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71.
The influence of lactobacilli and new probiotic product on mitochondrial energetics of rat heart mitochondria and on dynamics of intracellular calcium concentration ([Ca2+]i) of cardiomyocytes and rat aortic smooth muscle cells was investigated. Respiration of mitochondra was estimated polarographically. [Ca2+]i was measured using fluorescent calcium indicator Fura 2 AM and calcium imaging system. The application of lactobacilli (5 × 107 CFU/mL) was shown to increase [Ca2+]i in cardiomyocytes, thereby increasing myocardial contractility. On the other hand, application of lactobacilli reduced thapsigargin-induced calcium influx in smooth rat aortic muscle, thus exhibiting some hypotensive effect. It was shown that probiotic product stimulated mitochondria respiration and exerted a mild uncoupling effect on electronic transport and oxidative phosphorylation in mitochondria. In cardiomyocytes and in smooth muscles probiotic product increased [Ca2+]i and consequent increase in contractility of blood vessels and myocardium. It is supposed that the probiotic product can be effectively applied at the endotoxic shock, when contractility of blood vessels in response to vasoconstrictor agents is suppressed.  相似文献   
72.
The composition of fatty acids (FAs) of a green alga (Ulva intestinalis) inhabiting small rivers of the Elton Lake basin has been investigated. It has been established that long-chain FAs with 16 and 18 carbon atoms are essential. We have investigated the composition variability of FAs of lipids of U. intestinalis depending on environmental factors: the level of mineralization, temperature, oxygen saturation, and acidity. It has been revealed that FA nonsaturation increases with an increase in mineralization. We assume that ω-6 and ω-3 desaturases participate in the adaptation of U. intestinalis to this factor.  相似文献   
73.
We used maximum likelihood analysis of complete mitochondrial ND2 sequences (1041 bp) to clarify the taxonomy and relationships of various species and genera of grass and bush warblers. The tree revealed two clades of grass and bush warblers. One clade was comprised of all four western Palearctic Locustella and two species of Asian Bradypterus . The other clade included five eastern Palearctic Locustella (including the distinctive Sakhalin warbler Locustella amnicola ) and the marsh grassbird Megalurus pryeri . African Bradypterus and Australian little grassbird Megalurus gramineus were distantly related to their Asian congeners. Therefore, current taxonomy of these genera does not reflect their evolutionary history and needs revision. It is proposed that a phylogenetic analysis of morphology and ecological preferences would show that the current taxonomy of grass and bush warblers reflects species' habitat preferences and morphology related to locomotion and foraging in their habitats, rather than their shared ancestry. Distinct clades were found in grasshopper warbler Locustella naevia and Pallas's grasshopper warbler L. certhiola . Detailed phylogeographic studies are needed to elucidate the species status of the clades within these two species.  相似文献   
74.
Mitochondrial DNA and plumage evolution in the white wagtail Motacilla alba   总被引:1,自引:0,他引:1  
We analyzed sequences of two mitochondrial DNA (mtDNA) gene regions (control region and ND2) totaling 1477 base‐pairs from 232 specimens of the white wagtail Motacilla alba obtained from 27 localities throughout Eurasia. Although overall haplotype diversity was relatively low (0.79) and the most common haplotype was shared by 45% of individuals, belonging to six subspecies, a high level of population differentiation was detected. The mtDNA tree revealed three clades: (1) most individuals from Krasnodar (belonging to M. a. alba subspecies), (2) all individuals from Almaty and some from Primor'e (belonging to M. a. personata, M. a. lugens and M. a. leucopsis subspecies), and (3) the remaining individuals (representing all subspecies and all localities except Almaty). We suggest that these three clades represent historically isolated populations that relatively recently came into secondary contact in Krasnodar and Primor'e. None of the six subspecies were reciprocally monophyletic in the mtDNA tree. The Krasnodar population appeared to receive immigrants from other localities, but distinctive haplotypes from this locality did not appear elsewhere, suggesting asymmetric gene flow. Signatures of recent gene flow between northern populations were detected, and there was no evidence of isolation by distance within the northern group of populations. Mismatch distributions for most localities were consistent with population expansions. We also analyzed 12 male plumage characters from 93 study skins sampled from 24 populations. Phylogenetic trees resulting from separate genetic and morphological analyses were incongruent. Plumage evolution seems to be under strong sexual or natural selection, which favors particular phenotypes in various areas irrespective of the mitochondrial background. Dispersal events at different evolutionary times could have obscured the effects of earlier isolation events. The mtDNA data does not support species status for M. a. lugens and M. a. personata, which shared haplotypes with other subspecies of M. alba. We recommend that M. lugens and M. personata are placed as junior synonyms of M. alba.  相似文献   
75.
76.
The state of pulmonary surfactant in rabbits at different periods (3 to 60 days) of experimental pneumonia was compared with the changes of the redox enzymes in the alveolar epithelium and the cells of the inflammatory infiltrate. At the initial stage (3 to 7 days) of the cellular metabolism activation there occurred a transitory intensification of the synthesis of surfactant lipids with a relative suppression of phospholipid synthesis. Later the progress of dystrophic processes and parenchymal sclerosis was accompanied by reduction of the synthesis of all the surfactant components. Surfactant surface activity became stable at a low level. This is possibly connected with the specific regulation of the surfactant synthesis determined by functional peculiarities of the organ.  相似文献   
77.
The activity values, properties and peculiarities of activation of glycogen phosphorylase (GP, EC 2.4.1.1) and glycogen phosphorylase kinase (GPK, EC 2.7.138) were studied in the white skeletal muscle of fishes differing in motor behavior. No differences in the GP and GPK activity levels were revealed in porgy Diplodus annularis (L.), horse mackerel Trachurus mediterraneus ponticus, trout Salmo trutta morphario, scorpionfish Scorpaena porcus, flounder Scophtalnus maeoticus maeoticus, and carp Cyprinus carpio; however, properties of the isolated enzymes and peculiarities of formation of their activated forms during swimming in a hydrodynamic tube are determined by functional peculiarities of the muscle tissue and are associated with the motor activity character of the species. The more rapid ion regulation prevails in fishes capable for the burst swimming type (scorpionfish, trout). The glycogenolysis hormonal regulation leading to a change of the GPK activity index has been found in other species.  相似文献   
78.

Background

The multigene family encoding the 5S rRNA, one of the most important structurally-functional part of the large ribosomal subunit, is an obligate component of all eukaryotic genomes. 5S rDNA has long been a favored target for cytological and phylogenetic studies due to the inherent peculiarities of its structural organization, such as the tandem arrays of repetitive units and their high interspecific divergence. The complex polyploid nature of the genome of bread wheat, Triticum aestivum, and the technically difficult task of sequencing clusters of tandem repeats mean that the detailed organization of extended genomic regions containing 5S rRNA genes remains unclear. This is despite the recent progress made in wheat genomic sequencing. Using pyrosequencing of BAC clones, in this work we studied the organization of two distinct 5S rDNA-tagged regions of the 5BS chromosome of bread wheat.

Results

Three BAC-clones containing 5S rDNA were identified in the 5BS chromosome-specific BAC-library of Triticum aestivum. Using the results of pyrosequencing and assembling, we obtained six 5S rDNA- containing contigs with a total length of 140,417 bp, and two sets (pools) of individual 5S rDNA sequences belonging to separate, but closely located genomic regions on the 5BS chromosome. Both regions are characterized by the presence of approximately 70–80 copies of 5S rDNA, however, they are completely different in their structural organization. The first region contained highly diverged short-type 5S rDNA units that were disrupted by multiple insertions of transposable elements. The second region contained the more conserved long-type 5S rDNA, organized as a single tandem array. FISH using probes specific to both 5S rDNA unit types showed differences in the distribution and intensity of signals on the chromosomes of polyploid wheat species and their diploid progenitors.

Conclusion

A detailed structural organization of two closely located 5S rDNA-tagged genomic regions on the 5BS chromosome of bread wheat has been established. These two regions differ in the organization of both 5S rDNA and the neighboring sequences comprised of transposable elements, implying different modes of evolution for these regions.
  相似文献   
79.
Experimental preparations based on a DNA vaccine encoding the ESAT-6 antigen of Mycobacterium tuberculosis have been obtained (KpONE6) and studied for immunogenic effects in the murine model. The core of the preparation contains DNA of the recombinant plasmid pONE6 encapsulated within a spermidine-polyglucin conjugate, thereby protecting the DNA vaccine from degradation. KpONE6 induces a proliferative T-cell immune response in mice upon intramuscular immunization.  相似文献   
80.
We find that the prostate cancer cell lines ALVA-31, PC-3, and DU 145 are highly sensitive to apoptosis induced by TRAIL (tumor-necrosis factor-related apoptosis-inducing ligand), while the cell lines TSU-Pr1 and JCA-1 are moderately sensitive, and the LNCaP cell line is resistant. LNCaP cells lack active lipid phosphatase PTEN, a negative regulator of the phosphatidylinositol (PI) 3-kinase/Akt pathway, and demonstrate a high constitutive Akt activity. Inhibition of PI 3-kinase using wortmannin and LY-294002 suppressed constitutive Akt activity and sensitized LNCaP cells to TRAIL. Treatment of LNCaP cells with TRAIL alone induced cleavage of the caspase 8 and XIAP proteins. However, processing of BID, mitochondrial release of cytochrome c, activation of caspases 7 and 9, and apoptosis did not occur unless TRAIL was combined with either wortmannin, LY-294002, or cycloheximide. Blocking cytochrome c release by Bcl-2 overexpression rendered LNCaP cells resistant to TRAIL plus wortmannin treatment but did not affect caspase 8 or BID processing. This indicates that in these cells mitochondria are required for the propagation rather than the initiation of the apoptotic cascade. Infection of LNCaP cells with an adenovirus expressing a constitutively active Akt reversed the ability of wortmannin to potentiate TRAIL-induced BID cleavage. Thus, the PI 3-kinase-dependent blockage of TRAIL-induced apoptosis in LNCaP cells appears to be mediated by Akt through the inhibition of BID cleavage.  相似文献   
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