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Granulowaną lecytynę podawano doustnie zdrowym ochotnikom przez 30 dni. Badania wykazały, że otrzymany z soi preparat lecytyny posiadał właściwości modyfikowania układu immunologicznego. Aktywacji ulegał zarówno swoisty, jak i nieswoisty układ obronny.
Six thoroughbred horses formed a study group which was immunized twice with a vaccine (Equigrip, Rhone-Merieux), the control group was six unvaccinated horses. Blood was collected for hematological examinations, cellular immune responses, specific humoral immunity (HI) at days 0, 17, 34, 83, 117 and 123 of the experiment. On day 117 of the experiment, 3 horses of the experimental group and 3 horses of the control group were infected intranasally with a mixture of 2 subtypes (A-l and A-2) of the influenza virus. It is worth noting that 17 days after the first vaccination the lymphocyte stimulation index increased in all horses in the experimental group, while in four of the six unvaccinated horses (control) the index decreased. During this time a statistically significant increase of the specific antibodies titres was not found in vaccinated horses. Six days after the infection, the fairly high level of specific humoral immunity was accompanied by a strong stimulation of cellular immunity, which was expressed as a statistically significant increase in the lymphocyte stimulation index (as determined by the specific blastic transformation test) and was higher in vaccinated horses. Reisolation of the virus, which was attempted five days after the challenge from the nasal cavities of vaccinated horses was unsuccessful, while influenza virus subtype 2 was isolated from each of the vaccinated horses.
The goal of the studies was evaluation of the influence of some parameters of cellular immunity on age and anatomo-pathological lesions in the bison. The results of the studies show an influence of the state of health of the bison as measured in a system of assessing points for various gross pathological lesions, on an importent cellular immunity parameter (reactions level of lymphocytes to mitogen (PHA). The better the ability to mobilize lymphocytes the better the health condition of the bison was found to be (lower amount of anatomopathological points). At the same time a higher mobility of lymphocytes was found in older animals. Results of hematological tests. Which showed higher total lymphocyte and leucocyte numbers (per 1 mm³ of blood) also suggest, a better effectiveness of the immunologic system in older animals.
In terms of its anatomy and functions, the reproductive system of birds is significantly different from the one found in mammals. It consists of only the left ovary and the left oviduct, which is constantly exposed to ascending infections because of its connection with the cloaca. Hence, the proper functioning of humoral and cell-mediated local immune mechanisms in this system is very important for maintaining its physiological functions. The expression of Toll-like receptors and the presence of T and B lymphocytes have been demonstrated in both the ovary and the oviduct of chickens. CD4⁺ T cell subpopulation is distributed mainly in the lamina propria of the oviduct, whereas in the submucous membrane and muscular layer these cells are found less frequently. CD8⁺ T lymphocytes are equally distributed in all abovementioned layers of the oviduct wall. IgY⁺ B cells are distributed among the epithelial cells, and they are closely connected with the glandular tissue of the oviduct, mainly in the infundibulum, magnum, and uterus regions. IgA⁺ and IgM⁺ B cells are present in the entire oviduct, but mainly in the glandular tissue of the magnum. IgY⁺ B cells have not been detected in the ovary, unlike IgM⁺ B cells, which have been demonstrated in the ovary stroma. In addition to T and B cells, antigen-presenting cells are present in the follicle wall and in the oviduct. During the early stages of reproductive maturation, a decrease in the number of immunocompetent cells is observed in the reproductive system, and the local immnosuppression increases the susceptibility of birds to Salmonella Enteritidis infections. The number of T and B lymphocytes in the mucous membrane of the oviduct decreases with age, which facilitates infections of the reproductive system. Additionally, the local immune mechanisms of the reproductive system in birds involve the transfer of protective IgY, IgA and IgM maternal antibodies to hatching eggs. The local immune mechanisms of the reproductive tract are responsible for preventing infections that disturb the physiological functions of the reproductive system and for protecting eggs from contamination.
The aim of this study was to determine the influence of oxytetracycline given per os at a dose of 0.5 g/L in drinking water for 5 days on selected parameters of the cell-mediated immunity of 5-week-old turkeys. The research was carried out on forty turkeys divided into two groups (20 birds per group). The percentage of CD3+CD4+ and CD3+CD8+ T lymphocytes as well as IgM+ B lymphocytes were determined by flow cytometry in the blood and spleens of turkeys in the control and in the experimental group after 5 days of oxytetracycline administration and 6 days later. The results of this study show that oxytetracycline given per os (0.5 g/L) as outlined above, has no effect on the percentage of the CD3+CD4+ T lymphocyte subpopulation in the blood of turkeys. On the other hand, we were able to determine that it caused a statistically significant decrease in the percentage of CD3+CD8+ T and IgM+ B lymphocyte subpopulations in blood. The results show that six days after the administration of the antibiotic, there was a statistically significant decrease in the percentage of the CD3+CD8+ T lymphocyte subpopulation among the mononuclear cells of the spleen. A significant decrease in the CD3+CD4+ T lymphocyte subpopulation percentage and an increase in the IgM+ B lymphocyte subpopulation percentage in the spleen were recorded both after 5 days of oxytetracycline administration and 6 days later in the experimental groups of turkeys. It can be claimed that oxytetracycline given to turkeys at a dose of 0.5 g/L for five days in drinking water causes the immunosuppression of the cell-mediated mechanisms of their immune system, which can lead to infections by opportunistic pathogens, as well as weakened post-vaccination immunity.
The aim of the study was to estimate the influence of β-1,3/1,6-D-glucan applied in feed on non-specific cellular immunity in lambs. The study examined twenty six 21-28 day old lambs in two groups: I - control and II - experimental (7 rams and 6 ewes in each group). The animals were kept under identical zoohygienic and nutritional conditions. Lambs from group I were fed a basal control diet and lambs from group II were fed a diet containing β-1,3/1,6-D-glucan, at doses of 80 mg/kg/day. Blood was taken from the control and experimental groups before the lambs were fed a diet containing β-1,3/1,6-D-glucan, and 15, 30 and 60 days after administration of the diet. The respiratory burst activity (RBA) and potential killing activity (PKA) of blood phagocytes and proliferative response of blood lymphocytes (MTT) stimulated by mitogens concanavalin A (ConA) and lipopolisaccharide (LPS) were examined. The results indicated that when β-1,3/1,6-D-glucan was applied to food it statistically significantly increased the blood phagocyte and lymphocyte activity in the lambs until the end of experiment, compared to the control group.
The aim of the study was to determine the immunological state of bitches suffering from pyometra. The study was performed on 87 bitches with open pyometra, 13 bitches with closed pyometra and 17 healthy control bitches. All bitches with pyometra were treated by ovario-hysterectomy. Prior to surgery, blood samples were collected from them to determine: w.b.c., r.b.c., Hb, Ht, differential w.b.c. A NBT reduction test and phagocytic index was also performed on the blood. In addition, the lysozyme activity, total protein level and globulin fraction were evaluated in the serum. C-reactive protein (CRP) was determined in 40 of the bitches. Uterus aspirates were collected from 68 bitches with open pyometra and 13 with closed pyometra for bacteriological examination. The study demonstrated that all immunological parameters in bitches with pyometra were lower compared to those of the control group. Only the CRP level was very high. In bitches with open pyometra the following aerobes were isolated: E. coli (78%), streptococci (13%), staphylococci (6%) and Pseudomonas aeruginosa (3%). No aerobes were isolated in bitches with closed pyometra.
The examinations were done on 7 healthy Polish ponies from 1.5 to 14 years of age. The experimental animals were intravenously injected Escherichia coli LPS at a dose of 0.1 µg/kg b.w. Clinical observations and blood collection for laboratory examinations from the external neck vein were done just before endotoxin injection and then for 8 hours at one hour intervals and after 24, 48, 72 and 96 hr. from endotoxin application. All horses were examined routinely clinically (rectal temperature, pulse, respiration rate) and hematologically (total number of leukocytes, differential leukocyte count). Phagocytic activity of neutrophilic granulocytes was evaluated on the basis of the percentage of phagocytic cells (KF) and the phagocytic index (IF) using a standard Staphylococcus aureus strain. Moreover, the nitrotetrazolium blue reduction test (NBT) was done by a microquantity method. Clinical observations and hematological examinations in the experimental animals were typical for endotoxemia of horses. It was also found that LPS of E. coli at the administered dose stimulates unspecific immunity because it increases the value of KF, IF and NBT during the whole period of experimentation.
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