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81.
Fine‐needle aspiration biopsy (FNAB) is a useful technique in the evaluation of central lung tumors which is commonly encountered in clinical cytology practice. Some of these tumors may show endobronchial, polypoid growth which is readily apparent to the endoscopist. Pulmonary salivary gland‐type tumors and carcinoid tumors are overall uncommon in the lung, but these tumors tend to occur centrally and show endobronchial involvement. The prognosis of these tumors is generally better than that of small cell or non‐small cell carcinomas of the lung and more conservative surgical resection is often indicated. The identification of salient cytological features and a high index of suspicion when considering the differential diagnosis of a central lung tumor is essential to accurate diagnosis. This review focuses on cytological clues as well as ancillary techniques that may be useful to the practicing cytopathologist. 相似文献
82.
Pawel Zochowski Marcin Bajkowski Roman Grygoruk Mariusz Magier Wojciech Burian Dariusz Pyka Miroslaw Bocian Krzysztof Jamroziak 《Materials》2022,15(1)
This article presents an analysis of the effectiveness of available numerical techniques in mapping the characteristic behavior of ballistic ceramics under projectile impact conditions. As part of the work, the ballistic tests were performed on the layered ceramic/steel composite armor and tested with the 7.62 × 39 mm, armor-piercing incendiary (API) BZ projectile. The experimental tests were then mapped using computer simulations. In numerical analyses, four different techniques were used to describe cubic ceramic tiles Al2O3 placed on the ARMOX 500T steel backing plate, i.e.,: the Finite Element Method without Erosion (FEM), Finite Element with erosion (FEM + Erosion), Smoothed Particles Hydrodynamics (SPH) and a hybrid method that converts finite elements to SPH particles after exceeding the defined failure criteria (FEM to SPH conversion). The effectiveness of the individual methods was compared in terms of quality (mapping of characteristic phenomena occurring during the penetration process), quantity (bulge height of the backing plate) and time needed to complete the calculations. On the basis of the results of the experiments and numerical simulations, it was noticed that the most accurate reproduction of the phenomenon of ballistic impact of AP projectiles on ceramic/steel composite armor can be obtained by using a hybrid method, incorporating the conversion of finite elements into SPH particles. This method should be used in cases where accuracy of the results is more important than the time required to complete the calculations. In other situations where the purpose of the calculation is not to determine, for example, the exact value of penetration depth but only to observe a certain trend, the FEM method with defined erosion criteria (variant 2), which is more than 10 times faster, can be successfully used. 相似文献
83.
Elizabeth A. Lawson Pawel K. Olszewski Aron Weller James E. Blevins 《Journal of neuroendocrinology》2020,32(4)
Obesity and its associated complications have reached epidemic proportions in the USA and also worldwide, highlighting the need for new and more effective treatments. Although the neuropeptide oxytocin (OXT) is well recognised for its peripheral effects on reproductive behaviour, the release of OXT from somatodendrites and axonal terminals within the central nervous system (CNS) is also implicated in the control of energy balance. In this review, we summarise historical data highlighting the effects of exogenous OXT as a short‐term regulator of food intake in a context‐specific manner and the receptor populations that may mediate these effects. We also describe what is known about the physiological role of endogenous OXT in the control of energy balance and whether serum and brain levels of OXT relate to obesity on a consistent basis across animal models and humans with obesity. We describe recent data on the effectiveness of chronic CNS administration of OXT to decrease food intake and weight gain or to elicit weight loss in diet‐induced obese (DIO) and genetically obese mice and rats. Of clinical importance is the finding that chronic central and peripheral OXT treatments both evoke weight loss in obese animal models with impaired leptin signalling at doses that are not associated with visceral illness, tachyphylaxis or adverse cardiovascular effects. Moreover, these results have been largely recapitulated following chronic s.c. or intranasal treatment in DIO non‐human primates (rhesus monkeys) and obese humans, respectively. We also identify plausible mechanisms that contribute to the effects of OXT on body weight and glucose homeostasis in rodents, non‐human primates and humans. We conclude by describing the ongoing challenges that remain before OXT‐based therapeutics can be used as a long‐term strategy to treat obesity in humans. 相似文献
84.
Functional connectivity among brain regions has been investigated via an analysis of correlations between regional signal fluctuations recorded in magnetic resonance (MR) images obtained in a steady state. In comparison with studies of functional connectivity that utilize task manipulations, the analysis of correlations in steady state data is less susceptible to confounds arising when functionally unrelated brain regions respond in similar ways to changes in task. A new approach to identifying interregional correlations in steady state data makes use of two independent data sets. Regions of interest (ROIs) are defined and hypotheses regarding their connectivity are generated in one data set. The connectivity hypotheses are then evaluated in the remaining (independent) data set by analyzing low frequency temporal correlations between regions. The roles of the two data sets are then reversed and the process repeated, perhaps multiple times. This method was illustrated by application to the language system. The existence of a functional connection between Broca's area and Wernicke's area was confirmed in healthy subjects at rest. An increase in this functional connection when the language system was actively engaged (when subjects were continuously listening to narrative text) was also confirmed. In a second iteration of analyses, a correlation between Broca's area and a region in left premotor cortex was found to be significant at rest and to increase during continuous listening. These findings suggest that the proposed methodology can reveal the presence and strength of functional connections in high-level cognitive systems. 相似文献
85.
Dewald O Zymek P Winkelmann K Koerting A Ren G Abou-Khamis T Michael LH Rollins BJ Entman ML Frangogiannis NG 《Circulation research》2005,96(8):881-889
The CC chemokine Monocyte Chemoattractant Protein (MCP)-1/CCL2 has potent mononuclear cell chemo-attractant properties, modulates fibroblast and endothelial cell phenotype and may play an important role in wound healing. In order to examine whether MCP-1 critically regulates myocardial infarct healing, we studied the effects of MCP-1 gene disruption and antibody neutralization in a closed-chest model of reperfused murine myocardial infarction. MCP-1-/- mice had decreased and delayed macrophage infiltration in the healing infarct and demonstrated delayed replacement of injured cardiomyocytes with granulation tissue. In contrast, the time course and density of neutrophil infiltration was similar in MCP-1 null and wild-type animals. MCP-1-/- infarcts had decreased mRNA expression of the cytokines TNF-alpha, IL-1beta, TGF-beta2, -beta3, and IL-10 and demonstrated defective macrophage differentiation evidenced by decreased Osteopontin-1 expression. MCP-1 deficiency diminished myofibroblast accumulation but did not significantly affect infarct angiogenesis. Despite showing delayed phagocytotic removal of dead cardiomyocytes, MCP-1-/- mice had attenuated left ventricular remodeling, but similar infarct size when compared with wild-type animals. MCP-1 antibody inhibition resulted in defects comparable with the pathological findings noted in infarcted MCP-1-/- animals without an effect on macrophage recruitment. MCP-1 has important effects on macrophage recruitment and activation, cytokine synthesis and myofibroblast accumulation in healing infarcts. Absence of MCP-1 results in attenuated post-infarction left ventricular remodeling, at the expense of a prolonged inflammatory phase and delayed replacement of injured cardiomyocytes with granulation tissue. 相似文献
86.
Jaroslaw Bilinski Karol Lis Agnieszka Tomaszewska Aleksandra Pechcinska Pawel Grzesiowski Tomasz Dzieciatkowski Alicja Walesiak Beata Gierej Bogna Ziarkiewicz‐Wrblewska Martyna Tyszka Piotr Kacprzyk Lidia Chmielewska Anna Waszczuk‐Gajda Wieslaw Wiktor‐Jedrzejczak Grzegorz W. Basak 《Transplant infectious disease》2021,23(1):e13386
Fecal microbiota transplantation (FMT) was performed to decolonize gastrointestinal tract from antibiotic‐resistant bacteria before allogeneic hematopoietic cells transplantation (alloHCT). AlloHCT was complicated by norovirus gastroenteritis, acute graft‐versus‐host disease, and eosinophilic pancolitis. Norovirus was identified in samples from FMT material. Symptoms resolved after steroids course and second norovirus‐free FMT from another donor. 相似文献
87.
Recombination-activating gene (RAG)1 and RAG2 encode T and B lymphocyte-specific endonucleases indispensable for rearrangements of antigen-receptor gene segments but also capable of causing deleterious chromosome rearrangements. The mechanisms regulating RAG expression and repression are not clear. Here we identify NWC, a third evolutionarily conserved gene within the RAG locus, and show that it is ubiquitously expressed, with the notable exception of RAG-nonexpressing immature and mature T and B lymphocytes because in lymphocytes it is regulated by the RAG1 promoter and transcribed as RAG1-NWC hybrid mRNA molecules. We also show that in all other cells NWC is controlled by the RAG2 intragenic promoter, which in immature and mature T and B lymphocytes is silent. The possible implications of these findings for understanding the activation and inactivation of RAG genes in lymphocytes and their repression in other cells are discussed. 相似文献
88.
The aim of this review is to present the recent developments in heat pipe production, which respond to the current technical problems related to the wide implementation of this technology. A novel approach in HP manufacturing is to utilise hi-tech additive manufacturing techniques where the most complicated geometries are fabricated layer-by-layer directly from a digital file. This technology might be a solution to various challenges that exist in HP production, i.e., (1) manufacturing of complex or unusual geometries HPs; (2) manufacturing complicated and efficient homogenous wick structures with desired porosity, uniform pore sizes, permeability, thickness and where the pores are evenly distributed; (3) manufacturing a gravity friendly wick structures; (4) high customisation and production time; (5) high costs; (6) difficulties in the integration of the HP into a unit chassis that enables direct thermal management of heated element and decrease its total thermal resistance; (7) high weight and material use of the part; (8) difficulties in sealing; (9) deformation of the flat shape HPs caused by the high pressure and uneven distribution of stress in the casing, among others. 相似文献
89.
Kochman W Dobrzycki S Nowak KS Chlopicki S Kralisz P Prokopczuk P Bachorzewska-Gajewska H Gugala K Niewada M Mezynski G Poniatowski B Korecki J Musial WJ 《Journal of thrombosis and thrombolysis》2004,17(2):127-131
BACKGROUND: Intravenous glycoprotein GP IIb/IIIa receptor antagonists administered to patients with acute coronary syndromes limit platelet-dependent thrombus formation and vasoconstriction and lower the complication rate of PCI. The efficacy of glycoprotein IIb/IIIa inhibitors critically depends on appropriate suppression of platelet aggregation. A growing body of evidence indicates that regimen of tirofiban used in several recent trials may be suboptimal. We investigated if a novel regimen of dosage of tirofiban administered to patients with acute myocardial infarction with ST elevation (STEMI) before primary angioplasty is safe, feasible and whether such treatment improves coronary flow in infarct-related artery. METHODS: It was an open-label, non-randomized, prospective observational study. 253 consecutive patients with STEMI, qualified to PCI were included. 104 of patients (group 1) received heparin plus tirofiban at a novel regimen (10 microg/kg bolus, followed by 0.4 microg/kg/min for 30 min and then 0.1 microg/kg/min for 12-24 hours) and the remaining 149 of the patients (group 2) received a standard dose of heparin prior to PCI. Bleeding complications were recorded. The primary end point of the study was combined TIMI 1 + 2 + 3 grade flow at the time of first contrast medium injection during angiography for primary PCI. RESULTS: Heparin was administered 50.3 +/- 58.1 minutes (group 1) or 62.3 +/- 67.3 minutes (group 2) ( p = 0.205). Tirofiban was administered for an average of 14.5 +/- 14.4 minutes before TIMI assessment (group 1). In patients treated with heparin + tirofiban the rate of combined TIMI 1 + 2 + 3 coronary flow was higher (38.4% vs. 24.8%, p = 0.020) as compared to patients treated with heparin alone. The difference in the rate of TIMI > or = 2 coronary blood flow between the groups 1 and 2 (24.0% vs. 20.1%) has not reached statistical significance ( p = 0.459). At the same time the significant difference in the rate of TIMI 1 coronary blood flow between the groups 1 and 2 was noted (14.4 vs. 4.7%, p = 0.007). In hospital mortality in the groups 1 and 2 was similar (5.3 vs. 4.8%, p = 0.838). Significant difference was noted between the groups 1 and 2 with regard to minor bleeding complications (17.3 vs. 8.7%, p = 0.041). CONCLUSION: In patients undergoing primary angioplasty for acute myocardial infarction the novel regimen of tirofiban is well tolerated and feasible, and is associated with improvement in coronary blood flow in the infarct related artery. Larger studies assessing the effects of tirofiban on clinical outcomes of patients with AMI undergoing primary angioplasty seem worthwhile. 相似文献
90.
Stanislaw Pogorzelski Katarzyna Boniewicz-Szmyt Maciej Grzegorczyk Pawel Rochowski 《Materials》2022,15(5)
The aim of the work was to quantify the surface wettability of metallic (Fe, Al, Cu, brass) surfaces covered with sprayed paints. Wettability was determined using the contact angle hysteresis approach, where dynamic contact angles (advancing ΘA and receding ΘR) were identified with the inclined plate method. The equilibrium, ΘY, contact angle hysteresis, CAH = ΘA − ΘR, film pressure, Π, surface free energy, γSV, works of adhesion, WA, and spreading, WS, were considered. Hydrophobic water/solid interactions were exhibited for the treated surfaces with the dispersive term contribution to γSV equal to (0.66–0.69). The registered 3D surface roughness profiles allowed the surface roughness and surface heterogeneity effect on wettability to be discussed. The clean metallic surfaces turned out to be of a hydrophilic nature (ΘY < 90°) with high γSV, heterogeneous, and rough with a large CAH. The surface covering demonstrated the parameters’ evolution, ΘA↑, ΘR↑, γSV↓, WA↓, and WS↓, corresponding to the surface hydrophobization and exhibiting base substratum-specific signatures. The dimensionless roughness fluctuation coefficient, η, was linearly correlated to CAH. The CAH methodology based on the three measurable quantities, ΘA, ΘR, and liquid surface tension, γLV, can be a useful tool in surface-mediated process studies, such as lubrication, liquid coating, and thermoflow. 相似文献