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排序方式： 共有517条查询结果，搜索用时 15 毫秒
1.
Ernst Knippel Röhrl Schüpster Schaile und Fabricius 《Forstwissenschaftliches Centralblatt》1927,49(19):687-703
Ohne Zusammenfassung 相似文献
2.
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
3.
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
4.
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
5.
Pablo M. Vergara Luis O. Meneses Audrey A. Grez Madelaine S. Quiroz Gerardo E. Soto Christian G. Pérez-Hernández Paola A. Diaz Ingo J. Hahn Andrés Fierro 《Landscape Ecology》2017,32(2):279-293
Context
Interactions between landscape-scale processes and fine-grained habitat heterogeneity are usually invoked to explain species occupancy in fragmented landscapes. In variegated landscapes, however, organisms face continuous variation in micro-habitat features, which makes necessary to consider ecologically meaningful estimates of habitat quality at different spatial scales.Objectives
We evaluated the spatial scales at which forest cover and tree quality make the greatest contribution to the occupancy of the long-horned beetle Microplophorus magellanicus (Coleoptera: Cerambycidae) in a variegated forest landscape.Methods
We used averaged data of tree quality (as derived from remote sensing estimates of the decay stage of single trees) and spatially independent pheromone-baited traps to model the occurrence probability as a function of multiple cross-scale combinations between forest cover and tree quality (with scales ranging between 50 and 400 m).Results
Model support and performance increased monotonically with the increasing scale at which tree quality was measured. Forest cover was not significant, and did not exhibit scale-specific effects on the occurrence probability of M. magellanicus. The interactive effect between tree quality and forest cover was stronger than the independent (additive) effects of tree quality and particularly forest cover. Significant interactions included tree quality measured at spatial scales ≥200 m, but cross-scale interactions occurred only in four of the seven best-supported models.Conclusions
M. magellanicus respond to the high-quality trees available in the landscape rather than to the amount of forest per se. Conservation of viable metapopulations of M. magellanicus should consider the quality of trees at spatial scales >200 m.6.
China has taken a foreign direct investment‐based approach toward increasing its capital and knowledge base, and developing into an innovative economy. However, little quantitative evidence exists about the factors that drive innovations of foreign‐invested enterprises (FIEs) there. This paper uses survey data from high‐technology firms in Shanghai to discuss factors affecting their innovativeness. It takes the concepts of absorptive capacity, export orientation, and innovation‐related cooperation as a starting point. It highlights how the interplay of strategies and resources affects innovativeness and heterogeneity of FIEs. The most innovative FIEs are endowed with a strong human capital base and R&D activities, which at the same time target export markets and whose cooperative partners involve firms other than their parent company. The results underline the necessity to differentiate between the different types of FIEs when examining their innovativeness. 相似文献
7.
8.
Gervers M Nolte I Alt F Hauschild G Meyer-Lindenberg A Fehr M 《Berliner und Münchener tier?rztliche Wochenschrift》2002,115(11-12):412-419
164 total hip prostheses of different manufacturers were implanted over an 8-year period. Clinical records were evaluated with a complication rate of 29.0% (42 of 145 joints) or 31.7% (39 of 123 dogs). The complications encountered in dogs that received the modular hip prosthesis (Biomécanique, Bretigny-sur-orge, France) amounted to 16.3% (15 of 92), dogs that received a fixed head prosthesis (5 different manufactures) had 39% complications (28 of 72). Although the complication rate was influenced by different surgeons (n = 5) with different system predelictions and a different learning curve it was obvious that luxations (n = 6 of 10) and stem fractures (n = 5) more often occurred with the fixed head prosthesis systems. These stem fractures might be due to implant material failure or due to improper cementation followed by fatigue material failure. Femur fracture or infection were encountered with both prosthesis systems. 相似文献
9.
10.
Fabricius Fritz Ernst Reinhold Haenel und Bogtherr 《Forstwissenschaftliches Centralblatt》1933,55(21):758-770
Ohne Zusammenfassung 相似文献