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22.
番鸭在南京地区进行冬、夏两批饲养,均有较强的适应性。试验结果表明:冬、夏两 批饲养的番鸭只平均重量差异不显著(P>0.05)。夏季与冬季的料重比分别为1:2.62和1: 3.07,冬季饲养的鸭子饲料利用率低,料重比大于夏季。冬季在塑料大棚中饲养番鸭精饲料减 少1/3,添加青粗饲料能达到同样的增重效果。温度与增重无相关关系,相对湿度与番鸭的增 重呈负相关(P<0.01)。鸭舍内平均温度在11.05℃-30.93℃之间,相对湿度在76.28%以 下,番鸭能正常生长发育。环境温度在9.8℃以下,番鸭的生长发育受阻,饲料利用率降低。相 对湿度在77%以上,其增重受到影响。特别在低温高湿的环境中,严重地影响番鸭的生长。在 相同的饲养期内,周平均温度9.8℃,平均相对湿度91%,番鸭周平均增重22 g,周平均温度 27.42℃,平均相对湿度71.29%,番鸭周平均增重355 g,相差333 g(P<0.01)。 相似文献
23.
AIM and METHODS: Total RNA was extracted from 6th rat subcultured pulmonary artery smooth muscle cells(PASMC) exposed to continual chronic hypoxia or normoxia and the effects of chronic hypoxia on the changes of Kv1.3,Kv2.1,Kv3.1 mRNA in cultured PASMC induced by acute hypoxia were studied by semiquantitative RT-PCR in vitro. RESULTS:①Kv1.3,Kv2.1,Kv3.1 genes were found to be expressed in PASMC of rats exposed either to hypoxia or normxia.②The expression of Kv2.1 and Kv3.1 in 6th subcultured of PASMC in normaxia group could be upregulated by exposure to acute hypoxia,the levels of Kv2.1 and Kv3.1 mRNA were significantly increased from 0.646±0.092, 0.782±0.104 to 1.059±0.134, 0.985±0.116,respectively (P<0.01,n=5). ③PASMC cultured continuously in chronic hypoxia for 6 subcultures and then exposed to normoxia for 12 h,thereafter the expression of Kv2.1 and Kv3.1 were downregulated by acute hypoxia for 6 hours.The level of Kv2.1 mRNA was significantly decreased from 1.008±0.117 to 0.649±0.097 (P<0.01,n=5). CONCLUSION:Kv2.1,Kv3.1 genes might be oxygen sensitive genes.Chronic hypoxia might change the response of these Kv genes of PASMC to acute hypoxia and down-regulate its expression,which might probably decrease the role of Kv in HPV. 相似文献
24.
AIM: To examine the expression and distribution of tumor necrosis factor-α (TNF-α), tumor necrosis factor receptor I (TNFR I) and apoptosis in oral lichen planus, and evaluate their roles and relation in the oral lichen. METHODS: Immunohistochemical technique and TUNEL were employed to study the expression of TNF-α, TNFR I and apoptosis in 50 cases of oral lichen planus and 10 normal oral mucosa specimens. RESULTS: Compared with the normal control group, TNF-α expression was upregulated in mononuclear cells in lamina propria and decreased in keratinocytes in oral lichen planus lesion (P<0.05). On the contrary, TNFR I expression was increased in keratinocytes and decreased in lamina propria in oral lichen planus lesion (P<0.05). The increased apoptosis index in keratinocytes and the decreased apoptosis index in lamina propria were found in oral lichen planus (P<0.05). CONCLUSION: The accelerated apoptosis of keratinocytes and the inhibition of lymphocytes apoptosis may contribute to the formation and progression of oral lichen planus. 相似文献
25.
选用中华硬蜱105kD柱层析纯化抗原对新西兰兔进行免疫接种,再用二棘血蜱进行叮咬,并与单纯二棘血蜱叮咬组和佐剂对照组进行对比,以探讨不同种属硬蜱之间的交叉免疫抗性。结果显示:单纯二棘血蜱叮咬组吸血量为181 3±44 3mg,而二棘血蜱叮咬由中华硬蜱105kD纯化抗原免疫接种组和佐剂对照组新西兰兔后其吸血量分别为102 1±25 3mg和168 5±40 9mg,纯化抗原免疫接种组较单纯二棘血蜱叮咬组和佐剂对照组吸血量分别下降43 7%和39 4%(P<0 01)。同时,纯化抗原免疫接种组也较单纯二棘血蜱叮咬组和佐剂对照组产卵量有显著下降。该研究结果表明中华硬蜱和二棘血蜱之间存在着交叉免疫反应。 相似文献
26.
DU Yi-mei TANG Ming LIU Chang-jin HONG Zhi-gang KE Qin-mei DI Jiu-fang LUO Hong-yan HU Mou-xian HU Xin-wu XI Jiao-ya TANG Bi Jurgen Hescheler 《园艺学报》2004,20(9):1537-1541
AIM: To determine the role of Kv1.2, Kv1.5, Kv2.1 in the hypoxia pulmonary vasoconstriction (HPV). METHODS: Male Wistar rats were divided into two groups: normoxic group and hypoxic group. The single smooth muscle cell was obtained from pulmonary artery of Wistar rats with acute enzymatic digestion method. The conventional whole-cell patch clamp technique was used to record the resting membrane potential (Em) and the potassium currents of voltage-gated potassium channel (IKv) in rat pulmonary arterial smooth muscle cells (PASMC). Intracellular application of Kv1.2/Kv1.5/Kv2.1 antibodies (1∶125) was conducted through the whole-cell patch clamp system. RESULTS: ① Em of PASMC was depolarized after 24 h hypoxia compared with that of control cells . IKv of PASMC was decreased after 24 h hypoxia, . ② The mixture of Kv1.2/Kv1.5/Kv2.1 antibodies depolarized Em and inhibited IKv in PASMC from normoxic rat, whereas the mixture of Kir2.1/Kir2.3/Kir4.1 antibodies had no effects on them. ③ The mixture of Kv1.2/Kv1.5/Kv2.1 antibodies and the mixture of Kir2.1/Kir2.3/Kir4.1 antibodies had no effects on IKv and Em from rats hypoxic for 24 h. CONCLUSION: Kv1.2, Kv1.5, Kv2.1 might be oxygen sensitive potassium channels which mediated HPV. 相似文献
27.
Chloride channels distribute widely in the body, and participate in many physiological actions and regulatory processes. Based on their physiological roles and molecular structures, six kinds of chloride channels have been identified: (1) The chloride channels family; (2) Cystic fibrosis transmembrane conductance regulator; (3) Swelling-activated chloride channels; (4) Calcium-activated chloride channels; (5) The p64 (CLIC) gene family; (6) γ-aminobutyric acid and glycine receptors. The chloride channels do exist in platelets, and their appearances are dependent on the presence of intracellular calcium. Blocking agents of chloride channels inhibit the thrombin-activated platelet aggregation and the elevation of the intracellular calcium concentration in a dose-dependent manner. It is suggested that chloride channels play a role in the activation of platelets. In addition, chloride channels act on both the cell volume regulation and the intracellular pH regulation in platelets. 相似文献
28.
猪多杀性巴氏杆菌的分离鉴定及生物学特性研究 总被引:17,自引:2,他引:17
用PCR方法配合生化鉴定,从有肺炎症状猪的肺脏及进行性萎缩性鼻炎(Progressive atrophic rhinitis,PAR)症状猪的鼻拭子中分离出66株多杀性巴氏杆菌(Pasteurella multocida,Pm)。然后做了药敏试验,并用PCR方法对这66株Pm进行分型及毒素基因的检测,用豚鼠皮肤坏死试验及小鼠致死试验对产毒素多杀性巴氏杆菌(Toxigenie Pasteurella multocida,T^ Pm)进一步鉴定。结果显示PCR鉴定与生化鉴定Pm结果完全一致;PCR分型表明有46株为D型Pm,18株为A型:Pm,1株为B型Pm,1株无法定型;有8株用PcR检测为T^ Pm;豚鼠皮肤坏死试验及小鼠致死试验对这8株T^ Pm的进一步鉴定也表明均为产毒素菌株。所鉴定的8株T^ Pm都为D型,都分离于有严重PAR症状的猪。 相似文献
29.
鸡呼吸道传染病基因芯片诊断方法的建立 总被引:4,自引:0,他引:4
随着养禽业集约化程度的不断提高,鸡呼吸系统疾病的发生呈逐年上升趋势.而且大多数的呼吸道疾病不是单一病原感染,而是多种病原混合感染,从临床上难以及时鉴别诊断,延误防治时机,从而给养禽业造成巨大的经济损失.因此,禽呼吸道疾病已经成为生产和研究中的一类重要疾病.目前,禽呼吸系统疾病的诊断方法主要有病毒分离、血凝(HA)、血凝抑制(HI)、琼脂扩散、ELISA、PCR等,但是传统的检测方法灵敏度较低,而且当病原发生变异或感染禽处在潜伏期时会造成误诊.PCR方法每次只能检测一种病毒,费时费力.采用基因芯片的方法可以快速、准确地同步检测多种病原体,且需要样品量少、灵敏、特异、快速、费用低廉,将生物芯片技术用于禽呼吸道疾病诊断意义重大. 相似文献
30.
To study the effect of luteolin on blood indexes,liver and kidney in mice with acute mercury poisoning,28 mice were randomly divided into four groups:Control group (intraperitoneal injection 0.9% saline),luteolin group (lavage 100 mg/kg luteolin),mercuric chloride group (intraperitoneal injection 4 mg/kg mercury chloride) and mercury chloride+luteolin group (intraperitoneal injection 4 mg/kg mercuric chloride,lavage 100 mg/kg luteolin).The activities of ALT in serum,AST,CREA and BUN contents,blood WBC,RBC,HGB content and GSH and MDA contents of liver tissue were detected.Morphological changes of liver and kidney tissues were observed.The results showed that compared with the control group,the activities of ALT and AST of mercuric chloride group were extremely significantly increased (P < 0.01),serum CREA,BUN,blood WBC and liver tissue MDA contents were significantly increased (P < 0.05) while blood RBC,HGB and liver tissue GSH contents were significantly decreased (P < 0.05).Liver,kidney pathological changes were obviously.Compared with mercuric chloride group,the activities of ALT,AST in serum,CREA,BUN,blood WBC and liver tissue MDA contents of mercuric chloride+luteolin group were significantly decreased (P < 0.05),while blood RBC,HGB and liver tissue GSH contents were significantly elevated (P < 0.05).Liver,kidney pathological changes were attenuated obviously.The poisoning were characterized by inflammation and the occurrence of anemia when acute mercury poisoning occurred,liver and kidney showed different degrees of injury in mice.Luteolin could reduce the toxic effects of acute mercury poisoning on blood,liver and kidney. 相似文献