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1.
据世界卫生组织统计,全球目前有烟民约13亿人,每年约有500万人死于和烟草有关的疾病,烟草已成为继高血压之后的第2号杀手。中国是世界上最大的烟草生产和消费国,中国目前的烟民数量约3.5亿,每年死于吸烟相关疾病的人数高达100万,根据流行  相似文献   

2.
烟草花叶病毒的感染和重建实验是证明核酸是遗传物质的证据链中关键的一环.主要以科学家最初发表的2篇相关研究论文为依据,对学生在学习烟草花叶病毒的感染和重建实验过程中,经常产生的如何进行烟草花叶病毒感染烟草的操作、如何将烟草花叶病毒的RNA与蛋白质相互分离、如何实现烟草花叶病毒的体外重建3个疑惑点进行探析.  相似文献   

3.
为探究过表达云南红梨bHLH转录因子对烟草抗盐性的影响,从红梨红色果皮中分离了bHLH转录因子基因PybHLH.亚细胞定位表明PybHLH蛋白定位于细胞核.以转基因PybHLH烟草和野生型烟草为材料,进行了NaCl胁迫对转基因PybHLH烟草生理生化影响研究及其相关酶基因的表达分析.表明PybHLH转基因烟草具有一定的耐盐性,一方面表现为随着盐胁迫时间延长,PybHLH转基因烟草中总可溶性糖、可溶性总蛋白和游离脯氨酸含量的增加,H2O2含量降低;另一方面表现为脯氨酸生物合成关键酶基因P5CS、抗氧化相关基因MnSOD、CuZn-SOD和POD、胁迫相关基因HSP和HSP cherpron和ABA抗盐信号途径基因NAC等均呈上调表达趋势.PybHLH的过表达提高了烟草的耐盐性,这将为进一步研究植物的耐盐机制及耐盐植物新品种的开发奠定基础.  相似文献   

4.
孝感烟草根植在荆楚大地上,孝感是楚文化的重要发祥地之一。孝感烟草组建以来,企业综合实力不断壮大。截至2010年底,全市烟草系统总资产达到8.03亿元,商品销售总额25.24亿元,实现利税5.02亿元,分别是1984年的22.65万元、2195万元、63万元的3545倍、115倍、796倍,为维护国家和消费者利益,为推进地域经济和社会又好又快发展做出了积极贡献。  相似文献   

5.
云南烟草品种资源"九五"研究进展   总被引:2,自引:0,他引:2  
1996~2000年云南省收集并鉴定评价烟草国内品种(系)60个,国外品种(系)90个,繁殖种子268份进行保存.通过多年鉴定评价筛选出优异种质K346、RG11、RG17等在云南省和全国范围内推广使用.同时,通过对烟草种子超干燥保存及其相关技术的研究,使烟草种子能够安全而长期地保存.烟草品种资源信息管理系统的建立使烟草品种资源研究工作迈向合理化、系统化、规范化的轨道.  相似文献   

6.
将葡萄蔗糖转运蛋白VvSUC27cDNA以反义方向插入到含有CaMV35s启动子的真核表达载体pBI121载体中,然后转化到烟草(Nicotianatobacumcv.Samsun)植株中.转反义VvSUC27cDNA的烟草植株在含有20g/L蔗糖的培养基上能够正常生长发育,但是通过切片观察,发现其根部发育较弱,且叶片叶绿体含量增加.可溶性糖测定发现,转基因烟草根部蔗糖含量只有野生型烟草的51%.14C蔗糖吸收实验发现转基因烟草转运外界蔗糖的能力大大降低.  相似文献   

7.
转拟南芥ICE1基因增强烟草抗寒性的研究   总被引:3,自引:0,他引:3  
ICE1是CBF冷响应通道的上游转录调控因子,通过与CBF启动子中MYC顺式作用元件的结合激活CBF3基因表达.采用RT-PCR方法,从拟南芥获得AtICE1基因,将AtICE1导入pCAMBIA1301构建35S:AtICE1植物表达载体.通过根癌农杆菌GV3101,将AtICE1基因导人烟草,T1代植株经潮霉素抗性筛选,PCR、RT-PCR检测,结果表明AtICE1基因已经整合到烟草基因组中,并在转录水平表达;在正常生长条件下,转基因烟草与对照烟草的生长未见明显区别,而在瞬时低温冻害下,转基因烟草存活率明显高于对照烟草植株,说明Atl-CEI基因可以提高低温敏感作物的耐寒性.  相似文献   

8.
为了对牡丹病程相关蛋白1(PsPRI)基因功能进行研究,构建了PsPRI基因超表达载体pBI121-PsPRI,通过农杆菌介导法将PsPR1基因转入普通烟草NC89中。经过抗性筛选和RT-PCR分子检测,获得含风PR1转基因植株。对转化烟草的T0代植株进行抗病性鉴定,发现转APRIJ基因烟草能轻微增强对烟草黑胫病的抗性,说明PsPRI基因具有抗烟草黑胫病原菌(Phytophthoraparasiticavar.nicotianae)的功能。  相似文献   

9.
利用基因工程技术 ,将分别克隆在两个不同载体上的甜味蛋白 thaum atin c DNA基因片段连接成一个完整的 c DNA基因 ,并将该基因克隆进 p BI12 1,构建成表达载体 p BI12 1- tha.通过冻融法导入农杆菌 ,农杆菌介导叶盘法转入烟草 ,经过组培 ,得到转基因的植株 .提取转基因烟草总 DNA,经 PCR,PCR- Southern和 Southern杂交证实 ,甜味蛋白基因已整合到烟草基因组中 .RT- PCR结果证明 ,thaumatin基因已在转基因烟草中转录成 m RNA,但SDS- PAGE和甜味尝试都表明 thaumatin基因在转基因烟草中没有表达出甜味蛋白  相似文献   

10.
外源RNA干涉基因在烟草中的转化及表达   总被引:1,自引:0,他引:1  
依据RNA干涉机制,以TMV复制酶基因为靶标基因,针对TMV 5个株系复制酶基因间高度同源序列设计引物,经RT-PCR反应获得靶序列,构建靶序列反向重复结构的RNA干涉双元载体.用根癌农杆菌介导将外源基因转化至烟草品种K326基因组中,培育RNA干涉转基因烟草.人工接种病毒验证转基因烟草中外源基因在植物抗病毒能力方面的表达效果,实时荧光定量PCR分析转基因烟草抗病毒能力.结果表明,实验培育的RNA干涉转基因烟草67%对TMV呈现高度抗性;荧光定量PCR分析显示,对TMV具高度抗性的转基因烟草中病毒复制酶基因转录产物mRNA存在很大程度的降解,证实了RNA干涉技术在培育抗病毒烟草品种中的效果.  相似文献   

11.
Bernard Le Foll  Tony P. George 《CMAJ》2007,177(11):1373-1380
Tobacco use is one of the leading preventable causes of death in developed countries. Adoption of approaches that have demonstrated efficacy to improve the treatment of tobacco dependence are critical to reduce the health consequences of tobacco use. We summarize the latest epidemiologic data on tobacco use, the mechanisms that underlie tobacco dependence, and advances in pharmacotherapy and nonpharmacologic interventions available for the treatment of tobacco dependence. Specifically, we discuss the use of nicotine replacement therapy, bupropion and varenicline in primary care settings.Smoking is currently responsible for the death of 1 in 10 adults worldwide, or about 5 million deaths each year. Half of the 650 million people who smoke today will eventually be killed by tobacco,1 and this morbidity and mortality can be mostly avoided if people stop smoking.2 The prevalence of smoking varies greatly around the world. Over 4.5 million people are current smokers in Canada, representing 18% of the population aged 15 years and older.3 Smoking prevalence is still high in countries such as China and India (approximately 50% and 30% respectively among males) and is on the rise in developing countries.4 Consequently, tobacco use is one of the few causes of death that is increasing globally.4In Canada and other Western countries, considerable progress has been made in decreasing tobacco use. Interestingly, there has also been a decrease in the quantity of tobacco smoked, as indicated by the number of cigarettes smoked per day (now 15.4 cigarettes on average per day among daily smokers in Canada, compared with 18.4 in 1990) and by the increasing proportion of smokers who do not smoke daily.3 Tobacco use also differs between males and females, although the gap is narrowing. In Canada, males continue to smoke more than females overall, but there is currently no significant sex-related difference in smoking prevalence among adolescents. The prevalence of tobacco use among females is increasing. This trend is alarming, since the health consequences are now affecting women at high rates: in Canada, the prevalence of lung cancer among women is now higher than that of breast cancer.  相似文献   

12.
ObjectiveTo assess the hazards at an early phase of the growing epidemic of deaths from tobacco in China.DesignSmoking habits before 1980 (obtained from family or other informants) of 0.7 million adults who had died of neoplastic, respiratory, or vascular causes were compared with those of a reference group of 0.2 million who had died of other causes.Setting24 urban and 74 rural areas of China.SubjectsOne million people who had died during 1986-8 and whose families could be interviewed.ResultsAmong male smokers aged 35-69 there was a 51% (SE 2) excess of neoplastic deaths, a 31% (2) excess of respiratory deaths, and a 15% (2) excess of vascular deaths. All three excesses were significant (P<0.0001). Among male smokers aged ⩾70 there was a 39% (3) excess of neoplastic deaths, a 54% (2) excess of respiratory deaths, and a 6% (2) excess of vascular deaths. Fewer women smoked, but those who did had tobacco attributable risks of lung cancer and respiratory disease about the same as men. For both sexes, the lung cancer rates at ages 35-69 were about three times as great in smokers as in non-smokers, but because the rates among non-smokers in different parts of China varied widely the absolute excesses of lung cancer in smokers also varied. Of all deaths attributed to tobacco, 45% were due to chronic obstructive pulmonary disease and 15% to lung cancer; oesophageal cancer, stomach cancer, liver cancer, tuberculosis, stroke, and ischaemic heart disease each caused 5-8%. Tobacco caused about 0.6 million Chinese deaths in 1990 (0.5 million men). This will rise to 0.8 million in 2000 (0.4 million at ages 35-69) or to more if the tobacco attributed fractions increase.ConclusionsAt current age specific death rates in smokers and non-smokers one in four smokers would be killed by tobacco, but as the epidemic grows this proportion will roughly double. If current smoking uptake rates persist in China (where about two thirds of men but few women become smokers) tobacco will kill about 100 million of the 0.3 billion males now aged 0-29, with half these deaths in middle age and half in old age.

Key messages

  • Of the Chinese deaths now being caused by tobacco, 45% are from chronic lung disease, 15% from lung cancer, and 5-8% from each of oesophageal cancer, stomach cancer, liver cancer, stroke, ischaemic heart disease, and tuberculosis
  • Tobacco now causes 13% (and will probably eventually cause about 33%) of deaths in men but only 3% (and perhaps eventually about 1%) of deaths in women as the proportion of young women who smoke has become small
  • Two thirds of men now become smokers before age 25; few give up, and about half of those who persist will be killed by tobacco in middle or old age
  • If present smoking patterns continue about 100 million of the 0.3 billion Chinese males now aged 0-29 will eventually be killed by tobacco
  • Tobacco caused 0.6 million deaths in 1990 and will cause at least 0.8 million in 2000 (0.7 million in men) and about 3 million a year by the middle of the century on the basis of current smoking patterns
  相似文献   

13.
The molecular processes that underlie addiction are beginning to unfold. Genetically determined variations in dopaminergic neurotransmission predispose to nicotine dependence. In addition, tobacco use is likely to be governed by the rate at which smokers metabolize nicotine. Functional polymorphisms in CYTOCHROME P450 monooxygenases that metabolize nicotine have now been defined and it should soon be possible to identify fast nicotine metabolizers by DNA analysis. Here, we review the key neurotransmitter receptors and metabolic enzymes implicated in tobacco dependence. We explore the potential benefits of classifying smokers according to the molecular aetiology of their habit. One major benefit will be in planning effective strategies for smoking cessation. Methods of typing for alleles related to smoking behavior that might be suitable for use in clinical practice in the future will also be discussed  相似文献   

14.
OBJECTIVE--To assess the hazards associated with long term use of tobacco. DESIGN--Prospective study of mortality in relation to smoking habits assessed in 1951 and again from time to time thereafter, with causes sought of deaths over 40 years (to 1991). Continuation of a study that was last reported after 20 years'' follow up (1951-71). SUBJECTS--34,439 British male doctors who replied to a postal questionnaire in 1951, of whom 10,000 had died during the first 20 years and another 10,000 have died during the second 20 years. RESULTS--Excess mortality associated with smoking was about twice as extreme during the second half of the study as it had been during the first half. The death rate ratios during 1971-91 (comparing continuing cigarette smokers with life-long non-smokers) were approximately threefold at ages 45-64 and twofold at ages 65-84. The excess mortality was chiefly from diseases that can be caused by smoking. Positive associations with smoking were confirmed for death from cancers of the mouth, oesophagus, pharynx, larynx, lung, pancreas, and bladder; from chronic obstructive pulmonary disease and other respiratory diseases; from vascular diseases; from peptic ulcer; and (perhaps because of confounding by personality and alcohol use) from cirrhosis, suicide, and poisoning. A negative association was confirmed with death from Parkinson''s disease. Those who stopped smoking before middle age subsequently avoided almost all of the excess risk that they would otherwise have suffered, but even those who stopped smoking in middle age were subsequently at substantially less risk than those who continued to smoke. CONCLUSION--Results from the first 20 years of this study, and of other studies at that time, substantially underestimated the hazards of long term use of tobacco. It now seems that about half of all regular cigarette smokers will eventually be killed by their habit.  相似文献   

15.
BackgroundLung cancer is the leading cause of cancer death in the US. While an extensive literature exists detailing lung cancer risk factors and mortality among patients with a history of tobacco use, the data are more limited among individuals who have never smoked. The purpose of this investigation is to compare survival rates between the two groups and evaluate potential risk factors among never smokers.MethodsThis retrospective study included 3380 smokers and 334 never smokers who were diagnosed with lung cancer at Stony Brook University Hospital between 2003 and 2016. 1-, 3-, 5- and 10-year survival outcomes, stratified by smoking status, were compared and Kaplan-Meier curves for overall survival are provided. Cox Proportional Hazard models were used to evaluate factors influencing survival among never smokers.ResultsNever smokers with lung cancer were more likely to be female, be diagnosed with adenocarcinoma histology, and had fewer comorbidities than lung cancer patients who smoked. Although 60% of patients were diagnosed at a later stage of disease development, regardless of smoking status, overall short- and long-term survival was significantly higher among never smokers compared to those with a history of tobacco use. In addition to age and stage at diagnosis, a history of diabetes was found to be a significant prognostic factor for decreased survival among never smokers (HR=3.15, 95% CI (1.74, 5.71)).ConclusionsData from the present investigation suggest that, regardless of smoking status, approximately three of every five lung cancer patients are diagnosed at a later stage, and that both short- and long-term survival outcomes are significantly better among never smokers compared to those with a history of tobacco use. Additional studies are required to validate these findings and better explain the mechanistic drivers for the improved outcomes among never smokers.  相似文献   

16.
《Biomarkers》2013,18(6-7):391-403
Abstract

A randomized, multi-center study of adult cigarette smokers switched to tobacco-heating cigarettes, snus or ultra-low machine yield tobacco-burning cigarettes (50/group) was conducted, and subjects’ experience with the products was followed for 24 weeks. Differences in biomarkers of tobacco exposure between smokers and never smokers at baseline and among groups relative to each other and over time were assessed. Results indicated reduced exposure to many potentially harmful constituents found in cigarette smoke following product switching. Findings support differences in exposure from the use of various tobacco products and are relevant to the understanding of a risk continuum among tobacco products.

Trial registration: ClinicalTrials.gov identifier: NCT02061917.  相似文献   

17.
The variation in lymphocyte sister-chromatid exchange (SCE) frequency as a function of time was investigated in nonsmokers and smokers. The smokers were divided into 3 groups depending on their smoking status. The group termed 'smokers' participated in a program to stop smoking but did not reduce or eliminate their use of tobacco; 'smoke enders' successfully completed the smokending program and remained free of tobacco for the duration of the study, while the 'variable' group stopped smoking for a limited time but then resumed smoking. 8 or more blood samples per person were obtained over a period of at least 12 months. The SCE frequencies for each of these groups were compared with each other and with those of two previous longitudinal study groups from our laboratory. The proportion of high-frequency cells (HFCs) was also determined for each sample. The results confirm our previous finding that SCE frequencies and the proportion of HFCs observed in separate samples from the same individual are more likely to be different as the time between samples increases. We also show that smokers have significantly more SCEs and HFCs than do nonsmokers, that SCE frequencies in smokers do not decline for at least 12 months when smoking is stopped, and that among smokers, significant seasonal variation in the SCE frequency occurs. These results provide useful information concerning the effects of smoking upon SCE frequencies, and will be helpful in designing and interpreting the results of long-term human population cytogenetic studies.  相似文献   

18.

Objective

To evaluate the safety and efficacy as a tool of smoking cessation of electronic cigarettes (e-cigarettes), directly comparing users of e-cigarettes only, smokers of tobacco cigarettes only, and smokers of both.

Design

Prospective cohort study. Final results are expected in 2019, but given the urgency of data to support policies on electronic smoking, we report the results of the 12-month follow-up.

Data Sources

Direct contact and structured questionnaires by phone or via internet.

Methods

Adults (30–75 years) were included if they were smokers of ≥1 tobacco cigarette/day (tobacco smokers), users of any type of e-cigarettes, inhaling ≥50 puffs weekly (e-smokers), or smokers of both tobacco and e-cigarettes (dual smokers). Carbon monoxide levels were tested in a sample of those declaring tobacco smoking abstinence.

Main Outcome Measures

Sustained smoking abstinence from tobacco smoking at 12 months, reduction in the number of tobacco cigarettes smoked daily.

Data Synthesis

We used linear and logistic regression, with region as cluster unit.

Results

Follow-up data were available for 236 e-smokers, 491 tobacco smokers, and 232 dual smokers (overall response rate 70.8%). All e-smokers were tobacco ex-smokers. At 12 months, 61.9% of the e-smokers were still abstinent from tobacco smoking; 20.6% of the tobacco smokers and 22.0% of the dual smokers achieved tobacco abstinence. Adjusting for potential confounders, tobacco smoking abstinence or cessation remained significantly more likely among e-smokers (adjusted OR 5.19; 95% CI: 3.35–8.02), whereas adding e-cigarettes to tobacco smoking did not enhance the likelihood of quitting tobacco and did not reduce tobacco cigarette consumption. E-smokers showed a minimal but significantly higher increase in self-rated health than other smokers. Non significant differences were found in self-reported serious adverse events (eleven overall).

Conclusions

Adding e-cigarettes to tobacco smoking did not facilitate smoking cessation or reduction. If e-cigarette safety will be confirmed, however, the use of e-cigarettes alone may facilitate quitters remaining so.

Registration Number

NCT01785537.  相似文献   

19.
ABSTRACT: BACKGROUND: Post-discharge support is a key component of effective treatment for hospitalized smokers, but few hospitals provide it. Many hospitals and care settings fax refer smokers to quitlines for follow up, however, less than half of fax-referred smokers are successfully contacted and enrolled in quitline services. "Warm handoff" is a novel approach to care transitions in which health care providers directly link patients with substance abuse problems with specialists, using face-to-face or phone transfer. Warm handoff achieves very high rates of treatment enrollment for these vulnerable groups. METHODS: The aim of this study--"EQUIP" (Enhancing Quitline Utilization among In-Patients)--is to determine the effectiveness, and cost-effectiveness, of warm handoff versus fax referral for linking hospitalized smokers with tobacco quitlines. This study employs a two-arm, individually randomized design. It is set in two large Kansas hospitals that have dedicated tobacco treatment interventionists on staff. At each site, smokers who wish to remain abstinent after discharge will be randomly assigned to groups. For patients in the fax group, staff will provide standard in-hospital intervention and will fax-refer patients to the state tobacco quitline for counseling post-discharge. For patients in the warm handoff group, staff will provide brief in-hospital intervention and immediate warm handoff: staff will call the state quitline, notify them that a warm handoff inpatient from Kansas is on the line, then transfer the call to the patients' mobile or bedside hospital phone for quitline enrollment and an initial counseling session. Following the quitline session, hospital staff provide a brief check-back visit. Costs are measured to support cost-effectiveness analyses. We hypothesize that warm handoff, compared to fax referral, will improve care transitions for tobacco treatment, enroll more participants in quitline services and lead to higher quit rates. We also hypothesize that warm handoff will be more cost-effective from a societal perspective. Outcome measures will be assessed at 1, 6, and 12-months post enrollment. DISCUSSION: If successful, this project offers a low-cost solution for more efficiently linking millions of hospitalized smokers with effective outpatient treatment--smokers that might otherwise be lost in the transition to outpatient care. Trial registration: Clinical Trials Registration NCT01305928 Key words: Tobacco use disorder, smoking cessation, hospital, randomized clinical trial.  相似文献   

20.
Squier C 《Magyar onkologia》2001,45(2):123-128
Tobacco represents the single most preventable cause of disease and death in the world today. Of 260 million male deaths in the developed world between 1950 and 2000, it is estimated that 50 million will be due to smoking. In the oral and craniofacial region tobacco use has been associated with the occurrence of cleft palate, periodontal disease and tooth loss, and a variety of soft tissue lesions including oral cancer. For example, smoking is estimated to account for 92% of cancers of the lip, oral cavity and pharynx. Few studies have examined relative efficiency of the many different approaches to tobacco control but, in general, legislative approaches such as increasing tobacco taxes and prohibiting advertising are most effective and those based on printed educational materials and cessation groups, the least effective. In all cases, advice or intervention by health care professionals ranked among the most effective non-legislative approaches to control. A very wide range of professionally-based interventions have been described, including pharmacologic interventions, behavioral approaches and group counseling. The dental profession has a unique opportunity to influence tobacco use by their patients. Its use is almost always immediately evident to the dentist or dental assistant in terms of odor, staining, poor oral hygiene or obvious oral disease. There is also a tendency for the length of personal contact with the dentist to be greater than with a physician. Guidelines are now available that provide the dental professional with advice on the best approaches to tobacco control with their patients.  相似文献   

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