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81.
Iga Pachta Marcin Kleibert Anna M. Czarnecka Mateusz Spaek Anna Szumera-Ciekiewicz Piotr Rutkowski 《International journal of molecular sciences》2021,22(10)
Adnexal tumors of the skin are a rare group of benign and malignant neoplasms that exhibit morphological differentiation toward one or more of the adnexal epithelium types present in normal skin. Tumors deriving from apocrine or eccrine glands are highly heterogeneous and represent various histological entities. Macroscopic and dermatoscopic features of these tumors are unspecific; therefore, a specialized pathological examination is required to correctly diagnose patients. Limited treatment guidelines of adnexal tumor cases are available; thus, therapy is still challenging. Patients should be referred to high-volume skin cancer centers to receive an appropriate multidisciplinary treatment, affecting their outcome. The purpose of this review is to summarize currently available data on pathogenesis, diagnosis, and treatment approach for apocrine and eccrine tumors. 相似文献
82.
Sinkhole ponds originated as a result of human activity leading to ground subsidence and create important habitats for the diversity of benthos fauna in urban areas. The objectives of this study were to determine whether the context (roadside/forest) is important in relation to the composition and diversity of macroinvertebrates, and to evaluate the influence of environmental factors (e.g. water quality) on snail communities. The study showed that the context of ponds had an impact on the properties of the water. Ponds located along roads were characterised by higher conductivity and a higher concentration of calcium and phosphates. The fauna was composed of 47 taxa, including 26 taxa found in both pond contexts. The density of macroinvertebrates was higher in forest ponds. CCA analysis showed that conductivity and concentration of nitrates were most strongly associated with the distribution of gastropods. Alien snail species more often inhabited the roadside ponds. 相似文献
83.
The ray-tracing method is applied to design a wavelength multiplexer-demultiplexer by the use of planar microlenses as focusing and collimating elements. By simulating both uniform and Gaussian intensity distributions of the input sources, we find the position of the input-output components of the wavelength multiplexe-rdemultiplexer, which maximizes the coupling efficiency in each channel. Losses are also evaluated. 相似文献
84.
Yuji Yamaguchi Dong Han Ha Fumitoshi Iga Yoshikazu Nishihara 《Journal of Superconductivity》1994,7(2):291-293
The ac susceptibility under a biased dc field near the irreversibility field (H
irr) of a Bi2Sr2CaCu2O8 single crystal has been measured. The frequency dependence, the ac-power dependence, and the nearly lossless character of the vs.H
dc curve forHa-axis have been roughly explained from a reversible (elastic) fluxoid motion, while those forH c-axis have been explained from a thermally assisted flux-flow (TAFF) model. The obtained parameters are discussed in relation to anisotropic flux-pinning mechanisms in the layered structure of this compound. 相似文献
85.
Analysis of Molecular Species Profiles of Ceramide-1-phosphate and Sphingomyelin Using MALDI-TOF Mass Spectrometry 下载免费PDF全文
Ryouhei Yamashita Yumika Tabata Erina Iga Michiyasu Nakao Shigeki Sano Kentaro Kogure Akira Tokumura Tamotsu Tanaka 《Lipids》2016,51(2):263-270
Ceramide‐1‐phosphate (C1P) is a potential signaling molecule that modulates various cellular functions in animals. It has been known that C1P with different N‐acyl lengths induce biological responses differently. However, molecular species profiles of the C1P in animal tissues have not been extensively examined yet. Here, we developed a method for determination of the molecular species of a C1P using matrix‐assisted laser desorption/ionization time‐of‐flight mass spectrometry with Phos‐tag, a phosphate capture molecule. The amounts of total C1P in skin, brain, liver, kidney and small intestine of mice were determined to be 344, 151, 198, 96 and 90 pmol/g wet weight, respectively. We found a C1P species having an α‐hydroxypalmitoyl residue (h‐C1P, 44 pmol/g wet weight) in mouse skin. The h‐C1P was detected only in the skin, and not other tissues of mice. The same analysis was applied to sphingomyelin after conversion of sphingomyelin to C1P by Streptomyces chromofuscus phospholipase D. We found that molecular species profiles of sphingomyelin in skin, kidney and small intestine of mice were similar to those of C1P in corresponding tissues. In contrast, molecular species profiles of sphingomyelin in liver and brain were quite different from those of C1P in these tissues, indicating selective synthesis or degradation of C1P in these tissues. The method described here will be useful for detection of changes in molecular species profiles of C1P and sphingomyelin. 相似文献
86.
Research activities on semiconductor lasers related to optical communications and information technologies are reviewed. 相似文献
87.
Abstract A straight mixing waveguide has been introduced into a mesh waveguide star coupler for the purpose of reducing its excess loss. A preferable structure for a 4 × 4 star coupler has been found by a ray-tracing method. Loss reduction by 3·5 dB compared with a previous structure is demonstrated in an ion-diffused waveguide. 相似文献
88.
Despite substantial progress of research efforts in the field of photovoltaic (PV) power generation, some serious problems remain to be solved, including a fairly low energy generated by PV systems in comparison to the expected output, and a broad spread of output values among individual PV systems. The expected level of generated energy is usually evaluated by means of such coefficients as “the performance ratio” which is obtained as the energy actually generated by a PV array over a period of 1 year divided by the calculated output over the same period. However, this method has some limitations, such as the necessity to continuously perform data measurements over a long time, difficulties in the examination of factors reducing the level of the generated energy or improving the system efficiency, and so on. In this study, the authors propose a new method of accurate evaluation of the generated energy. The authors also examined a method for classifying the losses caused by the rise of the PV cell temperature and presented a method of data measurements over a short time period. The proposed method can also be applied to the classification and analysis of losses occurring at the time of the MPPT operation of the system (Pmax operation). © 2006 Wiley Periodicals, Inc. Electr Eng Jpn, 154(4): 24–33, 2006; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.20222 相似文献
89.
Masahide Yamaguchi Atsushi Iga Kaoru Ishihara Daishiro Wada Kiyoaki Yoshii Osamu Sueda 《Electrical Engineering in Japan》2004,147(4):20-31
In this paper we examine the merits that a practical photovoltaic system combining photovoltaic generation with storage batteries would provide if used in ordinary residences. Various configurations and operation methods could be envisaged for such a system. In this research we examined the optimal battery capacity, operation methods, and economic effects for a system emphasizing an economical merit for the user. We first calculated the hourly amount of photovoltaic generated electricity each month, and used data on average load patterns from actual measurements to calculate battery capacity. Next, taking battery capacity and photovoltaic module capacity/price as parameters, we calculated and evaluated the economic merit for ordinary residences. The result showed that the optimal battery capacity for combination with 3‐ or 5‐kW photovoltaic generation is around 10 kWh, and that a combined system provides a merit even though it entails higher photovoltaic module costs than the use of photovoltaic generation alone. © 2004 Wiley Periodicals, Inc. Electr Eng Jpn, 147(4): 20–31, 2004; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.10302 相似文献
90.
Takeshita T. Yamamoto M. Iga R. Sugo M. Kondo Y. Kato K. 《Electron Devices, IEEE Transactions on》2007,54(8):1852-1859
We investigated the degradation behavior of distributed feedback lasers by employing the optical-beam-induced current measurement technique. We showed that the degradation mechanism is governed by diffused defects at the waveguide other than those in the vicinity of the antireflection facet. In addition, we found that a diffused source is probably generated in the upper InP cladding layer above the grating during the growth of the upper InP cladding layer. 相似文献