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121.
美国萨维奇拉皮兹(Savage Rapids)坝自1921年动工兴建以来,鱼类如何过坝一直是专家关注的焦点。经研究,最终决定于2006年10月开始拆除这座有88 a历史的大坝。该项工程于2006年10月开工,并于2009年11月完工,随后新建了灌溉分流设施,结果不仅恢复了溯河鱼类通道,而且促进了当地经济发展。  相似文献   
122.
伍翔  梁溪沙 《商场现代化》2007,(28):365-366
随着电子信息技术的普及,实行会计电算化的企业越来越多。会计电算化的实施,也给企业的内部控制带来了许多新的问题和挑战。严格的内控制度是会计电算化信息真实可靠的重要保证,有助于防止违规、违法行为的发生,因而建立一整套适合电算化会计系统的内部控制制度就显得尤为重要。本文拟从会计电算化系统的角度,研究内部会计控制制度的有关问题及对策。  相似文献   
123.
本文简述了美国新近研制的一种卫星定位系统STARFIX的工作原理、系统组成、优缺点以及使用场合,并与美国现有的和将来使用的其他几种定位系统作了比较。文章给出了系统原理图、分系统方框图和性能比较表。  相似文献   
124.
An applicant's electrocardiogram contains a low amplitude P, QRS and T wave pattern in lead I. The diagnostic and prognostic implications of this ECG pattern are discussed.  相似文献   
125.
The evaluation of a nonsustained wide QRS tachycardia in a life insurance applicant's exercise test presents a special challenge to the medical director because of the unpredictable and potentially lethal nature of these arrhythmias. Ventricular tachycardia accounts for up to 80% of wide QRS tachycardias in unselected populations and more than 95% of cases with a prior myocardial infarction. Malignant ventricular arrhythmias usually occur in the presence of significant structural heart disease. In this setting, ventricular arrhythmias carry a high risk of sudden cardiac death. Less commonly, ventricular tachycardia occurs in hearts that appear normal. In many such cases, however, the heart is in fact not normal, but rather has less visible abnormalities including derangements of cardiac ion channels or structural proteins. In these individuals, ventricular arrhythmias also carry a high risk of sudden cardiac death. There are, however, some ventricular tachycardia syndromes which occur in normal hearts that have a more benign prognosis.  相似文献   
126.
The presence of unexpected Q waves in an applicant's electrocardiogram poses a diagnostic dilemma for the medical director. On the one hand, the Q waves may be the remnants of a previously unsuspected "silent" myocardial infarction. Conversely, unexpected Q waves may represent a normal or positional variant, or an important noncoronary type of heart disease. This case study illustrates some of the pitfalls in interpreting applicants' electrocardiograms containing Q waves in the inferior leads.  相似文献   
127.
Gilkey R  Kilts C 《Harvard business review》2007,85(11):53-4, 56, 58 passim
Recent neuroscientific research shows that the health of your brain isn't, as experts once thought, just the product of childhood experiences and genetics; it reflects your adult choices and experiences as well. Professors Gilkey and Kilts of Emory University's medical and business schools explain how you can strengthen your brain's anatomy, neural networks, and cognitive abilities, and prevent functions such as memory from deteriorating as you age. The brain's alertness is the result of what the authors call cognitive fitness -a state of optimized ability to reason, remember, learn, plan, and adapt. Certain attitudes, lifestyle choices, and exercises enhance cognitive fitness. Mental workouts are the key. Brain-imaging studies indicate that acquiring expertise in areas as diverse as playing a cello, juggling, speaking a foreign language, and driving a taxicab expands your neural systems and makes them more communicative. In other words, you can alter the physical makeup of your brain by learning new skills. The more cognitively fit you are, the better equipped you are to make decisions, solve problems, and deal with stress and change. Cognitive fitness will help you be more open to new ideas and alternative perspectives. It will give you the capacity to change your behavior and realize your goals. You can delay senescence for years and even enjoy a second career. Drawing from the rapidly expanding body of neuroscience research as well as from well-established research in psychology and other mental health fields, the authors have identified four steps you can take to become cognitively fit: understand how experience makes the brain grow, work hard at play, search for patterns, and seek novelty and innovation. Together these steps capture some of the key opportunities for maintaining an engaged, creative brain.  相似文献   
128.
Companies often begin their search for great ideas either by encouraging wild, outside-the-box thinking or by conducting quantitative analysis of existing market and financial data and customer opinions. Those approaches can produce middling ideas at best, say Coyne, founder of an executive-counseling firm in Atlanta, and Clifford and Dye, strategy experts at McKinsey. The problem with the first method is that few people are very good at unstructured, abstract brainstorming. The problems with the second are that databases are usually compiled to describe current--not future--offerings, and customers rarely can tell you whether they need or want a product if they've never seen it. The secret to getting your organization to regularly generate lots of good ideas, and occasionally some great ones, is deceptively simple: First, create new boxes for people to think within so that they don't get lost in the cosmos and they have a basis for offering ideas and knowing whether they're making progress in the brainstorming session. Second, redesign ideation processes to remove obstacles that interfere with the flow of ideas--such as most people's aversion to speaking in groups larger than ten. This article offers a tested approach that poses concrete questions. For example, what do Rollerblades, H?agen-Dazs ice cream, and Spider-Man movies have in common? The answer: Each is something that adults loved as children and that was reproduced in an expensive form for grown-ups. Asking brainstorming participants to ponder how their childhood passions could be recast as adult offerings might generate some fabulous ideas for new products or services.  相似文献   
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