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1.
The pathophysiology of Polycystic Ovary Syndrome (PCOS) is quite complex and different mechanisms could contribute to hyperandrogenism and anovulation, which are the main features of the syndrome. Obesity and insulin-resistance are claimed as the principal factors contributing to the clinical presentation; in normal weight PCOS either, increased visceral adipose tissue has been described. However, their role is still debated, as debated are the biochemical markers linked to obesity per se. Oxidative stress (OS) and low-grade inflammation (LGI) have recently been a matter of researcher attention; they can influence each other in a reciprocal vicious cycle. In this review, we summarize the main mechanism of radical generation and the link with LGI. Furthermore, we discuss papers in favor or against the role of obesity as the first pathogenetic factor, and show how OS itself, on the contrary, can induce obesity and insulin resistance; in particular, the role of GH-IGF-1 axis is highlighted. Finally, the possible consequences on vitamin D synthesis and activation on the immune system are briefly discussed. This review intends to underline the key role of oxidative stress and low-grade inflammation in the physiopathology of PCOS, they can cause or worsen obesity, insulin-resistance, vitamin D deficiency, and immune dyscrasia, suggesting an inverse interaction to what is usually considered.  相似文献   
2.
Drawn symbolic pictures are an extension of drawn pictures obtained by associating a symbol from an alphabet to each point of the picture. In the paper we will address some new interesting issues derived from the introduction of the symbols and we will identify the conditions, which ensure the preservation of properties holding for drawn pictures in the setting of the proposed extension.  相似文献   
3.
Interleukin (IL)-33 is a member of the interleukin (IL)-1 family of cytokines linked to the development of inflammatory conditions and cancer in the gastrointestinal tract. This study is designed to investigate whether IL-33 has a direct effect on human gastric epithelial cells (GES-1), the human gastric adenocarcinoma cell line (AGS), and the gastric carcinoma cell line (NCI-N87) by assessing its role in the regulation of cell proliferation, migration, cell cycle, and apoptosis. Cell cycle regulation was also determined in ex vivo gastric cancer samples obtained during endoscopy and surgical procedures. Cell lines and tissue samples underwent stimulation with rhIL-33. Proliferation was assessed by XTT and CFSE assays, migration by wound healing assay, and apoptosis by caspase 3/7 activity assay and annexin V assay. Cell cycle was analyzed by means of propidium iodine assay, and gene expression regulation was assessed by RT-PCR profiling. We found that IL-33 has an antiproliferative and proapoptotic effect on cancer cell lines, and it can stimulate proliferation and reduce apoptosis in normal epithelial cell lines. These effects were also confirmed by the analysis of cell cycle gene expression, which showed a reduced expression of pro-proliferative genes in cancer cells, particularly in genes involved in G0/G1 and G2/M checkpoints. These results were confirmed by gene expression analysis on bioptic and surgical specimens. The aforementioned results indicate that IL-33 may be involved in cell proliferation in an environment- and cell-type-dependent manner.  相似文献   
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Recently, a powerful two-phase method for restoring images corrupted with high level impulse noise has been developed. The main drawback of the method is the computational efficiency of the second phase which requires the minimization of a non-smooth objective functional. However, it was pointed out in (Chan et al. in Proc. ICIP 2005, pp. 125–128) that the non-smooth data-fitting term in the functional can be deleted since the restoration in the second phase is applied to noisy pixels only. In this paper, we study the analytic properties of the resulting new functional ℱ. We show that ℱ, which is defined in terms of edge-preserving potential functions φ α , inherits many nice properties from φ α , including the first and second order Lipschitz continuity, strong convexity, and positive definiteness of its Hessian. Moreover, we use these results to establish the convergence of optimization methods applied to ℱ. In particular, we prove the global convergence of some conjugate gradient-type methods and of a recently proposed low complexity quasi-Newton algorithm. Numerical experiments are given to illustrate the convergence and efficiency of the two methods.
Carmine Di FioreEmail:
  相似文献   
6.
In an investigation of the possible coexistence of superconductivity and magnetism, we have measured the Mössbauer effect of151Eu and119Sn in Eu z Sn 1–z Mo6S y (0z1,y7) between 0.05 and 4.2 K. The Eu spectra show a magnetic hyperfine splitting with a field of 27.3 T below 0.1 K; no fields in excess of 0.1 T have been observed at the Sn nuclei. For 0.1<T<0.5 K, the Eu Mössbauer spectra consist of a superposition of the static hyperfine spectrum observed forT0.1 K and a spectrum produced by electronic relaxation. In this intermediate temperature range the spectra can be understood as arising from ordered clusters in a paramagnetic surrounding, features we consider to be characteristic of a spin glass. The interaction between the Eu ions, and that between Eu ions and the superconducting Mod electrons, seem to be very weak.  相似文献   
7.
Multirotors, among all aerial vehicles, are fundamental instruments in many situations, i.e. video recording of sport events, leisure, environmental monitoring before or after a disaster. In particular, in the context of environmental monitoring, the possibility of following a predetermined path while avoiding obstacles is extremely relevant. In this work, we propose a novel method for path definition in presence of obstacles, which describes a curve as the intersection of two surfaces. The planner, based on that path definition along with a Cascaded control architecture and utilizing a nonlinear control technique for both control loops (position and attitude), creates a framework to manipulate the multicopters’ behaviors. The method is demonstrated to be able to generate a safe path taking into account obstacles perceived in real-time and avoids collisions. These algorithms are embedded in a software package to control the flight of a fully autonomous AscTec Firefly hexacopter with two cameras and onboard processing capabilities.  相似文献   
8.
Testosterone is the most important hormone in male health. Aging is characterized by testosterone deficiency due to decreasing testosterone levels associated with low testicular production, genetic factors, adiposity, and illness. Low testosterone levels in men are associated with sexual dysfunction (low sexual desire, erectile dysfunction), reduced skeletal muscle mass and strength, decreased bone mineral density, increased cardiovascular risk and alterations of the glycometabolic profile. Testosterone replacement therapy (TRT) shows several therapeutic effects while maintaining a good safety profile in hypogonadal men. TRT restores normal levels of serum testosterone in men, increasing libido and energy level and producing beneficial effects on bone density, strength and muscle as well as yielding cardioprotective effects. Nevertheless, TRT could be contraindicated in men with untreated prostate cancer, although poor findings are reported in the literature. In addition, different potential side effects, such as polycythemia, cardiac events and obstructive sleep apnea, should be monitored. The aim of our review is to provide an updated background regarding the pros and cons of TRT, evaluating its role and its clinical applicability in different domains.  相似文献   
9.
This paper analyzes some issues related to the metrological characterization of instruments for power quality monitoring, in order to move a step toward the definition of a full performance verification protocol. This protocol should include not only the test situations reported in corresponding standards, but also an array of different voltage and current fluctuations – linked to common power quality issues – that may be encountered in actual power systems. This performance analysis is particularly interesting because it can be found that different power quality instruments, fully meeting characteristics prescribed in standard, still may significantly disagree in some actual measurements. This is due for the existence of unresolved technical and theoretical issues related to the metrological characterization through the classical approaches of these instruments. The aim of the discussion carried out in this paper is also the specification of requirements of a test system devoted to calibration and verification of a power quality monitor, such as it is done in type testing. After a preliminary discussion about technical and theoretical issues related to the performance analysis of these instruments, a proposal of test protocol definition, with reference to some power quality phenomena and based on the design of experiment, is presented.  相似文献   
10.
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