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191.
The J wave, also known as Osborn wave, is a deflection that can be observed on the surface ECG as a late delta wave, seen at the end of the QRS complex. In this case, a 75-year-old woman, after 1 day of continuous haemodialysis, showed a marked hypothermia (28.5°C) and severe hypokalaemia (1.7 mEq/l). Bradycardia was seen on the monitor and J waves were recognised on the ECG recording. After appropriate replacement of potassium and treatment of hypothermia, the J waves disappeared spontaneously. 相似文献
192.
In the Hruby Jeseník Mts of the Czech Republic, research was carried out from 2001–2005 aimed at completing an up-to-date
census of alpine juniper [Juniperus communis subsp. alpine (Smith) Čelakovsky] and an evaluation of the overall health status of the populations, and at investigating the impacts of
the main environmental factors on the viability of this species. 13 sites were identified with 283 individuals in total, but
the sites differed dramatically in the number of recorded individuals. Comparisons with historical literature sources show
that the species has been in decline. The main reasons for this decline include: a lack of suitable sites for colonization
connected with a lack of adequate disturbance factors, competition from shading trees, and the presumed high age of the juniper
populations combined with zero generative reproduction. More than two thirds of the individuals showed slight damage to their
assimilation system. A health status of bad or very bad was determined for 5 % of the alpine juniper individuals. These trees
in the Hruby Jeseník Mts are also exposed to pressure from some herbivore insects and mammals. The populations are not yet
in a literally critical state, but considering the range of impacts affecting them, it will be necessary to pay significant
attention to their conservation strategies. Some recommendations for future management are suggested. 相似文献
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Ali Solmaz Göksel Şener Şule Çetinel Meral Yüksel Cumhur Yeğen 《Free radical research》2013,47(6):594-603
Sprague Dawley rats of both sexes were injected with either saline or RVT (10 mg/kg) either before or after acetic acid ulcer induction and decapitated 3, 5 or 10 days after ulcer. In the saline-treated ulcer groups, macroscopically evident ulcers were observed, while RVT-pretreated or RVT-treated groups had lower macroscopic ulcer scores. Likewise, the microscopic damage scores were lower for the RVT-administered groups. Gastric myeloperoxidase activity, malondialdehyde, collagen and tumour necrosis factor-alpha levels, as well as luminol- and lucigenin-enhanced chemiluminescence levels that were elevated in the saline-administered ulcer groups, were depressed with both RVT-pretreatment and RVT-treatment. Moreover, depleted glutathione levels in the ulcer groups were increased back to control levels by both pre- and post-treatments of RVT. Results demonstrate that resveratrol has both protective and therapeutic effects on oxidative gastric damage by suppressing pro-inflammatory cascades, including the activation of pro-inflammatory cytokines, accumulation of neutrophils and release of oxygen-derived free radicals. 相似文献
196.
Actin protein has many other cellular functions such as movement, chemotaxis, secretion and cytodiaresis. Besides, it have structural function. Actin is a motor protein that it has an important role in the movement process of toxin in the cell. It is known that F-actin gives carriage support during the endosomal process. Actin is found in globular (G) and filamentous (F) structure in the cell. The helix of actin occurs as a result of polymerisation of monomeric G-actin molecules through sequential rowing, is called F-actin (FA). Actin interacts with a great number of cellular proteins along with cell skeleton and plasma membrane. It is also known that some bacterial toxins have ADP-ribosylation affect on actin. Diphteria toxin is the part which has the FA enzymatic activity corresponding the N-terminal section of the toxin, which inhibits the protein synthesis by ADP-ribosylating the elongation factor 2 in the presence of NAD. FA, taken into the cell by endocytosis inhibits protein synthesis by ADP-ribosyltransferase activity and breaks the cytoskeleton. In the studies both in vitro and in vivo, actin with interaction FA of diphteria toxin has been yet to be fully elucidated. The aim of this study was to determine the three dimensional structures of actin with interaction FA of diphteria toxin by the amprical methods and in paralel with the computing technology, theoretical methods have gained significant importance. In our study, actin with interaction FA of diphteria toxin has been determined as the most possible interaction area with the theoretical method; analogy modelling. This area has been closed in the presence of polypeptides and FA-actin interactions have been tested with the gel filtration chromatography techniques. As a result of the findings, we found that 15 amino acid artificial peptides (DAMYETMAQACAGNR) corresponding to 201–215 amino acid residues of FA interacts with G-actin and closes this area. Secondly, in the model formed with the analogy modelling, it appears that the most possible interaction area is between FA (tyr204) and G-actin (gly48). Results obtained from both theoretical and experimental data support the idea that the interaction occurs in this area. 相似文献
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Hamiyet Dönmez Nurcan Dursun Yusuf özkul Haulil DemirtaŞ 《Biological trace element research》1998,61(1):105-109
Sister chromatid exchange (SCE) in blood lymphocytes was determined in 32 male workers occupationally exposed to lead (Pb)
and zinc (Zn) and in 20 controls matched for age and smoking habits. Exposed workers have higher SCE mean values than control
workers (p < 0.01). In exposed persons, blood Pb concentrations were also significantly higher than controls (p < 0.0001), but the difference between Zn levels in the blood of these groups was not found to be significant (p > 0.05). Our results indicate that Pb may be genotoxic and harmful to human health. 相似文献
200.
Şerban Procheş John R. U. Wilson David M. Richardson Marcel Rejmánek 《Global Ecology and Biogeography》2012,21(5):513-523
Aim Pine trees (genus Pinus) represent an ancient lineage, naturally occurring almost exclusively in the Northern Hemisphere, but introduced and widely naturalized in both hemispheres. As large trees of interest to forestry, they attract much attention and their distribution is well documented in both indigenous and naturalized ranges. This creates an opportunity to analyse the relationship between indigenous and naturalized range sizes in the context of different levels of human usage, biological traits and the characteristics of the environments of origin. Location Global. Methods We combined and expanded pre‐existing data sets for pine species distributions and pine species traits, and used a variety of regression techniques (including generalized additive models and zero‐inflated Poisson models) to assess which variables explained naturalized and indigenous range sizes. Results Indigenous and naturalized range sizes are positively correlated but there are many notable exceptions. Some species have large indigenous ranges but small or no naturalized ranges, whereas others have small indigenous ranges, but have naturalized in many regions. Indigenous range is correlated to factors such as seed size (?), age at first reproduction (?), and latitude (+, supporting Rapoport's rule), but also to the extent of coverage of species in the forestry literature (+). Naturalized range size is strongly influenced by the extent of coverage of species in the forestry literature (+), a proxy for propagule pressure. Naturalization was also influenced by average elevation in the indigenous range (?) and age at first reproduction (?). Main conclusions The macroecological and evolutionary pressures facing plant groups are not directly transferable between indigenous and naturalized ranges. In particular, there are strong biases in species naturalization and expansion in invasive ranges that are unrelated to factors determining indigenous range size. At least for Pinus, a new set of macroecological patterns are emerging which are profoundly influenced by humans. 相似文献