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81.
4,4′-(1,4-phenylene)bis(2-(alkylamino)-3-nitro-4H-benzo[g]chromene-5,10-dione) and 4,4′-(1,4-phenylene)bis(2-(alkylamino)-3-nitropyrano[3,2-c]chromen-5(4H)-one) derivatives are synthesized by a one-pot, multi-component reaction of N-alkyl-1-(methylthio)-2-nitroethenamine (derived from the reaction of various amines and 1,1-bis(methylthio)-2-nitroethene) with terephthalaldehyde or isophthalaldehyde, and 2-hydroxy-1,4-naphthoquinone or 4-hydroxycoumarin in EtOH/H2O (85 : 15) as the solvent at 89 °C. Response surface methodology (RSM) is used to investigate the effect of reaction temperature and water content of aqueous ethanol on the product yields and reaction time. The notable features of this work are the optimization of reaction conditions with minimal experiments, absence of catalyst, good yields, simple work-up and the non-chromatographic purification of products.One-pot synthesis of C2-symmetric chromene derivatives, which serve as building blocks to prepare liquid crystals with potential electrical or optical properties. 相似文献
82.
Ahmad Reza Hosseini Ruholla Rahimi Ali Taheri Mirghaed 《Comparative clinical pathology》2014,23(3):775-778
In this study, the histamine concentration in the muscle tissue of whole rainbow trout (Oncorhynchus mykiss) was monitored during ice storage for a period of 18 days (0, 3, 6, 9, 12, 15 and 18th day). Results showed that the concentration of histamine increased linearly (P?<?0.05) during ice storage (except the 18th day). Histamine was not detected at the first and third day of storage. The first detection of histamine was in the sixth storage day. Initial concentration of histamine was 1.09 μg/g and finally reached to 4.30 μg/g. The maximum histamine levels was reported to be below the Australian Food Standards Code (2001) safe level (200 mg/kg), and histamine levels were low even after 18 days of storage and remained below the Food and Drug Administration (2001) tolerance level during ice storage. It seems that the levels of histamine could be a suitable freshness indicator of rainbow trout during ice storage. 相似文献
83.
Amir Ali Hamidieh Davood Beiki Pedram Paragomi Babak Fallahi Maryam Behfar Armaghan Fard‐Esfahani Ashraf Sadat Hosseini Ahmadreza Shamshiri Mohammad Eftekhari Ardeshir Ghavamzadeh 《Pediatric transplantation》2014,18(5):510-517
MIBG is an effective component in treatment of neuroblastoma. Furthermore, MIBG scintigraphy is an imaging modality in primary assessments. None of the previous studies have evaluated the role of pretransplant MIBG scintigraphy in decision making for neuroblastoma treatment. We selected therapeutic regimen based on pretransplant 131I‐MIBG scintigraphy. Twenty high‐risk patients were enrolled. On day ?30, patients underwent diagnostic MIBG scintigraphy. Patients were then subdivided into two groups (10 cases in each arm). MIBG‐avid subgroup received MIBG (12 mCi/kg), etoposide (1200 mg/m2), carboplatin (1500 mg/m2), and melphalan (210 mg/m2). Non‐MIBG‐avid subgroup received etoposide (600 mg/m2), carboplatin (1200 mg/m2), and melphalan (150 mg/m2). Patients received CRA after ASCT. Mean age at diagnosis was 42.5 months (range, 17–65) in MIBG‐avid and 38.9 months (range, 18–65) in non‐MIBG‐avid patients. Mean age at diagnosis and transplantation did not reveal significant difference between two subgroups. In MIBG‐avid patients, the three‐yr OS was 66 ± 21%. In MIBG‐non‐avid subgroup, the three‐yr OS was 53 ± 20%. In MIBG‐avid and non‐MIBG‐avid subgroups, the three‐yr EFS were 66 ± 21% and 47 ± 19%, respectively. These findings may suggest an effective role in selecting the therapeutic strategy for pre‐ASCT MIBG scintigraphy in high‐risk neuroblastoma. MIBG‐avid subset may benefit from the combination of therapeutic MIBG and high dose of chemotherapy. 相似文献
84.
Hamid Kharatzadeh Mousa Alavi Abolfazl Mohammadi Denis Visentin Michelle Cleary 《Nursing & health sciences》2020,22(2):445-453
Professional quality of life is related to psychological well‐being for nurses with implications for quality patient care. This study evaluated the effectiveness of emotional regulation training on depression, anxiety and stress, and professional quality of life for intensive and critical care nurses. In this experimental comparison trial, 60 intensive and critical care nurses were randomly assigned to treatment and wait‐list control groups. The treatment group received six sessions of emotional regulation training, while the wait‐list control group received no treatment. Outcome measures were: the Cognitive Emotion Regulation Questionnaire; the Depression, Anxiety and Stress Scale; and the Professional Quality of Life Scale in a pre‐post design. The treatment group demonstrated greater improvements in burnout and compassion satisfaction compared with the wait‐list control group. No significant reduction in compassion fatigue was found compared with controls. Some cognitive coping strategies improved in the treatment group compared with controls, with greater reductions in depression, anxiety, and stress. This study indicates the benefits of implementing emotional regulation training programs to improve psychological well‐being and professional quality of life for intensive and critical care nurses. 相似文献
85.
Dihydronaphthofurans (DHNs) are an important class of arene ring-fused furans which are widely found in many natural and non-natural products and drug candidates with relevant biological and pharmacological activities. Furthermore, vinylidene-naphthofurans exhibit photochromic properties when exposed to UV or sun light at room temperature. For these reasons, a vast array of synthetic procedures for the preparation of dihydronaphthofurans including annulation of naphthols with various reagents, cycloaddition reactions ([3 + 2], [4 + 1] and Diels–Alder), intramolecular transannulation, Friedel–Crafts, Wittig, Claisen rearrangement, neophyl rearrangement and other reactions under various conditions have been developed over the past decades. This review aims to describe the different strategies developed so far for the synthesis of dihydronaphthofurans and their applications. After a brief introduction to the types of dihydronaphthofurans and their biological activities, the different synthetic approaches such as chemical, photochemical, and electrochemical, methods are described and organized on the basis of the catalysts and the other reagents employed in the syntheses. The subsequent section focuses on biological and pharmacological applications and photochromic properties of the target compounds.Dihydronaphthofurans (DHNs) are an important class of arene ring-fused furans which are widely found in many natural and non-natural products and drug candidates with relevant biological and pharmacological activities. 相似文献
86.
Abolfazl Mohammadbeigi Shahram Arsang-Jang Ehsan Sharifipour Alireza Koohpaei Mostafa Vahedian Narges Mohammadsalehi Masoud Jafaresmaeili Moharam Karami Siamak Mohebi 《急性病杂志》2021,10(4):150-154,后插1
Objective: To identify the incidence rate, relative risk, hotspot regions and incidence trend of COVID-19 in Qom province, northwest part of Iran in the first s... 相似文献
87.
P W Radke J vom Dahl R Hoffmann H G Klues M Hosseini U Janssens P Hanrath 《Catheterization and cardiovascular interventions》2001,53(3):334-340
Restenosis remains the major limitation of coronary stent implantation, especially in diffuse forms of in-stent restenosis. In this study, rotablation (RA) with adjunct angioplasty of in-stent restenosis was performed in 84 patients. Clinical follow-up and control angiography were obtained 6-month postprocedure. The rate of recurrent restenosis after rotablation for in-stent restenosis at 6-month angiographic follow-up was 45%, resulting in a rate of major adverse cardiac events of 35%. At 3-year follow-up, the cumulative event-free survival rate was 57% for the entire population. The only predictor of MACE at 3-year clinical follow-up by multivariate logistic regression analysis was in-stent lesion length. RA for the treatment of diffuse in-stent restenosis is thereby characterized by high procedural success rates and recurrent angiographic restenosis in 45% of patients with diffuse lesions. Major adverse cardiac events occur most likely within the first 6 months postprocedure. Three years after rotablation of in-stent restenosis, 43% of patients had experienced at least one major adverse cardiac event. Cathet Cardiovasc Intervent 2001;53:334-340. 相似文献
88.
The impact of vitamin and/or mineral supplementation on lipid profiles in type 2 diabetes 总被引:3,自引:0,他引:3
Farvid MS Siassi F Jalali M Hosseini M Saadat N 《Diabetes research and clinical practice》2004,65(1):21-28
OBJECTIVE: The purpose of the present study was to assess the impact of Mg + Zn, Vitamins C + E, and combination of these micronutrients on serum lipid and lipoprotein profiles in type 2 diabetic patients. MATERIALS AND METHODS: In a randomized, double-blind, placebo controlled clinical trial, 69 type 2 diabetic patients were randomly divided into four groups, each group receiving one of the following daily supplement for 3 months; group M: 200 mg Mg and 30 mg Zn (n = 16), group V: 200mg Vitamin C and 150 mg Vitamin E (n = 18), group MV: minerals plus vitamins (n = 17), group P: placebo (n = 18). Fasting blood and urine samples were collected at the beginning and at the end of the trial. Serum triglyceride, total cholesterol, high density lipoprotein cholesterol (HDL-c) and low density lipoprotein cholesterol (LDL-c) were measured enzymatically. Apolipoproteins (apo) A1 and B were measured by immunoturbidimetric method. Adjustment for differences in baselines covariates and changes in variables during study were performed by analysis of covariance using general linear models. RESULTS: Results indicate that after 3 months of supplementation mean serum levels of HDL-c and apo A1 increased significantly in the MV group by 24% (50.4 +/-19.3 mg/dl versus 40.6 +/- 10.8 mg/dl) and 8.8% (169.8 +/- 33.8 mg/dl versus 156.1+ /- 23.9 mg/dl), respectively (P < 0.01). There were no significant changes in the levels of these parameters in the other three groups. Serum levels of total cholesterol, LDL-c, triglyceride, and apo B were not altered after supplementation in all four groups. CONCLUSION: It is concluded that since co-supplementation of Mg, Zn, Vitamins C and E significantly increases HDL-c and apo A1, supplementation of these micronutrients could be recommended for the type 2 diabetic patients based on their daily requirements. 相似文献
89.
Reza Pakzad Pooneh Malekifar Zainab Shateri Milad Zandi Sara Akhavan Rezayat Maral Soleymani Mohammad Reza Karimi Seyed Esmaeil Ahmadi Ramin Shahbahrami Iraj Pakzad Fatemeh Abdi Abbas Farahani Saber Soltani Mina Mobini Kesheh Parastoo Hosseini 《Journal of clinical laboratory analysis》2022,36(1)
BackgroundTo provide information about pathogens’ coinfection prevalence with SARS‐CoV‐2 could be a real help to save patients’ lives. This study aims to evaluate the pathogens’ coinfection prevalence among COVID‐19 patients.MethodIn order to find all of the relevant articles, we used systematic search approach. Research‐based databases including PubMed, Web of Science, Embase, and Scopus, without language restrictions, were searched to identify the relevant bacterial, fungal, and viral coinfections among COVID‐19 cases from December 1, 2019, to August 23, 2021. In order to dig deeper, other scientific repositories such as Medrxiv were probed.ResultsA total of 13,023 studies were found through systematic search. After thorough analysis, only 64 studies with 61,547 patients were included in the study. The most common causative agents of coinfection among COVID‐19 patients were bacteria (pooled prevalence: 20.97%; 95% CI: 15.95–26.46; I 2: 99.9%) and less frequent were virus coinfections (pooled prevalence: 12.58%; 95% CI: 7.31–18.96; I 2: 98.7%). The pooled prevalence of fungal coinfections was also 12.60% (95% CI: 7.84–17.36; I 2: 98.3%). Meta‐regression analysis showed that the age sample size and WHO geographic region did not influenced heterogeneity.ConclusionWe identified a high prevalence of pathogenic microorganism coinfection among COVID‐19 patients. Because of this rate of coinfection empirical use of antibacterial, antifungal, and antiviral treatment are advisable specifically at the early stage of COVID‐19 infection. We also suggest running simultaneously diagnostic tests to identify other microbiological agents’ coinfection with SARS‐CoV‐2. 相似文献
90.
Soheil Zamani Anbardan Javad Mokhtari Ahmad Yari Abolfazl Hassani Bozcheloei 《RSC advances》2021,11(34):20788
Oxidative dehydrogenative homo-coupling of amines to imines and cross-coupling of amines with alcohols to amides was achieved with high to moderate yields at room temperature in THF using Cu-MOF as an efficient and recyclable heterogeneous catalyst under mild conditions. Different primary benzyl amines and alcohols could be utilized for the synthesis of a wide variety of amides and imines. The Cu-MOF catalyst could be recycled and reused four times without loss of catalytic activity.Oxidative dehydrogenative homo or cross-coupling of amines with alcohols to imines and amides was achieved with high to moderate yields at room temperature using Cu-MOF as an efficient and recyclable heterogeneous catalyst. 相似文献