首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   17篇
  免费   1篇
化学工业   3篇
能源动力   1篇
轻工业   5篇
无线电   1篇
一般工业技术   2篇
冶金工业   6篇
  2021年   1篇
  2018年   1篇
  2016年   1篇
  2013年   2篇
  2010年   1篇
  2009年   1篇
  2008年   1篇
  2007年   1篇
  2004年   1篇
  2003年   1篇
  2001年   1篇
  1997年   2篇
  1996年   1篇
  1993年   2篇
  1989年   1篇
排序方式: 共有18条查询结果,搜索用时 734 毫秒
1.
2.
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   
3.
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   
4.
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   
5.
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   
6.
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   
7.
8.
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   
9.
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.
Infection with viruses, such as the lactate dehydrogenase-elevating virus (LDV), is known to trigger the onset of autoimmune anemia through the enhancement of the phagocytosis of autoantibody-opsonized erythrocytes by activated macrophages. Type I interferon receptor-deficient mice show enhanced anemia, which suggests a protective effect of these cytokines, partly through the control of type II interferon production. The development of anemia requires the expression of Fcγ receptors (FcγR) I, III, and IV. Whereas LDV infection decreases FcγR III expression, it enhances FcγR I and IV expression in wild-type animals. The LDV-associated increase in the expression of FcγR I and IV is largely reduced in type I interferon receptor-deficient mice, through both type II interferon-dependent and -independent mechanisms. Thus, the regulation of the expression of FcγR I and IV, but not III, by interferons may partly explain the exacerbating effect of LDV infection on anemia that results from the enhanced phagocytosis of IgG autoantibody-opsonized erythrocytes.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号