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41.
An in vitro chemosensitivity test using collagen gel matrix assay with quantitative evaluation of cell viability using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide was applied to 40 human genitourinary tumor specimens. Chemosensitivity was determined in 34 (85%) of the 40 specimens. The anticancer drugs tested against 14 renal cell carcinomas showed lower activities than against 15 transitional cell carcinomas with different sensitivity patterns among the individual specimens demonstrated. Our assay system could be successfully applied to human genitourinary tumors and can be used as a practical and highly reproducible chemosensitivity test in vitro.  相似文献   
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Vaccination with idiotypic protein protects against B-cell lymphoma, mainly through anti-idiotypic antibody. For use in patients, DNA vaccines containing single-chain Fv derived from tumor provide a convenient alternative vaccine delivery system. However, single-chain Fv sequence alone induces low anti-idiotypic response and poor protection against lymphoma. Fusion of the gene encoding fragment C of tetanus toxin to single-chain Fv substantially promotes the anti-idiotypic response and induces strong protection against B-cell lymphoma. The same fusion design also induces protective immunity against a surface Ig-negative myeloma. These findings indicate that fusion to a pathogen sequence allows a tumor antigen to engage diverse immune mechanisms that suppress growth. This fusion design has the added advantage of overcoming potential tolerance to tumor that may exist in patients.  相似文献   
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An 82 year old man developed antibodies against coagulation factor VIII:C without any apparent cause. Bleeding from the soft tissue cavity could not be controlled by factor VIII:C concentrates, immunosuppression with steroids and intravenous immunoglobulin therapy in the standard dosages. However, a single injection of Epsilon Aminocaproic Acid (EACA) instilled into the cavity under aseptic precautions achieved lasting hemostasis with resultant wound healing.  相似文献   
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The purpose of this study was to see whether and how the number of suicide attempters with alcohol problems and their drinking habits differ between the Nordic areas under study. Problem-drinkers were defined as persons who themselves felt that they had an alcohol problem. The analyses were based on data collected at five Nordic research centers participating in the WHO/Euro Multicentre Study on Parasuicide, namely: Helsinki (Finland); Ume? and Stockholm (Sweden); S?r-Tr?ndelag (Norway); and Odense (Denmark). The results showed that the frequency of problem-drinking among suicide attempters differed markedly between the areas under study; the Finnish male and the Danish female suicide attempters included the highest proportions of self-identified problem-drinkers. The pattern of drinking among the suicide attempters also differed between the areas. The analyses indicate that the point when alcohol becomes a problem to somebody, especially to a degree that it increases the risk of suicidal behavior, not only depends on how much and how often the person drinks alcohol; the prevailing drinking pattern, the attitudes towards drinking alcohol, and the level of social control are also important factors to take into consideration when relations between alcohol and suicidal behavior are under study.  相似文献   
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An iron-repressible 44-kDa outer membrane protein plays a crucial role in the acquisition of heme by the anaerobic bacterium Bacteroides fragilis. The DNA sequence of the gene encoding the 44-kDa protein (hupA) was determined. The hupA gene encodes a protein of 431 amino acid residues with a calculated molecular mass of 48,189 Da. The hupA gene is preceded by an open reading frame of 480 bp that probably encodes a protein with a calculated molecular mass of 18,073 Da. hupA and this open reading frame are likely organized in an operon, and a sequence homologous to the Escherichia coli consensus Fur box was present in the putative promoter region of the operon. Heme-binding studies showed that HupA binds heme. Analysis of the deduced amino acid sequence revealed signature heme-binding consensus motifs, characteristic of heme lyases. Subcellular localization studies in E. coli revealed that HupA was mainly found in the cytoplasmic membrane but not in the outer membrane of E. coli. This suggested that B. fragilis uses another strategy for the translocation of this outer membrane protein across its cell envelope than E. coli does. HupA did not have significant homology with other putative bacterial heme receptors.  相似文献   
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We report the cloning and expression of the fifth member of the mammalian UDP-GalNAc:polypeptide N-acetylgalactosaminyltransferase (ppGaNTase) family. Degenerate polymerase chain reaction amplification and hybridization screening of a rat sublingual gland (RSLG) cDNA library were used to identify a novel isoform termed ppGaNTase-T5. Conceptual translation of the cDNA reveals a uniquely long stem region not observed for other members of this enzyme family. Recombinant proteins expressed transiently in COS7 cells displayed transferase activity in vitro. Relative activity and substrate preferences of ppGaNTase-T5 were compared with previously identified isoforms (ppGaNTase-T1, -T3, and -T4); ppGaNTase-T5 and -T4 glycosylated a restricted subset of peptides whereas ppGaNTase-T1 and -T3 glycosylated a broader range of substrates. Northern blot analysis revealed that ppGaNTase-T5 is expressed in a highly tissue-specific manner; abundant expression was seen in the RSLG, with lesser amounts of message in the stomach, small intestine, and colon. Therefore, the pattern of expression of ppGaNTase-T5 is the most restricted of all isoforms examined thus far. The identification of this novel isoform underscores the diversity and complexity of the family of genes controlling O-linked glycosylation.  相似文献   
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The relationship between the prognosis and age of patients with gastric cancer is controversial. To evaluate whether there is a biological characteristic specific to the age of patients, we examined the clinical characteristics of patients with gastric cancer with special reference to their age. Based on a prospective database, a retrospective study of 419 patients who underwent radical gastrectomy for cure in the past 6 years was conducted. Clinical characteristics including gender, gross appearance of the tumour (Borrmann's classification, tumour location), histopathology (depth of tumour invasion, lymph node status, Lauren's classification and degree of tumour cell differentiation) and TNM tumour stage were analysed in six different age groups (< 39, 40-49, 50-59, 60-69, 70-79, > 80 years). The mean age of the 419 patients was 64.6 years (range from 26-91) and the peak age incidence of gastric cancer (46.3%) was in the 60-69 year old age group. The male: female ratio was 4.6:1 on the whole and male gender predominated at ages > 60. The proportion of diffuse type tumours (68.4%) by Lauren's criteria in the young age group (< 39 yrs) decreased with age (25% in the > 80 years group; P < 0.001). Similarly, the proportion of poorly-differentiated tumours (89.5%) in the young age group (< 39 yrs) decreased with advancing age (P < 0.001). These findings suggest that both diffuse type and poorly-differentiated tumours predominate in younger patients and, without considering the factor of delay in diagnosis, may explain the poorer prognosis demonstrated in younger patients.  相似文献   
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