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921.
Lymphocyte beta -adrenoceptor downregulation in great danes with occult dilated cardiomyopathy (DCM) and with DCM and heart failure. 总被引:2,自引:0,他引:2
M Borgarelli P Badino L Bergamasco C Bussadori R Odore G Re A Tarducci U Dotta 《Veterinary journal (London, England : 1997)》1999,158(2):128-134
The importance of the adrenergic nervous system in supporting the failing heart has long been known. The adrenergic drive on cardiac structure and function has however some adverse effects, which include myocardial beta-adrenoceptor (beta-AR) downregulation and decreased beta-adrenergic responsiveness to cathecolamines. In dog lymphocytes, beta(1)-AR and beta(2)-AR populations are almost equally represented (with a slight prevalence of beta(2)) and a significant correlation between cardiac and lymphocytic adrenoceptors has been found. The aim of the present study was to investigate possible differences between the concentration of lymphocytic beta-AR in healthy dogs, dogs with dilated cardiomyopathy (DCM) and dogs with occult DCM. Three groups of great danes were considered: a control group (n =10), dogs with DCM (n =9) and dogs with occult DCM (n =4). Lymphocytic beta-AR populations were determined in all dogs. A substantial and significant decrease (P<0.05) in total-AR, beta(1)-AR and beta(2)-AR concentrations in the lymphocytes of dogs with symptomatic DCM and occult DCM compared to the control group was found. Although the mean value of the lymphocyte beta(1)-AR number in the asymptomatic group was double compared to the DCM group, this difference was not statistically significant. We conclude that in dogs beta-AR downregulation occurs early in the course of dilated cardiomyopathy. This finding may suggest the value of early use of a beta-blocker in the therapeutic regimen. Moreover, the continuous monitoring of lymphocytic beta-AR may represent a useful tool for the development of a more effective individual therapy. 相似文献
922.
Test of size-specific mass selection for Nile tilapia, Oreochromis niloticus L., cage farming in the Philippines 总被引:1,自引:0,他引:1
One generation of mass selection based on the collimation procedure (early culling of large fry) was applied on Nile tilapia, Oreochromis niloticus L., in net cages set in Laguna de Bay, Philippines. The objective was to test the effectiveness of a low-cost, small-scale broodstock improvement procedure in this culture environment. Directional selection was performed in two steps after initial removal of large fry at 21 days. Selection of parents and testing of the offspring were also conducted in hapa net cages set up in Laguna de Bay. The selection resulted in a significant positive response of 3% relative to the control, which represents a projected 34% gain over 5 years in Laguna cage culture. The realized heritability is ≈16%. 相似文献
923.
Rabbits infected with Trypanosoma brucei brucei (Basa isolate) were intraperitoneally administered with vitamins C and E at 100 mg/kg and 10 mg/kg body weight, respectively, from day 7 before infection to day 12 post-infection (p.i.). Another group of rabbits were similarly infected, but received no vitamin treatment. The uninfected (control) rabbits were either untreated or treated with vitamins like the infected group. Treatment of the infected animals did not affect the onset and level of parasitaemia. On day 12 p.i., the anaemia tended to be ameliorated, but insignificantly, by the treatment. The infection increased (p<0.05) serum urea and creatinine concentrations to similar levels in treated and untreated groups. However, the increase (p<0.05) in alanine and aspartate transaminases in the untreated infected animals was prevented in the treated infected ones. Therefore, it seemed that the treatment with antioxidant vitamins boosted their storage in hepatic cells, but not in erythrocytes and glomeruli, to annul any cellular injury due to infection. It is concluded that this may be an indirect evidence that the hepatic damage may be principally due to oxidative injury. 相似文献
924.
U Braun U Estermann K Feige T Sydler A Pospischil 《Journal of the American Veterinary Medical Association》1999,215(5):679-681
OBJECTIVE: To determine safety of lung biopsy in healthy cattle and compare 3 biopsy instruments for suitability of use. DESIGN: Prospective study. ANIMALS: 60 healthy cows. PROCEDURE: Bilateral lung biopsy through the ninth intercostal space was attempted in all cows. The procedure was performed with cows standing and restrained by an assistant. To study the short-term effects of lung biopsy, 50 cows were slaughtered 1 day after the procedure and examined. To study the long-term effects of lung biopsy, the remaining 10 cows were examined daily for 10 days and then slaughtered. Three biopsy instruments--the Autovac biopsy cannula, the Tru-Cut needle, and the Bard Biopty-System--were evaluated. RESULTS: 2 cows collapsed momentarily during the procedure but recovered quickly. The remaining cows did not develop adverse effects, and general attitude and condition were not affected. Postmortem examination of the 50 cows slaughtered 1 day after the procedure revealed lesions < or = 5.0 mm long and with a surface area < or = 4.0 mm2 at 108 of 154 (71%) biopsy sites involving the pulmonary pleura. Biopsy specimens were obtained during 48 of 50 (96%) procedures in which the Tru-Cut needle was used, during 38 of 39 (97%) procedures in which the Bard Biopty-System was used, and during only 1 of 11 biopsy procedures in which the Autovac cannula was used. At postmortem examination of the 10 cows slaughtered 10 days after the procedure, lesions were seen as small scars; adhesions were not observed. CONCLUSIONS AND CLINICAL RELEVANCE: Percutaneous lung biopsy is a safe procedure in healthy cows. 相似文献
925.
Emergence and recent evolution of canine parvovirus. 总被引:6,自引:0,他引:6
U Truyen 《Veterinary microbiology》1999,69(1-2):47-50
This review summarizes the current knowledge about the emergence of canine parvovirus from an ancestor virus similar to feline panleukopenia virus most likely from a wild carnivore host. The recent evolution of CPV, namely the emergence of new antigenic types, their biological properties and global distribution are also discussed. 相似文献
926.
实验利用鸭全血中单核细胞,粒细胞,血栓细胞及自然杀伤细胞对酵母细胞非特异性细胞毒性作用,检测了15日龄鸭胚到112日龄鸭非特异性细胞免疫的发生。实验结果表明,鸭胚孵出前1周的22日龄到孵出后3日龄是鸭非特异性细胞免疫的发生期;3 ̄112日龄鸭在正常的生理状态下非特异性细胞免疫水平没有明显的变化。 相似文献
927.
S Burkhardt J Hentschke H Weiler B Ehlers A Ochs J Walter U Wittstatt R G?ltenboth 《Berliner und Münchener tier?rztliche Wochenschrift》1999,112(5):174-179
Herpesvirus infections which take a fatal turn on African elephants as well as on Asian elephants seem to occur increasingly not only in the USA but also in European stocks. The endotheliotropic herpesvirus causes a rapidly progressing and severe disease which makes any therapeutical effort unsuccessful and finally results in death of the animal, especially in young Asian elephants. As all attempts to culture the virus failed up to now, molecular biological procedures have to be used more often for diagnostical purpose together with the common methods of pathology, virology, and electronmicroscopical evaluation. This is a report on the case of 'KIBA', an eleven year old male elephant at the Zoological Garden Berlin, infected with the endotheliotropic elephants herpesvirus. 'KIBA' was born at the Zoo in Houston, Texas, and raised within his herd. Upon arriving in Berlin in November 1997 he adapted to the new premises and climate and new social circumstances without any problems. In June 1998 he already serviced three females of his new herd several times. In August 1998 he died after passing a peracute progression of the disease after residenting in Berlin for only 9 months. The dissection of the animal revealed some evidence on an agent damaging the endothelium. Major signs indicating this agent were bleedings in several serous membranes, mucosa and on the the right atrium, as well as other parts of the myocardium. Furthermore there have been ulcerations at various localisations of the whole digestive tract. Slightly basophilic intranuclear inclusion bodies have been found histologically in endothelial cells of different organ samples. An examination of altered organ-material by electronmicroscopy made some herpesvirus-like particles visible. A virological investigation first revealed evidence of giant cell formations with solitary basophilic intranuclear inclusion bodies in different cell cultures, however, without any distinct cytopathogenic effect. Supported by molecular biological procedures the infection of 'KIBA' could be verified as the elephants herpesvirus. By means of PCR and subsequent sequence analysis a DNA-sequence typical for the elephants herpesvirus could be obtained which showed an identity of 97% with the terminase sequence of the elephant herpesvirus described by American authors. The deduced amino acid-sequences were 100% identical. To the terminase of the human cytomegalovirus, the elephant sequence had an identity of 53% (similarity: 74%). Based on the cooperation of ILAT, Institute of Veterinary-Pathology/Free University Berlin, Robert-Koch-Institut Berlin, and Zoological Garden Berlin, the cause of 'KIBA's' death could be discovered immediately. Possible implications of this case especially on breeding and keeping elephants are discussed briefly. 相似文献
928.
An unusual case of primary fibrosarcoma of the liver in a cow is described. The most prominent pathological findings were severe abdominal haemorrhage and neoplastic masses confined to the liver only. Histologically, spindeloid cells arranged in interlacing bundles running in various directions and numerous areas of necrosis and ossification were randomly scattered in the neoplasm. 相似文献
929.
M Hertel U Kersten R Mischke I Nolte 《Berliner und Münchener tier?rztliche Wochenschrift》1999,112(6-7):239-242
Based on results of holter ecg recordings taken from 38 dogs the computerized analyses system turned out as method not exactly valuing the frequency and sensitivity of arrhythmias. Despite there was a significant correlation between the computerized and visual arrhythmia analysis for ventricular respectively supraventricular premature beats, in individual cases there was an important aberration between the particular values. 相似文献
930.
1. Growth of the oesophagus, proventriculus, gizzard, intestine, liver and pancreas weight was investigated in Mallards, White Pekins, Muscovies and a Muscovy x White Pekin cross. The birds varied in age between hatching and 154 d. The data were analysed by fitting both the Janoschek growth curve and the allometric formula. 2. The growth rate of all organs, except the oesophagus, peaked earlier (30 d for Muscovies and 14 d for the other breeds) than body weight and they grew faster to any given percentage of their final weight. In contrast, oesophagus weight showed growth curve characteristics similar to body weight. 3. Oesophagus weight showed simple, slightly negative allometry. The remaining organs followed complex allometry that can approximately be described by 2 allometric stages. The 1st phase was isometric to positive allometric. The 2nd showed marked negative allometry. 4. These growth patterns are assumed to be generally present in birds. 相似文献