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金银花nrDNA ITS区聚合酶链反应条件的研究   总被引:1,自引:0,他引:1       下载免费PDF全文
目的:金银花nrDNA ITS区序列G C含量为68%,用常规的PCR方法扩增效果差.本研究通过改变扩增程序及使用改性剂的方法显著提高了金银花nrDNA ITS区的扩增效率.方法:分别从金银花叶及药材中提取总DNA,通过优化扩增条件,对nrDNA ITS区进行扩增,并比较了两种优化方法的差别及适应性.方法1:提高变性温度至97℃;方法2:添加混合改性剂(DMSO 4%-甘油10%).结果:与方法1相比,方法2可降低变性温度5 ℃,升高退火温度9 ℃,降低镁离子浓度至0.5 mmol/L,降低Taq DNA聚合酶用量至0.1 U(30 μl体系),PCR产物量显著提高,且可消除植物DNA粗提物中杂质的干扰.结论:通过提高退火温度及添加改性剂可克服高G C含量金银花nrDNA ITS区序列扩增的困难,该方法的建立有助于解决植物来源DNA模板的PCR扩增问题.  相似文献   
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It is unclear whether single and combined pharmacologic inhibition of the renin-angiotensin-aldosterone system have similar effects on endothelial function and blood pressure (BP). The authors evaluated 63 hypertensive patients divided into 4 groups (hydrochlorothiazide 25 mg/d; irbesartan [IRBE] 150 mg/d; quinapril [QUIN] 20 mg/d; or IRBE 150 mg/d + QUIN 20 mg/d) and 25 healthy normotensive subjects (normal) followed for 12 weeks. Endothelium-dependent dysfunction measured as flow-mediated dilation at Weeks 0 and 12 were: normal, 11.5%±2.4% vs 13.5%±2.0%; hydrochlorothiazide, 7.3%±2.0% vs 12.8%±3.1%; QUIN, 7.2%±2.8% vs 13.2%±2.1%; IRBE, 7.1%±2.8% vs 13.0%±2.9%; and IRBE + QUIN, 7.5%±1.9% vs 12.8%±3.0%. Nitroglycerin-mediated responses were: normal, 26.0%±1.9% vs 24.0%±2.5%; hydrochlorothiazide, 17.0%±2.2% vs 18.3%±2.6%; QUIN, 17.8%±3.2% vs 23.4%±3.0%; IRBE, 16.8%±3.6% vs 24.7%±2.0%; and IRBE + QUIN, 17.3%±3.0% vs 25.1%±2.5%. Antihypertensive therapy restored BP to normal and improved the endothelium-dependent and -independent dysfunction after renin-angiotensin-aldosterone system blockade. In a further finding, the combined effect of angiotensin-converting enzyme inhibition and angiotensin II type 1 receptor blockade was not superior to the action of either of these treatments separately.  相似文献   
124.
The aim of this research was to quantify sleep problems in patients suffering from Parkinson's disease by means of the new Parkinson's Disease Sleep Scale (PDSS) and to correlate such problems with the possible influence of current drug treatment. A total of 70 patients (36 men and 34 women) with a diagnosis of Parkinson's disease were enrolled. Their mean age was 69.7 +/- 8.2 years, and duration of disease was 7.4 +/- 4.8 years. All patients completed the PDSS and the Unified Parkinson's Disease Rating Scale (UPDRS Parts I-IV). Drug consumption and doses were registered. The mean score on the PDSS scale was 109.23 +/- 19.75 and on the UPDRS III scale was 25.24 +/- 11.35. The lowest scores were obtained in Item 3 (sleep fragmentation): 5.53 (2.46); and in Item 8 (nocturia): 5.75 (2.91). There was a weak correlation between the PDSS and UPDRS III (cc = -0.355, P = 0.003), PDSS and UPDRS I (cc = -0.272, P = 0.02), and PDSS and UPDRS IV (cc = -0.416, P < 0.001). Motor conditions, mental state, and drug complications influence sleep quality. Although this effect was significant, it was not of a great magnitude. Dopaminergic drugs did not increase daytime sleepiness. As a whole, sleep quality in patients who took dopaminergic agonists did not differ from that of patients who took levodopa in monotherapy.  相似文献   
125.
经直肠超声引导前列腺穿刺活检203例临床分析   总被引:8,自引:1,他引:7  
目的评估经直肠超声引导的前列腺六针穿刺活检在前列腺癌及前列腺其他疾病的诊断和鉴别诊断的价值。方法对指肛检查阳性,血清PSA〉4pg/L及经直肠超声检查前列腺声像图异常怀疑有占位性病变的203人进行经直肠超声引导的前列腺穿刺活检。结果穿刺活检的203例病理结果:良性前列腺增生(BPH)104例占51.24%,前列腺癌(PCa)95例占46.80%,前列腺结核及前列腺平滑肌肉瘤各2例,分别占0.98%。结论经直肠超声引导的前列腺穿刺活检其操作简单,病人痛苦小,并发症少,较安全。在前列腺癌及其他前列腺疾病的诊断与鉴别诊断中有重要的临床价值。  相似文献   
126.
Objective:  This study determined the clinical predictors of suicidal behavior during a 2-year follow-up of patients with bipolar disorder presenting with a major depressive episode (MDE).
Method:  Sixty four patients with DSM-III-R bipolar disorder were assessed at presentation for treatment of an MDE. Correlates of past suicidal behavior were determined by comparing patients with and without a history of suicide attempts using a t -test, Wilcoxon test or chi-squared test of independence on individual explanatory variables. Putative predictors of attempts during the follow-up period were tested separately using Cox proportional hazards regression analysis.
Results:  Twelve of 64 patients had at least one suicide attempt in the follow-up period, five of them attempted in the first 2 months and seven around or shortly after the 1-year follow-up visit. All attempters had a history of past suicide attempts. Most predictors of future suicidal behavior were correlates of past suicidal behavior. Family history of suicide acts and comorbid borderline personality disorder predicted early attempts, while younger age, high hostility scores, number of past attempts, subjective pessimism as reflected in depression and suicidal ideation, and few reported reasons for living predicted suicidal acts during the whole period.
Conclusion:  In this data set of bipolar patients we noted an intriguing picture of two clusters of suicide attempts. Hostility was the strongest risk factor. These findings may have implications in both the identification of at-risk patients and the timing of clinical interventions including aggressive pharmacotherapeutic prophylaxis to prevent relapse or recurrence of depressive symptomatology.  相似文献   
127.
腹腔内疝的CT表现   总被引:2,自引:1,他引:1  
腹腔内脏器穿过腹膜或膜突入另一腹腔内间隙称为腹腔内疝(internal abdominal hernias)。最常表现为一段小肠嵌入正常或异常的腹腔内孔道,引起急性小肠梗阻。作为疝口的结构可以是腹腔内的正常解剖结构,如裂孔、隐窝、陷窝等,  相似文献   
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129.
美国处理医疗损伤责任纠纷的法律程序   总被引:1,自引:0,他引:1  
不论是一般的民事或刑事案件,还是医疗损伤责任案件,法律的具体实施程序实际上都是一个个独立的决策过程。本文介绍了美国医疗损伤责任纠纷的法庭外解决方式、医疗损伤责任纠纷的法庭诉讼程序和其他与医疗损伤责任纠纷相关的法律。  相似文献   
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