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101.
Fatty acid hydroperoxide lyase (HPO lyase) was found in green and non-green tobacco cells cultured in vitro. The HPO lyase activity in non-green cells was 13-12 of that in green cells. When the cells were transferred from the light to dark conditions or vice versa, cells turned non-green or green according to the light conditions. The HPO lyase activity also changed according to the light conditions, but the changes in HPO lyase activities were not proportional to the changes in chlorophyll contents. These results suggest that at least two types of HPO lyases are present in the green cells. One type of HPO lyase is perhaps common both to the green and non-green cells; another one is chloroplastic. The fatty acid compositions of cells and substrate specificities of HPO lyase differed between green and non-green cells.  相似文献   
102.
We describe subject recruitment and research results from the Osaka University Aged Twin Registry (OUATR). The research focus of OUATR is the genetic and environmental contributions to physical-cognitive-mental aging which we examined in Japanese twins in later adulthood. Within this large-scale registry (12,000 pairs) of oriental twins born between 1900 and 1935, approximately 10% of participants are MZ twins reared apart from early childhood. Two hundred and fifty pairs have had comprehensive medical examinations, including various blood chemical panels, lymphocyte subtests, WAIS (Wechsler Adult Intelligence Scale), and urine analysis. The future foci of this study are primarily on longevity, decline of cognitive functions with aging, bio-physiological functions, lifestyle and behavior genetics, and psycho-spiritual functions.  相似文献   
103.
Utsunomiya I  Ito M  Oh-ishi S 《Cytokine》1998,10(12):956-963
Levels of inflammatory cytokines tumour necrosis factor (TNF), interleukin 1 (IL-1), IL-6, and cytokine-induced neutrophil chemoattractant (CINC), which is a member of the alpha-chemokine family in rats, were measured in the pleural exudates during zymosan-induced pleurisy to examine the relationship between the local production of cytokines and the inflammatory reaction. All four cytokine levels in the pleural exudate began to increase after 1-2 h, preceding the influx of neutrophils, and peaked after 4-5 h. Thereafter, these cytokine levels declined after 24 h, whereas the exudate volume still continued to increase and leukocyte number reached a plateau. Concomitant injection of actinomycin D (10 microg) with zymosan markedly suppressed the neutrophil infiltration, parallel with CINC production in the pleural exudate at 4 h. A transient elevation of IL-6 level, peaking at 5 h, and subsequent rise in the level of an acute-phase protein, T-kininogen, were also observed in the plasma. When recombinant human TNF-alpha (rhTNF-alpha) (20 000 U) was intrapleurally injected a rapid increase in pleural CINC level, followed by neutrophil infiltration, and a sharp rise in IL-6 level in the plasma, followed by an increase in T-kininogen, were demonstrated. These results suggest that CINC produced in the pleural exudate may participate in neutrophil infiltration, that IL-6 induced in the plasma stimulates T-kininogen production, and that endogenous TNF may be partly involved in the induction of CINC and IL-6 in this zymosan inflammation.  相似文献   
104.
Tissue and cellular localization of NADH-dependent glutamate synthase (NADH-GOGAT, EC 1.4.1.14) in the unexpanced leaf blades and young grains of rice (Oryza sativa L.) was investigated using tissue-print immunoblot and immunocytological methods with an affinity-purified anti-NADH-GOGAT immunoglobulin G. Tissue-print immunoblots showed that the NADH-GOGAT protein was mostly located in large and small vascular bundles of the unexpanded blades. When the cross-sections (10μ in thickness) prepared from the paraffin-embedded blades were stained with the antibody, the NADH-GOGAT protein was detected in vascular-parenchyma cells and mestome-sheath cells. In developing grains, the NADH-GOGAT protein was detected in both phloem- and xylem-parenchyma cells of dorsal and lateral vascular bundles, and in the nucellar projection, nucellar epidermis, and aleurone cells. On the other hand, ferredoxin (Fd)-dependent GOGAT (EC 1.4.7.1) was located mainly in mesophyll cells of the leaf blade and in chloroplast-containing cross-cells of the pericarp of the grains. The spatial expression of these GOGAT proteins indicates distinct and non-overlapping roles in rice plants. In the leaf blades and young grains, NADH-GOGAT could be involved in the synthesis of glutamate from the glutamine that is transported through the vascular system from roots and senescing tissues.  相似文献   
105.
The isotopic fractionation of nitrogen in the reaction in vitroof glutamine synthetase isolated from spinach (Spinacia oleraceaL.) leaves was calculated from the changes in natural 15N abundance(  相似文献   
106.
In situ hybridization (ISH) at the electron microscopic level is essential for elucidating the intracellular distribution and role of mRNA in protein synthesis. We describe our electron microscopic ISH method using biotinylated oligonucleotide probes for rat growth hormone and prolactin mRNAs and compare the preembedding method with the postembedding method. Preembedding electron microscopic ISH localized rat growth hormone and prolactin mRNAs on the polysomes of the rough endoplasmic reticulum (RER). Rat growth hormone mRNA was distributed diffusely on the RER, whereas rat prolactin mRNA was scattered and distributed focally. Thus there might be a specific translational site for prolactin mRNA on the RER. Rat growth hormone mRNA signals were also recognized on the polysomes of the RER, using the postembedding method with streptavidin gold conjugate. The hybridization signal intensity using the postembedding method was lower, and non-specific signals were more frequent, in comparison with the preembedding method. The preembedding method thus appears to be easier and better than the postembedding method from the viewpoint of utility and preservation of mRNA. Electron microscopic ISH is considered to be an important tool for evaluating the intracellular localization of mRNA and the site of specific hormone synthesis on the RER.  相似文献   
107.
Summary Dual innervation of snake cerebral blood vessels by adrenergic and cholinergic fibres was demonstrated with the use of histochemical methods. Although the nerve plexuses are somewhat less dense, the essential features of innervation of the blood vessels are similar to those of mammals with the exception that the adrenergic plexuses are more prominent than the cholinergic plexuses. The major arteries of the cerebral carotid system have a rich nerve supply. However, the innervation is less rich in the basilar and poor in the spinal (vertebral) arteries. Although the arteries supplying the right side of head are poorly developed, three pairs of arteries, cerebral carotids, ophthalmics and spinals, supply the snake brain. The carotids and ophthalmics are densely innervated and are accompanied by thick nerve bundles, suggesting that the nerves preferentially enter the skull along those arteries. Some parenchymal arterioles are also dually innervated. Connection between the brain parenchyma and intracerebral capillaries via both cholinergic and adrenergic fibres was observed. In addition cholinergic nerve fibres, connecting capillaries and the intramedullary nerve fibre bundles, were noticed. Capillary blood flow may be influenced by both adrenergic and cholinergic central neurons. The walls of capillaries also exhibit heavy acetylcholinesterase activity. This may indicate an important role for the capillary in the regulation of intracerebral blood flow.  相似文献   
108.
Molecular Genetics and Genomics - We constructed transformants of B. subtilis 168 which acquired genes for site-specific restriction endonucleases. These endonucleases originated from various...  相似文献   
109.
Alcohol dehydrogenase (alcohol: NAD oxidoreductase, E.C. 1.1.1.1.) was purified from Thea sinensis seeds. Its M.W was 95000 and it was composed of two homogeneous subunits with MWs of 47000. The dissociation into subunits was caused by o-phenanthroline. Substrate specificity for monoterpene alcohols and aldehydes is discussed.  相似文献   
110.
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