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排序方式: 共有7147条查询结果,搜索用时 15 毫秒
1.
目的:探讨脑出血对酵母沉默信息调节因子2(Sirt2)和炎症的影响。方法:将胶原酶Ⅳ注入SD大鼠右侧
纹状体中建立脑出血模型,通过免疫印迹和ELISA 等方法测定大鼠脑出血后48 h 的Sirt2 的表达及炎症变化。利
用Hemin 诱导PC12 细胞损伤模拟体外脑出血模型,并检测Sirt2 及炎症变化;采用短发夹RNA(shRNA)-Sirt2 沉
默Sirt2 在PC12 细胞中的表达及对炎症的影响。结果:手术后48 h 脑出血行为学评分最低。脑出血组Sirt2 的表达
显著高于假手术组。脑出血组IL-6、IL-1β 表达显著升高。结论:脑出血可以促进Sirt2 的表达和炎症反应,降低
Sirt2 的表达可减缓炎症反应。
关键词 脑出血;沉默信息调节 相似文献
2.
目的:采用高效液相色谱-三重四级杆质谱(HPLC-MS/MS)测定清血八味片中的化学成分。方法:在负离子条件下采用Halo C_(18)色谱柱(2.1 mm×100 mm,2.7μm),以0.1%甲酸-10 mmol/L甲酸铵水和乙腈为流动相进行梯度洗脱,质谱采用Scan模式和MRM模式,检测清血八味片中的化学成分。结果:共鉴定出紫草中成分7种、土木香中成分3种、人工牛黄中成分4种、栀子中成分7种、瞿麦中成分7种、甘草中成分12种。结论:该方法快速可靠,操作简便,可用于清血八味片的质量控制研究,为临床药物使用提供一定的依据。 相似文献
3.
Deoxynivalenol (DON) has broad toxicity in animals and humans. In this study the impact of DON treatment on apoptotic pathways in PC12 cells was determined. The effects of DON were evaluated on (i) typical indicators of apoptosis, including cellular morphology, cell activity, lactate dehydrogenase (LDH) release, and apoptosis ratio in PC12 cells, and on (ii) the expression of key genes and proteins related to apoptosis, including Bcl-2, Bax, Bid, cytochrome C (Cyt C), apoptosis inducing factor (AIF), cleaved-Caspase9, and cleaved-Caspase3. DON treatment inhibited proliferation of PC12 cells, induced significant morphological changes and apoptosis, promoted the release of Cyt C and AIF from the mitochondria, and increased the activities of cleaved-Caspase9 and cleaved-Caspase3. Bcl-2 expression decreased with increasing DON concentrations, in contrast to Bax and Bid, which were increased with increasing DON concentration. These data demonstrate that DON induces apoptosis in PC12 cells through the mitochondrial apoptosis pathway. 相似文献
4.
Animal behaviour can be viewed as a stream of elements, which, once accurately described, can be counted and timed. Data acquisition techniques and tools are reviewed, and some strategies for collection and analysis of data using PC computers are suggested. Automated instruments are not satisfactory for the study of complex behaviour and as such systemic observation remains irreplaceable. IBM PC-type computers, with a wide range of analytical software (e.g., spreadsheets, statistical packages, technical graphics), are practical for data acquisition. Several systems which can satisfy different applications are reviewed. Some systems can communicate with a videorecorder, a facility which remarkably increases the accuracy of measurement; this is essential for meaningful analyses of the internal structure of behavioural streams (sequences, time patterns) or communication processes. The power of new tools enables behavioural measurement with the necessary complexity to allow a whole new set of questions to be addressed. However, it also increases demands for meaningful content and analysis of data. 相似文献
5.
6.
Eileen J. Martin Kiran S. Panickar Michael A. King Malgorzata Deyrup Bruce E. Hunter Geehuan Wang Edwin M. Meyer 《Drug development research》1994,31(2):135-141
The potential cytoprotective actions of a novel nicotinic agent 2,4-dimethoxybenzilidene anabaseine (DMXB) were investigated in differentiated PC12 cells and transected rat septal cholinergic neurons in vivo. In NGF-differentiated PC12 cells, removal of both NGF and serum led to cell loss, a reduced % of cells expressing neurites, the release of lactate dehydrogenase, and a decrease in total cellular protein. Cell loss was apparent within 24 h, and remained constant between 4–8 days post-NGF removal. NGF alone (100 ng/ml), DMXB (10 μM), but not nicotine (10 μM), prevented these cell and neurite losses. DMXB-induced cytoprotection was blocked by 1 μM mecamylamine. DMXB (1 mg/kg, ip) injected twice but not once per day protected cholinesterase-staining septal neurons from retrograde degeneration following unilateral fimbrial transections. The twice per day DMXB injection-protocol also decreased cell roundness among cholinesterase-staining cells in the lesioned septal hemisphere compared to saline-injected animals. These studies suggest that DMXB may exert cytoprotective activity in NGF-sensitive neuronal populations. © 1994 Wiley-Liss, Inc. 相似文献
7.
Summary: To develop a method for identification of differential gene expression between different cell populations, several convenient techniques of molecular biology, including subtractive hybridization, suppression PCR, T/A cloning and sequencing, were used to identify genes expressed differentially in CD45^- and CD45^- cells isolated from U266 cell line of multiple myeloma. Our results showed that the levels of abundant genes scale down 20 times through subtractive hybridization.Plasmid DNA from CD45^- cell clones was hybridized with forward or backward cDNA probes synthesized from CD45^- and CD45 cells, respectively. A few of differentially expressed genes reconfirmed by RT-PCR were identified from 500 expressed clones of CD45^- cells. It is concluded that a strategy for gene expression identification developed from conventional molecular biological methods can be used in different laboratories. 相似文献
8.
9.
鼻内镜鼻窦手术后应用香菊片对粘膜转归的影响 总被引:4,自引:0,他引:4
目的 观察内镜鼻窦手术后应用香菊片对术腔粘膜转归的影陶。方法 Ⅱ型鼻窦炎、鼻息肉患者180例作为治疗组,行内镜鼻窦手术后,在常规辅助治疗基础上加用香菊片口服,并设ll0例Ⅱ型鼻窦炎、鼻息肉患者作为对照组,对比观察术腔清洁时间、术腔上皮化时间及术后复发率。结果 治疗组术腔清洁时间平均为:Ⅰ期1.5周,Ⅱ期1.8周,Ⅲ期2.1周;对照组Ⅰ期2.0周,Ⅱ期2.5周,Ⅲ期3.3周,差异有显著性意义(P<0.01)。治疗组术腔上皮化时间平均为:Ⅰ期7.0周,Ⅱ期7.5周,Ⅲ期7.8周;对照组Ⅰ期8.0周,Ⅱ期8.4周,Ⅲ期9.0周,差异有显著性意义(P<0.01)。治疗组术后复发率为4.4%,明显少于对照组7.3%。结论 内镜鼻窦手术后,应用香菊片对鼻腔功能的恢复具有良好的疗效,并能减少复发率,可做为常规药物应用临床。 相似文献
10.
A Botulinum neurotoxin serotype A (BoNT/A) ELISA detection system was developed based upon an 11-mer cyclic peptide, termed C11-019, that was identified through peptide phage display technology. The assay employs a sandwich format using the C11-019 cyclic peptide attached to a PEMA (poly(ethylene maleic anhydride)) matrix as the capture phase and anti-BoNT/A polyclonal antibodies as the detection phase. Results reported demonstrate that the C11-019 peptide–polymer can specifically bind to BoNT/A with no cross-reactivity to other serotypes examined in assay buffers and a variety of body fluids and foodstuffs. When a highly sensitive chemiluminescent substrate was engaged, the detection of 1 pg/mL could be readily achieved within 3 h with a linear range of 0.1–1 ng/mL. These results demonstrate that an inexpensive peptide–polymer-based capture ELISA system can be used for rapid, sensitive and highly specific BoNT detection. 相似文献