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101.
102.
硬膜外应用局麻药为手术提供麻醉与镇痛,同时胸段硬膜外麻醉与镇痛也被广泛应用于心脏,大血管,胸部和腹部的手术中.它不仅可以加快病人麻醉后的苏醒,而且可以提供很好的术后镇痛.除了上述优点,许多基础及临床研究发现硬膜外麻醉还有许多其它方面的作用,如:减轻神经内分泌系统的应激反应、减少围术期并发症的发生,以及通过暂时性的阻滞胸交感神经提供心肺及胃肠道的保护作用,改善免疫和凝血功能.本文就近年来胸段硬膜外麻醉应用及研究进展作一综述.  相似文献   
103.
目的:探索全麻复合硬膜外麻醉和全身麻醉用于子宫切除术对血液动力学的影响。方法:36例行子宫切除术患者,随机分成全麻组(A组,18例)和硬膜外+全麻组(B组,18例),采用Swan-Ganz导管技术,监测手术时血液动力学变化。结果:A组HR、MAP、CVP、SVR及CI均明显增加,SV无明显变化;B组除CVP明显上升外,其余各指标均无明显变化。结论:全麻复合硬膜外麻醉下施行子宫切除术,能减轻术中应激反应,稳定血液动力学。  相似文献   
104.
目的:评价全程心理疏导预防全身麻醉术后导尿管刺激躁动的临床效果。方法:全麻下实施胆囊切除手术的80例男性患者为观察对象,随机均分为全程心理疏导组(Ⅰ组)和对照组(Ⅱ组),每组40例。Ⅰ组:术前、麻醉诱导前、苏醒后均对患者施行个体化心理疏导,根据患者具体情况进行沟通,解除其焦虑与恐惧心理。Ⅱ组:常规访视,不进行全程心理疏导。飞利浦多功能监测仪连续监测ECG、HR、SpO2及每3分钟监测一次BP,记录入室后MAP、HR的基础值(T0)、术毕(T1)、拔管后3 min(T2)、10 min(T3)、20min(T4)的血流动力学变化,观察记录拔管后患者因尿管刺激引发躁动评分。结果:Ⅰ组患者苏醒期对尿管刺激反应程度明显低于Ⅱ组,患者在苏醒期血压、心率也较稳定。结论:全程心理疏导可以预防、减轻全麻术后因导尿管刺激而引发的躁动。  相似文献   
105.
doi: 10.1111/j.1741‐2358.2011.00545.x Nutritional status, dietary intake and oral quality of life in elderly complete denture wearers Background and objective: The prevalence of malnutrition increases with age because of many factors. Edentulousness leads to the avoidance of many types of foods. The aim of this study was to determine whether elderly complete denture wearers have a higher risk of malnutrition than dentate controls. Material and methods: A Mini‐Nutritional Assessment (MNA) and a 3‐day dietary record were compiled for a group of fully dentates (21 women and 29 men; mean age 70.1 ± 6.1) and for a group of complete denture wearers (31 women and 16 men; mean age 70.1 ± 8.1). Socio‐demographic data and scores on the General Oral Health Assessment Index (GOHAI) questionnaire were collected. Results: Inter‐group comparison of MNA scores showed that more subjects in the edentulous group (21.3%) risked malnutrition than in the dentate group (0%). The variability of the MNA could be explained for 22% by dental status, 7% by loneliness and 4% by the GOHAI score (regression analysis). Both groups had insufficient energy intakes and deficits in vitamins and micronutrients; moreover, edentulous subjects had lower intakes than dentate subjects. Conclusion: The use of conventional dentures increases the risk of malnutrition in the elderly.  相似文献   
106.
Redhorse, Moxostoma spp., are considered to be negatively affected by dams although this assertion is untested for Canadian populations. One hundred and fifty-one sites in the Grand River watershed were sampled to identify factors influencing the distribution of redhorse species. Individual species of redhorse were captured from 3 to 32% of sites. The most widespread species were golden redhorse, M. erythrurum (30%) and greater redhorse, M. valenciennesi (32%), while river redhorse, M. carinatum, was only found along the lower Grand River. Redhorse were absent from the highly fragmented Speed River sub-watershed and upper reaches of the Conestogo River and the Grand River. Redhorse species richness was positively correlated to river fragment size and upstream drainage area. Generalized additive models (GAMs) were applied to evaluate the influence of river fragment length, connectivity and habitat on species distribution. Principal component analysis reduced habitat data to three axes representing: channel structure, substrate, and pool, riffle and run habitats (PC1); gradient and drainage area (PC2); and cover (PC3). GAMs indicate that PC2 was important for predicting black redhorse and greater redhorse site occupancy and PC1 was important for golden redhorse. River fragment length was important for predicting site occupancy for shorthead redhorse, but not other species.  相似文献   
107.
Between October and December of 1996–1999, off eastern Antarctica (60°-150°E), we darted 31 crabeater seals with midazolam and pethidine at estimated dose rates of 0.15–0.4 mg/kg and 1–3 mg/kg, respectively. Maximum sedation was reached at 23 ± 9 min (n = 18) and first signs of recovery were noted at 54 ± 24 min (n = 4). Seals greater than 250 kg body-mass were sedated by administration of approximately 90–100 mg midazolam and 600 mg pethidine, but the degree of sedation was unpredictable and did not permit invasive procedures in some cases. Behavior of the seal and adjacent conspecifics affected the success of procedures and our ability to monitor vital signs. Naloxone and flumazenil reversed sedation, making this combination attractive for use in animals adjacent to water. Additional ketamine was administered to two seals, resulting in improved restraint.  相似文献   
108.
109.
Oxidative stress causes damage to nucleic acids, membrane lipids and proteins. One striking effect is the metal-catalyzed, site-specific carbonylation of proteins. In the gram-positive soil bacterium Bacillus subtilis, the PerR-dependent specific stress response and the B-dependent general stress response act together to make cells more resistant to oxidative stress. In this study, we analyzed the carbonylation of cytoplasmic proteins in response to hydrogen peroxide stress in B. subtilis. Furthermore, we asked whether the B-dependent response to oxidative stress also confers protection against protein carbonylation. To monitor the amount and specificity of protein damage, carbonyls were derivatized with 2,4-dinitrophenylhydrazine, and the resulting stable hydrazones were detected by immunoanalysis of proteins separated by one- or two-dimensional gel electrophoresis. The overall level of protein carbonylation increased strongly in cells treated with hydrogen peroxide. Several proteins, including the elongation factors EF-G, TufA and EF-Ts, were found to be highly carbonylated. Induction of the peroxide specific stress response by treatment with sub-lethal peroxide concentrations, prior to exposure to otherwise lethal levels of peroxide, markedly reduced the degree of protein carbonylation. Cells starved for glucose also showed only minor amounts of peroxide-mediated protein carbonylation compared to exponentially growing cells. We could not detect any differences between wild-type and sigB cells starved for glucose or preadapted by heat treatment with respect to the amount or specificity of protein damage incurred upon subsequent exposure to peroxide stress. However, artificial preloading with proteins that are normally induced by B-dependent mechanisms resulted in a lower level of protein carbonylation when cells were later subjected to oxidative stress.Communicated by W. Goebel  相似文献   
110.
For many years, the expression "cutoff effect of anesthesia," has been used to denote the failure of the higher alcohols or paraffins to produce anesthesia. As such, it is used to assess the plausibility of specific models, proposed for anesthesia. However, the uses were shown, in many respects, to be problematic. This article augments the notion of the cutoff to fit for all cases in which only some of the molecules in a homologous series are anesthetics. We find that the location of the cutoff points is affected by three free energy quantities: that of the adsorption of the agent to the anesthetic "site" (f(sl,site)), that of the perturbation of the site (f(ll,site)), and that of the evaporation of the agent from its pure condensed phase (Deltamu degrees (evaporation)). This outcome indicates that the cutoff cannot be attributed to a single parameter. In addition, the analyses that attribute the cutoff to the failure of compounds to obey the much-used Meyer-Overton correlation will have to be amended. This article shows that cutoff results can be used to elucidate the structure of a site.  相似文献   
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