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71.
This study aims to develop highly durable, mineral carbonation-based, resource-recycling, secondary cement products based on supercritical carbon dioxide (CO2) curing as part of carbon capture utilization technology that permanently fixes captured CO2. To investigate the basic characteristics of secondary cement products containing concrete sludge waste (CSW) as the main materials after supercritical CO2 curing, the compressive strengths of the paste and mortar (fabricated by using CSW as the main binder), ordinary Portland cement, blast furnace slag powder, and fly ash as admixtures were evaluated to derive the optimal mixture for secondary products. The carbonation curing method that can promote the surface densification (intensive CaCO3 formation) of the hardened body within a short period of time using supercritical CO2 curing was defined as “Lean Carbonation”. The optimal curing conditions were derived by evaluating the compressive strength and durability improvement effects of applying Lean Carbonation to secondary product specimens. As a result of the experiment, for specimens subjected to Lean Carbonation, compressive strength increased by up to 12%, and the carbonation penetration resistance also increased by more than 50%. The optimal conditions for Lean Carbonation used to improve compressive strength and durability were found to be 35 °C, 80 bar, and 1 min. 相似文献
72.
Caon Thiago Jin Liang Simões Cláudia M. O. Norton Raymond S. Nicolazzo Joseph A. 《Pharmaceutical research》2015,32(1):1-21
Pharmaceutical Research - With continuing advances in biotechnology and genetic engineering, there has been a dramatic increase in the availability of new biomacromolecules, such as peptides and... 相似文献
73.
Ten new sesterterpene compounds (4-13) and seven known metabolites (1-3, 14-17) were isolated from the sponge Smenospongia sp. collected from Korean coastal waters. On the basis of combined spectroscopic analyses, the new compounds exhibited diverse functionalities on a common scalarane sesterterpene structure. The presence of a 23-aldehyde on compound 6 and a 20-carboxylic acid on 11 is unprecedented among sponge-derived scalarane sesterterpenes. Several of the new compounds showed significant cytotoxicity and antimicrobial activity, as well as moderate inhibitory activity against isocitrate lyase. 相似文献
74.
75.
Pereira Fontes TM Santos Simões R Martins Oliveira FH de Jesus Simões Ms Oliveira-Filho RM Nakamura MU Kulay L 《Clinical and experimental obstetrics & gynecology》2007,34(3):175-178
The purpose of the study was to evaluate at term, the effects of the association of zidovudine/ritonavir administered during the entire period of rat pregnancy. Forty pregnant EPM-1 Wistar rats were divided randomly into four groups: one control (drug vehicle control, n=10) and three experimental treated with an oral solution of zidovudine/ritonavir (Exp 1 = 10/20 mg/kg bw, n = 10; Exp 2 = 30/60 mg/kg bw, n=10; Exp 3 = 90/180 mg/kg bw, n=10) from day 0 up to day 20 of pregnancy. Maternal body weights were recorded at the start of the experiment and at the 7th, 14th and the 20th day thereafter. At term (20th day) the rats were anesthetized and, upon laparotomy and hysterotomy, the number of implantations, resorptions, living fetuses, placentae and intrauterine deaths were recorded. The collected fetuses and placentae were weighed, and the concepts were examined under a stereoscopic microscope for external malformations. The maternal body gain and the mean fetal weight at term were both significantly lower (p < 0.01 and p < 0.0001, respectively) in the experimental groups compared to the control. The recorded resorptions were higher in Exp 2 and Exp 3 groups than in the control group. The other parameters were not affected. The exposure of pregnant rats at term to a 1:2 association of zidovudine plus ritonavir resulted in a significant reduction in maternal body weight gain and increased rate of fetal resorption. 相似文献
76.
Morphological and biochemical appraisal of the liver and renal effects of indinavir on rat pregnancy
Quintino MP Simões RS Oliveira FH Oliveira-Filho RM Simões MJ Nakamura MU Kulay L 《Clinical and experimental obstetrics & gynecology》2007,34(4):232-235
Since indinavir is currently used in combination with other antiretroviral agents, there is a scarcity of studies in the literature on its single-drug perinatal safety. Thus, we decided to examine the gross maternal and fetal effects of indinavir administered alone during the entire period of rat pregnancy. Forty pregnant animals were assigned at random to four groups (C = control) treated with the drug vehicle (distilled water); the experimental groups were treated with indinavir as follows: E1 = 40 mg/kg; E2 = 120 mg/kg; E3 = 360 mg/kg from "zero" up to the 20th day of gestation. Drug or vehicle were administered daily by gavage. Each group consisted of ten animals. At term-pregnancy, the rats were deeply anesthetized and blood samples were collected for alanine aminotransferase (ALT) and aspartate aminotransferase (AST), creatinine and urea determinations. Fragments of maternal and fetal livers and kidneys were taken and routinely processed for histopathological study. Serum ALT activity in the E2 group was significantly higher (p < 0.01) than that of the other groups. The concentration of creatinine in blood was lower in the E2 and E3 groups than in group E1 (p < 0.01), whereas blood urea in group E3 was significantly lower than in the other groups (p < 0.01). Morphological (light microscopy) studies revealed that no significant effects of the drug could be detected regarding either maternal or fetal organs of the E1 and E2 groups. However, the maternal hepatocytes in the E3 group showed heterochromatic nuclei. In addition, there was some fatty infiltration, congested sinusoids and portal dilation. Maternal kidneys in the E2 and E3 groups revealed vascular dilation around the convoluted tubules. Regarding the biochemical determinations, the alterations observed were mild, without biological relevance, thus indicating that the treatment with indinavir during the entire gestation was essentially devoid of hepatic or renal effects which could result in altered metabolic parameters. It is concluded that indinavir was well tolerated in therapeutic and even in 9-fold higher doses. Notwithstanding, discrete morphological alterations occurred in the maternal compartment, but with no functional expression that could indicate deleterious effects on mothers and/or fetuses. 相似文献
77.
78.
Ji Hwan Lee Ji Hoon Kim Incheol Park Hyun Sim Lee Joon Min Park Sung Phil Chung Hyeon Chang Kim Won Jeong Son Yun Ho Roh Min Joung Kim 《Yonsei medical journal》2022,63(5):470
PurposeAccess block due to the lack of hospital beds causes crowding of emergency departments (ED). We initiated the “boarding restriction protocol” that limits the time of stay in the ED for patients awaiting hospitalization to 24 hours from arrival. The purpose of this study was to determine the effect of the boarding restriction protocol on ED crowding.Materials and MethodsThe primary outcome was ED occupancy rate, which was calculated as the ratio of the number of occupying patients to the total number of ED beds. Time factors, such as length of stay (LOS), treatment time, and boarding time, were investigated.ResultsThe mean of the ED occupancy rate decreased from 1.532±0.432 prior to implementation of the protocol to 1.273±0.353 after (p<0.001). According to time series analysis, the absolute effect caused by the protocol was -0.189 (-0.277 to -0.110) (p=0.001). The proportion of patients with LOS exceeding 24 hours decreased from 7.6% to 4.0% (p<0.001). Among admitted patients, ED LOS decreased from 770.7 (421.4–1587.1) minutes to 630.2 (398.0–1156.8) minutes (p<0.001); treatment time increased from 319.6 (198.5–482.8) minutes to 344.7 (213.4–519.5) minutes (p<0.001); and boarding time decreased from 298.9 (109.5–1149.0) minutes to 204.1 (98.7–545.7) minutes (p<0.001). In pre-protocol period, boarding patients accumulated in the ED during the weekdays and resolved on Friday, but this pattern was alleviated in post-period.ConclusionThe boarding restriction protocol was effective in alleviating ED crowding by reducing the accumulation of boarding patients in the ED during the weekdays. 相似文献
79.
There are various changes in the thyroid gland and its function in chronic renal failure (CRF). These changes include lower levels of circulating thyroid hormone, altered peripheral hormone metabolism, decreased binding to carrier proteins, possible reduction in tissue hormone content, and increased iodine storage in the thyroid gland. The decrease of excretion of urinary iodine in CRF increases serum inorganic iodine level and iodine content of the thyroid, which consequently enlarges the gland. This study is designed to investigate the prevalence of goiter and thyroid dysfunction in patients with end-stage renal disease (ESRD) on hemodialysis (HD) in an iodine-deficient community. Eighty-seven (40 females and 47 males) HD patients and 169 (79 females and 90 males) healthy individuals as controls are included. Sex ratios for the patient and control groups are 0.85 and 0.88, respectively. Mean ages for the patient and control groups are 42.94 +/- 11.88 and 40.20 +/- 10.72 years, respectively. Examination of the thyroid gland using ultrasonography along with simultaneous measurement of blood levels of free-T4 (FT4), free-T3 (FT3), and thyrotropin (TSH) are made for every individual. The presence of goiter demonstrable by ultrasonography is found in 32.2% of the uremic patients and in 23.5% of the controls and its prevalence increases with age (P = 0.01). In 32 (36.8%) of the patients and 29 (17.1%) of the controls at least one thyroid nodule is found in ultrasonography. Between patients with or without a nodular goiter the authors could not observe any difference for duration of dialysis and serum levels of TSH, FT4, FT3, calcium, and albumin. In ESRD patients the prevalence of nodular goiter is higher for females (47.5% vs. 27.7%, P = 0.045) and increases with age (P = 0.04). Though incidence of hyperthyroidism is found to be similar for the two groups (1.14% in ESRD patients vs. 1.10% in controls), hypothyroidism is observed in 3.4% of ESRD patients but only 0.6% of controls. This high incidence of hypothyroidism and nodular goiter in ESRD patients shows that screening for thyroid dysfunction and goiter, using appropriate laboratory tests and ultrasonography, should be considered in evaluation of every ESRD patient. 相似文献
80.
Isabel G. Quirino Jose Silverio S. Diniz Maria Candida F. Bouzada Alamanda K. Pereira Thais J. Lopes Gabriela M. Paix?o Natalia N. Barros Luisa C. Figueiredo Antonio Carlos V. Cabral Ana Cristina Sim?es e Silva Eduardo A. Oliveira 《Clinical journal of the American Society of Nephrology》2012,7(3):444-451