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901.
Expression of matrix metalloproteinase 9 in pancreatic ductal carcinoma is associated with tumor metastasis formation 总被引:4,自引:0,他引:4
Pryczynicz A Guzińska-Ustymowicz K Dymicka-Piekarska V Czyzewska J Kemona A 《Folia histochemica et cytobiologica / Polish Academy of Sciences, Polish Histochemical and Cytochemical Society》2007,45(1):37-40
The objective of the current study was to assess the expression of matrix metalloproteinase 9 (MMP-9) in pancreatic ductal carcinoma and to examine its correlation with chosen clinico-anatomical parameters. The study group consisted of 36 patients with pancreatic ductal carcinoma. Tumors were stained using immunohistochemical method (NCL -MMP-9, Novocastra). No correlation was found between tumor MMP-9 expression and age, gender or grade of histological malignancy. However, statistical analysis revealed a relationship between tumor MMP-9 expression and histological type (adenocarcinoma mucinosum) of pancreatic carcinoma. The expression was strongly correlated with lymph node involvement and occurrence of distant metastases (p<0.00001). The results indicate a correlation between the expression of MMP-9 in pancreatic ductal carcinoma and worse prognosis (shown by lymph node involvement and distant metastases). 相似文献
902.
Kumirska J Szafranek J Czerwicka M Paszkiewicz M Dziadziuszko H Kunikowska D Stepnowski P 《Carbohydrate research》2007,342(14):2138-2143
The structure of the O-antigenic part of the lipopolysaccharide (LPS) of Salmonella Dakar was analysed using chemical methods, NMR spectroscopy and mass spectrometry. The following structure for the repeating unit of the O-polysaccharide was determined: [see text] where Quip3NAc is 3-acetamido-3,6-dideoxyglucose. This is the first published structure of the O-polysaccharides from 101 serotypes of Salmonella bacteria belonging to serogroup O:28 (formerly M) in the Kauffmann-White scheme. 相似文献
903.
904.
Green synthesis of nanoparticles has gained significant importance in recent years and has become the one of the most preferred methods. Also, green synthesis of nanoparticles is valuable branch of nanotechnology. Plant extracts are eco-friendly and can be an economic option for synthesis of nanoparticles. This study presents method the synthesis of silver nanoparticles using water extract of Arnicae anthodium. Formation of silver nanoparticles was confirmed by UV–visble spectroscopy, Fourier transform infrared spectroscopy and total reflection X-ray fluorescence analysis. The morphology of the synthesized silver nanoparticles was verified by SEM–EDS. The obtained silver nanoparticles were used to study their antimicrobial activity. 相似文献
905.
906.
Jolanta Solecka Joanna Zajko Magdalena Postek Aleksandra Rajnisz 《Central European Journal of Biology》2012,7(3):373-390
Secondary metabolites obtained from Actinomycetales provide a potential source of many novel compounds with antibacterial, antitumour, antifungal, antiviral, antiparasitic and
other properties. The majority of these compounds are widely used as medicines for combating multidrug-resistant Gram-positive
and Gram-negative bacterial strains. Members of the genus Streptomyces are profile producers of previously-known secondary metabolites. Actinomycetes have been isolated from terrestrial soils,
from the rhizospheres of plant roots, and recently from marine sediments. This review demonstrates the diversity of secondary
metabolites produced by actinomycete strains with respect to their chemical structure, biological activity and origin. On
the basis of this diversity, this review concludes that the discovery of new bioactive compounds will continue to pose a great
challenge for scientists. 相似文献
907.
BACKGROUND: The goal of our study was to examine spontaneous and stimulated apoptosis of peripheral blood MNC from allergic patients, sensitized to Der p I antigen as compared to cells from non-atopic subjects. Furthermore we aimed to investigate which populations of mononuclear cells (lymphocytes, monocytes) undergo the apoptosis and to determine relations between apoptosis and serum levels of sFas/APO-1, ICE/caspase-1 or TNF-alpha. METHODS: The study included 17 patients with perennial, allergic asthma and/or allergic rhinitis [6 male and 11 female; mean age 29,5 years; (range 15-49)]. Apoptosis was assessed by fluorescence technique and confirmed by flow-cytometric method and DNA ladder. Serum levels of sFas, ICE/caspase-1 or TNF-alpha were determined by immunoassays (ELISA). RESULTS: Apoptotic index of unfractionated mononuclear cells (MNC) and lymphocytes (but not monocytes) were significantly higher in allergic patients as compared to non-allergic subjects after 48 and 72 hours of culture (p<0.05). Incubation of cells with ConA (10 microg/ml) resulted in a significant increase in the proportion of apoptotic cells in all populations once the apoptotic index for MNC and lymphocytes (but not monocytes) was again significantly higher in allergic as compared to non-allergic subjects after 24, 48 and 72 hour of culture. In allergic patients, mean serum sFas level, was significantly lower then in non-allergic group (mean value 624.8 pg/ml +/- 25.67 versus 802.0 pg/ml +/- 31.91; p = 0.003) and in both groups sFas level correlated inversely with apoptosis of MNC. The mean ICE/caspase-1 concentration was significantly higher in sera of allergic patients as compared to non-allergic group (mean value 27.71 pg/ml +/- 3.79 vs 23.54 pg/ml respectively; p<0.01). ICE/caspase-1 levels in allergic patients correlated with apoptotic index of mononuclear cells (r = 0.57; p<0.001). CONCLUSIONS: An increased spontaneous and mitogen-induced apoptosis of MNC from peripheral blood of atopic patients as well as different serum levels of sFas and ICE/caspase-1 correlating with apoptosis, suggest different regulation of apoptotic process in peripheral blood mononuclear cells of patients with allergic asthma and/or rhinitis. 相似文献
908.
Dorszewska J Florczak J Rózycka A Jaroszewska-Kolecka J Trzeciak WH Kozubski W 《DNA and cell biology》2005,24(12):786-794
The study aimed at the analysis of polymorphisms in the gene coding for the nicotinic acetylcholine receptor alpha4 subunit (CHRNA4) and the evaluation of the extent of the oxidative damage to DNA (8-oxo2dG), as well as the level of proteins participating in DNA repair (p53, PARP) and DNA degradation (Bax:Bcl-2, 85-kDa fragment) in the peripheral blood lymphocytes of the patients suffering from Alzheimer's disease (AD) and in the healthy individuals of the control group. In the AD patients the increased levels of oxidized guanine were demonstrated in DNA, accompanied by the elevated expression of p53, Bax, PARP, and of a 85-kDa protein subunit as well as an augmented ratio of Bax:Bcl-2. Also, the level of Bcl-2 protein was decreased. In the AD patients with the CHRNA4 polymorphisms the highest level of 8-oxo2dG and of proteins involved in DNA repair were documented in patients with polymorphisms in exon 5, in contrast to the patients with polymorphisms in intron 5. In the former patients, levels of pro- and antiapoptotic proteins remained at the same level. Both CHRNA4 polymorphisms and the extent of dementia seem to affect the levels of DNA oxidative damage as well as to activate factors that participate in the DNA degradation and its repair. 相似文献
909.
Mackiewicz P Zakrzewska-Czerwinska J Zawilak A Dudek MR Cebrat S 《Nucleic acids research》2004,32(13):3781-3791
Three methods, based on DNA asymmetry, the distribution of DnaA boxes and dnaA gene location, were applied to identify the putative replication origins in 120 chromosomes. The chromosomes were classified according to the agreement of these methods and the applicability of these methods was evaluated. DNA asymmetry is the most universal method of putative oriC identification in bacterial chromosomes, but it should be applied together with other methods to achieve better prediction. The three methods identify the same region as a putative origin in all Bacilli and Clostridia, many Actinobacteria and gamma Proteobacteria. The organization of clusters of DnaA boxes was analysed in detail. For 76 chromosomes, a DNA fragment containing multiple DnaA boxes was identified as a putative origin region. Most bacterial chromosomes exhibit an overrepresentation of DnaA boxes; many of them contain at least two clusters of DnaA boxes in the vicinity of the oriC region. The additional clusters of DnaA boxes are probably involved in controlling replication initiation. Surprisingly, the characteristic features of the initiation of replication, i.e. a cluster of DnaA boxes, a dnaA gene and a switch in asymmetry, were not found in some of the analysed chromosomes, particularly those of obligatory intracellular parasites or endosymbionts. This is presumably connected with many mechanisms disturbing DNA asymmetry, translocation or disappearance of the dnaA gene and decay of the Escherichia coli perfect DnaA box pattern. 相似文献
910.
We present the characteristics of the Csm1 (Spo86) protein of Saccharomyces cerevisiae that are important for meiotic division. The level of Csm1p does not change throughout the cell cycle, but this protein is absent in mature spores. Deletion of CSM1 causes incorrect spore formation and meiotic chromosome missegregation together with increased sensitivity of vegetative cells to benomyl and manganese. In a two-hybrid analysis with Csm1p as bait, we detected interactions with three members of the Mcm2-7 family of proteins involved in the initiation of DNA replication, and with Clf1p also implicated in replication. The Csm1p-Mcm3, Mcm5 and Mcm7p interactions were confirmed by co-immunoprecipitation. Three other interacting proteins, Mgs1p, Ulp2, and Plp2, participate in chromosome assembling and segregation, whereas the function of two others has not been established. Genetic experiments showed that the two-hybrid isolates MGS1, CLF1, MCM3, 5, 7 (CDC47), and YDL089w, when overexpressed, partially suppress the csm1Delta/csm1Delta sporulation defect. We propose that, besides its other functions, Csm1p may be involved in premeiotic DNA replication. 相似文献