions, and the effectiveness of each was compared to a control (‘C’) group, who received no intervention. The mastitis knowledge of each farmer (n = 256) was evaluated by questionnaire both pre- and post-dissemination.

Generalised linear mixed models were used to evaluate the effectiveness of the different interventions. The outcome variable considered was the probability of volunteering correct responses to mastitis questions post-dissemination, with ‘village’ and ‘farmer’ considered as random effects in the model. Results showed that all five interventions, ‘HO’ (odds ratio (OR) = 3.50, 95% confidence intervals (CI) = 3.10, 3.96), ‘VM + V + HO’ (OR = 3.34, 95% CI = 2.94, 3.78), ‘VM + HO’ (OR = 3.28, 95% CI = 2.90, 3.71), ‘VM + V’ (OR = 3.22, 95% CI = 2.84, 3.64) and ‘VM’ (OR = 2.61, 95% CI = 2.31, 2.95), were significantly (p < 0.0001) more effective at disseminating mastitis knowledge than no intervention.

In addition, the ‘VM’ method was less effective at disseminating mastitis knowledge than other interventions. Combinations of methods showed no advantage over the diagrammatic handout alone. Other explanatory variables with significant positive associations on mastitis knowledge included education to secondary school level or higher, and having previously learned about mastitis by reading pamphlets or attendance at an animal-health course.  相似文献   

89.
Total extract from the fruit of Szechuan pepper (Zanthoxylum piperitum DC), the volatile components of the extract and a non‐volatile fraction containing alkylamides (NVA fraction) are feeding deterrents for rats. The present study investigated the effectiveness of these natural repellents in prairie voles (Microtus ochrogaster Wagner). Two‐choice feeding trials were conducted during which food‐deprived voles were offered choices between oat‐bran wafers. In Experiment 1, 10 voles were given three sets of feeding trials, each 2 h long. Baseline consumption was established during the first set of two trials by offering a choice between two oat‐bran wafers dipped in ethanol, the control solvent. During the second set of two trials the voles were given a choice between an oat‐bran wafer dipped in ethanol and a wafer dipped in Zanthoxylum extract. During the third set the voles were given a choice between a wafer served on top of a screened dish containing a sample of ethanol and a wafer served on top of a dish containing a sample of extract. In this manner the voles were exposed to volatile compounds emanating from the extract but could not contact it. Wafers dipped in extract were almost completely avoided. The volatile components of extract also significantly reduced food intake. In Experiment 2, habituation to the volatile constituents of extract was examined in 16 Zanthoxylum‐naïve voles. Baseline consumption was established by offering two wafers served on top of screened dishes containing ethanol. This was followed by twelve tests during which a choice between a wafer served above a sample of ethanol and a wafer served above a sample of extract was given. The voles failed to habituate to the volatile components of extract, consistently consuming less of the wafers served above extract. In Experiment 3 a dose‐response curve to Zanthoxylum extract was established, using 12 stimulus‐naïve voles. After baseline consumption was established, the animals were given two tests each, presenting a choice between a control wafer and a wafer dipped in a dilution of extract (0.001–100 g liter?1). Only concentrations of 10 and 100 g liter?1 reduced food intake. In Experiment 4 the effects of the non‐volatile fraction of extract were compared to those of whole extract. Vegetable oil was used as solvent. Eight stimulus‐naïve voles were given two tests with a choice between an oil‐dipped and an extract‐dipped wafer. A second group of eight voles received two tests with a choice between an oil‐dipped and NVA‐dipped wafer. Extract‐dipped wafers were avoided, but the NVA fraction had no effect on food consumption. Copyright © 2004 Society of Chemical Industry  相似文献   
90.
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