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排序方式: 共有760条查询结果,搜索用时 500 毫秒
661.
Pawe Bryniarski Katarzyna Nazimek Janusz Marcinkiewicz 《International journal of molecular sciences》2022,23(3)
This review article is focused on antihypertensive drugs, namely angiotensin converting enzyme inhibitors (ACEI) and angiotensin II receptor blockers (ARB), and their immunomodulatory properties reported in hypertensive patients as well as in experimental settings involving studies on animal models and cell lines. The immune regulatory action of ACEI and ARB is mainly connected with the inhibition of proinflammatory cytokine secretion, diminished expression of adhesion molecules, and normalization of CRP concentration in the blood plasma. The topic has significant importance in future medical practice in the therapy of patients with comorbidities with underlying chronic inflammatory responses. Thus, this additional effect of immune regulatory action of ACEI and ARB may also benefit the treatment of patients with metabolic syndrome, allergies, or autoimmune disorders. 相似文献
662.
Urszula
widerska-Burek Margaret E. Daub Elizabeth Thomas Magdalena Jaszek Anna Pawlik Grzegorz Janusz 《International journal of molecular sciences》2020,21(22)
Phytopathogenic cercosporoid fungi have been investigated comprehensively due to their important role in causing plant diseases. A significant amount of research has been focused on the biology, morphology, systematics, and taxonomy of this group, with less of a focus on molecular or biochemical issues. Early and extensive research on these fungi focused on taxonomy and their classification based on in vivo features. Lately, investigations have mainly addressed a combination of characteristics such as morphological traits, host specificity, and molecular analyses initiated at the end of the 20th century. Some species that are important from an economic point of view have been more intensively investigated by means of genetic and biochemical methods to better understand the pathogenesis processes. Cercosporin, a photoactivated toxin playing an important role in Cercospora diseases, has been extensively studied. Understanding cercosporin toxicity in relation to reactive oxygen species (ROS) production facilitated the discovery and regulation of the cercosporin biosynthesis pathway, including the gene cluster encoding pathway enzymes. Furthermore, these fungi may be a source of other biotechnologically important compounds, e.g., industrially relevant enzymes. This paper reviews methods and important results of investigations of this group of fungi addressed at different levels over the years. 相似文献
663.
A metrological model for maximum expiration formulated by means of complex model reduction and selection of a parameter set for estimation was the purpose of this investigation. Reduction of the model was based on the forward-inverse method. Carrying out regression analysis showed that the properties of the airways were well approximated by exponential functions. The cross-sectional areas, airway lengths and compliances were replaced by these exponential relationships. Some other dependencies between mechanical quantities were also included. This reduced the number of parameters from 132 to 12. The complex and reduced models for maximal expiration were implemented on a PC and compared. The sensitivity index expressing the effect of parameter reduction was 3.2%. The selection of parameters for estimation was based on sensitivity analysis. This analysis showed that the reduced model was insensitive or weakly sensitive to eight parameters. This allowed for the selection of four parameters that influence the shape of the maximal expiration curve more than the others. 相似文献
664.
Janusz W. Sikora 《Polymer Engineering and Science》2001,41(9):1636-1643
A new mechanism is described that allows adjustment of the groove geometry in grooved feed extruders. This mechanism enables efficient, continuous and independent change of the groove geometry during the extrusion process. The patented solution of the activated grooved feed section enables one to change the number of grooves, taper angle and, connected with it, groove depth. The paper contains the graphical presentation of the selected results of experimental studies of autothermal extrusion of a medium density polyethylene in an extruder with the grooved feed section in which the groove taper angle, and thus groove depth, was changed during the extrusion process. The influence of changing the groove taper angle in the range from 0 to 5.236 × 10?2 rad and screw speeds ranging from 177 to 279 rev/min on extruder output was studied. The energy efficiency of the extruder was studied as well. 相似文献
665.
666.
The defect structure of CoO is considered, using defect activities instead of concentrations. The proposed model, based on the Debye-Hückel (D-H) theory, assumes only one type of predominant ionic lattice defect, i.e., doubly ionized cation vacancies. Application of the mass-action law to the formation of doubly ionized cobalt vacancies results in the following equilibrium constant: K ={ V n Co }{h˙ }2 / p O2 1/2 = 3 × 10−4 exp[−120.6 (kJ)/ RT ]. Using a modified Jonker's formalism, we have determined the equilibrium constant of the intrinsic electronic equilibrium: K i ={e'}{h˙ }= 12.8 exp[−3.0 (eV)/ kT ]. The width of the forbidden gap determined in this work is equal to E g = 3.0 – 2.2 × 10−4 T (eV). Good agreement between the proposed model and experimental data was found. 相似文献
667.
The 4:1 cluster model has been considered and its application to the available experimental data for the deviation from stoichiometry, electrical conductivity, and the Seebeck coefticient has been analyzed. It has been shown that the degree of ionization of the cluster is −5. The equilibrium constant of formation is K 5 = [( V Co )Co i ]5− [h˙ ]5 p O2 3/2 = 4.6 exp[−167.5 (kJ)/ RT ]. It has been shown that the applicability of this model in describing CoO properties is limited to higher values of the deviation from the stoichiometric composition (y). At low y , defects in CoO can be considered as isolated. Then doubly ionized cobalt vacancies are assumed to be the predominant lattice defects. Their equilibrium constant of formation, determined from experimental data in the vicinity of the Co/CoO phase boundary by using an ideal approximation, is K V = [ V n Co ][h˙ ]2 p o2 −1/2 = 3.2 × 10−4 exp[−121.1 (kJ)/ RT ]. Excellent agreement between the equilibrium constant K V determined for low p O 2 and that resulting from the Debye Hückel model within the entire range of y has been found. 相似文献
668.
Cezary Chojnacki Tomasz Poplawski Janusz Blasiak Jan Chojnacki Grazyna Klupinska 《International journal of molecular sciences》2013,14(6):12550-12562
Two clinical forms of functional dyspepsia (FD) are listed in the Rome III criteria: postprandial distress syndrome (PDS) and epigastric pain syndrome (EPS), differing in the recurrence of ailments depending on the diet. Continuous EPS (CEPS) is observed in some EPS patients, also at night, but its cause is still unknown. We showed previously that melatonin (MEL) homeostasis may be associated with FD. In the present work we evaluated selected components of melatonin homeostasis in patients with CEPS. The study included 30 patients with CEPS, 21 women and nine men, aged 21–49 years and 30 control subjects (EPS excluded); organic and mental diseases, as well as Helicobacter pylori infection, were excluded in both groups. The average severity of abdominal pain in the last three months was estimated in a 10-point scale (Visual Analog Scale). The levels of mRNA expression of arylalkylamine-N-acetyltransferase (AANAT) and hydroxyindole-O-methyltransferase (HIOMT), the main components of MEL homeostasis, were determined in gastric mucosa with real time PCR. The fasting serum level of MEL (at 09:00 a.m.) and circadian urine excretion of 6-sulfatoxymelatonin (6-HMS) were determined with ELISA. AANAT expression in antral mucosa of control subjects was 1.76 ± 0.41, in the gastric body 1.35 ± 0.38, and in the dyspeptic group 1.42 ± 0.38 (p < 0.05) and 0.92 ± 0.55 (p < 0.05), respectively. HIOMT expression in the control was 2.05 ± 0.70 in the antrum and 1.57 ± 0.69 in the body and in the CEPS group, it was: 1.51 ± 0.57 (p < 0.05) and 0.74 ± 0.31 (p < 0.001), respectively. MEL concentration (pg/mL) was 9.41 ± 3.09 in the control group and 5.62 ± 1.34 (p < 0.01) in the CEPS group. Urinary 6-HMS excretion (μg/24 h) was 11.40 ± 4.46 in the controls and 7.68 ± 2.88 (p < 0.05) in the CEPS. Moreover, a negative correlation was found between the tested parameters and severity of epigastric pain. These results indicate that patients with CEPS may display low level of AANAT and HIOMT expression in gastric mucosa, resulting in decreased MEL synthesis. 相似文献
669.
Janusz Lewi
ski Iwona Justyniak Janusz Lipkowski Janusz Zachara 《Inorganic chemistry communications》2000,3(12)
The X-ray structure analysis of [Et2In(μ,λ-O2C)–C6H4–2–NH2]n (1) reveals an extended one-dimensional chain comprised of an array of five-coordinate indium centers. The chain unit repeated along two-fold screw axis is defined by the diethylindium moiety chelated asymmetrically by the carboxylate group with one of the two carboxylate oxygens acting as bridge to the next indium center in the chain. The NH2 group does not participate in the coordination of the metal center but is involved in an intermolecular hydrogen bond. 相似文献
670.
Janusz Konrad 《Communications Magazine, IEEE》2007,45(1):34-42
Network camera, made possible by recent advances in the integration of sensing, compression, and communication hardware, is a new video source that can be easily deployed and remotely managed. Unobtrusively located along highways, at airports, or in office buildings, such cameras can form a visual sensor network, or camera web, an extremely rich source of visual information. In its infancy today, camera web deployment will likely accelerate in the future and one can expect visual sensing devices to eventually become as ubiquitous as electric bulbs. While the capturing hardware has evolved tremendously, hardware and algorithms necessary for effective analysis and efficient communication of multi-camera data clearly lag. In this article, I overview one particular aspect of visual data analysis, namely, space-time video segmentation that is often a pre-requisite for motion estimation, video compression, event detection, scene understanding, etc. I introduce the concept of object tunnel, a 3-D surface in space-time through which a video object travels, and the associated concept of occlusion volume. I present examples of object tunnels and occlusion volumes on surveillance data that, upon further processing, may lead to automatic event detection or scene understanding. Finally, I describe challenges in extending video analysis algorithms to visual sensor networks, and I outline some possible approaches 相似文献