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61.
Two autoimmune disease models were studied in rhesus monkeys: type II collagen-induced arthritis (CIA) and experimental allergic encephalomyelitis (EAE). Unrelated outbred animals were used in these studies. In both models disease resistant and susceptible individuals could be identified. Susceptibility correlated with in vitro cellular responsiveness to antigen in the CIA model. In both models resistant as well as susceptible individuals developed a humoral response to the inducing antigen. However, there is an indication that IgM antibodies play a crucial role in the induction of CIA. No clear association between major histocompatibility complex (MHC) type and disease incidence was found although a higher frequency of a certain DR type was observed in EAE susceptible monkeys. It is likely that both the antigen binding capacity of the MHC class II molecules and the T-cell repertoire play an important role in determining whether disease will develop or not.  相似文献   
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Herbal remedies generate more than 1.8 billion dollars in annual sales in the United States. Herbal products have been associated with a wide spectrum of hepatic toxicities. With the recent Women's Health Initiative Study demonstrating increased risk of breast cancer and cardiovascular events associated with hormone therapy, many women may resort to herbal remedies for persistent menopause symptoms. We report a case of autoimmune hepatitis likely triggered by the use of black cohosh (Actaea racemosa), an agent marketed to treat menopause symptoms. Given this case report, we recommend close monitoring of women using this herbal preparation.  相似文献   
64.
We report the development of a novel detection and typing methodology for human papillomaviruses (HPV) based on real-time PCR with the self-probing fluorescent primers known as Scorpions. This technique is quick, simple, specific, sensitive, and capable of estimating viral load per cell. We report the results of over 100 typing reactions performed on cell lines, biopsies, and cervical cytobrush samples which, when compared to the current reference HPV detection and typing technique, present a kappa value of 0.89. We further report preliminary data suggesting a relationship between viral load per cell and grade of cervical disease.  相似文献   
65.
Academic underachievement and the disruptive behavior disorders   总被引:3,自引:0,他引:3  
Academic underachievement (AU) was studied among 177 clinic-referred boys reliably diagnosed as having attention-deficit hyperactivity disorder (ADHD) or conduct disorder (CD). Unlike previous studies, the present study assessed AU using a formula that determined the discrepancy between a child's predicted level of achievement and actual level of achievement while controlling for regression and age effects. AU was associated with both ADHD and CD when the disorders were examined individually. However, when examined in multivariate logit model analyses, the apparent relation between CD and AU was found to be due to its comorbidity with ADHD. When boys with ADHD were divided into those with attention deficits only and those with co-occurring hyperactivity, findings did not support the hypothesis that the association with AU is stronger for attention deficits without co-occurring hyperactivity.  相似文献   
66.
Trichomonas vaginalis was grown in a modified Bushby's medium and putrescine, spermidine and spermine levels were determined in extracts from 24- and 48-h cultures and also in the culture media. All three polyamines were present in T. vaginalis extracts; the putrescine level and putrescine/spermidine ratio were much higher than those reported for other protozoa or for mammalian tissues. There were no significant differences between 24-h and 48-h amine levels per mg protein in these extracts, but amine levels per cell were higher at 24 than at 48 h. The spent culture media had a much higher putrescine content than corresponding uninoculated media and it was concluded that T. vaginalis secreted putrescine into the culture medium.  相似文献   
67.
Ten newly diagnosed patients with Wilms' tumor had blood and tumor samples taken for cytogenetic analysis. DNA was also extracted from these samples, along with blood obtained from both parents and an age- and sex-matched control. Molecular biological techniques were employed to study changes present in these samples with respect to chromosome 1. Two DNA probes, PIB 174 and PFBl, mapping to 1q12-qter and 1p12-pter, respectively, were examined for the presence of restriction fragment length polymorphisms (RFLPs) and to detect copy numbers of sequences homologous to the probes. These were normalized with respect to themselves and with regard to a control probe P30. No RFLPs were found with the restriction enzymes used. However, seven patients showed a marked alteration in hybridization signal in tumor and/or blood samples compared to control samples and the control probe. This was apparent using probe PFBl, but just failed to reach statistical significance using nonparametric testing. This would suggest that submicroscopic chromosome 1 changes are present more often in Wilms' tumor than previously recognized, and they may play a leading role in the genesis of this tumor.  相似文献   
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De novo UMP synthesis is a critical metabolic pathway for nucleic acid synthesis and for a variety of metabolic pathways. The pathway is a target for many widely used cancer chemotherapy agents, several of which are pyrimidine analogs. Humans and cattle have been described with mutations in UMP synthesis that lead to serious inborn errors of metabolism. Dihydroorotate dehydrogenase (EC 1.3.3.1) (DHODH) carries out the fourth committed step in the pathway and may also be important for mitochondrial electron transport and oxygen radical metabolism. We report here that the gene encoding this enzyme in humans is located in the chromosomal region 16q22. With the mapping of DHODH, the mapping of all the steps of UMP synthesis is complete. All three genes involved map to different human chromosomes. This information is important in consideration of regulation of UMP synthesis in mammals, including humans.  相似文献   
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