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排序方式: 共有6009条查询结果,搜索用时 15 毫秒
91.
《Pharmaceutical biology》2013,51(3):304-309
Context: Clerodendrum infortunatum Linn. is a widely used plant in the Indian indigenous system of medicine for the treatment of tumors.Objective: The present study evaluated the anticancer activity of methanol extract of C. infortunatum (MECI) against Ehrlich’s ascites carcinoma (EAC) bearing Swiss albino mice and isolation of bioactive terpenoids from it.Methods: HPLC analysis of the methanol extract showed the presence of three major components. Out of those, two compounds were isolated and characterized as oleanolic acid and clerodinin A. The anticancer activity of MECI was assessed by measuring the tumor growth response, percentage increase of life span, study of hematological parameters, lipid peroxidation, antioxidant enzyme activity like glutathion and CAT. In vitro cytotoxicity assay was also performed using EAC cell lines.Result and conclusion: Treatment with MECI causes significant decrease in the tumor cell volume and increase in the life span. The median survival time (MST) of EAC control group was found as 19.42?±?0.91 d, whereas the MST was increased to 23.44?±?2.69 d and 27.57?±?2.57 d for the groups treated with MECI at 100 and 200?mg/kg, respectively. All the hematological parameters, malonaldehyde content and antioxidant enzymes’ activity were restored towards the normal level. IC50 value of MECI was found as 498.33 µg/mL in cytotoxicity study. The experimental results suggested that MECI has significant anticancer activity, which can be attributed to the presence of oleanolic acid and clerodinin A. 相似文献
92.
《Gait & posture》2021
BackgroundAttempts to improve protocol standards of marker-based clinical gait analysis (CGA) have been one of the main focuses of research to enhance robustness and reliability outcomes since the 1990s. Determining joint centres and axes constitutes an important aspect of those protocols. Although the hip joint is more prominent in such studies, knee joint center (KJC) and axis (KJA) directly affect all outcomes.Research questionWhat recommendations arise from the study of the scientific literature for determining knee joint parameters (KJP) for protocols of CGA?MethodsA systematic, electronic search was conducted on November 2018 using three databases with the keyword combination (“functional approach” OR “functional method” OR “functional calibration”) AND (“hip joint” OR “knee joint” OR “ankle joint”) and analyzed by four reviewers. Given the existence of a recent review about the hip joint and the lack of material about the ankle joint, only papers about the knee joint were kept. The references cited in the selected papers were also screened in the final round of the search for these publications.The quality of the selected papers was assessed and aspects regarding accuracy, repeatability, and feasibility were thoroughly considered to allow for a comparison between studies. Technical aspects, such as marker set choice, KJP determination techniques, demographics, and functional movements, were also included.ResultsThirty-one papers were included and on average received a rating of about 75 % according to the quality scale used. The results showed that functional methods are superior or equivalent to predictive methods to estimate the KJA, while a regression method was slightly better for KJC prediction.SignificanceCalibration methods should be applied to CGA whenever feasibility is reached. No study to date has focused on evaluating the in vivo RoM required to obtain reliable and repeatable results and future work should aim in this direction. 相似文献
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F. Dutheil F. Guillemin J. Biau N. Pham-Dang N. Saroul P. Clavère M. Lapeyre 《Cancer radiothérapie》2021,25(5):484-493
The identification of the different risk factors for mandibular osteoradionecrosis (ORN) must be done before and after the management of patients with head and neck cancer. Various clinical criteria for this severe radiation-induced complication are related to the patient (intrinsic radiosensitivity, malnutrition associated with thin weight loss, active smoking intoxication, microcapillary involvement, precarious oral status, hyposalivation) and/or related to the disease (oral cavity, large tumor size, tumor mandibular invasion). Therapeutic risk factors are also associated with a higher risk of ORN (primary tumor surgery, concomitant radio-chemotherapy, post-irradiation dental avulsion, preventive non-observance with the absence of stomatological follow-up and daily installation of gutters fluoride and, non-observance curative healing treatments). Finally, various dosimetric studies have specified the parameters in order to target the dose values distributed in the mandible, which increases the risk of ORN. An mean mandibular dose greater than 48–54 Gy and high percentages of mandibular volume receiving 40 to 60 Gy appear to be discriminating in the risk of developing an ORN. 相似文献
95.
Zhuo Liu Meixin Xie Zhengjuan Lu Cunjin Zhang Huiping Chen Yun Xu 《Neurological research》2020,42(7):612-617
ABSTRACT
Background/Aims
Both of neuromyelitis optica spectrum disease (NMOSDs) and idiopathic transverse myelitis (ITM) could present as acute transverse myelitis. However, long-term immunological treatment and prognosis are different for high recurrence of NMOSDs. In this study, we summarized clinical differences between acute attack myelitis of NMOSDs and ITM, we further screened serum auto-antibodies to help understand the two distinct clinical entities. 相似文献96.
Maged M. Yassin Abed El-Raoof D. Masoud Mohammed M. Yasin 《Diabetes & Metabolic Syndrome: Clinical Research & Reviews》2019,13(3):1865-1870
ObjectiveTo assess serum vitamin D status and its relations to other biochemical parameters in type 2 diabetic patients from Gaza Strip.Materials and methodsThis case-control study included 58 type 2 diabetic patients as well as 58 non-diabetic controls. Patients and controls were matched for age and gender. Data were obtained from questionnaire interview, and biochemical analysis of blood samples.ResultsSerum vitamin D was significantly lower in diabetic patients compared to non-diabetic controls (25.9 ± 11.0 versus 34.6 ± 13.8 ng/dl, % difference = 28.8%, P < 0.001). The number of patients having vitamin D deficient, insufficient and sufficient were 6 (10.4%), 35 (60.3%) and 17 (29.3%) compared to controls of 3 (5.2%), 16 (27.6%) and 39 (67.2%), respectively (χ2 = 14.672, P < 0.001). Serum glucose, glycated hemoglobin (HbA1c), serum alanine aminotransferase (ALT), aspartate aminotransferase (AST) and triglycerides were significantly higher in patients than in controls whereas serum insulin, high density lipoprotein cholesterol (HDL-C) and calcium were significantly lower in patients. Serum vitamin D showed significant negative correlations with HbA1c (r = ? 0.186, P = 0.046), ALT (r = ? 192, P = 0.040) and AST (r = ? 0.188, P = 0.044) whereas significant positive correlations were found with HDL-C (r = 0.188, P = 0.044) and calcium (r = 0.239, P = 0.010).ConclusionThe significant negative and positive correlations of vitamin D with HbA1c and calcium, respectively suggests that vitamin D supplementation would be of potential therapeutic value in clinical settings for controlling of type 2 diabetes and more importantly its complications. However, a well-designed clinical trials are needed to define the contribution of vitamin D status and therapy in the global diabetes problem. 相似文献
97.
Andreas Himmelsbach Alexandra Schneider‐Chaabane Karen Lienkamp 《Macromolecular chemistry and physics.》2019,220(24)
Asymmetrically substituted poly(diitaconate) copolymers are synthesized from 1‐((N‐tert‐butoxycarbonyl)‐2‐aminoethyl)‐4‐propyl diitaconate (PrIA) and different comonomers (N,N‐dimethyl‐acrylamide, DMAA; acrylic acid; or ((N‐tert‐butoxycarbonyl)‐2‐aminoethyl)methacrylate) by reversible addition–fragmentation chain transfer polymerization (RAFT). The RAFT copolymerization parameters of PrIA and DMAA are rDMAA = 0.49 and rPrIA = 0.17, compared to rDMAA = 0.52 and rPrIA = 0.54 obtained by free radical copolymerization (FRP). Thus, the RAFT process has a stronger trend to alternating polymerization than the FRP process. The polydispersity index of the RAFT copolymers is around 1.2–1.8, compared to 2.8–2.9 for the corresponding FRP copolymers. After removal of the tert‐butoxycarbonyl protective groups, antimicrobially active synthetic mimics of antimicrobial peptides are obtained. The thus activated poly(PrIA‐co‐DMAA) copolymers (repeat unit ratio 1:1) have an increasing activity against Escherichia coli and Staphylococcus aureus with increasing molar mass. The RAFT copolymers are slightly more active and less toxic than comparable FRP polymers, leading to a higher selectivity for bacteria over mammalian cells. Higher molar fractions of PrIA in poly(PrIA‐co‐DMAA) copolymers (up to 80 mol%) do not increase their antimicrobial activity; reduction of the BuIA content in poly(BuIA‐DMAA) (down to 10 mol%) leads to a loss of activity against both E. coli and S. aureus. 相似文献
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