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81.
82.
The purpose of the study was a pathomorphological and immunohistochemical analysis of tumour cells and connective tissue in equine sarcoids. Investigations were performed using histopathological, ultrastructural, immunohistochemical (PCNA, p53, cytokeratin, vimentin) and histochemical (Ag-NORs) methods. The study was conducted on 50 sarcoids originating from 36 horses and classified as occult, verrucous, fibroblastic and a mixed type of sarcoid based on their clinical appearance. Most of the tumours were located on the girth (30%), neck (24%), head (12%), and legs (12%). The average age of the horses at the first clinical examination was 5.7 years. The sarcoids occurred on the skin of mares (61%), geldings (31%) and stallions (8%), the predominant was Wielkopolska breed (41%) and mixed breeds with Wielkopolska breed (41%). The predominant colour was bay (80%). The data showed that the presence of characteristic, microscopic features was variable but it was not consistent enough to allow differentiation of the clinical types based on histopathology. PCNA expression was not characteristic for the clinical type of sarcoid but it appeared to be a useful tool for the determination of the biological activity of the tumour and the probability of its recurrence. No relationship was found between AgNORs and cell proliferation. The study demonstrated the presence of p53 positive cells in the epidermal and fibroblastic portions. Numerous p53-positive cells were observed in the sarcoids and tended to recurrence. The staining for cytokeratin and vimentin makes the diagnosis of tumour easier. The immunohistochemical studies of PCNA, and p53 are of great significance to the prognosis.  相似文献   
83.
In both the horse and the man, nutritional ergogenic aids have been used to improve physical ability in conjunction with an appropriate training regimen. Although training increases physical condition, the ease of taking a nutritional additive to improve training results explains the demand for supplementation, which may increase mechanical energy of work, delay onset of fatigue, or improve neuromuscular coordination. The purpose of this study was to determine the effects of oral supplementation of β-hydroxy-β-methylbutyrate (HMB) and γ-oryzanol (GO) on indices of exercise-induced muscle damage in Thoroughbred race horses. In this 32-week study, the horses were assigned to either a placebo, GO (3.0 g/d), HMB (15 g/d), or GO and HMB treatment groups. The supplements were administered for the first 16 weeks of the study during the training period before the racing season began. Blood samples were taken at baseline, and then during training, before exercise, immediately after exercise, and 30 minutes after exercise. Heart rate and speed were monitored in each exercise session. Hematocrit, glucose, lactate (LA), creatine phosphokinase, and aspartate aminotransferase were measured before and after each exercise session. Analysis of variance showed a significantly greater increase in postexercise creatine kinase activity in placebo-supplemented group than in the other treatment groups, both in the training period and during the racing seasons (P < .05). Blood LA was higher immediately after exercise in the placebo group compared with the supplemented groups. In conclusion, supplementation with HMB and GO resulted in decreased creatine kinase and LA after exercise. These findings support the hypothesis that HMB and GO supplementation helps to prevent exercise-induced muscle damage.  相似文献   
84.
Antioxidative status consists of two mechanisms: nonenzymatic and enzymatic mechanisms. Nonenzymatic mechanisms are composed of antioxidants, scavengers of free radicals, transition metal ions, sequester transition metal ions, albumins, ceruloplasmin, and metallothioneins. On the other hand, enzymatic mechanisms are composed of superoxide dismutase (SOD), peroxidase, catalase and reductase. In cattle, characteristics of these mechanisms depend on the nutritional status of anti-oxidant minerals, especially copper, zinc, iron, selenium, silicon, and manganese. The nutritional status of the cattle in different regions of the world and in Poland is often characterised by the lack of these minerals; therefore, there is a great potential for changes in the activity of defence mechanisms against free radicals.  相似文献   
85.
E. coli strains isolated from pigs with postweaning diarrhea or edema disease were tested by phenotypic and genotypic methods for the presence of virulence antigens and genes, respectively. The slide agglutination and ELISA analyses were used for determination of F4, F5, F6, F17, and F41 fimbriae whereas the prevalence of fimbrial fedA and toxin eltI, estI, estII, stx1, stx2 and stx2e genes were recorded by the means of PCR. Only F4 antigen (ac variant) was found in strains of the serogroup O149:K91 isolated from pigs with diarrhea. PCR analyses showed that the fedA gene encoding F18 fimbriae was present in 61.9% of strains isolated from pigs with diarrhea and in 84.2% of strains isolated from pigs with edema disease. The eltI genes encoding heat-labile toxin I (LTI) were present only in 9 out of 21 strains recovered from pigs with diarrhea. Shiga toxin 2 variant (stx2e) genes were found in six isolates from edema disease and also in one strain from diarrhea. The PCR test used in the study was a sensitive and valuable method for determination of virulence factors of E. coli strains.  相似文献   
86.
The content of iron, zinc, copper, manganese, lead, and cadmium was determined in the kidney, liver, and abdominal muscle of the brown hare (Lepus europaeus), a species known for its bioindicative potential in environmental quality assessment. The animals assayed were divided into immature (in their first year of life; n=25) and adult (n=39). The hares were acquired in an area situated far away from major cities and direct impacts of industrial and transport pollution. The zinc content found in the assayed hare's muscles (25.9 microg/g w.w.) and that of manganese in the kidneys, liver, and muscles (2, 2.51 i 0.85 microg/g w.w., respectively) tended to be higher than those reported from the brown hare elsewhere in Europe. The content of cadmium (particularly in the kidneys) and lead proved substantial and close to those typical of the hare inhabiting industry-affected areas. Analysis of the data pooled for all the individuals showed Zn and Cd contents to increase with age in the kidneys, the liver Cd content increasing with age as well; on the other hand, the age-Cu content was negative. In addition, a number of significant correlations between the metals themselves were revealed, particularly with respect to Zn-Cd correlation in kidneys (r(s)=0.47), Fe-Cd, Zn-Cu, Mn-Zn, Mn-Cu, and Mn-Pb in the liver (r(s) of 0.42, 0.86, 0.72, 0.79, and 0.42, respectively), and Zn-Cu in the muscle (r(s)=0.56). The kidney cadmium content was higher by 81% in the adult than in the immature hare, the adult hare muscle copper content being lower by 15.5%.  相似文献   
87.
Local immunity of the respiratory mucosal system in chickens and turkeys   总被引:1,自引:0,他引:1  
This review article presents fundamental mechanisms of the local mucosal immunity in selected regions of the respiratory tract in healthy birds and in some pathological conditions. The respiratory system, whose mucosa come into direct contact with microorganisms contaminating inhaled air, has some associated structures, such as Harderian gland (HG), conjunctive-associated lymphoid tissue (CALT) and paranasal glands (PG), whose participation in local mechanisms of the mucosal immunity has been corroborated by numerous scientific studies. The nasal mucosa, with structured clusters of lymphoid tissue (NALT - nasal-associated lymphoid tissue) is the first to come into contact with microorganisms which contaminate inhaled air. Lymphoid nodules, made up of B cells with frequently developed germinal centres (GC), surrounded by a coat of CD4+ cells, are the major NALT structures in chickens, whereas CD8+ cells are situated in the epithelium and in the lamina propria of the nasal cavity mucosa. Studies into respiratory system infections (e.g. Mycoplasma gallisepticum) have shown the reactivity of the tracheal mucosa to infection, despite a lack of essential lymphoid tissue. Bronchus-associated lymphoid tissue (BALT) takes part in bronchial immune processes and its structure, topography and ability to perform defensive function in birds is largely age-dependent. Mature BALT is covered by a delicate layer of epithelial cells, called follicle-associated epithelium (FAE). Germinal centres (GC), surrounded by CD4+ cells are developed in most mature BALT nodules, while CD8+ lymphocytes are dispersed among lymphoid nodules and in the epithelium, and they are rarely present in GC. Macrophages make up the first line of defence mechanisms through which the host rapidly responds to microorganisms and their products in the respiratory mucosal system. Another very important element are polymorphonuclear cells, with heterophils being the most important of them. Phagocytic cells obtained from lung lavages in birds are referred to as FARM (free avian respiratory macrophages). Their number in chickens and turkeys is estimated to be 20 times lower than that in mice and rats, which indicates a deficit in the first-line of defence in the birds' respiratory system. There are numerous B cells and antibody secreting cells (ASC) present throughout the respiratory system in birds. Their role comes down to perform antigen-specific protection by producing antibodies (IgM, IgY or IgA class) as a result of contact with pathogenic factors.  相似文献   
88.
Echinacea purpurea (EP) and Echinacea angustifolia (EA) are ones of the most important world's herbs with immunotropic activity. They were traditional medicinal plants used by North American Indians for the treatment of various illnesses. Now they are cultivated in many countries and are used mainly to treat respiratory tract infections. Rhodiola rosea (RR) and Rhodiola quadrifida (RQ) are medicinal plants originated from Asia and used traditionally as adaptogens, antidepressants, and anti-inflammatory remedies. We previously reported, that extracts of underground parts of RR and RQ exhibited immunotropic activity. We have demonstrated in pigs that in vitro RR or RQ supplementation of blood lymphocyte cultures stimulated T cell proliferative response to Con A in lower, and inhibited it in higher Rhodiola extract concentrations. The aim of this work was to evaluate the in vivo effect of these herbal remedies on the in vitro proliferative response of mouse splenic lymphocytes to another T-cell mitogen- Phaseolus vulgaris haemagglutinin (PHA). We have found significant stimulation of proliferative response, in comparison to the controls, in mice fed lower doses of tested remedies, and inhibition, no effect or lower stimulation, in mice fed higher doses of these drugs.  相似文献   
89.
The aim of the present paper was to determine an influence of the presence and a level of intestine parasites infection on the quality of pork carcass expressed by the content of meat in carcass (meatiness) in pigs. The experimental part of the study was conducted on pigs farm produced in a closed cycle. The population in the study included 120 fattening pigs maintained in two keeping systems: group I--60 individuals kept on slatted floor, and group II--60 individuals kept on deep litter. All the experimental animals were treated in the same manner. The analysed fatteners were slaughtered in Meat Processing Plant when their body mass reached 110 kg, and the post-slaughter assessment was conducted according to the EUROP classification of pigs carcass using the Ultra-Fom 300 device. The study concerning the internal parasites were conducted basing on coproscopic quantitative McMaster method. As a results, the eggs of three nematode taxa were isolated and identified: Oesophagostomum spp., Ascaris suum and Strongyloides ransomi. Overall prevalence of infection of fatteners kept on litter was lower (25%±11.2) as compared to those kept on slatted floor (38.3%±12.6), however the differences were not statistically significant (χ(2)=2.465; df=1; P=0.116). The mean value of meatiness for pigs free from parasites was 53.68, while in the case of infected pigs the meatiness was statistically lower and was 52.12 (t=2.35; P=0.02). The analysed pigs were classified into three categories and conducted analysis of an influence of parasites on meatiness demonstrate the relationship that is statistically significant. The analysis of correlation between meatiness and an average number of helminth eggs also demonstrated the negative, statistically significant, relationship (F=5.52; P=0.020), i.e. in fatteners with higher EPG value the meatiness was lower.  相似文献   
90.
Real-time PCR directed to intergenic spacer (IGS) noncoding region between 16S and 23S rRNA genes was used for species specific detection of Mycoplasma felis in conjunctival scrapings. Samples were collected from 57 cats suffering from chronic conjunctivitis in 2008-2010 (Wroc?aw, Poland). Samples from 36 cats (63.2%) were shown to be positive for Mycoplasma felis. Our research gives a first insight in the occurrence of Mycoplasma felis among domestic cats in Poland suggesting that this pathogen may constitute an underestimated cause of chronic conjunctivitis.  相似文献   
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