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排序方式: 共有387条查询结果,搜索用时 15 毫秒
301.
302.
Treatments in big sagebrush (Artemisia tridentata Nutt.) are often implemented to improve habitat conditions for species such as greater sage-grouse (Centrocercus urophasianus). These treatments aim to increase the availability of forbs and invertebrates critical to juvenile and adult sage-grouse during the breeding season. However, information regarding the response of forbs in treated sagebrush are often conflicting, dependent on the type of sagebrush community treated and time after treatment. In addition, there is little information on the response of invertebrates to treatments, particularly herbicide treatments in Wyoming big sagebrush (A.t. ssp. wyomingensis Beetle & Young) communities. We evaluated the response of forbs and invertebrates in Wyoming big sagebrush that had been mowed or aerially treated with tebuthiuron compared with untreated reference areas. We also compared forb and invertebrate dry matter (DM) between treated plots and locations used by brood-rearing females. Forb and invertebrate DM in mowed and tebuthiuron treatments did not differ from untreated plots up to 4 yr after treatment and were equal to or less than locations used by brood-rearing grouse up to 2 yr after treatment. Our findings corroborate best available science that suggest treating Wyoming big sagebrush may not increase food availability for sage-grouse. 相似文献
303.
AC Morini NCG Pieri KCS Roballo DS Martins CE Ambrósio JC Morini Junior PO Favaron AHH Minervino FVT Pereira MA Miglino 《Reproduction in domestic animals》2016,51(4):509-514
Many researches describe the embryonic developmental features in domestic animals; however, in farm animals, they are scarce. Most farm animal studies are related to assisted reproduction and embryos transfer techniques. But, morphological features and size measure to estimate the age gestation are rarely reported in literature. Thus, in this study, we described the developmental changes in the bubaline (Bubalus bubali) concepts from 21 to 60 days of gestation. Our results revealed that buffalo embryos similar morphological characteristics similar to other mammalian species. Also, similarities between bovine and bubaline persist; except on foetal stages when buffalos have a faster development than bovine. Therefore, buffalo's gestation period exhibits some varieties and accurate embryo age is more difficult. Yet, when we use a combination of the crown–rump, macroscopic analysis and alizarin red, it is possible to describe better the whole embryogenesis stages of the buffalo and which can contribute for future reproduction researches and applications in veterinary practice. 相似文献
304.
Dorothy A. Walther Gerald J. Ramelow James N. Beck John C. Young James D. Callahan Michael F. Marcon 《Water, air, and soil pollution》1990,50(3-4):279-292
The lichens Ramalina stenospora and Parmotrema praesorediosum were collected from 30 stations in the greater metropolitan area of Baton Rouge, Louisiana and analyzed for Al, Cu, Fe, Zn, and Pb content. A univariate analysis of the data showed a significant difference between metal concentrations and sampling stations. When the stations were separated into two groups representing those in the industrial and urban zones, a discriminant analysis was over 90% successful in correctly assigning stations based solely on metal concentrations. No significant differences in metal concentration with species could be observed. Average metal concentrations for the two lichen species were used to construct contours and three-dimensional plots of metal distribution across the study area which clearly demonstrate the effects of the industrial zone on airborne metal levels. 相似文献
305.
Barrs VR Nicoll RG Churcher RK Beck JA Beatty JA 《The Journal of small animal practice》2007,48(8):449-454
OBJECTIVES: To review the literature on intracranial empyema and report two new cases in cats. METHODS: Literature review and case reports. RESULTS: Intracranial empyema has been rarely reported in small animals. In two novel cases in cats, the route of infection was postulated to be local extension from a retrobulbar abscess of odontogenic origin in one case and direct inoculation from a penetrating bite wound to the skull, confirmed at post-mortem examination, in the other. On magnetic resonance imaging of the first case, there was a contrast-enhancing large extra-axial fluid collection overlying the right cerebral hemisphere, consistent with subdural empyema. Infection was caused by an Actinomyces spp. This is the first report of successful treatment of intracranial empyema by craniotomy, drainage and antibiotics. CLINICAL SIGNIFICANCE: Intracranial empyema is a neurosurgical emergency. Favourable outcomes may be achieved with surgical decompression, antimicrobial therapy and intensive care. 相似文献
306.
K. Nckler A. Hamidi R. Fries J. Heidrich R. Beck A. Marinculic 《Zoonoses and public health》2004,51(6):297-301
A total of 1401 German and 226 Croatian pigs raised either indoors or outdoors were tested for Trichinella infection by direct and indirect detection methods. A 10 g sample of diaphragm were examined for muscle larvae by the artificial digestion method; the species was determined by multiplex polymerase chain reaction (PCR). For detection of anti‐Trichinella IgG, serum samples diluted 1:100, and meat juice samples diluted 1:10, were tested by enzyme‐linked immunosorbent assay. All German pigs and those Croatian pigs raised indoors proved to be Trichinella‐negative by all methods. Muscle larvae were detected in a total of eleven of the Croatian pigs, which were raised on small outdoor farms. For eight isolates, PCR results demonstrated that recovered larvae were Trichinella spiralis. Anti‐Trichinella‐IgG was detected in serum and meat juice of digestion positive animals when the worm burdens exceeded 0.38 larvae per gram of muscle. Positive results in Croatian pigs indicate a higher risk of infection for outdoor farming in areas where Trichinella is endemic. Results of direct and indirect detection were compared and are discussed with special regard to specificity and sensitivity of methods. 相似文献
307.
OBJECTIVE: To evaluate combination therapy with azathioprine and metronidazole in German Shepherd Dogs with perianal fistulae. DESIGN: Prospective study. PROCEDURE: Five dogs (31.5 to 36.0 kg) with perianal fistulae were treated with azathioprine (50 mg per dog orally every 24 h) and metronidazole (400 mg per dog orally every 24 h). Patients were re-evaluated at 2 week intervals by inspection, palpation, photographs of the perineal region and assessment of white blood cell counts where possible. Treatment was continued until improvement in lesions reached a plateau. Surgical excision of residual fistulae and anal sac remnants was then performed, with medical therapy continued for an additional 3 to 6 weeks. RESULT: Signs attributable to anal irritation were reduced or eliminated in all dogs within 2 weeks, although visible healing of lesions progressed more slowly. Ulcerated lesions reduced in surface area and depth, and some fistulae healed completely. Non-healing areas were usually associated with anal sac rupture or chronic fibrosis. Visible improvement typically reached a plateau 4 to 6 weeks after commencing treatment. Immunosuppressive therapy continued for 5 to 24 weeks before surgical intervention to remove anal sacs (four dogs) and/or residual fistulae (five dogs). All dogs remain disease free 7 to 10 months postoperatively. No important complications of treatment were encountered. CONCLUSION: Azathioprine with metronidazole effectively reduced perianal irritation, and the severity and extent of lesions prior to surgery. Treatment was economical even in large dogs and associated with few untoward sequelae. The combined use of immunosuppressive and antimicrobial therapy followed by surgery minimised potential morbidity associated with aggressive use of either medical of surgical treatment alone. 相似文献
308.
309.
S Fuchs T Beck S Burkardt M Sandvoss A Mosandl 《Journal of agricultural and food chemistry》1999,47(8):3053-3057
Pulegone, menthone, and isomenthone isotopomers are synthesized as regioselectively deuterated d(5)- and d(8)-stereoisomers. Deuterium-labeled menthone and isomenthone enantiomers are analyzed using enantioselective multidimensional gas chromatography/mass spectrometry. The deuterated stereoisomers of menthone and isomenthone are separated from the unlabeled menthone and isomenthone on a glass capillary column, coated with 50% octakis(2, 3-di-O-butyryl-6-O-tert- butyldimethylsilyl)-gamma-cyclodextrin in OV 1701vi as the chiral stationary phase. These deuterium-labeled monoterpene ketones are proved to be highly valuable substrates in biosynthetic studies of terpenoid compounds. 相似文献
310.
Mentha x piperita shoot tips and first leaf pair were fed with aqueous solutions of [(2)H(2)]- and [(2)H(2)]/[(18)O]-labeled pulegone. The essential oil was analyzed by solid phase microextraction and enantioselective multidimensional gas chromatography/mass spectrometry. After feeding experiments with labeled pulegone racemate, both labeled (S)-menthofuran and (R)-menthofuran were detectable simultaneously together with genuine (R)-menthofuran. It could be shown that both labeled pulegone enantiomers are converted by Mentha x piperita to the corresponding labeled menthofuran enantiomers, favoring the labeled analogue of the nongenuine (S)-pulegone. The oxygen in menthofuran is introduced by enzymatic oxidation of pulegone, as concluded from feeding experiments with mixed labeled [(2)H(2)]/[(18)O]pulegone. 相似文献