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排序方式: 共有2785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
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This study utilizes a psychophysical approach to examine the effects on
carrying capacity for bi-manual carrying tasks involving different handle positions and
carrying ranges. A total of 16 female subjects participated in the experiment in groups of
two people, and each group of subjects performed the tasks in a random order with 12
different combinations of carrying task. The independent variables are handle position
(upper, middle, lower) and carrying range (F–F: floor height carried to floor height, F–W:
floor height carried to waist height, W–W: waist height carried to waist height, W–F:
waist height carried to floor height), the dependent variable is the maximum acceptable
carried weight (MAWC), heart rate (HR), and the rating of perceived exertion (RPE). The
results show that the handle position has a significant effect on MAWC and overall RPE but
no significant effect on HR. Carrying range has a significant effect on the MAWC and HR,
but no significant effect on overall HR. The handle position and carrying range have a
significant interaction on the MAWC and HR. The RPE for different body parts shows
significant differences, and the hands feel the most tired. Overall, this study confirms
that the lower handle position with the W–W carrying range is the best combination for a
two-person carrying task. 相似文献
4.
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
5.
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
6.
Bayrak S; Holmdahl R; Travers P; Lauster R; Hesse M; Dolling R; Mitchison NA 《International immunology》1997,9(11):1687-1699
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
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目的研究正常人眼球运动动态磁共振成像(MRI)4条直肌Pulley(滑车)的功能性位置。方法采用西门子公司Sonata1.5T超导型MRI扫描仪,应用眼球运动动态MRI技术,获取20名正常人(20个眼眶)眼球原在位及上转、下转、内转、外转20度时垂直于眶轴的眼眶冠状位MRI图像。以眼球中心为原点建立三维坐标系,应用ScionImage医学图像测量软件分别测量各层面眼球垂直转动时水平直肌、眼球水平转动时垂直直肌的横截面质心。根据各层面直肌横截面质心的坐标值建立直线回归方程,分别求得眼球垂直转动时内、外直肌径路及眼球水平转动时上、下直肌径路直线回归曲线斜率变化最大的一点,即为该直肌Pulley的功能性位置。对4条直肌Pulley相对于眼球中心的坐标值(X、Y)进行统计。结果内直肌Pulley位于眼球中心后4mm,内14.7mm,下0.3mm;外直肌Pulley位于眼球中心后8mm,外9.8mm,下0.3mm;上直肌Pulley位于眼球中心后6mm,内1.6mm,上11.5mm;下直肌Pulley位于眼球中心后6mm,内4.4mm,下12.7mm。结论应用眼球运动动态MRI技术,分析眼球转动时直肌径路的变化,可证实4条直肌Pulley的存在并确定其功能位置。 相似文献
10.
We compared the Acrysoft monofocal intraocular lens (IOL) in the mini monovision formula (n = 20) with the Array multifocal intraocular lens (n = 20) for glasses independence after cataract surgery. The Acrysoft monofocal IOL group showed similar and even slightly
better results than the Array multifocal IOL group. The monofocal Acrysoft IOL using the mini monovision (blended vision)
formula is a good alternative for providing post-cataract surgery glasses independence.
Drs. Chen, Clinical Assistant Professor of Ophthalmology and Neal H. Atebara are at University of Hawaii School of Medicine,
Honolulu, Hawaii, USA.
Dr. Te Tsaw Chen, Past Professor & Director, was at Department of Ophthalmology, Taipei Medical University, Taipei, ROC.
The authors have stated that they do not have a significant financial interest or other relationship with any product manufacturer
or provider of services discussed in this article. The authors also do not discuss the use of off-label products, which includes
unlabeled, unapproved, or investigative products or devices.
The authors compared the Acrysoft monofocal intraocular lens in the mini monovision formula to the Array multifocal intraocular
lens for glasses independence after cataract surgery. 相似文献