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31.
目的 分析儿童急性白血病伴侵袭性肺部真菌感染(IPFI)的临床特点、真菌分布及影响因素。方法 回顾性分析2018年1月—2022年12月安徽省儿童医院82例急性白血病患儿的临床资料,按照是否合并IPFI分为IPFI组(18例)和非IPFI组(64例)。比较两组患儿的一般临床资料;采用多因素一般Logistic回归模型分析儿童急性白血病伴IPFI的危险因素;分析IPFI组患儿的临床特征、真菌菌种分布。结果 18例IPFI患儿均有不同程度的发热,体温>38.5℃占比72.22%,咳嗽咳痰/白色黏痰占比83.33%;18例IPFI患儿中5例表现为结节实变影,7例表现为多发斑片状阴影,8例表现为散在斑片状阴影合并小结节,2例表现多发云雾状毛玻璃样高密度影、间质病变为主。16例获得真菌微生物学证据,血培养2例,肺泡灌洗液涂片1例,血或者肺泡灌洗液NGS检测13例,其中以毛霉菌(31.25%)、曲霉菌(25.00%)、近平滑假丝酵母菌(18.75%)为主;多因素一般Logistic回归分析结果显示,化疗方案含激素■、中性粒细胞缺乏时间≥10 d[■]、抗菌药物使用种类≥2种■均是儿童急性白血...  相似文献   
32.
Summary At clinical presentation, the majority of malignant tumors are composed of multiple clonal subpopulations of tumor cells with different phenotypic characteristics. Using the experimental tumor model ER 15-P, a methylcholanthrene-induced pleomorphic sarcoma of the C57 Bl6J mouse, we studied a system of long-term in vivo passages of this primary tumor for cell morphological changes, and alterations in the potential for spontaneous lung metastases. Transplants from the primary after the 4th, 20th, 40th and 80th i.m. passage (referred to as T4, T20, T40, and T80 respectively) together with their lung metastases were investigated by light microscopy, immunohistochemistry, and electron microscopy. In addition, the potential for metastasis to the lungs in each group was determined and compared with that of the parent T4 tumors. T4 tumors were mainly composed of spindle-shaped tumor cells with the ultrastructural features of fibroblasts and myofibroblasts, often arranged in a storiform or fasciculated growth pattern, and intermingled with tumor giant cells. Some small areas contained polygonal or rounded tumor cells, ultrastructurally undifferentiated, and sometimes arranged in a hemangiopericytoma-like growth pattern. Although electron-microscopical findings clearly demonstrated the mesenchymal origin of these tumor cells, immunostaining with a polyclonal antibody to vimentin was unspecific in all tumor cells and normal mouse tissue. Monoclonal antibodies to vimentin from different sources were completely negative in tumor cells and murine stromal components. In contrast, myofibroblast-like tumor cells showed immunohistochemically, a moderate to strong co-expression with monoclonal antibodies to desmin, muscle actin and -smooth muscle actin. On the basis of these morphological findings, the primary ER 15-P was classified as a pleomorphic myofibrosarcoma. The lung metastases of T4 tumors were mainly composed of undifferentiated round to polygonal tumor cells, while the number of desmin-positive, muscle- and -smooth muscle-actin-positive cells was reduced. The morphological features of T20 tumors and their lung metastases were the same as in T4, indicating a relative stability of the phenotype up to that stage. In contrast, T40 and T80 tumors and their lung metastases were found to contain almost exclusively undifferentiated tumor cells and many tumor giant cells. While fibroblast-like tumor cells were seen only occasionally, myofibroblast-like tumor cells had almost completely disappeared. The potential for lung metastases was nearly constant in all groups, suggesting metastatic stability. Obviously, the undifferentiated tumor cells of this model are associated with a higher metastatic potential.Abbreviations T4, T20, T40, T80 transplants from the primary tumor after the 4th, 20th etc. i.m. passage - MFH malignant fibrous histiocytoma  相似文献   
33.
513例住院精神分裂症患者临床特点的性别差异   总被引:5,自引:0,他引:5  
目的 :比较男性及女性精神分裂症住院病人的起病年龄、症状特点、病程演变特点及社会功能等指标的差异。方法 :选择 5 13例住院精神分裂症患者 ,详细收集临床资料 ,并进行《阳性及阴性症状评定量表》 (PANSS)及《大体功能量表》 (GAF)的评定 ,以此为依据进行性别间的比较分析。结果 :(1)总体上看 ,男性患者的起病年龄 (2 5 6± 7 3岁 )显著早于女性患者 (2 7 5± 8 6yrs) (P <0 0 1) ,但有家族史的患者间起病年龄差异不显著 (2 6 3± 6 9岁vs 2 6 8± 8 4岁 ) ;与男性相比 ,女性患者具有如下倾向 :症状模式较多为持续阳性症状 ,多为发作性波动或轻度恶化病程 ,阳性及情感症状更明显 ,且未婚或离婚的比例(5 3 9% )显著低于男性 (67 2 % )。结论 :男性及女性精神分裂症患者在发病年龄、症状特点及病程转归等多方面均存在显著差异 ,提示在制定治疗康复方案方面 ,应有所区别  相似文献   
34.
Intending to clarify the true Incidence of Invasive lobular carcinoma of the breast In Japanese women as well as the frequency of unilateral multlcentriclty, 362 cases of clinically defined monocentrlc breast cancer without pre-operative biopsy (previously fine needle aspiration or needle biopsy were routinely carried out for every case) were examined by whole mammary gland serial sectioning. On the basis of pathology and the World Health Organization classification of breast tumors, each case was assigned to one of two main histologlc types: Invasive lobular carcinoma (ILC) or Invasive ductal carcinoma (IDC). Invasive lobular carcinoma was further separated into classic and variant types by employing previously published criteria. Twenty-one cases of ILC (5.8%) were diagnosed, which Is more than In most previous Japanese studies. Unilateral multicentric breast carcinoma was detected In 9.5% of ILC and 16.1% of IDC (the difference was found not significant). Microscopically, ILC tumors were found to be, on average, larger than IDC. Patients with classic type ILC tended to be younger than those with variant type or IDC. Estrogen receptor expression was found more frequently In variant type ILC than in classic type. These results suggest that the incidence of invasive lobular carcinoma of the breast In Japanese women is low and that unilateral multicentricity Is not significantly higher in ILC than in IDC.  相似文献   
35.
随着多层螺旋CT扫描速度和Z轴分辨率的提高,CT在显示血管的解剖与疾病方面得到很大发展,因此,CTA诊断血管疾病起着越来越重要的作用。本文着重介绍多层螺旋CT及CTA诊断主动脉病变的研究进展。  相似文献   
36.
 We have been using the Gyro centrifugal pump C1E3 for cardiopulmonary bypass in anticipation of high efficiency, low hemolysis, and antithrombogenicity of this pump. However, the clinical evaluation of this pump remains to be clarified, because it has been a short time since the pump appeared in clinical situations. The aim of the present study is to inspect and analyze the Gyro pumps morphologically after clinical use. We examined 80 consecutive pumps after cardiopulmonary bypass for 186 ± 67 min with a mean flow rate of 2.52 ± 0.22 l/min/m2 at a mean rotational speed of 2485 ± 81.1 rpm. Although no abnormal findings were present in 79 pumps, one pump was found to contain effusion at the connection between the impeller body and the shaft. The extudate was supposed to be blood, based upon the results of X-ray spectrometer analysis. The cause was determined to be the upward deviation of the shaft off the impeller body. Scanning electron microscopy showed scratches on a part of the bottom housing and a smooth surface of both the male and female pivots of the pump. Surface profile measurement revealed that the deformity of the female pivots was 0.14 mm (top) and 0.05 mm (bottom). These observations suggest that the floating force and vibration by the rotating impeller acted on the joint zone between the alumina ceramic shaft and the polycarbonate impeller body, resulting in dissection of the adhesive agent from the polycarbonate. Although this abnormality may be rare, the structural design still may need to be improved. Received: November 9, 2001 / Accepted: February 4, 2002  相似文献   
37.
We carried out an experiment to analyze morphological differences in hearts of rats well adapted and poorly adapted to chronic hypoxia. Male and female Wistar rats, 1 week, 4 weeks and 9 weeks old, were employed on the assumption that adaptive ability was dependent on age and sex. These rats were raised at an altitude of 2,400 m and were kept for 7 to 9 weeks. Control groups were maintained at an altitude of 600 m during the same period of time. Each group consisted of 4 to 6 rats. At the end of the experiment, body weight, heart weight, ratio of heart weight to body weight and hematocrit were measured, and ventricular wall thickness, myocardial fiber diameter, capillary supply and mitochondria were morphometrically studied. Of the 6 experimental groups, the 4-week-old male rats (M2) had the highest body weight, as compared with the other experimental groups. In addition, relative to these other experimental groups, the following features were found for M2. Heart weight was intermediate, heart weight/body weight ratio was low and hematocrit was also low. Ventricular wall thickness was intermediate in the right ventricle (RV) and interventricular septum (IVS) but was thin in the left ventricle (LV). Myocardial fiber diameter was intermediate in the RV, large in the IVS and small in the LV. Capillary supply was intermediate in the RV and dense in the IVS and LV. Mitochondria were small but cristal density and percentage area, estimated from electron micrographs, were found to be high. These data showed that in well developed rats under chronic hypoxia, there is good development of capillary supply with corresponding restriction of cardiac hypertrophy, while hematocrit count and mitochondria are also affected.  相似文献   
38.
Summary A 37-year-old man with severe transfusion-requiring anemia and neutropenia associated with lymphocytosis of large granular lymphocytes (LGLs) has been followed over a period of 3.5 years. Detailed phenotyping of the LGL has been performed, revealing a phenotype of CD3+, CD8+, CD16+, HLA-DR+, and Leu-7+. Southern-blot analysis of the T-cell receptor beta-chain locus detected a gene rearrangement, thus providing proof of monoclonality of the peripheral blood LGLs.Abbreviations CD Cluster of differentiation - LGLs Large granular lymphocytes - PBMCs Peripheral blood mononuclear cells  相似文献   
39.
An unusual case study of a desmoplastic small round cell tumor presenting as a 3.5-cm, firm, supraclavicular neck mass and diagnosed by fine-needle aspirate biopsy in a 16-yr-old male is reported. Clinical, cytologic, and immunocytochemical findings are described. Histologic, immunohistochemical, and genetic features are discussed. Desmoplastic small round cell tumor should be considered in the differential diagnosis of small round cell tumors of any site; the importance of ancillary studies in arriving at the correct diagnosis is emphasized.  相似文献   
40.
包埋前免疫电镜双标技术在神经解剖学研究中的应用   总被引:2,自引:0,他引:2  
李金莲 《解剖学报》2002,33(5):524-529
目的 在超微结构水平观察两种神经递质在纤维终末内的共存或一种神经递质与其相应受体之间的关系。 方法 包埋前免疫电镜双重标记技术———酶标法和免疫金 银标记法相结合的方法。 结果 在免疫反应双重标记的纹状体切片上 ,电镜下观察到大量的SP样 (过氧化物酶免疫反应产物 )阳性终末和SP受体 (SPR ,免疫金 银标记颗粒 )样阳性神经元的胞体和树突 ,同时可见部分SP样阳性轴突终末分别与SPR样阳性神经元的胞体或树突形成对称性轴 体或轴 树突触联系。而在三叉神经脊束核尾侧亚核切片上 ,电镜下可观察到大量的两种囊泡膜谷氨酸转运体 ,即DNPI样 (过氧化物酶免疫反应产物 )和VGluT1样 (免疫金 银标记颗粒 )阳性轴突终末 ,同时还观察到DNPI样和VGluT1样双标的轴突终末与阴性树突形成非对称性突触。 结论 包埋前免疫电镜双重标记技术敏感性较高 ,组织的抗原性保存好 ,特别是在神经解剖学研究中 ,用于研究两种神经递质在同一个细胞或终末内的共存或分析神经递质与其相应受体之间的联系中有独到之处。  相似文献   
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