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1.
EGF对急性胰腺炎大鼠肠道细胞凋亡的影响 总被引:1,自引:0,他引:1
目的:探讨表皮生长因子(EGF)对急性胰腺炎(AP)大鼠肠道细胞凋亡影响的机理。方法:72只雄性SD大鼠AP模型随机分为3组:对照组(仅开腹翻动胰腺,n=24)、AP组(n=24)及APEGF组(n=24)。APEGF组皮下注射EGF0.1μg·g-1,其余两组动物皮下注射相同体积的生理盐水。每次8只大鼠分别于术后6h、12h、24h剖杀取材,经心脏取血2ml,采用全自动生化分析仪检测血清淀粉酶,以干纱布吸沾腹水法测量腹水量。从屈氏韧带远侧10cm处开始取2cm空肠,观测空肠组织细胞凋亡;另取10cm空肠,检测空肠粘膜MDA(丙二醛)含量。结果:术后12h及24h,APEGF组动物腹水量显著低于AP组(P<0.05,P<0.01),APEGF组动物血清淀粉酶也显著低于AP组(P<0.05,P<0.01);术后24h,APEGF组动物血浆、空肠组织MDA含量均显著低于AP组;术后12h及24h,空肠粘膜凋亡指数显著低于AP组。结论:EGF能迅速恢复血清淀粉酶正常活性,降低AP大鼠血浆、肠粘膜组织MDA含量,减轻AP所致的肠粘膜细胞凋亡损害。 相似文献
2.
为了考察海藻酸钙/聚组氨酸微胶囊的毒性特征,我们利用MTT比色法和小鼠尾静脉注射法,分别考察了该微胶囊的细胞毒性和急性全身毒性。结果表明:微胶囊浓度≤1.0mg/mL时,材料对L929细胞生长无明显抑制作用;微胶囊浸提液即使在高浸提比(10.0mg/mL)下,浸提产物也无细胞毒性作用。急性全身毒性试验结果显示:微胶囊浸提液不引起急性全身毒性反应,表明微胶囊浸提液无有毒的沥滤物和降解产物产生。说明海藻酸钙/聚组氨酸微胶囊无明显毒性。 相似文献
3.
Germinal center and activated b-cell profiles separate Burkitt lymphoma and diffuse large B-cell lymphoma in AIDS and non-AIDS cases 总被引:1,自引:0,他引:1
Gormley RP Madan R Dulau AE Xu D Tamas EF Bhattacharyya PK LeValley A Xue X Kumar P Sparano J Ramesh KH Pulijaal V Cannizzaro L Walsh D Ioachim HL Ratech H 《American journal of clinical pathology》2005,124(5):790-798
Morphologic features of Burkitt lymphoma (BL) and diffuse large B-cell lymphoma (DLBCL) overlap. No single phenotypic marker or molecular abnormality is pathognomonic. We tested a panel of 8 germinal center (GC) and activated B-cell (ABC) markers for their ability to separate BL and DLBCL. We diagnosed 16 BL and 39 DLBCL cases from 21 patients with AIDS and 34 without AIDS based on traditional morphologic criteria, Ki-67 proliferative index, and c-myc rearrangement (fluorescence in situ hybridization). After immunohistochemically staining tissue microarrays of BL and DLBCL for markers of GC (bcl-6, CD10, cyclin H) and ABC (MUM1, CD138, PAK1, CD44, bcl-2), we scored each case for the percentage of positive cells. Hierarchical clustering yielded 2 major clusters significantly associated with morphologic diagnosis (P < .001). For comparison, we plotted the sum of the GC scores and ABC scores for each case as x and y data points. This revealed a high-GC/low-ABC group and a low-GC/high-ABC group that were associated significantly with morphologic diagnosis (P < .001). Protein expression of multiple GC and ABC markers can separate BL and DLBCL. 相似文献
4.
Meiling Zhang Jienan Zhou Senquan Jia Xiaonan Zhao Yaoyao Chen Yanhong Sun Zhaosheng Liu Xiaofang Zhou Duo Li Chunrui Luo Yong Zhang Violet Magoma Onsongo Yong Shao Xiaoqing Fu 《Emerging infectious diseases》2021,27(5):1543
To limit the spread of severe acute respiratory syndrome coronavirus 2, the government of China has been monitoring infected travelers and minimizing cold-chain contamination. However, other factors might contribute to recurring outbreaks. We analyze the role of undocumented migrants as potential transmitters of severe acute respiratory syndrome coronavirus 2 in China. 相似文献
5.
Jing Sun Xianyang Chen Yongru Wang Yuelin Song Bo Pan Bei Fan Fengzhong Wang Xiaonan Chen Pengfei Tu Jiarui Han Huixia Huo Jun Li 《中草药(英文版)》2023,15(3):430-438
Objective: The present study aimed to evaluate the therapeutic effect and explore the underlying mechanisms of Longxue Tongluo Capsule (LTC) on ischemic stroke rats.
Methods: Twenty-six rats were randomly divided into four groups, including sham group, sham + LTC group, MCAO group, and MCAO + LTC group. Ischemic stroke rats were simulated by middle cerebral artery occlusion (MCAO), and LTC treatment group were orally administrated with 300 mg/kg of LTC once daily for seven consecutive days. LTC therapy was validated in terms of neurobehavioral abnormality evaluation, cerebral infarct area, and histological assessments. The plasma metabolome comparisons amongst different groups were conducted by UHPLC-Q Exactive MS in combination with subsequent multivariate statistical analysis, aiming to finding the molecules in respond to the surgery or LTC treatment.
Results: Intragastric administration of LTC significantly decreased not only the neurobehavioral abnormality scores but also the cerebral infarct area of MCAO rats. The interstitial edema, atrophy, and pyknosis of glial and neuronal cells occurred in the infarcted area, core area, and marginal area of cerebral cortex were improved after LTC treatment. A total of 13 potential biomarkers were observed, and Youden index of 11 biomarkers such as LysoPC, SM, and PE were more than 0.7, which were involved in neuroprotective process. The correlation and pathway analysis showed that LTC was beneficial to ischemic stroke rats via regulating glycerophospholipid and sphingolipid metabolism, together with nicotinate and nicotinamide metabolism. Heatmap and ternary analysis indicated the synergistic effect of carbohydrates and lipids may be induced by flavonoid intake from LTC.
Conclusion: The present study could provide evidence that metabolomics, as systematic approach, revealed its capacity to evaluate the holistic efficacy of TCM, and investigate the molecular mechanism underlying the clinical treatment of LTC on ischemic stroke. 相似文献
6.
目的分析烟台市5起伤寒病原学特征及分子流行病学关联。方法2018年自烟台市5例伤寒确诊病例样本和流行病调查样本分离获得6株伤寒沙门菌菌株,病例发病时间自2018年5月26日至7月24日,分别分布于烟台牟平区水道镇、烟台蓬莱区登州街道、烟台龙口东莱街道、烟台牟平区文化街道、烟台芝罘区福莱山街道。采用常规细菌分离方法和XbaⅠ/BlnⅠ双酶切脉冲场凝胶电泳(PFGE)技术对伤寒杆菌进行溯源分析,同时开展viaB毒力基因检测和27种临床常用抗生素敏感试验对伤寒杆菌进行病原学研究。结果6株伤寒杆菌经PFGE-XbaⅠ和PFGE-BlnⅠ电泳分为4个PFGE模式,其中3株菌同源性100%;1株多耐药菌(外籍患者),1株单耐药菌(外省滞留史患者),1株完全敏感菌,同一PFGE模式的3株菌药敏表型一致,除对氨基糖甙类和喹诺酮类部分抗生素中介外,对其他抗生素均敏感;除外籍患者标本分离株viaB基因阴性外,其他菌viaB基因均阳性。结论烟台寒杆菌对临床常用抗生素敏感性良好,仍需重视伤寒散发病例发生和伤寒输入感染。 相似文献
7.
中西医结合治疗血管性痴呆症36例观察 总被引:1,自引:0,他引:1
目的:观察中西医结合治疗血管性痴呆(VD)的疗效。方法:治疗组36倒,用中西医结合治疗,对照组33倒用喜得镇加脑复康治疗,观察治疗3个月。观察治疗前后患者的中医症状变化,以及简易智力状态量表(MMSE)和日常生活能力量表(ADL)积分的改变。结果:治疗组中医症状积分、ADL积分降低,MMES积分增加。本组治疗前后比较有极显著差异(P〈0.01),治疗组与对照组比较也有显著性差异(P〈0.05)。结论:中西医结合治疗血管性痴呆(VD),能够促进学习记忆的恢复,改善临床症状,是治疗VD的有效方法。 相似文献
8.
疑诊肺部真菌感染的10例经验性用药分析 总被引:1,自引:1,他引:0
目的 探讨疑诊肺部真菌感染的经验性抗真菌用药方案.方法 对疑诊肺部真菌感染并以经验性广谱抗真菌治疗好转10例患者的临床资料进行回顾分析.结果 10例患者主要临床表现为发热(10/10)、咳嗽、咳痰(8/10).胸部CT检查均表现为密度较高的感染性病灶(5例伴空洞,8例伴光晕征).4例痰培养见真菌孢子和菌丝.8例有真菌感染危险因素,3例初用氟康唑治疗无效,改用伊曲康唑好转;6例用伊曲康唑好转;1例用两性霉素B好转.结论 肺部真菌感染确诊困难,流行病学调查显示非白念真菌发病率有增高趋势,疑诊肺部真菌感染应及时将广谱抗真菌治疗作为一线药物. 相似文献
9.
Enshuai Wang Fei Yang Xinmin Shen Haiqin Duan Xiaonan Zhang Qin Yin Wenqiang Peng Xiaocui Yang Liu Yang 《Materials》2022,15(10)
An acoustic metamaterial absorber of parallel–connection square Helmholtz resonators is proposed in this study, and its sound absorption coefficients are optimized to reduce the noise for the given conditions in the factory. A two–dimensional equivalent simulation model is built to obtain the initial value of parameters and a three–dimensional finite element model is constructed to simulate the sound absorption performance of the metamaterial cell, which aims to improve the research efficiency. The optimal parameters of metamaterial cells are obtained through the particle swarm optimization algorithm, and its effectiveness and accuracy are validated through preparing the experimental sample using 3D printing and measuring the sound absorption coefficient by the standing wave tube detection. The consistency between the experimental data and simulation data verifies feasibility of the proposed optimization method and usefulness of the developed acoustic metamaterial absorber, and the desired sound absorption performances for given conditions are achieved. The experimental results prove that parallel–connection square Helmholtz resonators can achieve an adjustable frequency spectrum for the low frequency noise control by parameter optimization, which is propitious to promote its application in reducing the noise in the factory. 相似文献
10.
Peihua Liu Ling Jiang Weimin Kong Qiushi Xie Ping Li Xiaonan Liu Jiayi Zhang Ming Liu Zhongjian Wang Liang Zhu Hanyu Yang Ying Zhou Jianjun Zou Xiaodong Liu Li Liu 《药学学报(英文版)》2022,12(5):2391
Drug-induced hyperglycemia/diabetes is a global issue. Some drugs induce hyperglycemia by activating the pregnane X receptor (PXR), but the mechanism is unclear. Here, we report that PXR activation induces hyperglycemia by impairing hepatic glucose metabolism due to inhibition of the hepatocyte nuclear factor 4-alpha (HNF4α)‒glucose transporter 2 (GLUT2) pathway. The PXR agonists atorvastatin and rifampicin significantly downregulated GLUT2 and HNF4α expression, and impaired glucose uptake and utilization in HepG2 cells. Overexpression of PXR downregulated GLUT2 and HNF4α expression, while silencing PXR upregulated HNF4α and GLUT2 expression. Silencing HNF4α decreased GLUT2 expression, while overexpressing HNF4α increased GLUT2 expression and glucose uptake. Silencing PXR or overexpressing HNF4α reversed the atorvastatin-induced decrease in GLUT2 expression and glucose uptake. In human primary hepatocytes, atorvastatin downregulated GLUT2 and HNF4α mRNA expression, which could be attenuated by silencing PXR. Silencing HNF4α downregulated GLUT2 mRNA expression. These findings were reproduced with mouse primary hepatocytes. Hnf4α plasmid increased Slc2a2 promoter activity. Hnf4α silencing or pregnenolone-16α-carbonitrile (PCN) suppressed the Slc2a2 promoter activity by decreasing HNF4α recruitment to the Slc2a2 promoter. Liver-specific Hnf4α deletion and PCN impaired glucose tolerance and hepatic glucose uptake, and decreased the expression of hepatic HNF4α and GLUT2. In conclusion, PXR activation impaired hepatic glucose metabolism partly by inhibiting the HNF4α‒GLUT2 pathway. These results highlight the molecular mechanisms by which PXR activators induce hyperglycemia/diabetes.Key words: Pregnane X receptor, Hepatocyte nuclear factor 4-alpha, Glucose transporter 2, Hepatic glucose uptake, Diabetes, Drug-induced hyperglycemia 相似文献