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1.
Li J  Bi D  Pan S  Zhang Y 《British poultry science》2007,48(6):724-728
1. An experiment was conducted to study the effect of thiram on liver antioxidant capacity and incidence of tibial dyschondroplasia in broilers. 2. One hundred and twenty Avian commercial broilers were allotted at random to three treatments: control group, low thiram group (50 mg/kg) and high thiram group (100 mg/kg). 3. Blood samples were collected to determine the activity of AST (aspartate aminotransferase). At the end of the trial, broilers were killed and liver samples were collected to determine the activity of SOD (superoxide dismutase), GSH-Px (glutathione peroxidase) and MDA (malondialdehyde) content, while the right proximal tibiotarsi were dissected in longitudinal section for assessment of tibial dyschondroplasia (TD) incidence and TD score. 4. The results showed that thiram increased the incidence of TD and TD scores, increased serum AST activity and MDA content of liver, and decreased the activity of SOD and GSH-Px in the liver. 5. They suggest that thiram causes TD in broilers by reducing liver antioxidation capability and damaging liver function; this may be one of the mechanisms by which thiram causes TD in broilers.  相似文献   
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Based on the research on the solidifiation of twin-roll casting strip,the analytical model and emulational model of nucleation,the growth of dendrity tip and colunar dendrity transformation to equiaxis dendrity (CET)of twin-roll casting strip solidification are established by means of the principle of metal solidification and modern computer emulational technology.The foundation for the emulational simulation of twin-roll casting strip solidification structure is laid.  相似文献   
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This paper introduces the modeling of Unified Modeling Language with use case diagram and active diagram based on Rational Unified Process for Equipment Managemet Information System. It discusses the modeling mechanism and character of UML and develops the Computer Equipment management Information System Based Web using Rational Rose of UML CASE Tool. First, it is describe the authors how to analyze the structure of organize and build the model of structure organize. Second, they abstract the workflow of main operation in organize and build workflow model by active diagram. Finally, they abstract actor, use case with case diagram and finish the requirement model.  相似文献   
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Brick masonry wall-beams in frames are girders,carrying brick masonrywalls in buildings with only one or two storied reinforced concrete frames atthe bottom of it.How to anaIyse and design such an element is an outstand-ing problem.In this case,there are no analytical and designing rules in thestate code in force.Therefore,designers have to seek other methods,in whichmost are very conservative and expensive.In order to change this case,thispaper provides an analytical and practical mathod for designers.  相似文献   
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The efficacy of Mycoplasma hyopneumoniae oral vaccine was investigated in microsphere dosage form. A co-spray drying process was used to apply an encapsulating material, Eudragit L30 D-55, to microspheres containing Mycoplasma hyopneumoniae antigens. The microspheres were generally effective (>93%) with protein release at pH 7.4, but almost none were released at pH 1.2, for 3 hr in an in vitro dissolution test. An SPF-swine model was used to evaluate the effectiveness of the microspheres as an oral vaccine, and the related immune responses. The serum's systemic IgG against M. hyopneumoniae was evoked by ELISA analysis, after a 2nd immunization of all pigs. The vaccinated groups' mean lesion score was significantly lower after the Mycoplasma hyopneumoniae challenge than that of the nonvaccinated/challenged groups (P<0.05). This study strongly suggests that the oral microspheres vaccine prepared by a co-spray drying method can provide effective protection against M. hyopneumoniae infection in pigs.  相似文献   
7.
Thirty-three cases of enzootic bovine leukosis (EBL) and 14 cases of sporadic bovine leukosis (SBL) were examined by immunohistochemistry using 6 monoclonal antibodies against leukocyte differentiation molecules of bovine leukocytes. There were 17 cases of B-1a cell type, 10 cases of B-1b cell type and 6 cases of B-2 cell type in EBL, and 5 cases originating from B cells (B-2 cell type) and 9 cases originating from immature T cells in SBL. The average age for the EBL cases of B-1a cell type was 8.6 years, B-1b cell type was 6.5 years, and of B-2 cell type was 4.5 years. In cases of SBL, immature T cell type patients were younger than B-2 cell type ones. The lymphoma originating from B cells differed from that originating from T cells in morphology. In T cell tumors, the nucleus of tumor cells was round, the edge of the cytoplasm obvious, and tumor cells were sporadically present and proliferated. When compared with T cells, the region among B cells was obscure. But, there was no relation between phenotype and the histologic classification of tumor cells. In EBL, beyond the lymph node, tumors of B-1a and B-1b types had developed in the heart and abomasum, and those of the B-2 type tended to occur in liver. In SBL, B-2 type and T type cells formed tumors in the liver, kidney, thymus, and one case of T-cell type tumor formed on the skin. We would like to propose a new classification of bovine leukosis as EBL, calf type B-cell lymphoma, juvenile T-cell lymphoma and skin type T-cell lymphoma.  相似文献   
8.
OBJECTIVE: To evaluate the efficacy of an orally administered vaccine of Mycoplasma hyopneumoniae that was prepared by spray drying or solvent evaporation. ANIMALS: Thirty 6-week-old, crossbred, specific-pathogen-free (SPF) pigs. PROCEDURE: Pigs were randomly allocated into 5 groups and housed in an SPF facility. Pigs in 2 groups (groups AQ and CAP) were fed M hyopneumoniae enteric-coated vaccine on days 0, 10, and 20. A third group (group IM) received an IM injection of M hyopneumoniae vaccine with aluminium hydroxide as an adjuvant on days 0, 10, and 20. The last 2 groups (non-vaccinated-challenged [NV-C] and nonchallenged [NC]) were fed a sham treatment. All 24 pigs in groups AQ, CAFP IM, and NV-C were challenge exposed with 5 ml of a 10% pneumonic lung suspension administered on day 40 via intubation of the trachea. All pigs were slaughtered and the lungs removed and examined for lesions on day 68. RESULTS: In vitro studies indicated that these 2 microencapsulation techniques formed an effective shell and protected mycoplasmal antigen from gastric acid. Results of inoculation and challenge tests indicated that microencapsulated M hyopneumoniae were sufficiently potent to induce an immune response and provide good protection. CONCLUSIONS AND CLINICAL RELEVANCE: Orally administered microencapsulated M hyopneumoniae vaccines induced an immune response and reduced the severity of lung lesions in challenge-exposed pigs. Results suggest that this novel method can be applied to other antigens, because the spray-drying process yielded an orally administered M hyopneumoniae vaccine that induced a good immune response.  相似文献   
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This study examined the growth inhibitory effects of structurally related polymethoxylated flavones in human cancer cells. Here, we report that 5-hydroxy-3,6,7,8,3',4'-hexamethoxyflavone (5-OH-HxMF) induces growth inhibition of human cancer cells and induction of apoptosis in HL-60 cells through modulation of mitochondrial functions regulated by reactive oxygen species (ROS). ROS generation occurs in the early stages of 5-OH-HxMF-induced apoptosis, preceding cytochrome c release, caspase activation, and DNA fragmentation. The changes occurred after single breaks in DNA were detected, suggesting that 5-OH-HxMF induced irreparable DNA damage, which in turn triggered the process of apoptosis. Up-regulation of Bax was found in 5-OH-HxMF-treated HL-60 cells. In addition, a caspase-independent pathway indicated by endonuclease G also contributed to apoptosis caused by 5-OH-HxMF. Antioxidants suppress 5-OH-HxMF-induced apoptosis. 5-OH-HxMF markedly enhanced growth arrest DNA damage-inducible gene 153 (GADD153) protein in a time-dependent manner. N-acetylcysteine (NAC) and catalase prevented up-regulation of GADD153 expression caused by 5-OH-HxMF. These findings suggest that 5-OH-HxMF creates an oxidative cellular environment that induces DNA damage and GADD153 gene activation, which in turn helps trigger apoptosis in HL-60 cells. Meanwhile, ROS were proven an important inducer in this apoptotic process. The C-5 hydroxyl on the ring of 5-OH-HxMF was found to be essential for the antiproliferative and apoptosis-inducing activity. Our study identified the novel mechanisms of 5-OH-HxMF-induced apoptosis and indicated that these results have significant applications as potential chemopreventive and chemotherapeutic agents.  相似文献   
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