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排序方式: 共有6661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.
Alexander C. Egbe Rosalyn Adigun Vidhu Anand Collin P. West Victor M. Montori Hassan M. Murad Emmanuel Akintoye Karim Osman Heidi M. Connolly 《The Canadian journal of cardiology》2019,35(12):1784-1790
BackgroundAlthough there are robust data about the pathophysiology and prognostic implications of left ventricular (LV) systolic dysfunction in patients with acquired heart disease, similar prognostic data about LV systolic dysfunction are sparse in the tetralogy of Fallot (TOF) population. The purpose of this study was to perform a meta-analysis of all studies that assessed the relationship between LV ejection fraction (LVEF) and cardiovascular adverse events (CAEs) defined as death, aborted sudden death, or sustained ventricular tachycardia.MethodsWe used random-effects models to calculate hazard ratios (HRs) and 95% confidence intervals (CIs).ResultsOf the 1,809 citations, 7 studies with 2,854 patients (age 28 ± 4 years) were included. During 5.6 ± 3.4 years' follow-up, there were 82 deaths, 17 aborted sudden cardiac deaths, and 56 sustained ventricular tachycardia events. Overall, CAEs occurred in 5.1% (144 patients). As a continuous variable, LVEF was a predictor of CAE (HR 1.29, 95% CI, 1.09-1.53, P = 0.001) per 5% decrease in LVEF. Similarly, LVEF < 40% was also a predictor of CAE (HR 3.22, 95% CI, 2.16-4.80, P < 0.001).ConclusionsLV systolic dysfunction was an independent predictor of CAE, and we observed a 30% increase in the risk of CAE for every 5% decrease in LVEF, and a 3-fold increase in the risk of CAE in patients with LVEF <40% compared with other patients. These findings underscore the importance of incorporating LV systolic function in clinical risk stratification of patients with TOF and the need to explore new treatment options to address this problem. 相似文献
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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.
Why is the age-standardized incidence of low-trauma fractures rising in many elderly populations? 总被引:4,自引:0,他引:4
Pekka Kannus Seppo Niemi Jari Parkkari Mika Palvanen Ari Heinonen Harri Siev?nen Teppo J?rvinen Karim Khan Markku J?rvinen 《Journal of bone and mineral research》2002,17(8):1363-1367
Low-trauma fractures of elderly people are a major public health burden worldwide, and as the number and mean age of older adults in the population continue to increase, the number of fractures is also likely to increase. Epidemiologically, however, an additional concern is that, for unknown reasons, the age-standardized incidence (average individual risk) of fracture has also risen in many populations during the recent decades. Possible reasons for this rise include a birth cohort effect, deterioration in the average bone strength by time, and increased average risk of (serious) falls. Literature provides evidence that the rise is not due to a birth cohort effect, whereas no study shows whether bone fragility has increased during this relatively short period of time. This osteoporosis hypothesis could, however, be tested if researchers would now repeat the population measurements of bone mass and density that were made in the late 1980s and the 1990s. If such studies proved that women's and men's age-standardized mean values of bone mass and density have declined over time, the osteoporosis hypothesis would receive scientific support. The third explanation is based on the hypothesis that the number and/or severity of falls has risen in elderly populations during the recent decades. Although no study has directly tested this hypothesis, a great deal of indirect epidemiologic evidence supports this contention. For example, the age-standardized incidence of fall-induced severe head injuries, bruises and contusions, and joint distortions and dislocations has increased among elderly people similarly to the low-trauma fractures. The fall hypothesis could also be tested in the coming years because the 1990s saw many research teams reporting age- and sex-specific incidences of falling for elderly populations, and the same could be done now to provide data comparing the current incidence rates of falls with the earlier ones. 相似文献
6.
O. M. Karim A. E. Boothroyd J. H. Wyllie 《Annals of the Royal College of Surgeons of England》1990,72(5):304-308
Anthropometric measurements were performed on 51 normal, supine, barium enema examinations to determine the position of the lower pole of the caecum and the base of the appendix relative to palpable bony landmarks (the anterior superior iliac spine and the symphysis pubis). Four quadrants were defined (iliac, umbilical, inguinal and pelvic) by the intersection of the right lateral line and the interspinous line (the line joining the left and right anterior superior iliac spines). The position of the lower pole of the caecum was iliac in 12%, inguinal in 37%, and pelvic in 51%. The appendix or appendix stump was visualised on 53% of the barium examinations. The position of the appendix was iliac in 15%, umbilical in 15%, inguinal in 11%, and pelvic in 59%. The positions of the lower pole of the caecum and base of the appendix are lower and more medial than previously described. 70% of appendices were found to lie inferior to the interspinous line, contrary to established surgical teaching, which assumes McBurney's point to be the surface landmark for the appendix. 相似文献
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8.
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
9.
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
10.