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91.
Molecular strategies in Metazoan genomic evolution 总被引:2,自引:0,他引:2
92.
Poggi A Zocchi MR Carosio R Ferrero E Angelini DF Galgani S Caramia MD Bernardi G Borsellino G Battistini L 《Journal of immunology (Baltimore, Md. : 1950)》2002,168(12):6071-6077
We have previously reported that the Vdelta2(+)TCRgammadelta(+) T lymphocyte subset, expressing the NK receptor protein 1a (NKRP1a; CD161), is expanded in patients with relapsing-remitting multiple sclerosis and uses this molecule to migrate through endothelium. In this work, we show that Vdelta1(+) and Vdelta2(+) gammadelta T lymphocytes use distinct signal transduction pathways to accomplish this function. Indeed, we have found that Vdelta1(+) cells lack NKRP1a and selectively express the platelet endothelial cell adhesion molecule 1 (PECAM1; CD31), which drives transendothelial migration of this cell subset, at variance with Vdelta2(+) T cells, which are PECAM1 negative and use NKRP1a for transmigration. Interestingly, when Vdelta2(+) T cells were pretreated with two specific inhibitors of the calcium calmodulin-dependent kinase II KN62 and KN93, but not with the inactive compound KN92, the number of migrating cells and the rate of transmigration were significantly decreased. In turn, the phosphatidylinositol 3 kinase blockers wortmannin and LY294002 exerted a dose-dependent inhibition of Vdelta1(+) cell migration. Finally, NKRP1a and PECAM1 engagement led to activation of different signal transduction pathways: indeed, oligomerization of NKRP1a on Vdelta2(+) T cells activates calcium calmodulin-dependent kinase II, while occupancy of PECAM1 on Vdelta1(+) cells triggers the phosphatidylinositol 3 kinase-dependent Akt/protein kinase Balpha activation. These findings suggest that subsets of gammadelta T lymphocytes may migrate to the site of lesion in multiple sclerosis using two different signaling pathways to extravasate. 相似文献
93.
Large and dissimilar repertoire of Melan-A/MART-1-specific CTL in metastatic lesions and blood of a melanoma patient 总被引:4,自引:0,他引:4
Mandruzzato S Rossi E Bernardi F Tosello V Macino B Basso G Chiarion-Sileni V Rossi CR Montesco C Zanovello P 《Journal of immunology (Baltimore, Md. : 1950)》2002,169(7):4017-4024
It is widely accepted that the repertoire of Melan-A-specific T cells naturally selected in melanoma patients is diverse and mostly nonoverlapping among different individuals. To date, however, no studies have addressed the TCR profile in different tumor sites and the peripheral blood from the same patient. We compared the TCR usage of Melan-A-specific T cells from different compartments of a single melanoma patient to evaluate possible clonotype expansion or preferential homing over a 4-mo follow-up period. Using HLA-A2 peptide tetramers, CD8(+) T cells recognizing the modified Melan-A immunodominant ELAGIGILTV peptide were isolated from four metastatic lesions resected from a single melanoma patient, and their TCR repertoire was studied. A panel of T cell clones was generated by cell cloning of tetramer-positive cells. Analysis of the TCR beta-chain V segment and the complementarity-determining region 3 (CDR3) length and sequence revealed a large diversity in the TCR repertoire, with only some of the clones showing a partial conservation in the CDR3. A similar degree of diversity was found by analyzing a number of T cell clones obtained after sorting a Melan-A-specific population derived from PBLs of the same patient after in vitro culture with the immunodominant epitope. Moreover, clonotypes found at one site were not present in another, suggesting the lack of expansion and circulation of one or more clonotypes. Taken together, these results buttress the notion that the CTLs recognizing the immunodominant Ag of Melan-A comprise a high number of different clonotypic TCR, of which only some exhibit common features in the CDR3. 相似文献
94.
Mazzolla R Puliti M Barluzzi R Neglia R Bistoni F Barbolini G Blasi E 《FEMS immunology and medical microbiology》2002,32(2):149-158
In mice, the gene encoding Nramp1 (natural resistance-associated protein 1) exists in two allelic forms, differing for a point mutation. According to Nramp1 genotype, extensive literature documents a clear-cut distinction of inbred strains in two non-overlapping groups that phenotypically express resistance (Nramp1r) and susceptibility (Nramp1s) to systemic infections. Here, we provide evidence that Nramp1r (DBA/2) and Nramp1s (Balb/c) mice differently handle intracerebral infection with Mycobacterium bovis BCG. Distinct trends of microbial clearance from the brain and also different patterns of local immune responses occur, thus arguing on the involvement of Nramp1 gene product on the accomplishment of cerebral anti-mycobacterial defenses. 相似文献
95.
96.
Monitoring the effects of drug treatment in rat models of disease by serum protein analysis 总被引:5,自引:0,他引:5
Gianazza E Eberini I Villa P Fratelli M Pinna C Wait R Gemeiner M Miller I 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2002,771(1-2):107-130
In this review we list from literature investigations on rat serum proteins using electrophoretic techniques in connection with drug testing. From our own research work, we provide annotated two-dimensional maps of rat serum proteins under control and experimental conditions. Emphasis is on species-specific components and on the effects of acute and chronic inflammation. We discuss our project of structural proteomics on rat serum as a minimally invasive approach to pharmacological investigation, and we outline a typical experimental plan for drug testing according to the above guidelines. We then report in detail on the results of our trials of anti-inflammatory drugs on adjuvant arthritis, an animal model of disease resembling in many aspects human rheumatoid arthritis. We demonstrate a correlation between biochemical parameters and therapeutic findings and outline the advantages of the chosen methodological approach, which proved also sensitive in revealing "side effects" of the test drugs. In an appendix we describe our experimental protocol when performing two-dimensional electrophoresis of rat serum. 相似文献
97.
Franciotta D Martino G Zardini E Furlan R Bergamaschi R Gironi M Bergami A Angelini G De Benedetti F Pignatti P Moscato G Cosi V 《European cytokine network》2002,13(1):99-103
In multiple sclerosis (MS), pathological white matter damage in the central nervous system is sustained by immune-inflammatory response. Caspase-1 plays a pivotal role in immune-mediated inflammation, as it regulates the cellular export of IL-1beta and IL-18. We carried out a preliminary in vitro study of the kinetics of extracellular caspase-1 release. We then measured caspase-1 levels in paired serum and cerebrospinal fluid (CSF) samples of 75 MS patients, 15 healthy subjects, and patients with other neurological diseases. Paired synovial fluid and serum samples of patients with juvenile idiopathic arthritis, and paired sputum and serum samples of asthma patients were also studied. Mean serum caspase-1 concentrations did not differ between groups. Caspase-1 was detected in the CSF of patients with acute, but not stable, MS [7.5 +/- (SEM) 0.9 pg/ml; test's sensitivity, 56% and specificity, 100%]. Its levels correlated with pleocytosis. The highest mean caspase-1 levels were found in the arthritic synovial fluids (945.5 +/- 126.6 pg/ml, which correlated with erythrocyte sedimentation rate), and in the sputum samples (370.1 +/- 71.0 pg/ml, which correlated with the number of macrophages in the sputum). On condition that caspase-1 is determined in the fluids pertaining to the disease-specific inflammatory sites, its level is a reliable marker of ongoing immune-inflammatory response. The enzyme measurement in CSF can also help define state-trait in MS. 相似文献
98.
p53 is one of the most mutated genes in human cancer. We have performed the molecular characterization of p53 and have searched
for correlations with etiological factors and clinical parameters in primary and secondary liver tumors.
A systematic study was carried out, innovative in many respects, to determine the mutational pattern of all 11 exons of p53
and analysis was extended also to exons 1–4 and 9–11 and the exon/intron junctions.
Our analyses were performed on case histories of 114 patients from the European area and highlighted p53 mutation patterns
different from those reported in the literature for the same tumors. In our case history, different tumors of the same organ
showed a different frequency and distribution of mutations.
In analyzed tumor types, gene status was a prognostic indicator of survival because patients undergoing liver resection without
mutated p53 had a more favorable prognosis than mutated patients. This suggests p53 molecular diagnosis could become a further
criterion in the decision for surgery and possible therapies.
We describe the ideal conditions for polymerase chain reaction (PCR), single-strand conformation polymorphism (SSCP), and
direct sequencing, which we have set in order to optimize yields, sensitivity, and time of what might become a massive molecular
screening. 相似文献
99.
In several species of the Oleaceae, mannitol, already present at considerable levels, accumulates in response to stress. This family comprises both deciduous and evergreen species, and we investigated the role of mannitol in deciduous malacophyll and evergreen sclerophyll species growing under the same conditions in the field. The relationship between mannitol content and changes in rainfall or temperature was also studied. The mannitol content of leaves of Fraxinus ornus L., F. angustifolia Vahl., Olea europaea L. and Phillyrea media L. was determined by gas chromatography. Leaf samples were collected once a month for 1 year. In the two ash species, the seasonal pattern of mannitol content appeared the same: a gradual increase in spring, peaking in summer, followed by a gradual decrease. The mannitol content was similar in both species, ranging between 260 and 720 micromol g(-1) d. wt. The seasonal pattern of mannitol content in Olea and Phillyrea was similar for both species, but unlike that of Fraxinus did not show a summer peak. Rainfall was negatively correlated with the seasonal increase of mannitol content in ash. Mannitol content increased gradually during drought, reaching a maximum value at the end of the dry season. Temperature did not have a direct influence on mannitol content. In Olea and Phillyrea, variations in mannitol content were poorly correlated with rainfall or temperature, indicating that mannitol does not have a primary role in the response of these species to the hot, dry summer conditions. 相似文献
100.
Czene S Testa E Nygren J Belyaev I Harms-Ringdahl M 《Biochemical and biophysical research communications》2002,294(4):872-878
Cell suspensions enriched in cells at various stages of apoptosis were obtained by separation of irradiated human peripheral blood lymphocytes on density gradients at different post-irradiation times. The state of DNA fragmentation in the cells was determined by comet assay and pulsed field gel electrophoresis. The morphologically distinguishable features of apoptosis such as chromatin condensation and cell shrinkage correlated with discrete stages of DNA fragmentation. It was found that >/=50 kbp fragmentation of DNA occurs already in cells of normal density whereas the subsequent DNA fragmentation onto fragments <50 kbp occurs in parallel with cell shrinkage and simultaneous increase in cell density.The observed stages of DNA fragmentation seem to be separated in time that could allow in case of abortive apoptosis formation of chromosomal aberrations. 相似文献