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Z M Huang D Thewke Q Q Gong D Schlichter W D Wicks 《Brain research. Molecular brain research》1991,11(3-4):309-319
Transient transfection of pLB2CAT constructs bearing short synthetic oligonucleotides derived either from the tyrosine hydroxylase (TH) promoter or other sources was used to examine functional cAMP regulatory element (CRE) activity in a variety of cell lines. The region containing only the putative TH CRE was found to be as or more effective in conferring cAMP responsiveness onto pLB2CAT (which employs the TK promoter) than the immediate 272 bp region of the TH promoter. Increases in CAT activity of 10- to 20-fold were observed in JEG-3 cells with a single insert of the TH CRE region (-31 to -54) in pLB2CAT, and the presence of a second insert generated only a modest further increase. This construct also responded to cAMP in 4 other cell lines tested but the degree of increase was less dramatic. Inserts containing the consensus 8 bp CRE motif embedded in other natural or artificial contexts served generally as weak functional CREs in all cell lines tested. In vitro analysis revealed that a specific protein-DNA complex apparently containing a single protein with a MW of 45-50 kDa was formed equally well with JEG-3 cell nuclear extract and CRE-bearing-TH and other fragments which produced dramatically different cAMP effects in vivo. These results suggest specificity in the effects of cAMP on different CREs which are dictated by contextual differences. 相似文献
3.
病理技术质量控制的探讨 总被引:2,自引:0,他引:2
病理技术是病理学诊断不可分割的一部分,正确的染色结果是病理诊断的重要依据之一.病理技术的规范与否,制片质量的好坏很大程度上影响病理医生作出正确的病理诊断. 相似文献
4.
冠状动脉搭桥术193例经验总结 总被引:2,自引:0,他引:2
目的:探讨冠状动脉搭桥术的病例选择、手术方法和治疗效果。方法:回顾性分析1997年1月~至2003年12月齐鲁医院施行的体外循环下冠状动脉搭桥术穴CPBCABG雪99例,非体外循环冠状动脉搭桥术穴OPCABG雪74例,冠状动脉搭桥加瓣膜置换术穴CABG VP雪20例的临床资料。结果:手术死亡6例,死亡率3.1%。体外循环下单纯冠状动脉搭桥术死亡率为2%,非体外循环冠状动脉搭桥术死亡率为2.7%,冠状动脉搭桥加瓣膜置换术死亡率为10%。短期随访3~6个月,症状消失占93.0%,症状明显减轻占5.4%。结论:患者近期随访效果良好,3组的手术死亡率差异无统计学意义穴P>0.05雪。 相似文献
5.
复发性鼻腔及鼻窦恶性肿瘤的挽救性治疗 总被引:1,自引:0,他引:1
目的 探讨鼻腔及鼻窦恶性肿瘤复发后的临床表现、与复发有关的因素、再手术的意义及缺损组织的修复。方法 排除原发性鼻腔鼻窦恶性肿瘤,仅收集治疗后复发并且有再手术意义的病例。应用乘积极限法估计生存率,Stata7.0统计软件进行统计运算。结果 1993~2002年共有25例患者符合要求。男19例,女6例,年龄13~66岁,平均46.1岁。所有患者均有至少1次手术或放射治疗史。末次治疗至复发的时间2周~46个月,中位时间18个月,80%的患者肿瘤复发出现于末次治疗后2年内。术后随访1~65个月。再手术中无死亡病例。5例健在无肿瘤复发;局部复发2例,颈部淋巴结转移1例,经过1刀或手术治疗后2例健在、1例带瘤生存;死于局部复发13例,死于肺转移1例,死于无关疾病1例,失访2例。1年生存率62.5%,2年生存率43.7%,3年生存率29.1%,中位生存时间18个月。术后发生脑脊液漏3例次,中枢性尿崩症1例次,皮瓣部分坏死1例次。手术修补脑脊液漏l例。结论 鼻腔及鼻窦恶性肿瘤局部复发多发生于末次治疗后2年之内,主要症状是头痛及局部隆起。肿瘤的类型和分化程度与复发密切相关。合理、及时的综合治疗有助于减少复发。运用有效修复手段的再手术可改善晚期患者的生活质量,延长生命。并发症主要是脑脊液漏,多数可通过保守方法治愈。 相似文献
6.
穿透性角膜移植联合瞳孔成形术的临床观察 总被引:1,自引:0,他引:1
目的观察穿透性角膜移植联合瞳孔成形术的效果。方法48只眼行穿透性角膜移植术的同时对虹膜缺损进行修复,成形瞳孔。术后随访6~89个月。结果植片透明者38只眼(79.2%),视力恢复0.1以上者31只眼(64.6%),瞳孔修复接近正常者43只眼(89.6%)。结论穿透性角膜移植联合瞳孔成形术,可减少术后并发症、改善植片的预后及视功能。对波及瞳孔的虹膜缺损,联合行瞳孔成形术效果较好。 相似文献
7.
M P Sherman M D Roth H Gong D P Tashkin 《Pharmacology, biochemistry, and behavior》1991,40(3):663-669
Pulmonary alveolar macrophages lavaged from tobacco smokers release increased levels of oxidants and have been implicated in the pathophysiology of emphysema. It is unknown whether lung macrophages recovered from marijuana smokers also liberate excessive levels of oxidants. To evaluate this possibility, pulmonary alveolar macrophages were obtained by bronchoalveolar lavage from nonsmokers, smokers of marijuana only, smokers of tobacco only, and smokers of tobacco plus marijuana. Spontaneous and stimulated superoxide anion release was measured by the superoxide dismutase-inhibitable reduction of ferricytochrome c. These findings were correlated with recent lung function tests. Superoxide anion production by macrophages, studies of small airway integrity (closing volume, closing capacity, and the slope of Phase III of the single-breath nitrogen washout curve), and evaluation of alveolar gas exchange (diffusing capacity of carbon monoxide) were similar in both nonsmokers and marijuana smokers. However, tobacco smoking was associated with both significantly higher levels of superoxide anion release by pulmonary alveolar macrophages and significant abnormalities of small airway function and alveolar diffusing capacity. Based on the results of this study, pulmonary alveolar macrophages of marijuana-only smokers do not produce increased amounts of oxidants when compared to macrophages of non-smoking subjects. This observation may account for the absence of abnormalities in small airway function and alveolar diffusing capacity in marijuana-only smokers, in contrast to the presence of such findings in smokers of tobacco, regardless of marijuana use. 相似文献
8.
M.S. Ågren U. Ostenfeld M.E. Crawford K. Kiss Y. Gong C. Gluud A. FriisMøller F. Kallehave K. Raffn L.N. Jorgensen 《Wound repair and regeneration》2005,13(2):A1-A27
Extended healing time and lack of documented effective treatments of sacrococcygeal pilonidal disease create substantial problems. Locally applied zinc oxide has been reported to promote wound healing. We have compared topical zinc oxide (3%) with placebo meshes for pilonidal wounds healing by secondary intention in a randomized, double‐blind, placebo‐controlled multicenter trial. Sixty‐four consecutive patients, 53 males, aged between 18 and 60 years (median 26 years) with excised pilonidal wounds were centrally randomized to local zinc oxide (30 mg/g, n = 33) or to placebo (n = 31) mesh treatment. Patients were followed with strict recording of beneficial and harmful effects. The median healing times were 54 days (42–71 days, interquartile range, n = 33) for the zinc group and 62 days (55–82 days, n = 31) for the placebo group. This difference was not statistically different (p = 0.32). Based on Cox regression analysis initial wound volume influenced healing negatively (p = 0.016) while smoking (p = 0.011) was associated with faster wound healing. Significantly (p < 0.01) more placebo (n = 12) than zinc oxide‐treated patients (n = 3) needed antibiotics postoperatively. Although topical zinc oxide increased (p < 0.001) wound fluid zinc levels (1830 ± 405 μM, mean ± SEM) compared with placebo (3.1 ± 1.6 μM) serum‐zinc levels did not differ significantly between the zinc (13.5 ± 0.4 μM) and placebo (12.8 ± 0.4 μm) groups on postoperative day 7. No adverse events were recorded. Topical zinc oxide treatment did not accelerate time to closure of open pilonidal wounds but was associated with reduced antibiotic usage. 相似文献
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龚燕平 《世界急危重病医学杂志》2005,2(6):995-995
一位有酒精依赖病史的61岁老年女性因酒精中毒被送到急诊科,其血浆酒精浓度为322mg/dl。她承认因为发胶中非自然的的酒精成分,她混水应用了一瓶14盎司的发胶。最初她在参加一次酒精匿名会议时学会了这种应用非饮料酒精的方法,为了向家人隐瞒滥用酒精的事实,她开始应用并持续了数年。她应用的发胶的非自然酒精含量高达50%.其吸收量约为7盎司酒精,相当于141.25盎司80标准强度的酒精饮料。 相似文献