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71.
This study has aimed at observing in detail the degree of complexity in the formation of the ophthalmic rete in geese living at high altitudes and very cold climate conditions in Kars and its province of Turkey. The 15 adult geese were injected with red and blue coloured latex, dissection was performed, the rete was examined, and the vessels were counted macroscopically and by stereoscopic microscopy. The size and the afferent and efferent vessels of the rete were mostly in parallel with the literature. The numbers of the vessels in the rete of the male and female geese were between 8.3 +/- 1.1 and 9.3 +/- 1.1 in arteries, and 8.6 +/- 1.4 and 10.5 +/- 1.3 in veins respectively. The results suggest that the ophthalmic rete in the goose living at high altitudes and very cold conditions may tend to be less complex, which might be the result of the relatively less cooling needs of the brain at cold conditions.  相似文献   
72.
The efficacy of intramammary treatments containing procaine penicillin G alone (treatment A) or a combination of procaine penicillin G and neomycin (treatment B) was compared in treating clinical bovine mastitis caused by gram-positive bacteria susceptible in vitro to penicillin G. Both treatments were supplemented with a single intramuscular injection of procaine penicillin G on the first day of treatment. The study was carried out using a double blind design on commercial dairy farms in Southern Finland. A total of 56 quarters were treated with treatment A and 61 with treatment B. The cure rates for both treatments were equal, which suggests that the use of the penicillin G-aminoglycoside combination does not increase the efficacy of the treatment over that achieved by using penicillin G alone in bovine clinical mastitis caused by penicillin-susceptible, gram-positive bacteria.  相似文献   
73.
Quarter milk samples were taken from 48 clinically healthy, pregnant Finnish Ayrshire and Friesian dairy cows at the last milking before drying-off, and 2 and 6 days later to determine the lactoferrin and citrate concentrations in the udder secretion. The mean lactoferrin concentration in the milk increased from 5.29 mg ml(-1) on the last day of drying-off process to 8.09 and 11.26 mg ml(-1), 2 and 6 days later, respectively. Citrate concentration decreased from 1.85 mg ml(-1) to 1.54 and 1.09 mg ml(-1), respectively. Median molar ratio (citrate to native-Lf) decreased from 153 to 86 and further to 44. Lf and citrate concentrations in milk varied greatly among cows. Sampling time had a statistically significant effect on lactoferrin and citrate concentrations in milk while the breed and the parity of the cows had no effect on either of these variables.  相似文献   
74.
Fatty acids are increasingly used in the treatment of canine atopic dermatitis and their beneficial effects are documented in several prospective, controlled studies. Results from recent studies have indicated that atopic dogs have disordered fat metabolism, due to decreased desaturase activity. To further clarify these possible abnormalities, we examined serum fatty acid patterns in dogs with atopic dermatitis and normal controls. Atopic dermatitis was diagnosed according to the diagnostic criteria proposed by Willemse, after elimination of other possible causes of pruritic dermatitis. Both the relative and the absolute amounts of fatty acids in sera were determined by gas chromatography. Differences in the serum fatty acid pattern indicating a reduction in desaturase activity were not detected in atopic dogs when compared with controls.  相似文献   
75.
Diagnosis of Bovine spongiform encephalopathy (BSE) is confirmed by specified laboratory methods on brain material. On the other hand clinical signs of manifest BSE are quite obvious. The first part of this paper describes case histories, clinical signs, laboratory findings and the most common differential diagnoses. On the basis of the data of actual prevalence in Germany, the role of clinical examination in eradication of BSE is dealt in the second part. Clinical diagnosis is a very sensitive and specific method when there is a high prevalence. According to the data from December 2000 to November 2001 prevalence in Germany was beyond 1 BSE case per 100,000 cattle or 3 cases per 100,000 cows. This very low prevalence decreases rapidly sensitivity and specificity of the diagnosis made by clinical examination. Therefore the main focus of field-diagnostics has to be laid on specified laboratory diagnostic methods. On the other hand prevalence of BSE-positive cattle is distinctly higher in the group of animals slaughtered in cases of illness or emergency than in cattle slaughtered on the regulatory bases. Nevertheless every veterinary practitioner should be aware of the clinical picture of BSE, clinical examination-routine and differential diagnosis, because occurrence of BSE is still possible in any dairy herd. At the moment it is not possible to make any statement if eradication of BSE can be reached in future.  相似文献   
76.
This study focused on the morphological characteristics of the uropygial glands of the Japanese quail and silver polish, particularly the arterial nourishment. With this respect, coloured-latex injected animals were dissected and their glands and related arteries were observed. The gland in the Japanese quail was relatively longer than that in the silver polish. The first caudal segmental arteries in the Japanese quail were specialized as the uropygial gland artery while the fourth caudal segmental ones were continued as the uropygial gland artery in the silver polish. Branches from the second and third caudal segmental arteries and skin also contributed bilaterally to the vascularization of the gland in the Japanese quail. Observing the more complex arterial structure in the Japanese quail suggests more active uropygial gland in this species, when compared with the silver polish.  相似文献   
77.
内蒙古动物卫生监督信息化管理系统是在我国信息化、网络新技术不断完善基础上自主研发和创新中建立起来的,实现了多项功能全国领先,为内蒙古动物卫生监督工作的信息化管理做出了较大贡献.本文通过回顾动物卫生监督信息化管理系统的发展历程,描述了运用信息化管理系统提升当地动物卫生监督工作的效率和成绩,并建议进一步利用好当前的信息化、...  相似文献   
78.
1种子生产的现状1.1种子公司在种子生产基地建设上重经营,轻生产。主要表现基础设施薄弱,仓储、场地、仪器机械设备配套不足,限制种子生产基地的发展;投入财力不足,基地缺乏必要的科研、试验经费,技术力量缺乏,新品种试验、示范不能适应快速变化的市场需求。个...  相似文献   
79.
Several years ago, the presence of macrophages in the tumor microenvironment was thought to be an inflammatory response to kill the cancer cells. Now, this is clear that the inflammatory cells that exit blood vessels and migrate to the tumor tissue play an important role in cancer progression. Various cells present in the tumor microenvironment enhance cancer growth and invasiveness by secretion of tumor-enhancing products. That is why tumors should not be treated as only aggregates of cancer cells but as separate structures. Macrophages form a major component of the inflammatory infiltration in tumors, where they are termed tumor-associated macrophages (TAMs). To the best of our knowledge, up-to-date there were no studies on tumor associated macrophages and the role of the tumor microenvironment in tumor invasion/metastasis in dogs. This is the first study performed to asses if the number of TAMs and expression of MCSF-R (macrophages colony stimulating factor receptor) and CD14 (LPS co-receptor) are associated with the grade of tumor malignancy and its ability to metastasize. We have performed immunohistochemical analysis of 50 canine mammary adenocarcinomas of various grade of malignancy (1st, 2nd, 3rd) and tumors that gave local or distant metastases. The results indicate that in dogs, similarly to humans and mice, the number of tumor associated macrophages is related to the cancer ability to metastasize. Our results also indicate that the expression of MCSF-R and, what is particularly new finding, CD14 is associated with tumor malignancy and its ability to metastasize. Hence, these molecules play a role in tumor progression, metastasis and microenvironment interactions. These results show that in dogs we should treat the tumor as a whole organ rather than just try to eliminate the cancer cells.  相似文献   
80.
The effects of sevoflurane or isoflurane on arterial blood gas, arterial oxyhaemoglobin saturation and end-tidal CO2 tension were monitored during induction and maintenance of anaesthesia in 10 premedicated New Zealand White (NZW) rabbits.For induction, the anaesthetic agents were delivered via a face-mask. After induction was completed, an endotracheal tube was introduced for maintenance of anaesthesia for a period of 90 minutes. Changes in heart rate, respiratory rate, arterial blood gas, arterial oxyhaemoglobin saturation, blood pH and end-tidal CO2 tension were recorded. Although sevoflurane and isoflurane produce similar cardiopulmonary effects in premedicated rabbits, sevoflurane provides a smoother and faster induction because of its lower blood/gas partition coefficient. Thus sevoflurane is probably a more suitable agent than isoflurane for mask induction and maintenance. Its lower blood solubility also makes sevoflurane more satisfactory than isoflurane for maintenance of anaesthesia because it allows the anaesthetist to change the depth of anaesthesia more rapidly.  相似文献   
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