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Some investigators have suggested that preoperative chemotherapy for hepatic colorectal metastases may cause hepatic injury and increase perioperative morbidity and mortality. The objective of the current study was to examine whether treatment with preoperative chemotherapy was associated with hepatic injury of the nontumorous liver and whether such injury, if present, was associated with increased morbidity or mortality after hepatic resection. Two-hundred and twelve eligible patients who underwent hepatic resection for colorectal liver metastases between January 1999 and December 2005 were identified. Data on demographics, clinicopathologic characteristics, and preoperative chemotherapy details were collected and analyzed. The majority of patients received preoperative chemotherapy (n = 153; 72.2%). Chemotherapy consisted of fluoropyrimidine-based regimens: 5-FU monotherapy, 31.6%; irinotecan, 25.9%; and oxaliplatin, 14.6%. Among those patients who received chemotherapy, the type of chemotherapy regimen predicted distinct patterns of liver injury. Oxaliplatin was associated with increased likelihood of grade 3 sinusoidal dilatation (p = 0.017). Steatosis >30% was associated with irinotecan (27.3%) compared with no chemotherapy, 5-FU monotherapy, and oxaliplatin (all p < 0.05). Irinotecan also was associated with steatohepatitis, as two of the three patients with steatohepatitis had received irinotecan preoperatively. Overall, the perioperative complication rate was similar between the no-chemotherapy group (30.5%) and the chemotherapy group (35.3%) (p = 0.79). Preoperative chemotherapy was also not associated with 60-day mortality. In patients with hepatic colorectal metastases, preoperative chemotherapy is associated with hepatic injury in about 20 to 30% of patients. Furthermore, the type of hepatic injury after preoperative chemotherapy was regimen-specific. Presented at the American Hepato-Pancreato-Biliary Association 2006 Annual Meeting, March 11, Miami, Florida.  相似文献   
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OBJECTIVE: Laws that prohibit certain individuals from owning firearms also pertain to ammunition. Whereas retail sales of firearms to criminals are regularly disrupted by instant background checks, sales of ammunition are essentially unchecked and the rate at which criminals acquire ammunition is unknown. This research describes the ammunition market and estimates the rate at which criminals are acquiring ammunition. DESIGN: Criminal background checks conducted on individuals purchasing ammunition in the City of Los Angeles in April and May 2004. SETTING: Los Angeles, CA, USA. SUBJECTS: Ammunition purchasers. MAIN OUTCOME MEASURES: Criminal activity that prohibits one from owning, purchasing, or possessing ammunition. RESULTS: 2.6% (95% CI 1.9% to 3.2%) of ammunition purchasers had a prior felony conviction or another condition that prohibited them from possessing ammunition. During the study period prohibited possessors purchased 10,050 rounds of ammunition in Los Angeles. CONCLUSIONS: These estimates suggest that monitoring ammunition transactions may help reduce the supply of ammunition to criminals and the frequency of injuries from felonious gun assaults. Such a record can also provide information for generating leads on illegal firearm possession.  相似文献   
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Vitamin A (retinol), a fat-soluble vitamin, is an essential nutrient for the normal functioning of the visual system, epithelial cell integrity and growth, immunity, and reproduction. Our group has investigated the effect of high doses of oral vitamin A on early childhood diarrhea in our prospective community-based studies from Northeast Brazil and found a beneficial role in reducing the mean duration but not incidence of diarrheal episodes. In this study, we explored the role of retinol supplementation in intestinal cell lines following Clostridium difficile toxin A (TxA) challenge. C. difficile is the most common anaerobic pathogen borne with antibiotic-borne diarrhea and pseudomembranous colitis. Since retinol is critical for the integrity of tight junctions and to modulate the cell cycle, we have focused on changes in transepithelial electrical resistance (TEER) in Caco-2, a more differentiated intestinal cell line, and on models of cell proliferation, migration and viability in IEC-6 cells, an undifferentiated crypt cell line, following TxA injury. In this model, retinol therapy reduced apoptosis, improved cell migration and proliferation, and prevented the reduction in TEER, following C. difficile TxA challenge in a glutamine-free medium. These results suggest the role of retinol in protecting intestinal epithelial barrier function from C. difficile TxA enterotoxic damage.  相似文献   
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We evaluated anti-Toxoplasma gondii IgM-reactive pregnant women seen at a high-risk pregnancy outpatient clinic. From March 2005 to January 2008 in Paraná, Brazil, pregnant women seen by the Brazilian Public Health System, in any gestational period, who were anti-T. gondii IgM-positive, were followed. Clinical symptoms were noted, and tests performed including IgA, IgG avidity, ultrasonogram, and amniocentesis (PCR/inoculation in mice). Of 75 patients, 8 showed low, 3 intermediate and 31 high IgG avidity. Of those who underwent the avidity test, 31 (70.5%) were in the second trimester of pregnancy. Thirty-two (42.7%) pregnant women received specific treatment. Six received triple combination treatment; in three, tachyzoites were isolated, although only one was PCR-positive, showing changes in the cerebral sonogram, borderline IgA, and the Sabin tetrad. One fetus died, and one non-reactive IgM pregnant woman showed ocular recurrence. The municipality of residence, contact with cats during adulthood, and ingestion of unpasteurized milk were shown to be important risk factors. Congenital toxoplasmosis was observed in a pregnancy referred late for treatment. Follow-up of children born to mothers with diagnosed or suspected acute toxoplasmosis is crucial in the management of the changes that toxoplasmosis may cause.  相似文献   
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