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21.
22.

Background/Aim:

The aim of this study was to investigate the effects of celiac disease on cardiac functions using tissue Doppler echocardiography (TDE).

Patients and Methods:

The study included 30 patients with celiac disease (CD) and 30 healthy volunteers. Echocardiographic examinations were assessed by conventional echocardiography and tissue Doppler imaging. The peak systolic velocity (S''m), early diastolic myocardial peak velocity (E''m), late diastolic myocardial peak velocity (A''m), E''m/A''m ratio, myocardial precontraction time (PCT''m), myocardial contraction time (CT''m), and myocardial isovolumetric relaxation time (IVRT''m), E to E''m ratio were measured.

Results:

In pulsed wave Doppler echocardiography, mitral late diastolic flow (A) velocity and E to E''m ratio were significantly higher (P = 0.02 and P = 0,017), E/A ratio was significantly lower (P = 0.008) and IVRT was significantly prolonged (P = 0.014) in patients with CD. In TDE, S''m, E''m, and E''m/A''m ratio were significantly lower, IVRT''m was longer (P = 0.009) from septal mitral annulus and S''m, E''m, E''m/A''m ratio were significantly lower, PCT''m, PCT/ET ratio, IVRT''m were longer, and MPI was higher from lateral mitral annulus in celiac group than controls.

Conclusion:

Our study confirms that patients with CD have impaired diastolic function. More importantly, we also demonstrated an impairment of myocardial systolic function in patients with CD by TDE. We recommend using TDE in addition to conventional echocardiography parameters for the cardiovascular risk assessment of patients with CD.  相似文献   
23.
Levosimendan enhances cardiac contractility by increasing myocyte sensitivity to calcium, and induces vasodilatation. Although studies have evaluated the efficacy of levosimendan in heart failure, it is not clear whether it might produce functional influence on platelet response. In this study, the effect of levosimendan on platelet aggregation was investigated. Platelet function tests were performed in 12 healthy male volunteers. Three concentrations of levosimendan solution were prepared that would result in 10, 25, and 45 ng/ml levosimendan concentrations in the blood similar to that observed after clinical therapeutic intravenous application of 0.05-0.1 microg/kg/min. Each concentration of levosimendan solution and a control diluent without levosimendan were incubated with whole blood at 37 degrees C. After incubation for 15 min, aggregation responses were evaluated with adenosine diphosphate (ADP) (5 and 10 microM) and collagen (2 and 5 microg/ml) in platelet-rich plasma. Preincubation with all dilutions of levosimendan inhibited aggregation of platelets induced by ADP and collagen significantly. Levosimendan also inhibited significantly the secondary wave of platelet aggregation induced by ADP. The results showed that there was a relationship between levosimendan concentration and inhibition of platelet aggregation. In conclusion, this study with an in vitro model showed that levosimendan had a significant inhibitory effect on platelets in clinically relevant doses.  相似文献   
24.
25.

Background/Aims:

There are a limited number of studies including the impact of antiplatelet drugs use on hospital outcomes for nonvariceal upper gastrointestinal bleeding. The aim of this study was to determine the effect of anti-aggregant, anti-coagulant and non-steroidal anti-inflammatory drugs upon hospital outcomes in patients with peptic ulcer bleeding.

Materials and Methods:

The patients under treatment with antiaggregant, anticoagulant or non-steroidal anti-inflammatory drugs were categorized as exposed group (n = 118) and the patients who were not taking any of these drugs were categorized as non-exposed group (n = 81). We analyzed the data of drug intake, comorbid disease, blood transfusion, duration of hospital stay, Blatchford/total Rockall score and diagnosis of patients.

Results:

In total, 199 patients were included. Of these 59.3% (exposed group) were taking drugs. The patients in exposed group were significantly older than those in non-exposed group (62.9 ± 17.3 years; 55.5 ± 19.3 years, P = 0.005, respectively). Mean number of red blood cell units transfused (2.21 ± 1.51; 2.05 ± 1.87, P = 0.5), duration of hospital stay (3.46 ± 2.80 days; 3.20 ± 2.30 days, P = 0.532) and gastric ulcer rate (33% vs 23.4%, P = 0.172) were higher in exposed group than in non-exposed group but the differences were not statistically significant. Total Rockall and Blatchford scores of the patients were significantly higher in exposed group than in non-exposed group (3.46 ± 1.72 vs 2.94 ± 1.87, P = 0.045; 10.29 ± 3.15 vs 9.31 ± 3.40, P = 0.038).

Conclusıon:

Our study has shown that anticoagulants, antiaggregants and nonsteroidal anti-inflammatory drugs do not effect duration of hospital stay, red blood cell transfusion requirement and rebleeding for peptic ulcer bleeding.  相似文献   
26.
Conclusion: IBCT technique should be preferred owing to its high graft survival rate and ABG gain. While no significant difference was found in middle ear pressures between ears that underwent IBCT and normal ears, compliance values were found to be decreased in patients undergoing IBCT. However, the lack of correlation between ABG gain and compliance values indicated that compliance increase had no effect on post-operative ABG results. Objective: The aim of the present study was to compare tympanometric and audiological parameters in patients undergoing inlay butterfly cartilage tympanoplasty (IBCT) with their normal ears and to determine their difference with normal ear tympanometric parameters. Methods: Overall, 25 patients that underwent an operation between August 2010–May 2014 were included in the present study. In 13 of these patients, the ear that did not undergo operation was normal. 0.5, 1, 2, 4?kHz pure sound average values, tympanometric measurements and compliance values of normal and operated ears were compared. Results: The graft survival rate in patients was found to be 92%. Mean pre-operative air–bone gap (ABG) was 16.4?±?5.4 in patients, while mean post-operative ABG was 10.9?±?5.8, with a statistically significant difference (p?=?0.001) While there was no significant difference between operated and normal ears of patients in terms of middle ear pressure (0.441), compliance values were significantly higher in normal ears than those in operated ears (0.032). When post-operative ABG gain was compared with compliance values, no significant correlation was found between ABG gain and compliance measurements (r?=??0.025 and p?=?0.936).  相似文献   
27.
28.
Studies of visual function in behaving subjects require that stimuli be positioned reliably on the retina in the presence of eye movements. Fixational eye movements scatter stimuli about the retina, inflating estimates of receptive field dimensions, reducing estimates of peak responses, and blurring maps of receptive field subregions. Scleral search coils are frequently used to measure eye position, but their utility for correcting the effects of fixational eye movements on receptive field maps has been questioned. Using eye coils sutured to the sclera and preamplifiers configured to minimize cable artifacts, we reexamined this issue in two rhesus monkeys. During repeated fixation trials, the eye position signal was used to adjust the stimulus position, compensating for eye movements and correcting the stimulus position to place it at the desired location on the retina. Estimates of response magnitudes and receptive field characteristics in V1 and in LGN were obtained in both compensated and uncompensated conditions. Receptive fields were narrower, with steeper borders, and response amplitudes were higher when eye movement compensation was used. In sum, compensating for eye movements facilitated more precise definition of the receptive field. We also monitored horizontal vergence over long sequences of fixation trials and found the variability to be low, as expected for this precise behavior. Our results imply that eye coil signals can be highly accurate and useful for optimizing visual physiology when rigorous precautions are observed.  相似文献   
29.
International Urology and Nephrology - In this study, we aimed to investigate the effect of paricalcitol and calcitriol usage on vitamin D receptor (VDR) contents of CD8+?,...  相似文献   
30.
Context: Scorzonera L. species (Asteraceae) are edible and as medicinal plants are used for various purposed in folk medicine.

Objective: The methanol extracts of the aerial parts and roots from 27 Scorzonera taxa were investigated for their possible neurobiological effects.

Materials and methods: Inhibitory potential of the Scorzonera species was tested against acetylcholinesterase (AChE), butyrylcholinesterase (BChE), and tyrosinase (TYRO) at 100?µg?mL?1 using ELISA microtiter assay. Antioxidant activity of the extracts was tested with radical scavenging activity, metal-chelation capacity, ferric- (FRAP), and phosphomolibdenum-reducing antioxidant power (PRAP) assays. Chlorogenic acid, hyperoside, rutin, and scorzotomentosin-4-O-β-glucoside were also screened in the same manner. Total phenol and flavonoid quantification in the extracts were determined spectrophotometrically.

Results: The aerial parts of Scorzonera pisidica (40.25?±?0.74%) and chlorogenic acid (46.97?±?0.82%) displayed the highest TYRO inhibition, while the remaining samples showed only trivial inhibition against cholinesterases (2.08?±?1.35%–25.32?±?1.37%). The same extract of S. pisidica was revealed to be the most potent in scavenging of all three radicals and FRAP assay.

Discussion and conclusion: Out of 27 taxa, S. pisidica, in particular, may deserve further investigation for its neuroprotective potential.  相似文献   
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