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91.
The CA 125 tumour-associated antigen: a review of the literature   总被引:11,自引:1,他引:11  
CA 125 is an antigenic determinant on a high-molecular-weight glycoprotein recognized by a monoclonal antibody which was raised using an ovarian cancer cell line as an immunogen. During the last 5 years the studies reviewed in this paper have provided information concerning the nature, distribution and clinical significance of CA 125. The CA 125 determinant is expressed by epithelial ovarian tumours and various other pathological and normal tissues of Müllerian origin. The function of the glycoprotein expressing CA 125 remains unclear but the distribution of the antigen suggests that it may have a physiological role. The highest serum levels of CA 125 are found in ovarian cancer patients, but elevation of serum CA 125 may also be associated with other malignancies and benign and physiological states, including pregnancy, endometriosis and menstruation. Despite limitations of sensitivity and specificity serum CA 125 estimation is of clinical value in the pre-operative diagnosis and monitoring of ovarian malignancy and may be a prognostic indicator for this disease. The role of CA 125 in screening for early-stage ovarian cancer is currently under investigation. Recent reports suggest that serum CA 125 measurement may also be of value as a prognostic indicator in endometrial cancer and as a reflection of disease status in advanced endometriosis.  相似文献   
92.
Cyclin B3 has been conserved during higher eukaryote evolution as evidenced by its identification in chicken, nematodes, and insects. We demonstrate that Cyclin B3 is present in addition to Cyclins A and B in mitotically proliferating cells and not detectable in endoreduplicating tissues of Drosophila embryos. Cyclin B3 is coimmunoprecipitated with Cdk1(Cdc2) but not with Cdk2(Cdc2c). It is degraded abruptly during mitosis like Cyclins A and B. In contrast to these latter cyclins, which accumulate predominantly in the cytoplasm during interphase, Cyclin B3 is a nuclear protein. Genetic analyses indicate functional redundancies. Double and triple mutant analyses demonstrate that Cyclins A, B, and B3 cooperate to regulate mitosis, but surprisingly single mutants reveal that neither Cyclin B3 nor Cyclin B is required for mitosis. However, both are required for female fertility and Cyclin B also for male fertility.  相似文献   
93.
To determine whether donated blood samples in African countries could be pooled, then tested for the presence of human immunodeficiency virus (HIV) antibodies with a single test without loss of accuracy, a single test on five pooled samples was used, followed by individual testing of positive pools. This resulted in no loss of either sensitivity or specificity. Pooling 10 samples resulted in a loss of sensitivity for low antibody titre specimens. Pooling reduced the costs of screening by 70% and time needed for analysis. It is concluded that pooling of five samples for HIV screening may result in a substantial reduction in costs; in countries where the prevalence of HIV is higher than the 2-3% found in Zimbabwean donors, however, savings may not be as great.  相似文献   
94.
Chlamydial pneumonitis induced in newborn guinea pigs.   总被引:1,自引:0,他引:1       下载免费PDF全文
One- to three-day-old guinea pigs were inoculated intranasally with the chlamydial agent of guinea pig inclusion conjunctivitis. Physical signs of infection included a marked increase in respiration rate on days 5 to 10 of infection and radiographic evidence of pneumonia on day 6. When animals were killed at various times after infection and lung tissue was examined by histopathology, evidence of pneumonia was found beginning on day 4 and lasting as long as day 12, with maximal pathological changes on days 6 to 8. The pneumonia was generally unilateral and consisted of an acute inflammatory component in the bronchioles with granulocytes in both the lumen and the wall of the bronchioles and an interstitial and intra-alveolar mononuclear infiltrate in the parenchyma of the lung. Chlamydial antigen was detected in the bronchial epithelial cells by immunoperoxidase staining, and the guinea pig inclusion conjunctivitis organism was isolated from lung tissue on days 6 to 9. No other significant bacteria were isolated from lung tissue or seen on gram stains of lung sections. Both immunoglobulin M and immunoglobulin G serum antibodies to the guinea pig inclusion conjunctivitis agent were detected as early as day 8 and reached peak levels on day 12. The infection was apparently self-limiting. This model presents the opportunity to investigate pathophysiological and immunological aspects of chlamydial respiratory infections in a neonatal animal.  相似文献   
95.
BACKGROUND: The etiology of IgA nephropathy (IgAN), the most common form of glomerulonephritis in the world, remains an enigma. Episodes of nephritis are frequently preceded by acute viral respiratory syndromes, but few experimental models associated with acute viral infection exist. EXPERIMENTAL DESIGN: An animal model of IgAN involving Sendai virus, a rodent parainfluenza virus similar to many human respiratory viruses, is described. Mice were either naturally infected or chronically mucosally immunized with virus. Immunized mice were then challenged intravenously with various physical forms of antigen to simulate viremia or antigenemia secondary to acute viral exposure. Twenty-four hours after challenge of immunized mice or 10 days after natural infection, mice were sacrificed. Anti-viral antibody titers, glomerular immune deposits, and glomerular function were evaluated. RESULTS: Chronic mucosal immunization of mice with Sendai virus resulted in a vigorous serum IgA (and IgG) anti-viral immune response, associated with comparable degrees of IgA, IgG, IgM, and antigen deposits in the glomeruli of both challenged and unchallenged mice. Only immunized, challenged mice developed significant proteinuria and hematuria. Neither deposits nor glomerular dysfunction was seen in controls. The physical form of antigen was important for altered glomerular function; although immunized mice challenged with either live or dead virions had a high incidence of hematuria, mice challenged with purified viral glycoproteins did not, even though all mice exhibited comparable immune deposits. Significant deposits of C3 were not present and were not required for glomerular injury. Finally, naturally infected mice exhibited a milder form of IgAN without hematuria. CONCLUSIONS: The experimental conditions for acute exposure to a natural viral respiratory pathogen of mice leading to IgAN are described. This model may be useful both to probe infection-related IgAN, and to facilitate the understanding of the various mechanisms responsible for IgAN.  相似文献   
96.
The potential for the use of the disk diffusion method to accurately predict penicillin MICs for Streptococcus pneumoniae was investigated with penicillin (6 μg), methicillin (5 μg), and oxacillin (1 μg) disks. A total of 183 S. pneumoniae isolates were tested by three MIC procedures (agar dilution, microdilution, and E-test). Regression analyses of the geometric mean of the three MIC results against (i) the sum of the zone diameters for methicillin, penicillin, and oxacillin disks; (ii) the sum of the zone diameters for methicillin and penicillin disks; and (iii) each of the three individual zone diameters were performed. Calculated MICs were determined from each of these regression analyses and compared to the mean reference MICs. A high level of correlation was obtained with both the two- and the three-disk procedures (r = 0.97), with essential agreement rates (±1 doubling dilution) between MICs calculated by the three-disk procedure and the two-disk procedure and the mean reference MICs of 98.4 and 98.9%, respectively. No major or very major errors were obtained with the two- or three-disk procedures. The accuracy of the disks used individually was lower (r = 0.84 to 0.93). However, oxacillin and methicillin disk testing remain excellent for screening strains, with all penicillin-susceptible strains having zones of >21 and >22 mm, respectively. The combination disk procedure, which involves the use of three disks (methicillin, oxacillin, and penicillin) or two disks (methicillin and penicillin) for testing S. pneumoniae, can provide accurate penicillin MICs and qualitative category results that are comparable to results obtained by the E-test, agar, and microdilution MIC methods.  相似文献   
97.
Summary 42 patients with advanced stage III and IV squamous cell carcinoma of the head and neck were treated with initial cisplatin and bleomycin chemotherapy and subsequent radiotherapy. 39 were evaluable for results, and 3 for toxicity only. 8 patients suffered from stage III and 31 from stage IV tumors, of these 10 with distant metastases. 5 patients underwent later a rescue operation. 27 were previously untreated (= group A) including 2 cases with localized relapses beyond the margins of surgical and/or radiotherapeutic treatment fields. 12 patients had a recurrence within pretreated areas (= group B). The induction chemotherapy alone showed the following results: In group A 4 (15%) CR, 10 (37%) PR, 7 (26%) MR; in group B 3 (25%) PR, 2 (17%) MR. The subsequent radiotherapy mostly consisted of a 65 Gy tumor dose given in 61/2 weeks. The results after completion of the combined modality therapy were: In group A 44% CR, 28% PR; in group B 10% CR and 30% PR. No patient resistant to the initial chemotherapy responded to the radiotherapy. The median survival time of stage III patients was 20 months but only 7 months in stage IV patients. 4 of all live with NED now between 30+ and 41+ months; 1 patient is alive with relapse. All the others are dead after a survival time of max. 32 months, included the 5 with rescue operation. In general, hematologic and renal toxicities were not severe, but nausea and vomiting were the worst tolerated side effects. 1 patient died from septic myocarditis having a WBC nadir of 2000/µl, probably due to additional immunologic deficiency because of inactive liver cirrhosis. The poor results concerning NED survival are discussed. We conclude, that an initial chemotherapy with CDDP and BLM gives good remission effects but its combination with radiotherapy at present fails to produce a NED survival benefit. Further efforts are necessary to improve the CR and the long time survivor rates.
Die Autoren danken folgenden Kollegen für ihre Mitarbeit: Drs. Garbea (HNO), B. Bienko, M. Danker, N. Birke, M. Klessing, K. Lottner, W. Palm  相似文献   
98.
A case of monomicrobial endocarditis due toPrevotella bivia in a 60-year-old man without previous cardiac lesions is reported. The extremely indolent course with multiple systemic emboli as the only clinical manifestation occurring at least seven months before diagnosis and the persistently negative blood cultures were remarkable features of this case. The incidence, clinical characteristics, treatment and outcome of published cases of infective endocarditis due to anaerobic bacteria are briefly reviewed.  相似文献   
99.
100.
Summary Some patients with hereditary nephritis (HN) who have received a renal transplant have been shown to form antibody with specificity for the NC1 domain of collagen type IV, a major constituent of glomerular basement membranes (GBM). We attempted to duplicate this phenomenon in a family of dogs with X-linked HN, a model for human X-linked HN, by immunizing affected male dogs with normal dog NC1 domain. A collagenase digest was prepared from normal dog GBM, the NC1 domain was separated into dimer (50 kDa) and monomer (24 kDa and 26 kDa) components by SDS-PAGE, and injected into two affected male dogs. Antisera obtained from both dogs contained antibody which reacted with the NC1 domain of dog and human GBM by a plate-binding radioimmunoassay, bound to the dimer and 26 kDa monomer bands by Western blotting, and staining dog and human GBM by immunofluorescence (IF). The affected male dog antiserum reacted equally by radioimmunoassay with the NC1 domain isolated from GBM of unaffected, affected male, and carrier female dogs in the family with X-linked HN, and bound by Western blotting to dimers and the 26 kDa monomer band of the NC1 domain of GBM in each group of dogs. However, the affected male dog antiserum differentiated these dogs by IF; it produced global staining of GBM of unaffected dogs, failed to stain GBM of affected male dogs, and produced segmental staining of GBM of carrier female dogs. Absorption of the affected male dog antiserum with normal dog NC1 domain eliminated the staining of dog GBM by IF, whereas staining persisted after absorption with affected male dog NC1 domain. The abnormal staining patterns of GBM seen by IF in the affected male and carrier female dogs and the results of the absorption studies imply an abnormality of one or more determinants in the 26 kDa monomer band of the NC1 domain of their GBM. Amino acid sequencing of this band identified the 1(IV) chain of collagen type IV, a finding that has implications for the pathogenesis of canine X-linked HN. Absent and segmental staining respectively were also seen by IF in GBM of a male and female patient with HN, using the affected male dog antiserum. Thus, the results obtained in affected male and carrier female dogs with X-linked HN may also be relevant to patients with this disease.  相似文献   
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