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1.
抗原物质引起滤泡的形成:一次投入与多次投入的比较   总被引:2,自引:0,他引:2  
实验以不同方式投入抗原物质,即一次投入与分次投入,并观察了新产生滤泡数,维持的滤泡数,实验用小鼠24 只, 于足底注入铝和钥孔 血蓝素附合物(AKLH), 分一次注入与三次注入组; 三次注入组又分间隔5 日及间隔二周注入。注入后第3 周与第12 周分别取出腘淋巴结,应用免疫组化法,第三周末观察可见一次投入产生的滤泡多, 而第十二周发现分次投入维持的滤泡数多。可见反应性滤泡的形成, 不仅与刺激物的性状和投入量有关, 而且与投入的方法有关  相似文献   

2.
Three groups of Wistar-rats were exposed to permanent noise (80 db) during different periods in their postnatal life: the first group was exposed starting from birth for a period of four weeks, the second one from birth up to nine weeks of age and the third group from the fifth up to the ninth week postnatal. A fourth group (control animals) was reared under normal laboratory conditions. After the experiments the brains were exposed to a modified GOLGI-method. In lamina-V-pyramids of the gyrus cinguli lightmicroscopical results: length, number and distribution of spines on the main apical dendrites and on the apical dendritic branches where evaluated. Main results: 1. Permanent noise during the early postnatal development phase of the brain of rats (from birth up to the fourth week of age) causes a statistically significant increase of apical spines. The spines-values are 20% above those of the control animals. 2. Permanent noise from birth up to the ninth week of age or applied only during the later postnatal period (from the fifth week up to the ninth week of age) does not significantly alterate the spines-value. 3. The results are estimated as a consequence of extreme environmental factors causing effects, comparable with an universal stress reaction. Conclusions were discussed in comparison to the results of other authors.  相似文献   

3.
BALB/c mice and BN rats manifesting persistent IgE and IgG responses were examined up to 1 year after immunization. A significant proportion of the ongoing antibody response in these animals survived lethal X-irradiation employing dosages sufficient to deplete B memory cells. The persistent IgE responses in both species were refractory to exogenous isotype-specific suppressor cells taken from tolerant syngeneic animals, which were shown to abrogate primary IgE responses in parallel tests. Employing a novel ELISA-based assay for plaque forming cells, long-lived radioresistant IgE- and IgG-secreting cells were identified in differing ratios in lymph nodes, spleen, and bone marrow of both species. These long-lived cells were shown to arise following maximum antigenic challenge with antigen plus adjuvant, and after repeated low-grade stimulation by antigen alone, including passive inhalation of dilute antigen aerosols.  相似文献   

4.
Experimental studies in animals and recent preliminary clinical evidence raised the possibility that hypertransfusion might be capable of producing a beneficial effect on granulopoiesis recovery following irradiation or chemotherapy. This prompted us to design a study to determine the effect of hypertransfusion on the blood and marrow CFU-c of leukemic children during remission induction. Nineteen children with acute lymphoblastic leukemia have been randomized in pairs to normotransfused (Hb: 12-14 g/dl) and hypertransfused (Hb: 16-18 g/dl) groups. Anti-leukemic chemotherapy (vincristine and adriamycin weekly during 4 weeks and prednisone daily) was identical in all children. As expected, suppression of erythropoiesis was observed in the hypertransfused group. During the first three courses of chemotherapy, the number of marrow CFU-c remained very low in both groups. One week after the third course of chemotherapy the number of bone marrow CFU-c began to increase in both groups. One week after course four the CFU-c value was significantly larger in the hypertransfused group. We also observed that circulating CFU-c were almost absent before induction chemotherapy, whereas their number increased after course three and was higher in the hypertransfused group and remained higher after course four. These results show the kinetics of bone marrow recovery after chemotherapy and suggest that hypertransfusion increases the rate of recovery of granulopoiesis.  相似文献   

5.
The antimutagenic potential of glutathione (GSH) on mitomycin C (MMC)-induced micronuclei was evaluated in Swiss albino mice using the in vivo bone marrow micronucleus test. Six groups of animals were maintained simultaneously. The first group received distilled water only, the second group of animals received 2 mg/kg MMC and the third group was administered 4 doses of GSH, i.e., 20, 40, 80 and 160 mg/kg. The fourth group of animals received GSH and MMC simultaneously. The fifth and sixth groups received a cumulative dose of GSH followed by MMC after 24 h. The fifth group of animals were killed 6 h after the administration of MMC, while the sixth group were killed 24 h after the administration of MMC. The results clearly show a statistically significant increase in micronuclei in MMC-treated animals and also in animals that received GSH followed by MMC. However, there was a decrease in micronuclei in animals that received GSH and MMC simultaneously. The results clearly indicate that GSH exhibits an antimutagenic property in the presence of MMC. It is also observed the treatment with GSH prior to MMC does have some protective effect.  相似文献   

6.
The zinc sulphate turbidity test was used to establish the total immunoglobulin levels of calves from birth to 4 months of age. Colostral immunity fell rapidly and the lowest levels were found in the third and fourth week of life. During the fifth week there was a significant increase. 25% of animals were hypogammaglobulinaemic in the first week of life. This ratio increased to 50% in the third week of life. At the age of two months the lowest immunoglobulin levels almost vanished. These findings are discussed as basic information for the appropriate management of calf agglomerations. Animals should be agglomerated only after the first months of life. When this is not possible, the pens for large agglomerations should have individual housing for the newly admitted calves. The importance of appropriate epizootological measures to reduce infections are pointed out.  相似文献   

7.
The influence of human interleukin-1 beta in different concentration on processes of postirradiation recovery of haemopoietic precursors (GM-CFC) and morphology of recognized elements of bone marrow were studied in long-term bone marrow cultures during 28 days after gamma-irradiation with a dose of 2 Gy. It was studied also the action of interleukin-1 beta on proliferation, the contents of GM-CFC and the induction of GM-CSF in non-irradiated cultures. It was shown that the injection of interleukin-1 beta increased proliferation and the content of GM-CFC and also raised an induction of GM-CSF in the non-irradiation cultures. The maximum increase of a level of GM-CSF, amount of GM-CFC and proliferation of GM-CFC was marked in 20 hours after the injection of cytokine. Under irradiation of long-term bone marrow cultures the maximum stimulation effect to recovery of GM-CFC, total number of myelocaryocytes and the content of immature and mature granulocytes were observed after the injection of interleukin-1 beta in concentration of 0.005 microgram/ml 20 hours prior to radiation exposure. The data of this report suggest that one of the mechanisms of radioprotective action of interleukin-1 beta apparently is connected with stimulation action on hematopoietic microenvironment cellular elements that causes the release of GM-CSF or/and other cytokines, and stimulation recovery of haemopoietic precursors.  相似文献   

8.
The effect of prolonged treatment with weak microwaves on the production of tumor necrosis factor and interleukin-3 in peritoneal macrophages and T cells of male NMRI mice twice immunized by affinity-purified carboanhydrase was studied. Against the back ground of a high titer of antibody production, a significant increase in the production of tumor necrosis factor in peritoneal macrophages and splenic T lymphocytes of immunized mice was revealed, and a much stronger effect was observed for irradiated immunized animals. A tendency to increased secretion of interleukin-3 for unirradiated and irradiated immunized animals was found; in the latter group of animals, the effect being more pronounced. The stimulation of production of the cytokins, especially tumor necrosis factor, by combination of antigenic stimulation and microwaves can be used in adjuvant therapy of various immune diseases.  相似文献   

9.
The effect of intraperitoneal administration of cGMP (0.5 mg per animal) on carbohydrate metabolism of wound area muscle tissue was studied in experiments on rats with linear skin wounds. The content of glycogen, gluconeogenesis, activity of glycogen phosphorylase, lactate dehydrogenase and malate dehydrogenase were studied. Cyclic GMP induced a substantial activation of glycogen metabolism (elevation of gluconeogenesis, increase in the activity of glycogen phosphorylase) even the third day after the operation. The animals not given cGMP demonstrated such an activation only the fifth day following the operation. Under the effect of cGMP the activity of lactate dehydrogenase rose the third day after the operation. Thus cGMP administration to the animals with wounds leads to an earlier mobilization of energy resources thereby promoting the acceleration of wound healing.  相似文献   

10.
Granulocyte and macrophage progenitor cells forming colonies in vitro (GM-CFC) from bone marrow, spleen, and peripheral blood of BALB/c mice infected with Plasmodium berghei were cultured at various times postinfection in a viscous, 0.8% methylcellulose system. The numbers of GM-CFCs from bone marrow increased gradually during the first week of infection, reaching a maximum around the tenth day of the disease. Subsequently, a rise of GM-CFCs in cultures of nucleated cells from the peripheral blood was observed and, with some delay, in spleen cell cultures also, with a maximum around the end of the second week. After the tenth day of malaria infection a fall of colony frequency in bone marrow-derived cells took place, leading to subnormal values of GM-CFCs during the third week of infection. Subsequently, a decrease in the spleen cell cultures followed, but colony numbers did not fall to normal values. The general increase in GM-CFCs in the different organs was preceded by a rise in serum levels of colony-stimulating activity (CSA), attaining a maximum 1 week after P. berghei inoculation. During the following period the CSA levels fell and reached normal values around the seventeenth day of the disease. Chemotherapy with chloroquine started on the fifteenth day of infection, when GM-CFCs in the bone marrow have dropped to normal values, stopped their further decrease. In the spleen a gradual normalization took more than 2 weeks. A challenge infection evoked an elevation of GM-CFC numbers in the bone marrow and in the spleen during the first 10 days in only about 50% of immune mice. The reaction was immediate in some animals, but generally lower and of shorter duration than during primary infection. The results have indicated that a lethal P. berghei infection in mice caused a transient increase in production of CSA followed by a general recruitment of GM-CFCs in all hemopoietic organs.  相似文献   

11.
An attempt was made to determine if there is any common mechanism in the enhanced antibody response caused either by injection of adjuvant, such as bacterial endotoxin (LPS) and complexed polynucleotides, or by secondary antigenic stimulation. LPS inoculated in mice 4 days before injection of sheep red blood cells (SRBC) and polyA:U invalidated the adjuvant effect of polyA:U injected together with SRBC, and the hemolysin plaque-forming cell (PFC) response of such mice was similar to that of the mice which received SRBC alone. When mice primed with SRBC 24 days in advance were injected with LPS and 4 days later re-stimulated with SRBC, their PFC response to the secondary stimulation was suppressed to less than one tenth of the normal secondary PFC response. The suppressive effect of LPS on the secondary antibody response was abolished if the serum collected from mice injected with LPS was given to the primed and LPS-injected mice at the time of the secondary antigenic stimulation. From these results we discussed the possibility that some common mediator might play a role in the enhanced antibody response elicited by either adjuvant injection or secondary injection of antigen.  相似文献   

12.
Studies have been made of marrow restoration after localized depletion of the rabbit femur by dextran perfusion. Restoration was shown to involve an initial period of reorganization which blends with a more prolonged period of hemic cell repopulation. Cellularity returned to normal levels by 35 days, the recovery of myeloid cells being somewhat more rapid than that of the erythroid elements. In either case, the evolution of immature hemic cells was soon followed by the appearance of more mature forms even at the earliest stages of marrow repopulation. 3H-TdR uptake per cell increased rapidly to a level approximately twice normal after the first week. The augmented incorporation of thymidine, revealed by scintillation spectrometry and confirmed upon autoradiography, was shown to be due to an increase in DNA synthesis rate as well as in the fraction of participating cells. It is suggested that the enhanced cell production is brought about by a decrease in the proliferative cell cycle and an increase in the growth fraction. The origin of the repopulating cells remains a moot point. Cell migration from the epiphyseal marrow is apparently not involved. Irrespective of the source of stem-type cells, the stimulus for regeneration appears to be locally determined.  相似文献   

13.
Yearling cross-bred heifers were injected with 0.4 or 4 mg total protein in non-ulcerative Freund's adjuvant (Groups A and C, respectively; N = 5 per group), or adjuvant with C. parvum (Groups B and D, respectively; N = 5 per group). Control heifers were not treated (N = 9). No antibodies were detected in heifers in Groups A and C and so these were excluded from the analysis. There was no effect of the treatment on Group B or D heifers after the priming or first booster injection. After a second booster injection one Group D heifer gave a triple ovulation, and two Group D heifers and one Group B heifer gave double ovulations, but for one oestrous cycle only. Group B heifers also showed a significant rise in FSH concentrations after the second booster injection. Group D heifers were given a third booster injection; there was an increase in the mean number of large follicles per heifer, and a decrease in oestrous cycle length, but no increase in ovulation rate. These results indicate that a transient increase in ovulation rate can be induced by actively immunizing cattle against partly purified follicular fluid from sheep.  相似文献   

14.
A multiple dose IL-1 therapy was evaluated for its capability to stimulate hematopoiesis in normal primates and to restore hematopoiesis after autologous bone marrow transplantation. The administration of IL-1 to normal animals over a dose range of 0.5 to 10 ug/kg/d led to a 7-12 fold increase in peripheral blood neutrophil and monocyte counts after 24 hours. This increase in the mature peripheral blood myeloid cells was followed by changes in the myeloid composition of the bone marrow, where the percentage of myeloid elements increased along with a transient increase in myeloid progenitor cell activity. IL-1 treatment also led to an initial decrease in platelet counts of 10-30% during the first 3 days of treatment. However, a striking finding was a significant and long lasting stimulation of increased platelet production with platelet counts increasing to 77% of baseline 3 days after cessation of treatment and remaining elevated for the next 10 days. The therapeutic potential of the IL-1 regimen to restore hematopoiesis was further evaluated in an established autologous bone marrow transplantation model. In monkeys receiving IL-1 doses, 1.0 and 5.0 ug/kg/d, neutrophil counts recovered to >0.5 x 10e9/1 on day 16, one day earlier than control, but the recovery to baseline neutrophil counts occurred 5 days sooner than control. IL-1 therapy had its greatest effect on the restoration of platelet counts after transplantation, reaching >100 x 10e9/l by day 21, two weeks earlier than control. This work demonstrates that IL-1 therapy stimulates myelopoiesis but its most promising clinical application is the stimulation of platelet production.Views presented in this paper are those of the authors: no endorsement by the Department of the Navy or the Defense Nuclear Agency has been given or should be inferred. This work was supported by the Naval Medical Research and Development Command, Research Task No. 63706N MM095.003.1007 and the Defense Nuclear Agency Work Unit No. 132082.  相似文献   

15.
1. Ontogenetic shifts in predator behaviour can affect the assessment of food‐web structure and the development of predator–prey models. Therefore, it is important to establish if the functional response and interference interactions differ between life‐stages. These hypotheses were tested by (i) comparing the functional response of second, third, fourth and fifth larval instars of Rhyacophila dorsalis, using three stream tanks with one Rhyacophila larva per tank and one of 10 prey densities between 20 and 200 larvae of Chironomus sp.; (ii) using other experiments to assess interference within instars (two to five larvae of the same instar per tank), and between pairs of different instars (one, two or three larvae per instar; total predator densities of two, four or six larvae per tank). 2. The first hypothesis was supported. The number of prey eaten by each instar increased with prey density, the relationship being described by a type II model. The curvilinear response was stronger for fourth and fifth instars than for second and third instars. Mean handling time did not change significantly with prey density, and increased with decreasing instar number from 169 s for fifth instars to 200 s for second instars. Attack rate decreased progressively with decreasing instar number. Handling time varied considerably for each predator–prey encounter, but was normally distributed for each predator instar. Variations in attack rate and handling time were related to differences in activity between instars, fourth and fifth instars being more active and aggressive than second and third instars, and having a higher food intake. 3. The second hypothesis was partially supported. In the interference experiments between larvae of the same instar or different instars, mean handling time did not change significantly with increasing predator density, and attack rate did not change for second and third instars but decreased curvilinearly for fourth and fifth instars. Interference between some instars could not be studied because insufficient second instars were available at the same time as fourth and fifth instars, and most third instars were eaten by fourth and fifth instars in the experiments. Prey capture always decreased with decreasing attack rate. Therefore, interference reduced prey consumption in fourth and fifth instars, but not in second and third instars. The varying feeding responses of different instars should be taken into account when assessing their role in predator–prey relationships in the field.  相似文献   

16.
The use of Gallamycin to control nasal deterioration and permit increased growth rates in bacon type pigs was studied. Litters were randomly divided according to sex into treatment and control groups. Animals were treated by injection with 2.5 mgm of Gallamycin per pound liveweight at weekly intervals commencing during the first through the fifth week of age. Treatments ceased during the eighth week of age. Gallamycin treatment did not reduce significantly the percentage of nasal turbinate degeneration nor increase the rate of gain per day of treatment compared with control animals within litters. Possible explanations of results obtained are hypothesized.  相似文献   

17.
Liver glycogen levels were measured in rats with hippocampal lesions and in control animals. Liver glycogen levels were determined each week for the first ten postoperative weeks and eight months postoperatively. It was found that after one week, control animals and animals with hippocampal lesions were not significantly different in liver glycogen levels. By the end of the second week the group with hippocampal lesions was significantly higher than the control animals. This variation pattern continued during the third week. By the end of the third week the animals with hippocampal ablations had reached their highest level, which remained unchanged throughout the rest of the series. No significant changes in liver glycogen levels were obtained in the control animals. Liver glycogen levels were then measured in normal rats and rats with hippocampal lesions maintained on a diurnal rhythm of twelve light hours followed by twelve dark hours. One month postoperatively, rats with hippocampal lesions had a significantly higher liver glycogen level at all time periods as compared with normal animals. Both groups of rats showed the diurnal pattern of higher levels of liver glycogen in the beginning of the light phase and lower levels of liver glycogen in the beginning of the dark phase. The observed variations may be explained in terms of alterations in known homeostatic mechanisms controlling liver glycogen levels.  相似文献   

18.
The marrow is a tissue distributed in numerous skeletal parts and works as an organ which is composed of a haemopoietic cell parenchyma and a supporting stroma. The pathophysiological mechanisms involved in the radiation-induced late effects depend mainly on the damage produced to each of these elements. Parenchymal cell damage ends with a failure of the stem cell pool to supply an adequate number of highly differentiated functional blood cells and is clinically manifested as aplastic anaemia or leukaemia. The effects of radiation on the haemopoietic stem cell can be measured by means of spleen colony forming units (CFU-S) in rodents. The self-maintaining capacity of the CFU-S was found to be lower than normal 16 weeks after a dose of 0.64 Gy. In larger animals it is only possible to measure the activity of some of the progenitor cells, estimating the number of granulocyte-macrophage colonies in culture (CFU-GM) as an indicator of stem cell changes. Their number in the blood is about 50 per cent of normal even 160 days after about 0.78 Gy. The stromal cells are also radiosensitive if measured with respect to their capacity to support long-term cell replication in vitro. Marrow fibrosis develops after single, repeated and chronic radiation exposure, and a dose of 40 Gy impairs the capacity of the marrow to support haemopoiesis.  相似文献   

19.
Ovalbumin-pulsed spleen cells were found to stimulate thymidine uptake of lymph node cells of syngeneic mice immunized with ovalbumin in complete Freund's adjuvant after treatment of spleen cells with Mitomycin C but not after heating the spleen cells at 56degrees for 30 min. Ovalbumin-pulsed spleen cells of allogeneic mice failed to stimulate the immune lymph node cells more than unpulsed cells, although a net increase in the thymidine uptake above the allogeneic stimulation was observed when free ovalbumin was added to the mixed culture. To eliminate the high background of the mixed lymphocyte reaction, F1 mice were made chimeric with bone marrow of one of the parental strains. Using lymph node cells of the immunized chimeras, the stimulation by pulsed spleen cells was much greater when antigen was presented on cells of the parental strain used for bone marrow injection than when presented on cells of the other parental strain.  相似文献   

20.
The increase of PFC per spleen and the development of hemolytic foci were examined to clarify the patterns of clonal expansion of B-lymphocytes in athymic nude mice (nu/nu) and normal littermates (nu/+) subjected to the procedure for antigenic competition between horse erythrocytes (HRBC) and sheep erythrocytes (SRBC). In normal littermates without pretreatment with HRBC, a small number of PFC and hemolytic foci of small size were detected 2-days after the challenge with SRBC. The number of PFC increased progressively from day 2 to day 4, and hemolytic foci increased in the number and size during the period. In nude mice, a small number of PVFC were detected on day 2 and the number increased only slightly from day 2 to day 4. No large hemolytic foci were detected during the period. In normal littermates subjected to the procedure for antigenic competition, the patterns of increase of PFC and development of hemolytic foci were similar to those in nude mice. In nude mice, the procedure for antigenic competition exerted almost no effect on the patterns.  相似文献   

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