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A widespread proteomics procedure for characterizing a complex mixture of proteins combines tandem mass spectrometry and database search software to yield mass spectra with identified peptide sequences. The same peptides are often detected in multiple experiments, and once they have been identified, the respective spectra can be used for future identifications. We present a method for collecting previously identified tandem mass spectra into a reference library that is used to identify new spectra. Query spectra are compared to references in the library to find the ones that are most similar. A dot product metric is used to measure the degree of similarity. With our largest library, the search of a query set finds 91% of the spectrum identifications and 93.7% of the protein identifications that could be made with a SEQUEST database search. A second experiment demonstrates that queries acquired on an LCQ ion trap mass spectrometer can be identified with a library of references acquired on an LTQ ion trap mass spectrometer. The dot product similarity score provides good separation of correct and incorrect identifications. 相似文献
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Fernando Ruiz 《微电脑世界》2012,(11):128-130
随着Android终端设备的快速普及,这个移动互联的大时代,不仅促成了智能设备的如日中天,同时也为罪恶之手打开了一扇全新的大门。Android.FakeInstaller就是这样一个广泛传播的移动恶意软件系列。它曾假冒奥运会赛事成绩应用、Skype、Flash Player、Opera和许多其他流行应用程序。事实上,在移动恶意软件界,FakeInstaller系列是我 相似文献
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Interphase nuclei are organized into structural and functional domains. The coiled body, a nuclear organelle of unknown function, exhibits cell type-specific changes in number and morphology. Its association with nucleoli and with small nuclear ribonucleo-proteins (snRNPs) indicates that it functions in RNA processing. In cycling cells, coiled bodies are round structures not associated with nucleoli. In contrast, in neurons, they frequently present as nucleolar "caps." To test the hypothesis that neuronal differentiation is accompanied by changes in the spatial association of coiled bodies with nucleoli and in their morphology, PC12 cells were differentiated into a neuronal phenotype with nerve growth factor (NGF) and coiled bodies detected by immunocytochemical localization of p80-coilin and snRNPs. The fraction of cells that showed coiled bodies as nucleolar caps increased from 1.6 +/- 0.9% (mean +/- SEM) in controls to 16.5 +/- 1.6% in NGF-differentiated cultures. The fraction of cells with ring-like coiled bodies increased from 17.2 +/- 5.0% in controls to 57.8 +/- 4.4% in differentiated cells. This was accompanied by a decrease, from 81.2 +/- 5.7% to 25.7 +/- 3.1%, in the fraction of cells with small, round coiled bodies. SnRNPs remained associated with typical coiled bodies and with ring-like coiled bodies during NGF-induced recruitment of snRNPs to the nuclear periphery. Together with the observation that coiled bodies are also present as nucleolar caps in sensory neurons, the results indicate that coiled bodies alter their morphology and increase their association with nucleoli during NGF-induced neuronal differentiation. 相似文献
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Lutz Wolfgang; Leach Chris; Barkham Michael; Lucock Mike; Stiles William B.; Evans Chris; Noble Rachael; Iveson Steve 《Canadian Metallurgical Quarterly》2005,73(5):904
This study extended client-focused research by using the nearest neighbor (NN) approach, a client-specific sampling and prediction strategy derived from research on alpine avalanches. Psychotherapy clients (N = 203) seen in routine practice settings in the United Kingdom completed a battery of intake measures and then completed symptom intensity ratings before each session. Forecasts of each client's rate of change and session-by-session variability were computed on the basis of that client's NNs (n = 10-50 in different comparisons). Alternative forecasts used linear or log-linear slopes and were compared with an alternative prediction strategy. Results showed that the NN approach was superior to the alternative model in predicting rate of change, though the advantage was less clear for predicting variability. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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HF Chambers T Kocag?z T Sipit J Turner PC Hopewell 《Canadian Metallurgical Quarterly》1998,26(4):874-877
Some beta-lactam antibiotics are active in vitro against Mycobacterium tuberculosis. There are anecdotal reports of successful treatment of tuberculosis caused by multiple-drug-resistant strains of M. tuberculosis with regimens that included amoxicillin/clavulanate. Reduction of M. tuberculosis in the sputum of patients with pulmonary tuberculosis during administration of amoxicillin/clavulanate was measured by a quantitative culture method to determine the activity in vivo. Patients were randomized to receive isoniazid, ofloxacin, or amoxicillin/clavulanate for 7 days. Isoniazid was the most effective agent, reducing M. tuberculosis after 2 days at a mean rate (+/- standard deviation) of 0.60 +/- 0.30 log10 cfu/mL per day, compared with 0.32 +/- 0.05 and 0.34 +/- 0.03 for ofloxacin and amoxicillin/clavulanate, respectively. The early bactericidal activity of amoxicillin/clavulanate was comparable to that reported for antituberculous agents other than isoniazid. Further studies of beta-lactam antibiotics with in vitro activity against M. tuberculosis are warranted to define their role in treatment of tuberculosis. 相似文献
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