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71.
Ten multiparous lactating sows were used to investigate whether intramammary infusion of lipopolysaccharides (LPS; Escherichia coli 0111:B4; 2.0 μg/kg of body weight) would affect the circulating concentrations of Ca, P, 25‐hydroxyvitamin D (25‐OHD), tumour necrosis factor‐α (TNF‐α), interleukin‐6 (IL‐6) and cortisol. The sows were randomly allotted to either control group (control) or LPS‐treated group with five individuals per group and were infused with either physiological saline solution or LPS solution. The rectal temperature and udder quarter appearance were recorded at 0 (just before infusion), 1, 3, 7, 12 or 24 h after infusion. Blood samples were taken at 0, 1, 3, 7, 12 or 24 h after infusion. Before infusion, the rectal temperatures of all sows were below 39.2°C. At 3 and 7 h after infusion, the sows in the LPS group had a rectal temperature over 39.4°C. At 24 h after infusion, the rectal temperatures returned to pre‐infusion levels. Serum Ca and P concentrations in the LPS group decreased (P < 0.05) after LPS infusion compared with the control group at 1 h after infusion. No significant differences (P > 0.05) in the concentrations of 25‐OHD were observed between groups control and LPS at any sampling time. Increased (P < 0.01) concentrations of serum TNF‐α, IL‐6 and cortisol were observed in the LPS group compared with the control group at 3 and 7 h after infusion respectively. In conclusion, the elevation of serum concentrations of TNF‐α, IL‐6 and cortisol and the alterations of circulating concentrations of Ca and P following LPS infusion indicate that the immune system has been activated and immune activation may affect macromineral homeostatic regulation, which might have important implications for metabolic health of lactating sows. Lowered serum Ca and P following immune activation also shows a causative mechanism whereby immune activation increases the risk of secondary disorders such as mastitis‐metritis‐agalactia syndrome. However, immune activation did not affect circulating concentrations of vitamin D metabolites.  相似文献   
72.
目的 探讨环氧合酶 (COX) 2与肝细胞癌血管形成的关系。方法 利用免疫组织化学、Westernblot方法检测 48例肝癌组织中COX 2和血管内皮生长因子 (VEGF)蛋白及逆转录 聚合酶链反应法 (RT PCR)检测COX 2和VEGFmRNA的共表达 ,对共表达COX 2和VEGF蛋白和mRNA的肝癌组织进行微血管记数。结果 免疫组织化学检测中 ,48例肝癌组织 3 6例共表达COX 2和VEGF蛋白。类似结果见于蛋白电泳分析。RT PCR显示 ,48例肝癌组织 3 6例共表达COX 2mRNA和VEGFmRNA。两者之间的表达明显相关 (γ =0 .845 )。共表达COX 2和VEGF蛋白和mRNA的肝癌组织中 ,平均微血管数 (5 6.8± 17.5 )个 ,明显高于阴性表达组。结论 COX 2可能与肝细胞癌的血管形成有关 ,且其作用之一可能是通过上调VEGF通道来发挥的  相似文献   
73.
Objective To investgate the effects of TGF β 3 on rat hepatic fibrosis. Methods The TGF β 3 cDNA was cloned into rAAV2 vector. Rats were randomly divided into four groups: normal control group, model group, negative control group and TGF β 3 group. Hepatic fibrosis was induced by hypodermic injection of 40% CCI4. Recombinant AAV2-TGF β 3 viral particles were injected via the vena caudalis one week before CCh treatment. Rats were executed 8 weeks after CCI4 treatment, global histological change was observed after HE staining, the distribution of the collagen fibers was observed after masson staining, his-tochemistry was done to observe the expression of collagen Ⅰ; The positive area rate of the collagen fibers and the average optical rate of collagen Ⅰ were quantified. Results HE staining indicated that collagen fibers were reduced in the TGF β 3 group. Masson staining shown that the collagen fibers were distributed around the blood vessel, in the portal area and disse space. Compared to the model group (13.2%±2.2%) and negative control group (12.3%±1.5%), the collagen fibers in liver tissues of TGF β3 group (7.7% ± 1.5%) were significantly decreased (q = 9.456, P < 0.01; q = 8.217, P < 0.01). Histochemistry indicated that the collagen fibers of liver tissues of TGF 15 3 group (0.185±0.033) were significantly higher than those in the model group (0.252±0.042) and the negative control group (0.230±0.029), (q = 6.228, P < 0.01; q = 4.346, P < 0.01). Conclusion TGF β 3 alleviates the damage to hepatic cell and the level offibrosis in CCI4 treated rats and inhibits the expression of collagen Ⅰ.  相似文献   
74.
Polystyrene-bound metal [2,9 or 2,10 (or 2,16 or 2,17) bis(3,4-dicarboxybenzoyl)]phthalocyaninates were synthesized by Friedel-Crafts reaction of polystyrene with the corresponding metal phthalocyaninates. Co(II) and Cu(II) [2,9 or 2,10 (or 2,16 or 2,17) bis(3,4-dicarboxybenzoyl)]-phthalocyaninate (PS-CodaPc and PS-CudaPc) contained 0,13 mmol · g?1 (12,4 wt.-%) and 0,13 mmol · g?1 (12,8 wt.-%) of CodaPc and CudaPc, respectively. They were soluble in N,N'-dimethylformamide, but only partially soluble in chloroform, tetrahydrofuran (THF), dimethyl sulfoxide, N-methyl-2-pyrrolidone, and pyridine. The THF extracts contained 0,12 mmol · g?1 (11,4 wt.-%) and 0,18 mmol ? g?1 (17,2 wt.-%) of PS-CodaPc and PS-CudaPc, respectively. The thermal stability of the polymers was studied using thermogravimetric and differential thermal analysis in nitrogen and synthetic air atmosphere. The contents of MdaPc(M: metal) in THF-extracted polymers calculated from the data of residue in thermogravimetric analysis are 0,12 mmol · g?1 for PS-CodaPc and 0,19 mmol · g?1 for PS-CudaPc. In addition, the sensitive properties of the polymers towards toxic gases were also investigated by quartz microbalance transducers. The results show that the quartz microbalance sensors coated with both polymers were sensitive to NO2 and chlorinated hydrocarbons, i.e. chloroform and perchloroethylene. The sensitivity to NO2 was 6,53 · 10?7 m3 · mL?1 · s?1 for PS-CodaPc and 1,90 · 10?6 m3 · mL?1 · s?1 for PS-CudaPc, and that to chloroform and perchloroethylene was 2,33 · 10?8 and 4,60 · 10?8 m3 · mL?1 · s?1, respectively, for PS-CodaPc and 4,79 · 10?8 and 9,51 · 10?7 m3 · mL?1 · s?1 for PS-CudaPc.  相似文献   
75.
本文采用1:3病例对照研究方法,对甾体避孕药的使用与血栓栓塞性疾病(急性心肌梗塞、脑栓塞、脑血栓形成和深静脉血栓形成)间的关联进行多因素分析。结果提示在我国广泛应用的甾体避孕药(主要为国产Ⅰ号避孕药)并不增加血栓栓塞性疾病的危险性。用药和停药时间的长短与血栓栓塞性疾病的发生无关,并与高血压病之间亦不存在协同作用。  相似文献   
76.
医疗纠纷指发生在医疗机构与患者及其亲属间因诊疗护理行为而引起的争议。其涉及的人员广泛,包括:临床医生、护士、药师;内容多样:诊断、治疗(手术和其他治疗)、用药、护理等都可能涉及。随着人们生活水平的提高,医疗制度改革的不断深入,国民维权意识的提高,人们对于医疗与药品  相似文献   
77.
目的:探讨颅脑外伤严重程度及CT征象与预后的关系,并探讨CT复查的最佳时间及临床意义。方法:回顾性分析80例颅脑外伤的严重程度与初次CT征象的关系,统计分析复查CT发现新病变的数目、程度及时间。结果:颅脑外伤的严重程度与初次CT征象符合率为92.5%(74/80)。外伤后即刻昏迷、CT显示重度复合伤、脑干损伤或弥漫性脑白质损伤的病死率达70.0%(21/30)。1~3d复查CT发现迟发性病变80个,4—7d21个,7d后8个。结论:临床病情与CT征象变化对判断预后有重要意义,颅脑外伤后3、7d是复查CT的最佳时机,出现病情变化应随时复查。  相似文献   
78.
目的 探讨疝环充填式无张力修补术治疗腹股沟疝的经验并评价其临床价值.方法 回顾总结2000年1月至2007年6月疝环充填式无张力修补术治疗腹股沟疝262例临床资料,其中伴随高血压、冠心病、糖尿病、慢性呼吸系统疾病、便秘、前列腺肥大等238例,占90.8%.结果 全组均治愈,手术时间平均41分钟,无切口感染,术后4~7天出院,平均住院5天,随访3~64个月,疝复发1例,为0.4%.结论 该方法操作简便,符合腹股沟区生理解剖特点,强调对高龄患者的术前准备,强调严格的无菌操作,强调充填物放置到位和充填后修补到位是避免术后复发的关键.  相似文献   
79.
锁骨骨折是临床常见的一种骨折,约占全身骨折的2.6%~5.98%[1.2].喙突外侧部分的骨折约占总数的10%.近年来为解决锁骨远端骨折的解剖复位及早期关节功能康复锻炼问题,人们设计了各种各样的内固定物.本院自2003年8月起,采用肩锁钩钢板内同定治疗25例锁骨远端骨折,现报告如下.  相似文献   
80.
无症状性炎性前列腺炎对血清PSA、fPSA的影响   总被引:3,自引:0,他引:3  
目的 探讨无症状性炎性前列腺炎(NIH分类Ⅳ型)对血清PSA、fPSA的影响。方法 对比分析36例NIH分类Ⅳ型、42 例有症状性慢性前列腺炎(NIH分类ⅢA型)患者以及22例健康对照组的血清PSA、fPSA、fPSA/tPSA之间的差异。结果 血 清PSA、fPSA、fPSA/tPSA在Ⅳ型和ⅢA型前列腺炎患者间差异无显著性(P>0.05),但与正常对照组比较差异有显著性(P< 0.01)。结论 NIH分类Ⅳ型前列腺炎可引起血清PSA、fPSA升高。对无症状、高血清PSA患者行前列腺活检前,应考虑到患 Ⅳ型前列腺炎的可能。  相似文献   
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