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41.
A chiral poly(3-substituted isobutyl D -aspartate) 12 was synthesized by polymerization of the chiral β-lactam 11 derived from D -glyceraldehyde. The new polyamide was characterized by elemental analyses, and infrared, 1H- and 13C nuclear magnetic resonance spectroscopies. The molecular weight was estimated as 543 000 and 230 000 on the basis of viscosimetric measurements and gel-permeation chromatography, respectively. Polyamide 12 is soluble in a variety of organic solvents including chloroform.  相似文献   
42.
目的:毛细管电泳法测定酮康唑霜中酮康唑和特美味的含量。方法:分离缓冲液为胆汁酸钠(70 mmol/L)-三羟甲基氨基甲烷-磷酸(50 mmol/L)(pH 8.14),分离电压30 kV、温度25 C、50 μm(内径)×48.5cm(有效长度40cm)空心熔融石英毛细管柱、检测波长240nm。结果:以丙酸睾酮为内标,酮康唑质量浓度在140.5~702.5 μg/ml、特美呋质量浓度在151~755μg/ml之间成良好的线性关系;加样回收率分别为95.4%~103.9%、95.9%~102.6%,RSD%分别为2.8%~4.2%(n=3)、2.9%~3.6%。结论:本法简便、快速、可靠,可用于该复方制剂中酮康唑及特美呋的含量测定。  相似文献   
43.
目的:获得SENV-D亚型ORF1-C端蛋白基因序列,并进行表达,为进一步研究及诊断、治疗应用奠定基础.方法:用PCR法从SENV阳性血清中获得SENV-DORF1C端基因,测序验证后,构建了pQE30-SENV-D重组表达质粒,并经过转化E.coli M15,IPTG诱导表达,Western blot分析表达结果.结果:获得了正确序列的SENV-D亚型ORF1-C端蛋白基因序列,表达出Mr约为38×103的蛋白.表达蛋白能与患者血清中相应的抗体结合,发生抗原抗体反应.结论:成功获得并表达了SENV-D-ORF1-C端蛋白,并经Western blot印迹法证实能与阳性血清中的抗体发生抗原抗体反应,有可能用于检测SENV-D抗体.为今后进一步研究有助于疫情监测及早期发现感染者的抗体奠定了坚实的基础.  相似文献   
44.
The PIM357 satellite DNA family is present in 26 Pimelia taxa (Tenebrionidae, Coleoptera) with endemic congeneric species from the Canary Islands showing higher interrepeat variability than continental ones. In this paper, we compare the repetitive DNA sequences of a Canarian species that has distinct subfamilies of repeat units, P. radula ascendens, with another without such subfamilies, P. sparsa sparsa. The chromosomal localization of the repeat units and the comparison of the variability of randomly cloned monomers to the one estimated by comparing repeat units from dimers and trimers suggest the absence of satellite subfamilies in P. sparsa sparsa. Hence, the repeat units of this species seem to be uniformly and randomly distributed throughout all chromosomes out of one chromosomal pair. On the contrary, P. radula ascendens shows four divergent subfamilies of repeat units supported by several diagnostic nucleotide substitutions. These subfamilies seem to form four distinct repeat units: monomer subfamily 1, monomer subfamily 4 and two higher-order units (dimer linking subfamily 1 and 4, and dimer linking subfamily 2 and 3). Moreover, monomers of subfamily 1 are present in three chromosomal pairs only. We discuss the effect of different potential factors acting in the concerted evolution and the genomic organization of stDNA sequences in these taxa. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
45.
46.
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   
47.
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   
48.
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   
49.
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   
50.
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