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51.
52.
目的 评估AO圆捧内固定系统(VentroFix)在胸腰椎结核前路病灶彻底切除植骨内固定术中的临床应用价值。方法 对16例胸腰椎结核患者行病灶切除,植骨及应用VentroFix进行内固定。结果 16例经9~18个月随访,无术中,术后并发症,植骨全部融合,无植骨块移位或塌陷及高度丢失。亦无螺钉断裂无松动等现象,脊髓神经功能均有不同程度的恢复。结论 该固定系统具有固定牢固,稳定性高,操作简单安全,合并症少,生物相容性好,无磁性等优点,是胸腰椎结核良好的前路内固定器械。 相似文献
53.
目的研究高密度脂蛋白-3(HDL3)介导大鼠皮肤成纤维细胞胆固醇(ch)流出机制。方法用N-乙酰咪唑修饰HDL,阻断HDL与细胞受体相互作用,观察其对HDL3介导细胞ch流出的影响。用FITC标记HDL示踪HDL3在介导细胞ch流出中自身代谢过程。结果牛血清白蛋白(对照组)介导4.74%细胞ch流出,HDL3组和N-乙酰咪唑HDL组分别为31.85%和8.41%。FITC-HDL3与细胞37-℃培养3h后,细胞内吞荧光强度(FS)占细胞结合FS的65.78%,其中93.5%FS存在于TCA可沉淀部分。细胞进一步37- 相似文献
54.
目的 制备异丙基肾上腺素对心肌损伤模型 ,探讨辅酶Q10 和复方丹参对心肌线粒体呼吸链的保护作用。方法 采用In cheolKim法和Lucile Smith法分别测定对照组 ,异丙肾损伤组 ,丹参保护组和辅酶Q10 保护组的琥珀酸脱氢酶比活力 ,心肌线粒体辅酶Q10 含量等多项指标。结果 复方丹参组和辅酶Q10 组心肌线粒体琥珀酸脱氢酶比活力 ,心肌线粒体辅酶Q10 含量都显著高于异丙肾组。结论 辅酶Q10 和复方丹参对心肌线粒体呼吸链有明显地保护作用。 相似文献
55.
贵阳城区儿童少年行为问题与家庭背景研究 总被引:5,自引:0,他引:5
为了解贵阳城区儿童少年行为问题的现状和行为问题儿童少年与家庭因素的关系 ,用Achenbach’s儿童行为量表及儿童发展相关因素问卷对贵阳城区 1365名 6~ 16岁儿童青少年进行调查 ,就调查结果进行了现状分析及相关因素的单元和多元比较。结果表明 :检出有行为问题的儿童少年 2 0 7名 ,检出率 ( 15 16± 0 72 ) % ,高于全国调查结果 ,差异有显著性P <0 0 5)。中学组检出率高于小学组 ,差异不明显 ,与其他城市及全国相比差异有显著性 (P <0 0 5)。性别差异不明显。检出率较高的因子是忧郁、社会退缩、多动、攻击等。影响儿童少年行为问题的家庭因素依次是 :家庭对孩子心理健康的重视程度、母亲文化、家庭经济收入、家长对子女心理健康的认识、父母婚姻状况等。提示 :贵阳城区儿童少年行为问题的检出率高于全国水平 ,高年龄组尤为突出。家庭环境是影响儿童少年行为发展的重要因素。 相似文献
56.
天津市汉沽区媒介生物调查初报 总被引:1,自引:0,他引:1
本文报道了天津市汉沽区域媒介生物的调查结果:本地区有蚊类6种;鼠类5种;蝇类31种;蜚蠊类3种;蚤类2种;螨类1种。 相似文献
57.
Ile-269 in horse liver alcohol dehydrogenase isoenzyme S(HLADH-S) was mutated to serine by phosphorothioate-based site-directed
mutagenesis in order to study the role of the residue in coenzyme binding. The specific activity of the mutant(I269S) enzyme
to ethanol was increased 49-fold. All turnover numbers of I269S enzyme toward 9 primary alcohols were increased. The mutant
enzyme showed 3.6, 4.6, 11.6-fold higher catalytic efficiency for 5β-androstane-3,17-dione, 5β-cholanic acid-3-one and retinal
than wild-type, respectively. The reaction mechanism of I269S enzyme was ordered bi bi as wild-type's. These results indicate
that the hydrophobic interaction of Ile-269 residue with coenzyme plays an important role in dissociation of coenzyme from
enzyme-coenzyme complex, which has been known as the rate limiting step of ADH reaction. 相似文献
58.
Le Bihan G Rondu F Pelé-Tounian A Wang X Lidy S Touboul E Lamouri A Dive G Huet J Pfeiffer B Renard P Guardiola-Lemaître B Manéchez D Pénicaud L Ktorza A Godfroid JJ 《Journal of medicinal chemistry》1999,42(9):1587-1603
Piperazine derivatives have been identified as new antidiabetic compounds. Structure-activity relationship studies in a series of 1-benzyl-4-alkyl-2-(4',5'-dihydro-1'H-imidazol-2'-yl)piperazines resulted in the identification of 1-methyl-4-(2', 4'-dichlorobenzyl)-2-(4',5'-dihydro-1'H-imidazol-2'-yl)piperazine, PMS 812 (S-21663), as a highly potent antidiabetic agent on a rat model of diabetes, mediated by an important increase of insulin secretion independently of alpha2 adrenoceptor blockage. These studies were extended to find additional compounds in these series with improved properties. In such a way, substitution of both piperazine N atoms was first optimized by using various alkyl, branched or not, and benzyl groups. Second, some modifications of the imidazoline ring and its replacement by isosteric heterocycles were carried out, proceeding from PMS 812, to evaluate their influence on the antidiabetic activity. The importance of the distance between the imidazoline ring and the piperazine skeleton was studied third. Finally, the influence of the N-benzyl moiety was also analyzed compared to a direct N-phenyl substitution. The pharmacological evaluation was performed in vivo using glucose tolerance tests on a rat model of type II diabetes. The most active compounds were 1,4-diisopropyl-2-(4', 5'-dihydro-1'H-imidazol-2'-yl)piperazine (41a), PMS 847 (S-22068), and 1,4-diisobutyl-2-(4',5'-dihydro-1'H-imidazol-2'-yl)piperazine (41b), PMS 889 (S-22575), which strongly improved glucose tolerance without any side event or hypoglycemic effect. More particularly, PMS 847 proved to be as potent after po (100 micromol/kg) as after ip administration and appears as a good candidate for clinical investigations. 相似文献
59.
A large percentage of human immunodeficiency virus (HIV) patients have serological evidence of a past or present hepatitis B virus infection (HBV). Long-term survival is increasing for HIV patients because of highly active antiretroviral therapy. Therefore, the chronic hepatitis B infection may become an important determinant of disease outcome in these co-infected patients. We describe two HIV/HBV co-infected patients who were treated with extended antiviral therapy, initially indicated for the HIV infection. Lamivudine, a suppressor of viral replication in both infections, was one of these antiviral drugs. One patient showed a severe rebound of the HBV after withdrawal of lamivudine, the other patient developed a mutant hepatitis B virus after 18 months of treatment. This mutation was exclusively induced by lamivudine. These patients show that, with improved HIV-related survival, the HBV infection should be monitored carefully, thereby enabling the physician to interfere with therapy when necessary. 相似文献
60.
Age and gender-related incidence of chronic renal failure in a French urban area: a prospective epidemiologic study 总被引:1,自引:1,他引:0
Jungers P.; Chauveau P.; Descamps-Latscha B.; Labrunie M.; Giraud E.; Man N. K.; Grunfeld J. P.; Jacobs C. 《Nephrology, dialysis, transplantation》1996,11(8):1542-1546
OBJECTIVE.: To determine the age- and gender-related incidence of chronicrenal failure in a French urban area. METHODS.: Prospective study of adult patients newly identified as havingestablished, chronic renal failure defined by serum creatinine(Scr) 200 µmol/l, with the cooperation of all nephrologyand dialysis units in the Ile de France district (10,660,000inhabitants) during a 1-year period. RESULTS.: 2775 patients (1780 males, 995 females) were referred with Scr200 µmol/l between July 1991 and June 1992, an overallincidence of 260/million population. 847 had advanced renalfailure (Scr 500 µmol/l) and 541 patients (19.5%) were75 years of age. The age-related incidence was 92, 264, 523and 619/million population in the age groups 2039, 4059,6074 and 75 years old, respectively. The annual incidencewas twice as high in males than in females up to 75 years andthree times as high in patients 75 years (1124 vs 356/millionpopulation). Based on the proportion of patients reaching end-stagerenal failure within one year of referral, the minimal estimationof the need for supportive therapy is 81/million/year. CONCLUSIONS.: This epidemiological study in a large French urban area indicatesan incidence of 260 patients per million population annuallyreferred to nephrology units for chronic renal failure definedby Scr 200 µmol/l, with a marked preponderance of malesand a dramatic increase of incidence with age in both genders. 相似文献