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1.
A human tumor xenograft (L56Br-X1) was established from a breast cancer axillary lymph node metastasis of a 53-year-old woman with a BRCA1 germ-line nonsense mutation (1806C>T; Q563X), and a cell line (L56Br-C1) was subsequently derived from the xenograft. The xenograft carries only the mutant BRCA1 allele and expresses mutant BRCA1 mRNA but no BRCA1 protein as determined by immunoprecipitation or Western blotting. The primary tumor, lymph node metastasis, and xenograft were hypodiploid by DNA flow cytometry, whereas the cell line displayed an aneuploidy apparently developed via polyploidization. Cytogenetic analysis, spectral karyotyping, and comparative genomic hybridization of the cell line revealed a highly complex karyotype with numerous unbalanced translocations. The xenograft and cell line had retained a somatic TP53 missense mutation (S215I) originating from the primary tumors, as well as a lack of immunohistochemically detectable expression of steroid hormone receptors, epidermal growth factor receptor, human epidermal growth factor receptor 2 (HER-2), and keratin 8. Global gene expression analysis by cDNA microarrays supported a correlation between the expression profiles of the primary tumor, lymph node metastasis, xenograft, and cell line. We conclude that L56Br-X1 and L56Br-C1 are useful model systems for studies of the pathogenesis and new therapeutic modalities of BRCA1-induced human breast cancer.  相似文献   
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In vivo studies of intestinal carnitine absorption in rats   总被引:2,自引:0,他引:2  
We have studied small intestinal absorption of carnitine in vivo using a combination of segmental perfusion techniques and bolus intraluminal injection. We found evidence of a partially saturable absorption process (with Km values of 1035 and 1267 microM for jejunum and ileum calculated for the saturable component) that appeared to be separate from the imino acid transport system. Absorption was characterized by slow mucosal uptake, prolonged mucosal retention, and a very slow mucosal exit process with blood levels of [3H] carnitine still rising 8 h after intraluminal administration. We have also demonstrated the presence of carnitine acetyltransferase in intestinal mucosa and have shown that the intestine forms significant amounts of acetylcarnitine from exogenous carnitine.  相似文献   
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AIM: To study if and how physicians use the irritable bowel syndrome (IBS) diagnostic criteria and to assess treatment strategies in IBS patients. METHODS: A questionnaire was sent to 191 physicians regarding IBS criteria, diagnostic methods and treatment. Furthermore, 94 patients who were diagnosed with IBS underwent telephone interview. RESULTS: A total of 80/191 (41.9%) physicians responded to the survey. Overall, 13 patients were diag-nosed monthly with IBS by specialists in gastroenterology (SGs) and 2.5 patients by general practitioners (GPs). All the SGs knew of the criteria to diagnose IBS, as did 46/70 (65.7%) GPs. Seventy-nine percent used the patient’s history, 38% used a physical examination, and 38% exclusion of other diseases to diagnose IBS. Only 18/80 (22.5%) physicians used specific IBS criteria. Of the patients interviewed, 59/94 (62.8%) knew they had experienced IBS. Two out of five patients knew IBS and had seen a physician because of IBS symptoms. Half of those received a diagnosis of IBS. A total of 13% were satisfied with treatment. IBS affected daily activities in 43% of cases. CONCLUSION: Half of the patients with IBS who consulted a physician received a diagnosis. Awareness and knowledge of diagnostic criteria for IBS differ between SGs and GPs.  相似文献   
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Context

Our aim was to present a summary of the Second International Consultation on Bladder Cancer recommendations on the diagnosis and treatment options for non–muscle-invasive urothelial cancer of the bladder (NMIBC) using an evidence-based approach.

Objective

To critically review the recent data on the management of NMIBC to arrive at a general consensus.

Evidence acquisition

A detailed Medline analysis was performed for original articles addressing the treatment of NMIBC with regard to diagnosis, surgery, intravesical chemotherapy, and follow-up. Proceedings from the last 5 yr of major conferences were also searched.

Evidence synthesis

The major findings are presented in an evidence-based fashion. We analyzed large retrospective and prospective studies.

Conclusions

Urothelial cancer of the bladder staged Ta, T1, and carcinoma in situ (CIS), also indicated as NMIBC, poses greatly varying but uniformly demanding challenges to urologic care. On the one hand, the high recurrence rate and low progression rate with Ta low-grade demand risk-adapted treatment and surveillance to provide thorough care while minimizing treatment-related burden. On the other hand, the propensity of Ta high-grade, T1, and CIS to progress demands intense care and timely consideration of radical cystectomy.  相似文献   
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BACKGROUND: Selective inhibitors of cyclooxygenase (COX)-2 may provoke less gastric damage and platelet inhibition than conventional non-steroidal anti-inflammatory drugs. AIMS: We compared the biochemical and gastrointestinal effects of nimesulide, a potent and selective COX-2 inhibitor, with naproxen which exhibits no selectivity. SUBJECTS: Thirty six healthy volunteers were randomised to nimesulide 100 mg or naproxen 500 mg twice daily for two weeks in a double blind, crossover study with a washout between treatments. METHODS: Gastrointestinal side effects were assessed by endoscopy, and by estimation of small intestinal absorption-permeability and inflammation. Comparisons were made between variables at the end of each treatment phase. RESULTS: Nimesulide caused significantly less gastric injury using the modified Lanza score (p<0.001) as well as reduced duodenum injury (p=0.039). Nimesulide had lower visual analogue scores (VAS) for haemorrhage and erosive lesions in the stomach (p<0.001) and for mucosal injection in the duodenum (p=0.039). Naproxen increased excretion of calprotectin, a marker of intestinal inflammation (5.5 (1.2) to 12.1 (2.1) mg/l) while nimesulide had no effect (treatment difference p=0.03). Naproxen abolished platelet aggregation to arachidonic acid and suppressed serum thromboxane B(2) (TXB(2)) by 98%, indices of COX-1 activity. In contrast, nimesulide had no significant effect on platelet aggregation, although it reduced serum TXB(2) by 29%. Production of prostaglandin E(2) and prostacyclin by gastric biopsies, also COX-1 dependent, was inhibited by naproxen, but not by nimesulide. COX-2 activity, determined as endotoxin induced prostaglandin E(2) formation in plasma, was markedly suppressed by both treatments. INTERPRETATION: Nimesulide has preferential selectivity for COX-2 over COX-1 in vivo at full therapeutic doses and induces less gastrointestinal damage than that seen with naproxen in the short term.  相似文献   
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Metabolic side-effects of atypical antipsychotics have led to concern about their relative safety compared with low doses of conventional neuroleptics. Akathisia is an often misdiagnosed side-effect, which leads to non-compliance and sometimes even exacerbation of psychosis or suicidal behaviour. In fact, little is known about the differences between antipsychotic drugs in clinical practice, since only as few as 20% of patients may be eligible for studies comparing antipsychotic medications with each other. The aim of this study was to find out if the use of conventional antipsychotics is associated with an increased risk of akathisia (compared with atypical antipsychotics) even when low doses of conventional antipsychotics are used. The Barnes Akathisia Rating Scale was used to evaluate akathisia in 100 outpatients on antipsychotic medication. Conventional antipsychotics were associated with an increased risk of akathisia compared with atypical antipsychotics, although the chlorpromazine equivalent doses of conventional antipsychotics were lower than those of the atypicals. An additional akathisia-provoking effect of SSRIs could not be ruled out. The results suggest favouring atypical antipsychotic medication in patients who may easily develop akathisia.  相似文献   
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