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排序方式: 共有810条查询结果,搜索用时 15 毫秒
31.
Hesham R. El-Seedi Rehan M. El-Shabasy Shaden A. M. Khalifa Aamer Saeed Afzal Shah Raza Shah Faiza Jan Iftikhar Mohamed M. Abdel-Daim Abdelfatteh Omri Nahid H. Hajrahand Jamal S. M. Sabir Xiaobo Zou Mohammed F. Halabi Wessam Sarhan Weisheng Guo 《RSC advances》2019,9(42):24539
Nanoparticles (NPs) are new inspiring clinical targets that have emerged from persistent efforts with unique properties and diverse applications. However, the main methods currently utilized in their production are not environmentally friendly. With the aim of promoting a green approach for the synthesis of NPs, this review describes eco-friendly methods for the preparation of biogenic NPs and the known mechanisms for their biosynthesis. Natural plant extracts contain many different secondary metabolites and biomolecules, including flavonoids, alkaloids, terpenoids, phenolic compounds and enzymes. Secondary metabolites can enable the reduction of metal ions to NPs in eco-friendly one-step synthetic processes. Moreover, the green synthesis of NPs using plant extracts often obviates the need for stabilizing and capping agents and yields biologically active shape- and size-dependent products. Herein, we review the formation of metallic NPs induced by natural extracts and list the plant extracts used in the synthesis of NPs. In addition, the use of bacterial and fungal extracts in the synthesis of NPs is highlighted, and the parameters that influence the rate of particle production, size, and morphology are discussed. Finally, the importance and uniqueness of NP-based products are illustrated, and their commercial applications in various fields are briefly featured.Nanoparticles (NPs) are new inspiring clinical targets that have emerged from persistent efforts with unique properties and diverse applications. 相似文献
32.
Aamer Saeed Fayaz Ali Larik Pervaiz Ali Channar Haroon Mehfooz Mohammad Haseeb Ashraf Qamar Abbas Mubashir Hassan Sung‐Yum Seo 《Chemical biology & drug design》2017,90(5):764-777
In this study, some new azomethine‐triazole hybrids 5a–5l derived from N‐benzoyl‐L‐phenylalanine were synthesized and characterized. The synthesized compounds showed first‐rate, urease inhibition, and compounds 5c and 5e were found to be most effective inhibitors with 0.0137 ± 0.00082 μm and 0.0183 ± 0.00068 μm , respectively (thiourea 15.151 ± 1.27 μm ). The kinetic mechanism of urease inhibition revealed the compounds 5c and 5e to be non‐competitive inhibitors, whereas compounds 5d and 5j were found to be of mixed‐type inhibitors. Docking studies also indicated better interaction patterns with urease enzyme. The results of enzyme inhibition, kinetic mechanism and molecular docking suggest that these compounds can serve as lead compounds in the design of more effective urease inhibitors. 相似文献
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Prednisone does not prevent recurrent fetal death in women with antiphospholipid antibody 总被引:10,自引:0,他引:10
Effects of therapy, antibody titer, and pregnancy history on pregnancy outcome were evaluated in pregnancies of women with antiphospholipid antibody. Prior fetal death and a high antiphospholipid antibody titer (greater than 40 IgG phospholipid units) contributed independently, in an additive manner, to current fetal loss. Twenty-one pregnancies occurred in asymptomatic women who had both prior fetal death and a high IgG antiphospholipid antibody titer. In this very high-risk group, 9 of 11 (82%) of pregnancies treated with prednisone, 10 to 60 mg/day, ended in fetal death, compared with 5 of 10 (50%) not treated with prednisone (p approximately 0.01, life-table analysis). Of pregnancies treated with aspirin, 80 mg/day, 9 of 14 (64%) treated and 5 of 7 (71%) not treated with prednisone had a fetal death (difference not significant). Prednisone does not improve, and may worsen, current fetal outcome in asymptomatic pregnant women with a high antiphospholipid antibody titer and prior fetal death. 相似文献
36.
I Moncica P I Oh I ul Qamar D Scolnik G S Arbus D Hebert J W Balfe G Koren 《Archives of disease in childhood》1995,73(2):154-156
In a crossover design, control of blood pressure by extended release felodipine was compared with control by prolonged action nifedipine in 21 children with renal hypertension. Compliance with once daily felodipine was higher than with nifedipine, at 95.6 (SEM 2.7)% v 78.9 (6.0)% (p = 0.02). Mean diastolic blood pressure was lower during the day with felodipine than with nifedipine, at 77.6 (2.4) v 84.4 (2.8) mm Hg (p = 0.05). Similarly, blood pressure load (the percentage of the day during which the child had blood pressure exceeding the upper limits of normal for age) was lower for felodipine than for nifedipine: 43.5 (5.5)% v 61.3 (6.3)%. There was an opposite trend during the night, though this did not reach statistical significance. These data suggest that once a day felodipine is effective in children with hypertension. This may be because of improved compliance. 相似文献
37.
V. K. Rehan S. M. Menticoglou M. M. Seshia J. M. Bowman 《Archives of disease in childhood. Fetal and neonatal edition》1995,73(1):F41-F43
A case of fetofetal transfusion syndrome (FFTS) in a monochorionic triplet pregnancy, in which all three fetuses shared a common circulation, is reported. All babies were born alive, although two died within two days of delivery. This case highlights the problem of FFTS with accompanying high perinatal morbidity and mortality in naturally occurring monochorionic triplet gestations. 相似文献
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We examined (1) the observer variability (both interobserver and intraobserver) in interpretation of abdominal radiographs of infants with suspected necrotizing enterocolitis (NEC), (2) the interobserver variability for individual radiologic signs used to diagnose NEC, and (3) the influence of experience in determining the extent of observer variability. Our hypotheses were (1) there would be considerable observer variability in interpretation of abdominal radiographs of infants with suspected NEC; (2) the extent of observer variability would differ for individual radiologic signs of NEC; and (3) the extent of observer variability would be determined by the observer's experience. The participants included 12 observers: two pediatric radiologists, four attending neonatologists, three neonatal fellows, and three pediatric residents. The participating observers under similar interpretation conditions, twice independently, interpreted the same 40 pairs of abdominal radiographs from infants with suspected NEC. The interval between the two interpretations was 3 to 6 months. Intraobserver and interobserver variability was assessed by applying the Kappa statistic to the radiologic signs of NEC for the two separate interpretations. The observers were blinded to patient's identity and the clinical course. Each observer recorded the absence, suspicion, or presence of (1) intestinal distention, (2) air fluid levels, (3) bowel wall thickening, (4) pneumatosis intestinalis, (5) portal venous gas, (6) pneumoperitoneum, and (7) NEC. We found low intraobserver and interobserver agreements. There was considerable variation in observer variability for individual radiologic signs. Trained observers performed better than intraining observers. We conclude that the radiologic signs in isolation should not be considered reliable. We recommend studies to formulate more objective criteria for many of the radiographic features of NEC. Standardization and periodic enforcement of these criteria among observers could reduce observer variability. We suggest that, to decrease both false-negative and false-positive interpretation, an experienced observer should always review the radiographs of infants with suspected NEC. 相似文献
40.
Aslam AF Aslam AK Qamar MU Levey R 《Journal of the National Medical Association》2005,97(7):1031-1035
Primary lymphedema tarda is considered to be a congenital disease with delayed manifestations. We report a case of isolated lymphedema of the left upper extremity in an 88-year-old African-American male. The diagnosis of lymphedema was confirmed by lymphoscintigraphy, and appropriate diagnostic studies were done to rule out other known causes of lymphedema. Lymphoscintigraphic findings were consistent with idiopathic primary lymphedema. During the course of investigations, the patient was found to have adenocarcinoma in situ of the sigmoid colon with no evidence of metastatic spread. Based on the available data, we were unable to establish a causative relationship between colonic carcinoma and lymphedema in our patient. Therefore, this case can best be described as a case of Idiopathic primary lymphedema tarda. We emphasize the use of histopathologic examination in the diagnostic algorithm to rule out underlying malignant process only in patients with radionuclide findings suggestive of secondary lymphedema with no obvious etiology. 相似文献