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61.
鹿衔草化学成分的研究:羟基肾叶鹿蹄草甙的结构鉴定   总被引:9,自引:0,他引:9  
从鹿衔草(Pyrola calliantha H.Andres)分离得到两个化合物。经光谱分析,确定其中1个化合物为新化合物,命名为羟基肾叶鹿蹄草甙(1, hydroxylrenifolin),另一化合物为儿茶素(3)。  相似文献   
62.
63.
Summary Isoamylase-hyperproducing strains of Pseudomonas amyloderamosa were bred by mutagenesis with UV light and N-methyl-N-nitro-N-nitrosoguanidine (NTG). The selection criterion for such strains was based on the formation of large turbid zones around the bacterial colonies in agar medium containing antibiotics and 1% waxy corn starch. Mutant WN6410 was obtained by treating P. amyloderamosa JD210 with five cycles of 1 × 104 J UV light and one cycle of NTG. P. amyloderamosa WN6410 had 22-fold increase in isoamylase activity when compared to wild-type strain SB15 and the maximal enzyme activity, 5,100 U/ml, could be achieved within 48 h in 2.5 L fed-batch fermentation.  相似文献   
64.
我国乙型肝炎患者乙肝病毒前核心基因的分析   总被引:1,自引:0,他引:1  
卫清  张菁 《病毒学报》1994,10(1):63-67
  相似文献   
65.
用修饰核心基因产物干扰乙型肝炎病毒基因的复制和表达   总被引:1,自引:0,他引:1  
  相似文献   
66.
不同钾水平对钾饥饿墨兰碳水化合物和蛋白质含量的影响   总被引:5,自引:1,他引:4  
墨兰(Cymbidiumsinense(Andr.)Willd)植株经过钾饥饿后,无上栽培于不同钾浓度的培养液中.随着钾浓度的升高(5mmol/L),体内可溶性糖、淀粉、纤维素和蛋白质含量比对照分别增加125、117、127和41%,而还原糖和游离氨基酸含量则比对照分别下降44%和24%.假球茎是贮藏还原糖、可溶性糖、淀粉、游离氨基酸和蛋白质的主要器官,叶片是纤维素最多的器官.钾供应充足时,叶片丙酮酸激酶活性明显加强(比对照强15倍),而硝酸还原酶活性也加强(比对照强0.8倍).本文对钾促进墨兰生长发育和抗病等原因加以讨论.并初步提出诊断墨兰体内钾状况的三种生理指标.  相似文献   
67.
从对照和用DEHP处理的大鼠肝脏提取核蛋白,以含酰基CoA氧化酶(AOX)基因表达调控部位的DNA片段和该基因的不同蛋白结合位点的DNA片段作为核蛋白结合反应的探针,通过凝胶电泳迁移率改变实验和Southwestern印迹分析检查了DEHP对AOX基因反式作用因子的影响。结果表明,降血脂药物DEHP可显著增加AOX基因反式作用因子的含量和(或)与基因的结合活性,在转录水平上促进基因的表达。  相似文献   
68.
Microinjection of a dominant interfering mutant of Ras (N17 Ras) caused a significant reduction in thyrotropin (thyroid-stimulating hormone [TSH])-stimulated DNA synthesis in rat thyroid cells. A similar reduction was observed following injection of the heat-stable protein kinase inhibitor of the cyclic AMP-dependent protein kinase. Coinjection of both inhibitors almost completely abolished TSH-induced DNA synthesis. In contrast to TSH, overexpression of cellular Ras protein did not stimulate the expression of a cyclic AMP response element-regulated reporter gene. Similarly, injection of N17 Ras had no effect on TSH-stimulated reporter gene expression. Moreover, overexpression of cellular Ras protein stimulated similar levels of DNA synthesis in the presence or absence of the heat-stable protein kinase inhibitor. Together, these results suggest that in Wistar rat thyroid cells, a full mitogenic response to TSH requires both Ras and cyclic APK-dependent protein kinase.  相似文献   
69.
本文报道在我国广西隆林壮族中发现一个罕見的HbQ复合α,β地中海贫血家系。先证者女,18岁,贫血面容,肝脾肿大。化学结构分析确证本Hb变异体为HbQ Thailand[α74(EF3)Asp→His]。血红蛋白组成以及α和β珠蛋白基因分析结果表明,先证者的珠蛋白基因型为-α~Q/-α~T复合β°/β°(IVSI-1G→T/Codon17A→T);先证者父的基因型为-‘α~Q/-复合β~O/β~A(IVSI-1G→T/β~A);先证母的基因型为-α~T/αα复合β~O/β~A(Codon17A→T/β~A)。  相似文献   
70.

Background

The treatment of Helicobacter pylori (H. pylori) infection is a challenge for those who cannot use amoxicillin.

Objective

To evaluate the eradication rate and adverse effects of vonoprazan and tetracycline dual therapy as first-line and rescue treatment regimens used in special populations with penicillin allergy or failed in previous amoxicillin-containing therapies.

Design

Patients enrolled were those who were H. pylori-positive with selected conditions: (1) allergic to penicillin, either naïve to treatment or had failed before; or (2) failed in previous amoxicillin-containing therapies. All enrolled patients accepted 14-day vonoprazan and tetracycline dual therapy (VT dual therapy) as follows: vonoprazan (20 mg b.i.d.) and tetracycline (500 mg t.i.d. [body weight < 70 kg] or 500 mg q.i.d. [body weight ≥ 70 kg]). H. pylori status was evaluated by 13C-urease breath test 6 weeks after treatment. All adverse effects were recorded. Some patients underwent bacterial culture and antibiotic susceptibility testing.

Results

A total of 62 patients were enrolled; 18 of them received VT dual therapy as first-line treatment, 44 patients received VT dual therapy as rescue treatment. Overall, 58 of 62 patients achieved successful eradication (93.5%), while all involved (100%,18/18) succeeded in the first-line treatment group and 40 cases (90.9%, 40/44) succeeded in the rescue treatment group. Sixty-one (61/62, 98.4%) patients completed the whole course of treatment. Adverse events occurred in 6 patients (6/62, 9.7%), while one patient quit because of skin rash. All adverse effects were mild and relieved spontaneously after H. pylori treatment. Five patients achieved successful H. pylori culture, and all strains isolated were sensitive to tetracycline.

Conclusions

For the treatment of H. pylori infection in special populations with penicillin allergy or failed in previous amoxicillin-containing therapies, a 14-day vonoprazan and tetracycline dual therapy was effective and safe as first-line and rescue treatment in our study. Further study is warranted to verify its efficacy, especially for those who cannot use amoxicillin.  相似文献   
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