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61.
Superficial adenopathy is the most frequent clinical manifestation of lymphoma, both at initial workup and later when disease recurs. Data obtained by means of physical examination and ultrasonography (US) of the cervicosupraclavicular, axillary, and inguinal regions were compared for 120 patients, 60 at the time of initial staging and 60 during follow-up for a previously treated lymphoma. Twenty-nine in the second group had recurrent disease, as confirmed with histologic examination. For all 120 patients, US revealed clinically impalpable lesions in an average of 10.8% of cases for the cervicosupraclavicular region, 17.9% for the axillary region, and 4.1% for the inguinal region. Eight of the 29 relapses were not detected at physical examination, and three were demonstrated solely with US. These findings emphasize the value of US exploration of the superficial node-bearing regions in patients with lymphoma, during both initial staging and follow-up.  相似文献   
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Objective  The performance of colposcopy provided in a screening study in five African countries was evaluated.
Design  Cross-sectional study.
Setting  Burkina Faso, Congo Brazzaville, Guinea Conakry, Mali and Niger.
Population  Women aged 25–59 years.
Methods  A total of 29 294 women participated in a cervical screening study in the five study sites, and newly trained local doctors performed colposcopy and directed biopsies as indicated. Using meta-analytical tools, four measures of colposcopy performance at different thresholds of colposcopic abnormalities were assessed. Sources of heterogeneity were also assessed.
Main outcome measures  Proportions of women receiving biopsies, adequate biopsies and women diagnosed with cervical intraepithelial neoplasia (CIN).
Results  Among 28 553 women with satisfactory colposcopy, 3101 had a colposcopic diagnosis of probable low-grade or worse lesions and 1128 probable high-grade or worse lesions. Overall, the measures that reached the set standards were proportion of biopsy taken at colposcopy threshold of probable high-grade or worse lesions (95%, 95% CI 90–100%) and proportion of adequate biopsy samples. The set standards were not met for the proportions of women diagnosed with CIN at different colposcopic abnormality thresholds. Detection of CIN2 or worse lesions increased with increasing colposcopic abnormality.
Conclusions  The performance of colposcopy in some of the African sites studied was comparable to that previously observed in other studies. With appropriate training, monitoring, continuing practice and quality assurance, adequate standards of colposcopy can be attained in sub-Saharan Africa.  相似文献   
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In a prospective study of 65 patients with bile duct obstruction, various radiologic modalities were compared for their capability to demonstrate the level and cause of obstruction and to indicate accurately tumor resectability. Ultrasound (US) was performed in 65 patients, computed tomography (CT) in 51, direct cholangiography (DC) in 57, and angiography in 35. The level of obstruction was correctly indicated by US in 95% of patients and by CT in 90%, and the cause was correctly indicated by US in 88%, by CT in 63%, and by DC in 89%. In predicting tumor resectability, US was correct in 71% of patients, compared with 42% for CT, 58% for DC, and 25% for angiography. US therefore appears to be the single most useful modality in the evaluation bile duct obstruction.  相似文献   
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目的:在缝合的基础上局部应用纤维蛋白胶治疗损伤的周围神经,观察纤维蛋白胶对周围神经再生的影响。方法:实验于2005-03/07在大连医科大学中心实验室完成。实验材料:纤维蛋白胶(广州倍绣生物技术有限公司,主要成分:纤维蛋白原50~70mg/支和凝血酶400U/支,从哺乳动物血中提纯,经过灭菌消毒,冻干制成,不含致热源)。实验分组:选择健康SD大鼠48只,按随机数字表法分为两组,每组24只:单纯缝合 纤维蛋白胶组、单纯缝合组。实验方法:大鼠麻醉后,于左大腿后外侧做2cm纵切口,显露坐骨神经。距梨状肌下缘远侧约1.5cm处切断坐骨神经,切除远端1~2mm,采用10-0无创伤线缝合神经外膜,使远近端保留约1~2mm间隙。单纯缝合 纤维蛋白胶组:对称缝合2针,将纤维蛋白胶注入缝合周围在神经对合端生成凝胶环,混合物固化形成再生室。单纯缝合组:单纯外膜缝合。实验评估:①术后连续观察动物行为学:手术侧后肢及足趾的运动情况,有无溃疡形成,足趾、趾甲的溃疡愈合情况,观察展爪反射。②术后8周两组各取4只大鼠行神经电生理检查,检测神经传导速度、潜伏期。③术后2,4,6,8周两组各取2只大鼠行苏木精-伊红染色后光镜下观察神经再生情况。④术后8周两组各取4只大鼠采用LUZEX-F彩色图像分析仪对甲苯胺蓝染色神经组织切片中轴突数目及轴突直径进行分析。⑤术后8周两组各取4只大鼠行醋酸铀枸橼酸铅染色,Phlip-10型透射电镜下观察轴突再生情况。⑥术后8周两组各取4只大鼠行辣根过氧化物酶标记观察脊髓前角运动神经元情况。结果:纳入大鼠48只,均进入结果分析。①术后大鼠行为学观察:术后8周单纯缝合 纤维蛋白胶组大鼠除足趾略见下垂、屈曲现象外,步态基本正常,展爪反射基本正常,下肢活动已接进正常,单纯缝合组下肢活动略差。②神经电生理检查:术后8周单纯缝合 纤维蛋白胶组神经传导速度快于单纯缝合组[分别为(11.13±0.37),(9.26±0.44)m/s],潜伏期短于单纯缝合组[分别为(1.83±0.18),(2.17±0.19)ms],差异有显著性意义(F=27.78,5.53,P<0.05)。③光镜下神经再生情况:单纯缝合 纤维蛋白胶组再生的有髓神经纤维髓鞘较厚、直径较大、数量多、排列规则,再生良好。单纯缝合组再生的有髓神经纤维髓鞘较薄、直径较小、数量少、排列不规则,再生较差。④轴突数目及轴突直径:单纯缝合 纤维蛋白胶组在轴突数目、轴突直径大于单纯缝合组[分别为(2187±107),(1847±96)个/400倍视野;(2.79±0.15),(2.05±0.17)μm],差异有显著性意义(F=80.70,42.92,P<0.05)。⑤透射电镜下轴突再生情况:术后8周单纯缝合 纤维蛋白胶组大鼠再生轴突发育良好,排列有序,轴突直径大小相差小,髓鞘厚薄一致,轴突染色均匀,雪旺细胞核呈卵圆型。单纯缝合组大鼠轴突发育差,排列不规则,髓鞘薄,可见扩张血管,部分区域有出血水肿。⑥辣根过氧化物酶标记观察脊髓前角运动神经元情况:单纯缝合 纤维蛋白胶组在实验侧腰骶段前角可见辣根过氧化物酶标记的大型运动神经元,且数目较多。单纯缝合组标记的数量较少。结论:在修复神经过程中应用纤维蛋白胶,可明显促进损伤的周围神经修复与再生,优于单纯缝合的效果。  相似文献   
69.
We have determined concentrations of adenosine, deoxyadenosine, and deoxyATP (dATP) in cord blood from an infant prenatally diagnosed as ADA deficient. Plasma deoxyadenosine and adenosine were already elevated in cord blood (0.7 and 0.5 microM vs. normal of less than 0.07 microM). Elevation of plasma deoxyadenosine has not previously been documented in these children. Erythrocyte dATP content was also elevated at birth (215 nmol/ml packed erythrocytes vs. normal of 2.9). These elevated concentrations of adenosine, deoxyadenosine, and dATP are similar to those we observed in another older adenosine deaminase-deficient patient and may explain the impaired immune function and lymphopenia seen at birth.  相似文献   
70.
A group of unique Epstein-Barr virus-containing cell lines was derived from the bone marrow of three patients with X-linked agammaglobulinemia. Efforts to obtain cell lines from the peripheral blood of these patients were uniformly unsuccessful. Immunofluorescence analyses as well as biosynthetic studies with [(35)S]methionine indicated unusual patterns of Ig synthesis in many of these bone marrow derived lines. Seven of the lines were of particular interest in that two produced no Ig of any type; two others showed no Ig by fluorescence but small amounts by [(35)S]methionine labeling; one expressed only cytoplasmic μ chains without any evidence of light chain synthesis, and two produced primarily μ chains with only slight amounts of light chains. One of the lines without membrane or cytoplasmic Ig studied in detail grew like a typical lymphoid line and was carried in intermittent culture over a period of 2 yr without Ig expression. One line grew quite differently and resembled the round cell type described previously, which has been obtained from a variety of sources. The cell line with cytoplasmic μ chains and no light-chain expression had the characteristic properties of pre-B cells. Three normal type Ig-producing cell lines also were obtained from the patients. The accumulated evidence obtained in the present study indicates that these unusual cell lines represent normal precursor cells of the B-cell lineage; these grew out in these cases because of the virtual absence of mature B cells that ordinarily overgrow the culture system. However, the possibility that in certain instances they reflect abnormal Ig synthesis characteristic of the disease has not been ruled out.  相似文献   
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