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排序方式: 共有676条查询结果,搜索用时 312 毫秒
1.
Martin Kramer Dr. Med. Vet Martin Gerwing Dr. Med. Vet Volker Hach Dr. Med. Vet Ernst Schimke Prof. Dr. Med. Vet 《Veterinary radiology & ultrasound》1997,38(2):139-149
Sonography of the musculoskeletal system in dogs and cats was undertaken to evaluate the application of this imaging procedure in orthopedics. In most of the patients a 7,5 MHz linear transducer was used because of its flat application surface and its resolving power. The evaluation of bone by sonography is limited, but sonography can provide addition information regarding the bone surface and surrounding soft tissue. Ultrasound is valuable for assessing joint disease. Joint effusion, thickening of the joint capsule and cartilage defects can be identified sonographically. It is also possible to detect bone destruction. Instabilities are often identified with the help of a dynamic examination. Soft tissue abnormalities of the musculoskeletal system lend themselves to sonographic evaluation. Partial or complete muscles or tendon tears are able to be differentiated and the healing process can be monitored. Most of the diseases that are in the area of the biceps or the achilles tendon, such as dislocation of the tendon, old injuries with scarification, free dissecates in the tendonsheath, tendinitis and/or tendosynovitis can be differentiated by sonography. In addition, with clinical and laboratory findings, it is often possible to make a correct diagnosis with ultrasound in patients with abscesses, foreign bodies, hematomas, soft tissue tumors and lipomas. 相似文献
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The technique of liver puncture as described by Holtenius (1961) was assessed with regard to its practicability and safety in a preliminary study of 26 cattle and a follow-up study of 108 German black pied cattle. The sample material was smeared, stained and examined by light microscope. All animals with changes of grade 5 had to be slaughtered. Liver puncture is a simple, quick and safe technique which supplies useful information about the various stages of hepatic fatty degeneration in individual cattle. 相似文献
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Current German law on animal rights requires protection and appropriate treatment of animals. However, information on breeding and raising swine is incomplete, and comparison studies of alternative housing systems are needed. Therefore, the effects of single and group housing of pregnant sows on piglet production was investigated in the 120-sow herd of the Institute for Animal Breeding and Husbandry of the University of Kiel. Reproductive traits, general health and behaviour studies were evaluated over one year. Type of housing system was found to have no effect on number of piglets born alive or dead or on days open. Daily gain was influenced. Daily gain of single-housed sows increased but without any difference in feed intake. General health was measured by nutritional condition, soiling, callosity, and injuries at time of evaluation. Single-housed sows had more calluses and were more soiled compared with group-housed sows. Injuries occurred more often in group housing, especially when new animals were integrated into the group. However, injuries were not serious. Animal behaviour was recorded on video during one pregnancy period of 60 sows. The housing system effected "sitting" and "lying" behaviour. Behaviour also is influenced by pregnancy in both housing systems. Equal incidences of abnormal behaviour, considered as sham-chewing, were found in both housing systems. 相似文献
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Shell aragonite from 96 specimens of the freshwater gastropod Limnaea stagnalis grown in laboratory tanks at different temperatures in water with variable strontium/calcium ratios have been analyzed for its strontium content in order to evaluate the mechanisms of strontium uptake in molluskan aragonite. Within the limits defined by natural freshwater environments, the strontium/calcium ratio in the aragonite was found to be linearly related to the strontium/calcium ratio in the water. A distribution coefficient k(A)(Sr) = 0.237 +/- 0.029, unaffected by variations in temperature and growth rate, has been found. This finding substantiates the existence of a strontium-discriminating effect in aragonite precipitated by mollusks as compared to the case for nonbiogenic aragonite which contains about five times as much strontium when precipitated under the same conditions. 相似文献
6.
Fritz Hervé Saïd Sonia Renaud Pierre-Cyril Mutake Snoden Coid Craig Monicat François 《Landscape Ecology》2003,18(3):293-302
After the eradication of the Tse-Tse fly in the Mid-Zambezi valley, human settlements and fields extended mainly along the main rivers. In order to investigate the consequences of this human development on wildlife diversity we monitored three rivers of the Mid-Zambezi valley in Zimbabwe: Angwa, Manyame and Kadzi. The rivers were divided in segments of 200 m which were checked for spoors in order to assess the number of species and the number of individuals that used the segments. Human settlements were also recorded. We used a GIS to define the spatial characteristics of the fields present along the rivers, and related them to the distribution and abundance of wild species spoors in the river beds and banks. Our results show that the number of species in one segment of the river decreased with the increasing size of the field area bordering the segment. For all the major ungulate species, the numbers of individuals recorded per segment decreased with increasing field area. A similar trend was observed for small and medium-sized carnivores, though they were in lower numbers when present. Our analyses thus confirm that the extension of human agriculture in wildlife areas has an impact on most wild species, but we also define some threshold value of field size above which there seem to be an acceleration of the decrease in wildlife density and diversity: 3.2 ha for medium and small herbivores and carnivores; only the elephant seem to tolerate larger field area with a threshold value of 32 ha.This revised version was published online in May 2005 with corrections to the Cover Date. 相似文献
7.
S. Narayanan P. V. V. Prasad A. K. Fritz D. L. Boyle B. S. Gill 《Journal of Agronomy and Crop Science》2015,201(3):206-218
High temperature is a major environmental factor that limits wheat (Triticum aestivum L.) productivity. Climate models predict greater increases in night‐time temperature than in daytime temperature. The objective of this research was to compare the effects of high daytime and high night‐time temperatures during anthesis on physiological (chlorophyll fluorescence, chlorophyll concentration, leaf level photosynthesis, and membrane damage), biochemical (reactive oxygen species (ROS) concentration and antioxidant capacity in leaves), growth and yield traits of wheat genotypes. Winter wheat genotypes (Ventnor and Karl 92) were grown at optimum temperatures (25/15 °C, maximum/minimum) until the onset of anthesis. Thereafter, plants were exposed to high night‐time (HN, 25/24 °C), high daytime (HD, 35/15 °C), high daytime and night‐time (HDN, 35/24 °C) or optimum temperatures for 7 days. Compared with optimum temperature, HN, HD and HDN increased ROS concentration and membrane damage and decreased antioxidant capacity, photochemical efficiency, leaf level photosynthesis, seed set, grain number and grain yield per spike. Impact of HN and HD was similar on all traits. Greater impact on seed set, grain number and grain yield per spike was observed at HDN compared with HN and HD. These results suggest that HN and HD during anthesis cause damage of a similar magnitude to winter wheat. 相似文献
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A. HüTtermann Marie-Therese Oelbe E. Fritz G. Schlechte A. Bytom A. D. Jungk Y. Okon E. Fallik Rivka Hadas S. Sarig E. Yahalom Sara Tal A. Hartmann B. Kishinevsky Debora Gurfel Rina Lobel Y. Kapulnik D. A. Phillips Y. Hadar Y. Chen E. Jurkevitch J. Katan A. Gamliel H. Ziegler I. Chet A. Ordentlich Hadar Kless A. Oppenheim Avia Zilberstein D. Holland J. Berman A. Zamir R. Kaufman N. Bawnik C. Koncz J. Schell 《Phytoparasitica》1987,15(2):141-147
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