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Leber hereditary optic neuropathy (LHON) is a maternally inherited disorder, associated with mutations in the mitochondrial DNA, which is notorious for its aspecific presentations. Two pedigrees are described with cases that are atypical for LHON with respect to sex, age of onset, interval between the eyes becoming affected, course of the disease, concomitant disorders, additional test results, final visual acuity, and/or results of mtDNA analysis. Moreover, the pedigrees themselves did not suggest maternal inheritance. We analysed the diagnostic and clinical genetic difficulties related to the atypical aspects of these pedigrees. We conclude that mtDNA analysis is justified in every case of optic nerve atrophy with no clear cause. Identification of one of the three LHON specifically associated mtDNA mutations is essential to confirm the diagnosis.  相似文献   
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Fourteen cases of alveolar echinococcosis were examined by computed tomographic (CT) scanning of the liver, including 3 cases before treatment and 11 cases 2.0-7.5 years after long-term continuous albendazole therapy. In 7 cases the hepatic lesions were almost completely calcified and cured, while in 3 cases incomplete calcification of the peripheral margin of the hepatic lesions was observed. CT scanning of the one uncured case and the 3 cases before treatment showed active lesions with heterogeneous hypodense areas in the liver without calcification on the peripheral margin. Long-term continuous albendazole therapy can result in parasitological cure with death of the parasite.  相似文献   
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Meat quality traits have low heritability and large environmental influences. To predict, improve and manage meat quality, proteomic biomarkers are superior to genetic markers. The objectives of this research were (1) to find associations between proteome profiles of longissimus muscle at slaughter and meat quality accuracies of prediction of traits ranged from 20 up to 80%. Differentially expressed proteins related to drip loss and ultimate pH were identified by NanoLC-FTMSMS. The proteins highlight biological mechanisms that may explain how these traits develop biologically and how they are related to each other.  相似文献   
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To change the driving behavior of mail-van drivers so as to encourage energy saving, a program was developed and implemented in the Netherlands Postal and Telecommunications Services (PTT). Based on empirical analysis, 3 approaches were used to influence driving behavior: providing information, providing task assignment and control, and providing feedback on gasoline consumption. The effectiveness of the program was tested in a field experiment. Attitudes, social norms, and reported behavior changed, and energy savings of more than 7% were achieved, compared with a control group. From an economic point of view, further implementation in the PTT organization could be attractive. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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In small cell lung cancer (SCLC), bone marrow metastases are frequently detected by bone scintigraphy (BS) and/or unilateral bone marrow biopsy and aspiration (BMBA). In this study, the value of magnetic resonance imaging (MRI) of thoracic spine and pelvis was compared with BS and BMBA and its clinical implication was evaluated in 42 patients with SCLC. Patients were staged (including BS, BMBA, CT thorax, Liver ECHO) as limited (LD) or extensive disease (ED) before and after MRI. MRI was positive in 12 BS negative (P = 0.003) and in 14 BMBA negative patients (P < 0.001), while in 8 patients, MRI was the only sign of ED, which resulted in a decrease of patients categorised with LD from 52 to 33%. However, in this small group of LD patients, there was no significant survival difference between LD (MRI pos) and LD (MRI neg) patients. It is concluded that MRI can be of value in the staging of LD patients, but it has no influence on survival.  相似文献   
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Electricity power systems worldwide have traditionally been designed to a vertically connected scheme characterised by centralised generation. Over the last few decades, several factors have dictated a gradual shift from the central‐control approach to a more distributed layout where distributed generation (DG) technologies are effectively integrated and not just connected (appended) to the networks; amongst others liberalisation of electricity markets, security and quality of supply and environmental issues. Photovoltaic powered distributed generation (PV‐DG), although still having a much lesser impact than other DG technologies, is increasingly being embedded into electricity distribution networks worldwide within the framework of successful regulatory state and marketing programmes. PV‐DG has added values (benefits) for the electricity systems that extend from peak power and load reduction (when deployed close to electricity consumption points) to participation in grid‐supporting or grid‐forming modes of operation. The question arises as to what the present situation of PV technology is for its optimal integration in distribution networks, whether there are still technical barriers to overcome as well as new opportunities for PV in future renewably supplied electricity systems. This paper presents the current state of knowledge concerning these topics from a European perspective with regard to different grid structures. It also discusses existing standards, new opportunities to provide grid services and research and development needs identified to fully exploit the added‐value—and still developing—benefits of PV‐DG. Copyright © 2008 John Wiley & Sons, Ltd.  相似文献   
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An on-line in vitro perfusion technique is described that allows the continuous quantification of cellular glucose metabolism in vitro. Using biosensor technology, we measure glucose and lactate metabolism at a minute-to-minute time resolution for periods up to several days. The application of our perfusion-detection technique for in vitro monitoring is demonstrated in a wide variety of cells, including primary neuronal and astroglia cultures, yeast cells, and human lymphocytes. The method shows that variations in oxygen delivery or exposure to a noncompetitive pseudosubstrate (here 2-deoxyglucose) affects normal glucose metabolism. The innovative advantage of the present system is that, in contrast to other devices including a recently described system, metabolism per cell can be quantified. The potential of in vitro on-line monitoring is discussed for application in studying normal and abnormal metabolism, toxic and nontoxic drug effects, and human tissue biopsies.  相似文献   
10.
The leaf methanol extract of Syringa oblata Lindl var. alba was investigated as a source of oleuropein and related compounds. The extract had a high total phenol content and a radical scavenging activity similar to that of the respective extract from Olea europaea leaves. HPLC‐DAD characterisation of the two most abundant phenolic compounds in the extract of S. oblata indicated that both had UV spectra matching that of oleuropein. The presence of oleuropein was verified by using LC‐MS. Identification of the second compound was only feasible after isolation (preparative HPLC) and spectroscopic characterisation [LC‐MS, 1H NMR and homonuclear two‐dimensional correlated spectroscopy (COSY)]. The compound identified was the known bioactive syringopicroside. On the basis of MS data other peaks were assigned to oleuropein aglycone, verbascoside, ligstroside and syringopicroside derivatives, as well as to a luteolin rutinoside. The findings are promising for the potential exploitation of S. oblata leaf extract as a source for oleuropein and other bioactive ingredients. Copyright © 2006 Society of Chemical Industry  相似文献   
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