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991.
Liver-derived lymphocytes were isolated from 40 human livers with end-stage liver disease that were removed at the time of orthotopic liver transplantation. In addition, 10 resection specimens or whole livers removed from patients with liver cancer and seven normal livers (unused donor organs) were studied as controls. Liver-derived lymphocytes were isolated from enzymatically digested tissue by gradient centrifugation and adherence to plastic. Their phenotypical characteristics were studied by two-color flow cytometry, and effector cell function was determined in 4-hr 51Cr-release assays against a natural killer-sensitive target, K562 (natural killer activity), natural killer-resistant Daudi line (lymphokine-activated killer activity) and by P815 line with or without phytohemagglutinin to assess lectin-dependent cellular cytotoxicity. Liver-derived lymphocytes isolated from normal liver contained equal proportions of T and natural killer lymphocytes (mean natural killer/T ratio = 0.7). CD3-CD56+CD16- natural killer cells were the main natural killer subset present in liver-derived lymphocytes, in contrast to the predominant natural killer phenotype in the circulation (CD56+CD16+). Control liver-derived lymphocytes had levels of cytotoxicity significantly greater than those of the normal peripheral-blood lymphocytes against all three targets. In contrast, liver-derived lymphocytes isolated from organs with advanced liver disease differed markedly in the natural killer/T cell ratio and levels of liver-derived lymphocyte cytotoxicity. Liver-derived lymphocytes obtained from hepatocellular carcinoma or rejecting allografts treated by immunosuppressive therapy had virtually no cytotoxicity.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
992.
So-called mesothelioma of the atrioventricular node is a rare lesion and a cause of sudden, unexpected death. A case of congenital complete heart block accompanied by polyclonal immunoblastosis is presented. The histological features of our case are fundamentally similar to that of the cases previously reported. Immunohistochemical findings indicated that the tumor may have originated from aberrant epithelial or mesothelial tissue.  相似文献   
993.
We report a rare case of simultaneous bilateral testicular germ cell tumors arising from uncorrected cryptorchid testes. Each side had a different histological type, which consisted of pure high grade seminoma on the left side, and teratocarcinoma with choriocarcinoma and yolk sac tumor elements in addition to seminoma on the right side. Patients with cryptorchidism are known to have a higher risk of germ cell tumors. Genetic factors also may have a role in the oncogenesis in our patient, since his older brother had had a seminoma in the left cryptorchid testis previously. Both patients had the HLA-Aw24 antigen. The characteristics of familial testicular tumors are discussed.  相似文献   
994.
In order to investigate the behavioral characteristics of the SART-stressed (repeated cold-stressed) animal, a model of dysautonomia, step-down passive avoidance performance was examined in SART-stressed mice. SART-stressed mice exhibited a shortened test trial latency and a decreased incidence of maximum latency of 300 sec, but no change in the training latency. These alterations were blocked by single administration of chlorpromazine or carpipramine prior to the training trial. Repeated, but not single treatments with neurotropin and hopantenate improved the impaired performance due to SART stress. On the other hand, alprazolam and diazepam were ineffective by either mode of administration. Thus, SART-stressed mice appear to have impairment in the process of acquisition of a passive avoidance task.  相似文献   
995.
996.
The systemic distribution of 14C-labeled formaldehyde which had been placed in the root canals of the canines of cats following pulpectomies was studied using liquid scintillation counting and wholebody autoradiographic technique. Radioactive 14C which had been placed in the canals was found in the plasma 30 min after the root canal procedure. The recovery of systemic 14C radioactivity increased with time. In addition, it seemed that approximately 3% of the dose placed in the teeth was excreted in the urine within 36 h. Whole-body autoradiograms indicated extensive concentration of 14C radioactivity in tissues other than those analyzed with the liquid scintillation technique.  相似文献   
997.
998.
Clinical significance of CA19-9 for endometriosis   总被引:1,自引:0,他引:1  
We investigated the usefulness of measuring the serum CA19-9 concentration in the diagnosis and therapeutic monitoring of endometriosis, and compared it with the serum CA125 concentration. We added an immunohistochemical study on CA19-9 and CA125 to find their localization in the various lesions of endometriosis. 1. The positive rate of serum CA19-9 in patients with endometriosis is 52.0% and that of CA125 is 48.0%. When both markers are examined, their positive rate increases to 71.4%. 2. As the Beecham classification stage advanced, the serum CA19-9 positive rate tended to increase. 3. The patients with endometriosis were followed up after surgery or during Danazol therapy. CA19-9 correlated closely with the clinical course. 4. The immunohistochemistry of CA19-9 shows that it localizes in chocolate cysts, but not in the lesions of adenomyosis. CA125 is seen in both lesions. The localizing of CA19-9 is thus seen to be different from that of CA125. It is concluded that the measurement of the serum CA19-9 concentration combined with that of CA125 is useful in the diagnosis and therapeutic monitoring of endometriosis.  相似文献   
999.
1000.
PURPOSE: To investigate the relationship between diabetic macular edema and the levels of vascular endothelial growth factor (VEGF) and interleukin-6 (IL-6) in aqueous humor and plasma.DESIGN: Comparative cross-sectional study. METHODS: Fifty-four eyes from 54 diabetic patients were used. The concentrations of VEGF and IL-6 in undiluted aqueous specimens (obtained from the eyes during cataract surgery) and in plasma were measured by an enzyme-linked immunosorbent assay. To assess blood-aqueous barrier function, the aqueous flare intensity was measured by a laser flare-cell meter as an estimate of the aqueous protein level. RESULTS: The aqueous levels of VEGF and IL-6 were significantly correlated with the severity of macular edema (rho = 0.628, P <.001 and rho = 0.517, P <.01, respectively), as well as with the aqueous protein concentration (rho = 0.618, P <.001 and rho = 0.588, P <.001, respectively). Aqueous levels of VEGF and IL-6 were significantly higher than their respective plasma levels (both P <.001). In addition, the aqueous level of VEGF was significantly correlated with that of IL-6 (rho = 0.537, P <.01). Furthermore, the status of the posterior vitreous significantly correlated with the severity of macular edema (rho = 0.618, P <.0001). CONCLUSIONS: These results suggest that both VEGF and IL-6 are produced together in the intraocular tissues, and are involved in the pathogenesis of macular edema.  相似文献   
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