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71.
5-Flourouracil(5-FU) is one of well known anti-cancer drugs, but its toxicity in normal lymphocytes remains a major problem in chemotherapy. The eastern traditional drug, Bupleuri radix(BR), has been used for the treatment of liver diseases and contains series of triterpene saponins.  相似文献   
72.
OBJECTIVES. To test for socioeconomic differences in some biological and behavioral risk factors for obesity in a representative and contemporary sample of adolescents. METHODS: Cohort study of 2 016 randomly selected 12- and 15-year-olds representative of Northern Ireland, studied in 2000. We tested for differences in obesity risk factors based on a priori hypotheses between adolescents from affluent (n=487) versus deprived (n=237) families. Potential risk factors were dietary energy and macronutrient intake, habitual physical activity, TV viewing and computer use, and physical fitness. RESULTS: Adolescents of higher socioeconomic status reported significantly lower habitual energy intake (210 kJ/kg/d SD 80 vs. 229 kJ/kg/d SD 91, p < 0.01); significantly higher levels of habitual physical activity (physical activity score 25.9 SD 16.6 vs. 20.9 SD 16.4, p < 0.001), and had significantly higher cardiorespiratory fitness (estimated VO2 max 46.2 ml/kg/min SD 8.4 vs. 43.4 ml/kg/min SD 8.3, p < 0.001). Prevalence of overweight and obesity (BMI >85th percentile) in the cohort was 29.1% and was slightly but not significantly higher in the low (33.8%) versus the high (28.5%) socioeconomic groups. CONCLUSIONS: Differences in some of the biological and behavioral risk factors for obesity exist between adolescents of different socioeconomic status in Northern Ireland. These may help explain the basis of established socioeconomic differences in obesity risk.  相似文献   
73.
Health consequences of obesity.   总被引:10,自引:0,他引:10  
The recent epidemic of childhood obesity(1) has raised concern because of the possible clinical and public health consequences.(2,)(3) However, there remains a widespread perception among health professionals that childhood obesity is a largely cosmetic problem, with minor clinical effects. No systematic review has yet focused on the diverse array of possible consequences of childhood obesity, though older non-systematic reviews are available.(4,)(5) In addition, no review to date has considered the vast body of evidence on the health impact of childhood obesity which has been published recently. The aim of the present review was therefore to provide a critically appraised, evidence based, summary of the consequences of childhood obesity in the short term (for the child) and longer term (in adulthood).  相似文献   
74.
OBJECTIVE: To evaluate an integrated fellowship in vascular surgery and interventional radiology initiated to train vascular surgeons in endovascular techniques and to train radiology fellows in clinical aspects of vascular diseases. SUMMARY BACKGROUND DATA: The rapid evolution of endovascular techniques for the treatment of vascular diseases requires that vascular surgeons develop proficiency in these techniques and that interventional radiologists develop proficiency in the clinical evaluation and management of patients who are best treated with endovascular techniques. In response to this need the authors initiated an integrated fellowship in vascular surgery and interventional radiology and now report their interim results. METHODS: Since 1999 vascular fellows and radiology fellows performed an identical year-long fellowship in interventional radiology. During the fellowship, vascular surgery and radiology fellows perform both vascular and nonvascular interventional procedures. Both vascular surgery and radiology-based fellows spend one quarter of the year on the vascular service performing endovascular aortic aneurysm repairs and acquiring clinical experience in the vascular surgery inpatient and outpatient services. Vascular surgery fellows then complete an additional year-long fellowship in vascular surgery. To evaluate the type and number of interventional radiology procedures, the authors analyzed records of cases performed by all interventional radiology and vascular surgery fellows from a prospectively maintained database. The attitudes of vascular surgery and interventional radiology faculty and fellows toward the integrated fellowship were surveyed using a formal questionnaire. RESULTS: During the fellowship each fellow performed an average of 1,201 procedures, including 808 vascular procedures (236 diagnostic angiograms, 70 arterial interventions, 59 diagnostic venograms, 475 venous interventions, and 43 hemodialysis graft interventions) and 393 nonvascular procedures. On average fellows performed 20 endovascular aortic aneurysm repairs per year. There was no significant difference between the vascular surgery and radiology fellows in either the spectrum or number of cases performed. Eighty-eight percent (23/26) of the questionnaires were completed and returned. Both interventional radiologists and vascular surgeons strongly supported the integrated fellowship model and favored continuation of the integrated program. Vascular surgery and interventional radiology faculty members wanted additional training in clinical vascular surgery for the radiology-based fellows. With the exception of the radiology fellows there was uniform agreement that vascular surgery fellows benefit from training in nonvascular aspects of interventional radiology. CONCLUSIONS: Integration of vascular surgery and interventional radiology fellowships is feasible and is mutually beneficial to both disciplines. Furthermore, the integrated fellowship provides exceptional training for vascular surgery and interventional radiology fellows in all catheter-based techniques that far exceeds the minimum requirements for credentialing suggested by various professional societies. There is a clear need for cooperation and active involvement on the parts of the American Board of Radiology and the American Board of Surgery and its Vascular Board to create hybrid training programs that meet mutually agreed-on criteria that document sufficient acquisition of both the cognitive and technical skills required to manage patients undergoing endovascular procedures safely and effectively.  相似文献   
75.
76.
77.
This study compared the rates of proliferation and apoptosis of cells within nodules of Dupuytren's disease and nodules from patients that had been injected preoperatively with steroid (Depo-Medrone). It also compared the effects of steroids in apoptosis in cultured Dupuytren's cells and control fibroblasts from palmar fascia and fascia lata. Steroids reduced the rate of fibroblast proliferation and increased the rate of apoptosis of both fibroblasts and inflammatory cells in Dupuytren's tissue. Steroids also produced apoptosis of cultured Dupuytren's cells but not of palmar fascia and fascia lata cells.  相似文献   
78.
Nasopharyngeal carriage of Haemophilus influenzae and Streptococcus pneumoniae was studied in 621 healthy Chinese children and 300 healthy Vietnamese children aged from 2 months to 5 years in Hong Kong. The carriage rate of H, influenzae type b in Vietnamese children was 1.3% (CI 0.04-2.63%); it was zero in Chinese. The carriage rate of non-typable H. influenzae was 5.8% (CI 1.4-7.6%) in Chinese and 65.4% (CI 58.9-69.8%) in Vietnamese. The carriage rates of S. pneumoniae were 10.8% (CI 8.3-13.2%) and 55.7% (CI 50.1-61.3%) in Chinese and Vietnamese children, respectively. Univariate and multivariate logistic regression analyses were performed to search for factors associated with differences in carriage rates of both H. influenzae and S. pneumoniae between Chinese and Vietnamese children. Although older age, smaller living area and parental smoking were associated with higher carriage rates, these could not explain the remarkably low carriage rates of both bacteria in Chinese children.  相似文献   
79.
80.
Transgenic mice with both alleles of the p53 tumor suppressor gene product 'knocked out' by gene targeting are susceptible to early development of tumors, chiefly lymphomas and sarcomas. Compared with the control group, administration of dehydroepiandrosterone (DHEA) at 0.3% of the diet to male p53-deficient mice extended their lifespan by delaying death due to neoplasms (from 105 to 166 days on study, P = 0.002), primarily by suppressing lymphoblastic lymphoma (from 45 to 6% of neoplastic deaths, P = 0.010). Treatment with a synthetic DHEA analog, 16alpha-fluoro-5-androsten-17-one (compound 8354), at 0.15% of the diet also increased lifespan, to 140 days for mice that developed tumors (P = 0.037). The effects of these steroids on lifespan and tumor development did not appear to be strongly related to inhibition of food consumption and weight gain, in that a group pair-fed with control diet to the reduced food consumption of the DHEA-treated group developed and died of the same types of neoplasms at the same rate as the controls fed ad libitum. The chemopreventive effect of these steroids has been proposed to be due to suppression of DNA synthesis by inhibition of glucose 6-phosphate dehydrogenase, the rate-limiting enzyme of the pentose phosphate pathway. Although DHEA and its analog are strong non- competitive inhibitors of this enzyme in vitro, treatment with DHEA did not deplete cellular nucleotide pools in the liver, as would have been predicted. The chemopreventive effect of DHEA in this model may be due to steroid-induced thymic atrophy and suppression of T cell lymphoma, permitting these mice to survive long enough to develop tumors with longer latency.   相似文献   
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