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We conducted a review of the literature regarding epidemiology, clinical, electrocardiographic and vectorcardiographic aspects, classification, and differential diagnosis of left posterior fascicular block.Isolated left posterior fascicular block (LPFB) is an extremely rare finding both in the general population and in specific patient groups. In isolated LPFB 20% of the vectorcardiographic (VCG) QRS loop is located in the right inferior quadrant and when associated with right bundle branch block (RBBB) ≥40%.The diagnosis of LPFB should always consider the clinical aspects, because a definite diagnosis cannot be made in the presence of right ventricular hypertrophy (RVH) (chronic obstructive pulmonary disease (COPD)/emphysema), extensive lateral myocardial infarction (MI) or extremely vertical heart.Intermittent LPFBs are never complete blocks (transient or second degree LPFB) and even in the permanent ones, one cannot be sure that they are complete. When LPFB is associated with RBBB and acute inferior MI, PR interval prolongation is very frequent.  相似文献   
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The cDNA for a β-glucosidase (EC3.2.1.21) was isolated from rye ( Secale cereale , cv Motto) and the sequence corresponding to the mature protein cloned into pET21a expression vector and used for transformation of Escherichia coli. The recombinant β-glucosidase expressed in E. coli was recognized by antibodies to maize β-glucosidase and exhibited the same kinetic properties on the endogenous substrates hydroxamic acid glucosides and artificial substrates as the native enzyme purified from rye. The enzyme monomer had an apparent molecular weight of about 67 kDa. The isolated cDNA was analysed with web-based chloroplast targeting prediction programs. The programs predicted a chloroplast targeting peptide with a cleavage site between amino acid 49 and 50. Sequence alignment of the plastidic rye β-glucosidase showed that the putative sites for substrate specificity of maize Glu1, W378 and F198 (F197) are conserved in the rye enzyme, whereas F205, F466 and A467 of maize Glu1 are exchanged for histidine, glycine and serine, respectively, in rye. The plastidic β-glucosidase is expressed in all plant parts and the highest levels were found in the coleoptile and mesocotyl.  相似文献   
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In vegetable production, N balance surpluses are especially high which increases the risk of environmental pollution. The cultivation of N-efficient cultivars may contribute to alleviate the problem. A 2-year field experiment was conducted with eight white cabbage cultivars of three different maturity groups at two N fertilization levels. Genotypes differed both in N efficiency (head fresh weight at low N supply) and in yield at high N supply. These differences were not related to N uptake but to N utilization efficiency. At low N supply, harvest index was the main determining factor for genotypic yield differences. For earlier maturing cultivars a slower leaf emergence was responsible for the low harvest index. The response of the cultivars to low N supply was dependent on the weather conditions, particularly temperature, (highly significant year × cultivar × N supply interaction) at early growing stages. This suggests that breeding of cultivars with generally low-temperature tolerance could contribute to enhancing N utilization. Especially at high N supply, a high N harvest index was important for yield formation due to its effect on head water accumulation. For late cultivars, a high N retranslocation from leaves to the heads was related to yield both at low and high N supply. The study suggests that breeding of N-efficient cultivars may reduce N release to the environment by reducing the necessary N input and reducing the N content remaining in the crop residues.  相似文献   
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The epsilon wave of the electrocardiogram (ECG) together with fragmented QRS (fQRS), the terminal conduction delay, incomplete right bundle branch block (IRBBB) and complete/advanced RBBB (CRBBB) of peripheral origin are part of a spectrum of ventricular depolarization abnormalities of arrhythmogenic cardiomyopathy (AC). Although the epsilon wave is considered a major diagnostic criterion for AC since 2010 (AC Task Force Criteria), its diagnostic value is limited because it is a sign of the later stage of the disease. It would be more appropriate to say that the epsilon wave is a “hallmark” of AC, but is of low diagnostic sensitivity. Although the epsilon wave has high specificity for AC, it can be present in other pathological conditions. In this update we will cover the nomenclature, association with disease states and electrocardiographic aspects of the epsilon wave.  相似文献   
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The subcellular compartmentation of β -glucosidase was studied in rye, maize and wheat seedlings by immunocytochemical methods. For detection, we used a 10 nm gold-labeled secondary antibody, and results were observed using transmission electron microscopy. In all three species, β -glucosidase was found in plastids, cytoplasm and cell walls. In rye, gold particles were seen on cell walls and cytoplasm in epidermal cells of the root tip and shoot, in bundle sheath cells of the shoot and in all cells, except the vascular bundle cells of the coleoptile. Gold labeling was also observed in plastids of the bundle sheath cells of rye shoot tips and in cortical cells of root tips. In wheat, gold labeling was observed on cell walls and cytoplasm of epidermal cells in the shoot base and coleoptile, and on cell walls and plastids in epidermal cells of the root tip. In maize, gold labeling was mainly found in plastids or proplastids in vascular bundle cells and bundle sheath cells of the shoot, in bundle sheath cells of the coleoptile and in epidermal cells of the root. Some gold particles were also found in cell walls and cytoplasm of stomatal guard cells of the shoot base and vascular bundle cells of the shoot tip and in the cell walls of bundle sheath cells of the shoot tip and root tip epidermal cells. Results are discussed in relation to the role of β -glucosidase in hydroxamic acid release and overall defense mechanism of monocotyledons.  相似文献   
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The localization of β -glucosidase was determined at the tissue level in roots and shoots of rye, wheat and maize seedlings, using an immunohistochemical approach with antibodies directed against purified maize β -glucosidase as the primary antibody. In the roots, the β -glucosidase was found in the epidermis and the underlying cell layer. In the leaves, staining was seen in the epidermis (rye and wheat) and nearby vascular tissue (rye, wheat and maize). In all 3 species, β -glucosidase activity was highest in the coleoptile. Here the enzyme was restricted to the epidermis in wheat and to cells near the vascular tissue in maize, but was found in the whole tissue, except the vascular tissue, in rye. Maize, wheat and rye all contain hydroxamic acid glucosides and results are discussed in relation to a proposed role of β -glucosidase as part of a defense system releasing hydroxamic acid aglucone upon herbivore attack, pathogen penetration or aphid infestation.  相似文献   
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Myocardial infarction (MI) is divided into either ST elevation MI (STEMI) or non-ST elevation MI (NSTEMI), differing in a number of clinical characteristics. We sought to identify genetic variants conferring risk to NSTEMI or STEMI by conducting a genome-wide association study (GWAS) of MI stratified into NSTEMI and STEMI in a consecutive sample of 1,579 acute MI cases with 1,576 controls. Subsequently, we followed the results in an independent population-based sample of 562 cases and 566 controls, a partially independent prospective cohort (N = 16,627 with 163 incident NSTEMI cases), and examined the effect of disease-associated variants on gene expression in 513 healthy participants. Genetic variants on chromosome 1p13.3 near the damage-regulated autophagy modulator 2 gene DRAM2 associated with NSTEMI (rs656843; odds ratio 1.57, P = 3.11 × 10−10) in the case-control analysis with a consistent but not statistically significant effect in the prospective cohort (rs656843; hazard ratio 1.13, P = 0.43). These variants were not associated with STEMI (rs656843; odds ratio, 1.11, P = 0.20; hazard ratio 0.97, P = 0.87), appearing to have a pronounced effect on NSTEMI risk. A majority of the variants at 1p13.3 associated with NSTEMI were also associated with the expression level of DRAM2 in blood leukocytes of healthy controls (top-ranked variant rs325927, P = 1.50 × 10−12). The results suggest that genetic factors may in part influence whether coronary artery disease results in NSTEMI rather than STEMI.  相似文献   
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Background

The occurrence of variations in the spectrum of cardiovascular disease between different regions of the world and ethnic groups have been the subject of great interest. This study report the 24-h variation of myocardial infarction (MI) occurrence in patients recruited from CCU located in Argentina and Uruguay.

Methods

A cohort of 1063 patients admitted to the CCU within 24 h of the onset of symptoms of an acute MI was examined. MI incidence along the day was computed in 1 h-intervals.

Results

A minimal MI incidence between 03:00 and 07:00 h and the occurrence of a first maximum between 08:00 and 12:00 h and a second maximum between 15:00 and 22:00 h were verified. The best fit curve was a 24 h cosinor (acrophase ~ 19:00 h, accounting for 63 % of variance) together with a symmetrical gaussian bell (maximum at ~ 10:00 h, accounting for 37 % of variance). A similar picture was observed for MI frequencies among different excluding subgroups (older or younger than 70 years; with or without previous symptoms; diabetics or non diabetics; Q wave- or non-Q wave-type MI; anterior or inferior MI location). Proportion between cosinor and gaussian probabilities was maintained among most subgroups except for older patients who had more MI at the afternoon and patients with previous symptoms who were equally distributed among the morning and afternoon maxima.

Conclusion

The results support the existence of two maxima (at morning and afternoon hours) in MI incidence in the Argentine and Uruguayan population.  相似文献   
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