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81.
Lichen planus (LP) is a common mucocutaneous disease of unknown aetiology with various geographical prevalence, may be related to some serious disorders such as squamous cell carcinoma and often remains underdiagnosed. The aim of this retrospective study was to thoroughly determine localization and clinical characteristics of LP lesions in a cohort of 173 Slovenian patients in association to the presence of accompanying symptoms and history of potential stressful events. Isolated cutaneous lesions of LP were found in 56.6% and isolated oral LP in 3.5% of patients. Thirty-four percent presented orocutaneous LP, whereas genitocutaneous LP was noted in 1.2%, orogenito-cutaneous LP in 4% and orogenital LP in 0.5% of patients. Underlying stressful events were noted in 36 out of 137 (26.3%) patients. Despite obviously visible localization of the lesions various medical specialists should be familiar with LP and thoroughly examine the complete skin, as well as oral, genital and anal mucosa in each LP patient to avoid a delay in diagnosing this disease and possibly disclose a much serious underlying condition. Psychological support should be offered, if needed.  相似文献   
82.
Beta cell apoptosis is a hallmark of diabetes. Since we have previously shown that galectin‐3 deficient (LGALS3?/?) mice are relatively resistant to diabetes induction, the aim of this study was to examine whether beta cell apoptosis depends on the presence of galectin‐3 and to delineate the underlying mechanism. Deficiency of galectin‐3, either hereditary or induced through application of chemical inhibitors, β‐lactose or TD139, supported survival and function of islet beta cells compromised by TNF‐α + IFN‐γ + IL‐1β stimulus. Similarly, inhibition of galectin‐3 by β‐lactose or TD139 reduced cytokine‐triggered apoptosis of beta cells, leading to conclusion that endogenous galectin‐3 propagates beta apoptosis in the presence of an inflammatory milieu. Exploring apoptosis‐related molecules expression in primary islet cells before and after treatment with cytokines we found that galectin‐3 ablation affected the expression of major components of mitochondrial apoptotic pathway, such as BAX, caspase‐9, Apaf, SMAC, caspase‐3, and AIF. In contrast, anti‐apoptotic molecules Bcl‐2 and Bcl‐XL were up‐regulated in LGALS3?/? islet cells when compared to wild‐type (WT) counterparts (C57BL/6), resulting in increased ratio of anti‐apoptotic versus pro‐apoptotic molecules. However, Fas‐triggered apoptotic pathway as well as extracellular signal‐regulated kinase 1/2 (ERK1/2) was not influenced by LGALS‐3 deletion. All together, these results point to an important role of endogenous galectin‐3 in beta cell apoptosis in the inflammatory milieu that occurs during diabetes pathogenesis and implicates impairment of mitochondrial apoptotic pathway as a key event in protection from beta cell apoptosis in the absence of galectin‐3. J. Cell. Physiol. 228: 1568–1576, 2013. © 2012 Wiley Periodicals, Inc.  相似文献   
83.

Purpose

To evaluate one-step topography-guided transepithelial ablation in the treatment of low to moderate myopic astigmatism using a 1KHz excimer laser.

Methods

Retrospective study of 117 consecutive eyes available for evaluation 12 months after surgery. Pre- and post-operative visual and refractive data as well as post-operative pain and haze were analyzed. A novel technique integrating custom refractive- and epithelial- ablation in a single uninterrupted procedure was used.

Results

The mean pre-operative spherical equivalent (SE) and the mean cylinder were: –3.22 diopters (D) ±1.54 (SD) (range –0.63 to –7.25 D) and –0.77 D ±0.65 (range 0 to –4.50 D), respectively. At 12 months after surgery: no eyes lost ≥2 lines of corrected distant visual acuity (CDVA). Safety and efficacy indexes were 1.27 and 1.09, respectively. Uncorrected distant visual acuity (UDVA) was ≥20/20 in 96.6% of the eyes. Manifest refraction spherical equivalent was within ±0.5 D of the desired refraction in 93.2% of the eyes. Average root mean square (RMS) wavefront error measured at central 6 mm, increased from 0.38 pre-operatively to 0.47 µm post-operatively. Refractive stability was achieved and sustained 1 month after surgery. No visually significant haze was registered during the observation period. Post-operative pain was reported in 4.5% of patients.

Conclusions

One-step transepithelial topography-guided treatment for low to moderate myopia and astigmatism performed with a 1 KHz laser, provided safe, effective, predictable and stable results with low pain and no visually significant haze.  相似文献   
84.
We have developed an array of seven deoxyribozyme-based molecular logic gates that behaves as a full adder in a single solution, with three oligonucleotides as inputs and two independent fluorogenic cleavage reactions as carry and sum outputs. The sum output consisted of four new deoxyribozyme-based logic gates: an ANDAND gate and three ANDNOTANDNOT gates. These gates required the design of a generic three-input deoxyribozyme-based logic gate that can use any three-way combination of activating or inactivating inputs. This generic gate design utilizes an additional inverting element that hybridizes to convert YES logic into NOT logic and vice versa. The system represents the first solution-phase, single test tube, enzymatic full adder and shows the complexity of control over molecular scale events that can be achieved with deoxyribozyme-based logic gates. Similar systems could be applied to control autonomous therapeutic and diagnostic devices.  相似文献   
85.
Tree cavities provide important habitat for wildlife. Effective landscape‐scale management of cavity‐dependent wildlife requires an understanding of where cavities occur, but tree cavities can be cryptic and difficult to survey. We assessed whether a landscape‐scale map of mature forest habitat availability, derived from aerial photographs, reflected the relative availability of mature trees and tree cavities. We assessed cavities for their suitability for use by wildlife, and whether the map reflected the availability of such cavities. There were significant differences between map categories in several characteristics of mature trees that can be used to predict cavity abundance (i.e. tree form and diameter at breast height). There were significant differences between map categories in the number of potential cavity bearing trees and potential cavities per tree. However, the index of cavity abundance based on observations made from the ground provided an overestimate of true cavity availability. By climbing a sample of mature trees we showed that only 5.1% of potential tree cavities detected from the ground were suitable for wildlife, and these were found in only 12.5% of the trees sampled. We conclude that management tools developed from remotely sensed data can be useful to guide decision‐making in the conservation management of tree cavities but stress that the errors inherent in these data limit the scale at which such tools can be applied. The rarity of tree cavities suitable for wildlife in our study highlights the need to conserve the tree cavity resource across the landscape, but also the importance of increasing the accuracy of management tools for decision‐making at different scales. Mapping mature forest habitat availability at the landscape scale is a useful first step in managing habitat for cavity‐dependent wildlife, but the potential for overestimating actual cavity abundance in a particular area highlights the need for complementary on‐ground surveys.  相似文献   
86.
Information on gene expression and regulation is expanding rapidly, and the complexity of the experimental design and data makes unique demands on databases to store the results. We describe a prototype database containing experimental results on the expression of mammalian β-like globin genes, along with several query methods for accessing the information. The database has tables for DNA transfer experiments, protein–DNA binding results, and positions of DNase hypersensitive sites, which make extensive use of nested data structures. Comparison of data from various mammals is accomplished by providing a common coordinate system via a simultaneous alignment of matching DNA sequences. Interactive access to the database is available at a site called theGlobin Gene Serveron the World Wide Web (http://globin.cse. psu.edu). This software should be useful for any genetic system in which DNA sequence data are available.  相似文献   
87.
The binding between marcrophage-like cells J774G8 and Leishmania braziliensis (NR) promastigotes was studied in vitro by a radioisotopic assay under various conditions in the absence of serum. Different sugars, N-acetyl-D-glucosamine, D-glucose, D-mannose, D-galactose, and chitin, diminished the binding of the parasite, whereas other sugars, D-arabinose, D-fucose and D-xylose, did not affect the binding. The presence of a lectin-like ligand specific for N-acetyl-D-glucosamine has been detected on the cell surface of the Leishmania braziliensis (NR) by fluorescence microscopy.These data suggest that the binding of the parasite to the host's cell is a ligand-receptor interaction which involves the participation of a lectin-like component on the parasite cell surface.  相似文献   
88.
There are many opened questions about the precocious role of oxidative stress in the physiopathology of the early stage of transitory ischemic attack (TIA) and defined focal brain ischemia, as well as about its correlation with clinical severity, short-lasting and clinical outcome prediction in these conditions. The study evaluates the values of glutathione (GSH), glutathione peroxidase, and superoxide dismutase (SOD) in hemolysates and total thiol content (–SH), advanced oxidation protein products (AOPP), SOD, and malondialdehyde (MDA) in plasma, in TIA and stroke patients in the early stage of their neurological onset. The results are interpreted in view of the potential relationship between tested parameters and clinical severity and clinical outcome prediction. Better hemolysates’ and total antioxidant profile with higher values of AOPP were observed in TIA compared to stroke patients (p < 0.05). The stroke patients with initially better clinical presentation showed better antioxidant profile with lower values of AOPP (p < 0.05). In TIA patients, this was observed for GSH, –SH content, and AOPP (p < 0.05), which correlated with a short risk for stroke occurrence in this group (p < 0.01). Beyond MDA values, all tested parameters showed correlation with clinical outcome in stroke patients (p < 0.05). The measurement of oxidative stress in TIA and stroke patients would be important for identifying patients’ subgroups which might receive supporting therapy providing better neurological recovery and clinical outcome. That approach might give us an additional view of a short-lasting risk of stroke occurrence after TIA, and its clinical outcome and prognosis.  相似文献   
89.
90.
Identifying factors influencing the demographics of threatened species is essential for conservation, but a lack of comprehensive demographic data often impedes the effective conservation of rare and mobile species. We monitored breeding of critically endangered and semi‐nomadic Regent Honeyeaters Anthochaera phrygia (global population c. 100 pairs) over 3 years throughout their range. Overall nest success probability (0.317) was highly spatially variable and considerably lower than previous estimates for this (and many other honeyeater) species, as was productivity of successful nests (mean 1.58 juveniles fledged). Nest surveillance revealed high predation rates by a range of birds and arboreal mammals as the primary cause of nest failure. An estimated 12% of pairs either failed to establish a territory or their nests did not reach the egg stage. We also found a male bias to the adult sex ratio, with an estimated 1.18 males per female. Juvenile survival for the first 2 weeks after fledging was high (86%). Management interventions that aim to increase nest success in areas of low nest survival must be investigated to address an apparent decline in reproductive output and avoid extinction of the Regent Honeyeater. We show that temporal and spatial variation in the breeding success of rare and highly mobile species can be quantified with robust population monitoring using sampling regimens that account for their life histories. Understanding the causes of spatio‐temporal variation in breeding success can enhance conservation outcomes for such species through spatially and temporally targeted recovery actions.  相似文献   
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