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41.
安徽省鸡免疫抑制性疾病的流行病学调查 总被引:8,自引:0,他引:8
采集了安徽省6个主要养鸡地区65群鸡的185只病鸡共986份组织样品,对可引起免疫抑制性疾病的5种最常见病毒进行了PCR检测。结果,传染性腔上囊病病毒(IBDV)、鸡传染性贫血病毒(CIAV)、马立克氏病病毒(MDV)、禽白血病病毒(ALV)和网状内皮增生症病毒(REV)的群阳性率和个体阳性率分别为73.08%和40.91%、46.15%和25.95%、41.54%和17.84%、18.46%和7.57%、13.85%和4.86%,其中被检鸡之二重或多重混合感染的总阳性率为24.33%。调查结果证实,免疫抑制性疾病在安徽省的商业鸡群中普遍存在,并与鸡群疾病多而复杂、损失大相关。 相似文献
42.
论西部大开发中张掖市生态环境建设问题 总被引:3,自引:0,他引:3
张掖市长期受干旱、大风及沙尘暴影响,生态环境极为恶劣,制约着西部大开发建设进程。其存在的重要问题是:水资源匮乏,植被破坏严重,覆盖率低等;针对具体情况提出:改善水资源条件和恢复植被是张掖地区生态环境建设的重点。 相似文献
43.
XU Rui ZHANG Yun ZHANG Mei GE Zhi-ming CHEN Wen-qiang LI Xiu-chang CAI Heng ZHU Hui 《园艺学报》2003,19(5):642-644
AIM:To elucidate the relationship between the intracellular calcium concentration changes and left ventricular hypertrophy and function in the spontaneously hypertensive rats (SHR).METHODS:Intracellular free calcium concentrations were measured by Fura 2 methodology and left ventricular function quantitated by cardiac catheterization in 20 SHR aged 10, 22, and 34 weeks and 20 age-matched Wistar-kyoto (WKY) rats.RESULTS:(1) The systolic blood pressure(SBP), intracellular calcium concentrations and left ventricular mass / body weight index (LVM/BW) were significantly higher in all three age groups of SHR than the corresponding groups of WKY; (2) Compared with age-matched WKY groups, the peak left ventricular pressure descending rate(-dp/dtmax) decreased while left ventricular relaxation time constant (τ)increased significantly in SHR aged 22 and 34 weeks. The peak left ventricular pressure ascending rate(dp/dtmax) and the left ventricular contractility index were significantly increased only in the 34 weeks SHR; (3) Intracellular calcium concentrations showed a positive correlation with LVM/BW,SBP,-dp/dtmax and τ(r=0.47-0.83,P<0.01)and a negative correlation with dp/dtmax and the left ventricular contractility index (r=-0.46,P<0.05 and r=-0.81, P<0.01).CONCLUSION:Intracellular calcium overload is one of the potential mechanisms in the induction of left ventricular hypertrophy as well as of systolic and diastolic dysfunction. 相似文献
44.
AIM:To investigate the effect of cyclophosphamide(CTX) on proliferation and apoptosis of mesangial cells(GMC) of rat in vitro. METHODS:GMC proliferat ion was detected by MTT method,GMC apoptosis was examined by inverted microscopy for phase-contract and fluoroscopy and flow cytometry analysis.The levels of Fas and Bcl-2 were also detected by immunohistology. RESULTS:The proliferation of GMC were inhibited by CTX, methylprednisolone(MP), low molecular weight heparin(LMWH). Apoptosis of GMC was induced by CTX, the apoptosis rate of GMC was 8.2%, and the Fas level was increased. CONCLUSION:CTX could inhibit proliferation and induce apoptosis of GMC possibly by enhancing the Fas level. 相似文献
45.
AIM:To explore the effect of brain ischemia injury on cell proliferation and nestin expression in cortex and subependymal zone (SEZ).METHODS:Using a local brain ischemia model(MCAO), BrdU positive cells of cortex and subependymal zone (SEZ), also nestin positive cells, were observed by immunohistochemistry.RESULTS:BrdU and nestin positive cells in SEZ of MCAO rats were obviously increased. In cortex, only nestin positive cells were observed.CONCLUSION:Neural stem cells in SEZ and cortex were activated after brain ischemia, it may be related with neural recovery after brain ischemia injury. 相似文献
46.
AIM: To investigate the application of atomic force microscope (AFM) in clinic diagnosis. METHODS: Topographic images and some parameters of large range field and microstructures of erythrocytes in the blood of normal subjects, lung cancer and myelodisplastic syndrome (MDS) patients were examined by atomic force microscope. RESULTS: Many clear topographic images of many erythrocytes, single erythrocyte, and microstructure of erythrocyte membrane surface were obtained. Many erythrocytes in lung cancer patients were found to change into echinocytes. One erythrocyte had 10-20 protuberances, most of which, with a mean width of 589. 0 nm and a length of 646. 7 nm, were on the edge of cells. The protuberances on the center of echinocytes are lodged and embedded. The erythrocytes of MDS patients were biconcave in shape. Many apertures with different diameters of tens to hundreds nanometer appeared on the surface of cell membrane. CONCLUSIONS: AFM can be widely applied in clinic pathological inspection, including quantification of cells, obtainment and comparison of many parameters (such as diameter, thickness, volume, surface, surface area/volume ratio), observation of topograph of single cell, and observation and comparison of membrane surface microstructure of cells, and so on. 相似文献
47.
CAI Yun-feng MIN Jun FANG Tian-ling CHU Zhong-hua DENG Xiao-geng HE Jing-song CHEN Ji-sheng 《园艺学报》2003,19(8):1029-1033
AIM: To explore the feasibility of direct separat and selective enlargement of the bone marrow-derived liver stem cells (BDLSC) from bone marrow cells with a culture system containing cholestatic serum in vitro. METHODS: Bone marrow cells of rats were cultured with selective media containing 2%, 5%, 7% and 10% cholestatic rat serum, respectively. The BDLSC were then induced to proliferate with the addition of hepatocyte growth factor (HGF) on the firth day. BDLSC were characterized using immunocytochemistry and RT-PCR for lineage markers, glycogen staining and urea synthetic assay for functions 2 weeks later. RESULTS: Bone marrow cells were unble to form colony in the presence of 2% cholestatic serum and apopotosis appeared gradually in 7% or 10% cholestatic serum. The BDLSC survived in the medium containing 5% cholestatic serum while the other types of cells did not. The survival cells proliferated with a high speed during the second week and then formed hepatocyte-like colony-forming units (H-CFU). Cells in the H-CFU expressed the characteristic proteins of fetal hepatocytes. Furthermore, they had glycogen storage and urea synthesis functions, two of the critical features of hepatocytes. CONCLUSION: The selective micro-environment effectively selected BDLSC from the bone marrow cell, and will be a new way to provide an abundant source of donor hepatocytes for clinical cell therapy. 相似文献
48.
AIM: To confirm the existence of the endothelial progenitor cells in human cord blood and to study its differentiation and development process. METHODS: The mononuclear cells in human cord blood were isolated using lymphocyte separation solution. Then the mononuclear cells were cltured in MCDB131 containing 20% fetal bovine serum. The effects of 5 μmol/L dexamethasone, the extract from bovine brain, insulin and hypoxanine on the proliferation and differentiation of the adherent cells were observed. The morphology of the adherent cells were examined twice daily by inverted phase contrast microscope. CD34 and CD14 expression were determined by FACS. Immunohistochemistry was used to confirm the expression of factor Ⅷ. RESULTS: The proliferative endothelial progenitor cells existed within the CD34-adherent mononuclear cells of human cord blood. Dexamethasone and hypoxanine decreased the number of spindle-shaped cells and caudated cells. Bovine brain extract, insulin and FCS enhanced the number of spindle-shaped cells and caudated cells. CONCLUSION: The existence of endothelial progenitor cells within the CD34 - adherent monouclear cells of the human cord blood was observed and these cells were able to differentiate into endothelial-like cells in vitro. 相似文献
49.
50.
水稻与稻瘟病菌非亲和性互作中重要防御酶活性变化规律研究 总被引:14,自引:4,他引:14
选以CO39为背景的水稻抗稻瘟病近等基因系,与稻瘟菌生理小种ZC13(菌株97-151a)组成的3类典型非亲和性互作,以亲和性互作为对照,对各互作中过氧化物酶(POD)、苯丙氨酸解氨酶(PAL)、几丁质酶及β-1,3-葡聚糖酶的活性变化规律进行了系统研究。完全非亲和性互作C101A51/97-151a、高度非亲和性互作C101L AC/97-151a及中度非亲和性互作C104 PKT/97-151a,POD比活性接种后即开始明显升高,48h前达到高峰,升高趋势一直持续到7d完全显症时,幅度基本与各互作非亲和程度呈正相关;亲和性互作CO39/97-151a接种后40 h POD比活性才开始升高,4~6 d达到高峰,峰值也较大。3类非亲和性互作PAL比活性在接种后0 h或16 h开始较明显升高,整个互作中形成3~4个较明显的峰;亲和性互作中PAL比活性一直明显下降。3类非亲和性互作外切几丁质酶比活性接种后即开始升高,基本一直保持升高趋势,在40 h前幅度较大,并形成1~3个较高的峰;亲和性互作外切几丁质酶比活性接种后即开始大幅度升高直至完全显症,48h后幅度远高于非亲和性互作。3类非亲和性互作β-1,3-葡聚糖酶比活性在24 h内开始较明显升高,在48h前形成2~3个较明显的峰;亲和性互作在接种后β-1,3-葡聚糖酶比活性即开始升高,在48h后显著高于非亲和性互作。讨论了POD、PAL、几丁质酶及β-1,3-葡聚糖酶参与水稻抗稻瘟病的可能性。 相似文献