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51.
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   
52.
The acute effects of protein loading (1.5 g kg-1) on glomerular filtration rate (GFR) and urinary albumin excretion (UAE) were investigated in 23 type-I diabetic patients with no clinical nephropathy, and in 7 healthy subjects (controls). The results were compared with renal morphology data. In controls and in 14 diabetic patients (group 1) GFR increased by 27 and 37%, respectively, corresponding to normal renal reserve, but in 9 patients (group 2) GFR decreased by 20%, indicating the absence of a renal reserve. Microalbuminuria was found in none of the patients in group 1 and in 50% of patients in group 2. Two hours after the load UAE increased in all groups, but the increase was most marked in group 2, despite the fall in GFR. The two groups of patients did not differ with regard to the duration and control of diabetes, but differed markedly in terms of baseline GFR (131 vs. 195 ml min-1, P less than 0.01, in groups 1 and 2, respectively). Renal morphology showed minimal non-specific glomerular injury in group 1, and signs of glomerulosclerosis in group 2. We conclude that the impaired renal response to protein load precedes other subclinical manifestations of diabetic renal injury, and may be useful in the diagnosis of latent diabetic nephropathy.  相似文献   
53.
54.
Twenty patients with AIDS who had intracranial lesions underwent both brain biopsy and cerebro-spinal fluid (CSF) examination to compare histological diagnosis with the polymerase chain reaction (CSF-PCR) for the identification of infectious agents. CSF-PCR was performed for herpes simplex virus, varicella zoster virus, cytomegalovirus (CMV), JC virus (JCV), Epstein-Barr virus (EBV), Toxoplasma gondii and Mycobacterium tuberculosis. A definitive diagnosis was obtained by brain biopsy in 14 patients (2 with astrocytoma, 12 with brain infection). CSF-PCR was positive for EBV DNA in 3 of 3 cases of primary cerebral lymphoma, positive for JCV DNA in 6 of 7 biopsy-proven (and one autopsy-proven) cases of progressive multifocal leukoencephalopathy (PML). CSF-PCR was positive for CMV DNA in one biopsy-proven and one autopsy-proven case of CMV encephalitis (the former also had PML) and positive for M. tuberculosis DNA in one case of tuberculous encephalitis. None of the five toxoplasmic encephalitis cases (one definite, four presumptive) were T. gondii DNA positive. There was close correlation between histology and CSF-PCR for CMV encephalitis, PML and PCL. Antitoxoplasma therapy affected the sensitivity of both histological and CSF-PCR methods. Received: 8 November 1995 Received in revised form: 9 July 1996 Accepted: 19 July 1996  相似文献   
55.
乙型肝炎肝内血管病变免疫组织化学观察   总被引:2,自引:0,他引:2  
目的 研究乙型肝炎(乙肝)肝内血管病变与肝病变的关系。方法 270例肝活检标本取自住院乙肝患者,选择10例大致正常肝组织作对照。石蜡包埋,4μm切片,除依次作HE、弹力、网状及胶原杂色外另用特异性平滑肌肌动蛋白单克隆抗生进行免疫组织化学标记,结果 正常肝组织α-SMA仅在原有的肝内动、静脉及胆管壁表达。乙肝病变较轻组肝组织α-SMA示阳必表达占75%;乙肝病变较重及肝硬变组肝组织α-SMA示强阳性  相似文献   
56.
.A sedation regimen using sequential oral trinepazine, intravenous Pethco (pethidine, chlorpromazine and promethazine) and diazemuls was evaluated in children having native kidney (n = 17) and transplant kidney (n = 17) biopsies. Biopsy was successful in all cases, with no serious side effects. A self-reported scale of memory recall and pain perception showed the optimal time for biopsy to be between 30 and 90 min after the intravenous Pethco. The child’s level of distress was measured by a self-reported scale, a parent-reported scale and an observational scale for doctors and nurses; 45% of children rated themselves highly distressed prior to the procedure, their parents being the best assessors of this distress. Younger children and those undergoing native kidney biopsy had less understanding of the procedure. Children’s worries could be clearly categorised into procedural and outcome issues: those undergoing transplant biopsy were more worried about outcome, whereas those undergoing native kidney biopsy were more worried about the procedure. Received April 3, 1995; received in revised form and accepted April 17, 1996  相似文献   
57.
Many patients present with lateral neck lumps due to benign or malignant conditions, and they may be difficult to differentiate clinically. It is detrimental to perform an open neck biopsy on a patient with a cancer originating from the head and neck region (upper aerodigestive tract or skin) prior to definitive treatment. The biopsy interferes with the assessment and management of the neck, increasing morbidity. It may also decrease curability and perhaps induce fungation. A protocol to avoid the need for an open biopsy, using fine needle aspiration cytology and a thorough examination of the upper aerodigestive tract is recommended. The authors also recommend combined radical radiotherapy and surgery for the patient who has had an open biopsy. A thoughtless biopsy is both needless and harmful.  相似文献   
58.
Summary A retrospective evaluation of the prognostic value of different parameters available in patients affected by glial tumours and submitted to serial stereotactic biopsy is presented. The series investigated includes thirty-three untreated patients with proven brain gliomas submitted to stereotactic biopsy. All patients have been clinically and neuroradiologically monitored for three years. The factors investigated belong either to the preoperative data (clinical history and symptomatology, CT pattern and volume of the lesion) or to histological and biological data obtained after the stereotactic biopsy. The results suggest the need of a multimodal prognostic evaluation in glial tumours and particularly stressed is the accuracy of prognostic indications derived from cell kinetic studies.Presented at the European Congress of Neurosurgery, Barcelona, September 1987.  相似文献   
59.
Summary We report a case of a third ventricular neuroblastoma (neurocytoma) in a 66 year old man. A stereotactic needly biopsy was performed to obtain a tissue diagnosis and was followed by total resection. We elected not to give radiation or chemotherapy and to follow the patient closely with serial CT scans. Presently, 48 months postoperatively, the patient is free of tumor by head CT scan and able to live independently. We reviewed the literature of primary cerebral neuroblastomas/neurocytomas occurring in adults (15 years of age) and found 32 cases. Our patient is the oldest of this group with a mean age of 32 ± 14 years (S.D.). The location of the 33 neoplasms was intraventricular in 17 cases (52%) and intraparenchymal in 16 cases. The male to female ratio was 2: 1. Of the 17 patients having a minimal follow-up period of 5 months (mean 51 months), five developed recurrences after 5 to 144 months (mean 50 months) compared to 12 patients without recurrence after a 6- to 72-month follow-up period (mean 52 months). Recurrences occurred statistically significantly more often in parenchymal neuroblastomas/neurocytomas than in intraventricular tumor locations.  相似文献   
60.
Histological criteria for the diagnosis of reflux esophagitis include basal zone hyperplasia, stromal papillae elongation, and inflammatory infiltrate. However, endoscopic esophageal biopsy specimens may include little or no lamina propria. Intraepithelial T lymphocytes, seen in hematoxylin and eosin-stained sections as cells with irregular nuclear contours (CINC), may have a higher density in children with esophagitis. We evaluated the diagnostic accuracy of a numerical score built up by grading the "classical" parameters and its correlation with CINC density in grasp biopsy specimens obtained from children undergoing esophagogastroduodenoscopy with and without esophagitis. We analyzed esophageal biopsy specimens from 349 children (median age, 5 years) subdivided in 4 groups according to the previous routine histology report: group 1, 144 children with esophagitis; group 2, 65 controls; group 3, 51 children with dubious esophagitis; and group 4, 75 children with esophagitis on endoscopy but a normal histology report. A numerical value was assigned to each parameter; the sum of these values represented the histological score. We also evaluated intraepithelial CINC density (ie, number of CINC per high-power field). We separately analyzed histological sections with and without lamina propria. For both total score and for CINC density, we calculated a cutoff using a receiver operating characteristic curve. Cutoffs of 6 for score and of 4 for CINC density provided the best sensitivity and specificity. Sensitivity of the histological score was better in biopsy specimens containing lamina propria (94%) than in those without lamina propria (4%). Sensitivity of CINC density was satisfactory in both specimens with (78%) and without (75%) lamina propria. Specificity was satisfactory for both parameters. In conclusion, when lamina propria was present in sections of endoscopic esophageal biopsy specimens, histological score provided a better diagnostic accuracy for the diagnosis of esophagitis. However, when no lamina propria was present, as was the case in 67% of our children, CINC density had better sensitivity. In addition, this latter parameter showed esophageal mucosa damage in 34% of previously dubious cases or cases with esophagitis at endoscopy but a previous routine histology report of normal mucosa.  相似文献   
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