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991.
目的:明确多发性基底细胞癌的皮肤镜特点。方法:回顾性分析行皮肤镜检查并经组织病理确诊为基底细胞癌的7例多发性基底细胞癌患者的25处皮损。结果:皮损表现为散在血管模式20处,无血管模式5处;蓝灰色卵圆巢21处,多发性蓝灰色点及小球16处,不典型血管15处,无结构区13处,色素减退12处,线性毛细血管扩张11处,出血/溃疡11处,枫叶状结构10处,螺旋状血管10处,分支状血管7处,乳红色小球7处,红白背景下无结构区7处,逗号样血管5处,乳红色小点4处,轮幅样结构2处。结论:多发性基底细胞癌皮肤镜常见表现为散在血管模式,蓝灰色卵圆巢及多发性蓝灰色点及小球。 相似文献
992.
993.
994.
Brain abscess and necrotic brain tumor: discrimination with proton MR spectroscopy and diffusion-weighted imaging 总被引:15,自引:0,他引:15
Lai PH Ho JT Chen WL Hsu SS Wang JS Pan HB Yang CF 《AJNR. American journal of neuroradiology》2002,23(8):1369-1377
BACKGROUND AND PURPOSE: Discriminating pyogenic brain abscesses from cystic or necrotic tumors is sometimes difficult with CT or MR imaging. We compared findings of proton MR spectroscopy ((1)H-MRS) with those of diffusion-weighted imaging to determine which technique was more effective for this differential diagnosis. METHODS: Fourteen patients (necrotic or cystic tumor [n = 7]; pyogenic abscess [n = 7]) who underwent 1.5-T (1)H-MRS and diffusion-weighted imaging and had findings of ring-shaped enhancement after contrast agent administration were enrolled in this study. Diffusion-weighted imaging was performed with a single-shot spin-echo echo-planar pulse sequence (b = 1000 s/mm(2)). The apparent diffusion coefficient and ratio were also measured. RESULTS: Spectra for two patients were unacceptable because of either poor shimming conditions or contamination from neighboring fat. Spectra in three of five patients with abscess had lactate, amino acids (including valine, alanine, and leucine), and acetate peaks; one of the three spectra had an additional peak of succinate. In one patient with abscess treated by antibiotics, only lactate and lipid peaks were detected. Spectra for four of seven patients with cystic or necrotic tumors showed only lactate peaks. Lactate and lipids were found in three patients with tumors. Hyperintensity was seen in all the pyogenic abscess cavities and hypointensity in all the cystic and necrotic tumors on diffusion-weighted images. CONCLUSION: (1)H-MRS and diffusion-weighted imaging are useful for differentiating brain abscess from brain tumor, but the latter requires less time and is more accurate than is (1)H-MRS. (1)H-MRS is probably more limited in cases of smaller peripheral lesions, skull base lesions, and treated abscesses. 相似文献
995.
996.
Short‐term MyD88 inhibition ameliorates cardiac graft rejection and promotes donor‐specific hyporesponsiveness of skin grafts in mice
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Wen‐Tao He Li‐Min Zhang Chao Li Shu‐Yuan Li Zuo‐Chuan Ding Ze‐Min Fang Fan‐Ying Meng Zhonghua Klaus Chen Ping Zhou 《Transplant international》2016,29(8):941-952
Recognition of evolutionarily conserved ligands by Toll‐like receptors (TLRs) triggers signaling cascades in innate immune cells to amplify adaptive immune responses. Nearly all TLRs require MyD88 to transduce downstream signaling. MyD88 deficiency has been shown to promote the allograft acceptance in mice. However, direct evidence for therapeutic potential of MyD88 inhibitors remains lacking. Herein, we used a MyD88 inhibitor, namely ST2825, to explore its therapeutic potential and mechanisms in fully allogeneic skin and heart transplant models. Phenotypic maturation of dendritic cells stimulated by TLR ligands was alleviated by ST2825 in parallel with reduced T‐cell proliferation in vitro. A short‐course treatment with ST2825 significantly prolonged cardiac graft survival (mean survival time = 18.5 ± 0.92 days vs. 7.25 ± 0.46 days). ST2825‐treated group had significantly reduced proinflammatory cytokines in allografts compared with control group. ST2825 combined with anti‐CD154 induced long‐term skin allograft acceptance in about one‐third of recipients (>100 days). ‘Skin‐tolerant’ recipients showed attenuated donor‐specific IFN‐γ responses, intact IL‐4 responses, and compromised alloantibody responses. We conclude that MyD88 inhibitor ST2825 attenuates acute cardiac rejection and promotes donor‐specific hyporesponsiveness in stringent skin transplant models. The direct evidence suggests that pharmacological inhibition of MyD88 hold promising potential for transplant rejection. 相似文献
997.
Wang M Jin Q Tu H Mao Y Yu J Chen Y Shou Z He Q Wu J Zheng S Chen J 《International urology and nephrology》2011,43(4):1009-1017
This study aimed to diagnose renal allograft dysfunction with specific biomarkers by serum proteomic analysis. Surface-enhanced laser desorption/ionization time-of-flight mass spectrometry (SELDI-TOF MS) and bioinformatics (support vector machine and leave-one cross validation) were used to analyze serum proteome. Enrolled patients included 38 biopsy-proved acute rejection (BPAR), 10 acute tubular necrosis (ATN), 24 subclinical rejection (SCR) and 29 stable control recipients verified by protocol biopsy. A characteristic protein profile can be detected in each renal allograft dysfunction group. BPAR patients were differentiated from stable patients with markers of 9710.1, 4971, 6675.5, 8563.8, 6709.2, 9319 and 4476.7 Da with high sensitivity and specificity. ATN can be clearly distinguished from BPAR and stable control. Subclinical rejection differentiated from stable control with markers of 9193.1, 2759.1, 8464.6 Da. The independent blind test yielded with high specificity and sensitivity for each group. Serum proteome analysis by SELDI-TOF MS combined with bioinformatics in renal allograft dysfunction is valuable and promising. Specific markers were detected in each group. Identification of these proteins may prove useful as diagnostic markers for allograft dysfunction and better to elucidate the mechanism of acute rejection. 相似文献
998.
目的观察雷洛昔芬和苯甲酸雌二醇对植入裸鼠的人乳腺组织雌激素硫酸转移酶(EST)表达的影响。方法15例正常乳腺组织植入75只裸鼠。每例标本分5份,分别植入5只裸鼠后分为5组:对照(Ⅰ组)、苯甲酸雌二醇1mg/kg(Ⅱ组)及雷洛昔芬0.3mg/kg(Ⅲ组)、3mg/kg(Ⅳ组)、30mg/kg(Ⅴ组)。给药30d后取出移植的乳腺组织,采用逆转录聚合酶链反应(RT—PCR)方法检测ESTmRNA的表达。结果与Ⅰ组相比,Ⅱ组EST mRNA表达升高;半定量EST mRNA约为对照组的2倍(P〈0.05)。Ⅲ、Ⅳ、Ⅴ三组ESTmRNA表达与Ⅰ相比无显著性差异(P〉0.05)。结论剂量1mg/kg的雌激素上调EST表达,雷洛昔芬对正常乳腺的EST表达无影响。 相似文献
999.
背景:中央脊髓综合征是常见的不完全性颈脊髓损伤,目前关于其手术与非手术处理的利与弊仍是脊柱外科争论的焦点。目的:探讨中央脊髓综合征的手术治疗效果及预后。方法:回顾性分析2009年1月至2012年6月采用手术治疗的34例中央脊髓综合征患者的临床资料,男24例,女10例;年龄39~76岁,平均53.6岁;前路手术26例,后路手术8例。采用日本骨科协会(JOA)评分标准对患者神经功能进行评定,记录所有患者术前、术后6个月及末次随访的JOA评分,评估手术疗效并分析其预后情况。结果:34例患者全部获得随访,随访时间为6~23个月,平均(14.5±3.8)个月。术前JOA评分平均为(8.8±1.8)分,术后6个月提高至(13.9±2.1)分,末次随访为(14.6±1.5)分。术后6个月及末次随访时的评分改善率分别为(66.1±21.6)%和(73.6±15.2)%。术后1例发生脑脊液漏,1例发生硬膜外血肿,无一例发生椎动脉损伤、切口感染、内固定物失败等并发症。结论:手术解除椎管内的压迫是治疗中央脊髓综合征的有效方法。对于诊断明确的中央脊髓综合征,在全身情况允许的条件下,宜早期根据椎管内脊髓损伤的节段、压迫来源及程度等选择相应的手术方案,以改善脊髓内血供,减少脊髓继发性损害,促进神经功能的改善和恢复。 相似文献
1000.
目的 探讨胆管癌组织中凋亡基因Fas、FasL的蛋白表达及其与胆管癌的发生、发展及预后判断的关系.方法 :应用免疫组化S-P法检测22例胆管癌组织及10例先天性胆管囊肿组织中Fas、FasL的表达.结果 :胆管癌Fas蛋白表达率为45.45%(10/22),显著低于对照组90%(9/10)(P<0.05);而FasL蛋白表达率为72.73%(16/22),显著高于对照组(P<0.05).淋巴结或远处转移的患者中Fas表达率明显下降(P<0.05);FasL阳性表达主要集中在TNM分期Ⅲ~Ⅳ期、有淋巴结或远处转移的患者中(P<0.05).Fas、FasL表达无显著相关性.FasL阳性而Fas阴性的患者累积生存率高于其他患者(P<0.05).结论 :胆管癌细胞中存在Fas表达下调而FasL表达上调现象,并与临床分期及是否转移密切相关.Fas、FasL基因异常表达是反映胆管癌恶性行为及判断预后的有用指标. 相似文献