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排序方式: 共有2211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.
Background: Dense deposit disease and atypical hemolytic uremic syndrome are often caused by Complement Factor H (CFH) mutations. This study describes the retinal abnormalities in dense deposit disease and, for the first time, atypical haemolytic uremic syndrome. It also reviews our understanding of drusen pathogenesis and their relevance for glomerular disease. Methods: Six individuals with dense deposit disease and one with atypical haemolytic uremic syndrome were studied from 2 to 40 years after presentation. Five had renal transplants. All four who had genetic testing had CFH mutations. Individuals underwent ophthalmological review and retinal photography, and in some cases, optical coherence tomography, and further tests of retinal function. Results: All subjects with dense deposit disease had impaired night vision and retinal drusen or whitish-yellow deposits. Retinal atrophy, pigmentation, and hemorrhage were common. In late disease, peripheral vision was restricted, central vision was distorted, and there were scotoma from sub-retinal choroidal neovascular membranes and atypical serous retinopathy. Drusen were present but less prominent in the young person with atypical uremic syndrome due to a heterozygous CFH mutation. Conclusions: Drusen are common in forms of C3 glomerulopathy caused by compound heterozygous or heterozygous CFH mutations. They are useful diagnostically but also impair vision. Drusen have an identical composition to glomerular deposits. They are also identical to the drusen of age-related macular degeneration, and may respond to the same treatments. Individuals with a C3 glomerulopathy should be assessed ophthalmologically at diagnosis, and monitored regularly for vision-threatening complications.  相似文献   
3.
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   
4.
Non-operative management of malignant intestinal obstruction   总被引:1,自引:0,他引:1  
Intestinal obstruction is a relatively common clinical problem in patients with advanced cancer, particularly those with colorectal and ovarian tumours. A proportion of patients have a non-malignant cause for their obstruction, but in the remaining patients obstruction will be caused by advanced malignancy itself. In the past, most patients were either managed surgically or by nasogastric intestinal decompression and intravenous hydration. Surgery in patients with advanced cancer is associated with high mortality and morbidity. Effective surgical decompression is difficult. We have managed 24 patients with advanced abdominal malignancy and previous operative or radiological evidence of intestinal obstruction without operation. The technique is only appropriate for patients in whom a solitary or correctable obstructing lesion can be excluded. The patient is encouraged to take free fluid and a diet low in fibre. Intestinal colic is managed with morphine, the dose required being titrated for each individual patient against background pain and colic. Vomiting is controlled by the parenteral administration of antiemetic drugs. To simplify drug administration, morphine and metoclopramide are mixed in the same syringe and infused subcutaneously simultaneously. In our 24 patients the mean survival rate after the onset of complete obstruction was 29.2 days. The mean dose of morphine infused was 9.2 mg/h, and the mean dose of metoclopramide was 6.9 mg/h. The case of an 82-year-old male patient is presented. We commend the technique to surgeons contemplating surgery in these very difficult patients. It is simple, relatively non-invasive and saves the patients the pain, discomfort and complications of unproductive surgery.  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.
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   
7.
Evaluation of an on-line patient exposure meter in neuroradiology   总被引:1,自引:0,他引:1  
  相似文献   
8.
9.
The effect of early visual deprivation on the ability of dark- (DR) and light-reared (LR) rats to learn temporal discriminations involving sounds and lights and to abstract the intersensory correspondence involving duration from initial modality-specific training was examined in this study. While visually inexperienced DR rats were somewhat less successful in acquiring an initial discrimination involving visual events and responding to a rule reversal per se, they were as effective as their visually experienced LR counterparts in demonstrating cross-modal transfer (CMT) to signals in a new modality. The results revealed by the investigation are discussed in terms of the consequences and lack of consequences of the manipulation of early visual experience on the ontogeny of intersensory perceptual development in mammals.  相似文献   
10.
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   
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