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41.
Background: Smoking is considered to be a risk factor for patients undergoing surgery and anesthesia, but it is unclear whether this is applicable to patients undergoing ambulatory surgery. The aim of this study was to determine the risk of respiratory complications and wound infection among smokers.

Methods: The authors studied a random selection of 489 adult patients undergoing ambulatory surgery. Smoking status was determined by self-report and confirmed with end-expired carbon monoxide analysis. The risk of respiratory complications (i.e., desaturation, cough, laryngospasm, bronchospasm, breath-holding, or apnea) and wound infection (i.e., wound redness or discharge +/- positive microbial culture, requiring antibiotic therapy) in smokers versus nonsmokers was ascertained. Odds ratios were estimated from multivariable logistic regression and adjusted for age, gender, body mass index, partner's smoking status, domiciliary smoking exposure, and extent and duration of surgery.

Results: Most smokers continued to smoke up until the day of surgery. Smokers had a higher rate of respiratory complications (32.8%vs. 25.9%; adjusted odds ratio, 1.71; 95% confidence interval, 1.03-2.84;P = 0.038) and wound infection (3.6%vs. 0.6%; odds ratio, 16.3; 95% confidence interval, 1.58-175;P = 0.019). Odds ratios comparing current plus ex-smokers with nonsmokers were of similar magnitude for most of these complications.  相似文献   

42.
Background: Anesthetic preconditioning (APC) with sevoflurane reduces myocardial ischemia-reperfusion injury. The authors tested whether two brief exposures to sevoflurane would lead to a better preconditioning state than would a single longer exposure and whether dual exposure to a lower (L) concentration of sevoflurane would achieve an outcome similar to that associated with a single exposure to a higher (H) concentration.

Methods: Langendorff-prepared guinea pig hearts were exposed to 0.4 mm sevoflurane once for 15 min (H1-15; n = 8) or 0.4 mm (H2-5; n = 8) or 0.2 mm sevoflurane (L2-5; n = 8) twice for 5 min, with a 5-min washout period interspersed. Sevoflurane was then washed out for 20 min before 30 min of global no-flow ischemia and 120 min of reperfusion. Control hearts (n = 8) were not subjected to APC. Left ventricular pressure was measured isovolumetrically. Ventricular infarct size was determined by tetrazolium staining and cumulative planimetry. Values are expressed as mean +/- SD.

Results: The authors found a better functional return and a lesser percentage of infarction on reperfusion in H2-5 (28 +/- 9%) than in H1-15 (36 +/- 8%; P < 0.05), L2-5 (43 +/- 6%; P < 0.05), or control hearts (52 +/- 7%; P < 0.05).  相似文献   

43.
Parkinson's disease is a neurodegenerative movement disorder that results from progressive loss of midbrain dopamine neurons, which consequently leads to hyperactivity of subthalamic neurons.  相似文献   
44.
作者采用双眼视差视觉诱发电位(VEP)记录了18名正常人和9名斜视患者(立体盲),结果正常人视觉刺激VEP P100振幅明显高于非视差刺激者;斜视患者视差刺激与非视差刺激VEP P100振幅差异无显著性;正常人视差刺激VEP P100振幅增加的幅度值[(DSA-NDA)/NDA]明显高于斜视患者。 (中华眼底病杂志,1992,8:10-13)  相似文献   
45.
INTRODUCTION Parkinson抯 disease (PD), a debilitating neurodegenerative disorder, is featured with bradykinesia, resting, muscular rigidity, gait disturbances, and postural reflex impairment[1]. PD is rare before age of 50 years, but it increases dramatically with older ages, with peak onset occurring during the age of 70-85 years. In the United States, prevalence of PD in all age groups is approximately 150 per 100 000 and is roughly 30 per 100 000 at age of less than 50 years and 800 …  相似文献   
46.
Background: Septic shock is associated with vasopressin deficiency and a hypersensitivity to its exogenous administration. The goal of the current study was to determine whether short-term vasopressin infusion in patients experiencing severe septic shock has a vasopressor sparing effect while maintaining hemodynamic stability and adequate end-organ perfusion.

Methods: Patients experiencing septic shock that required high-dose vasopressor support were randomized to a double-blinded 4-h infusion of either norepinephrine (n = 11) or vasopressin (n = 13), and open-label vasopressors were titrated to maintain blood pressure. To assess end-organ perfusion, urine output and creatinine clearance, gastric mucosal carbon dioxide tension, and electrocardiogram ST segment position were measured.

Results: Patients randomized to norepinephrine went from a median prestudy norepinephrine infusion of 20.0 [mu]g/min to a blinded infusion of 17.0 [mu]g/min at 4 h, whereas those randomized to vasopressin went from a median prestudy norepinephrine infusion of 25.0 [mu]g/min to 5.3 [mu]g/min at 4 h (P < 0.001). Mean arterial pressure and cardiac index were maintained in both groups. Urine output did not change in the norepinephrine group (median, 25 to 15 ml/h) but increased substantially in the vasopressin group (median, 32.5 to 65 ml/h;P < 0.05). Similarly, creatinine clearance did not change in the norepinephrine group but increased by 75% in the vasopressin group (P < 0.05). Gastric mucosal carbon dioxide tension and electrocardiogram ST segments did not change significantly in either group.  相似文献   

47.
48.
中药材龟板和鳖甲中DNA的提取与扩增   总被引:22,自引:0,他引:22  
中药材龟板和鳖甲中DNA的提取与扩增王亚明,周开亚,吴平,徐珞珊(南京师范大学生物系,南京210097;中国药科大学生药学研究室,南京210009)龟鳖类药材在我国使用历史悠久,具补阴益气的功效。《中国药典》(1990年版)规定龟甲(龟板)的原动物为...  相似文献   
49.
目的:研究视网膜下液(subrefinal fluid,SRF)对增殖性玻璃体视网膜病变(proliferativeVitreoretinopathy,PVR)的多种细胞增殖的影响. 方法;采用直接细胞计数和3H-TdR掺入率测定DNA合成两种方法观察28例孔源性视网膜脱离患者SRF对培养的人视网膜色索上皮(retinal pigment epithelium,RPE)细胞,视网膜神经胶质(retinal glia,RG)细胞及成纤维细胞(flbroblast,FB)生长刺激作用. 结果:所有标本均具有刺激RPE细胞、RG细胞及FB增殖和DNA合成能力,增殖率范围分别在基线上52.5%~233.3%、36.4%~177.8%、55.4%~277.8%之间.SRF促细胞增殖串在三种细胞间比较无显著差异。 结论:SRF具有促多种细胞增殖的能力,推测SRF中含有促细胞增殖的活性物质。 (中华眼底病杂志,1996,12:233-235)  相似文献   
50.
分析57例视网膜脱离术后视网膜不复位26例,复位后再脱离31例,手术失败的原因,发现原裂孔未闭、新裂孔形成和增殖性玻璃体视网膜病变是视网膜脱离术后未复位或再脱离的三大原因,并分析了造成这些原因的因素,讨论了有关再手术的问题。 (中华眼底病杂志,1993,9:164-165)  相似文献   
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