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31.
HD 《电脑迷》2010,(18):29-29
在32nm制程Arrandale处理器的帮助下,Intel Calpella平台占据了主流笔记本市场大量份额,作为Intel老对手的AMD自然不会甘心放弃笔记本市场,于2010年第二季度推出针对主流笔记本市场的Danube(多瑙河)平台,凭借一贯以来在性价比上的良好口碑也让消费者对其抱有很大期待。今天,就借华硕K52Dr和海尔简爱7G两款笔记本产品的测试,让我们一同看看AMD Danube(多瑙河)和Intel Calpella两个平台在主流笔记本市场的表现……  相似文献   
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HD 《电脑迷》2010,(16):52-52
推开智能切换的大门 无需用户手动设置和等待即可在后台完成显卡切换动作,且不会对用户产生任何干扰,从而解决传统笔记本双显切换所要面对的屏幕闪烁、切换延迟、中断应用程序等问题,这样的优势让NVIDIA Optimus技术显得十分诱人。当然,笔记本想要支持NVIDIA Optimus技术是需要满足一定条件的,具体可参见下表。  相似文献   
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Motivated by the finding that the amino acid sequence of the Bence Jones protein BJP-DIA was identical to that of the main protein component of the amyloid fibrils obtained from the same patient with AL-amyloidosis, (Klafki, H.-W., Kratzin, H.-D., Pick, A.-I., Eckart, K., Karas, M. & Hilschmann, N. (1992) Biochemistry 31, 3265-3272.), we attempted to create "amyloid-like" fibrils from the Bence Jones protein in vitro, without addition of proteolytic enzymes. Reduction of BJP-DIA, solubilized in PBS, pH 7.4, overnight at 37 degrees C resulted in the formation of a precipitate which had affinity for the dye Congo red. Electron microscopy of negatively stained samples of the reduced protein revealed aggregates of linear unbranched fibrils. SDS-polyacrylamide gel electrophoresis demonstrated that the precipitate consisted almost exclusively of intact light chain molecules. This result makes it possible to deduce a molecular model of these amyloid fibrils generated in vitro.  相似文献   
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Forty-four patients suffering from acute and chronic schizophrenic psychoses were used to obtain, by using Lorr's scale (IMPS) and taking the changes in disease state observed within three months as a base, suggestions or pointers as to the proper treatment of disease with fluphenazine (lyorodin) which is a neuroleptically highly potent phenothiazine derivative. Megalomania, grandiose delusions apathetic and depressive syndromes showed marked tendencies toward major improvement. An "antiautistic" effect was observed in chronic patients. The effective dose was between 6 and 12 mg a day. The drug was well tolerated. In the majority of cases it was also necessary for antiparkinsonian drugs to be administered to patients. After twelve months of treatment, slight to major improvements or even freedom from symptoms could be observed in 28 cases (or 64%).  相似文献   
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HD 《电脑迷》2014,(12):25-25
正随着时代的发展,人们记录声音的方式有了巨大的变化。以MP3为代表的数码音频格式成为了现阶段主流的音频存储方式,这种保存方式让我们获取声音的方法越来越简便,但是这种经过转化、压缩和格式变化的保存方式让音频产生一定的失真。因此,喜爱音乐的人们开始寻找一种新的音乐保存方式与播放载体,纯音便携HiF i播放器就此让大众熟悉。  相似文献   
36.
The mechanism of binding of myosin subfragment-1 (S1) to actin in the absence of nucleotides was studied by a combination of stopped-flow fluorescence and ms time resolution electron microscopy. The fluorescence data were obtained by using pyrene-labeled actin and exhibit a lag phase. This demonstrates the presence of a transient intermediate after the collision complex and before the formation of the stable "rigor" complex. The transient intermediate predominates 2-15 ms after mixing, whereas the rigor complex predominates at time >50 ms. Electron microscopy of acto-S1 frozen 10 ms after mixing revealed disordered binding. Acto-S1 frozen at 50 ms or longer showed the "arrowhead" appearance characteristic of rigor. The most likely explanation of the disorder of the transient intermediate is that the binding is through one or more flexible loops on the surfaces of the proteins. The transition from disordered to ordered binding is likely to be part of the force-generating step in muscle.  相似文献   
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Agonistic and antagonistic properties of LPS and partial structures in the induction of cytokines are reviewed. Studies on structure-activity relationships of LPS and lipid A with human mononuclear cells reveal that S- and notably R-form LPS are very potent cytokine inducers. Synthetic E. coli lipid A is somewhat less active, whereas synthetic S. minnesota-type lipid A is significantly less active. Pentaacylated forms of lipid A are less potent than hexaacylated forms, and tetraacylated synthetic precursor Ia and bisacylated disaccharides and monosaccharides are completely inactive, indicating that a structure-dependent hierarchy of LPS and lipid A partial structures determines the monokine-inducing capacity in human mononuclear cells. Precursor Ia is a potent LPS antagonist. The mechanism of its inhibitory activity is shown to be due to competitive binding to cellular binding sites (receptors). Proinflammatory and antiinflammatory cytokines, receptor antagonists, and soluble cytokine receptors influence the cytokine-inducing activity of LPS, suggesting a complex regulatory network.  相似文献   
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