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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   
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3.
Background: The cardiotoxic mechanism of local anesthetics may include interruption of cardiac sympathetic reflexes. The authors undertook this investigation to determine if clinically relevant concentrations of bupivacaine and levobupivacaine interfere with exocytotic norepinephrine release from cardiac sympathetic nerve endings.

Methods: Rat atria were prepared for measurements of twitch contractile force and 3[H]-norepinephrine release. After nerve endings were loaded with 3[H]-norepinephrine, the tissue was electrically stimulated in 5-min episodes during 10 10-min sampling periods. After each period, a sample of bath fluid was analyzed for radioactivity and 3[H]-norepinephrine release was expressed as a fraction of tissue counts. Atria were exposed to buffer alone during sampling periods 1 and 2 (S1 and S2). Control atria received saline (100 [mu]l each, n = 6 atria) in S3-S10. Experimental groups (n = 6 per group) received either bupivacaine or levobupivacaine at concentrations (in [mu]M) of 5 (S3-S4), 10 (S5-S6), 30 (S7-S8), and 100 (S9-S10).

Results: Bupivacaine and levobupivacaine decreased stimulation-evoked fractional 3[H]-norepinephrine release with inhibitory concentration 50% values of 5.1 +/- 0.5 and 6.1 +/- 1.3 [mu]m. The inhibitory effect of both local anesthetics (~70%) approached that of tetrodotoxin. Local anesthetics abolished the twitch contractions of atria with inhibitory concentration 50% values of 12.6 +/- 5.0 [mu]m (bupivacaine) and 15.7 +/- 3.9 [mu]m (levobupivacaine). In separate experiments, tetrodotoxin inhibited twitch contractile force by only 30%.  相似文献   

4.
目的:研究安氏I类错(牙合)患者中,分别采用微型种植体作支抗与口内前牙作支抗近移下颌磨牙进行比较,以评价两种方法的各自特点。方法:将24例成人患者随机分成两组,分别采用两种方法近移下颌磨牙。测量下颌第二磨牙在移动速度和近远中方向、垂直方向的位置变化,以衡量磨牙的位置改变,并通过下颌中切牙的位置变化,评价支抗强弱。结果:种植体作支抗组下颌第二磨牙平均近中移动8.5mm,疗程10.4个月,平均移动速度0.82mm/月,磨牙长轴向近中倾斜2.5°,磨牙垂直向压低0.28mm,下颌中切牙位置无改变。对照组下颌第二磨牙平均近中移动7.8mm,疗程10.2个月,平均移动速度0.76mm/月,磨牙长轴向近中倾斜角度7.5°,磨牙垂直向压低0.06mm,下颌中切牙发生舌向倾斜9.5°。下颌中切牙切端向舌侧移动了3.0mm。结论:两种方法比较,种植体的支抗更强,未见前牙支抗丧失。二者磨牙的移动方式有所区别。  相似文献   
5.
The ileoanal J pouch: radiographic evaluation   总被引:1,自引:0,他引:1  
Hillard  AE; Mann  FA; Becker  JM; Nelson  JA 《Radiology》1985,155(3):591-594
Endorectal ileoanal pull-through offers an attractive alternative to proctocolectomy and ileostomy for patients with ulcerative colitis, Gardner syndrome, and familial polyposis. To our knowledge, a careful radiographic analysis of the ileum, ileal pouch, and ileoanal anastomosis after ileoanal pull-through has not been reported. Thirty-two patients with ulcerative colitis, Gardner syndrome, and familial polyposis underwent colectomy, mucosal proctectomy, and endorectal ileoanal pull-through of a 15-cm ileal "J" pouch and loop ileostomy. Twenty-five (78%) of 32 of all the pouches radiographically demonstrated spiral folds extending from the middle of the pouch to the pectinate line. Other radiographic features included a mesenteric mass effect, pseudopolyps, and a central lucency that indicated intrapouch sutures. Radiographs provide useful information in the postoperative management of the ileal pull-through.  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.
BACKGROUND: Asthma mortality rates have been increasing despite our improved understanding of the pathophysiology of asthma and advanced methods of treatment. Although there are many national studies of asthma mortality rates, few studies have concentrated on subnational regions such as individual states. OBJECTIVES: We sought to determine the trends in asthma mortality in children and young adults during the last 15 years in Louisiana. METHODS: Asthma mortality data were acquired from the Louisiana State Center for Health Statistics for the years 1983 through 1997. All asthma deaths coded International Classification of Disease, Ninth Revision 493 were included in the data set along with year, sex, and rate characteristics. State population estimates obtained from the United States Bureau of Census for three 5-year periods (1983 to 1987, 1988 to 1992, and 1993 to 1997) were used to calculate crude and adjusted mortality rates. These time periods were compared with one another and with the period 1983 to 1987, which was used as a baseline. RESULTS: For all residents, the mortality rate increased from 0.41 deaths per 100,000 persons during the 1983 to 1987 time period to 0.49 and 0.63 deaths per 100,000 persons during 1988 to 1992 and 1993 to 1997 time periods, respectively. Mortality rates have increased in both the white and non-white populations over the 15-year study period, with the most pronounced increases among the non-white population. CONCLUSION: Asthma mortality rates in Louisiana have increased, particularly among the non-white population, over the last 15 years, although the results are not statistically significant. When compared with other states, asthma mortality in Louisiana is lower than in the northeast and central north states.  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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10.
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   
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