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81.
The core sequence of the enhancer of murine leukemia virus (MuLV) long terminal repeat is highly conserved in a large number of MuLV strains and appears to play an essential role when SL3-3 or Moloney strains induce T cell lymphoma in mice. We found by using the electrophoretic mobility shift assay that a polyomavirus enhancer core-binding protein, PEBP2, bound to this core motif of MuLV. We also noted that PEBP2 in several hematopoietic cell lines derived from B lymphocyte, macrophage and myelocyte lineages migrated significantly faster than the authentic PEBP2 detected in NIH3T3 (ibroblasts. Interestingly, PEBP2 detected in the cell lines of T lymphocyte lineage appeared to contain both types, which were indistinguishable in electrophoretic mobility from those of NIH3T3 and of B lymphocyte, macrophage and myelocyte lineages. The treatment of the nuclear extract containing PEBP2 with phosphatase generated PEBP3, which is a subcomponent of PEBP2 and retained the same DNA-binding specificity as PEBP2. The altered mobility of hematopoietic cell-derived or T lymphocyte-derived PEBP2 was found to be due to the alteration of the mobility of PEBP3. Based on the distinct mobility of PEBP2/3 of T lymphocytes from those of other hematopoietic cells, we discuss the implication of PEBP2 in MuLV-induced T cell leukemia and T cell-specific gene expression.  相似文献   
82.
T-cell infiltration was detected by immunohistochemistry in only 2 of 10 sural nerve biopsies from patients with Guillain-Barré syndrome (GBS). The number of endoneurial macrophages, identified by the monoclonal antibody MAC 387, was increased, compared with the number in 10 cases of axonal neuropathy. Macrophage-associated demyelination was identified in 7 and axonal degeneration in 8 cases. Cytomegalovirus (CMV) genome was not detected with the polymerase chain reaction.  相似文献   
83.
Summary Sarcoidosis is a multisystem disease characterized by enhanced immune responses at sites of involvement. To elucidate the immunopathogenesis of ophthalmic lesions, cell infiltrates in biopsies from conjunctiva and other tissues involved (lungs, lymph nodes, skin) were studied in 26 patients with active sarcoidosis in order to define the surface phenotype and the distribution of cells in granulomatous lesions. Biopsy specimens were also stained for detection of immunoglobulins, complement and fibrinogen deposits. The data demonstrate a lymphocytes/macrophages interaction in the central core of granulomatous areas as the crucial event that initiates the maintains the state of inflammation: at all sites of disease activity is present a compartmentalization of T-cells expressing a helper-related phenotype which account for the great majority of infiltrating cells both in the early lesions (aggregate of macrophages surrounded by lymphocytic infiltrate) and in well-organized sarcoid granulomata. The presence of plasma cells and immunoglobulin deposits may represent an epiphenomenon in line with the helper infiltration, suggesting a local hyper-reactivity of the B-cells immune system. This study suggests some immunopathogenetic mechanisms leading to the formation and growth of conjunctival sarcoid granulomata.  相似文献   
84.
In order to assess the suitability of DNA flow cytometry of fine-needle aspirates for quantiftring spermatogenesis, the results from DNA flow cytometry were compared to histological evaluation of testicular biopsies taken concomitantly from 171 previously maldescended testes. In 137 of 171 cases, sufficient material for flow cytometric as well as histological evaluation was obtained.
Histological analysis of surgical biopsy specimens revealed spermatogenesis including the spermatid stage in 117 of the 137 gonads. In six of the 117 gonads no haploid cells were found using flow cytometry. On the other hand, surgical biopsies failed to reveal spermatogenesis in five cases in which the corresponding aspirates contained haploid cells. Both methods therefore seem equally sensitive in detection of spermatogenesis.
Other types of histological patterns also corresponded to distinct DNA histograms.
Thus, in 11 of 12 cases with Sertoli-cell-only pattern in all tubules, at least 95% of the cells had a diploid DNA content. Furthermore, predominance of tubules with maturation arrest at the primary spermatocyte level corresponded to an increased proportion of tetraploid cells.
When compared to surgical biopsy, DNA flow cytometry of testiclar fine-needle aspirates is a more objective, easy and rapid method, which is more convenient for the patient. This study has indicatedthat DNA flow cytometry is a suitable method of quantitative assessment of spermatogenesis. One of the first target groups might be men with azoospermia. In such men, DNA flow cytometric analysis of fine-needle aspirates and surgical biopsy are apparently of equal sensitivity in detecting gonads with spermatogenesis. We conclude that DNA flow cytometry may become an alternative method for the quantification of spermatogenesis.  相似文献   
85.
Objective: To determine whether the quality of infiltrations in chest radiographs can accurately predict the histological extent of fibrotic change in patients with acute respiratory distress syndrome (ARDS). Design: Retrospective clinical investigation. Setting: Intensive care unit (ICU) of a university teaching hospital. Patients and methods: Of 47 patients treated with extracorporeal membrane oxygenation (ECMO) for severe ARDS over a 5-year period, 23 patients underwent open lung biopsy at thoracotomy for treatment, mostly of pneumothorax. Chest films obtained by portable chest roentgenography preceding the operation were reviewed retrospectively and compared to the histomorphological results of the lung specimen. Results: Chest radiographs displayed mixed alveolar-reticular opacification in 60.2 %, alveolar patterns in 22.9 % and reticular opacities in 10.5 %. In 0.4 % there were no infiltrates, 6 % could not be evaluated because of insufficient quality. There was no relevant difference between the right and left lungs. Subdividing patients into two groups according to the histological results of either absent or mild (1) or severe (2) lung fibrosis, we found an alveolar haziness in 12.3 % in group 1 compared with 28.2 % in group 2, while reticular characteristics were identified in 13 % and 11 %, respectively. Conclusions: The most common opacity in chest radiographs of patients with severe ARDS treated with ECMO is mixed alveolar-reticular opacification. Severe lung fibrosis is not positively correlated with a reticular radiographic pattern. ECMO does not lead to specific radiological changes in conventional radiograms, contrary to clinical findings that treatment with ECMO might induce pleural or pulmonic haemorrhage, especially in the earlier days when systemic heparinization had to be used instead of the heparin-coated tube-surfacing. Received: 24 November 1997 Accepted: 20 July 1998  相似文献   
86.
The so-called “widenings of the myelin lamellae” are thought to be specific ultrastructural features of peripheral nerve myelin in patients with peripheral neuropathy associated with a monoclonal dysglobulinemia of IgM type and antiglycolipid activity. We report here a case of Guillain–Barré syndrome with no evidence of serum monoclonal dysglobulinemia, presenting the typical widenings of the myelin lamellae in small-diameter myelinated fibers from a sural nerve biopsy. In view of the positive reaction with anti-C3d complement on direct immunofluorescence, an immunological mechanism may be involved in the widenings of the myelin lamellae. © 1994 John Wiley & Sons, Inc.  相似文献   
87.
16例胸膜间皮瘤临床分析   总被引:2,自引:0,他引:2  
16例胸膜间皮瘤,其中1例有石棉接触史,占6.17%;>40岁者占81.5%。主要临床表现为胸痛、气短、咳嗽、低热和胸腔积液,临床上易误诊为结核性胸膜炎、肺癌胸膜转移等。胸部x线检查及胸部CT对该病的诊断有帮助,大都有特征性表现。确诊靠针刺胸膜活检及开胸活检。胸膜间皮瘤的治疗主要采用手术、放疗和化疗,对于局限型治疗首选手术切除。肿瘤的良、恶性、疾病的分期及治疗与预后有一定关系。  相似文献   
88.
Kimura's disease is a rare disorder that involves regional lymph nodes and the major salivary glands, which become infiltrated by eosinophils and lymphocytes. Renal lesions associated with Kimura's disease are rare. We describe the case of a 60-year-old Japanese woman who first noted a nodular mass in a salivary gland. As the nodule grew, nephrotic syndrome and heart failure developed. A biopsy of the nodule revealed Kimura's disease, and surgical excision was performed. After the operation, the heart failure and nephrotic syndrome, which were diagnosed as minimal change disease on renal biopsy, improved rapidly without steroid therapy. Four months later, the nephrotic syndrome recurred without recurrence of Kimura's disease. The patient showed marked improvement during prednisolone therapy (40 mg/d) and was in complete remission 4 weeks after the initiation of steroid therapy. This case shows that surgical excision and prednisolone therapy are useful for nephrotic syndrome associated with Kimura's disease.  相似文献   
89.
对病理学确诊的25例病毒性心肌炎(VMC)和10例扩张型心肌病(DCM)患者心内膜心肌活检标本,运用ABC技术,进行了免疫球蛋白IgG、IgM、IgA和补体C3的检测。结果:20例VMC和9例DCM的标本中,发现了IgG和IgM的沉积,主要分布于心肌肌膜和毛细血管内皮,IgG的肌膜沉积与同步做的病理切片中观察到的心肌细胞坏死和炎性细胞浸润有病理形态学联系。两组患者中均未发现IgA和C3沉积。结果显示,IgG是参与VMC和DCM心肌损伤的主要免疫球蛋白,心肌病变与抗体诱导的免疫反应有关。  相似文献   
90.
The role of open lung biopsy (OLB) in the diagnosis of the etiology of lung infiltrates in children was analyzed for a 10-year period 1979-1989 in a tertiary referral center. A total of 18 children had 19 lung biopsies to ascertain the cause of lung infiltrates. Thirteen of these children (72 %) were immunocompromised due to treatment of hematological/solid malignancies and bone marrow transplantation. The clinical diagnosis was bilateral lung infiltrates of unknown etiology in 17 of 18 children. Eight of these children were ventilated for respiratory failure. The biopsy was useful in achieving a histological diagnosis in 18 of 19 samples (diagnostic yield 95%) and an etiological diagnosis in 14 of 19 samples (etiological yield 74 %). Therapeutic strategy was altered in 14 of 18 patients based on the biopsy results. Five of 14 patients responded favorably to a change in specific treatment. The lime interval from onset of respiratory illness to biopsy was 2-60 days (mean 16 days). Despite the critical state of these children there were few complications associated with the biopsy and no mortality directly related to the procedure. We recommend that OLE be undertaken sooner rather than later in immunocompromised children with bilateral pulmonary infiltrates of unknown etiology.  相似文献   
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