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111.
Djabarouti S Breilh D Duffau P Lazaro E Greib C Caubet O Saux MC Pellegrin JL Viallard JF 《Arthritis research & therapy》2010,12(6):R217
Introduction
The aim of this study was to determine whether mycophenolate mofetil (MMF) pharmacokinetics (PK) under combined MMF and prednisone remission-maintenance therapy can predict systemic lupus erythematosus (SLE) clinical flares. 相似文献112.
Vallois D Gagnerault MC Avner P Rogner UC Boitard C Benlagha K Herbelin A Lepault F 《Journal of immunology (Baltimore, Md. : 1950)》2008,181(3):1753-1759
The number and function of immunoregulatory invariant NKT (iNKT) cells are genetically controlled. A defect of iNKT cell ontogeny and function has been implicated as one causal factor of NOD mouse susceptibility to type 1 diabetes. Other factors of diabetes susceptibility, such as a decrease of regulatory T cell function or an increase in TLR1 expression, are corrected in diabetes-resistant Idd6 NOD.C3H 6.VIII congenic mice. Thus, we surmised that the iNKT cell defects found in NOD mice may also be rescued in congenic mice. Unexpectedly, we found, in both the thymus and the periphery, a 50% reduction in iNKT cell number in NOD.C3H 6.VIII mice as compared with NOD mice. This reduction only affected CD4(+) iNKT cells, and left the double negative iNKT cells unchanged. In parallel, the production of IL-4 and IFN-gamma following alpha-GalCer stimulation was proportionally reduced. Using three subcongenic strains, we have narrowed down the region controlling iNKT development within Idd6 (5.8 Mb) to Idd6.2 region (2.5 Mb). Idd6 region had no effect on NK cell number and in vivo cytotoxic activity. These results indicate that the role of iNKT cells in diabetes development is equivocal and more complex than initially considered. In addition, they bring strong evidence that the regulation of CD4(+) iNKT cell production is independent from that of DN iNKT cells, and involves genes of the Idd6 locus. 相似文献
113.
Alexandre Sasseville Dalila Benhaberou-Brun Charlotte Fontaine Marie-Claude Charon 《Chronobiology international》2013,30(5):913-925
Night shiftworkers often complain of disturbed sleep during the day. This could be partly caused by morning sunlight exposure during the commute home, which tends to maintain the circadian clock on a daytime rhythm. The circadian clock is most sensitive to the blue portion of the visible spectrum, so our aim was to determine if blocking short wavelengths of light below 540 nm could improve daytime sleep quality and nighttime vigilance of night shiftworkers. Eight permanent night shiftworkers (32–56 yrs of age) of Quebec City's Canada Post distribution center were evaluated during summertime, and twenty others (24–55 yrs of age) during fall and winter. Timing, efficacy, and fragmentation of daytime sleep were analyzed over four weeks by a wrist activity monitor, and subjective vigilance was additionally assessed at the end of the night shift in the fall–winter group. The first two weeks served as baseline and the remaining two as experimental weeks when workers had to wear blue-blockers glasses, either just before leaving the workplace at the end of their shift (summer group) or 2 h before the end of the night shift (fall–winter group). They all had to wear the glasses when outside during the day until 16:00 h. When wearing the glasses, workers slept, on average ±SD, 32±29 and 34±60 more min/day, increased their sleep efficacy by 1.95±2.17% and 4.56±6.1%, and lowered their sleep fragmentation by 1.74±1.36% and 4.22±9.16% in the summer and fall–winter group, respectively. Subjective vigilance also generally improved on Fridays in the fall–winter group. Blue-blockers seem to improve daytime sleep of permanent night-shift workers. 相似文献
114.
Moore MM Honma M Clements J Bolcsfoldi G Cifone M Delongchamp R Fellows M Gollapudi B Jenkinson P Kirby P Kirchner S Muster W Myhr B O'Donovan M Oliver J Omori T Ouldelhkim MC Pant K Preston R Riach C San R Stankowski LF Thakur A Wakuri S Yoshimura I;Mouse Lymphoma Assay Workgroup 《Mutation research》2003,540(2):127-140
The Mouse Lymphoma Assay (MLA) Workgroup of the International Workshop on Genotoxicity Tests (IWGT) met on June 28th and 29th, 2002, in Plymouth, England. This meeting of the MLA group was devoted to discussing the criteria for assay acceptance and appropriate approaches to data evaluation. Prior to the meeting, the group conducted an extensive analysis of data from both the microwell and soft agar versions of the assay. For the establishment of criteria for assay acceptance, 10 laboratories (6 using the microwell method and 4 using soft agar) provided data on their background mutant frequencies, plating efficiencies of the negative/vehicle control, cell suspension growth, and positive control mutant frequencies. Using the distribution curves generated from this data, the Workgroup reached consensus on the range of values that should be used to determine whether an individual experiment is acceptable. In order to establish appropriate approaches for data evaluation, the group used a number of statistical methods to evaluate approximately 400 experimental data sets from 10 laboratories entered into a database created for the earlier MLA Workshop held in New Orleans [Environ. Mol. Mutagen. 40 (2002) 292]. While the Workgroup could not, during this meeting, make a final recommendation for the evaluation of data, a general strategy was developed and the Workgroup members agreed to evaluate this new proposed approach using their own laboratory data. This evaluation should lead to a consensus global approach for data evaluation in the near future. 相似文献
115.
Asma Tlili Alexander Hoischen Clémentine Ripoll Eva Benabou Anne Badel Anne Ronan Renaud Touraine Yann Grattau Samantha Stora Bregje van Bon Bert de Vries Bj?rn Menten Nele Bockaert Joseph Gecz Stylianos E. Antonarakis Dominique Campion Marie-Claude Potier Henri Bléhaut Jean-Maurice Delabar Nathalie Janel 《Molecular neurobiology》2012,46(2):297-303
Down syndrome or trisomy 21 is the most common genetic disorder leading to mental retardation. One feature is impaired short- and long-term spatial memory, which has been linked to altered brain-derived neurotrophic factor (BDNF) levels. Mouse models of Down syndrome have been used to assess neurotrophin levels, and reduced BDNF has been demonstrated in brains of adult transgenic mice overexpressing Dyrk1a, a candidate gene for Down syndrome phenotypes. Given the link between DYRK1A overexpression and BDNF reduction in mice, we sought to assess a similar association in humans with Down syndrome. To determine the effect of DYRK1A overexpression on BDNF in the genomic context of both complete trisomy 21 and partial trisomy 21, we used lymphoblastoid cell lines from patients with complete aneuploidy of human chromosome 21 (three copies of DYRK1A) and from patients with partial aneuploidy having either two or three copies of DYRK1A. Decreased BDNF levels were found in lymphoblastoid cell lines from individuals with complete aneuploidy as well as those with partial aneuploidies conferring three DYRK1A alleles. In contrast, lymphoblastoid cell lines from individuals with partial trisomy 21 having only two DYRK1A copies displayed increased BDNF levels. A negative correlation was also detected between BDNF and DYRK1A levels in lymphoblastoid cell lines with complete aneuploidy of human chromosome 21. This finding indicates an upward regulatory role of DYRK1A expression on BDNF levels in lymphoblastoid cell lines and emphasizes the role of genetic variants associated with psychiatric disorders. 相似文献
116.
Fauchais AL Lalloué F Lise MC Boumediene A Preud'homme JL Vidal E Jauberteau MO 《Journal of immunology (Baltimore, Md. : 1950)》2008,181(5):3027-3038
Brain-derived neurotrophic factor (BDNF), a major neuronal growth factor, is also known to exert an antiapoptotic effect in myeloma cells. Whereas BDNF secretion was described in B lymphocytes, the ability of B cells to produce sortilin, its transport protein, was not previously reported. We studied BDNF production and the expression of its receptors, tyrosine protein kinase receptor B and p75 neurotrophin receptor in the human pre-B, mature, and plasmacytic malignant B cell lines under normal and stress culture conditions (serum deprivation, Fas activation, or their combination). BDNF secretion was enhanced by serum deprivation and exerted an antiapoptotic effect, as demonstrated by neutralization experiments with antagonistic Ab. The precursor form, pro-BDNF, also secreted by B cells, decreases under stress conditions in contrast to BDNF production. Stress conditions induced the membranous expression of p75 neurotrophin receptor and tyrosine protein kinase receptor B, maximal in mature B cells, contrasting with the sequestration of both receptors in normal culture. By blocking Ab and small interfering RNA, we evidenced that BDNF production and its survival function are depending on sortilin, a protein regulating neurotrophin transport in neurons, which was not previously described in B cells. Therefore, in mature B cell lines, an autocrine BDNF production is up-regulated by stress culture conditions and exerts a modulation of apoptosis through the sortilin pathway. This could be of importance to elucidate certain drug resistances of malignant B cells. In addition, primary B lymphocytes contained sortilin and produced BDNF after mitogenic activation, which suggests that sortilin and BDNF might be implicated in the survival and activation of normal B cells also. 相似文献
117.
Christelle David Laurent Bischoff Hervé Meudal Catherine Llorens-Cortes Bernard Pierre Roques Marie-Claude Fournié-Zaluski 《International journal of peptide research and therapeutics》1997,4(4-6):411-414
Summary In order to study the physiological role of aminopeptidase A(APA), several α-mercapto-β-amino acyl dipeptides were synthesized
to obtain compounds having a high affinity for APA and a high selectivity versus aminopeptidase N (APN). Sulfornamide and
carboxylate moieties which have been shown to be recognized by the S1 subsite of the enzyme were introduced on the side chain of the α-mercapto-β-amino acyl sub-unit, the latter being coupled
to dipeptides optimized to interact with the S'1 and S'2 subsites by means of combinatorial chemistry. Good affinities (16nM) were obtained, the selectivity factors being up to 160-fold
versus APN. 相似文献
118.
We analyzed here the expression of the prosurvival Bcl-2 homologue A1 in peripheral B cell compartment. We observed that A1 mRNA are highly expressed in peripheral B cells as compared with other anti-apoptotic genes of the Bcl-2 family such as bcl-xl and bcl-2 itself. The expression of A1 is up-regulated in immature B cells at the transition between transitional type 1 (T1) and type 2 (T2) cells, and remained highly expressed in mature (M) B cells. We, therefore, analyzed the effect of B cell antigen receptor (BCR) and BAFF receptor (BAFF-R) engagement on the regulation of A1 in total B220(+) cells but also FACS-sorted immature T1, T2 and M B cells. We demonstrated that only BCR engagement up-regulated the expression of A1 mRNA and protein. These results suggest that A1 may play a key role in antigen-dependent signals that are required for survival and/or proliferation of peripheral B cells. 相似文献
119.
Nováková L Sasková L Pallová P Janecek J Novotná J Ulrych A Echenique J Trombe MC Branny P 《The FEBS journal》2005,272(5):1243-1254
Searching the genome sequence of Streptococcus pneumoniae revealed the presence of a single Ser/Thr protein kinase gene stkP linked to protein phosphatase phpP. Biochemical studies performed with recombinant StkP suggest that this protein is a functional eukaryotic-type Ser/Thr protein kinase. In vitro kinase assays and Western blots of S. pneumoniae subcellular fractions revealed that StkP is a membrane protein. PhpP is a soluble protein with manganese-dependent phosphatase activity in vitro against a synthetic substrate RRA(pT)VA. Mutations in the invariant aspartate residues implicated in the metal binding completely abolished PhpP activity. Autophosphorylated form of StkP was shown to be a substrate for PhpP. These results suggest that StkP and PhpP could operate as a functional pair in vivo. Analysis of phosphoproteome maps of both wild-type and stkP null mutant strains labeled in vivo and subsequent phosphoprotein identification by peptide mass fingerprinting revealed two possible substrates for StkP. The evidence is presented that StkP can phosphorylate in vitro phosphoglucosamine mutase GlmM which catalyzes the first step in the biosynthetic pathway leading to the formation of UDP-N-acetylglucosamine, an essential common precursor to cell envelope components. 相似文献
120.
Bon Marie-Claude Bonal Damien Goh Doreen K. Monteuuis Olivier 《Plant Cell, Tissue and Organ Culture》1998,53(3):171-177
The influence of five different macronutrient formulations and various growth regulators on micropropagation of single node
explants from Acacia mangium and Paraserianthes falcataria seedlings was examined after 4 weeks and 8 weeks in vitro. The
experiment was repeated 4 months later. On media lacking growth regulators, growth and development were significantly influenced
by the different macronutrient solutions tested, although morphogenic responses could vary according to the species. For instance,
P. falcataria displayed a greater ability for adventitious rooting than A. mangium. Overall, Knop macronutrient solution induced
the weakest responses. Explant responsiveness was significantly influenced by the addition of 2.2 or 4.4 μM 6-benzyladenine
combined with either 1.4 or 2.3 μM kinetin, 1.5 or 2.5 μM indolebutyric acid or 1.6 or 2.7 μM naphthaleneacetic acid. The
various combinations of growth regulators tested were shown to inhibit the rooting ability of the explants, while stimulating
the production of basal shoots for both species, and of axillary shoots only for A. mangium. In such experimental conditions,
A. mangium displayed overall a greater potential for micropropagation than P. falcataria.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献