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Six cases of bile duct carcinoma were encountered among 1207 patients with ulcerative colitis, a prevalence rate of 0.5%. The relative risk of bile duct carcinoma in patients with ulcerative colitis was 31.3. Colitis was extensive in all six patients with a mean duration of 23.2 years before the diagnosis of carcinoma. The mean age at the diagnosis of carcinoma was 38.5 years. Three patients had undergone colectomy 5–16 years earlier, and in four patients pericholangitis and sclerosing cholangitis preexisted. The tumors, histologically adenocarcinomas, were located in the common bile duct in five patients and in the hepatic duct in one. The mean survival was 11.8 months (one patients is still alive with recurrent carcinoma). Pericholangitis and sclerosing cholangitis is a frequent preexisting lesion in patients with bile duct carcinoma complicating ulcerative colitis and may be considered a premalignant lesion in these patients. Both sclerosing cholangitis and bile duct carcinoma are rare in Crohn's disease.  相似文献   
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A variety of resistance phenotypes to cytotoxic agents in bacteria, protozoa parasites and mammalian cells are mediated by evolutionarily conserved proteins of the mdr family. The finding that chloroquine resistance in the malarial parasite, Plasmodium falciparum, that is mediated by an mdr-1 gene product can be circumvented by tricyclic antidepressant drugs has stimulated the present study to assess whether this class of agents might also modulate the multidrug resistance (MDR) phenotype(s) in mammalian tumor cells. The possible chemosensitizing effects of nine antidepressant drugs have been tested against the UV-2237M murine fibrosarcoma line and its MDR variant. At nontoxic concentrations all nine antidepressants markedly enhanced the cytotoxicity of ADR against the parental cells but were much less effective against the MDR cells. The most active antidepressant, trazodone, also enhanced the cytotoxicities of vinblastine and vincristine, but not those of actinomycin D, mitomycin C, or 5-fluorouracil. The parental cells treated with trazodone exhibited an increased accumulation of intracellular ADR, but lacked detectable alterations in the expression and drug-binding activity of plasma membrane P-glycoprotein, and trazodone did not affect the activities of isolated protein kinase C and calmodulin. These data suggest that the antidepressant drug trazodone may be useful in the reversal of the intrinsic drug resistance of tumor cells that express low levels of P-glycoprotein.  相似文献   
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BACKGROUND: The application of health-related quality of life (HRQOL) as a pediatric population health measure may facilitate risk assessment and resource allocation, the tracking of community health, the identification of health disparities, and the determination of health outcomes from interventions and policy decisions. OBJECTIVE: To determine the feasibility, reliability, and validity of the 23-item PedsQL 4.0 (Pediatric Quality of Life Inventory) Generic Core Scales as a measure of pediatric population health for children and adolescents. DESIGN: Mail survey in February and March 2001 to 20 031 families with children ages 2-16 years throughout the State of California encompassing all new enrollees in the State's Children's Health Insurance Program (SCHIP) for those months and targeted language groups. METHODS: The PedsQL 4.0 Generic Core Scales (Physical, Emotional, Social, School Functioning) were completed by 10 241 families through a statewide mail survey to evaluate the HRQOL of new enrollees in SCHIP. RESULTS: The PedsQL 4.0 evidenced minimal missing responses, achieved excellent reliability for the Total Scale Score (alpha =.89 child;.92 parent report), and distinguished between healthy children and children with chronic health conditions. The PedsQL 4.0 was also related to indicators of health care access, days missed from school, days sick in bed or too ill to play, and days needing care. CONCLUSION: The results demonstrate the feasibility, reliability, and validity of the PedsQL 4.0 as a pediatric population health outcome. Measuring pediatric HRQOL may be a way to evaluate the health outcomes of SCHIP.  相似文献   
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OBJECTIVE: To describe the development and validation of the Barriers to Care Questionnaire (BCQ). METHODS: The 39-item BCQ was developed through review of the literature, focus groups, and cognitive interviews of Spanish- and English-speaking parents of children with chronic health conditions. Barriers to care are conceptualized as a multidimensional construct consisting of pragmatics, health knowledge and beliefs, expectations about care, skills, and marginalization. The BCQ was field tested in 3 samples of children with special health care needs (CSHCN). RESULTS: Response rate for the field test was 77.2%. There were minimal missing data (0.08%), no floor effects, and minimal ceiling effects (3.8%, total scale). Internal consistency reliability (alpha) for the BCQ total scale was.95 and subscale alpha ranged from.75 to.91. The BCQ total scale and subscales correlated in the expected direction with validated measures of primary care characteristics and health-related quality of life. BCQ scores were higher (fewer barriers) for children with a primary care physician and for those who reported no problems getting care or foregone care. CONCLUSION: The BCQ is a feasible, reliable, and valid instrument for measuring barriers to care for CSHCN. Its use may inform efforts to support consumer choice, enhance provider accountability, and spur quality improvement.  相似文献   
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Ulcerative colitis is a chronic recurrent disease with incomplete treatment options. The current article evaluated the effect of sodium valproate on acetic acid-induced ulcerative colitis in rats. Rats were randomly distributed into six groups including Sham group, colitis control group, sodium valproate treatment groups (50, 100 and 300 mg/kg, i.p.) and dexamethasone-treatment group. Dexamethasone was used as a reference drug. Colitis was induced by intracolonic instillation of 2 mL of 3% acetic acid solution. The efficacy of sodium valproate was evaluated by macroscopical and histopathological scoring systems, hematocrit measurement as well as biochemical analysis including myeloperoxidase (MPO) and pro-inflammatory cytokines assessment. Sodium valproate, particularly with doses of 100 and 300 mg/kg significantly improved weight loss, and macroscopic damage, reduced ulcer area, colon weight, microscopic colitis index and elevated hematocrit level. Biochemical experiments showed elevated levels of colonic MPO activity, interleukin 1β (IL-1β), interleukin 6 (IL-6) and tumor necrosis factor-α (TNF-α) in colitis control group. Treatment with sodium valproate at the doses of 100 and 300 mg/Kg) decreased the MPO activity and colonic concentrations of IL-1β, IL-6 and TNF-α. The results provide evidence that sodium valproate has a protective effect in acetic acid-induced ulcerative colitis which might be due to its anti-inflammatory activities, and it may be useful in patients with ulcerative colitis.  相似文献   
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Current paper reviews the pharmacological activities, therapeutic indications and phytochemicals of M. longifolia. This herb has been consumed traditionally for the treatment of various diseases, including gastrointestinal disorders, respiratory disorders, infectious diseases, inflammatory diseases, as well as menstrual disorders. In the modern era, various pharmacological activities have been confirmed for M. longifolia, such as anti-parasitic, antimicrobial, anti-insect, antimutagenic, antinociceptive, anti-inflammatory, antioxidant, keratoprotective, hepatoprotective, anti-diarrhea, and spasmolytic effects. The plant showed therapeutic benefits in irritable bowel syndrome, amenorrhea and oligomenorrhea, and oxidative stress-associated diseases as well. A vast variety of natural components such as flavonoids, phenolic acids, cinnamates, ceramides, sesquiterpenes, terpenes, and terpenoids have been suggested to be responsible for the pharmacological action of M. longifolia. These natural products can be considered as novel medicinal sources for developing new drugs. Further investigations to explore therapeutic efficacy, tolerability, and pharmaceutical properties of M. longifolia phytochemical agents are recommended.  相似文献   
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