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81.
目的:探讨小儿恶性淋巴瘤早期诊断的临床线索,争取早期治疗。方法:回顾性分析22例小儿恶性淋巴瘤的临床表现、发病特点和病理检查结果。结果:发病至明确诊断时间平均82天。发病和入院检查有不规则发热、贫血、出血、淋巴结肿大、肝脾肿大。有的甚至有腹痛、下肢疼痛。经病理证实,非霍奇金淋巴瘤19例,霍奇金淋巴瘤3例。结论:小儿恶性淋巴瘤临床早期诊断较困难。主要根据临床表现和体征,再进一步作淋巴结活检和影像学检查。  相似文献   
82.
目的 :探讨 (Dubin Johnsonsyndrome ,DJS)的诊断和鉴别方法。 方法 :对北京医科大学第三医院 196 0~1998年确诊的 10例DJS进行回顾性分析及文献复习。结果 :DJS以慢性持续或间歇性黄疸为主要特征 ,血清胆红素一般轻度升高且以结合胆红素为主 ,ALT及AST正常 ;但并发病毒性肝炎或其它肝病时可升高。口服胆囊造影不显影 ;BSP试验呈典型双峰曲线 ,该方法已被淘汰。腹腔镜下肝脏呈特征性“黑肝”改变 ;肝活检细胞内有棕色或棕黄色色素颗粒沉着。结论 :腹腔镜检查和 /或肝活检是DJS诊断和鉴别诊断的重要方法。  相似文献   
83.
鼻腔、咽部非霍奇金氏淋巴瘤   总被引:2,自引:0,他引:2  
目的 :探讨鼻腔、咽部非霍奇金氏淋巴瘤 ( NHL)的临床特征、诊断要点及误诊原因。方法 :对1 986年~ 1 996年住院的 2 4例鼻腔、咽部非霍奇金氏淋巴瘤的患者作一回顾性分析。结果 :2 4例临床表现差异较大 ,缺乏特征性的表现。首次诊断 NHL6例 ,其余 1 8例初诊时诊断 :慢性鼻炎 8例 ,恶性肉芽肿3例 ,鼻息肉 2例 ,鼻中隔粘膜肥厚 2例 ,扁桃体炎 2例 ,慢性咽炎 1例。 2 4例均经病理切片及免疫组化确诊。结论 :鼻腔、咽部非霍奇金氏淋巴瘤临床表现复杂 ,缺乏特征性 ,早期易误诊。提高临床医师对本病的认识 ,反复活检及免疫组化等方法有利于本病的确诊。  相似文献   
84.
微矩阵基因芯片筛选喉鳞癌相关基因的研究   总被引:11,自引:1,他引:10  
目的:应用基因微矩阵方法筛选喉鳞癌相关基因。方法:按一步法抽提喉鳞癌和对照喉正常组织的总DNA并纯化mRNA;将4096种人类基因PCR产物用CartesianPixsys7500点样仪按微矩阵排列点样于化学涂层的载玻片上,制成基因芯片;将等量的对照组织和喉鳞癌组织mRNA分别逆转录合成荧光分子掺入的cNDA-链做探针,混合后杂交上述基因芯片,经严格洗片后用ScanArray3000扫描仪扫描芯片  相似文献   
85.
Gastrodia elata is an achlorophyllous and fully mycoheterotrophic orchid which obtains carbon and other nutrients from Armillaria species in its life cycle. Many researchers suggested that plant hormones, as signing molecules, play a central role in the plant–fungi interaction. In the process of Armillaria gallica 012 m cultivation, both exogenous indole-3-acetic acid (IAA) and indole-3-butyric acid (IBA) distinctly stimulated the growth of mycelia in solid media. The differential expression genes (DEGs) of A. gallica 012 m with IAA versus blank control (BK) and IBA versus BK were investigated. The results showed that more than 80% of DEGs of the IAA group were coincident with the DEGs of the IBA group, and more than half of upregulated DEGs and most of the downregulated DEGs of the IAA group coincided with those DEGs of the IBA group. Above research implied that A. gallica 012 m could perceive IAA and IBA, and possess similar responses and signaling pathways to IAA and IBA. The overlapping differential genes of the IAA group and IBA group were analyzed by GO term, and the results showed that several DEGs identified were related to biological processes including positive regulation of the biological process and biological process. The downregulated NmrA-like and FKBP_C genes might be benefit to the growth of mycelia. Those results can explain that exiguous IAA and IBA improved the growth of A. gallica to some extent. We speculate that IAA and IBA are signaling molecules, and regulate the expression of growth-related genes of A. gallica 012 m by the same signaling pathway.  相似文献   
86.
鼻咽癌放疗后局部复发和纤维化的增强CT鉴别诊断价值   总被引:16,自引:0,他引:16  
Yan H  Wang D 《中华肿瘤杂志》1997,19(3):203-205
目的探讨鼻咽癌放疗后出现块影时,CT检查对鉴别肿瘤局部复发和放射性纤维化的价值。方法收集159例经CT检查的鼻咽癌,其中放疗后局部复发(RT)37例,放射性纤维化(RF)54例,以68例未经放疗的鼻咽癌(PT)作对比。使用ELScintsprint2000型CT机,测量放疗后出现的块影平扫和强化的CT值,用统计学的方差分析法处理增强前后的CT值差异。结果RT组平扫CT值为50.40±8.10Hu,增强为73.74±7.37Hu;RF组平扫为48.62±10.15Hu,增强为56.74±8.69Hu;对照组(PT)病变区平扫为48.32±9.20Hu,增强为72.38±7.75Hu。测量表明RT组有明显强化,RT组与RF组强化后CT值差异有非常显著性(P<0.01)。结论鼻咽癌放疗后出现块影时,CT增强扫描可作为鉴别诊断的重要方法。  相似文献   
87.
Tumor specimens of 203 infants with neuroblastomas of different clinical stages — registered in successive multicenter clinical trials of the German Society of Pediatric Oncology — could be examined for N-myc amplification, chromosome 1-ploidy and — structure, CD44 std. expression (in tumor tissue, and also in patients sera).Eightyseven (= 43%) of these infants had a non-localized, disseminated neuroblastoma, mainly involving sympathetic nerve tissue, lymphnodes, liver, skin, bone marrow and bones (46 patients were classified into the 4s group, 41 patients in the true 4 group).If the clinical classification between stage 4 and stage 4swas neglected, then 17 of these infants (= 20%) had N-myc amplification (4—64 copies) with 16 already dead. Seven of 9 examined patients with true stage 4 had chromosome 1p aberrations (with N-myc amplification in 5), and among the dead there were 2 with CD44 negative expression.In another series, serum CD44 std. was measured by ELISA, and the highest (significantly different) Kruskal-Wallis mean rank values (147.8) were found in infants (n = 6) with stage 4s compared to the low mean-rank-value of 71.9 in patients with stage 4 (n = 65). Stage 1—3 patients (n = 42) had values of 99.8—88.6.Thus, infants with disseminated neuroblastomas, showing non-diploidy, normal chromosome 1p structure, non-N-myc amplification and high CD44 std. expression in tumor tissue, and also high CD44 std. values in serum, will have the highest chance of survival due to tumor-non-progression.On the other hand, N-myc amplification in the tumor cells was found to be characteristic for stage 4s neuroblastoma patients with tumor progression (n=6). Therefore, 4s neuroblastoma-patients with N-myc amplified tumors should be aggressively treated like true stage 4 tumor patients!  相似文献   
88.
影像检查在恶性黄疸诊断和鉴别诊断中的价值   总被引:1,自引:0,他引:1  
目的:分析胃肠造影、B超、CT和内镜逆行胰胆管造影(ERCP)在恶性黄疸诊断和鉴别诊断中的作用。方法:对83例恶性黄疸包括胰腺癌、肝外胆管癌和壶腹癌分别进行胃肠造影、B超、CT和ERCP检查,分析四种影像学检查的诊断阳性率和正确率,不同恶性肿瘤的特异性检查方法。结果:B超为安全、简便的检查方法,可作为诊断的首选检查,诊断阳性率为9767%,诊断正确率为6069%,特别对壶腹癌诊断正确率达8182%,接近于CT和ERCP。ERCP对恶性黄疸检查阳性率为9848%,总的诊断正确率为8872%,且假阳性和假阴性均较低,特别对胆总管下段病变如壶腹癌、胰头癌等的定性明显优于CT和B超。CT的诊断阳性率为9259%,正确率为8616%,同时能显示出肿瘤及其周围组织情况。胃肠造影有较高的假阳性和假阴性率,对恶性黄疸检查敏感性较低。结论:B超和CT均为无创伤性检查,可作为恶性黄疸常规检查方法,并可了解肿瘤及其周围组织情况。ERCP可作为B超和CT的进一步检查方法。胃肠造影不能作为恶性黄疸诊断和鉴别诊断的必需检查。  相似文献   
89.
Computerized analysis of lesions in US images of the breast   总被引:1,自引:0,他引:1  
RATIONALE AND OBJECTIVES: Breast sonography is not routinely used to distinguish benign from malignant solid masses because of considerable overlap in their sonographic appearances. The purpose of this study was to investigate the computerized analyses of breast lesions in ultrasonographic (US) images in order to ultimately aid in the task of discriminating between malignant and benign lesions. MATERIALS AND METHODS: Features related to lesion margin, shape, homogeneity (texture), and posterior acoustic attenuation pattern in US images of the breast were extracted and calculated. The study database contained 184 digitized US images from 58 patients with 78 lesions. Benign lesions were confirmed at biopsy or cyst aspiration or with image interpretation alone; malignant lesions were confirmed at biopsy. Performance of the various individual features and output from linear discriminant analysis in distinguishing benign from malignant lesions was studied by using receiver operating characteristic (ROC) analysis. RESULTS: At ROC analysis, the feature characterizing the margin yielded Az values (area under the ROC curve) of 0.85 and 0.75 in distinguishing between benign and malignant lesions for the entire database and for an "equivocal" database, respectively. The equivocal database contained lesions that had been proved to be benign or malignant at cyst aspiration or biopsy. Linear discriminant analysis round-robin runs yielded Az values of 0.94 and 0.87 in distinguishing benign from malignant lesions for the entire database and for the equivocal database, respectively. CONCLUSION: Computerized analysis of US images has the potential to increase the specificity of breast sonography.  相似文献   
90.
本文介绍一种以平面热解石墨电极为工作电极,用于识别人类白血病白细胞的半微分伏安型生物传感器。综合使用作者提出的四个电化学识别指标(氧化峰电位Ep,不同扫描电位下氧化峰电位的差值ΔEp,膜上单位细胞数的氧化峰电流Ip/cels以及氧化扫描与还原扫描相应的出峰情况),实现了对人类正常与异常白细胞、各种临床分型白血病白细胞的识别。  相似文献   
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