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1.
The potential antidepressant effect of flerobuterol (dl-(fluoro-2 phenyl)-1 t-butylamino-2 ethanol), a new drug related to beta-adrenoceptor agonists, was evaluated and compared with imipramine and salbutamol using classical psychopharmacological tests in mice. Like imipramine and salbutamol, flerobuterol (0.5-32 mg kg-1, ip) fully prevented apomorphine (16 mg kg-1, sc)- and partly reversed reserpine- and oxotremorine-induced hypothermia. At higher doses (16-32 mg kg-1), flerobuterol enhanced the toxic effects of yohimbine. Unlike imipramine, flerobuterol and salbutamol did not reduce immobility duration in the behavioural despair test. Salbutamol and flerobuterol decreased locomotor activity. Flerobuterol did not induce mydriasis, did not prevent oxotremorine-induced tremors or salivary and lacrimal gland secretion and did not reduce reserpine-induced palpebral ptosis. Propranolol (8 mg kg-1, ip) but not alpha-methyl-paratyrosine (75 mg kg-1, ip) prevented the flerobuterol-induced antagonism of apomorphine-induced hypothermia. Our results suggest that flerobuterol demonstrates potential antidepressant activity, which could be related to beta-adrenoceptor activation in mice.  相似文献   
2.
目的探究环状RNALrp6(circLrp6)对过氧化氢(H2O2)诱导的H9c2心肌细胞凋亡的影响。方法通过Sanger测序和RNaseR酶切验证circLrp6的环状结构;细胞荧光原位杂交分析circLrp6的亚细胞定位;通过RT-qPCR检测H2O2处理的H9c2细胞和缺血再灌注损伤的小鼠心脏组织中circLrp6的差异表达水平;采用TUNEL染色检测circLrp6是否影响H2O2诱导的心肌细胞凋亡水平;通过生物信息学的方法预测与circLrp6相互结合的下游靶点及其结合位点。结果circLrp6具有环状结构,定位于细胞核,它在H2O2处理后的H9c2心肌细胞和缺血再灌注的心脏组织中表达水平下调(P<0.05),过表达circLrp6对H2O2处理的心肌细胞具有保护作用,表现为TUNEL染色阳性率下降(P<0.05)。另外,circLrp6具有结合miRNA和蛋白质的潜能。结论circLrp6对H2O2诱导的心肌细胞凋亡具有抑制作用。  相似文献   
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Enteric pathogens associated with diarrhea were studied for two years at a diarrhea treatment center in rural Bangladesh. Enterotoxigenic Escherichia coli (ETEC) was the most frequently identified pathogen for patients of all ages. Rotavirus and ETEC were isolated from approximately 50% and approximately 25%, respectively, of patients less than two years of age. A bacterial or viral pathogen was identified for 70% of these young children and for 56% of all patients with diarrhea. Most ETEC isolates were obtained in the hot dry months of March and April and the hot wet months of August and September. Rotavirus identification peaked in the cool dry months of December and January, but infected patients were found year-round. The low case-fatality rates for patients with watery diarrhea and substantial dehydration further document the usefulness of treating patients with diarrhea with either a glucose- or sucrose-base electrolyte solution such as those used in this treatment center.  相似文献   
6.
32例国产人工髋关节翻修手术的临床体会   总被引:5,自引:3,他引:5  
目的:探讨国产人工髋关节翻修原因。方法:回顾总结32例人工髋关节翻修中发现的问题,分析翻修原因。结果:32例中术前诊断松动16例,脱位4例,深部感染2例,白磨通3例,断柄2例,髋周及股部疼痛4例,股骨柄穿通皮质1例。26例取出假体顺利,6部部分骨长入珍珠面而取出假体困难。25例作全髋置换翻修,4例臼怀松动或位置不良致脱位仅翻修髋臼,1例股骨柄穿通皮质更换双动头,2例因深部感染严重而作单纯假体取出、清创术。全组病例经6个月-5年随访,Harris评分术前平均43分,术后平均81分,平均增加38分。结论:目前翻修病例仍以国产人工关节为主。翻修原因主要是:人工关节质量因素和手术技术因素。造成假体过早松动或种种其它并发症,最终失败。提示国产人工关节质量需改进,需相应配套器械,手术操作技术有待提高。  相似文献   
7.
Targeted gene disruption of murine CD7   总被引:2,自引:0,他引:2  
CD7 is a 40 kDa type I transmembrane glycoprotein member of the Ig superfamily. CD7 is a marker of mature human T cells and NK cells, and is expressed early in their development. Cross-linking CD7 positively modulates T cell and NK cell activity as measured by calcium fluxes, expression of adhesion molecules, cytokine secretion and proliferation. CD7 associates directly with phosphoinositol 3'-kinase, and CD7 ligation induces production of D-3 phosphoinositides and tyrosine phosphorylation. Severe combined immunodeficiency has been associated with a lack of lymphocyte surface CD7. The CD7 ligand is unknown. The murine CD7 homolog is encoded by a single gene on chromosome 11. In order to characterize the role of CD7 in lymphocyte development and function we have eliminated the CD7 gene by targeted disruption. CD7- deficient mice display normal histology of thymus and spleen, normal lymphocyte populations in primary and secondary lymphoid tissues, and normal serum Ig levels. Specific antibody responses after immunization with T-dependent and T-independent antigens are equivalent in wild-type and CD7 knockout mice. CD7-deficient lymphocytes respond normally to T cell mitogenic and allogeneic stimuli, and display normal NK cell cytotoxicity.   相似文献   
8.

Background

The increased reports of ESBL dissemination from various centres in south western, Nigeria and the recent emergence of carbapenem resistant bacteria prompted the conception of this study.

Objectives

To demonstrate the relationship between high molecular weight plasmids and the expression of antibiotic multi-resistance including ESBL and carbapenemase.

Methods

We investigated 97 isolates of selected organisms consisting of 67 E. coli and 30 Klebseilla spp for the presence of plasmids expressing ESBL including carbapenem-hydrolysing enzymes. Beta-lactamase was determined using acidometric method, while ESBL and carbapenemase activity was determined using the double-disk diffusion test as well as the Modified Hodge test (MHT). Plasmid profiles of ESBL and carbapenemase positive isolates were determined according to standard protocols.

Results

An ESBL prevalence rate of 21.6% and carbapenem- resistance rate of 9.3% was recorded. Antibiotic susceptibility profile of ESBL isolates showed 100.0% resistance against Amoxicillin, Cotrimoxazole and Erythromycin. Moderate susceptibility was recorded against the Quinolone class of antibiotics; Meropenem remained the most active antibiotic against ESBL isolates with 62.5% against E. coli and 60% against K. pneumoniae. The plasmid profiles of our study isolates ranged from 11.8kbp to 35.5kbp.

Conclusion

Due to the relationship between high molecular weight plasmids and multi-drug resistance, we hereby recommend regular molecular surveillance of this form in our study setting.  相似文献   
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Myelinated and nonmyelinated nerves: comparison of proton MR properties   总被引:1,自引:0,他引:1  
Jolesz  FA; Polak  JF; Adams  DF; Ruenzel  PW 《Radiology》1987,164(1):89-91
The magnetic resonance (MR) relaxation rates of protons were compared in the myelinated and nonmyelinated nerves of the garfish. The long, large olfactory nerve of the garfish, as an easily accessible source of nonmyelinated axons, is uniquely suited for such a comparison. The T1 and T2 measurements revealed distinct and consistent differences between nonmyelinated olfactory nerves and myelinated optic and oculomotor nerves. Comparisons between water content, lipid content, and relaxation rates indicated that the differences in MR properties represent complex differences in the distribution and physical environment of the constituent lipid and water protons.  相似文献   
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