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51.
薛静  王庆光 《黑龙江医学》2000,4(4):179-182
《红字》表达的深刻含义一直以来都是评论家们争论的焦点。文中从人性这个角度来诠释《红字》中3个主要的人物,探讨在清教的专制统治下,个人在自由与权威中的挣扎以及主人公在此压制下人性的发展,以此揭示作者霍桑本人的内心世界,即内心对爱的欲求以及呼吁人以极大的勇气抛弃虚伪、回归真实的人性。  相似文献   
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53.
目的:评价体外循环下不阻断升主动脉行心内直视术对心肌的保护作用。方法:对1995年9月至1998年8月在先心心内直视术中应用此法的136例婴幼儿进行回顾性分析。全组男77例,女59例。年龄3个月~5岁(平均365±120岁),体重5~18(平均1401±352)。病种包括室间隔缺损103例,房间隔缺损12例,法乐氏四联症14例,法三2例,肺动脉瓣狭窄2例,部分性房室管通道2例,三尖瓣下移1例。结果:全组死亡3例(22%)。术后并发症:低心排2例,支气管痉挛3例,二次止血1例。结论:体外循环下不阻断升主动脉行心内直视术是临床效果满意,安全有效的心肌保护方法。  相似文献   
54.
本研究采用右前外侧切口不阻断主动脉体外循环的方法对57例心脏病人施行了心内直视手术。结果表明,一例房缺病人因引流多而再次开胸止血,另一例法乐氏四联症术后残余分流者术中修补不满意,其余效果良好,无手术死亡及术后住院死亡,无伤口感染发生;也解决了长期以来许多女性病人因正中切口显眼的瘢痕所造成的心理压力,取得良好的手术美容效果。  相似文献   
55.
Kim WG  Park SS 《Artificial organs》1999,23(4):369-372
A standardized system to describe the pressure-flow characteristics of a given cannula has recently been proposed and has been termed the M-number system. Using 3 different sizes of aortic cannulas in 50 pediatric cardiac patients on hypothermic cardiopulmonary bypass, we analyzed the correlation between experimentally and clinically derived M-numbers and found it to be positive. Clinical M-numbers were typically 0.35 to 0.55 greater than experimental M-numbers and correlated inversely with a patient's temperature change; this was most probably due to increased blood viscosity arising from hypothermia. This inverse relationship was more marked in higher M-number cannulas. The clinical data obtained in this study suggest that the experimentally derived M-number correlates strongly with the clinical performance of the cannula and that the influence of temperature is significant.  相似文献   
56.
Objective. To evaluate the utility of the iSTAT blood analyzer, a bedside device for hematocrit, sodium, potassium, and glucose measurement during cardiopulmonary bypass (CPB).Methods. Forty patients scheduled for elective CPB were evaluated prospectively. In addition to using the iSTAT analyzer, blood samples were analyzed at four time points: following induction of anesthetic, 10 min. after initiation of CPB, 60 min. after initiation of CPB, and following heparin neutralization by protamine. Blood glucose concentration was measured by the hospital laboratory using a Kodak Analyzer and by a glucose meter, electrolytes were evaluated by the Kodak Analyzer and BGE (a device which is commonly used for satellite laboratory determinations of electrolyte and blood gas results), and hematocrit samples were measured by the hospital laboratory using an NE 8,000 and a centrifuge. The means and standard deviations of the differences between the methods were calculated.Results. The hematocrit values determined by the iSTAT machine, when adjusted for the level of total protein (according to manufacturer's directions), differed from the laboratory values by 0.53 = 1.46 percentage points. An alternative to measuring total protein and making the adjustment is simply adding 1 % to the hematocrit in the pre-CPB period and 3% on-CPB or post-CPB, which we found to yield values that differed from the laboratory by 0.52 ± 1.42 percentage points. For all four tests (hematocrit, sodium, potassium, and glucose) the iSTAT had a similar relationship to the laboratory values as did the other commonly used means (centrifuge, BGE, and glucose meter) of clinical evaluation.Conclusion. In summary, we found that in patients undergoing CPB, the iSTAT values agreed sufficiently well with standard laboratory values and that the iSTAT instrument can be relied upon for bedside measurements.Presented in part at the Annual Meeting of the Society of Cardiovascular Anesthesiologists, Philadelphia, PA, May 1995, and at the 70th meeting of the IARS, Washington DC, March 1996. Supported in part by a grant by iSTAT Corporation.  相似文献   
57.
Emboli and Neuropsychological Outcome Following Cardiopulmonary Bypass   总被引:4,自引:0,他引:4  
The dramatic decline in mortality related to cardiac surgery has resulted in over 330,000 surgeries involving cardiopulmonary bypass (CPB) being performed yearly in the United States. Although few patients die as a result of cardiac surgery, over two thirds of the patients demonstrate evidence of acute neuropsychological dysfunction postoperatively. The potential mechanisms contributing to post-CPB neuropsychological deficits are many, but two major inter-related etiologic factors, hypoperfusion and emboli, are suggested as the probable culprits. If embolism is the cause of the deficits, increasing cerebral perfusion would deliver more emboli and increase the amount and severity of injury. Conversely, if hypoperfusion is the cause of the injury, then decreasing brain blood flow to minimize embolic delivery would increase the likelihood of perfusion injury. By monitoring the carotid arteries of patients undergoing coronary artery bypass graft surgery, we have determined the frequency and quantity of embolic signals that occur during CPB. Although we have not been able to determine the nature of the embolus, gaseous or solid, we have demonstrated a relationship between the overall embolic load and the probability of having NP dysfunction.  相似文献   
58.
Summary The uterine inhibitory effect and potential maternal and fetal side effects of two -mimetic compounds, ritodrine hydrochloride and fenoterol hydrobromide, were compared in a randomized trial. The drugs were administered by intravenous infusion to 24 healthy term nulliparous women during effective first-stage labour; each of them received fenoterol (1, 2, or 4 µg/min) or ritodrine (100, 200, or 400 µg/min). There was no difference between the drugs in the intensity of the uterine inhibition. However, for a similar inhibitory effect, the duration of tocolysis was longer after ritodrine. During the intrapartum and neonatal periods, neither compound induced any change in the fetal parameters investigated, and their effects on maternal parameters were comparable.  相似文献   
59.
Triiodothyronine (T3) and Cardiovascular Therapeutics: A Review   总被引:1,自引:0,他引:1  
Hypothyroidism is associated with an abnormal hemodynamic state characterized by decreased heart rate, stroke volume, output, and contractility, and increased systemic vascular resistance. Since cardiopulmonary bypass (CPB) and surgical stress can induce profound decreases in triiodothyronine (T3) levels, the hemodynamic consequences of "stress-induced" hypothyroidism and T3 repletion are of increasing clinical interest. Available data generally support the likelihood of a beneficial effect associated with T3 replacement in brain-dead organ donors and in cases of low cardiac output following CPB. Although hypotheses have been advanced to account for these salutary effects, the mechanism by which T3 may augment hemodynamic performance has not been precisely defined, particularly in the acute setting. Although additional research is needed to clarify these and other issues, preliminary findings with T3 replacement indicate that such investigation is warranted.  相似文献   
60.
目的 重点讨论手术方式对老年性胃癌根治术预后的关系。 方法  回顾分析 1995年 1月~2 0 0 0年 1月共收治的 83例 6 5岁以上老年性胃癌根治术随访 3年 ,分析手术方式和心肺合并症的关系及其对死亡的影响。 结果  三年后U区癌心肺合并症死亡 2 6例 (2 6 / 83,31 1% ) ,M区癌心肺合并症死亡 2例 (2 / 83,2 4 % ) ,L区癌心肺合并症死亡 8例 (8/ 83,9 6 % ) ,M区和L区共计 10例 (10 / 83,12 % )。两组 (U区与M +L区 )死亡率相比有显著差异 ,P <0 0 1。 结论 U区开胸手术易引起心肺合并症 ,是老年性胃癌根治术后死亡率增高的主要原因。  相似文献   
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