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1.
Study Objective . To characterize cytochrome P450 (CYP) 3A4 activity in premenopausal and postmenopausal women by evaluating the urinary 6-β-hydroxycortisokcortisol ratio. Design . Prospective study. Subjects . Thirteen premenopausal and 13 postmenopausal women who were healthy and not receiving drugs known to affect CYP3A4 activity. Interventions . Beginning on day 2 of menses, premenopausal women collected first morning urine samples every other day for a complete menstrual cycle. Postmenopausal women collected first morning urine every other day for 28 days. Measurements and Main Results . Mean weekly 6-β-hydroxycortisol:cortisol ratios did not differ during the phase (week) of the menstrual cycle. Daily ratios did not differ in postmenopausal women. No difference between premenopausal and postmenopausal women was found on comparing overall median ratios. Conclusion . Cytochrome P450 3A4 activity as measured by 6-β-hydroxy cortisol:cortisol ratio did not differ by week of menstrual cycle, suggesting no menstrual cycle-related changes. Menopause does not appear to be associated with differences in CYP3A4 activity, compared with premenopause.  相似文献   
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BACKGROUND: Gastric cancer (GC) is the leading cause of cancer deaths in China. Our study prospectively evaluated the impact of repeated endoscopic screens on GC mortality in a high-risk population in China. METHODS: Between 1989 and 1999, a population-based gastroscopic screening was conducted in 4,394 residents of Linqu County, China, a region with the highest rates of GC worldwide. Residents ages 35 to 64 years received initial gastroscopies with biopsies in 1989. Repeated endoscopies were performed in 1994 and 1999. Cancer occurrences and deaths were actively monitored throughout the entire period until July 2000. Mortality from GC was compared with expected values based on mortality rates obtained for Linqu in the 1990-1992 Chinese Cancer Mortality Survey. RESULTS: Between March 1989 and July 2000, 39,303 person-years were accumulated; 85 new GCs occurred, 29 (34.5%) were in early stage. Fifty-eight cases (68%) were identified at one of the screens. The number of observed deaths from GC (37) was close to the expected (36.8). The standardized mortality ratio was 1.01 (95% CI 0.72-1.37) for the entire cohort, 1.13 (95% CI 0.77-1.57) for males, and 0.65 (95% CI 0.26-1.32) for females. CONCLUSIONS: Despite high population coverage with repeated screens, no reduction in GC mortality was observed in this high-risk population in China.  相似文献   
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INTELLECTUAL FUNCTIONS OF PATIENTS WITH CHILDHOOD-ONSET EPILEPSY   总被引:21,自引:2,他引:19  
The intellectual functions of 64 epileptic patients who had had an initial evaluation between five and 16 years of age, including the WISC, were re-evaluated after a period of at least five years. In general the seizure states had improved, and 50 per cent were in remission for between two and eight years. All but four were still taking at least one anticonvulsant drug. WISC IQ estimates showed a slight decrease. Verbal and performance areas could be differentially affected, and a gain in one could be offset by a loss in the other, so the Full-scale IQ might not be a reliable measure of day-to-day performance. Those whose seizures remained uncontrolled had a statistically significant decrease in performance IQ, whereas in general it was stable or increased for patients in remission. There was evidence that decreased IQ indicated slower mental growth rather than loss of previously acquired function. Phenobarbital but not phenytoin levels were inversely correlated with IQ, suggesting that the upper limit of the 'therapeutic range' of phenobarbital may already be toxic with regard to learning abilities. To optimize an epileptic child's functioning in school and to prevent long-term intellectual problems, it is advisable that IQ testing should be part of the routine initial evaluation, and that drug levels should be checked at regular intervals.  相似文献   
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BACKGROUND: Normal endothelial function depends on nitric oxide (NO) release by endothelial cells. Asymmetric dimethylarginine (ADMA), by competing with L-arginine, inhibits NO production and may lead to endothelial dysfunction and atherosclerotic development. Our aim was to ascertain the association between ADMA and coronary artery calcification (CAC), a marker of atherosclerotic coronary disease burden. DESIGN: A nested case-control study within the Coronary Artery Risk Development in Young Adults (CARDIA) cohort, an observational study among young adults residing in four US cities. METHODS: Participants were 263 white and black male and female cases with the presence of CAC and 263 sex and race-matched controls without evidence of CAC by computed tomography, 33-47 years old in 2000-2001. RESULTS: The median level (range) of ADMA was significantly higher in cases (0.55; 0.20-2.22 micromol/l) than in controls (0.53; 0.32-1.30 micromol/l; P=0.03). In conditional logistic regression adjusting for age, field center, educational attainment, smoking status, alcohol consumption, body mass index, waist circumference, hypertension, diabetes, low-density lipoprotein and high-density lipoprotein-cholesterol, triglycerides, renal function and C-reactive protein, the highest tertile of ADMA, compared with the lowest tertile, was associated with 1.80 (95% confidence interval 1.03-3.15) increased odds of the presence of any CAC. By linear regression, a significant independent relationship was also found between ADMA and the degree of CAC. CONCLUSION: These results support a role for ADMA as a biochemical marker of CAC.  相似文献   
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Introduction As many as one quarter of all cancer survivors report traumatic stress symptoms from cancer-related experiences. While the majority of these patients do not meet the criteria for posttraumatic stress disorder (PTSD), there is growing evidence that subsyndromal symptoms can significantly contribute to functional impairment and negative health outcomes. Treatment options for the hallmark symptoms of traumatic stress—unpleasant, intrusive thoughts and avoidant behaviors—have not been well investigated for the cancer survivorship population. Materials and methods Seven female cancer survivors with traumatic stress symptoms from cancer-related experiences and no other major psychopathology, were enrolled to receive three sessions of Neuro-Emotional Technique (NET), a brief, targeted treatment that combines traditional desensitization principles with complementary modalities. Results Psychological outcome measures (Impact of Event Scale (IES) and Subjective Units of Distress (SUD) and physiological measures (Heart Rate (HR) and Skin Conductance Level (SCL) demonstrated the following changes: 71% on IES, 88% SUD, 74% on HR, and 65% on SCL following the intervention. Statistically significant changes were observed for all four parameters, and effect size g for proportion improved were 0.50 each for IES, SUD, and HR, and 0.20 for SCL. Conclusions These cases suggest feasibility of the NET intervention for cancer-related traumatic stress and the potential for change in symptoms and physiological reactivity. Further investigation is needed to determine the specific and long-term effects of such an approach. Implications for cancer survivors Traumatic stress from cancer-related experiences might represent a constellation of symptoms that are amenable to brief, targeted interventions. This study was supported by the O.N.E. Research Foundation  相似文献   
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A sample enriched for familial combined hyperlipidemia (FCHL) was examined for evidence of an association between genotype at an apolipoprotein B (apoB) elevating locus defined by complex segregation analysis and FCHL. Complex segregation analysis detected a locus with a large effect on plasma apoB levels and was used to compute the most probable genotype of family members. None of the 35 normolipidemic adults carried a copy of the allele associated with elevated apoB levels, yet 58% of the 109 adults with FCHL carried 1 (29%) or 2 (28%) copies. Two of 28 (7%) normal children had 1 copy of this allele and none had 2 copies, while 88 of 182 (48%) children with FCHL had 1 (26%) or 2 (22%) copies. Further, 4l of 48 (85%) individuals classified as having hyperapobetalipoproteinemia did not carry a copy of this “elevated apoB” allele. Therefore, the presence of the allele associated with elevation of apoB level is highly predictive of FCHL and this association cannot be explained solely by the presence of elevated apoB levels in FCHL, suggesting that the locus controlling apoB levels may play an etiologic role in FCHL. © 1993 Wiley-Liss, Inc.  相似文献   
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Sharon Gohari  BS    Charles Gambla  MD    Mary Healey  RN    Gail Spaulding  RN    Kenneth B. Gordon  MD    James Swan  MD    Brian Cook  MD    Dennis P. West  PhD    Jean-Christophe Lapiere  MD 《Dermatologic surgery》2002,28(12):1107-1114
BACKGROUND: Human Skin Substitute (Apligraf, Organogenesis, Inc., Canton, MA) is a bi-layered tissue-engineered living biological dressing developed from neonatal foreskin. It consists of a bovine collagen matrix containing human fibroblasts with an overlying sheet of stratified human epithelium containing living human keratinocytes. Human Skin Substitute (HSS) appears to be immunologically inert, and has shown usefulness in the treatment of chronic and acute wounds. OBJECTIVE: Primary objectives were to evaluate the safety and efficacy of HSS in the treatment of full-thickness wounds in a prospective case series. Secondary objectives were to determine the rate of complete wound reepithelialization, incidence of complete wound healing, pain at wound site, overall cosmetic outcome, and patient satisfaction. METHODS: Fourteen patients were enrolled in the study, of which 12 were evaluable. HSS was applied in a blinded fashion to 6 of the patients immediately following Mohs or excisional surgery for skin cancer. The remaining 6 patients were allowed to heal by secondary intention. Both groups were evaluated at weekly appointments until complete reepithelialization occurred. During each evaluation, wound quality was assessed through the Vancouver Burn Scar Assessment Scale by the investigator and an independent blinded dermatologist. The investigator, blinded observer, and patient further evaluated the cosmetic outcome of the wound through the use of a Visual Analog Scale over a 6-month period. RESULTS: HSS patients and secondary intention patients were equivalent in comorbid factors such as pain, erythema, edema, exudate, infection, or hematoma between the groups. The incidence of complete wound healing at 6 months was 100% for both groups. Both groups also appeared to heal at similar rates, as defined by the complete reepithelialization of the wound. HSS patients ultimately resulted in more pliable and less vascular wounds as defined by the Vancouver Burn Scar Assessment Scale. Patient satisfaction with cosmetic outcome in both groups was positive at 6 months. CONCLUSIONS: HSS appears to be a safe, well-tolerated biological dressing with equivalent comorbid factors to secondary intention healing. HSS, however, seems to produce a more pliable and less vascular scar than those developed through healing by secondary intention. HSS also appears to produce more satisfactory cosmetic results when compared to secondary intention healing.  相似文献   
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