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排序方式: 共有8810条查询结果,搜索用时 18 毫秒
151.
152.
红心大白菊挥发油成分的GC-MS分析 总被引:2,自引:4,他引:2
目的 :分析我国中药材GAP基地红心大白菊挥发油的化学成分 ,为其质量评价提供科学依据。方法 :采用水蒸气蒸馏法提取红心大白菊挥发油 ,用GC毛细管柱进行分析 ,归一化法测定其相对含量 ,并用GC-MS法鉴定化学成分。结果 :检出 136个色谱峰 ,鉴定出 47个化合物 ,占挥发油总量的 62.24%。结论 :红心大白菊挥发油中 ,雪松醇、喇叭醇和 1-(1,5-二甲基-4-己烯基 )-4-甲基苯是其主要成分 ,以倍半萜类化合物喇叭醇含量最高 ,占总挥发油量的 13.9%。 相似文献
153.
年龄相关性黄斑变性(ARMD)是引起中老年人视力丧失的首要原因,其确切病因尚未明了,故治疗效果不佳。脂褐素随着年龄增长在视网膜色素上皮的积累是眼睛老化的标志,通过光化学作用等影响正常视网膜色素上皮细胞的功能,与ARMD的发生发展有一定联系。本文就脂褐素及其与ARMD的关系进行综述。 相似文献
154.
Abrupt visual loss during anti-vascular endothelial growth factor treatment for type 3 neovascularization
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AIM: To investigate the incidence of abrupt visual loss and its associated factors, during anti-vascular endothelial growth factor (VEGF) treatment for type 3 neovascularization.
METHODS: This retrospective study included 137 eyes that were newly diagnosed with type 3 neovascularization. All eyes were treated with anti-VEGF therapy. Abrupt visual loss was defined as loss of 5 or more lines in best-corrected visual acuity (BCVA) in comparison to the previous visit. The incidence and timing of abrupt visual loss as well as the factors associated with it, were determined. In addition, the BCVA at the final follow-up was compared between the eyes with and those without abrupt visual loss.
RESULTS: The mean follow-up period was 42.4±18.9mo after diagnosis, and abrupt visual loss was noted in 22 eyes (16.1%) at a mean of 19.6±13.9mo. Abrupt visual loss was found to be associated with subretinal hemorrhage in 11 eyes (50.0%), development of or increase in the height of pigment epithelial detachment with fluid in 8 eyes (36.4%), and tears in the retinal pigment epithelium in 3 eyes (13.6%). The logarithm of minimum angle of resolution (logMAR) mean BCVA at the final follow-up was 2.07±0.67 (Snellen equivalents: 20/2349) and 1.00±0.55 (20/200) in eyes with and without abrupt visual loss, respectively. BCVA was significantly worse in the eyes with abrupt visual loss (P<0.001).
CONCLUSION: Abrupt visual loss is noted in 16.1% of patients with type 3 neovascularization and is associated with poor visual outcome. Additional studies are needed to determine how abrupt visual loss can be prevented. 相似文献
155.
Kwanhoon Choi Jeongyeon Yoon Hyun Kyo Lim Sungwoo Ryoo 《The Korean journal of physiology & pharmacology》2014,18(2):95-101
Cardiovascular disease is the prime cause of morbidity and mortality and the population ages that may contribute to increase in the occurrence of cardiovascular disease. Arginase upregulation is associated with impaired endothelial function in aged vascular system and thus may contribute to cardiovascular disease. According to recent research, Korean Red Ginseng water extract (KRGE) may reduce cardiovascular disease risk by improving vascular system health. The purpose of this study was to examine mechanisms contributing to age-related vascular endothelial dysfunction and to determine whether KRGE improves these functions in aged mice. Young (10±3 weeks) and aged (55±5 weeks) male mice (C57BL/6J) were orally administered 0, 10, or 20 mg/mouse/day of KRGE for 4 weeks. Animals were sacrificed and the aortas were removed. Endothelial arginase activity, nitric oxide (NO) generation and reactive oxygen species (ROS) production, endothelial nitric oxide synthase (eNOS) coupling, vascular tension, and plasma peroxynitrite production were measured. KRGE attenuated arginase activity, restored nitric oxide (NO) generation, reduced ROS production, and enhanced eNOS coupling in aged mice. KRGE also improved vascular tension in aged vessels, as indicated by increased acetylcholine-induced vasorelaxation and improved phenylephrine-stimulated vasoconstriction. Furthermore, KRGE prevented plasma peroxynitrite formation in aged mice, indicating reduced lipid peroxidation. These results suggest KRGE exerts vasoprotective effects by inhibiting arginase activity and augmenting NO signaling and may be a useful treatment for age-dependent vascular diseases. 相似文献
156.
目的了解冠心病患者中斑块稳定组与不稳定组之间红细胞分布宽度(red blood cell distribution width,RDW)是否有差异,是否能成为早期识别急性冠脉综合征(acute coronary syndromes,ACS)的一个潜在标记物;同时研究血清超敏C反应蛋白(hs-CRP),并探讨二者之间是否有联系。方法 213例患者根据临床症状、相关标准及造影结果分成ACS组、SAP组及对照组,测定每位患者的RDW、hs-CRP及血脂指标。结果 (1)ACS组RDW值显著高于SAP组及对照组,而SAP组与对照组之间无显著性差异;(2)ACS组hs-CRP显著高于SAP组及对照组,而SAP组与对照组之间无显著性差异;(3)多因素Longistic回归分析发现RDW水平与ACS之间存在独立的显著性相关关系;(4)RDW与血清hs-CRP呈显著性正相关。结论 ACS组患者RDW是明显升高的,提示RDW的升高可能参与斑块不稳定的进展过程,可能是反映斑块易损性的一个潜在标记物。 相似文献
157.
Dipti Upadhye Rajat S. Das Jayanta Ray Shukdeb Acharjee Kanjaksha Ghosh Roshan B. Colah 《Hemoglobin》2018,42(1):43-46
Hemoglobinopathies are a group of inherited single gene disorders. There are reports on hemoglobin (Hb) variants identified in the tribal and non-tribal populations of Tripura State in northeastern India. This study aimed to determine the spectrum of hemoglobinopathies and enzymopathies by newborn screening in Tripura State and assess the extent of neonatal jaundice. A total of 2400?cord blood samples were collected and analyzed by high performance liquid chromatography (HPLC). Further confirmation of any abnormal HPLC was done by DNA analysis. The samples were also screened for deficiency of enzymopathies, glucose-6-phosphate dehydrogenase (G6PD) deficiency and pyruvate kinase. Of 2400?cord blood samples screened, 225 (9.3%) were Hb E (HBB: c.79G>A) heterozygotes, 80 (3.3%) were Hb E homozygotes and one carried Hb E-β-thalassemia (β-thal). Other Hb abnormalities were also detected including 15 Hb S (HBB: c.20A>T) heterozygotes, two Hb D-Punjab (HBB: c.364G>C) heterozygotes and two compound heterozygotes for Hb D-Punjab and Hb E. Of the 80 homozygous Hb E babies, four were non-tribal and 76 babies were tribal, and 225 patients carried Hb E trait, 141 were tribal, while 84 were non-tribal. Of 40 G6PD deficient babies identified, 13 had coinherited Hb E and two babies had pyruvate kinase deficiency. α Genotyping was performed in 162 affected babies, 50 of them carried α gene deletions. Newborn screening programs for Hb E, other hemoglobinopathies and G6PD deficiency must be encouraged in the malaria-endemic northeastern region of India. Drug-induced hemolysis can also be avoided by screening for G6PD deficiency at birth. 相似文献
158.
Alessandra Andrisani Gabriella Donà Chiara Sabbadin Elena Tibaldi Francesco Dessole Valentina Bosello Travain 《Gynecological endocrinology》2018,34(3):233-237
Polycystic ovary syndrome (PCOS)is a gynecological endocrine disorder which is associated with systemic inflammatory status inducing red blood cells (RBC) membrane alterations related to insulin resistance and testosterone levels which could be greatly improved by myo-inositol (MYO) uptake. In this study we aim to evaluate the effect of MYO in reducing oxidative-related alterations through in vitro study on PCOS RBC. Blood samples from two groups of volunteers, control group (CG, n?=?12) and PCOS patient group (PG, n?=?12), were analyzed for band 3 tyrosine phosphorylation (Tyr-P), high molecular weight aggregate (HMWA), IgG in RBC membranes, and glutathione (GSH) in cytosol, following O/N incubation in the presence or absence of MYO. PCOS RBC underwent oxidative stress as indicated by higher band 3 Tyr-P and HMWA and increased membrane bound autologous IgG. Twenty four hours (but not shorter time) MYO incubation, significantly improved both Tyr-P level and HMWA formation and concomitant membrane IgG binding. However, no relevant modification of GSH content was detected. PCOS RBC membranes are characterized by increased oxidized level and enhanced sensitivity to oxidative injuries leading to potential premature RBC removal. MYO treatment is effective in reducing oxidative related abnormalities in PCOS patients probably restoring the inositol phospholipid pools of the membranes. 相似文献
159.
《Current medical research and opinion》2013,29(8):608-613
SummaryRecent investigations have revealed that erythrocytes from patients with chronic arterial occlusive disease are significantly less deformable than red blood cells from healthy subjects. The influence of pentoxifylline on red blood cell fluidity was measured by a standard filtration technique using 8 μm membrane filters. Impaired deformability of erythrocytes was significantly improved in patients suffering from peripheral vascular disorders following intravenous injection of 200?mg pentoxifylline. Studies on reduced red cell deformability induced by hyperosmolarity in vitro showed that pentoxifylline (4 and 20 μg/ml) produced a dose-dependent improvement both in blood from healthy subjects and from patients with peripheral arterial occlusive disease. The results suggest that the positive therapeutic effect of pentoxifylline in peripheral arterial occlusive disease is mediated by improving red cell fluidity in the microcirculation. 相似文献
160.