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71.
BACKGROUND: Retroperitoneal lymph node dissection (RPLND) following induction chemotherapy has been considered a critical component in the comprehensive management of advanced non-seminomatous germ cell tumors (NSGCT). The objectives of the present study were to review the clinical outcome of patients who underwent RPLND and to evaluate the probability of necrosis alone, based on some readily available clinical data for these patients. METHODS: Forty-seven consecutive patients with NSGCT were treated with first-line chemotherapy at our institution between January 1993 and September 2002. Twenty-four of these patients, who underwent RPLND with normal values of tumor markers after induction chemotherapy, were included in the study. The cause-specific survival rate was calculated using the Kaplan-Meier method. Various predictive factors for the histology were analyzed using multivariate analysis. RESULTS: The pathological findings at resection were necrosis alone in 62.5% of cases, teratoma in 25.0%, and viable cancer in 12.5%. The cause-specific 3-year survival rate of patients who underwent complete and incomplete resection was 100% and 50.0%, respectively. Among several clinical factors, prechemotherapy tumor size less than 50 mm was found to be an independent predictor of necrosis alone (hazard ratio = 4.45, P= 0.04). CONCLUSION: Metastatic tumor size before chemotherapy appears to be one of the most important factors for the prediction of necrosis alone in the resected specimens of RPLND. The prognosis of patients might be influenced by the degree to which resection has been completed.  相似文献   
72.
Granular cell tumor is a benign neoplasm which frequently occurs in the oral cavity, skin, and subcutaneous tissue. Granular cell tumor of the bladder is an extremely rare disease, and only nine cases have been reported. We present here an additional case of granular cell tumor occurring in the bladder. Unlike the other tumors reported, this tumor extruded into the Retzius' cavity. Therefore, the tumor was successfully excised through extraperitoneal laparoscopic surgery. The patient was free from recurrence 40 months after surgery. The small tumor located in Retzius' cavity could be managed with extraperitoneal laparoscopic surgery.  相似文献   
73.
A female infant with 21 trisomy syndrome associated with congenital chylothorax was reported. She was born at a gestational age of 34 weeks by Cesarean section because of fetal hydrothorax and hydrops fetus, confirmed by ultrasonography at 32 weeks. Emergent resuscitation and immediate thoracentesis were performed soon after birth. After beginning breast feeding, the serous pleural fluid became opalescent and a diagnosis of congenital chylothorax was made. Feeding was changed to medium-chain triglyceride (MCT) feeding and the production of pleural effusion disappeared after thoracentesis was performed several times. Accumulating evidence suggested that MCT feeding and intermittent thoracentesis under echo guide were effective. Some reports on patients, including this one, suggest that there may be more patients with 21 trisomy associated with congenital hydrothorax. Therefore, congenital hydrothorax might be listed as a complication of 21 trisomy.  相似文献   
74.
Four types of materials, type I collagen coat (Coat), acid-soluble type I collagen gel (Hardgel), pepsin-treated acid-soluble type I collagen gel (Softgel), and an extract of extracellular matrix of the murine Engelbreth-Holm-Swarm sarcoma (Matrigel), were used as matrices to culture rat hepatic parenchymal cells, and their morphological changes and adhesion were compared to the matrices by electron microscopic observations. Hepatic parenchymal cells cultured on Coat and Hardgel were extended and flattened, whereas cells cultured on Softgel and Matrigel assembled and formed aggregates. Such aggregates consisted of several hepatic parenchymal cells, with a recognizable bile duct-like alveolus on the inside. Morphologically, the aggregates were more spherical on Matrigel and oval shaped on Softgel. Microvilli of the cell surface were parallel to the matrix on Matrigel, but invaded into the gel on Softgel. Subsequently, investigation into how these morphological features affected the liver-specific functions, including secretion of albumin and induction of P450 by 3-methylcholanthrene, demonstrated that a high level of liver function was maintained in a long-term culture in hepatic parenchymal cells on Softgel. These results suggest that hepatic parenchymal cell interactions were stronger with Softgel than with Matrigel, and that Softgel appears to closely mimic the in vivo environment.  相似文献   
75.
: Maintaining high levels of intracellular cyclic AMP (cAMP) is known to inhibit the growth of various proliferating cells including hepatocytes. We show here that transient (30 min) elevations of cAMP induced by addition of 8-bromo-cAMP (1 mmol/L) to rat hepatocytes in primary culture at three time points (12h, 16h and 20h) after seeding stimulated DNA synthesis. Sustained levels of cAMP stimulated DNA synthesis to a lesser degree at a lower concentration (1 μmol/L), but inhibited it at concentrations higher than 100μmol/L. We also determined cyclin-dependent kinase 2 (cdk2) activity in the hepatocytes during this incubation period. The transient addition of 8-bromo-cAMP at the late G1 phase increased cdk2 activity. This suggests that transient cAMP elevation in hepatocytes at the late G1 phase has a growth stimulation effect. Up-regulation of cdk2 activity may have a role in this process.  相似文献   
76.
Effects of glycyrrhizin on immune-mediated cytotoxicity   总被引:10,自引:0,他引:10  
Intravenous administration of glycyrrhizin is known to decrease elevated plasma transaminase levels in patients with chronic viral hepatitis, in which immune-mediated cytotoxicity by cytotoxic T lymphocytes and tumour necrosis factor (TNF)-α is considered to play an important pathogenic role. However, the immunological interpretation of the transaminase-lowering action of glycyrrhizin is not known. Studies were performed to elucidate this action immunologically by assessing the effects of glycyrrhizin on immune-mediated cytotoxicity using an antigen-specific murine CD4+ T hybridoma line, which exhibits cytotoxicity against antigen-presenting cells after stimulation with specific antigen, and a murine TNF-α-sensitive fibroblast line. Glycyrrhizin inhibited the cytotoxic activity of the T cells against antigen-presenting cells and also suppressed TNF-α-induced cytotoxicity in the TNF-α-sensitive cell line in vitro. These results suggest that the decrease of elevated transaminase levels by glycyrrhizin in patients with chronic viral hepatitis is mediated in part by inhibition of immune-mediated cytotoxicity against hepatocytes.  相似文献   
77.
78.
MATERNAL HYPERTHYROIDISM AND CONGENITAL MALFORMATION IN THE OFFSPRING   总被引:1,自引:0,他引:1  
Six hundred and forty-three neonates from mothers with Graves' disease were examined for major malformations of external organs to compare the influence of maternal hyperthyroidism vs. ingestion of methimazole (MMI) during the first trimester on the incidence of congenital malformations. The subjects were divided into four groups according to maternal therapy and thyroid status during the first trimester as follows: (1) infants whose mothers did not receive MMI and were hyperthyroid (Group 1), (2) infants whose mothers did not receive MMI and were euthyroid (Group 2), (3) infants whose mothers received MMI and were hyperthyroid (Group 3) and (4) infants whose mothers received MMI and were euthyroid (Group 4). The prevalence of malformed infants in these four groups was 6.0% (three of 50), 0.3% (one of 350), 1.7% (two of 117) and 0.0% (none of 126), respectively. The incidence in Group 1 was significantly higher than that in Group 2 (P less than 0.01). There was no discernible dose dependency of MMI on the occurrence of malformations. These findings suggest that maternal uncontrolled hyperthyroidism may cause congenital malformations and that the beneficial role of MMI treatment outweighs its teratogenic effect, if any.  相似文献   
79.
Two autopsy cases of Cronkhite-Canada syndrome were reported. The caused of hypoproteinemia, electrolyte imbalance and ectodermal changes were discussed with reference to previously reported cases. The mechanism of protein loss was probably due to outflow into the intestinal lumen of the mucous substance in the cystically dilated glands, directly and/or indirectly followed by loss of mucosal surface. Electrolyte imbalance probably developed from gastrointestinal loss as well as poor substitution. The ectodermal changes were probably not a subsequent part of the emaciation or hypoproteinemis, but an inherent part of this disease. Therapy, whether substitution or surgical procedure, should be selected in order to control the general condition of the patient.  相似文献   
80.
The isolation and characterization of β-lipotropin from fin whale (Balaenoptera physalus) pituitary glands are described. The proposed primary structure is also presented. Fin whale β-LPH exhibited an identical lipolytic activity when compared with human hormone.  相似文献   
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