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排序方式: 共有1522条查询结果,搜索用时 15 毫秒
1.
目的 建立蒙药绿松石的质量标准。方法 收集不同产地绿松石,共10批。观察绿松石样品和粉末的性状并进行理化鉴别;按2020年版《中国药典》(四部)通则方法测定绿松石样品中水分、浸出物含量;采用原子吸收光谱法测定绿松石样品铜元素含量。结果 绿松石为不规则、周围带有黑石的块状物,表面蓝绿色,体重,质硬脆,难砸碎,断面呈贝壳状,蜡样光泽,粉末呈灰绿色,无臭,味淡;理化鉴别结果显示,呈铜盐反应;10批次样品中水分含量为0.41%-3.94%(SD=1.37%),浸出物含量为0.21%-0.81%(SD=0.21%),铜元素含量为3.03%-4.63%(SD=0.63%)。结论 初步拟定绿松石中水分含量不得超多5.0%、浸出物含量不得低于0.10%,铜元素含量应为2.60%-4.84%,制定的标准可用于蒙药材绿松石的质量控制。  相似文献   
2.
目的 观察优克龙 (Urocalun )治疗输尿管结石的疗效和安全性。 方法 对 6 0例输尿管结石直径 <1cm的患者予口服优克龙治疗 ,4 5 0mg/次 ,3次 /d ,服药 5周。 结果  6 0例患者中结石排出 4 5例 (75 % ) ;10例 (17% )结石位置下降 ;5例 (8% )位置无变化。 4例患者服药后有轻度胃部不适、恶心或口干。 结论 优克龙治疗输尿管结石效果良好。  相似文献   
3.
目的 通过彩色多普勒超声心动图 (CDUCG)和核磁共振成像 (MRI)诊断主动脉夹层动脉瘤 (AD)的影像学特征 ,比较两种无创检查技术诊断AD的临床价值。方法 对临床疑诊AD的患者行CDUCG心脏各切面探查 ,重点扫查并测量主动脉各节段异常超声征象 (夹层发生部位、内膜片跨度、管径宽度等 ) ,对相同患者行MRI检查时在扫描图像上辨认并确定夹层发生的部位、撕裂范围等。结果 CDUCG诊断Ⅰ型AD 4例 ,Ⅱ型 2例 ,Ⅲ型AD 1例。MRI对Ⅰ、Ⅱ、Ⅲ型AD均可明确诊断。本文 3例Ⅲ型AD经MRI确诊并检出附壁血栓 2例 ,1例Ⅰ型AD可疑 ,余结果同CDUCG。结论 两种技术诊断AD各有优缺点 ,CDUCG偏重于诊断Ⅰ、Ⅱ型 ,MRI适合各型AD的诊断。前者更为迅速、直观 ,重复性强 ,可了解心血管病变的全部信息 ;危急重症患者不宜或难以接受MRI检查。  相似文献   
4.
Type II collagen (CII) is of immunological interest because of its repetitive structure and properties as an autoantigen. The mouse gene has recently been cloned, thus enabling T cell-defined epitopes to be identified. Multiple novel epitopes on mouse CII are here detected in the autoreactive T cell response. The major response is directed to an epitope with residues 707-721 located on the CB10 fragment. Some 25 other epitopes are also recognized, including the autologous homologue of the 256-270 epitope which dominates in the response to foreign collagen. The cells reactive with mouse collagen peptides were of Th1 type, as judged by release of IFN-gamma. No significant reactivity was detected to mouse CII peptides during ongoing disease. Alignment of the mouse epitopes revealed a sequence motif with characteristic side chains at residues P1, P4 and P7, and to a lesser extent at P5, within a nonamer core sequence. Binding of these epitopes was simulated in a computer model of the I-Aq molecule, where peptides with anchor residues at P1, P4 and P7 were indeed found to fit the binding groove best. The spacing of pockets and the fine structure of the binding surface of the I-Aq molecule meshes with the repetitive structure of the collagen (X-Y-Gly), thus providing a likely explanation for the occurrence of multiple epitopes. Comparison with human DR binding motifs showed that the I-Aq motif resembles most closely that of the DR4 subtypes which predispose for rheumatoid arthritis.   相似文献   
5.
Evaluation of an on-line patient exposure meter in neuroradiology   总被引:1,自引:0,他引:1  
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6.
7.
目的:探讨α1肾上腺素能受体阻滞剂萘哌地尔(Naftopidil)治疗慢性非细菌性前列腺炎的有效性及安全性。方法:采用开放、自身对照、多中心的临床试验方法,应用萘哌地尔25mg,每日1次,对106例慢性非细菌性前列腺炎(NBP)患者进行了为期4周的治疗。以美国国立卫生院慢性前列腺炎症状评分(NIHCPSI)、前列腺液(EPS)WBC计数及最大尿流率(MFR)为疗效指标,对其有效性及安全性进行观察。结果:服药4周后,可评价病例105例。全组患者NIHCPSI总评分治疗前后平均减低12.0分(P<0.001),症状评分平均减低7.9分(P<0.001),生活质量评分平均减低4.1分(P<0.001)。EPS中WBC计数治疗前及治疗后分别为(15.2±15.1)、(9.5±12.0)个/HP(P<0.01)。MFR治疗前及治疗后分别为(19.2±4.8)、(22.7±4.9)ml/s(P<0.01)。按症状改善评价,治愈2例(1.9%),显效32例(30.5%),有效55例(52.4%),无效16例(15.2%)。总显效率为32.4%,总有效率为84.8%。3例有轻度头晕,1例食欲不佳,不良事件发生率3.81%。结论:萘哌地尔治疗慢性非细菌性前列腺炎安全、有效。  相似文献   
8.
BACKGROUND: Cannabinoids present neurotoxic and neuroprotective properties in in vitro studies, inconsistent alterations in human neuroimaging studies, neuropsychological deficits, and an increased risk for psychotic episodes. METHODS: Proton magnetic resonance spectroscopy ((1)H-MRS), neuropsychological testing, and hair analysis for cannabinoids was performed in 13 male nontreatment-seeking recreational cannabis users and 13 male control subjects. RESULTS: A significantly diminished N-acetylaspartate/total creatine (NAA/tCr) ratio in the dorsolateral prefrontal cortex (DLPFC) was observed in cannabis users (p = .0003). The NAA/tCr in the putamen/globus pallidum region correlated significantly with cannabidiol (R(2) = .66, p = .004). Results of the Wisconsin Card Sorting test, Trail making Test, and D2 test for attention were influenced by cannabinoids. CONCLUSIONS: Chronic recreational cannabis use is associated with an indication of diminished neuronal and axonal integrity in the DLPFC in this study. As chronic cannabis use is a risk factor for psychosis, these results are interesting because diminished NAA/tCr ratios in the DLPFC and neuropsychological deficits were also reported in schizophrenia. The strong positive correlation of NAA/tCr and cannabidiol in the putamen/globus pallidum is in line with neuroprotective properties of cannabidiol, which were also observed in in vitro model studies of Parkinson's disease.  相似文献   
9.
目的 :研究低发病的中国汉族人群维生素D受体基因 (VDRG)BsmⅠ 位点单核苷酸多态性 (SNP)与前列腺癌的关系 ,探讨不同种族前列腺癌发病的基因差异。 方法 :收集中国北方地区汉族人群 10 3例前列腺癌病人及10 6例健康对照者外周血标本 ,应用变性高效液相色谱 (DHPLC)检测VDRG第 8内含子BsmⅠ多态位点 ,并对该位点SNP分布进行分析。 结果 :BsmⅠ 多态位点bb、Bb、BB基因型和等位基因在北方地区汉族前列腺癌病人及对照者中的分布频率差异无显著性 (P >0 .0 5 ) ,基因型分布频率分别为 92 .2 3%、7.77%、0和 94.34 %、5 .6 6 %、0 ;等位基因B、b分别为 3.88%、96 .12 %和 2 .91%、97.0 9%,而与高发病人群的分布相比有显著不同。 结论 :VDRGBsmⅠ多态性在低发病的中国汉族人群与前列腺癌无相关 ,其分布与高发病人群有明显差异 ,提示VDRGBsmⅠ多态性可能是前列腺癌发病种族差异的原因之一。  相似文献   
10.
While an unstable CTG triplet repeat expansion is responsible for myotonic dystrophy, the mechanism whereby this genetic defect induces the disease remains unknown. To detect proteins binding to CTG triplet repeats, we performed bandshift analysis using as probes double- stranded DNA fragments having CTG repeats [ds(CTG)6-10] and single- stranded oligonucleotides having CTG repeats ss(CTG)8 or RNA CUG triplet repeats (CUG)8. The source of protein was nuclear and cytoplasmic extracts of HeLa cells, fibroblasts and myotubes. Proteins binding to the double-stranded DNA repeat [ds(CTG)6-10], were inhibited by nonlabeled ds(CTG)6-10, but not by a non-specific DNA fragment (USF/AD-ML). Another protein binding to ssCTG probe and RNA CUG probe was inhibited by nonlabeled (CTG)8 and (CUG)8. Nonlabeled oligos with different triplet repeat sequences, ss(CAG)8 or ss(CGG)8, did not inhibit binding to the ss(CTG)8 probe. However, when labeled as probes, the (CAG)8 and (CGG)8 bound to proteins distinct from the CTG proteins and binding was inhibited by nonlabeled (CAG)8 or (CGG)8 respectively. The protein binding only to the RNA repeat (CUG)8 was inhibited by nonlabeled (CUG)8 but not by nonlabeled single- or double-stranded CTG repeats. Furthermore, the CUG-BP exhibited no binding to an RNA oligonucleotide of triplet repeats of the same length but having a different sequence, CGG. The CUG binding protein was localized to the cytoplasm, whereas dsDNA binding proteins were localized to the nuclear extract. Thus, several trinucleotide binding proteins exist and their specificity is determined by the triplet sequence. The novel protein, CUG-BP, is particularly interesting since it binds to triplet repeats known to be present in myotonin protein kinase mRNA which is responsible for myotonic dystrophy.   相似文献   
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