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1.
利用主客体分子包结现象选择分离蛇床子有效成分的方法   总被引:2,自引:0,他引:2  
利用1,1,6-四苯基-2,4-已二炔-1,6-二醇(I)的包结能力,可简单而迅速地从蛇床子中选择分离出有效成分欧前胡素(2)和花椒毒素(3),收率分别为0.054%(2)和0.002%(3)。本文用UV,IR,1HNMR和13CNMR验证了2和3的化学结构,并用HPLC检验了2和3的纯度。X-射线衍射晶体结构分析表明主体分子I与组分2靠氢键形成包结物,它们的摩尔比为1:2,氢键长为2.8612A。包结物晶体属单斜晶系,空间群为已P21/C,晶胞参数:a=15.468(5)A,b=8.595(3)A,c=18.663(7)A,β=93.64(5)°,Z=4和R=0.088。  相似文献   
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豨莶脂溶性成分的研究   总被引:7,自引:0,他引:7  
从豨莶(Siegesbeckia orientalis L.)的地上部分,分离出八个化合物,其中I和I根据理化性质和光谱数据确定其结构为ent-17-acetoxy-18-isobutyryloxy-16(α)-kauran-19-oicacid(I)和ent-17-ethoxy-16(α)-kauran-19-oicacid(II),均为新化合物,分别被命为豨莶酯酸(siegesesteric acid,I)和豨莶醚酸(siegesetheric acid,I)。其余化合物分别鉴定为腺梗豨莶萜醇酸(ent-16β,17-dihydroxy-kauran-19-oicacid,II),奇任醇(kirenol,IV,β-谷甾醇葡萄糖甙(β-sitosterolglucoside,V),二十一醇(heneicosanol,VI),花生酸甲酯(methyl arachidate,VII)和β-谷甾醇(β-sitosterol,VII)。除奇任醇和β-谷甾醇外,均为首次从该植物中分得。  相似文献   
3.
癌基因c-erbB-2在膀胱移行细胞癌中的扩增   总被引:2,自引:1,他引:1  
赵致广  张莉莉 《医学争鸣》2000,21(4):482-482
0 引言 为探讨癌基因 c- erb B- 2的扩增与膀胱移行细胞癌(TCC)的关系 ,我们以斑点杂交的方法对 40例膀胱 TCC标本中 c- erb B- 2的扩增情况进行了检测 ,以期明确 c- erb B- 2扩增与膀胱 TCC病理分级及患者预后的关系 .1 材料和方法  40例膀胱 TCC患者术后石蜡包埋标本 ,随访 5~ 10 a. 11例正常膀胱粘膜石蜡标本作为对照 . c- erb B-c DNA p CER2 0 4质粒由东京大学提供 ,Bothringer缺口平移 DNA标记试剂盒及 32 P标记 d CTP购于北京福瑞公司 .所有石蜡标本经脱蜡及蛋白酶消化 ,以酚 /氯仿抽提 DNA,乙醇沉淀 .每份样品取…  相似文献   
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BACKGROUND AND AIMS: Serotonin (5-hydroxytryptamine [5-HT]) is a key modulator of gut function that in excess causes nausea, vomiting, and diarrhea. We recently showed that patients with post-infective irritable bowel syndrome have increased postprandial release of 5-HT associated with low-grade T-cell mediated inflammation. Celiac disease is another common disease in which a T-cell enteropathy is associated with increased mucosal 5-HT levels. Our aim was to determine how this inflammatory lesion influenced 5-HT bioavailability and how changes in 5-HT related to the symptoms of nausea, vomiting, and diarrhea seen in untreated celiac patients. METHODS: Fasting plasma and platelet 5-HT and postprandial plasma 5-HT levels were measured after a high-carbohydrate meal in celiac patients (n = 18) and healthy controls (n = 18) using high-pressure liquid chromatography. Dyspepsia was assessed during the postprandial period using a questionnaire. Finally, we compared the histology and mucosal 5-HT levels in duodenal biopsy specimens from celiac patients and controls. RESULTS: Celiac patients had increased 5-HT-containing enterochromaffin cell numbers and significantly higher peak plasma 5-HT levels (P = .0002), postprandial area under the curve (P = .0006), and platelet 5-HT stores (P = .031) than controls. Peak 5-HT levels correlated significantly with postprandial dyspepsia scores (P = .005). Celiac patients had higher duodenal 5-HT levels (P = .007) than controls. CONCLUSIONS: Celiac disease is associated with increased mucosal 5-HT content and enhanced 5-HT release from the upper small bowel, which correlates with postprandial dyspepsia. Serotonin excess may mediate dyspeptic symptoms in untreated celiac disease.  相似文献   
6.
Background and Aim: Nocturnal gastro‐esophageal reflux causes heartburn and sleep disturbances impairing quality of life. Lifestyle modifications, like bed head elevation during sleep, are thought to alleviate the symptoms of gastroesophageal reflux. We tested the hypothesis that bed head elevation might decrease recumbent acid exposure compared to sleeping in a flat bed. Methods: Patients of symptomatic nocturnal reflux and documented recumbent (supine) reflux verified by esophageal pH test entered the trial. On day 1, baseline pH was measured while the patient slept on a flat bed. Then patients slept on a bed with the head end elevated by a 20‐cm block for the next 6 consecutive days from day 2 to day 7. The pH test was repeated on day 2 and day 7. Each patient acted as his own control. Results: Twenty of 24 (83.3%) patients with mean age of 36 ± 5.5 years completed the trial. The mean (± SD) supine reflux time %, acid clearance time, number of refluxes 5 min longer and symptom score on day 1 and day 7 were 15.0 ± 8.4 and 13.7 ± 7.2; P = 0.001, 3.8 ± 2.0 and 3.0 ± 1.6; P = 0.001, 3.3 ± 2.2 and 1.0 ± 1.2; P = 0.001, and 2.3 ± 0.6 and 1.5 ± 0.6; P = 0.04, respectively. The sleep disturbances improved in 13 (65%) patients. Conclusions: Bed head elevation reduced esophageal acid exposure and acid clearance time in nocturnal (supine) refluxers and led to some relief from heartburn and sleep disturbance.  相似文献   
7.
Introduction: Cancer initiating or stem cells (CSCs) are a small population of cells in the tumor mass, which have been reported to be present in different types of cancers. CSCs usually reside within the tumor and are responsible for reoccurrence of cancer. The imprecise, inaccessible nature and increased efflux of conventional therapeutic drugs make these cells resistant to drugs. We discuss the specific markers for identification of these cells, role of CSCs in chemotherapy resistance and use of different therapeutic means to target them, including elucidation of specific cell markers, exploitation of different signaling pathways and use of nanotechnology.

Area covered: This review covers cancer stem cell signaling which are used by these cells to maintain their quiescence, stemness and resistant phenotype, distinct cell surface markers, contribution of these cells in drug resistance, inevitability to cure cancer and use of nanotechnology to overcome this hurdle.

Expert opinion: Cancer stem cells are the main culprit of our failure to cure cancer. In order to cure cancer along with other cells types in cancer, cancer stem cells need to be targeted in the tumor bed. Nanotechnology solutions can facilitate clinical translation of the therapeutics along with other emerging technologies to cure cancer.  相似文献   

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运动中跟腱断裂的原因及预防   总被引:1,自引:2,他引:1  
目的:分析运动中跟腱断裂的原因和发生部位,找到预防的措施。方法:通过检索文献资料、调查访问和临床诊断等方法,对34例在运动中因非外力的原因造成跟腱断裂的个案进行分析。结果:34例全部为在运动中因非外力的原因造成跟腱急性闭合性断裂,其中30例为完全断裂,4例为不完全断裂。损伤的主要原因:①跟腱患有退行性病变,变得脆弱,易断裂。②跟腱部位过度疲劳。③热身活动不足。④技术动作不合理。⑤跟腱的退行性变化提前于肌肉造成的软组织活性不协调。⑥可能的原因:近几年来吃的转基因食品较多或吃的动物肉类所含激素成分较多,造成肌腱脆性增加。34例中有25例为跟腱中部断裂,占74%,即断点在跟腱止点上方3~5cm。34例中28例断端不整齐呈现马尾状,19例曾有慢性跟腱周围炎病史,且年龄平均在40岁以上。断裂部位集中,断裂类型较一致。结论:运动前应充分做好热身活动,防止运动中过度疲劳,严格控制营养素的摄取,尽量少补充含激素成分较多的肉类和转基因食品,以减少跟腱断裂情况的发生。  相似文献   
10.
BACKGROUND: Therapeutic endoscopy has provided a new means of treating bleeding peptic ulcers. Additional medical therapy may enhance the therapeutic benefit. Hemostasis is highly pH dependent and is severely impaired at low pH. Proton pump inhibitors, by achieving a significantly higher inhibition of gastric acidity, may improve the therapeutic outcomes after endoscopic treatment of ulcers. PATIENT AND METHODS: We enrolled 166 patients with hemorrhage from duodenal, gastric, or stomal ulcers and signs of recent hemorrhage, as confirmed by endoscopy. Twenty-six patients had ulcers with an arterial spurt, 41 patients had active ooze, 37 had a visible vessel, and 62 patients had an adherent clot. All patients received endoscopic injection sclerotherapy using 1:10,000 adrenaline and 1% polidocanol and were randomly assigned to receive omeprazole (40 mg orally) every 12 hours for 5 days or an identical-looking placebo. The outcome measures used were recurrent bleeding, surgery, blood transfusion, and hospital stay. RESULTS: Six (7%) of 82 patients in the omeprazole group had recurrent bleeding, as compared with 18 (21%) in the placebo group (P = 0.02). Two patients in the omeprazole group and 7 patients in the placebo group needed surgery to control their bleeding (P = 0.17). One patient in the omeprazole group and 2 patients in the placebo group died (P = 0.98). Twenty-nine patients (35%) in the omeprazole group and 61 patients (73%) in the placebo group received blood transfusions (P <0.001). The average hospital stay was 4.6 +/- 1.1 days in the omeprazole group and 6.0 +/- 0.7 days in the placebo group (P <0.001). CONCLUSION: The addition of oral omeprazole to combination injection sclerotherapy decreases the rate of recurrent bleeding, reduces the need for surgery and transfusion, and shortens the hospital stay for patients with stigmata of recent hemorrhage.  相似文献   
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