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This study evaluated the role of magnetic resonance imaging (MRI) in the demonstration of the pelvic and perianal complications of Crohn's disease. Twenty five patients with active Crohn's disease were studied (12 male; mean age 41.1 years). MRI examinations were performed using a 1.5 Tesla system, within 14 days after clinical assessment. T1 and T2 weighted fast spin echo sequences in two or three orthogonal planes were performed, with fat suppression in some cases. The MRI results were correlated with surgical and clinical findings. In 16 patients, cutaneous, deep perineal or enterovesical fistulas or abscesses were diagnosed at MRI which showed close correlation with findings at examination under anaesthetic. In eight patients no fistulas or abscesses were seen at MRI nor was there any evidence of complications on clinical examination and flexible sigmoidoscopy. There was one false negative examination in a patient who had a colovesical fistula. In conclusion, MRI can accurately show the pelvic and perineal complications of Crohn's disease and may render examination under anaesthetic unnecessary.  相似文献   
584.
The need for endogenous FSH in the periovulatory events such as oocyte maturation, ovulation, luteinization, maintenance of luteal function and follicular maturation was examined in the cyclic hamster. A specific antiserum to ovine FSH, shown to be free of antibodies to LH and to cross-react with FSH of the hamster, was used to neutralize endogenous FHS at various times. Administration of this antiserum during pro-oestrus did not affect oocyte maturation and ovulation, as judged by the normality of the ova to undergo fertilization and normal implantation. It also had no effect on the process of luteinization or on the maintenance of luteal function as indicated by the normal levels of plasma and luteal progesterone during pro-oestrus and oestrus during the cycle and in pregnancy. All these processes were, however, disrupted by administration of an antiserum to ovine LH, thereby demonstrating their dependence on endogenous LH. Although FSH antiserum given at pro-oestrus did not prevent the imminent ovulation, it blocked the ovulation occurring at oestrus of the next cycle. This antiserum was effective in preventing the ensuing ovulation when given at any other time of the cycle until the morning of pro-oestrus. It is concluded that, in the hamster, high levels of FSH during pro-oestrus and oestrus are required for initiating maturation of a new set of follicles which are dependent on the trophic support of FSH throughout the cycle until the morning of pro-oestrus. Such follicles then appear to need only LH for subsequent ovulatory and associated processes.  相似文献   
585.
The Ocean State antitrust case illustrates the operation of the competitive marketplace in health insurance. Blue Cross, the dominant firm in Rhode Island, responded competitively to the entrance of a new competitor, Ocean State, in three ways: 1) a most-favored-nation clause, 2) creation of a PPO offering similar benefits as Ocean State, and 3) an adverse selection policy. These actions are assessed to be legitimate competitive responses and the decisions of the higher courts overturning the jury verdict against Blue Cross are supported.  相似文献   
586.
Crigler-Najjar syndrome type 1 (CN-1) is a recessively inherited, potentially lethal disorder characterized by severe unconjugated hyperbilirubinemia resulting from deficiency of the hepatic enzyme bilirubin-UDP-glucuronosyltransferase. In all CN-1 patients studied, structural mutations in one of the five exons of the gene (UGT1A1) encoding the uridinediphosphoglucuronate glucuronosyltransferase (UGT) isoform bilirubin-UGT1 were implicated in the absence or inactivation of the enzyme. We report two patients in whom CN-1 is caused, instead, by mutations in the noncoding intronic region of the UGT1A1 gene. One patient (A) was homozygous for a G-->C mutation at the splice-donor site in the intron, between exon 1 and exon 2. The other patient (B) was heterozygous for an A-->G shift at the splice-acceptor site in intron 3, and in the second allele a premature translation-termination codon in exon 1 was identified. Bilirubin-UGT1 mRNA is difficult to obtain, since it is expressed in the liver only. To determine the effects of these splice-junction mutations, we amplified genomic DNA of the relevant splice junctions. The amplicons were expressed in COS-7 cells, and the expressed mRNAs were analyzed. In both cases, splice-site mutations led to the use of cryptic splice sites, with consequent deletions in the processed mRNA. This is the first report of intronic mutations causing CN-1 and of the determination of the consequences of these mutations on mRNA structure, by ex vivo expression.  相似文献   
587.
This study is a continuation of the investgation of the influence of endogenous and exogenous interferon on influenza infection. Influenza B virus strains, both laboratory and fresh isolates, were found to be poor interferon inducers in contrast to influenza A virus strains. The study also showed that influenza B virus strains not only induced endogenous interferon poorly but were also resistant to exogenous interferon. This evidence points to marked differences of the investigated influenza B virus strains not only induced endogenous interferon poorly but were also resistant to exogenous interferon. This evidence points to marked differences of the investigated influenza B virus strains from influenza A virus strains which further indicates their peculiar nature.  相似文献   
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The GRAFTAC skin stapler with absorbable tacs has been used to attach split-skin grafts in 28 patients, under a variety of clinical situations, and the outcomes studied. This knowledge has been reviewed in the light of our existing experience with the more familiar metal staple. Details of the patients and their conditions are presented, with two illustrative case histories, including one where both Graftac and metal staples were used. The relative costs were analysed and an attempt made to compare the cost-effectiveness of tacs and staples. A rationale for use of the more expensive GRAFTAC stapler is presented.  相似文献   
590.
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