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Epidemiology suggests that processed meat is associated with colorectal cancer risk, but few experimental studies support this association. We have shown that a model of cured meat made in a pilot workshop promotes preneoplastic lesions, mucin‐depleted foci (MDF) in the colon of rats. This study had two aims: to check if real store‐bought processed meats also promote MDF, and to test if calcium carbonate, which suppresses heme‐induced promotion, can suppress promotion by processed meat. A 14‐day study was done to test the effect of nine purchased cured meats on fecal and urinary biomarkers associated with heme‐induced carcinogenesis promotion. Fecal water from rats given hot dog or fermented raw dry sausage was particularly cytotoxic. These two cured meats were thus given to rats pretreated with 1,2‐dimethylhydrazine, to evaluate their effect on colorectal carcinogenesis. After a 100‐days feeding period, fecal apparent total N‐nitroso compounds (ATNC) were assayed and colons were scored for MDF. Hot dog diet increased fecal ATNC and the number of MDF per colon compared with the no‐meat control diet (3.0 ± 1.7 vs. 1.2 ± 1.4, p < 0.05). In a third study, addition of calcium carbonate (150 µmol/g) to the hot dog diet decreased the number of MDF/colon and fecal ATNC compared with the hot dog diet without calcium carbonate (1.2 ± 1.1 vs. 2.3 ± 1.4, respectively, p < 0.05). This is the first experimental evidence that a widely consumed processed meat promotes colon carcinogenesis in rats. It also shows that dietary prevention of this detrimental effect is possible.  相似文献   
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We present the case of a 52-year-old man, with a history of malignant melanoma, who presented with a testicular lump. Radical orchidectomy confirmed a metastatic malignant melanoma. We discuss salient features of this disease in the light of the published literature.  相似文献   
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Management of femoral diaphyseal fractures in the age group of 6-16 years is controversial. There has been a resurgence worldwide for operative fixation in general and TENS (titanium elastic nailing system) in particular.We performed a retrospective review of pediatric femoral fractures treated by TENS. The data was collected from cases operated between July 2007 and June 2010 at Sohar Hospital, Oman.We had treated 16 children (14 boys and 2 girls) with TENS for femoral shaft fractures. The mean age was 12.5 years (range 7-16 years) and mean hospital stay was 7.6 days (range 4-15 days). All fractures were radio-graphically united at a mean of 7.5 weeks (range 5-10 weeks). The nails were removed in 14 children after a mean of 22 weeks (range 6-38 weeks) postoperatively. At follow-up, we had found leg length discrepancy of 1 cm in one child and 10° of internal rotational deformity in another. No angular deformity had occurred.Titanium elastic nailing seems to be a safe and effective method for the treatment of femoral shaft fractures in children between 7 and 16 years of age.  相似文献   
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Very realistic human-looking robots or computer avatars tend to elicit negative feelings in human observers. This phenomenon is known as the “uncanny valley” response. It is hypothesized that this uncanny feeling is because the realistic synthetic characters elicit the concept of “human,” but fail to live up to it. That is, this failure generates feelings of unease due to character traits falling outside the expected spectrum of everyday social experience. These unsettling emotions are thought to have an evolutionary origin, but tests of this hypothesis have not been forthcoming. To bridge this gap, we presented monkeys with unrealistic and realistic synthetic monkey faces, as well as real monkey faces, and measured whether they preferred looking at one type versus the others (using looking time as a measure of preference). To our surprise, monkey visual behavior fell into the uncanny valley: They looked longer at real faces and unrealistic synthetic faces than at realistic synthetic faces.  相似文献   
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Coronary artery narrowing (CAN), which reduced resting coronary blood flow (BF) by 50%, was induced in 10 conscious dogs and was maintained for 4 hours. Five additional dogs (group 1) with complete coronary artery occlusion were compared to the dogs with CAN. serum isoenzymes of creatine phosphokinase (CK) and latate dehydrogenase (LD) were monitored hourly in all groups. After 36 hours, samples were obtained for regional myocardial BF, quantitative histology, and quantitative ultrastructural (EM) morphology. Six dogs with CAN had small infarcts (MI) of less than 1 gm and persistent myocardial cell injury (group 2). The other four dogs with CAN had only persistent myocardial cell injury by ultrastructural criteria (group 3). Peak serum CK activities in groups 2 and 3 were similar, as were MI sizes calculated from serum CK and myocardial depletion. MB CK was of diagnostic value in group 1 but not in groups 2 and 3. The ratio of LD 1LD 2 had diagnostic value in all three groups. MI size by enzyme estimates was consistently higher than planimetered MI size at autopsy in both groups 1 and 2. All three groups had significant amounts of ultrastructural damage outside of histologically demonstrated MI. These findings suggest that (1) gross and histologic MI size determination of 36 hours after ischemia underestimate extent of damage, and (2) ultrastructural cell changes cause significant release of CK and LD in coronary disease (CAD).  相似文献   
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