全文获取类型
收费全文 | 63篇 |
免费 | 7篇 |
出版年
2019年 | 1篇 |
2016年 | 3篇 |
2015年 | 3篇 |
2014年 | 4篇 |
2013年 | 1篇 |
2012年 | 8篇 |
2011年 | 5篇 |
2010年 | 3篇 |
2009年 | 1篇 |
2008年 | 1篇 |
2006年 | 1篇 |
2005年 | 2篇 |
2004年 | 2篇 |
2003年 | 2篇 |
2001年 | 1篇 |
2000年 | 1篇 |
1999年 | 1篇 |
1998年 | 1篇 |
1996年 | 1篇 |
1994年 | 3篇 |
1991年 | 2篇 |
1990年 | 1篇 |
1989年 | 1篇 |
1988年 | 2篇 |
1986年 | 3篇 |
1984年 | 1篇 |
1983年 | 1篇 |
1982年 | 1篇 |
1979年 | 1篇 |
1978年 | 2篇 |
1977年 | 1篇 |
1974年 | 3篇 |
1973年 | 1篇 |
1972年 | 1篇 |
1970年 | 1篇 |
1969年 | 1篇 |
1968年 | 1篇 |
1965年 | 1篇 |
排序方式: 共有70条查询结果,搜索用时 186 毫秒
1.
The mitochondrial content of long-chain acyl-CoA esters in the brown adipose tissue of guinea pigs increased 3.5-fold from a level of 92 +/- 17 pmol per mg protein (+/- S.E.; n = 7) in the control animals adapted at 22 degrees C to a new steady-state level of 328 +/- 20 pmol per mg protein (+/- S.E.; n = 46) after 10 days of cold-acclimation (5 degrees C). These low values of long-chain acyl-CoA species and the slow adaptive response for their increase do not support the proposal (Cannon, B., Sindin, U. and Romert, L. (1977) FEBS Lett. 4, 43-46) that the fatty acid CoA-esters have a physiological function in the regulation of the H+ (or OH-) permeability of the mitochondrial inner membrane. Experimental evidence is presented supporting the proposal that the long-chain acyl-CoA species are largely confined to the cytosolic side of the inner membrane. The activity of the adenine nucleotide translocase, as estimated at 25 degrees C in the reverse direction, was found to increase 5-fold upon depletion of the mitochondria of fatty acids (free and esterified) by preincubation with bovine serum albumin. The presence of potent inhibitors, i.e., long-chain acyl-CoA species, of adenine nucleotide translocation in brown adipose tissue of thermogenically active animals further supports the conclusion that ATP hydrolyzing mechanisms contribute insignificantly to long-term thermogenesis. The low values of long-chain acyl-CoA hydrolase (EC 3.1.2.1) activity, as measured in intact mitochondria and on a mitochondrial matrix fraction (i.e., 1.6 nmol X min-1 per mg protein), do not support the proposal that the hydrolase activity plays a significant role in the loose-coupling of brown adipose tissue mitochondria, either by a futile cycle mechanism or promoted by free fatty acid-induced uncoupling. 相似文献
2.
Summary Sections of neurosecretory cells fixed in glutaraldehyde and osmium tetroxide were studied by means of an EMMA-4 analytical microscope. Secretory granules in neurosecretory cells of the corpus cardiacum and of the brain, both in the desert locust Schistocerca and in the blowfly Calliphora, as well as neurosecretory granules in posterior pituitaries of the frog Rana and of the albino rat all contain a high concentration of calcium. A distinct sulphur peak was also a constant feature.In neurosecretory cells of the corpus cardiacum of Schistocerca the chromatin contained a high concentration of calcium. The mitochondria also contained much calcium, but part of this disappeared during preparation except when fixative and wash contained calcium chloride. By block staining with uranyl acetate most calcium is displaced from the mitochondria, whereas most of the calcium remains in the neurosecretory granules. Since the calcium peaks in spectra from neurosecretory granules appear of similar size, regardless of variations in the preparative procedure, this calcium must be firmly bound. The possible role of the calcium bound to the neurosecretory substance is discussed.The presence of sulphur in insect neurosecretory granules indicates the presence of a protein besides the hormone, i.e., an insect neurophysin.We wish to thank Dennis Greer for the operation of the analytical microscope. This work was supported by a Wellcome-Carlsberg Travelling Research Fellowship awarded to T.N. The EMMA-4 facility is supported by a grant from the British Science Research Council 相似文献
3.
Lill Sverresdatter Larsen Hans Ketil Normann Torunn Hamran 《Ethnic and racial studies》2016,39(5):821-839
The aim of this study was to explore how caregivers experience collaboration in rural municipalities in northern Norway. We conducted fieldwork with a dementia team in addition to seventeen qualitative in-depth interviews with formal and family caregivers. The caregivers had ethnic Sami and ethnic Norwegian affiliation. The theme ‘negotiating ethnic and ethno-political positions’ was identified through thematic analysis and developed using positioning theory. Ethnicity involves dynamic and situated personal affiliations, and participants negotiate each other's ethnic positions in practice. Negotiations of ethnic positions hamper collaboration between formal and family caregivers, and ethno-political positions reinforce stereotyped ethnic positions. This study contributes to the understanding of and the debate over positions on ethno-cultural collaboration in health care. In practice, participants negotiate the health policy concept of ‘cultural facilitation’, which must be broadened to ensure equal healthcare services. 相似文献
4.
Background
Patents are one of the most important forms of intellectual property. They grant a time-limited exclusivity on the use of an invention allowing the recuperation of research costs. The use of patents is fiercely debated for medical innovation and especially controversial for publicly funded research, where the patent holder is an institution accountable to public interest. Despite this controversy, for the situation in Germany almost no empirical information exists. The purpose of this study is to examine the amount, types and trends of patent applications for health products submitted by German public research organisations.Methods/Principal Findings
We conducted a systematic search for patent documents using the publicly accessible database search interface of the German Patent and Trademark Office. We defined keywords and search criteria and developed search patterns for the database request. We retrieved documents with application date between 1988 and 2006 and processed the collected data stepwise to compile the most relevant documents in patent families for further analysis. We developed a rationale and present individual steps of a systematic method to request and process patent data from a publicly accessible database. We retrieved and processed 10194 patent documents. Out of these, we identified 1772 relevant patent families, applied for by 193 different universities and non-university public research organisations. 827 (47%) of these patent families contained granted patents. The number of patent applications submitted by universities and university-affiliated institutions more than tripled since the introduction of legal reforms in 2002, constituting almost half of all patent applications and accounting for most of the post-reform increase. Patenting of most non-university public research organisations remained stable.Conclusions
We search, process and analyse patent applications from publicly accessible databases. Internationally mounting evidence questions the viability of policies to increase commercial exploitation of publicly funded research results. To evaluate the outcome of research policies a transparent evidence base for public debate is needed in Germany. 相似文献5.
6.
7.
8.
Felix Normann Patrick Weigelt Christine Gehrig-Downie S. Robbert Gradstein Harrie J.M. Sipman André Obregon Jörg Bendix 《Ecological Indicators》2010,10(6):1111-1118
Recent work on bryophyte diversity in lowland forests of northern South America has suggested the existence of a new type of cloud forest, the “tropical lowland cloud forest” (LCF). LCF occurs in river valleys with high air humidity and radiation fog, and is rich in epiphytes. We explored the lichenological characteristics of putative LCF in a lowland area (200–400 m a.s.l.) near Saül, central French Guiana, using macrolichens (including large crustose species) as indicator taxa. We analyzed macrolichen diversity on 16 trees in two 1 ha plots, in LCF and in lowland rain forest without fog (LRF). Sampling efficiency was ca. 80% in both forest types. Canopies of both LRF and LCF were richer in lichen species than understory trunks. Species richness of macrolichens was rather similar in the two forest types but species composition was significantly different. Cyanolichen richness in LCF was ca. 2.5 times higher than in LRF; in contrast, LRF had 4 times more species of green-algal Parmeliaceae. Our study suggests that cyanolichens except for Coccocarpiaceae serve as indicators of LCF. We explain the detected diversity patterns by differences in water availability due to fog precipitation and higher humidity. This is indicated by the higher relative air humidity in the lowland cloud forest, which was >6% higher than in the rain forest. 相似文献
9.
Population kinetic study of guinea pig monocytes and their subsets during acute inflammation 总被引:1,自引:0,他引:1
Guinea pig peripheral blood monocytes exist in four subsets which differ in cytochemistry, function, rates of production, and circulatory time during steady state. These subsets are designated small, intermediate, large, and very large vacuolated monocytes. To address the question as to whether all subsets participate equally in the acute inflammatory response, population kinetics were performed on monocyte subsets isolated by counterflow centrifugation elutriation following a single intravenous pulse of tritiated thymidine given concurrently with an intraperitoneal injection of phytohemagglutinin as phylogistic agent. Inflammation reduced the cell cycle times of the precursors for all monocyte subsets, increasing their production. However, inflammation increased the number of precursors only for large monocytes. In addition, a reserve of exclusively large monocytes existed which appeared in the circulation within 3 hr of inflammation induction. The subsequent loss of large monocytes from the circulation exceeded their production in contrast to all other monocyte fractions. Over 92% of all monocytes entering the acute inflammatory site were large monocytes despite the fact that they constituted only 58% of monocytes under steady state conditions. Small, intermediate, and very large vacuolated monocytes were only minor participants in the acute inflammatory response. These results indicate heterogeneity in the monocyte subset response to acute inflammation. 相似文献
10.
Paul M. Ridker Stefan N. Willich James E. Muller Charles H. Hennekens 《Chronobiology international》1991,8(5):327-335
The onset of several acute cardiovascular diseases occurs in a circadian pattern, with a peak incidence in the hours soon after awakening. This finding, coupled with laboratory data that confirm a surge in platelet activation during the early morning hours, suggests that acute changes in platelet aggregability may be an important trigger of thrombosis. Therefore, the efficacy of antiplatelet agents, such as aspirin, in reducing risks of vascular occlusion may result, at least in part, from a blunting of these short-term changes in platelet aggregability. In this review, clinical and laboratory evidence describing these cyclical changes is discussed, as is current evidence of the effects of aspirin on platelet function and the circadian variation of acute thrombosis. 相似文献