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81.
Changes of lymphatic system, vascular disease during pulmonary hypertension or aneurysms are very often considered to be a cause of wide pulmonary hilus. However, we should remember developmental anomaly of pulmonary artery, too. We present a case of a patient hospitalized very often due to necessity of diagnostic wide, polycyclic pulmonary hilus. Only digital subtraction angiography allowed us to know the reason of wide pulmonary hilus as the developmental anomaly of pulmonary artery.  相似文献   
82.
Aim: The objective of this study was to examine the relationship between TGF-beta expression in steatotic liver and the stage and yearly progression rate of fibrosis in chronic hepatitis C (CHC) patients. Methods: We examined 44 CHC fatty liver patients, using 76 non-steatotic CHC patients as controls. The stage of hepatic fibrosis was assessed on a score scale. TGF-beta expression was determined with the use of monoclonal serum and the ABC three-step method. Results: We demonstrated a positive correlation of steatosis with the stage of fibrosis (P < 0.05). No relationship of thiskind was found with the yearly progression rate of fibrosis (P > 0.09). In steatotic biopsies, TGF-beta expression index in portal spaces and lobules was found to be higher as compared to TGF-beta expression in biopsies without steatosis (P < 0.05). Conclusion: In CHC patients steatosis induces the development of fibrosis by elevating the hepatic expression of TGF-beta.  相似文献   
83.
BACKGROUND AND AIMS: We previously reported that the sole clinicopathological parameters of carcinomas diagnosed in a single institution in 1975 differed from those in patients diagnosed in 1995. The findings might be compatible with the loss of importance of the microsatellite instability of the carcinogenic pathway. MATERIALS AND METHODS: We examined the microsatellite status and selected immunomarkers (Ki-67, p53, BAX) in the archival material from 1975 (n=76) and 1995 (n=105). RESULTS AND CONCLUSION: The distribution of tumors showing no microsatellite instability, low microsatellite instability, and high microsatellite instability in the 2-yearly cohorts was similar (1975: 55.6%, 22.2%, 22.2%; 1995: 60.2%, 20.4%, 19.4%, respectively). The percentage of carcinomas showing microsatellite instability at the APC locus differed significantly (1975: 37.5%; 1995: 21.4%). The typical clinicopathological parameters of carcinomas exhibiting high microsatellite instability were largely shared by the carcinomas demonstrating instability at the APC locus. The carcinomas resected in 1995 more frequently demonstrated high expression of an antiapoptotic protein BAX and a different distribution of their Ki-67 proliferation fraction. The evolution of colorectal carcinoma in Poland also involves qualitative changes, including its genetic background.  相似文献   
84.
BACKGROUND: Although Helicobacter pylori is a significant etiologic factor of peptic ulcer disease, it remains unknown why ulcers develop only in the minority of infected individuals. AIM: The aim of this cross-sectional study was to evaluate the association between the presence of duodenal ulcer in H. pylori-infected patients and different risk factors. METHODS: A total of 122 H. pylori-infected patients were enrolled; 79 had duodenal ulcer and 43 gastritis. Univariate analysis was conducted using either Fisher's exact test or exact Cochrane-Armitage trend test. In multivariate analysis the logistic model was used. RESULTS: Univariate analysis indicated six factors (male sex, smoking, antral H. pylori density, CAGA presence in antrum, and VACA s1a presence in antrum and corpus). Four factors (sex, smoking-alcohol index, H. pylori density index, and CAGA index) were found to be significant in multivariate analysis. The best model predicting duodenal ulcer included male sex, smoking, presence of H. PYLORI on histopathology in antrum and CAGA presence in corpus. CONCLUSION: Although several risk factors were significantly associated with duodenal ulcer, we failed in the identification of either a single risk factor or a set of factors that can unequivocally differentiate patients with ulcer from those with gastritis.  相似文献   
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86.
Arrhythmogenic right ventricular cardiomyopathy (ARVC) is an inheritant disease with an autosomal dominant mode of transmission with incomplete penetrance and variable expression. Linkage analysis in affected families succeeds in identifying 9 loci determining 9 subtypes of the disease. Genotype phenotype correlation is unclear and the influence of various environmental factors is discussed. OBJECTIVES: Genotype phenotype correlation in 2 pairs of monozygotic twins with ARVC and the role of environmental factors are analyzed. PATIENTS AND METHODS: Among 40 pts with ARVC and their 195 relatives there were 2 pairs of monozygotic twins: brothers, age 47 y; and sisters, age 48 y. History, ECG, Holter monitoring, 2D and Doppler Echo, and MRI were analyzed. RESULTS: Twin brothers: ARVC was diagnosed in the proband after the episode of VT with LBBB morphology (enlarged right ventricle, focal hypokinesia of apex, MR evidence of adipose tissue in RV wall). Identical morphology of RV was seen in asymptomatic twin brother. The patient presenting arrhythmia has been rowing for 4 years. Twin sisters: diagnosis was done during family screening. Both were asymptomatic. RV morphology typical for ARVC was found discrete in one of them (bulges adipose tissue in the RV apex); the latter showed changes suggesting RV abnormality (mild segmental dilatation of infundibulum, adipose tissue in a free wall of the RV). No differences in previous viral infections and sports involvement were observed. CONCLUSIONS: 1. Clinical picture of ARVC in monozygotic twins is not identical. 2. Strenuous effort may be a factor triggering the arrhythmia in pts with ARVC.  相似文献   
87.
There are many places on the earth, where natural background radiation exposures are elevated significantly above about 2.5 mSv/year. The studies of health effects on populations living in such places are crucially important for understanding the impact of low doses of ionizing radiation. This article critically reviews some recent representative literature that addresses the likelihood of radiation-induced cancer and early childhood death in regions with high natural background radiation. The comparative and Bayesian analysis of the published data shows that the linear no-threshold hypothesis does not likely explain the results of these recent studies, whereas they favor the model of threshold or hormesis. Neither cancers nor early childhood deaths positively correlate with dose rates in regions with elevated natural background radiation.  相似文献   
88.
Acute coronary syndromes (ACS) without persistent ST-segment elevation are the main cause of hospitalization, morbidity and mortality. The objective of this study was to compare clinical and angiographic parameters as well as in-hospital results of treating 307 consecutive patients with ACS without persistent ST-segment elevation with either PCI or CABG. Inclusion criteria were: rest angina within the last 24 hours, ST-segment depression (> 0.5 mm), T-wave inversion (> 1 mm) in at least two leads, positive serum cardiac markers. PCI was performed in 75.9% of patients and 24.1% of patients underwent CABG. Both groups did not differ as to age, sex, history of diabetes, arterial hypertension, heart failure, smoking and ejection fraction. Positive troponin was significantly more frequent in the PCI group. 51% of PCI patients and 80% of CABG patients had complete revascularization (p = 0.00001). Independent predictors of in-hospital death in the CABG group were: inability to determine culprit vessel during coronary angiography due to lesions' severity (OR 13.65; 95% CI 9.40-15.20; p = 0.007) and heart failure (OR 15.58; 95% CI 12.29-18.01; p = 0.003). In the PCI group these independent predictors were: Braunwald's IIIC unstable angina (OR 5.48; 95% CI 3.10-7.17; p = 0.04) and diabetes (OR 2.22; 95% CI 1.07-3.90; p = 0.003). In-hospital mortality rate was significantly higher in the CABG group (8.1% vs 1.7% p < 0.01). Patients with multivessel coronary artery disease and ACS without ST-segment elevation treated with PCI have better in-hospital outcome than patients assigned to CABG, but the rate of complete revascularization is lower.  相似文献   
89.
Background : How tissue patterns form in development and regeneration is a fundamental issue remaining to be fully understood. The integument often forms repetitive units in space (periodic patterning) and time (cyclic renewal), such as feathers and hairs. Integument patterns are visible and experimentally manipulatable, helping us reveal pattern formative processes. Variability is seen in regional phenotypic specificities and temporal cycling at different physiological stages. Results: Here we show some cellular/molecular bases revealed by analyzing integument patterns. (1) Localized cellular activity (proliferation, rearrangement, apoptosis, differentiation) transforms prototypic organ primordia into specific shapes. Combinatorial positioning of different localized activity zones generates diverse and complex organ forms. (2) Competitive equilibrium between activators and inhibitors regulates stem cells through cyclic quiescence and activation. Conclusions: Dynamic interactions between stem cells and their adjacent niche regulate regenerative behavior, modulated by multi‐layers of macro‐environmental factors (dermis, body hormone status, and external environment). Genomics studies may reveal how positional information of localized cellular activity is stored. In vivo skin imaging and lineage tracing unveils new insights into stem cell plasticity. Principles of self‐assembly obtained from the integumentary organ model can be applied to help restore damaged patterns during regenerative wound healing and for tissue engineering to rebuild tissues. Developmental Dynamics 244:905–920, 2015. © 2015 Wiley Periodicals, Inc.  相似文献   
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