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451.
Interferon-gamma has been shown to be important for the resolution of inflammation associated with CNS autoimmunity. Because one of the roles of gamma delta T cells is the regulation of inflammation, we asked whether gamma delta T cells were able to regulate CNS inflammation using the autoimmune disease mouse model experimental autoimmune encephalomyelitis (EAE). We show that the presence of gamma delta T cells was needed to promote the production of IFN-gamma by both CD4 and CD8 T cells in the CNS before the onset of EAE. This regulation was shown to be independent of the ability of gamma delta T cells to produce IFN-gamma, and was specific to T cells in the CNS, as no alterations in IFN-gamma production were detectable in gamma delta T cell-deficient mice in the spleen and lymph nodes of mice with EAE or following immunization. Analysis of TCR gamma delta gene usage in the CNS showed that the only TCR delta V gene families present in the CNS before EAE onset are from the DV7s6 and DV105s1 gene families. We also show that the primary IFN-gamma-producing cells in the CNS are the encephalitogenic T cells, and that gamma delta T cell-deficient mice are unable to resolve EAE disease symptoms like control mice, thus exhibiting a long-term chronic disease course similar to that observed in IFN-gamma-deficient mice. These data suggest that CNS resident gamma delta T cells promote the production of IFN-gamma by encephalitogenic T cells in the CNS, which is ultimately required for the recovery from EAE.  相似文献   
452.
D-optimal design and Projection to Latent Structures (PLS) analysis were used to optimize screening hit 5 (B. subtilis AcpS IC(50): 15 microM, B. subtilis MIC: >200 microM) into a series of 4H-oxazol-5-one, small molecule, antibacterial, AcpS inhibitors. Specifically, 15, 16 and 18 show microM or sub-microM AcpS inhibition (IC(50)s: 15: 1.1 microM, 16: 1.5 microM, 18: 0.27 microM) and moderate antibacterial activity (MICs: 12.5-50 microM) against B. subtilis, E. faecalis ATCC, E. faecalis VRE and S. pneumo+.  相似文献   
453.
The lipid peroxidation (LPO) level between in the adult and old rats brain and liver was determined as to be essentially undiffering. Stress activated the LPO independence the age of animals and tissues investigated. The concentration changes of LPO products testify to it. In the adult rats under the stress capability of tissues to induction in vitro ferment and ascorbat-depending LPO, in comparison with the control, decreases, at old--does not change in the brain and considerably grows in the liver. Stress is accompanied by an oppression of Na, K-ATP-ase PM activity of hepatocytes, more expressed in the old animals.  相似文献   
454.
Tourova  T. P.  Kuznetzov  B. B.  Novikova  E. V.  Poltaraus  A. B.  Nazina  T. N. 《Microbiology》2001,70(6):678-684
Two copies of the 16S rRNA gene, rrnAand rrnB, of the type strain 17Tof the thermophilic sulfate-reducing bacterium Desulfotomaculum kuznetsoviiwere cloned and completely sequenced. The comparison of the determined sequences revealed considerable heterogeneity (8.3%) of the two genes, rrnAand rrnB.The main differences were associated with superlong inserts located in the variable 5"- and 3"-terminal regions of the 16S rRNA genes. Comparative analysis that involved analogous genes from the phylogenetically closest representatives of the genus Desulfotomaculumshowed that disregard of the heterogeneity of the two gene copies distorts the position of the bacterium studied in the phylogenetic tree.  相似文献   
455.
Nitrogen-fixing nodules from 16 species in 6 tribes of the sub-family Papilionaceae have been examined by scanning electron microscopy. The structure of infection threads was similar in all the studied papilionoid species except Lupinus polyphillus. In this species the infection threads were found in young nodules only. The morphology of bacterioids and the character of their "package" are determined by the host plant genotype. The obtained results are discussed in relation to the evolution of the legumes.  相似文献   
456.
Initial conditions for the thermoluminescence theory described in the first part of the present work were determined. The initial populations of possible states of the photosystem II reaction center and thermoluminescence of higher plants for different excitation conditions were estimated. The estimation enables one to explain the known experimental conditions favoring the appearance of certain thermoluminescence peaks. The possibility of applying the theory to the deconvolution of experimental curves into components was shown.  相似文献   
457.
Carboxypeptidase Z (CPZ) is a newly reported member of the metallocarboxypeptidase gene family, but unlike other members of this family, CPZ contains an N-terminal domain that has amino acid sequence similarity to Wnt-binding proteins. In order to gain insights as to the potential function of CPZ, the intracellular localization of this protein was determined in cell culture and in human tissues. When expressed in the AtT-20 mouse pituitary cell line, CPZ protein is routed to the regulated secretory pathway and secreted upon stimulation. A fraction of the secreted CPZ remains associated with the extracellular matrix. Endogenous CPZ in the PC12 rat pheochromocytoma cell line is also associated with the extracellular matrix. In human placenta, CPZ is present within invasive trophoblasts and in the surrounding extracellular space, indicating an association with extracellular matrix. CPZ is also present in amnion cells, but is not readily apparent in the extracellular matrix of this cell type. A human adenocarcinoma of the colon shows expression of CPZ in the extracellular matrix adjacent to malignant cells. Taken together, CPZ appears to be a component of the extracellular matrix in some cell types, where it may function in the binding of Wnt.  相似文献   
458.
Variations of the brain cortex redox state potential (E) were recorded in freely moving white rats (mass of 300-350 g) with implanted platinum electrodes (with the platinum reference electrode in the nasal bone) during sleep-wake cycles. It was found that transitions from the slow-wave sleep to wakefulness were accompanied in the number of cortical areas (metabolic-active sites) by the E rise, while the transitions from the wakefulness to slow-ware sleep were associated with a drop of E. However, the episodes of the short-term arousals during the slow-wave sleep were accompanied by the respective decreases in E thus forming the irregular E variations (1.5-3 min in duration). It was also found that the oscillations of a typical pattern (quasisinusoidal with the frequency of 10-20 osc/min and the amplitudes up to several mV) could take place in the metabolic-active cortical sites. These oscillations were defined as fast E oscillations. During the slow-wave sleep, the less regular oscillations with the lower frequency (1.2-10 osc/min) and higher amplitude were recorded in the same cortical sites. These oscillations were defined as slow. It is suggested that the fast metabolic oscillations of wakefulness are mainly controlled by the mitochondria of neuronal populations, whereas the slow metabolic oscillations which occur in the slow-wave sleep are related with glycolysis in populations of glial cells.  相似文献   
459.
We present a female child with mild mental retardation and congenital malformations. After fluorescence in situ hybridization (FISH) we found only abnormal karyotype in all cells. We used rapid FISH and original DNA probes--PAC62.10.1 and PAC20.19.N, specific for segments of chromosome 16q24. Karyotype of proband 46,XX.ish del(16)(q24.2:) (PAC20.19.N,PAC62.10.1-). Parent karyotypes are normal. This case may suggest the presence of clinical picture 16q- with defined clinical polymorphism at small telomeric loss, and also its necessary of the use of molecular-cytogenetic techniques in genetic departments.  相似文献   
460.
Yersinia pseudotuberculosis outer membrane (OM) recombinant mutant OmpF porins with deletions of the external loops L1, L6 and L8 were obtained using site-directed mutagenesis of the recombinant plasmid including ompF gene. Heterologeous expression of the mutant proteins was carried out in strain Rosetta of Escherichia coli (Novagen, USA), porins with the deletions were isolated from the inclusion bodies. Oligomers of mutant porins were obtained as result of dialysis and ion-exchange chromatography. Spatial structure of the mutant proteins was found to have special features in comparison with that of the full-structured OmpF porin on the level of both secondary and tertiary structure. As shown using bilayer lipid membrane (BLM) technique the absence of the loops L1, L6 and L8 didn’t affect the conductivity level of Y. pseudotuberculosis porin channel. The absence of the loops mentioned above has a significant influence on the antigenic structure of the mutant porins as demonstrated using immunoblotting technique and ELISA.  相似文献   
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