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31.

Introduction

Thrombotic and inflammatory mechanisms are involved in the pathophysiology of acute coronary syndrome (ACS). The aim of the study was the evaluation of inflammation (white blood cells count/WBC, C-reactive protein/CRP, interleukin-6/IL-6) and platelet (platelet count/PLT, mean platelet volume/MPV, large platelet/LPLT, beta-thromboglobulin/β-TG) biomarkers in the groups of ACS patients depending on the severity of signs and symptoms and compared to controls without coronary artery disease.

Materials and methods

The study group included 93 patients categorized into 3 subgroups depending on the severity of signs and symptoms of ACS. PLT, MPV, LPLT, and WBC were determined on hematological analyzer, IL-6 and β-TG were measured using the ELISA method.

Results

In the whole group of ACS patients WBC, CRP, IL-6, MPV, and β-TG were significantly higher as compared to controls. Analyzing the inflammation and platelet biomarkers depending on the severity of signs and symptoms in comparison to controls, statistically significant differences for above-mentioned parameters were also found. There were no significant differences between the advancement of coronary artery changes and inflammation as well as platelet parameters, except for CRP concentrations. The AUCs for all inflammation parameters tested were similar, however the highest AUCs showed WBC and CRP. Among platelet parameters the highest AUC revealed β-TG.

Conclusion

Markers of inflammation and platelet activation may be associated to myocardial ischemia and myocardial injury. WBC, CRP and IL-6 as inflammation parameters and MPV and β-TG as platelet biomarkers may be useful indicators of the presence of coronary artery disease.  相似文献   
32.

Background and objective

One of the important applications of non-invasive respiration monitoring using ECG signal is the detection of obstructive sleep apnea (OSA). ECG-derived respiratory (EDR) signals, contribute to useful information about apnea occurrence. In this paper, two EDR extraction methods are proposed, and their application in automatic OSA detection using single-lead ECG is investigated.

Methods

EDR signals are extracted based on new respiration-related features in ECG beats morphology, such as ECG variance (EDRVar) and phase space reconstruction area (EDRPSR). After evaluating the EDRs by comparing them to a reference respiratory signal, they are used in an automatic OSA detection application. Fantasia and Apnea-ECG database from PhysioNet are used for EDRs assessments and OSA detection, respectively. The final performance of our OSA detection is tested on an independent test data which is also compared with results of other techniques in the literature.

Results

The extracted EDRs, EDRVar and EDRPSR show correlations of 72% and 70% with reference respiration, which outperform the other state-of-the-art EDR methods. After feature extraction from EDRs and RR intervals series, the combination of RR and EDRPSR feature sets achieved 100% accuracy in subject-based apnea detection on independent test data, and also minute-based apnea detection is done with accuracy, sensitivity and specificity of 90.9%, 89.6% and 91.8%, which is better than other automatic algorithms in the literature.

Conclusions

Our OSA detection system using EDRs features yields better independent test results compared with other state-of-the-art automatic apnea detection methods. The results indicate that ECG-based OSA detection system can classify OSA events with high accuracy and suggest a promising, non-invasive and efficient method for apnea detection.  相似文献   
33.
This study was designed to investigate the alterations in thiobarbituric acid reactants (TBA-reactants) and enzymatic and nonenzymatic antioxidant levels induced by dexamethasone (Dex) in heart and kidney and to find out whether these alterations induced by Dex and its hypertensive effect had any role in the maintenance of hypertension in this model. Administration of dexamethasone induced severe loss of body weight, significant increase in heart and kidney weights and also marked electrocardiographic changes. The protein content in heart and kidney increased significantly during Dex administration and returned to near normalcy after withdrawal. Total activity of lactate dehydrogenase showed a significant increase in heart till day 8 of treatment, whereas in serum, it exhibited a significant decrease. The activity of CK in heart showed an increase till day 8 of treatment and approached normalcy thereafter. In serum, CK exhibited a decrease till day 8, remaining insignificant thereafter. CKMB in heart showed an insignificant increase initially, reaching normal levels on Dex withdrawal, whereas in serum, it showed a significant decrease throughout the experimental period. Mean arterial pressure (MAP) and heart rate increased significantly, while a significant elevation in the ST segment was noticed during administration as well as after withdrawal of dex. The TBA-reactants levels were found to increase in heart and kidney during days 12 and 16 of administration with Dex and even after withdrawal of Dex, the levels were insignificantly elevated. The level of glutathione in heart and kidney increased from day 4 onwards and reached normalcy during the later stages of treatment and after withdrawal of Dex. The total sulfhydryl groups exhibited a significant increase in both heart and kidney throughout the experiment. The antioxidant enzymes such as catalase, superoxide dismutase, glutathione peroxidase and glutathione S-transferase exhibited a significant decrease in heart during Dex administration whereas, in kidney, they exhibited a significant increase during treatment and after withdrawal of Dex. Thus, Dex induced rise in mean arterial pressure, significant alterations in electrocardiographic parameters and also marked alterations in enzymatic and nonenzymatic antioxidant levels and in the TBA-reactants level in heart and kidney.  相似文献   
34.
目的:探讨常规心电图(ECG)与冠脉造影术(CAG)在冠心病诊断中的效果。方法:选取100例冠心病患者,入院后先行CAG,后经ECG检查,通过CAG检查的冠脉狭窄程度、冠脉病变支数与ECG检查结果的对比两种检查方法对冠心病诊断结果,评价ECG与CAG在冠心病诊断中的临床价值。结果:CAG诊断冠心病的阳性诊断率82.0%,ECG诊断冠心病阳性诊断率为79.0%,两组阳性诊断率相比,无统计学差异(P0.05)。ECG对三组冠心病患者的灵敏度分别为65.0%,92.6%,96.9%,冠脉狭窄程度50%-70%时,灵敏度低于其他两组(P0.05)。经CAG诊断为冠脉单支病变、双支病变、三支病变患者,采用ECG诊断时,组间灵敏度相比,差异有统计学意义(P0.05)。结论:ECG多支病变冠心病患者容易出现漏诊、误诊情况,CAG与ECG诊断灵敏度相当,可直观反映冠脉病变情况。  相似文献   
35.
基于替代数据(Surrogate)思想的复杂度归一化方法,克服了一般复杂度对信号采样长度与采样频率的敏感性。文章对在生物医学信号复杂度分析中最有潜在应用价值的近似熵和C0复杂度进行了归一化。应用该方法可以有效地反映人体心脏某些病理状态之间的差别。同时,通过比较各种复杂度指标发现,C0复杂度和近似熵对采样长度的敏感性最弱,适用于短数据量的信号分析。  相似文献   
36.
B-type natriuretic peptide (BNP) is a diagnostic and prognostic tool in heart failure and also in Chagas disease, which is caused by the protozoan Trypanosoma cruzi and has cardiomyopathy as a main feature. BNP lipolytic actions and T. cruzi infection in the adipose tissue have been recently described. We aim to investigate the relationship between BNP and anthropometric measures and whether it is influenced by T. cruzi infection. We measured BNP, body mass index (BMI), waist circumference (WC), triceps skin-fold thickness (TSF) and performed serological, biochemical and electrocardiographic exams in 1398 subjects (37.5% infected with T. cruzi) in a community-dwelling elderly population in Bambui city, Brazil. Linear multivariate regression analysis was performed to investigate determinants of BNP levels. BNP levels were significantly (p < 0.05) higher in T. cruzi-infected subjects than in the non-infected group (median = 121 and 64 pg/mL, respectively). BMI, WC and TSF in infected subjects were significantly lower than those in non-infected subjects (24.3 vs. 25.5 kg/m2; 89.2 vs. 92.4 cm; and 14.5 vs. 16.0 mm, respectively). There was an inverse relationship between BNP levels and BMI (b = −0.018), WC (b = −0.005) and TSF (b = −0.193) levels. Infected and non-infected groups showed similar inverse relationships between BNP and BMI (b = −0.021 and b = −0.015, respectively). In conclusion, there was an inverse relationship between BNP levels and the anthropometric measures. Despite the actions in the adipose tissue, T. cruzi infection did not modify the associations between BNP and BMI, suggesting that body mass does not modify the accuracy of BNP in Chagas disease.  相似文献   
37.

Background

Recent studies suggested that resting heart rate (RHR) might be an independent predictor of cardiovascular mortality and morbidity. Nonetheless, the interrelation between RHR and cardiovascular diseases is not clear. In order to resolve this puzzle, the importance of genetic determinants of RHR has been recently suggested, but it needs to be further investigated.

Objective

The aim of this study was to estimate the contribution of common genetic variations on RHR using Genome Wide Association Study.

Methods

We performed a Genome Wide Association Study in an isolated population cohort of 1737 individuals, the Italian Network on Genetic Isolates — Friuli Venezia Giulia (INGI-FVG). Moreover, a haplotype analysis was performed. A regression tree analysis was run to highlight the effect of each haplotype combination on the phenotype.

Results

A significant level of association (p < 5 × 10− 8) was detected for Single Nucleotide Polymorphisms (SNPs) in two genes expressed in the heart: MAML1 and CANX. Founding that the three different variants of the haplotype, which encompass both genes, yielded a phenotypic correlation. Indeed, a haplotype in homozygosity is significantly associated with the lower quartile of RHR (RHR ≤ 58 bpm). Moreover no significant association was found between cardiovascular risk factors and the different haplotype combinations.

Conclusion

Mastermind-like 1 and Calnexin were found to be associated with RHR. We demonstrated a relation between a haplotype and the lower quartile of RHR in our populations. Our findings highlight that genetic determinants of RHR may be implicated in determining cardiovascular diseases and could allow a better risk stratification.  相似文献   
38.
《Comptes rendus biologies》2014,337(11):609-624
The biological information coming from electrophysiologic sensors like ECG, pulse sensor or from molecular signal devices like NMR spectrometry has to be visualized and manipulated in a compressed way for an efficient medical use by clinicians, if stored in scientific data bases or in personalized patient records repositories. Here, we define a new transform called Dynalet based on Liénard ordinary differential equations susceptible to model the mechanism at the source of the studied signal, and we propose to apply this new technique first to the modelling and compression of real biological periodic signals like ECG and pulse rhythm. We consider that the cardiovascular activity results from the summation of cellular oscillators located in the cardiac sinus node and we show that, as a result, the van der Pol oscillator (a particular Liénard system) fits well the ECG signal and the pulse signal. The reconstruction of the original signal (pulse or ECG) using Dynalet transform is then compared with that of Fourier, counting the number of parameters to be set for obtaining an expected signal-to-noise ratio. Then, we apply the Dynalet transform to the modelling and compression of molecular spectra obtained by protein NMR spectroscopy. The reconstruction of the original signal (peak) using Dynalet transform is again compared with that of Fourier. After reconstructing visually the peak, we propose to periodize the signal and give it to hear, the whole process being called the protein “stethoscope”.  相似文献   
39.
We have identified a hitherto genetic polymorphism of apolipoprotein A-IV (apo-IV). The molecular basis for this polymorphism is an A to G substitution at nucleotide 1687 resulting in an Asn to Ser change of amino acid 127. The frequencies of the two apoA-IV alleles (designated apoA-IV127Asn and apoA-IV127Ser), determined by Hinc II restriction analysis of PCR amplified exon three of the apoA-IV gene, were 0.788 and 0.212, respectively, in a Finnish population sample. Allele frequencies of another polymorphism due to a Thr to Ser substitution at amino acid 347 were determined using Hinf I restriction analysis. The allele frequencies were 0.823 for apoA-IV347Thr and 0.177 for apoA-IV247Ser. None of the apoA-IV polymorphisms (apoA-IV127:Asn→Ser, apoA-IV347:Thr→Ser and apoA-IV360:Gln→His) had any effect of plasma lipid and lipoprotein concentrations in cohorts of dyslipidemic men and in a population sample of normolipidemic controls. There was also no association between the history of previous myocardial infarction and any of the apoA-IV alleles.  相似文献   
40.
Recent studies have suggested that certain (?)-epicatechin-containing foods have a blood pressure-lowering capacity. The mechanisms underlying (?)-epicatechin action may help prevent oxidative damage and endothelial dysfunction, which have both been associated with hypertension and certain brain disorders. Moreover, (?)-epicatechin has been shown to modify metabolic profile, blood's rheological properties, and to cross the blood-brain barrier. Thus, (?)-epicatechin causes multiple actions that may provide unique synergy beneficial for cardiovascular and neuropsychological health. This review summarises the current knowledge on the biological actions of (?)-epicatechin, related to cardiovascular and brain functions, which may play a remarkable role in human health and longevity.  相似文献   
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