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171.
Goats were experimentally infected with Trypanosoma congolense and then treated with Berenil after 9 days of infection. The infection produced increases in glutamate oxalacetate transaminase (GOT) and glutamate pyruvic transaminase (GPT) values. Mean GOT values in infected West African dwarf goats were generally lower than in infected Red Sokoto goats. Treatment with Berenil did not produce any significant effect on their levels probably because of the relapse infection recorded in this study.  相似文献   
172.
Ophthalmic examination findings in adult pygmy goats (Capra hicus)   总被引:1,自引:1,他引:0  
Objective To document normal ophthalmic findings and ocular abnormalities in captive adult pygmy goats. Animals studied Ten healthy adult pygmy goats (five male, five female; 5–11 years of age; 26–45 kg body mass) underwent complete ophthalmic examinations. Procedure Direct illumination, diffuse and slit‐beam biomicroscopy, indirect ophthalmoscopy, IOP measurements and Schirmer tear tests were performed. TonoVet® rebound tonometry, followed by topical application of 0.5% ophthalmic proparacaine, and Tono‐Pen XL® applanation tonometry were performed in each eye to obtain estimates of IOP. Results Ophthalmic abnormalities included corneal scars and pigmentation, incipient cataracts, lenticular sclerosis, and vitreal veiling. Mean STT values were 15.8 mm/min, with a range of 10–30 mm/min. Mean IOP values were 11.8 mmHg for TonoVet®‐D, with a range of 9–14 mmHg; 7.9 mmHg for TonoVet®‐P, with a range of 6–12 mmHg; and 10.8 mmHg for Tono‐Pen XL®, with a range of 8–14 mmHg. Conclusions Ophthalmic examination findings in adult pygmy goats, including normal means and ranges for STT and IOP measurements, using applanation and rebound tonometry, are provided.  相似文献   
173.
An 11-year-old, spayed female giant schnauzer was presented for evaluation of chronic, progressive tetraparesis. Diagnostic imaging was consistent with intervertebral disk protrusion, and surgical decompression and stabilization were performed. Postoperatively the dog did not improve, and further imaging suggested an intramedullary mass at the level of the sixth cervical vertebra. The dog was euthanized 7 days after surgery, and a teratoma was found postmortem.  相似文献   
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Nuisance odors generation from waste and wastewater treatment plants are a cause of public discomfort and complaints. This situation impairs the air quality and represents a growing social and public health problem, especially in developing countries. Several modeling approaches have been developed and successfully implemented in the frame of a wastewater treatment plant for both the biological treatment and physicochemical processes. The mathematical modeling of the odor generation process is still considered a quite complex issue, mainly due to the fact that olfactory nuisance can be caused by many different chemical compounds and the perception of odors is influenced by subjective thresholds. Moreover, the impact of odor sources on air quality is highly conditioned by complex atmospheric dispersion processes. This review presents a critical state-of-art and assessment where information related to odor emissions impact studies as well as modeling applications are compiled and discussed.  相似文献   
177.
Coffee has been an important and heavily used beverage in many cultures over a long period of time. Although sulfur species have been found to be abundant constituents, no work to date has explored the presence of selenium analogues. Investigation of volatile selenium species from green coffee beans, roasted beans, and brewed coffee drink was performed using solid phase microextraction (SPME) sample preconcentration in conjunction with GC/ICP-MS. Several volatile selenium species at trace levels were detected from roasted coffee beans as well as in the steam from brewed coffee drinks. No detectable selenium (and sulfur) species, however, were found in the headspace of green beans, indicating that selenium-containing volatiles are formed during roasting, as is the case for the sulfur volatiles. Matching standards were prepared and used to identify the compounds found in coffee. Artificial supplementation of the green coffee beans with selenium before roasting was performed to further characterize the selenium-containing volatiles formed during the coffee-roasting process.  相似文献   
178.
Biotic homogenization, driven by native species losses and invasive species gains was investigated for the flora of California. Data from a variety of available databases were aggregated at the county level to examine patterns in county population density and growth in relation to floristic change. Based on population, California was divided into three zones: high (n = 9; 257-1320 people/km2), medium (n = 25; 28-177 people/km2), and low (n = 24; 1-24 people/km2) density counties. Examining patterns of rare plant occurrences among these counties revealed that high and medium density counties contained, on average, as many or more rare and endemic species than low density counties. The largest pool of these species, 48 percent of the 962 highly threatened taxa in California, is restricted to high and medium density counties. Thus, urban and urbanizing counties play a strategic role in maintaining a part of California’s flora that is both globally significant and threatened with extinction. Examining species losses and noxious weed additions across high density counties, reveals a consistent pattern of low similarity among species that have been extirpated from high density counties and a high similarity among noxious weeds that these counties now share. The consequence is that California’s urban county floras appear to be homogenizing. Examining homogenization using the entire flora for urban counties demonstrates that less similar counties become more similar. The effect of loss of rare species could outweigh the gain in exotics, under an assumption of strong extinction. Finally, a strong negative relationship between population density and the proportion of county land in public ownership suggests that high and medium density counties are in a poor position to protect rare plant populations on a localized basis.  相似文献   
179.
Landscape Ecology - Network-theoretic tools contribute to understanding real-world system dynamics, such as species survival or spread. Network visualization helps illustrate structural...  相似文献   
180.
A combination of social surveys and direct field observations was used to identify and enumerate the tree species that are presently planted in and around the urban centers in the three zones of Ekiti State, Nigeria. A total of 62 tree species belonging to 27 families were sampled as urban tree species in the study area. Products derived from these trees ranged from edible fruits, cash income, medicine, fuel, shade, and wind control. The various similarity measures revealed that similar species of trees occurred as urban tree species in the three zones of the study area. Interviews with the various respondents revealed that all of them were tree minded irrespective of their sex, age, educational, economic, and religious status. Thus, these features were not regarded as prerequisites to tree mindedness in the study area. Field observation revealed that urban forestry is still poor in the state and at present the products derivable from the trees influenced the choice of species planted by the respondents. Thus, the various advantages derivable from the urban tree species, coupled with the tree mindedness of the respondents, could be utilized to serve as viable incentives to tree cultivation—especially in Nigeria where previous efforts had concentrated on farm and industrial forestry.  相似文献   
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