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51.
Heart failure is characterized by activation of the immune system which is strongly associated with disease severity and outcome. We sought to compare the prognostic impact of two established inflammatory markers — interleukin-6 (IL-6) and high-sensitivity C-reactive protein (hsCRP) — in patients with chronic heart failure. In stable, optimally managed outpatients with chronic heart failure, baseline levels of hsCRP and IL-6 were determined. Clinical follow-up was obtained and the rate of events (heart failure related deaths or hospitalizations) were recorded. We included 201 patients (32.7% female, NYHA class II [66.2%] or III [33.8%], mean age 70 years). During a median follow up of 614 (367−761) days, 64 (30.9%) patients experienced an event; those with an event had higher levels of hsCRP (median 2.93 [interquartile range 2.36−8.92] vs 2.23 [1.32−5.77] mmol/l) and IL-6 (7.8 [4.7−10.3] vs 4.3 [2.6−7.9] pg/ml). However, on Cox multivariate analysis, IL-6 but not hsCRP emerged as an independent predictor of prognosis (hazard ratio HRadjusted 2.74, 95% confidence interval 1.17−6.43; P = 0.020). Our findings suggest that IL-6 is a better prognostic predictor than hsCRP in patients with chronic stable heart failure.  相似文献   
52.
Functional disorders of the pelvic floor are a common clinical problem. Diagnosis and treatment of these disorders, which frequently manifest with nonspecific symptoms such as constipation or incontinence, remain difficult. Fluoroscopic x-ray defecography has been shown to aid in detection of functional and morphologic abnormalities of the anorectal region. With the advent of open-configuration magnetic resonance (MR) imaging systems, MR defecography with the patient in a vertical position became possible. MR defecography permits analysis of the anorectal angle, the opening of the anal canal, the function of the puborectal muscle, and the descent of the pelvic floor during defecation. Good demonstration of the rectal wall permits visualization of intussusceptions and rectoceles. Excellent demonstration of the perirectal soft tissues allows assessment of spastic pelvic floor syndrome and descending perineum syndrome and visualization of enteroceles. MR defecography with an open-configuration magnet allows accurate assessment of anorectal morphology and function in relation to surrounding structures without exposing the patient to harmful ionizing radiation.  相似文献   
53.
We studied the variation from the simultaneous contraction of the normal left ventricle (LV). The pattern of the contraction along the LV long axes was assessed on the LV free wall on seven guinea pig hearts in situ with ultra fast video system and epicardial markers by means of the latitude and the size of the areas defined by markers. We found that the contraction occurs as a continuous contraction wave from the apex towards the base, which might yield functional adaptation of these two regions to diastolic and systolic function, respectively.  相似文献   
54.
55.

Background

Helicobacter pylori infection is the main cause of gastric cancer. The disease progression is influenced by the host inflammatory responses, and cytokine single nucleotide polymorphisms (SNPs) may have a role in the course of the disease. The aim of our study was to investigate proinflammatory cytokine polymorphisms, previously associated with the development of gastric cancer, in a Slovenian population.

Patients and methods.

In total 318 patients and controls were selected for the study and divided into three groups: (i) patients with gastric cancer (n = 58), (ii) patients with chronic gastritis (n = 60) and (iii) healthy control group (n = 200). H. pylori infection in patient groups was determined by serology, histology and culture. Four proinflammatory gene polymorphisms were determined (IL-1β, IL-1ra, TNF-α, TLR-4) in all subjects.

Results

We found a statistically significant difference between males and females for the groups (p = 0.025). Odds ratio (OR) for gastric cancer risk for females was 0.557 (95% confidence interval [CI]: 0.233–1.329) and for chronic gastritis 2.073 (95% CI: 1.005–4.277). IL-1B-511*T/T homozygous allele for cancer group had OR = 2.349 (95% CI: 0.583–9.462), heterozygous IL-1B-511*T had OR = 1.470 (95% CI: 0.583–3.709) and heterozygotes in TNF-A-308 genotype for chronic gastritis had OR = 1.402 (95% CI: 0.626–3.139). Other alleles had OR less than 1.

Conclusions

We could not prove association between gastric cancer and chronic gastritis due to H. pylori in any cytokine SNPs studied in Slovenian population. Other SNPs might be responsible besides infection with H. pylori for the progression from atrophy to neoplastic transformation.  相似文献   
56.

Purpose

The aim has been to determine the effect of thermo-mechanical cycling on shear-bond-strength (SBS) of dental porcelain to Co–Cr and Ti-based alloys fabricated by casting, computer-numerical-controlled milling, and selective-laser-melting (SLM).

Methods

Seven groups (n = 22/group) of metal cylinders were fabricated by casting (Co–Cr and commercially pure-cpTi), milling (Co–Cr, cpTi, Ti-6Al-4V) or by SLM (Co–Cr and Ti-6Al-4V) and abraded with airborne-particles. The average surface roughness (Ra) was determined for each group. Dental porcelain was applied and each metal–ceramic combination was divided into two subgroups — stored in deionized water (24-h, 37 °C), or subjected to both thermal (6000-cycles, between 5 and 60 °C) and mechanical cycling (105-cycles, 60 N-load). SBS test-values and failure modes were recorded. Metal–ceramic interfaces were analyzed with a focused-ion-beam/scanning-electron-microscope (FIB/SEM) and energy-dispersive-spectroscopy (EDS). The elastic properties of the respective metal and ceramic materials were evaluated by instrumented-indentation-testing. The oxide thickness on intact Ti-based substrates was measured with Auger-electron-spectroscopy (AES). Data were analyzed using ANOVA, Tukey’s HSD and t-tests (α = 0.05).

Results

The SBS-means differed according to the metal–ceramic combination (p < 0.0005) and to the fatigue conditions (p < 0.0005). The failure modes and interface analyses suggest better porcelain adherence to Co–Cr than to Ti-based alloys. Values of Ra were dependent on the metal substrate (p < 0.0005). Ti-based substrates were not covered with thick oxide layers following digital fabrication.

Conclusions

Ti-based alloys are more susceptible than Co–Cr to reduction of porcelain bond strength following thermo-mechanical cycling. The porcelain bond strength to Ti-based alloys is affected by the applied metal processing technology.  相似文献   
57.
58.
AIMS: The aim of our study was to investigate the accuracy of 64-slice computed tomography (CT) for assessing haemodynamically significant stenoses of coronary arteries. METHODS AND RESULTS: CT angiography was performed in 67 patients (50 male, 17 female; mean age 60.1+/-10.5 years) with suspected coronary artery disease and compared with invasive coronary angiography. All vessels > or =1.5 mm were considered for the assessment of significant coronary artery stenosis (diameter reduction >50%). Forty-seven patients were identified as having significant coronary stenoses on invasive angiography with 18% (176/1005) affected segments. None of the coronary segments needed to be excluded from analysis. CT correctly identified all 20 patients having no significant stenosis on invasive angiography. Overall sensitivity for classifying stenoses was 94%, specificity was 97%, positive predictive value was 87%, and negative predictive value was 99%. CONCLUSION: Sixty-four-slice CT provides a high diagnostic accuracy in assessing coronary artery stenoses.  相似文献   
59.
The aim of the study was to define the relevance of deletions and duplications within the DAZ gene cluster to male factor infertility in a population of 90 infertile men and a control of 50 fertile men using real-time polymerase chain reaction (PCR). We conclude that partial deletions of the DAZ genes are associated with oligozoospermia but not with azoospermia; however, an increased number of DAZ genes does not seem to be a statistically significant risk factor for spermatogenic failure.  相似文献   
60.
In the present study, we quantitatively described and compared lower extremity neuromuscular patterns during level cycling (LC), 10 and 20% uphill cycling (UC). We hypothesized that both the timing and intensity of activity of selected lower extremity muscles will differ between steep (but not moderate slope) UC condition and LC. Twelve trained mountain bikers performed an experimental test with three different cycling conditions (level, 10% slope and 20% slope) with EMG monitoring of eight lower extremity muscles. Significant changes (p < 0.05) in muscle activation timing during 20% UC compared to LC (15° later onset and 39° earlier offset) were observed in m. rectus femoris (RF). Range of activity during 20% UC compared to LC was also significantly (p < 0.05) modified in m. vastus medialis, m. vastus lateralis (8° and 5° shorter) and m. biceps femoris (BF; 17° longer). Furthermore, a reduction of EMG activity level was observed for RF and m. tibialis anterior (TA) during 20% UC compared to LC (25 and 19%; p < 0.05), while the opposite effect was observed for m. gluteus maximus (GM; 12%; p < 0.05). Peak cross-correlation coefficients in all cycling conditions for all muscles were high (all coefficients ≥ 0.83). We have shown that altered body orientation during steep, but not moderate, slope UC significantly modified the timing and intensity of several lower extremity muscles, the most affected being those that cross the hip joint and TA. The observed modifications in neuromuscular patterns during 20% UC could have a significant effect on lower extremity joint kinetics and cycling efficiency.  相似文献   
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