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81.
乔振军  黄裕新  王景杰 《医学争鸣》2000,21(10):1233-1233
1 病例报告 女 ,45岁 ,因吞咽困难 16 mo伴发热 15 d,于1999- 0 7- 12入院 .于 16 mo前与人争吵后出现吞咽困难 ,以进食馒头、面条为著 ,剑突下有时出现梗噎感 ,随即呕吐 ,呕出所进食物及粘液 ,情绪波动可诱发症状加重 ,伴食欲减退、返酸 .15 d前无诱因出现不规则发热 ,T38~ 39℃ ,上腹痛加重 ,全身酸困不适 ,乏力、头晕、消瘦 .追问病史 ,患者 5 a前双手、足疼痛麻木 ,尤以受凉、精神刺激后明显 ,手指初发白 ,继而发紫 ,变红 ,且麻木疼痛加重 ,手足小关节渐僵硬、畸形 .曾到多家医院就诊 ,诊断 :“雷诺病、类风湿性关节炎”.2 a前出现…  相似文献   
82.
OBJECTIVE: To study the effects of Buyang huanwu decoction (BHD) on the release of von Willebrand factor(vWF) and the expression of tissue factor(TF) activity induced by tumor necrosis factor alpha (TNF alpha) in cultured bovine aortic endothelial cells (BAECs). METHODS: BAECs from neonatal cox were cultured and 4-8 passages were used. Cells were incubated for 8 hours after addition of different treatments. The supernatant was used to measure vWF and BAECs lysate to determine TF activity. RESULTS: 1. Compared with the control, TNF alpha enhanced the expression of TF activity(12.79 +/- 2.59 vs. 4.69 +/- 0.83, P < 0.01) and the effects were in dose-dependent manner(r = 0.9712, P < 0.01); BHD inhibited the effects of TNF alpha(P < 0.01). 2. Compared with the control, TNF alpha promoted the release of vWF from endothelial cells (13.28 +/- 4.76 vs. 6.42 +/- 2.84, P < 0.01) and BHD inhibited the effect of TNF alpha(P < 0.01). CONCLUSION: BHD can inhibit the expression of TF and the release of vWF induced by TNF alpha.  相似文献   
83.
血管内超声(IVUS)图像是观测血管内部结构的首选影像学手段,基于IVUS图像的内膜和中外膜边界的提取是实现冠脉粥样硬化精准诊断的前提和关键。针对IVUS图像结构复杂、对比度低、边界提取困难等问题,本研究提出一种基于改进TransUnet网络的分割方法。首先,针对IVUS图像边界提取难点,对边血管、血管分叉、导丝伪像、阴影等4种图像结构进行建模,并基于建模结果予以定向数据增强;而后,结合IVUS图像的环状结构分布特点,在TransUnet网络中提出了Polar-bias归纳偏置的策略,并对IVUS图像进行像素级的分类;最后,基于分类结果优化GVF snake模型的外力场,进而提取IVUS图像的内膜和中外膜边界。采用国际标准IVUS图像数据集(两组不同中心频率,共512幅图像)对算法进行评测,引入JMard距离(JM),Hausdorff距离(HD)和面积差异百分比(PAD)等3个评测指标,在数据集A中JM为0.87, HD为0.87, PAD为0.18,数据集B中JM为0.91, HD为0.25, PAD为0.08。实验结果表明,所提出的算法在两组数据集的内膜及中外膜提取问题中的表现均...  相似文献   
84.
This report investigates the sequence specificity requirements for homeodomain structure and DNA binding activity by the design and synthesis of a "minimAl" homeodomain (for minimalist design and alanine scanning mutagenesis) which contains the consensus residues and in which all nonconsensus residues have been replaced with alanine. The murine homeodomain Msx served as the prototype for the minimAl homeodomain, Ala-Msx. We show that Ala-Msx binds to DNA specifically, albeit with lower affinity than Msx. A derivative of the minimAl homeodomain, Ala-Msx(NT), which contains a native rather than an alanine-substituted N-terminal arm, has similar DNA binding affinity as Msx. We show that the native N-terminal arm stabilizes the tertiary structure of the minimAl homeodomain. Although Ala-Msx resembles a molten-globule protein, the structure of Ala-Msx(NT) is similar to Msx. The requirement for an intact N-terminal arm is not unique to the minimAl homeodomain, since the N-terminal arm also promotes high-affinity binding activity and appropriate tertiary structure of Msx. Therefore, the homeodomain "scaffold" consists of consensus residues, which are sufficient for DNA recognition, and nonconsensus residues in the N-terminal arm, which are required for optimal DNA binding affinity and appropriate tertiary structure. MinimAl design provides a powerful strategy to probe homeodomain structure and function. This approach should be of general utility to study the sequence specificity requirements for structure and function of other DNA-binding domains.  相似文献   
85.
SEARCHFORHERPESSIMPLEXVIRUSTYPE2(HSV-2)ANDHUMANPAPILLOMAVIRUS(HPV)INTHENORMALANDABNORMALCERVICALSAMPLESZhangWei;张伟;JinShunqia...  相似文献   
86.
Levels of glutathione in liver and kidney, and other nutrients in plasma were evaluated in male and female ascorbate-requiring osteogenic disorder Shionogi (ODS) rats fed semipurified diets in which the concentrations of ascorbate were gradually decreased from 1965 to 180 mg/kg. Plasma ascorbate levels in ODS rats were unaffected when ascorbate levels in the diet were decreased from 1965 to 768 mg/kg. However, plasma ascorbate levels decreased progressively when levels of ascorbate in the diet were decreased from 527 to 180 mg/kg. Plasma ascorbate levels decreased up to 77% when the dietary ascorbate concentration decreased from 1965 to 180 mg/kg. Ascorbate levels in liver and kidney fell as much as 60-70% when the dietary ascorbate levels were reduced from 1965 to 180 mg/kg. However, the glutathione levels in these tissues were not affected. Plasma retinol and vitamin E levels were not affected by decreasing dietary ascorbate intake. Total cholesterol levels increased significantly in female rats as dietary ascorbate intake declined. Levels of glycated hemoglobin decreased significantly when dietary ascorbate levels decreased from 1965 to 527 mg/kg. This study suggests that levels of vitamin E, retinol and glutathione are not affected by decreased dietary intake of ascorbate under nonscorbutic conditions, whereas elevated ascorbate intake is associated with a decrease in levels of plasma cholesterol in female ODS rats. However, excessive intake of ascorbate may be associated with elevated glycation of hemoglobin. To achieve the maximal health benefit of ascorbate supplementation, further studies are necessary to define optimal ascorbate intakes.  相似文献   
87.
88.
为 23 例喉癌患者行喉大部分切除术,采用下列方法重建喉功能,(1)重建声门关闭功能;(2)重建会厌覆盖功能;(3)保留或重建梨状窝;(4)保护喉上神经和喉返神经;(5)保持宽大的下咽部;(6)切断环咽肌。23 例中21 例获得随访,术后均能发音,术后2~4 周拔除鼻饲管,无误吸及呛咳。5 年生存11 例,生存率 478% 。  相似文献   
89.
目的:探索晚期肺腺癌患者化疗疗效和对化疗的耐受性,化疗后生活质量变化和生存期。材料与方法:回顾分析1992-11~1995-04,经病理确诊为肺腺癌。按UICC分期为Ⅲb、Ⅳ期,Kamofsky评分≥60,连续完成2程以上的以铂类药物为主的联合化疗方案治疗患者。结果:化疗有效率3.1%,化疗后Kamofskv评分不变者43.8%,升高40.6%。下降≥10分15.6%,Ⅲb期中位生存期13月,Ⅳ期10月。结论:全身状况较好无化疗禁忌证的晚期肺腺癌患者,给予适当的联合化疗可使部分患者病情改善,生活质量提高。  相似文献   
90.
研究孕期沙眼衣原体,支原体感染治疗效果与胎儿生长发育的关系。方法应用免疫荧光法对600例孕妇宫颈分泌物行沙眼衣原体,支原体属抗原检测,阳性者对配偶行尿道分泌物检测,孕妇阳性者以口服红霉素治疗,观察治疗过程中,胎儿异常及低休 儿发生比较及与配遇感染的关系。  相似文献   
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