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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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Low-level laser therapy (LLLT) has been used to accelerate wound healing, yet questions remain concerning its therapeutic applications. This study aimed to compare the healing efficacy of helium-neon (He-Ne) red light (laser) and gallium aluminum arsenide (Ga-Al-As) infrared lasers at two different doses on hard palate wounds. In a randomized controlled study, 75 adult male mice were divided into five groups of 15 each, after undergoing identical surgical procedures; a control group, with no laser irradiation; HD1 and HD2 groups, treated with He-Ne laser (wavelengths 632.8 nm, power 5 mW, and spot size 0.02 cm2) at doses of 4 J/cm2 and 7.5 J/cm2 respectively; and GD1 and GD2 groups, treated with Ga-Al-As laser (wavelengths 830 nm, peak power 25 mW, and spot size 0.10 cm2) at the doses of 4 J/cm2 and 7.5 J/cm2, respectively. Five animals from each group were killed on the third, seventh, and 14 days after surgery, and biopsies were made for histological analysis. On the 3rd and 7th day after the surgery, the number of polymorphonuclear cells (PMN) in HD1, HD2, GD1, and GD2 groups was significantly lower than that of the control group. On the 7th and 14th day, the fibroblasts and new blood vessels counts and collagen density fibers in HD1, HD2, GD1, and GD2 groups were also significantly higher than that of the control groups, and the fibroblast counts and collagen density fibers in HD1 and HD2 groups were higher than that of the GD1 and GD2 groups. LLLT with He-Ne laser compared to Ga-Al-As laser has a positive healing effect on hard palate gingival wounds in mice regardless of the radiation dose.  相似文献   
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Background

Several studies have demonstrated skills transfer after virtual reality (VR) simulation training in laparoscopic surgery. However, the impact of VR simulation training on transfer of skills related to laparoscopic colectomy remains not investigated. The present study aimed at determining the impact of VR simulation warm-up on performance during laparoscopic colectomy in the porcine model.

Methods

Fourteen residents naive to laparoscopic colectomy as surgeons were randomly assigned in block to two groups. Seven trainees completed a 2-h VR simulator training in the laparoscopic sigmoid colectomy module (study group). The remaining seven surgeons (control group) underwent no intervention. On the same day, all participants performed a sigmoid colectomy with anastomosis on a pig. All operations were video recorded. Two board-certified expert colorectal surgeons independently assessed performance during the colectomy on the swine. Examiners were blinded to group assignment. The two examiners used a previously validated clinical instrument specific to laparoscopic colectomy. The primary outcome was the generic and specific skills score values.

Results

Surgeons undergoing short-duration training on the VR simulator performed significantly better during laparoscopic colectomy on the pig regarding general and specific technical skills evaluation. The average score of generic skills was 17.2 (16.5–18) for the control group and 20.1 (16.5–22) for the study group (p = 0.002). The specific skills average score for the control group was 20.2 (19–21.5) and 24.2 (21–27.5) for the study group (p = 0.001). There was acceptable concordance (Kendall’s W) regarding the video assessment of generic (W = 0.78) and specific skills (W = 0.84) between the two examiners.

Conclusions

A single short-duration VR simulator practice positively impacted surgeons’ generic and specific skills performance required to accomplish laparoscopic colectomy in the swine model.  相似文献   
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