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71.
AIM: To determine whether ischemic preconditioning (IP) affects the development of edematous cerulein-induced pancreatitis and to assess the role of cyclooxygenase-1 (COX-1), COX-2, and heat shock protein 70 (HSP 70) in this process, METHODS: In male Wistar rats, IP was performed by clamping of celiac artery (twice for 5 min at 5-min intervals). Thirty minutes after IP or sham operation, acute pancreatitis was induced by cerulein. Activity of COX-1 or COX-2 was inhibited by resveratrol or rofecoxib, respectively (10 mg/kg). RESULTS: IP significantly reduced pancreatic damage in cerulein-induced pancreatitis as demonstrated by the improvement of pancreas histology, reduction in serum lipase and poly-C ribonuclease activity, and serum concentration of pro-inflammatory interleukin (IL)-lp. Also, IP attenuated the pancreatitis-evoked fall in pancreatic blood flow and pancreatic DNA synthesis. Serum level of anti-inflammatory IL-10 was not affected by IP. Cerulein-induced pancreatitis and IP increased the content of HSP 70 in the pancreas. Maximal increase in HSP 70 was observed when IP was combined with cerulein-induced pancreatitis. Inhibition of COXs, especially COX-2, reduced the protective effect of IP in edematous pancreatitis. CONCLUSION: Our results indicate that IP reduces pancreatic damage in cerulein-induced pancreatitis and this effect, at least in part, depends on the activity of COXs and pancreatic production of HSP 70.  相似文献   
72.
AIM: Epidemiological data show that citizens of small towns and villages have presented worse trends in cardiovascular mortality during the political, social and economic transformation in Poland during past 15 years than citizens of large towns. To try to eliminate these inequalities the Polish 400 Cities Project (P400CP), a large educational and interventional project, was prepared. The project consists of two arms: medical and social interventions. MATERIAL AND METHODS: The main aim of the medical screening intervention in P400CP is to increase detection and control of cardiovascular risk factors in inhabitants of 418 small cities (<8000 inhabitants) and surrounding villages, particularly in men and people of lower education. In 2003 and 2004 the P400CP covered 123 cities. All together, 36 696 subjects aged between 18 and 98 years were examined. In all participants, blood pressure (BP), anthropometric measurements, laboratory tests and questionnaire interviews were performed. The social arm of P400CP is one of multi-level educational intervention. Modern techniques of social psychology and marketing were involved to increase participation in interventions. RESULTS: Only 12.5% of all subjects had normal BP, cholesterol (<190 mg/dl) and glucose (<100 mg/dl in whole capillary blood) levels. During the first screening visit 65.5% of all examined subjects had BP>/=140 mmHg or >/=90 mmHg. The fasting glucose level was increased in 19% of women and 26% of men. Almost two-third of all subjects had a total cholesterol level above the norm. CONCLUSIONS: The prevalence of cardiovascular risk factors in participants of the screening programme P400CP in small towns in Poland was very high. High prevalence and low control of risk factors in participants of the P400CP confirm the decision to target this programme at citizens of small towns and villages.  相似文献   
73.
Dual atrioventricular nodal nonreentrant tachycardia (DAVNNT) is very rarely observed clinically. The first review of this arrhythmia was published in 2011 by Wang, where four types of DAVNNT were described. Our case report presents a phenomenon that has never been published before. We revealed a very specific sequence of double fire phenomenon, 1:1 atrioventricular (AV) conduction and AV block.  相似文献   
74.
Weekly injections with pegylated‐IFNa (PegIFN) combined with daily ribavirin (RBV) are still the standard of care for chronic hepatitis C in most of the world. Sustained virological response (SVR) of 40–50% for patients infected with HCV genotypes (GT) 1 or 4 and 70–90% for genotypes 2–3 are achieved with this regimen. Triple therapy, registered in both the EU and USA, utilizing the first‐generation direct protease inhibitors is able to increase the SVR rates to 75%, but its use is restricted to patients infected with HCV GT1. Additional limitations include challenging dosing schedules, complex treatment algorithms, limited efficacy in patients with previous null response to PegIFN/RBV therapy and additional side effects. There is also an important need for more effective antiviral therapy for difficult‐to‐treat populations with PEG‐IFN intolerance, particularly those with cirrhosis and non‐responders to previous therapies. All‐oral, IFN‐free therapies are an evolutionary step for future anti‐HCV therapies. Initial results of clinical studies conducted during the last year give hope for ‘a pill for HCV’ at least in selected CHC populations. In 2013 several clinical trials of all‐oral anti‐HCV therapies had been completed, first all‐oral combination submitted for registration and some conclusions could be drawn. However, there is not yet a clear direction for IFN‐free therapies in treatment naïve patients or more complex non‐responders.  相似文献   
75.
This work presents the analysis of functional relationships between fraction size of abrasives and geometric parameters of surfaces after rotary cleaning. The influence of an abrasive type on the effectiveness of rotary cleaning of machine parts with complex geometric features was determined as well. The process of mechanical cleaning, using a rotational method, of clutch springs was performed in the proprietary device for rotational cleaning, which was followed by the computer-aided analysis of the obtained results. The research process was carried out using abrasive materials such as grinding stone, sand, basalt, glass, and fine gravel, and the test samples were clutch springs after eight years of operation. Based on calculated three-dimensional (3D) roughness values of the cleaned samples’ surfaces, qualitative classification of abrasives was determined. The most effective material turned out to be fine gravel, while the worst results were related to basalt usage.  相似文献   
76.
77.

Objectives

The aim of the study was to assess the frequency of pyramidal lobe (PL) detected in iodine-131 (I-131) scans of thyroid bed in patients after thyroidectomy for differentiated thyroid cancer (DTC) and to investigate influence of PL on endogenous thyrotropin (TSH) stimulation as well as on the effects of the radio-iodine ablation in one-year follow-up.

Patients and methods

This study was designed as a retrospective analysis of 302 radio-iodine neck scans of patients thyroidectomized due to DTC. The study population was selected from patients with PL detected in thyroid bed scintigraphy. Patients without PL were included to the control group. The study and the control groups did not differ in age, sex of patients, histological type and stage of the DTC.

Results

Pyramidal lobes were found in 30.5% of all patients. Patients in the study group underwent repeat surgery more often than controls without PL. Preablative TSH level in patients with PL was statistically lower than in the control group, in contrast to free thyroid hormones, which were higher in patients with PL. Preablative and postablative TSH-stimulated thyroglobulin (Tg) and antibodies against thyroglobulin (TgAbs) were measured in both groups, and comparison did not reveal differences. Moreover, for the per-patient analysis, sites of uptake in whole body scintigraphy performed 1 year after radio-iodine remnant ablation (RRA) did not differ between the study and the control groups.

Conclusion

Pyramidal lobe decreases endogenous TSH stimulation without impact on radio-iodine therapy outcome in patients with DTC.  相似文献   
78.
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80.
Conventional coronary angiography (CCA) has considerable limitations regarding visualization of distal vessel segments in chronic total occlusion. We assessed the ability of coronary computed tomographic angiography (CCTA) to predict the success of coronary artery bypass grafting (CABG) to the chronically occluded left anterior descending coronary artery (LAD) incompletely visualized on CCA. Thirty symptomatic patients rejected for CABG on the basis of the CCA findings underwent preoperative CCTA before intended transmyocardial laser revascularization. The LAD was explored operatively in all patients, and CABG to the LAD was attempted if the distal vessel was suitable for anastomosis. The procedural outcome of CABG and the 6-month patency of the left internal mammary artery graft at follow-up CCTA were defined as the primary and secondary end point, respectively. The primary and secondary end points were achieved in 80% and 77% of patients, respectively. We found a significant correlation between the intraoperative and computed tomographic measurement of distal LAD diameter (R = 0.428, p = 0.037). On multivariate analysis, the maximum diameter of the distal LAD by CCTA (odds ratio 8.16, p = 0.043) was the only independent correlate of procedural success of CABG. A cutoff value of 1.5 mm for the mean distal LAD diameter predicted left internal mammary artery graft patency with 100% specificity and 83% sensitivity. Successful CABG resulted in significant improvements in angina class and left ventricular function in LAD segments at 6 months of follow-up. In conclusion, CCTA predicted both the procedural and the intermediate outcome of CABG to chronic LAD occlusion with failed visualization on CCA.  相似文献   
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