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41.
42.
AIM:To investigate the role of calcineurin (CaN) in airway remodeling in guinea pig model of asthma.METHODS:Male guinea pigs were randomly divided into three groups: control, asthma group and CsA group. The following parameters were measured: 1. The protein content, cell count and differential count of BALF; 2. The amount of [3H]-TdR incorporation into central airway smooth muscle; 3. The mean thickness of airway wall and airway smooth muscle of small airwaysl; 4.CaN activity of trachea and lung tissue.RESULTS:1. The protein content, cell count and eosinophil of BALF in CsA group were 46%, 51% and 60% lower than those in asthma group, respectively (P<0.01); 2. [3H]-TdR incorporation in CsA group was 22% lower than that in asthma group (P<0.05);3. The mean thickness of airway wall and airway smooth muscle were 34% and 37% less in CsA group than those in asthma group, respectively (P<0.01); 4. CaN activity of lung tissue and trachea were 52% and 44% lower in CsA group than those in asthma group, respectively (P<0.01).CONCLUSION:CsA reduced airway remodeling in guinea pig model of asthma, indicating the role of CaN in the airway remodeling.  相似文献   
43.
AIM: To examine the expression of alpha-smooth muscle actin in scar tissue, and observe the phenomenon of apoptosis and its involvement in the process of pathological scarring and the presence of myofibroblasts or absence of cell in the dermis. To investigate the potential role of reparative cell apoptosis in hyperplastic scar formation. METHODS: The samples of scar were obtained from post-burn patients undergoing plastic operation in our burn unit recently, and the samples of control came from skin donor site of the same patient correspondingly. TUNEL assays were performed to evaluate the number of apoptotic cells in scar versus normal skin. In situ hybridization and immunohistochemistry staining technique were employed to determine the expression of different dermis cells markers in scar tissue and normal skin. RESULTS: There existed evident difference in apoptotic cells in the dermis between scars tissue and normal human skin. The expression positive cells were much more in hyperplastic scars than that in normal human skin; the apoptotic cells of proliferative stage were slight more than that of mature stage. However, in proliferative stage, the number of apoptotic cells was higher for the combination of hyperplastic scar than normally healed flat scars. But in mature stage, no obviously difference was detected between hyperplastic scar and normally healed flat scar. The monoclonal anti-α smooth muscle actin (ASMA) expression was significantly stronger in proliferative stage than that of mature stage. CONCLUSIONS: With reconstitution of dermal tissue, myofibroblasts containing alpha-SM actin disappear under normal wound healing, probably as a result of apoptosis. The myofibroblast play a critical role in wound closure and in the pathologic sequelae of healing.  相似文献   
44.
引进扁桃的品质特性观察   总被引:6,自引:0,他引:6  
从美国引进的3个扁桃品种,用山桃作砧木,在陕西渭北地区生长旺盛,苗木栽植第3年开始开花结果,5年生平均株产1.78~2.03kg。扁桃3月中下旬开花,果实前期发育较快,至5月中旬果径生长量占总量的80%~90%,后期增长缓慢。Nonpareil品种7月25日~8月5日成熟,Mission品种9月11日~9月15日成熟。成熟种仁饱满,外观品质较好。种仁含粗脂肪49.62%~52.49%,含粗蛋白20.9%~29.0%,含VB11.8~1.91mg/kg,VB24.08~4.62mg/kg。氨基酸及钙、镁等元素含量也较丰富,与我国新疆扁桃主产区产品营养含量相近似。  相似文献   
45.
田景花  张红  李明  王梅 《园艺学报》2003,30(6):728-730
 采用免疫胶体金电镜技术对黄瓜幼叶叶肉细胞中的钙调素(CaM)进行定位。结果表明:适温下生长的黄瓜幼苗叶肉细胞中的CaM主要分布于细胞核和叶绿体内,细胞核中CaM主要存在于染色质和核仁上,叶绿体中CaM主要存在于类囊体膜上;线粒体中也有一定量的CaM分布;细胞质、液泡、液泡膜及质膜上只有少量CaM存在;而细胞壁和细胞间隙却很难发现显示CaM存在的金颗粒。  相似文献   
46.
兽用抗寄生虫药物新剂型及其新技术的研究进展   总被引:8,自引:1,他引:8  
兽用抗寄生虫药物由于使用频繁,其给药技术研究一直备受重视.目前,兽用抗寄生虫药物新剂型和新技术的研究主要集中在缓释控释制剂和脂质体制剂,其次是透皮给药系统、微囊、微球、环糊精包合物、固体分散体等.但这些新剂型和新技术大多还处于研究阶段,在处方设计或制剂工艺方面都还存在一些问题,今后应加强这些新剂型的工艺和技术研究,以真正发挥这些新剂型的优点.  相似文献   
47.
建立了同时测定复方甲硝唑片中甲硝唑和维生素B6含量的离子对HPLC方法.采用ODS色谱柱,流动相为磷酸二氢钾和庚烷磺酸钠水溶液(每1L中含磷酸二氢钾13.6 g与庚烷磺酸钠1.0 g)-甲醇-三乙胺(85∶15∶0.4),用磷酸调pH至2.8;检测波长290 nm,以峰面积计算,外标法定量.甲硝唑和维生素B6的线性范围分别为100~300 μg/mL(r=0.999 9)和5~50 μg/mL(r=0.999 9);平均回收率分别为100.2%(RSD=1.0%,n=6),99.8%(RSD=1.2%,n=6).该方法测定结果准确,操作简便,回收率高.  相似文献   
48.
外来入侵种的危害与防治对策   总被引:1,自引:0,他引:1  
外来入侵种对当地的自然生态系统结构和功能以及生物多样性都有着深远的影响,而且可能对地方的生态环境和经济造成严重危害。四川已经成为遭受外来入侵种威胁的省份之一,全省现有20多个外来入侵种。为了防止外来入侵种的泛滥,应当建立外来物种的引入评价机制,慎重进行有意引种;加强口岸管理,防止外来入侵种通过贸易途径无意引入,同时采取措施控制已经产生危害的外来入侵种。  相似文献   
49.
AIM: To investigate the role of NF-κB/IκB signal pathway in the regulation of cyclooxygenase-2 (COX-2) expression in human mesangial cells (HMC). METHODS: The PGE2 concentration in supernatants of HMC was measured by radioimmunoassay. COX-2 mRNA and protein expression were determined by RT-PCR and Western blot. Electrophoretic mobility shift assay (EMSA) and Western blot were used to detect the activity of NF-κB and degradation of IκB. RESULTS: IL-1β significantly upregulated COX-2 expression and PGE2 production in HMC. Significant up-regulation of NF-κB activation, nuclear translocation of p65 subunit, and degradation of IκB α and IκB β were observed in IL-1β-induced HMC. CONCLUSION: Expression of COX-2 in IL-1β-induced HMC is mediated by NF-κB/IκB signal pathway.  相似文献   
50.
AIM: To investigate the role of nitric oxide synthase (NOS), soluble guanylyl cyclase (sGC) and protein kinase C (PKC) signaling in tumor necrosis factor-α (TNF-α)-induced cardioprotection against hypoxia/reoxygenation (H/R) injury. METHODS: Neonatal rat ventricular myocytes were pretreated with TNF-α or sodium nitroprusside (SNP) or L-arginine (L-Arg), respectively, for 12 h and then subjected to continuous hypoxia for 12 h, followed by reoxygenation for 6 h. The manganese superoxide dismutase (Mn-SOD) activity of the cells was measured after H/R. Myocyte injury was determined by the release of lactic dehydrogenase (LDH). RESULTS: TNF-α (105 U/L) significantly increased the Mn-SOD activity and decreased release of LDH from ventricular myocytes. The cardioprotection against H/R injury was induced by the pretreatment with SNP (5 μmol/L) or L-Arg (5 mmol/L), which was blocked by ODQ (10 μmol/L), the specific sGC inhibitor, and Chel (5 μmol/L), the specific PKC inhibitor. Pretreatment with L-NAME (100 μmol/L), ODQ, Chel, antoxidant 2-MPG (400 μmol/L) or tyrosine kinase inhibitor genistein (50 μmol/L) attenuated the increased Mn-SOD activity and reduced LDH level induced by TNF-α. CONCLUSION: The results suggest that NO may play a role in TNF-α-induced cardioprotection, which is mediated by sGC and PKC.  相似文献   
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