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81.
82.
This research tests energy optimised furnace (EOF) steel slag as substitution for natural coarse aggregate in concrete. Steel slag’s usefulness as a substitute for natural coarse aggregate in concrete is the primary goal of this research. According to IS:2386-1963, the characterization of EOF steel slag, as coarse, is done by examining the shape and size of a particle, mechanical properties, physical properties, soundness, and alkali-aggregate reactivity. Tests for detection of staining material in steel slag and hardness of inter-facial transition zone in hardened cement paste were also carried out. The chemical analysis of the steel slag reveals the stability of oxides present in the steel slag. Microstructural characterization by SEM (scanning electron microscope) analysis of steel slag aggregate was also employed to support the characterization and XRD analysis, and it was found that the EOF steel slag is crystalline. The digital image processing technique (DIP) is adopted to study the shape indices, circularity, sphericity, shape factor, and roundness of natural and EOF steel slag aggregate. According to the characterization and strength investigation, steel slag aggregate outperforms natural coarse aggregate.  相似文献   
83.
The characteristics of a concrete mix are purely dependent on the hydration of cement that is carried forward by using the water quality used in the mix. Several researchers have focused on incorporating pozzolanic or nanomaterials to improve the hydration mechanisms and impart high strength to concrete. A new technology has been introduced to improve the properties of concrete by magnetic-field-treated water (MFTW). Due to magnetization, water particles become charged and the molecules inside the water cluster decrease from 13 to 5 or 6, which eventually decreases the hardness of water, thus improving the strength of concrete when compared to the use of normal water (NW). In advanced construction techniques and practices, the application of Magnetic Water (MW) plays an important role in boosting physicochemical properties. This research work focused on evaluating the standards of water quality through physiochemical analysis, such as Electrical Conductivity (EC), Viscosity, pH, and Total Dissolved Solids (TDS) with the MW at different exposure periods (60 min (MW60), 45 min (MW45), 30 min (MW30), 15 min (MW15), and instant exposure (MWI)). Experiments were carried out to evaluate the fresh, hardened, and microstructural behavior of concrete made with magnetic water (MW) using a permanent magnet of PERMAG (N407) under a field intensity of 0.9 Tesla. In addition, optical properties such as X-ray Diffraction (XRD) and Ultraviolet (UV) absorption were considered for the MW60 mix to ensure water magnetization. Characterization methods such as Fourier Transform Infrared Spectroscopy (FT-IR), Thermogravimetric Analysis (TGA), and Scanning Electron Microscopy (SEM) were employed for NWC and MWC to quantify the hydrated products. From the results, it was observed that the magnetic effect on water characteristics showed significant improvement in the concrete properties with the increase in exposure duration. There were increments of 25.6% and 24.1% in workability and compressive strength, respectively, for the MW60 mix compared to normal water concrete (NWC).  相似文献   
84.
Although the collecting duct is regarded as the primary site at which mineralocorticoids regulate renal sodium transport in the kidney, recent evidence points to the distal convoluted tubule as a possible site of mineralocorticoid action. To investigate whether mineralocorticoids regulate the expression of the thiazide-sensitive Na–Cl cotransporter (TSC), the chief apical sodium entry pathway of distal convoluted tubule cells, we prepared an affinity-purified, peptide-directed antibody to TSC. On immunoblots, the antibody recognized a prominent 165-kDa band in membrane fractions from the renal cortex but not from the renal medulla. Immunofluorescence immunocytochemistry showed TSC labeling only in distal convoluted tubule cells. Semiquantitative immunoblotting studies demonstrated a large increase in TSC expression in the renal cortex of rats on a low-NaCl diet (207 ± 21% of control diet). Immunofluorescence localization in tissue sections confirmed the strong increase in TSC expression. Treatment of rats for 10 days with a continuous subcutaneous infusion of aldosterone also increased TSC expression (380 ± 58% of controls). Furthermore, 7-day treatment of rats with an orally administered mineralocorticoid, fludrocortisone, increased TSC expression (656 ± 114% of controls). We conclude that the distal convoluted tubule is an important site of action of the mineralocorticoid aldosterone, which strongly up-regulates the expression of TSC.  相似文献   
85.
Human leukocyte-associated Ig-like receptor-1 (LAIR-1) is a transmembrane glycoprotein with a single extracellular Ig-like domain and a cytoplasmic tail containing two immunoreceptor tyrosine-based inhibition motifs (ITIMs). It is constitutively expressed on the majority of human mononuclear leukocytes and functions as an inhibitory receptor. In this study, we show that freshly isolated peripheral blood T cells are heterogeneous in their expression levels of LAIR-1. We have found that naive T cells express the highest levels of LAIR-1, even more than memory cells. The cross-linking of LAIR-1 inhibits T cell receptor (TCR) mediated signals in freshly isolated human naive T cells and whole populations of CD4+ or CD8+ T cells. TCR cross-linking increased cell surface expression of LAIR-1 in a process that requires p38 MAP kinase and ERK signaling. Altogether, these results indicate that LAIR-1 is capable of negatively regulating T cell functions, and its high level of expression by naive T cells suggests that it may function at an early stage in the development of an immune response.  相似文献   
86.
Complement receptor II (CR2) also known as CD21 is the receptor for C3d on immune complexes. In humans it serves as a receptor for the Epstein-Barr virus (EBV). CR2 is expressed on B cells and in low density in the T cell lineage. EBV can infect T cells and EBV-positive T lymphomas have been described. Although CR2 mRNA is readily detectable in T cells, the function of CR2 in human T lymphocytes remains elusive. Here we have analyzed the expression of CR2 in normal and activated T cells. PCR analyses and immunofluorescence/confocal microscopy of peripheral blood T cells and of activated T cells shows considerable reduction in CR2 mRNA and protein expression upon activation. The downregulation of CR2 expression may modulate life span or immunological reactivity of T cells and the susceptibility of cells to infection by lymphotropic viruses.  相似文献   
87.
IntroductionAutoimmune disorders are chronic, self-mediated, misdirected immune responses against their own immune system. It required intensive, complex and costly drug treatment regimen increased the risk of pharmacotherapy error and adversely affects patients. Hence, pharmacist care will have vital roles in autoimmune disorders to achieve health related outcomes.ObjectivesThis review aimed to gather evidence on the impact of pharmacist care on clinical, humanistic and economic outcomes, adherence to medications, and drug related problems in the management of autoimmune disorders among the usual care group.MethodologyA comprehensive review conducted in compliance with the PRISMA statement and systematic search was performed across five databases included PubMed Central, Web of Sciences, Scopus, Cochrane Library and google scholar from inception until August 2020. This research included full-text articles of randomized and non-randomized studies that evaluated impact of pharmacist care in autoimmune disorders.ResultsA total of nine studies were included (seven RCTs and two non-RCTs), including 829 patients with autoimmune disorders. A total of four studies (80%) show an enhancement in at least one clinical parameter due to pharmacist care. A substantial improvement in at least one humanistic parameter observed in all five studies (100%). While four out of five studies (80%) clearly displayed a remarkable improvement in medication adherence in the pharmacist care group from baseline to the completion of follow-ups. One study quantified a 99.08% resolution of DRPs in the pharmacist care group. Another study estimated the cost of medical resources uses per patient and found no difference in cost-effectiveness over six months between groups.ConclusionThis review reinforces the vital contribution of pharmacists to achieve clinical outcomes, humanistic outcomes, adherence to medications and DRPs in the efficient management of autoimmune disorders. However, no notable changes in economic outcomes were observed in this review.  相似文献   
88.
Mesenchymal stromal cells (MSCs) are cells with the characteristic ability of self-renewal along with the ability to exhibit multilineage differentiation. Bone marrow (BM) is the first tissue in which MSCs were identified and BM-MSCs are most commonly used among various MSCs in clinical settings. MSCs can stimulate and promote osseous regeneration. Due to the difference in the development of long bones and craniofacial bones, the mandibular-derived MSCs (M-MSCs) have distinct differentiation characteristics as compared to that of long bones. Both mandibular and long bone-derived MSCs are positive for MSC-associated markers such as CD-73, -105, and -106, stage-specific embryonic antigen 4 and Octamer-4, and negative for hematopoietic markers such as CD-14, -34, and -45. As the M-MSCs are derived from neural crest cells, they have embryogenic cells which promote bone repair and high osteogenic potential. In vitro and in vivo animal-based studies demonstrate a higher rate of proliferation and high osteogenic potential for M-MSCs as compared to long-bones MSCs, but in vivo studies in human subjects are lacking. The BM-MSCs have their advantages and limitations. M-MSCs may be utilized as an alternative source of MSCs which can be utilized for tissue engineering and promoting the regeneration of bone. M-MSCs may have potential advantages in the repair of craniofacial or orofacial defects. Considering the utility of M-MSCs in the field of orthopaedics, we have discussed various unresolved questions, which need to be explored for their better utility in clinical practice.  相似文献   
89.
Chronic lymphocytic inflammation with pontine perivascular enhancement responsive to steroids (CLIPPERS) is a recently described inflammatory disease of central nervous system with distinct clinical and radiological features. The etiopathogenesis of this rare entity remains to be understood. The histopathological findings closely resemble chronic inflammatory diseases like sarcoidosis and malignancies like lymphoma. With advancements in serology, immunopathology and radiology CLIPPERS is identified as a distinct entity that differs considerably in its clinical presentation, immunopathology, radiological findings and response to steroids. We describe a case that presented to us with progressive quadriparesis and lower cranial nerve deficits whose radiological and pathological findings were consistent with CLIPPERS. The patient had a good outcome with long term immunosuppression.  相似文献   
90.
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