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Many time series studies have found that individuals with primary cardiac conditions were susceptible to the adverse effects associated with increased ambient particle levels. However, the mechanism(s) of these associations is not yet understood. In this study, we evaluate whether individuals with nonrespiratory primary causes of death who also had contributing respiratory causes listed on their death certificates were more affected by air pollution, as compared with those not having contributing respiratory conditions. Short-term associations between ambient particulate matter (10 microm or less in aerodynamic diameter) and mortality were modeled in New York City for the years 1985-1994. It was observed that among those 75 years or more, those with contributing respiratory disease had higher relative risks (95% confidence intervals) calculated per interquartile range, as compared with those without contributing respiratory disease for both circulatory deaths (relative risk = 1.066 [1.027-1.106] versus 1.022 [1.008-1.035]) and cancer deaths (relative risk = 1.129 [1.041-1.225] versus 1.025 [1.000-1.050]). However, this pattern of association was not observed for those who were less than 75 years old. The results of this study suggest that past studies may have underestimated the role of respiratory disease in pollution-mortality associations, especially among older adults.  相似文献   
95.
Mineralized tissue is vital to many characteristic adaptive phenotypes in vertebrates. Three primary tissues, enamel (enameloid), dentin, and bone, are found in the body armor of ancient agnathans and mammalian teeth, suggesting that these two organs are homologous. Mammalian enamel forms on enamel-specific proteins such as amelogenin, whereas dentin and bone form on collagen and many acidic proteins, such as SPP1, coordinately regulate their mineralization. We previously reported that genes for three major enamel matrix proteins, five proteins necessary for dentin and bone formation, and milk caseins and salivary proteins arose from a single ancestor by tandem gene duplications and form the secretory calcium-binding phosphoprotein (SCPP) family. Gene structure and protein characteristics show that SCPP genes arose from the 5' region of ancestral sparcl1 (SPARC-like 1). Phylogenetic analysis on SPARC and SPARCL1 suggests that the SCPP genes arose after the divergence of cartilaginous fish and bony fish, implying that early vertebrate mineralization did not use SCPPs and that SPARC may be critical for initial mineralization. Consistent with this inference, we identified SPP1 in a teleost genome but failed to find any genes orthologous to mammalian enamel proteins. Based on these observations, we suggest a scenario for the evolution of vertebrate tissue mineralization, in which body armor initially formed on dermal collagen, which acted as a reinforcement of dermis. We also suggest that mammalian enamel is distinct from fish enameloid. Their similar nature as a hard structural overlay on exoskeleton and teeth is because of convergent evolution.  相似文献   
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We report a rare case of pulmonary lymphomatoid granulomatosis radiologically mimicking interstitial pneumonia. A 57-year-old man was admitted to our hospital because of chest bilateral reticular shadow with sustained cough and breathlessness for 10 years. Chest CT scans showed multiple ground-glass opacities, traction bronchiectasis and cystic change in both lungs, in addition to hilar and mediastinal lymphadenopathy. A histopathologically diagnosis of pulmonary lymphomatoid granulomatosis (angiocentric immunoproliferative lesion, grade 1) was made by thoracoscopic lung biopsy. In this case, serological and immunohistochemical analyses did not show Epstein-Barr virus infection. No clinical or radiological deterioration has been observed thereafter despite no medication.  相似文献   
98.
An easy and simple method for constructing a urinary diversion in patients undergoing pelvic exenteration for advanced rectal cancer is described. This procedure features double-barreled colostomy with a segment of the sigmoid colon 8 to 10 cm distal to the stoma as a urinary conduit.Read at the meeting of the Japanese Research Society for Cancer of the Colon and Rectum, Tokyo, Japan, July 29, 1994.  相似文献   
99.
BACKGROUND AND AIM: Balloon-occluded retrograde transvenous obliteration (B-RTO) is a novel therapeutic method for the treatment of large gastric fundal varices with spontaneous splenorenal shunt (SRS). However, the effects of B-RTO on liver function remain unknown. METHODS: Fourteen patients with portal hypertension and gastric varices with SRS were studied, consisting of four patients with acute bleeding, five with high-risk varices, and five with refractory portosystemic encephalopathy. Hepatic venous catheterization was performed to evaluate hepatic blood flow and liver function using the continuous indocyanine green (ICG) infusion method. To assess the metabolic activity of the hepatocyte, the intrinsic clearance of ICG was calculated. In all patients, endoscopic study was performed before and 1 week and 1 month after the B-RTO, and followed every 6 months thereafter. After baseline measurements, B-RTO was performed. Four weeks after the B-RTO, the same catheter measurements were repeated. RESULTS: The B-RTO was successful in all patients. Contrast-enhanced computed tomography showed complete obliteration of the SRS prior to the follow-up measurements. Endoscopic eradication of the fundal varices was obtained 6 months after B-RTO in all patients and encephalopathy was improved within 1 week after B-RTO. Following the B-RTO, hepatic blood flow (441 +/- 214 vs 668 +/- 299 mL/min, P < 0.0001) and the intrinsic clearance of ICG (233 +/- 123 vs 285 +/- 148 mL/min, P < 0.05) were significantly increased. Furthermore, intrahepatic resistance decreased after the B-RTO (P < 0.005). CONCLUSION: From short-term assessment, B-RTO increases hepatic blood flow and improves the metabolic activity of the liver in patients with portal hypertension.  相似文献   
100.
The risk allele of a single nucleotide polymorphism (SNP) rs2294008 in the Prostate stem cell antigen (PSCA) gene is strongly associated with gastric cancer. Although the Kyoto classification score is believed to be an indicator of gastric cancer risk, it lacks supporting genetic evidence. We investigated the effect of this risk allele of PSCA SNP on the Kyoto score. Participants without a history of gastric cancer or Helicobacter pylori (H. pylori) eradication underwent esophagogastroduodenoscopy, H. pylori evaluation, and SNP genotyping. The Kyoto score is the sum of scores obtained from endoscopy-based atrophy, intestinal metaplasia, enlarged folds, nodularity, and diffuse redness. The Kyoto score is novel in the light of scoring for gastritis. A total of 323 patients were enrolled (number of individuals with genotype CC: 52; CT: 140; TT: 131, average age: 50.1 years, male: 50.8%). The patient baseline characteristics including age, sex, body mass index, smoking, drinking, family history of gastric cancer, and H. pylori status had no association with PSCA SNP. The Kyoto score was higher in T (CT or TT genotype; risk allele) carriers than in CC carriers. Atrophy, enlarged folds, and diffuse redness scores were higher in T allele carriers (risk allele) than in CC genotype individuals. In multivariate analysis, the Kyoto score was independently associated with PSCA SNP (OR: 1.30, p = 0.012). Thus, the Kyoto score was associated with a genetic predisposition.  相似文献   
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