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The paper studies a surface electromyogram (SEMG) decomposition technique suitable for identification of complete motor unit (MU) firing patterns and their motor unit action potentials (MUAPs) during low-level isometric voluntary muscle contractions. The algorithm was based on a correlation matrix of measurements, assumed unsynchronised (uncorrelated) MU firings, exhibited a very low computational complexity and resolved the superimposition of MUAPs. A separation index was defined that identified the time instants of an MU's activation and was eventually used for reconstruction of a complete MU innervation pulse train. In contrast with other decomposition techniques, the proposed approach worked well also when the number of active MUs was slightly underestimated, if the MU firing patterns partly overlapped and if the measurements were noisy. The results on synthetic SEMG show 100% accuracy in the detection of innervation pulses down to a signal-to-noise ratio (SNR) of 10 dB, and 93±4.6% (mean± standard deviation) accuracy with 0 dB additive noise. In the case of real SEMG, recorded with an array of 61 electrodes from biceps brachii of five subjects at 10% maximum voluntary contraction, seven active MUs with a mean firing rate of 14.1 Hz were identified on average.  相似文献   
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Archivum Immunologiae et Therapiae Experimentalis - Sepsis is the most frequent cause of death in noncoronary intensive care units. In the past 10 years, progress has been made in the...  相似文献   
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BACKGROUND AND AIMS: We previously reported that the sole clinicopathological parameters of carcinomas diagnosed in a single institution in 1975 differed from those in patients diagnosed in 1995. The findings might be compatible with the loss of importance of the microsatellite instability of the carcinogenic pathway. MATERIALS AND METHODS: We examined the microsatellite status and selected immunomarkers (Ki-67, p53, BAX) in the archival material from 1975 (n=76) and 1995 (n=105). RESULTS AND CONCLUSION: The distribution of tumors showing no microsatellite instability, low microsatellite instability, and high microsatellite instability in the 2-yearly cohorts was similar (1975: 55.6%, 22.2%, 22.2%; 1995: 60.2%, 20.4%, 19.4%, respectively). The percentage of carcinomas showing microsatellite instability at the APC locus differed significantly (1975: 37.5%; 1995: 21.4%). The typical clinicopathological parameters of carcinomas exhibiting high microsatellite instability were largely shared by the carcinomas demonstrating instability at the APC locus. The carcinomas resected in 1995 more frequently demonstrated high expression of an antiapoptotic protein BAX and a different distribution of their Ki-67 proliferation fraction. The evolution of colorectal carcinoma in Poland also involves qualitative changes, including its genetic background.  相似文献   
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Introduction  

The present study was conducted to assess the value of serum concentration of lipopolysaccharide-binding protein (LBP) in patients with systemic inflammatory response syndrome (SIRS), sepsis and septic shock with respect to its ability to differentiate between infectious and noninfectious etiologies in SIRS and to predict prognosis.  相似文献   
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Introduction  

The aim of this study was to compare the early postoperative kinetics of procalcitonin (PCT) and C-reactive protein (CRP) serum levels in patients undergoing orthotopic liver transplantation (OLTx) with different immunosuppressive regimens.  相似文献   
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OBJECTIVE: To establish whether we might predict the outcome of unstimulated in-vitro fertilization/intracytoplasmic sperm injection (IVF/ICSI) cycles with quantitative indices of perifollicular blood flow assessed with three-dimensional (3D) reconstruction of power Doppler images. METHODS: This prospective study included an analysis of 52 unstimulated cycles. Color and power Doppler ultrasound examinations of a single dominant preovulatory follicle were performed on the day of oocyte pick-up. With 3D reconstruction and processing, quantitative indices were obtained i.e. the percentage of volume showing a flow signal (VFS) inside a 5-mm capsule of perifollicular tissue and the percentage of VFS of each of the three largest vessels in this capsule. These indices as well as pulsed Doppler indices were compared between the groups of cycles with different outcomes using a one-way ANOVA test. RESULTS: In nine cycles no oocyte was retrieved (Group A), in seven cycles no fertilization occurred (Group B) and in 30 cycles no implantation occurred (Group C). Six cycles resulted in pregnancy (Group D). There were no statistically significant differences in pulsed and power Doppler indices between these groups. However, the percentage of VFS in the capsule was higher than average in cycles with implantation (19.22 +/- 16.82 vs. 12.42 +/- 8.89, NS) and the percentage of VFS in the main vessel exhibited lower than average values in cycles with implantation (20.66 +/- 10.05 vs. 39.84 +/- 20.15), but only reached borderline statistical significance (F = 2.457, P = 0.074). CONCLUSION: It can be hypothesized that the follicles containing oocytes able to produce a pregnancy have a distinctive and more uniform perifollicular vascular network.  相似文献   
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Background

It remains unclear into which level the systolic blood pressure (SBP) should be lowered in order to provide the best cardiovascular protection among older people. Hypertension guidelines recommendation on attaining SBP levels <150 mmHg in this population is currently based on experts’ opinion. To clarify this issue, we systematically reviewed and quantified available evidence on the impact of achieving different SBP levels <150 mmHg on various adverse outcomes in subjects aged ≥60 years old receiving antihypertensive drug treatment.

Methods

We searched 8 databases to identify randomized controlled trials (RCTs) and post-hoc analyses or subanalyses of RCTs reporting the effects of attaining different SBP levels <150 mmHg on the risk of stroke, acute myocardial infarction, heart failure, cardiovascular mortality and all-cause mortality in participants aged ≥60 years. We performed random-effects meta-analyses stratified by study design.

Results

Eleven studies (> 33,600 participants) were included. Compared with attaining SBP levels ≥140 mmHg, levels of 130 to <140 mmHg were not associated with lower risk of outcomes in the meta-analysis of RCTs, whereas there was an associated reduction of cardiovascular mortality (RR 0.72, 95% CI 0.59–0.88) and all-cause mortality (RR 0.86, 95% CI 0.75–0.99) in the meta-analysis of post-hoc analyses or subanalyses of RCTs. Limited and conflicting data were available for the SBP levels of <130 mmHg and 140 to <150 mmHg.

Conclusions

Among older people, there is suggestive evidence that achieving SBP levels of 130 to <140 mmHg is associated with lower risks of cardiovascular and all-cause mortality. Future trials are required to confirm these findings and to provide additional evidence regarding the <130 and 140 to <150 mmHg SBP levels.
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