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991.
Lena Marinova Tatyana Hadjieva Emil Kanchev Svetla Vicheva 《Reports of Practical Oncology and Radiotherapy》2015,20(1):72-76
Primary osteogenic sarcoma of the breast is a rare neoplasm, diagnosed mainly by pathohistological and immunohistochemical analysis.We hereby present a case of primary osteogenic sarcoma in the right breast of a 62-year-old woman with synchronous appearance of an invasive ductal carcinoma. Clinical findings are manifested with two separate painless formations 2.5 cm/2 cm and 1.5 cm/1 cm in size, located on the border of the upper and lower lateral quadrant of the right breast. No axillary lymphadenopathy was diagnosed. The pathohistological and immunohistochemistry findings of both tumors revealed a synchronous manifestation of two distinct neoplasms – epithelial and non-epithelial. Multimodality treatment consisted of Patey''s radical mastectomy; 3 cycles of adjuvant chemotherapy; postoperative 50 Gy radiotherapy to the chest wall followed by additional 3 cycles of chemotherapy and anti-estrogen hormonotherapy.Due to the rarity of osteogenic mammary sarcoma, even more so in a combination with epithelial breast tumors, its clinical features are unclear and optimal treatment remains controversial. Considering the poor prognosis of the combination of both malignomas, we discuss a number of diagnostic and therapeutic issues. 相似文献
992.
Trace analysis of N‐acetyl‐L‐cysteine using luminol–H2O2 chemiluminescence system catalyzed by silver nanoparticles 下载免费PDF全文
N‐Acetyl‐L‐cysteine (NAC) can inhibit the luminol–H2O2, reaction, which is catalyzed by silver nanoparticles. Based on this phenomenon a new method was developed for NAC determination. Under optimum conditions, a linear relationship between chemiluminescence intensity and NAC concentration was found in the range 0.034–0.98 µg/mL. The detection limit was 0.010 µg/mL (S/N =3), and the relative standard deviation (RSD) was <5% for 0.480 µg/mL NAC (n =5). This simple, sensitive and inexpensive method has been applied to measure the concentration of NAC in pharmaceutical tablets. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
993.
994.
Gianluigi Forloni Mauro Tettamanti Ugo Lucca Yasmin Albanese Elena Quaglio Roberto Chiesa Alessandra Erbetta Flavio Villani Veronica Redaelli Fabrizio Tagliavini Vladimiro Artuso Ignazio Roiter 《朊病毒》2015,9(2):75-79
The text describes a preventive clinical trial with drug treatment in a very rare neurodegenerative disease (Fatal familial Insomnia, FFI) designed with the help of individuals at genetic risk of developing the disease, asymptomatic carriers, who have agreed to be exposed over a 10-year period to doxycycline, an antibiotic with anti-prion activity. At least 10 carriers of the FFI mutation over 42 y old will be treated with doxycycline (100 mg/die) and the incidence of the disease will be compared to that of an historical dataset. For ethical reasons a randomized, double-blind, placebo-controlled trial was not feasible, however the study design and the statistical analysis ensure the scientific value of the results. This approach might represent an important breakthrough in terms of potential therapy and knowledge of rare diseases that could give some hopes to these neglected patients. 相似文献
995.
Effects of grass species and grass growth on atmospheric nitrogen deposition to a bog ecosystem surrounded by intensive agricultural land use 下载免费PDF全文
Miriam Hurkuck Christian Brümmer Karsten Mohr Oliver Spott Reinhard Well Heinz Flessa Werner L. Kutsch 《Ecology and evolution》2015,5(13):2556-2571
We applied a 15N dilution technique called “Integrated Total Nitrogen Input” (ITNI) to quantify annual atmospheric N input into a peatland surrounded by intensive agricultural practices over a 2-year period. Grass species and grass growth effects on atmospheric N deposition were investigated using Lolium multiflorum and Eriophorum vaginatum and different levels of added N resulting in increased biomass production. Plant biomass production was positively correlated with atmospheric N uptake (up to 102.7 mg N pot−1) when using Lolium multiflorum. In contrast, atmospheric N deposition to Eriophorum vaginatum did not show a clear dependency to produced biomass and ranged from 81.9 to 138.2 mg N pot−1. Both species revealed a relationship between atmospheric N input and total biomass N contents. Airborne N deposition varied from about 24 to 55 kg N ha−1 yr−1. Partitioning of airborne N within the monitor system differed such that most of the deposited N was found in roots of Eriophorum vaginatum while the highest share was allocated in aboveground biomass of Lolium multiflorum. Compared to other approaches determining atmospheric N deposition, ITNI showed highest airborne N input and an up to fivefold exceedance of the ecosystem-specific critical load of 5–10 kg N ha−1 yr−1. 相似文献
996.
A novel endo‐β‐N‐acetylglucosaminidase releases specific N‐glycans depending on different reaction conditions 下载免费PDF全文
Juliana Maria Leite Nobrega De Moura Bell Steven A. Frese Yan Liu David A. Mills David E. Block Daniela Barile 《Biotechnology progress》2015,31(5):1323-1330
Milk glycoproteins are involved in different functions and contribute to different cellular processes, including adhesion and signaling, and shape the development of the infant microbiome. Methods have been developed to study the complexities of milk protein glycosylation and understand the role of N‐glycans in protein functionality. Endo‐β‐N‐acetylglucosaminidase (EndoBI‐1) isolated from Bifidobacterium longum subsp. infantis ATCC 15697 is a recently isolated heat‐stable enzyme that cleaves the N‐N′‐diacetyl chitobiose moiety found in the N‐glycan core. The effects of different processing conditions (pH, temperature, reaction time, and enzyme/protein ratio) were evaluated for their ability to change EndoBI‐1 activity on bovine colostrum whey glycoproteins using advanced mass spectrometry. This study shows that EndoBI‐1 is able to cleave a high diversity of N‐glycan structures. Nano‐LC‐Chip–Q‐TOF MS data also revealed that different reaction conditions resulted in different N‐glycan compositions released, thus modifying the relative abundance of N‐glycan types. In general, more sialylated N‐glycans were released at lower temperatures and pH values. These results demonstrated that EndoBI‐1 is able to release a wide variety of N‐glycans, whose compositions can be selectively manipulated using different processing conditions. © 2015 American Institute of Chemical Engineers Biotechnol. Prog., 31:1323–1330, 2015 相似文献
997.
为了解氮肥和钙肥对烤烟(Nicotiana tabacum)生长的影响,对成熟期烤烟的根系形态、生理代谢指标和产量进行了研究。结果表明,与施0.12 g kg-1氮相比,施0.20 g kg-1氮的烤烟根系最长侧根长、根系体积、根干重、叶干重和可溶性蛋白质含量均极显著升高,MDA含量极显著下降,SOD活性显著下降,但对侧根数、CAT活性和O2·的影响均不显著。施钙0.40 g kg-1,根系体积、侧根数、CAT和SOD活性以及可溶性蛋白质含量均比对照提高,MDA含量和O2·则降低;施钙1.00 g kg-1,最长侧根长、根干重和叶干重均提高。氮×钙互作对烤烟的最长侧根长、根系体积、根干重、叶干重和生理代谢指标的影响均极显著,但对侧根数的影响不显著。因此,施0.20 g kg-1氮和0.40 g kg-1钙能最大限度地改善烤烟根系形态、生理状况及提高产量。 相似文献
998.
Erpeng Liu Lei Lv Yonghao Zhan Yuan Ma Jinjin Feng Yulin He Yibo Wen Yanping Zhang Qingsong Pu Fengping Ji Xinghuan Yang Jian Guo Wen 《Journal of cellular and molecular medicine》2021,25(16):7660
Renal fibrosis induced by urinary tract obstruction is a common clinical occurrence; however, effective treatment is lacking, and a deeper understanding of the mechanism of renal fibrosis is needed. Previous studies have revealed that miR‐21 impacts liver and lung fibrosis progression by activating the SPRY1/ERK/NF‐kB signalling pathway. However, whether miR‐21 mediates obstructive renal fibrosis through the same signalling pathway has not been determined. Additionally, studies have shown that N6‐methyladenosine (m6A) modification‐dependent primary microRNA (pri‐microRNA) processing is essential for maturation of microRNAs, but its role in the maturation of miR‐21 in obstructive renal fibrosis has not yet been investigated in detail. To address these issues, we employed a mouse model of unilateral ureteral obstruction (UUO) in which the left ureters were ligated for 3, 7 and 14 days to simulate the fibrotic process. In vitro, human renal proximal tubular epithelial (HK‐2) cells were transfected with plasmids containing the corresponding sequence of METTL3, miR‐21‐5p mimic or miR‐21‐5p inhibitor. We found that the levels of miR‐21‐5p and m6A modification in the UUO model groups increased significantly, and as predicted, the SPRY1/ERK/NF‐kB pathway was activated by miR‐21‐5p, confirming that miR‐21‐5p plays an important role in obstructive renal fibrosis by enhancing inflammation. METTL3 was found to play a major catalytic role in m6A modification in UUO mice and drove obstructive renal fibrosis development by promoting miR‐21‐5p maturation. Our research is the first to demonstrate the role of the METTL3‐m6A‐miR‐21‐5p‐SPRY1/ERK/NF‐kB axis in obstructive renal fibrosis and provides a deeper understanding of renal fibrosis. 相似文献
999.
Ryan D. Briscoe Runquist Eric Chu Justin L. Iverson Jason C. Kopp David A. Moeller 《Evolution; international journal of organic evolution》2014,68(10):2885-2900
A major goal of speciation research is to understand the processes involved in the earliest stages of the evolution of reproductive isolation (RI). One important challenge has been to identify systems where lineages have very recently diverged and opportunities for hybridization are present. We conducted a comprehensive examination of the components of RI across the life cycle of two subspecies of Clarkia xantiana, which diverged recently (ca. 65,000 bp). One subspecies is primarily outcrossing, but self‐compatible, whereas the other is primarily selfing. The subspecies co‐occur in a zone of sympatry but hybrids are rarely observed. Premating barriers resulted in nearly complete isolation in both subspecies with flowering time and pollinator preference (for the outcrosser over the selfer) as the strongest barriers. We found that the outcrosser had consistently more competitive pollen, facilitating hybridization in one direction, but no evidence for pollen–pistil interactions as an isolating barrier. Surprisingly, postzygotic isolation was detected at the stage of hybrid seed development, but in no subsequent life stages. This crossing barrier was asymmetric with crosses from the selfer to outcrosser most frequently failing. Collectively, the results provide evidence for rapid evolution of multiple premating and postzygotic barriers despite a very recent divergence time. 相似文献
1000.
Jane M. Reid Peter Arcese Lukas F. Keller Sylvain Losdat 《Evolution; international journal of organic evolution》2014,68(8):2357-2370
Ongoing evolution of polyandry, and consequent extra‐pair reproduction in socially monogamous systems, is hypothesized to be facilitated by indirect selection stemming from cross‐sex genetic covariances with components of male fitness. Specifically, polyandry is hypothesized to create positive genetic covariance with male paternity success due to inevitable assortative reproduction, driving ongoing coevolution. However, it remains unclear whether such covariances could or do emerge within complex polyandrous systems. First, we illustrate that genetic covariances between female extra‐pair reproduction and male within‐pair paternity success might be constrained in socially monogamous systems where female and male additive genetic effects can have opposing impacts on the paternity of jointly reared offspring. Second, we demonstrate nonzero additive genetic variance in female liability for extra‐pair reproduction and male liability for within‐pair paternity success, modeled as direct and associative genetic effects on offspring paternity, respectively, in free‐living song sparrows (Melospiza melodia). The posterior mean additive genetic covariance between these liabilities was slightly positive, but the credible interval was wide and overlapped zero. Therefore, although substantial total additive genetic variance exists, the hypothesis that ongoing evolution of female extra‐pair reproduction is facilitated by genetic covariance with male within‐pair paternity success cannot yet be definitively supported or rejected either conceptually or empirically. 相似文献