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Chromosomal and microsatellite instability in sporadic gastric cancer   总被引:5,自引:0,他引:5  
BACKGROUND: Gastric cancer can progress through two pathways of genomic instability: chromosomal (CIN) and microsatellite instability (MSI). It is hypothesized that these two pathways are not always independent and that some tumors show overlap between these two mechanisms. METHODS: A total of 98 sporadic gastric cancers were classified based on their MSI status, using microsatellite assay with BAT26. Evidence for CIN was investigated by identifying loss of heterozygosity (LOH) events on chromosome arms, 5q, 10p, 17p, 17q, and 18q, which are regions harboring tumor suppressor genes that are significant in gastric cancer development. RESULTS: Twelve tumors (12%) showed high-frequency MSI (MSI-H). Overall, 43 of the tumors (44%) had at least one LOH event, with most frequent chromosomal losses observed on 10p and 18q (30%, respectively), followed by 5q (21%), 17p (14%), and 17q (12%). Interestingly, overlap was observed between CIN and MSI pathways. Of 43 cancers with LOH events, four (9%) were also MSI-H. It was also found that 48% of cancers without MSI-H had no LOH events identified, comprising a subgroup of tumors that were not representative of either of these two pathways of genomic instability. CONCLUSION: These results suggest that molecular mechanisms of genomic instability are not necessarily independent and may not be fully defined by either the MSI or CIN pathways in sporadic gastric cancers.  相似文献   
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We performed morphological and physiological studies in 43 male patients with alcohol dependence (ALC) who had no other apparent lesions in the upper gastrointestinal tract except atrophic and erosive gastritis. A gastric secretory study in which tetragastrin was used as the stimulant revealed that acid and pepsin secretion was less in ALC patients than in hospital controls (p less than 0.001). Endoscopic biopsy specimens of gastric mucosa from ALC patients revealed that atrophy of the gastric mucosa advanced with age. A strong negative correlation was also found between the secretory capacity of the stomach and the degree of atrophy. Possibly, the interval between recurrent episodes of acute mucosal damage was too short to allow complete healing of mucosal lesions. Failure to regenerate denuded epithelium would result in a decrease in the gastric secretory area. Thus, chronic alcohol abuse seems to be an etiological factor in atrophic gastritis.  相似文献   
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BackgroundThe information on electrocardiographic features of patients with coronavirus disease 2019 (COVID-19) is limited. Our aim was to determine if baseline electrocardiographic features of hospitalized COVID-19 patients are associated with markers of myocardial injury and clinical outcomes.MethodsIn this retrospective, single center cohort study, we included 223 hospitalized patients with laboratory-confirmed COVID-19. Clinical, electrocardiographic and laboratory data were collected and analyzed. Primary composite endpoint of mortality, need for invasive mechanical ventilation, or admission to the intensive care unit was assessed.ResultsForty patients (17.9%) reached the primary composite endpoint. Patients with the primary composite endpoint were more likely to have wide QRS complex (>120 ms) and lateral ST-T segment abnormality. The multivariable Cox regression showed increasing odds of the primary composite endpoint associated with acute respiratory distress syndrome (odds ratio 7.76, 95% CI 2.67–22.59; p < 0.001), acute cardiac injury (odds ratio 3.14, 95% CI 1.26–7.99; p = 0.016), high flow oxygen therapy (odds ratio 2.43, 95% CI 1.05–5.62; p = 0.037) and QRS duration longer than >120 ms (odds ratio 3.62, 95% CI 1.39–9.380; p = 0.008) Patients with a wide QRS complex (>120 ms) had significantly higher median level of troponin T and pro-BNP than those without it. Patients with abnormality of lateral ST-T segment had significantly higher median level of troponin T and pro-BNP than patients without.ConclusionsThe presence of QRS duration longer than 120 ms and lateral ST-T segment abnormality were associated with worse clinical outcomes and higher levels of myocardial injury biomarkers.  相似文献   
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As there is still a shortage of pediatric donor hearts, several techniques have been used to assist pediatric patients to survive until transplantation. VADs provide long‐term support and ability of mobilization for children before a suitable heart becomes available. Several devices such as paracorporeal pumps have been used for this purpose, with acceptable morbidity and mortality rates. However, discharge is not possible, as there is no mobile drive unit for these small‐sized pumps. The possible negative psychosocial impact of long‐term hospitalization, away from home and school, may cause some adjustment problems in the future. In this case series, three pediatric patients that underwent intracorporeal LVAD implantation and returned to school are presented to share clinical experience and also to attract attention to the potential social and psychiatric implications.  相似文献   
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Autism spectrum disorders (ASD) and obsessive-compulsive disorder (OCD) are highly comorbid, precipitating an urgent need to identify evidence-based practices that might be used to address this comorbidity exclusively. The aim of this study was to conduct a review of intervention research and clinical reports to examine the use of cognitive behavioral therapy (CBT) with individuals who have comorbid ASD and OCD. Based on the pre-determined review inclusion criteria, 11 studies were included in the review: three randomized control trials (RCT), one case controlled study, two single subject experimental designs, and five case studies. These studies offer promising data on the use of CBT interventions for individuals with ASD and comorbid OCD as well as for individuals with OCD and comorbid ASD when standard CBT protocol is enhanced with modifications such as parental involvement, increased use of visuals, personalized treatment metaphors, self-monitoring, positive reinforcement, and use of clear language and instructions. Limitations and implications for future research and practice are discussed.  相似文献   
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OBJECTIVE: The purpose of this trial was to determine the spectrum of diseases with fever of unknown origin (FUO) in Turkey. METHODS: A prospective multicenter study of 154 patients with FUO in twelve Turkish tertiary-care hospitals was conducted. RESULTS: The mean age of the patients was 42+/-17 years (range 17-75). Fifty-three (34.4%) had infectious diseases (ID), 47 (30.5%) had non-infectious inflammatory diseases (NIID), 22 (14.3%) had malignant diseases (MD), and eight (5.2%) had miscellaneous diseases (Mi). In 24 (15.6%) of the cases, the reason for high fever could not be determined despite intensive efforts. The most common ID etiologies were tuberculosis (13.6%) and cytomegalovirus (CMV) infection (3.2%). Adult Still's disease was the most common NIID (13.6%) and hematological malignancy was the most common MD (7.8%). In patients with NIID, the mean duration of reaching a definite diagnosis (37+/-23 days) was significantly longer compared to the patients with ID (25+/-12 days) (p=0.007). In patients with MD, the mean duration of fever (51+/-35 days) was longer compared to patients with ID (37+/-38 days) (p=0.052). CONCLUSIONS: Although infection remains the most common cause of FUO, with the highest percentage for tuberculosis, non-infectious etiologies seem to have increased when compared with previous studies.  相似文献   
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