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排序方式: 共有128条查询结果,搜索用时 31 毫秒
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32.
Pilar del Hoyo Alberto García-Redondo Fernando de Bustos José Antonio Molina Youssef Sayed Hortensia Alonso-Navarro Luis Caballero Joaquín Arenas José AG Agúndez Félix Javier Jiménez-Jiménez 《BMC neurology》2010,10(1):95
Background
In the substantia nigra of Parkinson's disease (PD) patients, increased lipid peroxidation, decreased activities of the mitochondrial complex I of the respiratory chain, catalase and glutathione-peroxidase, and decreased levels of reduced glutathione have been reported. These observations suggest that oxidative stress and mitochondrial dysfunction play a role in the neurodegeneration in PD. We assessed enzymatic activities of respiratory chain and other enzymes involved in oxidative processes in skin fibroblasts cultures of patients with PD. 相似文献33.
HIV-particles in spermatozoa of patients with AIDS and their transfer into the oocyte 总被引:11,自引:1,他引:10 下载免费PDF全文
B Baccetti A Benedetto AG Burrini G Collodel EC Ceccarini N Crisa A Di Caro M Estenoz AR Garbuglia A Massacesi P Piomboni T Renieri D Solazzo 《The Journal of cell biology》1994,127(4):903-914
By immunocytochemistry and in situ hybridization at the electron microscopy level, and by the PCR technique, we have shown that HIV-1 binds and enters normal sperm; that viral particles, their antigens, and nucleic acid are present in sperm from HIV-1 infected men; and that such sperm can transfer HIV-1 like particles to normal human oocytes. We also present evidence that a galactosylceramide-like compound is present on the sperm membrane and could function as an alternative receptor for HIV. 相似文献
34.
Prospects for estimating nucleotide divergence with RAPDs 总被引:11,自引:0,他引:11
The technique of random amplification of polymorphic DNA (RAPD), which is
simply polymerase chain reaction (PCR) amplification of genomic DNA by a
single short oligonucleotide primer, produces complex patterns of anonymous
polymorphic DNA fragments. The information provided by these banding
patterns has proved to be of great utility for mapping and for verification
of identity of bacterial strains. Here we consider whether the degree of
similarity of the banding patterns can be used to estimate nucleotide
diversity and nucleotide divergence. With haploid data, fragments generated
by RAPD-PCR can be treated in a fashion very similar to that for
restriction-fragment data. Amplification of diploid samples, on the other
hand, requires consideration of the fact that presence of a band is
dominant to absence of the band. After describing a method for estimating
nucleotide divergence on the basis of diploid samples, we summarize the
restrictions and criteria that must be met when RAPD data are used for
estimating population genetic parameters.
相似文献
35.
W. Graham McLean Can Pekiner Nicola A. Cullum Ian F. Casson 《Molecular neurobiology》1992,6(2-3):225-237
Axonal transport is known to be impaired in peripheral nerve of experimentally diabetic rats. As axonal transport is dependent
on the integrity of the neuronal cytoskeleton, we have studied the way in which rat brain and nerve cytoskeletal proteins
are altered in experimental diabetes. Rats were made diabetic by injection of streptozotocin (STZ). Up to six weeks later,
sciatic nerves, spinal cords, and brains were removed and used to prepare neurofilaments, microtubules, and a crude preparation
of cytoskeletal proteins. The extent of nonenzymatic glycation of brain microtubule proteins and peripheral nerve tubulin
was assessed by incubation with3H-sodium borohydride followed by separation on two-dimensional polyacrylamide gels and affinity chromatography of the separated
proteins. There was no difference in the nonenzymatic glycation of brain microtubule proteins from two-week diabetic and nondiabetic
rats. Nor was the assembly of microtubule proteins into microtubules affected by the diabetic state. On the other hand, there
was a significant increase in nonenzymatic glycation of sciatic nerve tubulin after 2 weeks of diabetes. We also identified
an altered electrophoretic mobility of brain actin from a cytoskeletal protein preparation from brain of 2 week and 6 week
diabetic rats. An additional novel polypeptide was demonstrated with a slightly more acidic isoelectric point than actin that
could be immunostained with anti-actin antibodies. The same polypeptide could be produced by incubation of purified actin
with glucose in vitro, thus identifying it as a product of nonenzymatic glycation. These results are discussed in relation
to data from a clinical study of diabetic patients in which we identified increased glycation of platelet actin. STZ-diabetes
also led to an increase in the phosphorylation of spinal cord neurofilament proteins in vivo during 6 weeks of diabetes. This
hyperphosphorylation along with a reduced activity of a neurofilament-associated protein kinase led to a reduced incorporation
of32P into purified neurofilament proteins when they were incubated with32P-ATP in vitro. Our combined data show a number of posttranslation modifications of neuronal cytoskeletal proteins that may
contribute to the altered axonal transport and subsequent nerve dysfunction in experimental diabetes. 相似文献
36.
Genes and signalling in root development 总被引:12,自引:1,他引:11
37.
Bouhours-Nouet N May-Panloup P Coutant R de Casson FB Descamps P Douay O Reynier P Ritz P Malthièry Y Simard G 《American journal of physiology. Endocrinology and metabolism》2005,288(1):E171-E177
Maternal smoking during pregnancy is often associated with a decrease in placental function, which might lead to intrauterine growth retardation. Because tobacco is known to alter the mitochondrial respiratory function in cardiomyocytes and lung tissue, we hypothesized that placental mitochondrial function could be altered by maternal smoking. Placental mitochondria from 9 smoking and 19 nonsmoking mothers were isolated by differential centrifugation. Mitochondrial oxygen consumption was measured by polarography, and the enzymatic activity of each complex of the electron transport chain was assessed by spectrophotometry. In addition, the relative content in mitochondrial DNA (mtDNA) was determined by real-time quantitative PCR in placentas from seven smoking and seven nonsmoking mothers. We observed a 29% reduction in the enzymatic activity of complex III in the placental mitochondria from smokers compared with nonsmokers (P = 0.03). The relative content of mtDNA (with respect to the beta-globin gene) was reduced by 37% in the placental tissue from smokers compared with nonsmokers (P < 0.02). Both the enzymatic activity of complex III and mtDNA content were inversely related with the daily consumption of cigarettes, and mtDNA content was correlated with cord blood insulin-like growth factor-binding protein-3 (r = 0.74, P < 0.01), a marker of fetal growth. These results show that maternal smoking is associated with placental mitochondrial dysfunction, which might contribute to restricted fetal growth by limiting energy availability in cells. 相似文献
38.
Laser capture microdissection for the analysis of gene expression during embryogenesis of Arabidopsis 总被引:10,自引:0,他引:10
Casson S Spencer M Walker K Lindsey K 《The Plant journal : for cell and molecular biology》2005,42(1):111-123
It is during embryogenesis that the body plan of the developing plant is established. Analysis of gene expression during embryogenesis has been limited due to the technical difficulty of accessing the developing embryo. Here we demonstrate that laser capture microdissection can be applied to the analysis of embryogenesis. We show how this technique can be used in concert with DNA microarray for the large-scale analysis of gene expression in apical and basal domains of the globular-stage and heart-stage embryo, respectively, when critical events of polarity, symmetry and biochemical differentiation are established. This high resolution spatial analysis shows that up to approximately 65% of the genome is expressed in the developing embryo, and that differential expression of a number of gene classes can be detected. We discuss the validity of this approach for the functional analysis of both published and previously uncharacterized essential genes. 相似文献
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