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11.
Claus Zimmer Stefanie Märzheuser Stephan Patt Arndt Rolfs Joachim Gottschalk Klaus Weigel George Gosztonyi 《Journal of neurology》1992,239(7):394-400
Summary In the hope of finding a treatable condition, the need for rapid diagnosis in HIV-seropositive patients with brain lesions is apparent. In order to evaluate the efficacy of stereotactic brain biopsy in AIDS patients, we retrospectively studied 25 HIV-infected patients undergoing stereotactic biopsy. Brain lesions were identified with gadolinium-enhanced MRI and/or contrastCT. Brain biopsy was performed using the system of Riechert. From 8 up to 15 small tissue samples from one or two targets were obtained in every patient. The biopsy material was examined cytologically, histologically (including electron microscopy), immunohistochemically and, in part, by animal test and polymerase chain reaction (PCR). A definite diagnosis was achieved in 92%. Diagnosis included primary central nervous system lymphoma (PCNSL) (10), toxoplasmosis (10), progressive multifocal leukoencephalopathy (2) and one case of co-existing toxoplasmosis and cytomegalovirus infection. Two biopsies were non-diagnostic. All PCNSLs showed polymorphic B-cell populations of high malignancy; accurate classification according to the Kiel classification was not possible. In 3 lymphomas Epstein-Barr nuclear antigen (EBNA) 2-mRNA could be detected by PCR and confirmed immunohistochemically by EBNA 2 expression. In 6 cases autopsy confirmed the biopsy diagnosis. Conventional histology was not sufficiently decisive for toxoplasmosis and progressive multifocal leukoencephalopathy, so that immunohistochemistry and animal tests became very important for a final diagnosis. With the help of different morphological and molecular biological techniques stereotactic brain biopsy appears to be an effective method in the diagnosis of HIV-associated brain lesions. In view of the marked radio- and chemosensitivity of PCNSLs it is mandatory to establish an early and accurate histological diagnosis for adequate treatment. 相似文献
12.
急性胰腺炎CT、B超、手术及临床对照研究 总被引:5,自引:0,他引:5
笔者分析了24例急性胰腺炎的CT所见,并同B超、临床化验和剖腹探查结果进行了对照研究。表明:(1)急性胰腺炎的CT诊断优于B超,对胆源性胰腺炎B超对诊断有明确帮助。(2)急性胰腺炎时,CT表现与血淀粉酶浓度不一定成正比。(3)急性胰腺炎可累及门脉系统引起血管并发症。 相似文献
13.
Rajni Rani S. A. Zaheer N. R. Suresh R. Walia S. K. Parida A. Mukherjee Rama Mukherjee G. P. Talwar 《Journal of clinical immunology》1992,12(1):50-55
Leprosy patients undergoing phase II trials in two hospitals of New Delhi, India, were HLA typed to see the association of HLA with differential responsiveness toMycobacterium w vaccine. The vaccine comprises an atypical, nonpathogenic mycobacterium,Mycobacterium w, which has cross-reactive antigens withM. leprae. Multibacillary patients who are lepromin negative are vaccinated at an interval of 3 months. Considerable improvement is evident in the patients in terms of a decline in bacterial indices and histopathological and immunological upgrading. But all the patients do not respond to the vaccine in the same manner; some are slow responders, while others are good responders. HLA-A28 and DQw3 (DQw8+9) were found to be associated with slow responsiveness, while DQw1 and DQw7 were found to be associated with a more rapid responsiveness to theM. w vaccine. However, these associations were not significant afterP correction for the number of antigens tested for each locus except for HLA-DQw3 (DQw8 and DQw9) and DQw7. DQw7, a new defined split of HLA-DQw3, seems to be associated with the responsiveness toM. w vaccine. 相似文献
14.
Masaru Kojima Shigeo Nakamura Yasuo Hosomura Kazuhiko Shimizu Yoshiyuki Kurabayashi Hideaki Itoh Katsue Yoshida Yoshihiro Ohno Akihiro Kaneko Shigeyuki Asano Haruki Wakasa Taizan Suchi Takashi Johshita 《Pathology international》1993,43(1-2):11-17
In order to clarify the histological and immunohistochemical characteristics of suppurative granuloma in abscess-forming granulomatous lymphadenitis (AGL), and the relation between AGL and cat scratch disease (CSD), 36 cases of AGL were studied. The combined results showed that there were two types of suppurative granulomas. The suppurative granulomas histologically revealed small lymphocytes of predominantly T cell phenotype distributed among the epithelioid histiocytes bordering central necrotic areas in the suppurative granulomas. These suppurative granulomas could be further subdivided into two groups, mainly those with and without the intermingling of large transformed cells of B-cell phenotypes: Type B granuloma with large transformed B cells and Type A without large transformed B cells. Both types of granulomas were observed in a varying degree in most cases. According to the predominant type of granulomas, 36 patients with AGL were further classified into two groups: Group I of Type A dominance and Group II of Type B dominance. Warthin-Starry (WS) silver stain positive bacteria, which are said to be a causative agent of CSD, were present in about 50% of both groups. No Brown-Hopps' Gram-positive bacteria, fungus, toxoplasma, Chlamydia or Bacillus Calmette-Guerin antigen were found in any case. Clinically, there was no significant difference between these two groups. On the other hand, the detection of WS-positive bacteria seemed to have some relationship with the duration of disease and the history of exposure to cats, and 70% of AGL cases occurred in autumn without a single concurrent epidemic. 相似文献
15.
Dr. K. Richter H. -J. Löblich J. W. Wyllie 《Virchows Archiv : an international journal of pathology》1978,380(3):261-271
Summary Electron microscopic investigations were performed on samples of human tissue obtained from subjects following fatal decompression sickness, associated with hyperbaric air-therapy. Intra- and extracellular gas bubbles of varying size were identified throughout the entire body. Each bubble was covered by an osmiophilic non-homogeneous coat of cloudy and flocculent material, native to its specific locality. This envelope measured from 30 to 560 Angstroem-units in thickness. Association of this covering with an electrokinetic zonal activity, detected biophysically by Lee and Hairston (1971) is assumed. We consider this surface coat prevents nitrogen from being eliminated via the blood-lung-barrier. 相似文献
16.
Juergen Thiele Bert Hoeppner Rudolf Zankovich Robert Fischer 《Virchows Archiv : an international journal of pathology》1989,415(3):191-202
Summary Histomorphometry was performed on representative trephine biopsies of the bone marrow on admission of 50 patients (21 male, 29 female-age 67 years) with so-called primary osteomyelofibrosis/-sclerosis (OMF) not preceded by any other subtype of chronic myeloproliferative disorders. This study was firstly aimed at testing correlations between histological features (amount of haematopoiesis, cytological aspects of mega-karyocytes, density of reticulin and collagen fibres and degree of osteosclerosis) and laboratory data, as well as spleen size and duration of relevant prediagnostic symptoms. Secondly, we concentrated on a discrimination of OMF patients into two sub-groups according to bone marrow morphology and clinical variables. Statistical evaluation of histomorphometric variables and haematological findings disclosed that there was a progressive fibro-osteosclerotic process in the evolution of disease features. Increase in medullary fibrosis was significantly paralleled by an abnormal or pleomorphic megakaryopoiesis in the bone marrow: there was an increase in irregularity of perimeters for megakaryocytes and naked nuclei combined with smaller sizes of these elements including the nuclei. Additionally, there was a greater number of pycnotic bare nuclei. A number of morphometric features (density of fibres, degree of osteosclerosis, amount of haematopoiesis) were associated with corresponding clinical data (spleen size, length of preclinical history). By consideration of a set of basic histomorphometric variables our co-hort of 50 patients could be divided into an early hyperplastic subtype with no or minimal medullary reticulin and another group with conspicuous fibrotic and osteosclerotic alterations of the bone marrow. It was noticeable that we found no significant correlation between amount of haematopoiesis or marrow cellularity with splenomegaly. This result suggests that splenic haematopoiesis (myeloid metaplasia) may represent an autonomous or neoplastic process and not only compensation for a failing fibro-osteosclerotic bone marrow.Supported by a grant from the Deutsche Forschungsgemeinschaft (DFG-Th 390/1-1) 相似文献
17.
Franz Dienstl Robert Gasser Heribert Rauch Rainer Henn 《Virchows Archiv : an international journal of pathology》1985,407(4):457-464
Summary 50 witnessed sudden cardiac deaths in the age group between 20–50 years have been studied at autopsy. The most remarkable findings were a high percentage of stenosis and arterioisclerosis of the descending branch of the left coronary artery and a large amount of three vessel disease. It is clear that severe stenosis and sclerosis of the coronary arteries are not essentially related to sudden cardiac death, but a high number of vessels with moderate stenoses and sclerosis has been found.The severity of vessel disease has been evaluated by a coronary score, which takes the haemodynamic effects of the injured coronary arteries on the myocardium into account. We also noted that patients below 35 years of age who died of sudden cardiac death showed a very low coronary score. 相似文献
18.
Spontaneous histopathological regression of cancer has been reported. The involvement of the immune system in such regression has been advocated, leading to the theory of immunological surveillance against cancer. A prediction of this theory is that common tumour antigens can be recognized upon repeated exposure by cell-mediated immunity, which leads to tumour regression and the subsequent appearance of tumour antigen-loss variants. However, no direct evidence has been provided in non-viral-induced experimental animal models of primary malignancy or in human primary cancer. This study examined two groups of melanoma patients where histopathological regression of the primary tumour was observed. Many of the 23 patients with multiple (> or =3) primary melanomas showed significant regression of their last melanoma (median 33%, mean 40) compared with matched melanomas from patients with a single primary melanoma (median 0%, mean 12) (p=0.0080), or compared with their first primary melanoma (p=0.0013). Regression was consistent with an 'immunization effect' seen in murine tumour transplantation studies, where inoculation with > or =3 asynchronous tumours induces transplantation rejection on subsequent challenge. A significant decrease in the expression of the melanoma common tumour antigen MART-1 in the last primary tumour from multiple melanoma patients (median 8%, mean 24) versus matched single melanoma patients (median 79%, mean 68) (p=0.0041) and in the last versus first tumour in multiple primary patients was found (p=0.0083). Metastases from 17 patients whose primary skin melanomas had completely regressed (occult primary melanoma) also showed significant MART-1 loss (median 0%, mean 11) compared with matched metastases from patients with non-regressing primary melanoma (median 51%, mean 50) (p=0.0013). MART-1 antigen-loss variants observed in the multiple primary and occult primary patients correlated with the presence of peripheral blood MART-1-specific cytotoxic T lymphocytes (CTLs) (p=0.03). No similar effects were observed with two other melanoma antigens, gp100 and CD63. Thus, in two groups of human melanoma patients, evidence is provided for histopathological tumour regression associated with cancer immune surveillance. 相似文献
19.
目的 研究年轻成人Perthes病的临床表现与MRI表现的相关性。方法 对 12例有或无症状年轻成人Perthes病患者作X线和MRI检查 ,测量CE角、ATD、髋臼商、头颈商、关节内侧间隙和髋臼覆盖率等X线指标 ,以及关节积液、外侧关节囊厚度等MRI表现。统计分析其与临床表现的相关性。结果 MRI检查显示外侧关节囊厚度与愈合后遗的症状有相关性 ,关节积液量有明显的差异趋势 ,但因样本量过少 ,统计学分析无差异 ,各项X线测量指标亦未显示明显的相关性。结论 外侧关节囊厚度与年轻成人Perthes病的临床表现有一定相关性。 相似文献
20.
《The surgeon》2021,19(5):268-278
ObjectiveTo compare clinical and imaging findings between extreme lateral lumbar interbody fusion (XLIF) and posterior fusion (PF) via meta-analysis for the treatment of lumbar degenerative diseases.MethodsEnglish papers reporting clinical and imaging findings for the treatment of lumbar degenerative diseases with XLIF and PF published electronically in the PubMed, Embase, Cochrane Library, and Web of Science databases from January 2006 to August 2019 were retrieved. Two authors independently extracted data and evaluated the quality of the included literature. Meta-analysis of outcome measures was performed using Stata 14 and RevMan 5.3 software.ResultsThis meta-analysis included 744 patients from nine studies, two of which were prospective studies, while the others were retrospective studies. The quality of each study was determined to be high. The meta-analysis showed no significant differences in the operative time, length of hospital stay, clinical effectiveness, and improvement in postoperative global sagittal alignment between two approaches (P > 0.05). However, XLIF was significantly better than PF in reducing intraoperative blood loss and recovery of local sagittal alignment (P < 0.05). Moreover, the high incidence of postoperative complications were detected in XLIF group (P < 0.05).ConclusionsBoth surgical approaches have equally promising clinical effectiveness for the treatment of lumbar degenerative diseases. Although XLIF can reduce intraoperative blood loss and obtain better postoperative local sagittal alignment than PF, the high incidence of postoperative complications should prompt us to consider why XLIF procedure is still being offered to our patients and how we can reduce these complications. In addition, any conclusions should be taken with caution because of the mix of prospective and retrospective studies, and the high heterogeneity and bias. 相似文献