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排序方式: 共有216条查询结果,搜索用时 280 毫秒
101.
Bjrn P. Berdal
rjan Olsvik Torbjrn Alrnlid Hans Jrgen Larsen Anne-Marie Lorentzen-Styr 《Acta veterinaria Scandinavica》1983,24(1):65
Toxoplasma gondii IgG antibodies were measured in 212 goat sera, comparing the Sabin-Feldman dye-test and a three-layer sandwich enzyme-linked immunosorbent assay (ELISA). With 98 % concordance obtained between these 2 tests, the results are at the same paragon as for human sera. Accordingly, the ELISA sandwich procedure appears to be suitable for large-scale analysis of goat sera. The discordant 2 % were ELISA positive and dye-test negative. One possible explanation of the divergent titres is given using an immunized goat model.Key words: Toxoplasma gondii, goat, antibodies, dye-test, ELISA 相似文献
102.
Susanne A.E.B. Boroffka DVM Anne-Marie J. Verbruggen DVM Michael H. Boevé DVM PhD Frans C. Stades DVM PhD 《Veterinary radiology & ultrasound》1998,39(5):440-444
Ultrasonography was performed on a Basset hound and a Doberman clinically suspected of persistent hyperplastic tunica vasculosa lentis/persistent hyperplastic primary vitreous. In both dogs, hyperechoic lenses with a triangular-shaped echodense structure retrolentally were visible, and a very thin hyperechoic strand was seen penetrating the anechoic vitreous from this retrolental tissue to the area of the optic nerve. Using color Doppler imaging, blood flow was evident in parts of the retina in both dogs. With power Doppler imaging there was blood flow in the lens and hyperechoic strand of the Basset hound on the first examination; whereas, on re-examination 5 months later, this was not found. Other abnormalities, such as retinal detachment, endophthalmitis, vitreous hemorrhage, microphthalmia, and posterior neoplasia could be excluded. 相似文献
103.
Jane M Morrell Anders Johannisson Anne-Marie Dalin Linda Hammar Thomas Sandebert Heriberto Rodriguez-Martinez 《Acta veterinaria Scandinavica》2008,50(1):2
Background
Artificial insemination is not as widely used in horses as in other domestic species, such as dairy cattle and pigs, partly because of the wide variation in sperm quality between stallion ejaculates and partly due to decreased fertility following the use of cooled transported spermatozoa. Furthermore, predictive tests for sperm fertilising ability are lacking. The objective of the present study was to assess sperm morphology and chromatin integrity in ejaculates obtained from 11 warmblood breeding stallions in Sweden, and to evaluate the relationship of these parameters to pregnancy rates to investigate the possibility of using these tests predictively.Methods
Aliquots from fortyone ejaculates, obtained as part of the normal semen collection schedule at the Swedish National Stud, were used for morphological analysis by light microscopy, whereas thirtyseven were used for chromatin analysis (SCSA) by flow cytometry. The outcome of inseminations using these ejaculates was made available later in the same year.Results
Ranges for the different parameters were as follows; normal morphology, 27–79.5%; DNA-fragmentation index (DFI), 4.8–19.0%; standard deviation of DNA fragmentation index (SD_DFI) 41.5–98.9, and mean of DNA fragmentation index (mean_DFI), 267.7–319.5. There was considerable variation among stallions, which was statistically significant for all these parameters except for mean_DFI (P < 0.001, P < 0.01, P < 0.001 and P < 0.2 respectively). There was a negative relationship between normal morphology and DFI (P < 0.05), between normal morphology and SD_DFI (P < 0.001), and between normal morphology and mean_DFI (P < 0.05). For specific defects, there was a direct relationship between the incidence of pear-shaped sperm heads and DFI (P < 0.05), and also nuclear pouches and DFI (P < 0.001), indicating that either morphological analysis or chromatin analysis was able to identify abnormalities in spermiogenesis that could compromise DNA-integrity. A positive relationship was found between normal morphology and pregnancy rate following insemination (r = 0.789; P < 0.01) and a negative relationship existed between DFI and pregnancy rate (r = -0.63; P < 0.05). Sperm motility, assessed subjectively, was not related to conception rate.Conclusion
Either or both of the parameters, sperm morphology and sperm chromatin integrity, seem to be useful in predicting the fertilising ability of stallion ejaculates, particularly in determining cases of sub-fertility. 相似文献104.
Vivi Flou Hjorth Jensen Anne-Marie M?lck Annette Heydenreich Karin Juul Jensen Line Olrik Bertelsen Lene Alifrangis Lene Andersen Henrik S?eborg Melissa Chapman Jens Lykkesfeldt Ingrid Brück B?gh 《Journal of toxicologic pathology》2016,29(1):17-30
New insulin analogues with a longer duration of action and a flatter pharmacodynamic profile are developed to improve convenience and safety for diabetic patients. During the nonclinical development of such analogues, safety studies must be conducted in nondiabetic rats, which consequently are rendered chronically hypoglycemic. A rat comparator model using human insulin would be valuable, as it would enable differentiation between effects related to either persistent insulin-induced hypoglycemia (IIH) or a new analogue per se. Such a model could alleviate the need for an in-study-comparator and thereby reduce the number of animals used during development. Thus, the aims of the present study were i) to develop a preclinical animal model of persistent hypoglycemia in rats using human insulin infusion for four weeks and ii) to investigate histopathological changes in sciatic nerves and quadriceps femoris muscle tissue, as little is known about the response to persistent hypoglycemia in these tissues. Histopathologic changes in insulin-infused animals included axonal degeneration and myofibre degeneration. To our knowledge, this is the first study to show that persistent IIH provokes peripheral nerve and skeletal myofiber degeneration within the same animals. This suggests that the model can serve as a nonclinical comparator model during development of long-acting insulin analogues. 相似文献
105.
The present study investigated daily sperm output and sperm morphology of fresh semen in eight Swedish Warmblood stallions aged 5–8 years. They were used for artificial insemination, and their fertility during the breeding season of semen collection exceeded 60% per cycle. One ejaculate of semen was collected daily for 10 consecutive days from each stallion. The gel-free volume was measured, and the sperm concentration was assessed with a Bürker chamber. The volume of gel-free fraction was multiplied by the sperm concentration to give the total number of spermatozoa (TSN). Sperm morphology was examined in ejaculates collected on days 2, 5 and 10. An aliquot from each ejaculate was fixed in 1 ml formol–saline immediately after collection and examined under a phase-contrast microscope (magnification 1000×) to assess morphological abnormalities. Furthermore smears were prepared and stained according to Williams (carbolfuchsin–eosin) for a more detailed examination of the sperm heads under a light microscope (magnification 1000×). Analysis of variance was applied to data. Total spermatozoa number decreased progressively during the first 8 days of collection, and daily sperm output (DSO) was calculated as mean TSN of collections on days 8–10, being 6.4 × 109 spermatozoa. The overall percentages of morphologically normal spermatozoa in ejaculates collected on days 2, 5 and 10 were above 70%, being significantly lower in ejaculate 2 (68.6%) compared with ejaculates 5 and 10 (72.9% respectively 75.3%). 相似文献
106.
107.
108.
研究旨在探讨响应面法优化漳州芽孢杆菌液态发酵桑叶粉的工艺及发酵之后产物的营养品质。以桑叶粉为原料、漳州芽孢杆菌为发酵菌种,以粗蛋白含量为响应值,通过响应面优化桑叶粉的液态发酵工艺。结果表明,漳州芽孢杆菌液态发酵桑叶粉的最优条件为料水比5.8%、装液量11.7%、发酵时间61 h、发酵温度34℃。在此条件下,漳州芽孢杆菌发酵桑叶粉所得产物中,分子量在1000 Da以下的肽百分比为97.4%。与原桑叶粉相比,漳州芽孢杆菌发酵桑叶粉所得产物的粗蛋白含量为17.456%,比原桑叶粉粗蛋白含量(14.029%)显著提高24.4%,小肽含量显著增加21.61%,必需氨基酸及总氨基酸含量显著升高,单宁含量显著降低34.71%,抗氧化活性显著增强。总体而言,漳州芽孢杆菌在优化的液态发酵条件下所制得的发酵桑叶粉,营养成分和品质、抗氧化活性显著提高,单宁含量降低,适口性提高。 相似文献
109.
徐大林 《吉林农业科技学院学报》2014,(3):19-22
对口援助背景下,充分认识创新少数民族大学生党建工作的重要意义,深入探索对口援助少数民族大学生党建工作存在的问题,创新对口援助少数民族大学生党员培养路径,为边疆少数民族地区输送政治可靠、留得住、用得上的高素质人才,推动边疆地区发展具有重要的现实意义。 相似文献
110.
Villiers E Baines S Law AM Mallows V 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2006,35(1):55-71
BACKGROUND: Flow cytometry may be used to determine immunophenotype or lineage of leukemic cells, but few antibodies are available that are specific for cells of monocytic and granulocytic lineage. OBJECTIVE: The purpose of this study was to evaluate the flow cytometric staining patterns of 3 commercial monoclonal antibodies for monocytes and granulocytes in clinically healthy dogs and in dogs with acute myeloid leukemia (AML). METHODS: Mouse antihuman macrophage antibody (MAC387), mouse anti-human myeloperoxidase (MPO), and a canine neutrophil-specific antibody (NSA) were evaluated using flow cytometry on blood from 6 clinically healthy control dogs, and on blood (n = 7) and/or bone marrow (n = 2) from 8 dogs with AML. A diagnosis of acute leukemia was confirmed by >30% blasts in bone marrow or >30% blasts in peripheral blood, together with bi- or pancytopenia, circulating CD34-positive blast cells, and clinical signs of disease. Leukemic samples also were evaluated using a wide panel of monoclonal antibodies. RESULTS: MAC387 stained neutrophils and monocytes from control dogs, although the staining profiles for the 2 cell types differed. MPO and NSA resulted in strong positive staining of neutrophils; MPO also stained monocytes weakly. Lymphocytes did not stain with any of the antibodies. One case was classified as AML of granulocytic lineage (AML-M1), 6 cases were classified as acute monocytic leukemia (AML-M5), and 1 case was classified as acute myelomonocytic leukemia (AML-M4). Neoplastic myeloblasts in the dog with granulocytic AML were positive for MPO, NSA, MAC387, and CD4. All monoblasts from the dogs with AML-M5 were positive for CD14, 5 of 6 were positive for MAC387, and 2 were positive for MPO. NSA staining was negative in the 2 dogs with AML-M5 in which it was evaluated. In the dog with AML-M4 variable percentages of blast cells were positive for CD14, MPO, MAC387, CD4, and NSA. CONCLUSIONS: Antigens identified by antibodies to MAC387, MPO, and NSA were expressed not just by normal mature neutrophils and monocytes, but also by neoplastic myeloblasts and monoblasts. These 3 antibodies may be useful as part of a wider panel for immunophenotyping AML in dogs. 相似文献