全文获取类型
收费全文 | 109篇 |
免费 | 0篇 |
专业分类
教育与普及 | 1篇 |
现状及发展 | 66篇 |
研究方法 | 10篇 |
综合类 | 32篇 |
出版年
2012年 | 1篇 |
2011年 | 2篇 |
2008年 | 1篇 |
2007年 | 2篇 |
2006年 | 3篇 |
2005年 | 1篇 |
2004年 | 2篇 |
2003年 | 4篇 |
2002年 | 2篇 |
2001年 | 3篇 |
2000年 | 1篇 |
1999年 | 4篇 |
1992年 | 1篇 |
1991年 | 2篇 |
1990年 | 1篇 |
1989年 | 1篇 |
1988年 | 1篇 |
1987年 | 2篇 |
1981年 | 2篇 |
1980年 | 2篇 |
1979年 | 1篇 |
1978年 | 7篇 |
1977年 | 9篇 |
1976年 | 4篇 |
1975年 | 8篇 |
1974年 | 6篇 |
1973年 | 6篇 |
1972年 | 3篇 |
1971年 | 4篇 |
1970年 | 1篇 |
1969年 | 1篇 |
1968年 | 8篇 |
1967年 | 2篇 |
1966年 | 1篇 |
1965年 | 3篇 |
1962年 | 1篇 |
1959年 | 1篇 |
1956年 | 1篇 |
1955年 | 3篇 |
1954年 | 1篇 |
排序方式: 共有109条查询结果,搜索用时 31 毫秒
51.
52.
Extracts prepared from the mesodermal tissue surrounding the brain stimulate the differentiation of morphologically undifferentiated neuroblasts, while the differentiation of more mature neuroblasts is influenced by brain extracts. 相似文献
53.
F Pichinoty J L Garcia M Mandel C Job M Durand 《Comptes rendus des séances de l'Académie des sciences. Série D, Sciences naturelles》1978,286(19):1403-1405
Ten bacteria of the genus Bacillus were isolated from pasteurized soils, in anaerobiosis and at 32 degrees C, on peptone broth containing 0.5% KNO2. They are Gram variable rods producing oval spores. They are oxidase positive and have catalase. They grow, in anaerobiosis, on NO-3, NO-2, N2O, and NO as respiratory electron acceptors. These compounds are reduced to N2. 相似文献
54.
Origin of urinary methylated purines 总被引:4,自引:0,他引:4
55.
Summary Several branched fatty acids including an antiepileptic agent nDPA were tested as potential inhibitors of high affinity uptake of GABA by brain slices and synaptosomes. Only three compounds (2-butyl-3-propylhexanoic acid, 5-propyloctanoic acid, 2-propylpenten-2-oic acid) were found to be relatively weak inhibitors of the uptake system. There was no correlation between anticonvulsant properties of the branched fatty acids and their potencies as inhibitors of high affinity uptake of GABA. 相似文献
56.
C Cash M Maitre P Mandel 《Comptes rendus des séances de l'Académie des sciences. Série D, Sciences naturelles》1978,286(24):1829-1832
Two succinic semi-aldehyde reductases (A and B) have been purified to electrophoretic homogeneity. Enzyme A, which is a monomer of molecular weight 40,000 +/- 5,000 reduces a wide range of aldehydes and is inhibited by some barbiturates and certain anticonvulsants. Enzyme B, which is a dimer of molecular weight 80,000 +/- 10,000, is very specific for succinic semi-aldehyde and is not inhibited by the aforementioned compounds. 相似文献
57.
Quantum phase transition from a superfluid to a Mott insulator in a gas of ultracold atoms. 总被引:12,自引:0,他引:12
Markus Greiner Olaf Mandel Tilman Esslinger Theodor W H?nsch Immanuel Bloch 《Nature》2002,415(6867):39-44
For a system at a temperature of absolute zero, all thermal fluctuations are frozen out, while quantum fluctuations prevail. These microscopic quantum fluctuations can induce a macroscopic phase transition in the ground state of a many-body system when the relative strength of two competing energy terms is varied across a critical value. Here we observe such a quantum phase transition in a Bose-Einstein condensate with repulsive interactions, held in a three-dimensional optical lattice potential. As the potential depth of the lattice is increased, a transition is observed from a superfluid to a Mott insulator phase. In the superfluid phase, each atom is spread out over the entire lattice, with long-range phase coherence. But in the insulating phase, exact numbers of atoms are localized at individual lattice sites, with no phase coherence across the lattice; this phase is characterized by a gap in the excitation spectrum. We can induce reversible changes between the two ground states of the system. 相似文献
58.
Dystrophin. The gene and its product 总被引:11,自引:0,他引:11
J L Mandel 《Nature》1989,339(6226):584-586
59.
The deoxyguanosine kinase gene is mutated in individuals with depleted hepatocerebral mitochondrial DNA. 总被引:19,自引:0,他引:19
H Mandel R Szargel V Labay O Elpeleg A Saada A Shalata Y Anbinder D Berkowitz C Hartman M Barak S Eriksson N Cohen 《Nature genetics》2001,29(3):337-341
Mitochondrial DNA (mtDNA)-depletion syndromes (MDS; OMIM 251880) are phenotypically heterogeneous, autosomal-recessive disorders characterized by tissue-specific reduction in mtDNA copy number. Affected individuals with the hepatocerebral form of MDS have early progressive liver failure and neurological abnormalities, hypoglycemia and increased lactate in body fluids. Affected tissues show both decreased activity of the mtDNA-encoded respiratory chain complexes (I, III, IV, V) and mtDNA depletion. We used homozygosity mapping in three kindreds of Druze origin to map the gene causing hepatocerebral MDS to a region of 6.1 cM on chromosome 2p13, between markers D2S291 and D2S2116. This interval encompasses the gene (DGUOK) encoding the mitochondrial deoxyguanosine kinase (dGK). We identified a single-nucleotide deletion (204delA) within the coding region of DGUOK that segregates with the disease in the three kindreds studied. Western-blot analysis did not detect dGK protein in the liver of affected individuals. The main supply of deoxyribonucleotides (dNTPs) for mtDNA synthesis comes from the salvage pathway initiated by dGK and thymidine kinase-2 (TK2). The association of mtDNA depletion with mutated DGUOK suggests that the salvage-pathway enzymes are involved in the maintenance of balanced mitochondrial dNTP pools. 相似文献
60.