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排序方式: 共有885条查询结果,搜索用时 155 毫秒
91.
This study concerns the vestigial metacarpal and metatarsal bones, so called splint bones. The soft tissues, which stabilize the splint bones were carefully examined. The palmar metacarpal/plantar metatarsal fascia, the metacarpal/metatarsal interosseous ligaments and the fibres, which exit distally from the splint bone, were examined in depth. Cadaveric distal limbs were collected from 5 slaughtered or euthanized horses. The legs were examined both, microscopically and macroscopically. The palmar metacarpal/plantar metatarsal fascia is a very stable structure, which connects the splint bone with its environment. The connection between splint and McIII/MtIII, established through the metacarpal/ metatarsal interosseous ligaments, showed impressive differences between specimens examined. Macroscopic examination of the soft tissue in the distal region showed a band structure, which originates from the distal end of the splint bone and extends in dorsal and distal direction towards the proximal sesamoid bone. 相似文献
92.
93.
Bleul UT Schwantag SC Bachofner C Hässig MR Kähn WK 《Journal of the American Veterinary Medical Association》2005,226(7):1119-1123
OBJECTIVE: To determine milk flow, somatic cell counts (SCCs), and the incidence of clinical mastitis in cows that had undergone theloresectoscopy for treatment of teat stenosis caused by mucosal detachment in the region of the streak canal or Fürstenberg's rosette. DESIGN: Retrospective study. ANIMALS: 52 cows with teat stenosis that were treated via theloresectoscopy. PROCEDURE: Medical records of eligible cows were reviewed. Additional data regarding milking ease, SCC, development of clinical mastitis of the affected gland, and whether the cow remained in the herd were collected via owner-completed questionnaires. RESULTS: 49 of 52 questionnaires were completed. At referral, teat sinusitis was diagnosed in 29 of 52 cows. Milk flow was normal in 38 of 41 treated teats at discharge and in 24 of 40 during the next lactation. Thirteen of 49 cows were culled during the next lactation because of abnormal udder health. High SCC and teat sinusitis at referral and development of clinical mastitis during the 10-day period after surgery resulted in high SCCs in the remainder of the current lactation. The incidence of clinical mastitis during the remainder of the current and during the next lactation was higher in cows that had teat sinusitis at the time of surgery, compared with those that did not. CONCLUSIONS AND CLINICAL RELEVANCE: Teat stenoses resulting from mucosal lesions in the region of the streak canal or Fürstenberg's rosette may be successfully treated via theloresectoscopy. Inflammation of the teat sinus and gland at the time of surgery may adversely affect udder health. 相似文献
94.
Steffan J Parks C Seewald W;North American Veterinary Dermatology Cyclosporine Study Group 《Journal of the American Veterinary Medical Association》2005,226(11):1855-1863
OBJECTIVE: To determine efficacy and safety of cyclosporine in the treatment of atopic dermatitis among dogs in North America. DESIGN: Randomized controlled (phase 1) and open-label (phase 2) trials. ANIMALS: 268 dogs with atopic dermatitis. PROCEDURE: In phase 1, dogs were randomly assigned to be treated with cyclosporine (5 mg/kg [2.3 mg/Ib], PO, q 24 h) or a placebo. In phase 2, all dogs were treated with cyclosporine for 16 weeks. Frequency of cyclosporine administration was decreased if dogs improved clinically. RESULTS: At the end of phase 1, canine atopic dermatitis extent and severity index (CADESI) scores for dogs treated with cyclosporine were significantly lower than scores for control dogs. Percentage of dogs with severe pruritus decreased from 67% to 16% for the cyclosporine group but from 66% to only 61% for the control group. During phase 2, cyclosporine dosage was decreased to every-other-day administration in 39% of the dogs after 4 weeks. After 12 weeks, 22% of the dogs were treated twice weekly and 36% were treated every other day. After 16 weeks, CADESI score had decreased > 50% in 68% of the dogs and 47% of dogs had no or mild pruritus. The most frequent adverse reactions were gastrointestinal tract signs. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that cyclosporine is efficacious for the treatment of atopic dermatitis in dogs and that frequency of cyclosporine administration can be reduced following an initial induction period. The drug was well tolerated. 相似文献
95.
Kauffold J Amer HA Bergfeld U Weber W Sobiraj A 《The Journal of reproduction and development》2005,51(3):325-332
This study investigated the relationship between follicle size (FS) and developmental competence of calf oocytes. Cumulus-oocyte-complexes (COCs) from follicles>8 (L-COCs; n=19), 4-8 (M-COCs; n=54), and 2-3 mm (S-COCs; n=155) were recovered from non-stimulated 1-4 months old dairy calves post mortem and ex vivo (laparoscopy), and in parallel from slaughtered adult cows from follicles of identical size categories [>8 (n=91); 4-8 (n=138); 2-3 mm (n=193)]. Morphologically intact COCs were subjected to in vitro maturation, fertilization, and embryo culture. Cleavage rate (CR; 46 h post-insemination=p.i.), rate of morulae/blastocysts (M/Bl; day 7 p.i.), and blastocysts (Bl; day 9 p.i.) were recorded. FS had no effect on the CR in calves. However, calf L-COCs yielded the highest rates of M/Bl and Bl compared with the two other size categories (P<0.05). In contrast, calf S- and M-COCs gave similar rates of M/Bl, whereas the proportion of Bl was lowest for S-COCs (P<0.05). This was almost identical to findings in cows, except that the CR was highest for L-COCs and M/Bl yields were lowest for S-COCs (P<0.05). There were no differences between calf and cows with regard to CR for the respective FS categories. L-COCs from calves and cows yielded similar rates of M/Bl and Bl, whereas calf S- and M-COCs yielded lower rates of Bl than S- and M-COCs from cows and a lower rate of M/Bl when S-and M-COCs were analyzed as one group (P<0.05). Whereas the CR was similar in calves and cows, calf COCs yielded lower rates of M/Bl and Bl (P<0.05). In conclusion, the results show that the developmental competence of calf oocytes is higher in those derived from follicles larger than 8 mm, and thus are almost equally as competent as cow oocytes derived from follicles of identical size. This suggests that calf oocytes acquire developmental competence within the large follicle, potentially due to a process similar to prematuration of the oocyte in the adult cow. It is proposed that procedures that facilitate prematuration, such as "coasting" following a preceding superstimulation, might increase the developmental competence of calf oocytes. 相似文献
96.
Zusammenfassung Gefäßkulturen von Hafer in Sand und Erde mit abgestuftem, jeweils gleichbleibend gehaltenem Wasserangebot von 100, 75, 50, 30 und 15% der Boden wasserkapazität ergaben die höchsten Erträge an Gesamttrockenmasse in der Regel bei voller Wassersättigung des Bodens in Verbindung mit gleichzeitig maximalem Wasserverbrauch (bestimmt durch tägliches Wägen der Gefäße). Abnehmende Wasserversorgung verringerte auch Trockenmasse und Wasserverbrauch der Pflanzen. In trockenem Boden und bei reichlicher Wasserzufuhr entwickelte sich die Wurzelmasse im Vergleich mit den oberirdischen Organen stärker als bei mittlerer Bodenfeuchtigkeit. Klimatische Einflüsse, Aussaatzeit und Witterung sowie die Bodenart modifizierten die vom Wasserzustand des Bodens ausgehenden Wirkungen auf Trockenmasseproduktion und Wasserverbrauch, z. B. wurde bei Sommeraussaat gegenüber der Frühjahrsaussaat die Blattentwicklung bedeutend gefördert.Mit registrierenden Infrarot-Gasanalysatoren wurden Tagesgänge von CO2-Aufnahme, Nachtatmung und Transpiration unter natürlichen Bedingungen gemessen. Bei trockenem Boden war die photosynthetische Leistung der Pflanzen zu Beginn ihrer Entwicklung deutlich gehemmt; sie steigerte sich allmählich und war später merklich größer als bei hohen Wassergaben. Die Transpiration verlief im allgemeinen gleichsinnig wie die Netto-Assimilationsrate, wurde jedoch auch nachts meist auf einer gewissen Höhe fortgesetzt. Die Nachtatmung der sehr trocken gehaltenen Pflanzen war gegenüber den anderen Wasserstufen meist erhöht. Die Trockenkulturen zeigten einen größeren Lichtbedarf; der Lichtkompensationspunkt wurde gewöhnlich erst bei höherer Beleuchtungsstärke erreicht als bei guter Wasserversorgung. Daraus wird auf erhöhten Energiebedarf der sehr trocken kultivierten Pflanzen geschlossen. Das Verhältnis zwischen CO2-Aufnahme und Transpiration wurde durch unterschiedliche Bodenwasserversorgung meist nur wenig beeinflußt. Die Ergebnisse der CO2-Assimilationsmessungen stehen im großen und ganzen mit dem wöchentlich festgestellten Trockensubstanzgewinn in Einklang.
Summary Cultures ofAvena sativa L. grown in pots with sand or garden soil with a graduated, in each case fairly constant water supply of 100, 75, 50, 30, and 15% of field capacity yielded maximum total dry weight, as a rule, in fully water-saturated soils combined with maximum water consumption (measured by daily weighing). Decreasing water supply reduced dry matter production and water consumption of plants. In dry soil and at high degrees of water saturation roots developed more dry matter in comparison to the shoots than at medium soil moisture. Results in dry matter production and water consumption, as caused by water relations in soil, are modified additionally by climatic factors, sowing date and weather, and soil type, e.g. sowing in summer considerably favoured leaf development, compared with the spring seed.Daily courses of CO2-uptake, night respiration and transpiration were registered by infrared-gasanalyzers. In very dry soil photosynthetic activity of plants was distinctly hampered during the first weeks of development; it gradually increased, and at a later stage photosynthetic activity was markedly higher than at abundant water supply. In general transpiration followed the net assimilation rate, it was continued, however, even over night on a certain level. Night respiration of plants growing in dry soil was higher in relation to the other water stages. Those plants, too, required more light for dry matter production; their light compensation point arrived at higher light intensity than under abundant water supply. This behaviour seems to indicate higher energy requirement of plants distinctly influenced by water stress. Relations between CO2-uptake and transpiration were but slightly influenced by different soil water level. Results of gas exchange measurements on CO2-assimilation agreed, as a rule, with the weekly dry matter measurements by weighting.
¶rt; 100, 75, 50, 30 15%. , , , ¶rt; ( ). , . ( ) , . , , ; . , . ( ) ( 2, ). ; , . , , , . , , , , . «» ; , . , , ¶rt;. 2 , , . 2 .相似文献
97.
98.
99.
Meinecke M Wagner R Kovermann P Guiard B Mick DU Hutu DP Voos W Truscott KN Chacinska A Pfanner N Rehling P 《Science (New York, N.Y.)》2006,312(5779):1523-1526
Transport of metabolites across the mitochondrial inner membrane is highly selective, thereby maintaining the electrochemical proton gradient that functions as the main driving force for cellular adenosine triphosphate synthesis. Mitochondria import many preproteins via the presequence translocase of the inner membrane. However, the reconstituted Tim23 protein constitutes a pore remaining mainly in its open form, a state that would be deleterious in organello. We found that the intermembrane space domain of Tim50 induced the Tim23 channel to close. Presequences overcame this effect and activated the channel for translocation. Thus, the hydrophilic cis domain of Tim50 maintains the permeability barrier of mitochondria by closing the translocation pore in a presequence-regulated manner. 相似文献
100.
Fürst A Kummer M Lischer C Bertolla R Auer J Geyer H 《Schweizer Archiv für Tierheilkunde》2006,148(2):55-63
Fifty-four horses with hoof cracks were referred to the Equine Hospital of the University of Zurich, for treatment. The horses were admitted because of lameness or other symptoms caused by the cracks. Deep or complicated quarter cracks were the most common type of cracks diagnosed. Poor conformation and abnormal hoof shape were the most important causes of hoof crack development, whereas injury to the coronary band was a less frequently encountered cause. Effective treatment of this problem includes corrective shoeing, removing horn from the weight-bearing surface as well as from the crack with a Dremel tool and immobilization of the borders of the crack. However, even with such a therapy, the recurrence rate of hoof cracks was with 20% very high. 相似文献