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Seid Hossein Mir-Madjlessi MD FACP Dr. Richard G. Farmer MD FACP Michael V. Sivak Jr MD FACP 《Digestive diseases and sciences》1987,32(2):145-154
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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Fan D Poste G Obrian C Seid C Ward N Earnest L Fidler I 《International journal of oncology》1992,1(7):735-742
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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Birth defect-related demise is mainly due to congenital heart defects. In the earlier stage of pregnancy, fetus problem can be identified by finding information about the fetus to avoid stillbirths. The gold standard used to monitor the health status of the fetus is by Cardiotachography(CTG), cannot be used for long durations and continuous monitoring. There is a need for continuous and long duration monitoring of fetal ECG signals to study the progressive health status of the fetus using portable devices. The non-invasive method of electrocardiogram recording is one of the best method used to diagnose fetal cardiac problem rather than the invasive methods.The monitoring of the fECG requires development of a miniaturized hardware and a efficient signal processing algorithms to extract the fECG embedded in the mother ECG. The paper discusses a prototype hardware developed to monitor and record the raw mother ECG signal containing the fECG and a signal processing algorithm to extract the fetal Electro Cardiogram signal. We have proposed two methods of signal processing, first is based on the Least Mean Square (LMS) Adaptive Noise Cancellation technique and the other method is based on the Wavelet Transformation technique. A prototype hardware was designed and developed to acquire the raw ECG signal containing the mother and fetal ECG and the signal processing techniques were used to eliminate the noises and extract the fetal ECG and the fetal Heart Rate Variability was studied. Both the methods were evaluated with the signal acquired from a fetal ECG simulator, from the Physionet database and that acquired from the subject. Both the methods are evaluated by finding heart rate and its variability, amplitude spectrum and mean value of extracted fetal ECG. Also the accuracy, sensitivity and positive predictive value are also determined for fetal QRS detection technique. In this paper adaptive filtering technique uses Sign-sign LMS algorithm and wavelet techniques with Daubechies wavelet, employed along with de noising techniques for the extraction of fetal Electrocardiogram.Both the methods are having good sensitivity and accuracy. In adaptive method the sensitivity is 96.83, accuracy 89.87, wavelet sensitivity is 95.97 and accuracy is 88.5. Additionally, time domain parameters from the plot of heart rate variability of mother and fetus are analyzed. 相似文献
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