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排序方式: 共有3347条查询结果,搜索用时 31 毫秒
161.
目的探讨吸烟量对高血压患者血总胆固醇(TC)、总甘油三酯(TG)、高密度脂蛋白胆固醇(HDL-C)、低密度脂蛋白胆固醇(LDL-C)的影响,为冠心病的防治提供依据。方法采用流行病学问卷调查表的形式,没有吸烟史的高血压患者99例和有吸烟史的高血压患者105例,并按吸烟史的情况进行调查,按吸烟量分为吸烟0、1、2、3级。对比分析4个等级组四项血脂水平。结果吸烟1、2、3级TC、TG、LDL水平显著高于吸烟0级(P<0.01),吸烟3级HDL显著低于吸烟0级(P<0.01)。结论吸烟与高脂血症有密切关系,是高血压病的危险因素之一,吸烟可影响高血压病的防治。 相似文献
162.
Raviduth Ramful Thefye P. M. Sunthar Elia Marin Wenliang Zhu Giuseppe Pezzotti 《Materials》2022,15(4)
Treatment modification to improve the durability of bamboo against biotic and abiotic factors often results in adverse effects to its mechanical properties due to changes in hygroscopic characteristics. This study aims at exploring in more detail, the effect of treatment modification, in particular smoke treatment, on the hygroscopic nature of bamboo. In the first part of this study, changes to its chemical structure were investigated by Raman and Fourier-transform infrared (FTIR) spectroscopic techniques. From Raman analysis, specific bands attributed to lignin component in bamboo, namely at 1600 cm−1 and 1632 cm−1, which varied in intensities among treated and untreated specimens, could be considered to assess the extent of treatment modification. Besides, FTIR results showed that the chemical constituents of bamboo inner and outermost surfaces vary extensively with distinctive changes during treatment modification. The steam component in smoke treatment is assumed to cause a slight increase in the moisture content in the outermost surface of smoked bamboo as evidenced by FTIR results. In addition, the hydrophobic surface of smoked bamboo, which was affected during smoke treatment modification due to superior mean roughness parameter in its outermost surface, impacted its water-repelling ability. From FTIR results, an increase in lignin in bamboo was confirmed at peak 1114 cm−1, which occurred as a result of thermal effect above a temperature of 100 °C leading to poly-condensation reactions. The increase in lignin is assumed to cause an overall increase in hardness of smoked bamboo which was found to be two-fold higher when compared with the untreated ones. The approach of this research investigation, which has shown the benefit of using spectroscopic techniques to monitor and understand the changes in the hygroscopic nature of bamboo surfaces, can likewise be considered to predict the corresponding effects of treatment modification or degradation on the mechanical properties of natural materials. 相似文献
163.
目的:以人红细胞为模型,评估香烟烟雾提取物(CSE)对生物膜的损害作用.方法:以市售香烟提取CSE,然后作用于红细胞,通过测定细胞溶血率、膜脂质过氧化水平、细胞内高铁血红蛋白以及还原谷胱甘肽含量、膜磷脂组成和膜蛋白谱变化等指标,对CSE导致的红细胞膜损害进行评估.结果:香烟烟雾水溶物CSE可导致红细胞溶血,红细胞丙二醛和高铁血红蛋白水平升高,谷胱甘肽含量降低.并且能够改变膜磷脂组成和诱导膜蛋白聚集.结论:香烟烟雾水溶物对红细胞具有氧化损害作用,这种损害作用可进一步导致红细胞丧失其正常生理功能. 相似文献
164.
Makhloufi Zoulikha Qingqing Xiao George Frimpong Boafo Marwa A.Sallam Zhongjian Chen Wei He 《药学学报(英文版)》2022,12(2):600-620
The use of small interfering RNAs (siRNAs) has been under investigation for the treatment of several unmet medical needs, including acute lung injury/acute respiratory distress syndrome (ALI/ARDS) wherein siRNA may be implemented to modify the expression of pro-inflammatory cytokines and chemokines at the mRNA level. The properties such as clear anatomy, accessibility, and relatively low enzyme activity make the lung a good target for local siRNA therapy. However, the translation of siRNA is restricted by the inefficient delivery of siRNA therapeutics to the target cells due to the properties of naked siRNA. Thus, this review will focus on the various delivery systems that can be used and the different barriers that need to be surmounted for the development of stable inhalable siRNA formulations for human use before siRNA therapeutics for ALI/ARDS become available in the clinic. 相似文献
165.
Although numerous studies have linked smoking with lower extremity wound and bone healing complications, a comprehensive study on the effects of smoking in foot and ankle surgery has not yet been reported. The purpose of the present study was to report the results of our systemic literature review, identifying the effects of tobacco use on common foot and ankle procedures. The systematic literature review was performed according to guidelines set by the PRIMSA statement (Preferred Reporting Items for Systematic Review and Meta-Analyses). Smoking, as a single risk factor, was analyzed and used to compare adverse outcomes in the postoperative setting of foot and ankle surgery. We reviewed 528 abstracts that met our initial identification criteria. After an extensive review process, 46 of the articles (8.71%) met the eligibility requirements to be included in the present study. Distal bunionectomy with osteotomy, first metatarsophalangeal joint arthrodesis, Lapidus bunionectomy, toe amputation, transmetatarsal amputation, Syme's amputation, open reduction internal fixation (ORIF) of calcaneal fractures, ankle fracture ORIF, pilon fracture ORIF, subtalar arthrodesis, rearfoot arthrodesis, tibiocalcaneal arthrodesis, ankle arthrodesis, total ankle arthroplasty, and plastic surgery procedures and their respective negative association with smoking was identified and described in our review. Our systematic literature review revealed that procedures involving arthrodesis, fracture ORIF, and plastic surgery were associated with negative outcomes in smokers. Procedures that did not involve osseous unions such as total ankle arthroplasty and amputations did not appear to have negative outcomes associated with smoking. 相似文献
166.
香烟烟雾可吸入微粒对大鼠支气管肺组织的氧化损伤研究 总被引:2,自引:1,他引:1
目的探讨香烟烟雾可吸入微粒对支气管肺组织的氧化损伤作用。方法采集并分析香烟可吸入微粒后,染毒大鼠,观察肺组织病理形态的变化,测定肺泡灌洗液中白细胞总数和分类计数及肺匀浆中丙二醛(MDA)含量、超氧化物歧化酶(SOD)和谷胱甘肽过氧化物酶(GSH-Px)活性。结果香烟组的病理改变以炎症为主,各观察指标与对照组比较有差异。结论香烟烟雾可吸入微粒对大鼠气道及肺组织的刺激引发炎性反应,而活性氧介导的炎症反应是其致炎作用机制之一。 相似文献
167.
Leah C. Stevenson India Bohanna Jan A. Robertson Alan R. Clough 《Drug and alcohol review》2013,32(6):627-630
168.
《The journal of maternal-fetal & neonatal medicine》2013,26(8):1222-1227
Objective: Assess the relative effects of a variety of illicit and licit drugs on risk for adverse birth outcomes. Methods: We used data from two large prospective investigations, and a novel analytic method, recursive partitioning class analysis to identify risk factors associated with preterm birth and delivering a small for gestational age infant. Results: Compared to cocaine and opiate non-users, cocaine users were 3.53 times as likely (95% CI: 1.65-7.56; p = 0.001) and opiate users 2.86 times as likely (95% CI: 1.11-7.36; p = 0.03) to deliver preterm. The odds of delivering a small for gestational age infant for women who smoked more than two cigarettes daily was 3.74, (95% CI: 2.47-5.65; p<0.0001) compared to women who smoked two or less cigarettes daily and had one previous child. Similarly, less educated, nulliparous women who smoked two or fewer cigarettes daily were 4.12 times as likely (95% CI: 2.04-8.34; p < 0.0001) to have a small for gestational age infant. Conclusions: Among our covariates, prenatal cocaine and opiate use are the predominant risk factors for preterm birth; while tobacco use was the primary risk factor predicting small for gestational age at delivery. Multi-substance use did not substantially increase risk of adverse birth outcomes over these risk factors. 相似文献
169.
In this study 10 commercial top selling cigarette brands in Spain have been machine smoked and the mainstream smoke has been analyzed. Multifunctional analysis has been satisfactorily employed to correlate the effect of the main design features of the cigarettes including amount of tobacco, filter size or paper weight with the amount of smoked tobacco and with the ratio CO2/CO. The composition of the vapor phase and that of the particulate matter have been analyzed. The particulate matter retained in the filter of the cigarettes has also been analyzed showing a distinct behavior of the compounds condensed in the cigarette filters and in the traps, related to their retention time. A general trend for the relative yield of some compounds in the different brands have been identified and confirmed by multifunctional analysis. Nevertheless, there are some noticeable compounds that behave differently in the different brands. 相似文献
170.
Omar F. Khabour Enas S. Alsatari Mohammad Azab Karem H. Alzoubi May F. Sadiq 《Environmental and molecular mutagenesis》2011,52(3):224-228
Tobacco smoking is a major world health problem. Recently, waterpipe smoking has become more popular in many countries. Although the genotoxicity associated with cigarette smoking has been extensively investigated, studies evaluating such toxicity in waterpipe users are still lacking. In this study, we examined the genotoxicity of waterpipe smoking in lymphocytes compared with the genotoxicity of cigarette smoking. Genotoxicity was evaluated using the sister chromatid exchanges (SCEs) assay. Fifty waterpipe smokers and 18 healthy nonsmokers participated in this study. Additionally, 18 heavy cigarette smokers (CS) were recruited for comparison. The results show that waterpipe smoking and cigarette smoking significantly increase the frequencies of SCEs (P < 0.01) compared with those of nonsmokers, indicating the genotoxic effect of tobacco smoking. In addition, frequencies of SCEs were significantly higher among waterpipe smokers compared with CS (P < 0.01), indicating that waterpipe smoking is more genotoxic than cigarette smoking. Moreover, the frequency of SCEs increased with the extent of waterpipe use. In conclusion, waterpipe smoking is genotoxic to lymphocytes and the magnitude of its genotoxicity is higher than that induced by regular cigarette smoking. Environ. Mol. Mutagen., 2011. © 2010 Wiley‐Liss, Inc. 相似文献