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A total of 500 individuals from five different regions of Ethiopia were studied. Demographic and clinical data were recorded and serologic tests were carried out to detect antigen and antibody markers of hepatitis B virus, hepatitis A virus, and the delta agent. Data on the economic status, number of rooms per household, number of persons per household, type of water supply, and mode of excreta disposal revealed that the majority of the population surveyed lived with economic hardship, overcrowding and poor hygiene. Only 36 persons gave a past history of jaundice. The mean carrier rate of hepatitis B surface antigen (HBsAg) was 6.2%, the mean overall hepatitis B virus marker prevalence was 42%, and in those over 14 years of age it was 76%. Among those who were positive for HBsAg, there was a tendency for hepatitis B e antigen (HBeAg) to decrease and the corresponding antibody (anti-HBe) to increase with advancing age. No woman more than 15 years of age had demonstrable hepatitis B e antigen in serum. Antibody to hepatitis A virus was detected in 84%. Three positive individuals were found to have antibody to the delta agent.  相似文献   
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Toddler-age nodulocystic acne is a rare disorder for which the etiology remains unknown. We report 2 cases and discuss the safety and efficacy of oral isotretinoin therapy. Oral isotretinoin is safe and effective in treating this condition but requires close monitoring.  相似文献   
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Background: Manipulation and suspension of the superficial musculoaponeurotic system (SMAS) is performed by 74% of rhytidectomy surgeons. Multiple variations in suture techniques are employed in this task, but they have never been evaluated for differences in their ability to withstand stress. Objective: To compare the biomechanical properties of two different suture techniques that are used in SMAS plications during rhytidectomy: a double‐layered running locking (DRL) stitch and multiple horizontal mattress stitches. Methods: Fourteen horizontal mattress plications, in rows of six sutures, and comparable lengths of 16 DRL stitch plications of pig skin samples, were stressed using a tensometer with grip displacement increasing at a constant rate of 0.5 cm/Min. The required force to cause plication failure was recorded for each sample at three suture break points. Results: There was no significant difference between the two groups in the force required to cause the initial suture failure. Unlike the horizontal mattress plication, an initial break seemed to cause minimal to no distortion of the DRL tissue plication. When results were normalized by the initial break forces to account for small variations in tissue properties, the force ratio required to cause a second suture break was significantly larger in the DRL group than in the horizontal mattress technique. This is evidenced by the average second to first break force ratios of 1.62 vs. 1.13 for the DRL and horizontal mattress stitches, respectively, with a P‐value of .60. The mean ratios of third to first break forces for the DRL and horizontal mattress groups were 2.08 and 0.91, respectively, with a P‐value of .08. Conclusion: The DRL stitch requires more force than the horizontal mattress stitch to cause significant failure of tissue plication. This technique may enable plastic surgeons to avoid early revision rhytidectomy due to suture failure, and to create a long‐lasting, youthful cosmetic result.  相似文献   
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The potential utility of tumour-selective 5-fluorouracil treatment using attenuated Salmonella serovar typhimurium recombinant for cytosine deaminase (TAPET-CD) has been documented in experimental settings. The present data demonstrate that in vivo (19)F-magnetic resonance spectroscopy measurements allow the outcome prediction of this prokaryotic-based therapy, demonstrating the necessity of non-invasive real-time imaging techniques for treatment monitoring.  相似文献   
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To increase the potential of attenuated Salmonella as gene delivery vectors for cancer treatment, we developed a hypoxia-inducible promoter system to limit gene expression specifically to the tumor. This approach is envisaged to not only increase tumor specificity, but also to target those cells that are most resistant to conventional therapies. We demonstrate that the exponential growth of the attenuated bacteria is identical under normoxia and hypoxia. A hypoxia-inducible promoter (HIP-1) was created from a portion of the endogenous Salmonella pepT promoter and was shown to drive reporter gene expression under both acute and chronic hypoxia, but not under normoxia. Genetic engineering of the TATA- and FNR-box within HIP-1 allowed fine-tuning of gene induction, resulting in hypoxic induction factors of up to 200-fold. Finally, we demonstrate that HIP-1 can drive hypoxia-mediated gene expression in bacteria which have colonized human tumor xenografts in mouse models. Expression of both GFP and RFP under control of HIP-1 demonstrated an approximately 15-fold increase relative to a constitutive promoter when tumors were made hypoxic. Moreover, the use of a constitutive promoter resulted in reporter gene expression in both tumors and normal tissues, whereas reporter gene expressing using HIP-1 was confined to the tumor.  相似文献   
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