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81.
Du YH Jia RY Yin ZQ Pu ZH Chen J Yang F Zhang YQ Lu Y 《Veterinary parasitology》2008,157(1-2):144-148
The acaricidal activity of the petroleum ether extract, the chloroform extract and the acetic ether extract of neem (Azadirachta indica) oil against Sarcoptes scabiei var. cuniculi larvae was tested in vitro. A complementary log-log (CLL) model was used to analyze the data of the toxicity tests. The results showed that at all test time points, the petroleum ether extract demonstrated the highest activity against the larvae of S. scabiei var. cuniculi, while the activities of the chloroform extract and the acetic ether extract were similar. The activities of both the petroleum ether extract and the chloroform extract against the larvae showed the relation of time and concentration dependent. The median lethal concentration (LC(50)) of the petroleum ether extract (1.3muL/mL) was about three times that of the chloroform extract (4.1muL/mL) at 24h post-treatment. At the concentrations of 500.0muL/mL, the median lethal time (LT(50)) of the petroleum ether extract and the chloroform extract was 8.4 and 9.6h, respectively. 相似文献
82.
家兔胸,腹,盆腔内脏初级传入神经元的分布特点 总被引:5,自引:0,他引:5
应用辣根过氧化物酶(HRP)法和荧光素逆行追踪法,对家兔心、肺、肝、胃、肾、子宫和膀胱的初级传入神经元分布规律进行了研究,结果表明,各内脏的初级传入神经元分布节段范围广泛,又有相对集中的节段;内脏与内脏之间的部分分布节段相互重叠,即使远距离相隔的内脏亦不例外,其中胸8 ̄10节段是胸、腹、盆腔脏器共同重叠节段;各内脏的感觉均经交感和副交感两个途径传入,其中心、肺、肝、肾、子宫以交感途径占优势,胃和膀 相似文献
83.
Shelan Liu Yong Yang Zhifeng Pang Ying Liu Huan Li Jian Cai Zhuoying Wu Yan Luo Yuhuan Tang Lihong Ying Shuwen Qin Ziping Miao Na Zhao Yijuan Chen Jinren Pan Shijian Li Zhao Yu Feng Ling Enfu Chen Zhiping Chen 《Zoonoses and public health》2023,70(1):93-102
A cluster of Chlamydia psittaci (C. psittaci) cases was reported in Zhejiang Province, China, 2019. This study evaluates the extent of the outbreak and determines the source of infection. Real-time PCR and sequencing of the ompA gene of C. psittaci were performed to identify the cases, the domesticated poultry and close contacts. The index patient was a 76-year-old woman with chronic vertigo, and Case 2 was a 64-year-old female farmer with herpes zoster. Both women bought psittaci-infected chickens or ducks from the same mobile street vendor and raised them for 10 days and 23 days before fever onset. There were no direct contact between the two women. C. psittaci test was positive for the two patients, one sick chicken, three healthy ducks and the vendor's chicken cage. Phylogenetic analysis showed that all seven C. psittaci positive samples carried identical ompA genotype A of C. psittaci. Of all of the patients' 148 close contacts, none tested positive for C. psittaci, or developed acute respiratory symptoms. Both patients were discharged after a 4-week hospital stay. In conclusion, the source of this cluster was the poultry infected with C. psittaci, which occasionally cause infections in farmers, but inter-human transmission seems unlikely. 相似文献
84.
Juzuo Zhang Liqun Xue Ang Nie Qing Yang Xuan Peng Zhilong Chen Lisha Yang Yang Xie Anwen Yuan Junfei Xu 《Reproduction in domestic animals》2020,55(11):1479-1489
Non-infectious prenatal mortality severely affects the porcine industry, with pathological placentation as a likely key reason. Previous studies have demonstrated that peroxisome proliferator-activated receptor gamma (PPARγ) deficiency causes defects in the uteroplacental vasculature and induces embryonic losses in mice. However, its role in porcine placental angiogenesis remains unclear. In the present study, PPARγ expression was investigated in porcine uteroplacental tissues at gestational day (GD) 25, GD40 and GD70 via quantitative polymerase chain reaction (qPCR), Western blot and immunohistochemistry (IHC). Moreover, the roles of PPARγ in porcine placental angiogenesis were investigated using a cell model of porcine umbilical vein endothelial cells (PUVECs) to conduct proliferation, migration and tube formation assays in vitro and a mouse xenograft model to assess capillary formation in vivo. The results showed that PPARγ was mainly located in the glandular epithelium, trophoblast, amniotic chorion epithelium and vascular endothelium, as indicated by the higher expression levels at GD25 and GD40 than at GD70 in endometrium and by higher expression levels at GD40 and GD70 than at GD25 in placenta. Moreover, PPARγ expression was significantly downregulated in placenta with dead foetus. In PUVECs, knocking out PPARγ significantly inhibited proliferation, migration and tube formation in vitro and inhibited capillary formation in mouse xenografts in vivo by blocking S-phase, promoting apoptosis and downregulating the angiogenic factors of VEGF and its receptors. Overall, the spatiotemporal heterogeneity of PPARγ expression in porcine uteroplacental tissue suggests its vital role in endometrial remodelling and placental angiogenesis, and PPARγ regulates placental angiogenesis through VEGF-mediated signalling. 相似文献
85.
Macroautophagy is a cellular degradation mechanism that involves the delivery of cytosolic components (macromolecules or organelles) by the autophagosome to the lysosome for degradation. In mammalian cells, macroautophagy and the ubiquitin proteasome system are 2 major mechanisms to eliminate abnormal proteins accumulated in pathological conditions. Here, the coordination of the 2 pathways to alleviate endoplasmic reticulum stress is reviewed. Also discussed is the regulatory role of macroautophagy and proteasome activity in cell survival and death, as well as the recent discoveries leading to novel strategies of simultaneous control of the proteasome and autophagy activity in anticancer treatment. 相似文献
86.
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89.
Nan‐Xi Hu Mei Chen Yi‐Song Liu Qi Shi Bo Yang Huan‐Cheng Zhang Pi Cheng Qi Tang Zhao‐Ying Liu Jian‐Guo Zeng 《Journal of veterinary pharmacology and therapeutics》2019,42(2):197-206
Sanguinarine (SA) and chelerythrine (CHE) are the main active components of the phytogenic livestock feed additive, Sangrovit®. However, little information is available on the pharmacokinetics of Sangrovit® in poultry. The goal of this work was to study the pharmacokinetics of SA, CHE, and their metabolites, dihydrosanguinarine (DHSA) and dihydrochelerythrine (DHCHE), in 10 healthy female broiler chickens following oral (p.o.) administration of Sangrovit® and intravenous (i.v.) administration of a mixture of SA and CHE. The plasma samples were processed using two different simple protein precipitation methods because the parent drugs and metabolites are stable under different pH conditions. The absorption and metabolism of SA following p.o. administration were fast, with half‐life (t1/2) values of 1.05 ± 0.18 hr and 0.83 ± 0.10 hr for SA and DHSA, respectively. The maximum concentration (Cmax) of DHSA (2.49 ± 1.4 μg/L) was higher that of SA (1.89 ± 0.8 μg/L). The area under the concentration vs. time curve (AUC) values for SA and DHSA were 9.92 ± 5.4 and 6.08 ± 3.49 ng/ml hr, respectively. Following i.v. administration, the clearance (CL) of SA was 6.79 ± 0.63 (L·h?1·kg?1) with a t1/2 of 0.34 ± 0.13 hr. The AUC values for DHSA and DHCHE were 7.48 ± 1.05 and 0.52 ± 0.09 (ng/ml hr), respectively. These data suggested that Sangrovit® had low absorption and bioavailability in broiler chickens. The work reported here provides useful information on the pharmacokinetic behavior of Sangrovit® after p.o. and i.v. administration in broiler chickens, which is important for the evaluation of its use in poultry. 相似文献
90.
桑椹红色素稳定性的研究 总被引:13,自引:2,他引:13
研究了光和热等物理因素、常用食品添加剂、金属离子、氧化剂及还原剂对桑椹红色素稳定性的影响。结果表明 :pH值对桑椹色素的影响显著 ,在酸性条件下色素稳定 ;长时间高温和光照对色素有明显的破坏作用 ;金属离子Na+ 、Ca2 + 、Cu2 + 、Fe2 + 、Mg2 + 、Zn2 + 和Mn2 + 对桑椹色素色泽有一定的增色效果 ,但Fe3 + 则有明显的不良影响 ;食品中常用的葡萄糖、蔗糖、苯甲酸钠和山梨酸钾对桑椹色素无明显的不良影响 ;VC对桑椹色素有双重作用 ,而H2 O2 和Na2 SO3 对色素有严重的破坏作用。 相似文献