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991.
为了探究丹皮酚对急性胰腺炎(acute pancreatitis,AP)小鼠氧化损伤的影响,本试验选取50只SPF级雄性小鼠,随机分成5组,每组10只,分别为空白对照组、AP模型组和丹皮酚高、中、低剂量组。丹皮酚组小鼠分别灌胃100、50和25 mg·kg-1丹皮酚,同时空白对照组和AP模型组小鼠给予等体积生理盐水。连续灌胃5 d后,采用20% L-精氨酸腹腔注射AP模型组和不同剂量丹皮酚组小鼠,6 h后采集各组小鼠血清测定氧化指标(MDA、SOD),取小鼠胰腺组织肉眼观察病理学变化,并制作胰腺组织髓过氧化物酶(myeloperoxidase,MPO)免疫组化切片,观察其组织病理学变化和MPO的分布及表达。采用荧光定量PCR检测各组胰腺组织中HO-1、Keap1以及Nrf2 mRNA表达水平,采用Western blot检测HO-1、Keap1以及Nrf2蛋白表达量。结果发现,不同剂量的丹皮酚极显著降低急性胰腺炎氧化损伤下小鼠机体的MDA含量,并极显著提高抗氧化酶SOD活力(P<0.01);免疫组化结果显示,高、中剂量丹皮酚有效减少MPO表达;与AP模型组相比,中、高剂量组丹皮酚极显著升高HO-1和Nrf2 mRNA及蛋白表达(P<0.01),低剂量组丹皮酚极显著提高Nrf2 mRNA及蛋白表达(P<0.01),不同剂量组丹皮酚极显著降低Keap1 mRNA和蛋白表达(P<0.01)。综上,丹皮酚可能通过激活Nrf2/HO-1信号通路缓解L-精氨酸诱导的小鼠急性胰腺炎氧化损伤,研究结果为急性胰腺炎发病机制及相关药物的研发提供理论参考。  相似文献   
992.
Magnetic resonance imaging of two suspected cases of global brain ischemia   总被引:1,自引:0,他引:1  
Objective: To describe the clinical findings and magnetic resonance imaging (MRI) characteristics of two animals with suspected global brain ischemia (GBI). Series summary: Two brachycephalic animals (Persian cat and Boston terrier) presented for altered mentation, blindness, ataxia, and seizures after being anesthetized. Common to both anesthetic protocols was ketamine. Clinically, the neurological deficits developed rapidly and did not progress after the initial 24 hours. MRI findings were most consistent with GBI. MRI, including pre‐ and post‐T1 weighted, T2 weighted, and fluid‐attenuated inversion recovery (FLAIR) studies, was used to image these animals. Abnormalities were seen post‐T1, T2, and FLAIR. Both animals improved neurologically with supportive care over several weeks, but both remained blind. New information: The use of MRI for diagnosing GBI.  相似文献   
993.
2001年北疆棉区低温冷害的发生特点及几点建议   总被引:12,自引:0,他引:12  
2001年7月28日至8月1日,在北疆棉区棉田发生了严重的低温冷害,减产达50%左右。对这场冷害的症状和发生特点及时进行了调查,就冷害发生程度与栽培措施的关系进行了分析,并对冷害发生后的救急措施及应用研究提出了建议。  相似文献   
994.
本文利用英吉沙国家一般气象站2001—2019年的基本气象资料及巴旦姆物候期观测资料和冻害调查资料,采用花芽受冻率及产量分析,结合相关气象要素的数理统计方法,对英吉沙巴旦姆越冬期间导致花芽冻害的气象因素进行分析。结果表明:在英吉沙,冬季最低气温及其持续日数、最低地表温度、冻土深度对巴旦姆花芽受冻造成影响较大,最大积雪深度及积雪持续日数的长短、冬季降水量的影响不太明显。其中当最低气温为-23℃~-18℃,其持续日数的长短、地表最低温度是导致英吉沙巴旦姆在越冬期间花芽受冻最严重的主要因素之一。  相似文献   
995.
本研究旨在探究唾液乳杆菌(Lactobacillus salivarius)对鸡毒支原体(Mycoplasma gallisepticum,MG)感染肉鸡生长性能及肺损伤的影响。选用1日龄AA肉鸡240只,按试验要求随机分为6组,包括对照组(Con)、低剂量唾液乳杆菌组(L)、高剂量唾液乳杆菌组(H)、MG感染组(MG)、MG感染+低剂量唾液乳杆菌组(MG+L)和MG感染+高剂量唾液乳杆菌组(MG+H)。Con组、MG组饲喂基础饲料,L组、MG+L组饲喂添加108 CFU·kg-1唾液乳杆菌的基础饲料,H组、MG+H组饲喂添加109 CFU·kg-1唾液乳杆菌的基础饲料,7日龄时给与MG组、MG+L组和MG+H组进行MG感染攻毒,饲养42 d后,通过分析各组鸡的体重、饲料转化率、肺部MG定植量、肺部病理损伤、肺部炎性损伤相关蛋白表达量及促炎性细胞因子含量来评价唾液乳杆菌缓解MG感染所致肉鸡生长性能下降及肺损伤效果。结果表明,MG感染极显著降低肉鸡体重(P<0.01),并极显著提高饲料转化率(P<0.01),而饲料中添加低剂量唾液乳杆菌和高剂量唾液乳杆菌均能极显著缓解MG感染所致肉鸡体重降低(P<0.01),并极显著改善饲料转化率(P<0.01)。饲料中添加低剂量唾液乳杆菌和高剂量唾液乳杆菌均能极显著降低MG肺部定植量(P<0.01);明显改善MG感染所致肺部病理损伤;极显著降低MG感染所致炎性损伤相关蛋白(TLR2、HMGB1、p-p65/p65、NLRP3、Pro-Caspase-1/Caspase-1)表达(P<0.01);极显著降低MG感染所致促炎性细胞因子(TNF-α、IL-1β、IL-6、IL-8)含量(P<0.01)。综上所述,饲料中添加唾液乳杆菌可以显著缓解MG感染所致肉鸡生长性能下降及肺损伤,该株唾液乳杆菌具有较大的应用潜力预防肉鸡感染MG。  相似文献   
996.
997.
AIM:To explore the effects of bone marrow-derived mesenchymal stem cells-conditioned medium (MSCs CdM) on lipopolysaccharide (LPS)-induced acute lung injury. METHODS:Lung injury was induced in mice by intraperitoneal injection of LPS. The mice were given a tail vein injection of MSCs CdM or normal saline 1 h after LPS administration. The mice were killed by an intraperitoneal injection of pentobarbital 6 h after LPS injection for either bronchoalveolar lavage fluid (BALF) and serum collection or lung histological analysis. RESULTS:Compared with control group, the BALF levels of protein, interleukin-10 (IL-10) and keratinocyte growth factor (KGF), the serum levels of tumor necrosis factor α (TNF-α) and IL-6, and the myeloperoxidase (MOP) activity in the lung tissues were significantly higher in LPS group, and severe pathological damages in the lung tissues were also observed. Treatment with MSCs CdM significantly reduced the BALF prtein level, the seum TNF-α and IL-6 levels and the lung MPO activity, and attenuated the lung pathological damages, but further increased the levels of IL-10 and KGF in the BALF. CONCLUSION:Treatment with MSCs CdM attenuates the lung injuries induced by LPS, which may be via regulating the expression of TNF-α, IL-6, IL-10 and KGF.  相似文献   
998.
The aim of this study was to evaluate the effects of MCC950 on growth performance, uric acid metabolism, serum inflammatory factor contents and kidney injury of goslings a fed high protein diet, and explore the potential mechanism of nucleotide binding oligomerization domain-like receptor 3 (NLRP3) / cysteine aspartase-1 (Caspase-1) signaling pathway in gosling gout. A total of 120 Yangzhou goslings of 1-day-old were randomly divided into 3 groups, which were control group, high protein group (HP group) and high protein+ MCC950 group (HP+MCC950 group), with 5 replicates in each group and 8 goslings in each replicate. The control group was fed a normal protein diet with 16.5% crude protein, and the HP group and HP+MCC950 group were fed a high protein diet with 24.0% crude protein. The HP+MCC950 group was intraperitoneally injected with MCC950 every 3 days at a dose of 10 mg / kg BW, and the other two groups were injected with the same amount of normal saline. The experiment lasted for 15 days. The results showed as follows: 1) compared with the control group, the average body weight of goslings at 15 days of age in the HP group was significantly decreased (P<0.05); the serum contents of uric acid (UA), creatinine (Cr), urea nitrogen (UN), C-reactive protein (CRP), interleukin-1β (IL-1β), interleukin 18 (IL-18), interleukin 6 (IL-6), tumor necrosis factor α (TNF-α) and transforming growth factor β1 (TGF-β1) in the HP group were significantly increased (P<0.05); the mRNA relative expression levels of NLRP3, Caspase-1, IL-1β and IL-18 and the protein relative expression levels of NLRP3, Caspase-1 and IL-1β in kidney tissues in the HP group were significantly increased (P<0.05). 2) Compared with the HP group, the average body weight of goslings at 10 and 15 days of age in the HP+MCC950 group was significantly increased (P<0.05); the serum contents of UA, Cr, UN, CRP, IL-1β, IL-18, IL-6, TNF-α and TGF-β1 were significantly decreased (P<0.05), while the mRNA relative expression levels of NLRP3, Caspase-1, IL-1β and IL-18 and the protein relative expression levels of NLRP3, Caspase-1 and IL-1β in kidney tissues in the HP+MCC950 group were significantly decreased (P< 0.05). 3) Histological findings showed that the renal tubules of goslings were dilated, and vacuolar degeneration and necrosis occurred in the HP group, while the structure of renal tubules was relatively normal in the HP+MCC950 group. The urate deposition area in kidney tissues of goslings in the HP group was significantly larger than that in the control group (P<0.05), and which in the HP+MCC950 group was significantly smaller than that in the HP group (P<0.05). Moreover, the urate deposition area in kidney tissues of goslings was significantly positively correlated with the protein relative expression level of NLRP3 (r = 0.681, P<0.05). In conclusion, MCC950 can promote the growth of goslings fed a high protein diet and reduce the serum uric acid content, which may be related to the reduction of inflammatory response and kidney injury through its inhibition of NLRP3 / Caspase-1 signaling pathway. © 2023 Authors. All rights reserved.  相似文献   
999.
Neuronal nitric oxide synthase (nNOS) has been implicated in peripheral nerve lesions and regeneration. The CAPON adaptor protein interacts with the PDZ domain of nNOS, helping to regulate nNOS activity at post-synaptic sites in neurones, but it is not known whether its expression is altered in sciatic nerves after chronic nerve constriction injury. In the present study, the spatiotemporal expression of CAPON was determined in chronically constricted rat sciatic nerves. Similar to the level of protein expression, CAPON mRNA was significantly up-regulated for almost 5 weeks following sciatic nerve injury. Immunohistochemistry demonstrated that increased CAPON was found mainly in S-100-positive Schwann cells. In addition, co-immunoprecipitation demonstrated an interaction between CAPON and nNOS in Schwann cells and the interaction was enhanced in injured sciatic nerves. CAPON may be involved in peripheral nerve regeneration through regulation of nNOS activity.  相似文献   
1000.
由于斑马鱼细胞组成、同源基因,免疫反应,药物代谢等方面与人类相比具有高度保守性。再加上斑马鱼体积小,产量大,适合被基因编辑等特点,适合于高通量的药物筛选。所以斑马鱼和斑马鱼胚胎常被用来模拟发育缺陷或化合物诱导的肝脏疾病。对斑马鱼作为肝脏疾病模型的优点,以及斑马鱼模型在免疫反应,药物代谢等方面的与人类的相似性进行综述。归纳了目前一些针对不同因素开发的斑马鱼模型及其相关病理机制以及相关药物筛选,并简要分析了其与哺乳动物模型的差异及优势,以期对肝脏疾病的药物筛选有所帮助。  相似文献   
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