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71.
Iodine 123 N-isopropyl p-iodoamphetamine (123I-IMP), originally developed as a brain scanning agent, is also taken up by the lung. To evaluate the effects of cigarette smoking on the kinetics of IMP in the lung, we studied 123I-IMP clearance from the lung in 18 volunteers (8 non-smokers and 10 smokers). After the injection of 111 MBq of 123I-IMP into the medial cubital vein, the time-activity curve for 60 min and the regional activity using 1 frame per minute and a 64 × 64 matrix were obtained. The 123I-IMP clearance curve was described as follows: C (t) = A 1ek 1 t+ A 2ek 2 t (A1, A 2: intercepts, and k 1, k 2: slopes of the exponential components). 123I-IMP clearance was delayed in smokers, and k 2 was smaller in smokers. Also, a correlation between k 1, k 2, and the number of cigarettes smoked per day was found (r = –0.65, r = –0.74, respectively, P<0.01). In conclusion, this study suggests that the delayed clearance and retention of 123I-IMP in the lung indicate lung metabolic disorders due to cigarette smoking.Offprint requests to: K. Kato  相似文献   
72.
The Middle East (ME) is an ethnically and economically diverse region. A systematic review of all stroke studies conducted in the ME was carried out, with the aim of determining the prevalence of classic vascular risk factors (CRFs) across this region. Additionally, the prevalence of CRFs in the ME was compared to that of a US cohort. Prospective and retrospective ME stroke studies published from 1994 to 2014 were searched for that specifically reported on the prevalence of CRFs. The Z test for proportions was used to determine the significance of differences in CRF rates between the ME and non‐ME studies. A total of 21 724 stroke patients from 13 nations in the ME were included. The prevalence rates for CRFs in the ME stroke population were hypertension, 62.1%; diabetes, 33.1%; dyslipidaemia, 36.8%; ischaemic heart disease, 24.6%; smoking, 19.3%; and atrial fibrillation, 13.6%. Compared to the US cohort, ME patients had a lower prevalence of all CRFs except diabetes (< 0.0001) and smoking (P = 0.05). Compared with stroke patients in the USA, those in the ME have a significantly higher prevalence of diabetes and smoking. Education and lifestyle modification is perhaps the most effective strategy in reducing the risk of stroke in this population.  相似文献   
73.
Amyotrophic lateral sclerosis (ALS) is a multilevel disease of the motor neuron system. The mechanisms triggering disease onset should be considered separately from those facilitating its spread and motor neuron death. In 2005, I brought together clinical and epidemiological evidence to support the hypothesis that acquired nucleic acid changes may trigger sporadic ALS. Since 2005, the conceptual foundations for this hypothesis have been strengthened. The journal Amyotrophic Lateral Sclerosis was renamed Amyotrophic Lateral Sclerosis & Frontotemporal Degeneration. The focal onset, with simultaneous initial maximal upper and lower motor neuron involvement in the region of onset, and patterns of spread, were characterized further. Clues from the epidemiology of sporadic ALS were affirmed by quantitative analysis, including the increase in disease incidence with age, suggesting accrual of time‐dependent changes, and the confirmation of smoking as an established risk factor. Additional observations support the conclusion that accrued somatic mutations trigger onset of ALS. Muscle Nerve 53 : 842–849, 2016  相似文献   
74.
目的 了解武警某部战士吸烟现状及对吸烟的相关认知、态度及行为倾向,为有针对性地开展部队控烟工作提供参考.方法 利用自行设计的吸烟问卷调查表,调查武警某部260名集训新兵及217名老兵的吸烟现状及对吸烟的危害认知、态度及行为倾向,并分析它们之间的关系.结果 战士总体吸烟率为37.32%(178/477),老兵吸烟率62....  相似文献   
75.
目的:研究香烟烟雾对雄性大鼠性功能的影响。方法:30只SD雄性大鼠随机均分为两组,吸烟组制备大鼠吸烟模型,使用市售红金龙过滤咀香烟(每支焦油含量13mg),吸烟组每日使其被动吸烟4次,每次两支,每次30min持续60d;对照组正常饲养。实验结束前1周两组动物笼中分别放入5只雌性大鼠,采用24h监控录像监测观察骑跨动作1周,60d后处死取标本。测定大鼠血中睾酮水平及阴茎海绵体组织一氧化氮合酶(NOS)的活性,行阴茎海绵体组织的Masson染色图像分析。结果:吸烟组大鼠骑跨动作次数减少,血中睾酮水平明显降低(P<0.05),阴茎海绵体组织NOS活性及平滑肌面积显著降低(P<0.05),胶原纤维明显增加,海绵窦血管腔有明显变化。结论:吸烟组大鼠阴茎勃起功能受到明显影响,睾酮水平降低及阴茎海绵体组织NOS活性降低、阴茎海绵体平滑肌面积的减少可能是其重要的发病机制。  相似文献   
76.
目的:探讨吸烟对大鼠生精细胞发育的影响。方法:自制吸烟机将大鼠制成被动吸烟模型,大鼠随机分成被动吸烟组(A、B组各10只)及相应对照组(C、D组各10只),A、B组被动吸烟8周,随后处死A组及相应对照组C组大鼠;B组停止被动吸烟后与其相应对照组D组继续观察48 d后处死。流式细胞术(FCM)检测各组大鼠生精细胞周期,放免法测定血睾酮(T)、黄体生成素(LH)水平,HE染色观察睾丸组织结构变化,透射电镜观察睾丸超微结构改变。结果:与C组比较,A组大鼠精子、精子细胞[(18.76±3.58)%]和初级精母细胞[(5.71±1.18)%]明显减少(P均<0.01),而精原细胞[(55.98±5.35)%]增加(P<0.01),增殖指数降低(P<0.01)。A组大鼠生精小管壁变薄,层次减少,生精小管内精原细胞减少,精母细胞固缩。间质细胞内质网扩张脱颗粒,高尔基复合体减少,支持细胞脂滴和溶酶体增多。A组大鼠T、LH水平低于C组(P均<0.01)。B组大鼠停止被动吸烟后,精子、精子细胞、初级精母细胞比例和增殖指数上升,T、LH水平升高,但仍低于D组。结论:吸烟导致大鼠睾丸生精上皮损伤及间质细胞和支持细胞受损,同时伴有T和LH水平的下降,延缓生精细胞增殖,停止吸烟后生精功能有逐渐恢复的趋势。  相似文献   
77.
Abstract:  The purpose of this study was to assess the predictive value of smoking history on breast cancer diagnosis in a referral clinic population. We conducted a case–control study using clinical data collected on 8,097 female patients (1,225 breast cancer cases and 6,872 controls) seen in the Mayo Clinic Breast Clinic between August 1, 1993 and November 31, 2003. Breast cancer patients and noncancer patients significantly differed with respect to age at time of the index visit (p < 0.001), number of pregnancies (p = 0.006), number of live births (p = 0.002), vital status at last known follow-up (p < 0.001), current menstruation (p < 0.001), age at menopause (p < 0.001), history of hysterectomy (p < 0.001), use of oral contraception (p = 0.05), duration of oral contraception use (p = 0.001), use of other exogenous hormones (p < 0.001), duration of exogenous hormone use (p = 0.05), breast pain at time of index visit (p = 0.002), smoking status (p < 0.001), and use of five or more alcoholic beverages per week (p = 0.002). After adjustment for these baseline characteristics, having a personal history of smoking was found to be predictive of breast cancer diagnosis (odds ratios [OR] = 1.25, p = 0.004). Other positive predictors for breast cancer diagnosis were: age (OR = 1.02, p < 0.001), history of hysterectomy (OR = 0.66, p < 0.001), prior use of oral contraception for more than 11 years (OR = 2.10, p < 0.001), and prior use of other exogenous hormones/estrogen (OR = 1.81, p < 0.001). In this referral practice having a personal history of smoking is predictive of breast cancer diagnosis. Further studies are needed to further explore this relationship.  相似文献   
78.
目的:探讨Ⅰ相代谢酶细胞色素P450 2E1(CYP2E1)基因RsaⅠ和PstⅠ位点多态性及吸烟、饮酒习惯与前列腺癌(PCa)发病风险的关系,并探讨基因与生活习惯在PCa发病中的联合作用。方法:采用PCR-RFLP技术检测109例原发性PCa患者及202例年龄匹配的男性非肿瘤患者外周血CYP2E1基因RsaⅠ和PstⅠ多态位点的基因型。结果:深吸烟(OR=2.29,95%CI:1.28~4.09)、重度吸烟史(OR=1.81,95%CI:1.02~3.22)等生活习惯为PCa易感因素。CYP2E1 C1/C1基因型与PCa易感性有显著相关(OR=1.71,95%CI:1.04~2.82),且与饮酒的联合作用明显与PCa易感性相关(OR=2.21,95%CI:1.06~4.59)。重度吸烟人群中,携带CYP2E1易感基因型(C1/C1)与不吸烟且携带非易感基因型(C1/C2或C2/C2)个体相比PCa的发病风险显著增高(OR=2.80,95%CI:1.20~6.56)。结论:携带CYP2E1易感基因型(C1/C1)并有烟酒嗜好者PCa的发病风险显著增高,且与烟草的暴露呈显著剂量反应关系。  相似文献   
79.
80.
BACKGROUND: Smoking increases the risk of end-stage renal failure in patients with primary renal disease. Whether and to what extent smoking affects the kidneys in diabetic patients with normal renal function and variable degrees of proteinuria has not been fully studied. METHODS: We followed 185 patients with type 1 or 2 diabetes mellitus and with or without signs of overt renal disease for at least 3 years, median 5.1 (3-6.8) years. Each patient had a baseline visit and at least four follow-up visits (average 4.8+/-0.3). Cases were patients who were smoking (n = 44) at the time the survey was started. Controls were patients who had never smoked (n = 141). Glomerular filtration rate (GFR) was estimated using the MDRD formula. Multiple logistic regression was used to correct for confounding factors. RESULTS: At baseline, smokers were younger (47+/-14 vs 54+/-16 years, P < 0.01), and had a lower GFR (95+/-26 ml/min) than non-smokers (107+/-33 ml/min, P < 0.05). Mean GFR remained constant during follow-up in non-smokers (106+/-31 ml/min), but decreased significantly in smokers (83+/-22 ml/min, P < 0.0001), and this relationship persisted when adjusted for retinopathy, glycaemic control, age, body habitus, ACE-inhibitor treatment, blood pressure control or severity of proteinuria. The effect of smoking on GFR decline was stronger in patients with type 1 diabetes or male gender. CONCLUSIONS: Cigarette smoking causes a decrease in GFR in diabetic patients with normal or near-normal renal function, independent of confounding factors including severity of proteinuria. The latter finding suggests a mechanism independent of glomerular damage.  相似文献   
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