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Prolonged excitation of fluorescent probes leads eventually to loss of their capacity to emit light. A decrease in the number of detected photons reduces subsequently the resolving power of a fluorescence microscope. Adverse effects of fluorescence intensity loss on the quality of microscopic images of biological specimens have been recognized, but not determined quantitatively. We propose three human-independent methods of quality determination. These techniques require no reference images and are based on calculation of the actual resolution distance, information entropy, and signal-to-noise ratio (SNR). We apply the three measures to study the effect of photobleaching in cell nuclei stained with propidium iodide (PI) and chromomycin A3 (CA3) and imaged with fluorescence confocal microscopy. We conclude that the relative loss of image quality is smaller than the corresponding decrease in fluorescence intensity. Furthermore, the extent of quality loss is related to the optical properties of the imaging system and the noise characteristics of the detector. We discuss the importance of these findings for optimal registration and compression of biological images.  相似文献   
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Avanafil is a highly selective and potent oral phosphodiesterase type 5 inhibitor. However, its impact on the soluble markers of endothelial function has not been investigated yet. This study was conducted to assess the effect of daily avanafil on the endothelial markers' serum level and erectile function in patients with erectile dysfunction. In this work, we randomly divided 140 males with erectile dysfunction and other diseases commonly associated with endothelial dysfunction like diabetes mellitus, hypertension and dyslipidaemia into two equal groups: treatment group, treated with 50mg daily oral avanafil, and control group, treated with placebo. The International Index of Erectile Function-5 score and the serum levels of nitric oxide, cyclic guanosine monophosphate and endothelin-1 as markers of endothelial function were measured at baseline and after four weeks of treatment in both groups. At the end of treatment period, those randomised to avanafil achieved statistically significant improvement in erectile function, nitric oxide, cyclic guanosine monophosphate and endothelin-1 levels from baseline versus placebo regardless the type and duration of associated comorbidity as well as the duration and severity of erectile dysfunction. These results permitted us to suggest that daily avanafil can improve the impaired endothelial function associated with the erectile dysfunction.  相似文献   
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Background and study aimsBleeding internal haemorrhoids are common and used to be treated surgically with too many complications. Endoscopic therapy is trying to take the lead. Sclerotherapy and rubber band ligation are the candidates to replace surgical therapy especially in patients with liver cirrhosis. The aim of this study was to compare endoscopic injection sclerotherapy (EIS) to endoscopic rubber band ligation (EBL) regarding effectiveness and complications in the treatment of bleeding internal haemorrhoids in Egyptian patients with liver cirrhosis.Patients and methodsOne hundred and twenty adult patients with liver cirrhosis and bleeding internal haemorrhoids were randomised into two equal groups; the first treated with EBL using Saeed multiband ligator, and the second with EIS using either ethanolamine oleate 5% or N-butyl cyanoacrylate. All groups were matched as regards age, sex, Child score and pre-procedure Doppler values. Patients were followed up clinically and with abdominal ultrasound/Doppler for 6 months. Endoscopic and endosonography/Doppler was done before and one month after the procedure. Pre and post-procedure data were recorded and analysed.ResultsBoth techniques were highly effective in the control of bleeding from internal haemorrhoids with a low rebleeding [10% in the EBL group and 13.33% in the EIS group] and recurrence [20% in the EBL group 20% in the EIS group] rates. Child score had a positive correlation with rebleeding and recurrence in EIS group only.Pain score and need for analgesia were significantly higher while patient satisfaction was significantly lower in EIS compared to EBL [p < 0.05]. No significant difference between ethanolamine and cyanoacrylate subgroups was found [p > 0.05].ConclusionsBoth EBL and EIS were effective in the treatment of bleeding internal haemorrhoids in patients with liver cirrhosis. EBL had significantly less pain and higher patient satisfaction than EIS. EBL was also safer in patients with advanced cirrhosis.  相似文献   
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Multiple myeloma is a neoplasm of plasma cells that results in the overproduction of light and heavy chain monoclonal immunoglobulins. The incidence rate increases with age, particularly after 40 years, and is higher in men. To determine the clinical and laboratory characteristics and survival of diagnosed Egyptian multiple myeloma patients admitted to the Haemato-Oncology Department between 2000 and 2010. Records of all patients in whom multiple myeloma was diagnosed at the Kasr Al Aini Hospital between 2000 and 2010 were included in this retrospective study. The mean age of patients was 58.5 years (range, 27–80 years). Fifty-nine percent were males. The majority of patients (73 %) had an immunoglobulin G monoclonal band and 70 % were Kappa chain-positive. Mean overall survival was 37.5 months (range, 1–84 months). Survival analysis was statistically insignificant with respect to age, sex, International Staging System and type of treatment (p?>?0.05). Our records were largely comparable to those reported in Chinese studies but different from those noted in Western and Arabic countries.  相似文献   
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Helicobacter pylori was incriminated as an etiological factor of rosacea. However, there is still controversy about this association. We conducted a comparative study in order to assess the role of H. pylori in rosacea patients who had dyspeptic symptoms. The study included 68 patients and 54 controls. Screening for H. pylori was performed and positive cases were referred for gastric endoscopy. The inflammatory response and bacterial density were evaluated in gastric biopsy. H. pylori vacA alleles, cagA and iceA genotypes were assessed by polymerase chain reaction. We found that 49 rosacea (72%) and 25 controls (46.3%) were infected with H. pylori. Thirty‐one rosacea cases were papulopustular (PPR) while 18 were erythematotelangiectatic (ETR). Gastric ulceration was higher in PPR cases (38.7%) than ETR (11.1%) and controls (12%). A significant inflammatory reaction was observed more in PPR cases (74.2%) compared with 44.4% in ETR (P = 0.04) and 44% in controls (P = 0.02). Analysis of H. pylori genotypes revealed that vacA s1m1 was more identified in PPR cases (54.8%) compared with 22.2% in ETR (P = 0.03) and 16% in controls (P = 0.003). There was a significant elevation of cagA/vacA s1m1 positivity in PPR cases. After the eradication regimen of H. pylori, a significant improvement (P < 0.05) was observed in 15 out of 27 PPR cases (55.6%) compared with three out of 17 ETR (17.6%). We concluded that H. pylori has a significant role in rosacea patients who had dyspeptic symptoms. The PPR type is more influenced by H. pylori and this is regarded as being because of certain virulent strains that increase the inflammatory response in gastric mucosa and also in cutaneous lesions.  相似文献   
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