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991.
Various novel recombinant human tumor necrosis factor-α (TNF) mutants were prepared using protein engineering techniques, and their cytotoxic activity was compared with that of the intact form of TNF (intact TNF). Mutant 471 (a TNF mutant molecule with the deletion of 7 amino acids at the amino-terminal and the substitution of Pro8Ser9Asp10 by ArgLysArg) had a 6-fold higher cytotoxic activity against murine L929 cells. The mutant TNF had an increased ability to bind to TNF receptor on murine L929 fibroblasts cells. A cross-linking study revealed that mutant 471 had an increased ability to form an active trimer. Mutant 471 also showed higher cytotoxic activity against human KYM myosarcoma cells and human MIA PaCa-2 pancreatic carcinoma cells. The possible cachectin activity of the mutant was almost the same as that of intact TNF. These results suggest that mutant 471 might be a more promising candidate as an anticancer agent than intact TNF.  相似文献   
992.
Allelic Frequency of p53 Gene Codon 72 Polymorphism in Urologic Cancers   总被引:2,自引:0,他引:2  
Alterations in the p53 tumor suppressor gene appear to be important in the development of many human tumors. The wild-type p53 gene has a polymorphism at codon 72 that presents the arginine (CGC) or proline (CCC) genotype, which recently has been reported to be associated with genetically determined susceptibility to smoking-related lung cancers. To determine whether this p53 genotype influences individual risk of urologic cancer and/or its progression, we used polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) analysis to assay the allelic frequencies of this polymorphism in 85 renal cell carcinoma patients, 151 urothelial cancer patients, 33 testicular cancer patients, 28 prostatic cancer patients and 56 patients without neoplastic disease. The allelic distributions of the three genotypes (Arg/Arg, Arg/Pro, Pro/Pro) in patients with renal cell carcinoma (29.4%, 55.3%, 15.3%), urothelial cancers (45.7%, 39.7%, 14.6%), testicular cancer (45.4%, 48.5%, 6.1%) or prostate cancer (42,9%, 50.0%, 7.1%) did not differ significantly from those in the normal controls. However, Pro/Pro genotype in renal cell carcinoma and urothelial cancer (smoking-related cancers) was more frequent than that in prostate cancer and testicular cancer (smoking-unrelated cancers) with borderline significance (P=0.0881). There was no particular correlation between frequency of the three genotypes and grade or stage of each type of tumor. The association of genetic predisposition to urologic cancers with p53 gene codon 72 polymorphism is not so clear as the previous study of Japanese lung cancer patients, but this polymorphism may play some role in urothelial cancers and renal cell carcinoma, in which smoking is an epidemiological risk factor.  相似文献   
993.
The clinical importance of microvessel quantitation as a prognostic indicator in invasive breast cancer was examined. This study included 155 patients with invasive breast cancer, with a median follow-up of 82 months. Microvessels were identified by immunohistochemical staining for factor VIII-related antigen in formalin-fixed, paraffin-embedded primary tumours. For each tumour, microvessels were counted within a 200 x magnification field in the area of highest microvessel density. Microvessel counts (MVCs) had no correlation with tumour size, lymph node status or histological grade. When patients were classified by MVC, higher counts were associated with shorter disease-free survival and overall survival (P < 0.025 and P < 0.01 respectively). Multivariate analysis showed that MCV is an independent prognostic factor. Microvessel quantitation may be a useful predictor for identifying breast cancer patients at high risk for relapse and death.  相似文献   
994.
Cellular localization of amylase in various ovarian tumors was studied by the immunoperoxidase method using an antibody to human pancreatic amylase. Amylase was present in eight of 34 serous carcinomas and eight of 27 endometrioid carcinomas. However, only in one poorly differentiated serous carcinoma and two well-differentiated endometrioid carcinomas were a large number of amylase-reactive cells found. Five benign and three borderline serous tumors contained no amylase. Also, amylase was not detected in any of 34 mucinous tumors or five malignant clear cell tumors. The results obtained suggest that amylase will be a useful tumor marker, when present, for follow-up of endometrioid and serous carcinomas of the ovary.  相似文献   
995.
Six newborn infants with intrauterine supraventricular tachyarrhythmias (five cases of atrial flutter and one of supraventricular tachycardia) are described. Transplacental digitalisation was attempted in three cases. Supraventricular tachycardia associated with hydrops fetalis, detected in a fetus at a gestation of 31 weeks, was successfully converted to normal sinus rhythm eight days after the mother began treatment with digoxin. The serum concentration of digoxin in cord blood almost equalled the maternal concentration in three cases. In the remaining three cases treatment with digitalis was effective in converting tachyarrhythmias to sinus rhythm after delivery. With maintenance digoxin therapy, the prognosis of fetal tachyarrhythmias seems to be good, once conversion to sinus rhythm has been accomplished.  相似文献   
996.
997.
Histopathological characteristics of urinary bladder tumors induced in Syrian golden hamsters by 3,2'-dimethyl-4-aminobiphenyl (DMAB) were analyzed. DMAB was subcutaneously injected in corn oil at a concentration of 100 mg/kg once a week for 20 weeks and ethinyl estradiol (EE) was administered in the diet at a dose of 0.75 ppm throughout the experiment. A small group of animals was killed at week 20 and all survivors were killed at week 50. Urinary bladder carcinomas were induced in 14 of 18 hamsters (78%; 0.89/animal) in the DMAB+EE group and 11 of 17 (65%; 0.88/animal) in the DMAB alone group in males, and in 11 of 14 (79%; 0.79/animal) in the DMAB+EE group and 4 of 5 (80%; 0.80/animal) in the DMAB alone group in females examined between weeks 20 and 50. All were non-papillary invasive transitional cell carcinomas partly demonstrating glandular and/or squamous differentiation, and most carcinomas developed in the bladder neck. Degree of invasion was clearly correlated with degree of morphological atypism in the transitional cell carcinomas, hut not with squamous or glandular differentiation. No sex difference or modifying effect of EE on DMAB urinary bladder carcinogenesis was evident. No bladder carcinomas were observed in non-DMAB-treated animals.  相似文献   
998.
The levels of CA125, TPA, IAP, CEA, and ferritin in the serum were measured simultaneously in 68 healthy nonpregnant females and 133 patients with various gynecological diseases, and were subjected to statistical discriminant analysis for the diagnosis of ovarian cancer. The usefulness and the limits for diagnosis of various gynecological diseases were investigated for each tumor marker. Also, the diagnostic usefulness of the stepwise discriminant analysis employing the values of these five tumor markers in the serum in cases of ovarian cancer was compared with that of CA125 measurements alone. Because the frequency of cases with an elevated serum CA125 level increased more specifically in the ovarian cancer group than those of other tumor makers in the serum, this parameter was considered to be more useful for the diagnosis of ovarian cancer than the levels of the other tumor markers. The frequencies of cases with the elevated serum CA125 levels, however, also increased in the groups of patients with endometriosis and at an early stage of normal pregnancy more than in the group of healthy nonpregnant females. In the ovarian cancer patients, the discriminant analysis employing the values of CA125 and four other tumor markers in sera was more useful for early diagnosis, differential diagnosis, early detection of recurrences, and the determination of complete remission after therapy than the measurement of the serum CA125 level alone.  相似文献   
999.
We conducted a prospective, randomized, controlled trial comparing the efficacy of two doses of a reconstituted bovine surfactant (Surfactant TA) in premature infants requiring mechanical ventilation shortly after birth for respiratory distress syndrome. Forty-six infants weighing 1000–1499 g were randomized into two groups: a low-dose group (23 infants given a single dose of 60 mg surfactant lipid/kg) and a high-dose group (23 infants given a single dose of 120 mg/kg). The mean (SD) age at which surfactant was given was 5.5 (±1.2) h in the low-dose group and 6.0 (±1.5) h in the high dose group. Both treatments improved oxygenation (increased arterial-alvcolar PO2 ratio) with decreased mean airway pressure, the high-dose surfactant having a more beneficial effect in prolonging the response. Infants in the high-dose group had significantly less (P<0.05) incidence of both intraventricular haemorrhage and bronchopulmonary dysplasia. This prospective trial documents that a greater benefit can be obtained by increasing the dose of surfactant (120 mg/kg) beyond 60 mg/kg in the treatment of premature infants with severe respiratory distress syndrome (RDS).Abbreviations RDS respiratory distress syndrome - Surfactant TA Surfactant Tokyo-Akita - 5 kDa 5 kilodaltons - ELISA enzyme-linked immunosorbent assay - PDA patent ductus arteriosus - a/APO2 arterial-alveolar oxygen tension ratio - MAP mean airway pressure - 99mIc-DTPA 99m technetium diethylenetriamine pentacetate  相似文献   
1000.
After an inspection tour to farms and abattoirs in Australia and New Zealand, three Japanese persons simultaneously developed febrile illnesses in Japan. They generally had slight fever and general fatigue, followed by thrombocytopenia and hepatic dysfunction. However, no respiratory symptoms were observed. In one of the cases, severe thrombocytopenia (1.3 x 10(4)/microliter) and high fever up to 40 degrees C were observed. These clinical symptoms were compatible with Q fever. All of the cases showed four hold-elevations of IgM and IgG against Coxiella burnetii phase II between acute and convalescent sera by a serological test. C. burentii-DNA was also detected in the serum of one patient. Minocycline was highly effective in all cases. This report illustrates the typical clinical courses of acute Q fever.  相似文献   
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