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121.
Primary T-cell activation at mucosal sites is of utmost importance for the development of vaccination strategies. T-cell priming after vaginal immunization, with ovalbumin and CpG oligodeoxynucleotide adjuvant as model vaccine formulation, was studied in vivo in hormone-synchronized mice and compared to the one induced by the nasal route. Twenty-four hours after both vaginal or nasal immunization, antigen-loaded dendritic cells were detected within the respective draining lymph nodes. Vaginal immunization elicited a strong recruitment of antigen-specific CD4+ T cells into draining lymph nodes that was more rapid than the one observed following nasal immunization. T-cell clonal expansion was first detected in iliac lymph nodes, draining the genital tract, and proliferated T cells disseminated towards distal lymph nodes and spleen similarly to what observed following nasal immunization. T cells were indeed activated by the antigen encounter and acquired homing molecules essential to disseminate towards distal lymphoid organs as confirmed by the modulation of CD45RB, CD69, CD44 and CD62L marker expression. A multi-type Galton Watson branching process, previously used for in vitro analysis of T-cell proliferation, was applied to model in vivo CFSE proliferation data in draining lymph nodes 57 hours following immunization, in order to calculate the probabilistic decision of a cell to enter in division, rest in quiescence or migrate/die. The modelling analysis indicated that the probability of a cell to proliferate was higher following vaginal than nasal immunization. All together these data show that vaginal immunization, despite the absence of an organized mucosal associated inductive site in the genital tract, is very efficient in priming antigen-specific CD4+ T cells and inducing their dissemination from draining lymph nodes towards distal lymphoid organs.  相似文献   
122.
Genetic diversity and relationship among 3 Sicilian horse breeds were investigated using 16 microsatellite markers and a 397-bp length mitochondrial D-loop sequence. The analysis of autosomal DNA was performed on 191 horses (80 Siciliano [SIC], 61 Sanfratellano [SAN], and 50 Sicilian Oriental Purebred [SOP]). SIC and SAN breeds were notably higher in genetic variability than the SOP. Genetic distances and cluster analysis showed a close relationship between SIC and SAN breeds, as expected according to the breeds' history. Sequencing of hypervariable mitochondrial DNA region was performed on a subset of 60 mares (20 for each breed). Overall, 20 haplotypes with 31 polymorphic sites were identified: A higher haplotype diversity was detected in SIC and SAN breeds, with 13 and 11 haplotypes respectively, whereas only one haplotype was found in SOP. These were compared with 118 sequences from GenBank. BLAST showed that 17 of the 20 haplotypes had been reported previously in other breeds. One haplotype, found in SIC, traces back to a Bronze Age archaeological site (Inner Mongolia). The 3 Sicilian breeds are now rare, and 2 of them are officially endangered. Our results represent a valuable tool for management strategies as well as for conservation purposes.  相似文献   
123.
The main causes of familial hypercholesterolemia (FH) are mutations in LDL receptor (LDLR) gene. Functional studies are necessary to demonstrate the LDLR function impairment caused by mutations and would be useful as a diagnostic tool if they allow discrimination between FH patients and controls. In order to identify the best method to detect LDLR activity, we compared continuous Epstein-Barr virus (EBV)-transformed B-lymphocytes and mitogen stimulated T-lymphocytes. In addition, we characterized both novel and known mutations in the LDLR gene. T-lymphocytes and EBV-transformed B-lymphocytes were obtained from peripheral blood of 24 FH patients and 24 control subjects. Functional assays were performed by incubation with fluorescent LDL followed by flow cytometry analysis. Residual LDLR activity was calculated normalizing fluorescence for the mean fluorescence of controls. With stimulated T-lymphocytes we obtained a better discrimination capacity between controls and FH patients compared with EBV-transformed B-lymphocytes as demonstrated by receiver operating characteristic (ROC) curve analysis (the areas under the curve are 1.000 and 0.984 respectively; P < 0.0001 both). The characterization of LDLR activity through T-lymphocytes is more simple and faster than the use of EBV-transformed B-lymphocytes and allows a complete discrimination between controls and FH patients. Therefore the evaluation of residual LDLR activity could be helpful not only for mutation characterization but also for diagnostic purposes.  相似文献   
124.
Our ongoing research to identify natural growth inhibitors with diterpene and triterpene skeletons exuding from the surface of the aerial parts of Salvia species led us to study Salvia miniata Fernald. Ten clerodane diterpenoids were found, along with three known diterpenes. Most of the isolated compounds from S. miniata inhibited the germination of Papaver rhoeas L. and Avena sativa L. in Petri dish experiments. Parallel results have been obtained in experiments carried out to evaluate the subsequent growth of the seedlings of the target species in the presence of the tested compounds.  相似文献   
125.
Natural hybridization is widespread among food-deceptive orchids, whereas hybridization between deceptive and rewarding species is less common among Mediterranean species and its evolutionary consequences remain under-investigated. Here, we examine the morphological variation in floral traits, pollination success and demographic dynamics of natural hybrids between the widespread nectar-rewarding Anacamptis fragrans and the Mallorca endemic, food-deceptive A. robusta. We confirmed the status of hybrids using ribosomal DNA and assessed their maternal contribution using length polymorphism in the plastid tRNALEU intron. Genetic analyses confirmed that hybridization occurred in both directions, but the hybrids were morphologically closer in floral metric characters to A. fragrans and exhibited reduced among-individual variation in floral traits. No obvious secreting papillae were present in the hybrid spur, which more closely resembled the spur of non-rewarding A. robusta, reinforcing field observations that hybrids were probably nectarless. Compared with both rewarding and deceptive parents, the hybrids were less attractive for pollinators, most likely because of the absence of significant reward and of their combination of contrasting parental floral advertisements. In spite of its low pollination success, the hybrid population is presently expanding alongside the endemic A. robusta, suggesting that it follows the demographic dynamics of the parental species.  相似文献   
126.
For almost three decades in many countries azathioprine has been used to treat relapsing-remitting multiple sclerosis. However its efficacy was usually considered marginal and following approval of β interferons for this indication it was no longer recommended as first line treatment, even if presently no conclusive direct β interferon-azathioprine comparison exists. To compare azathioprine efficacy versus the currently available β interferons in relapsing-remitting multiple sclerosis, a multicenter, randomized, controlled, single-blinded, non-inferiority trial was conducted in 30 Italian multiple sclerosis centers. Eligible patients (relapsing-remitting course; ≥2 relapses in the last 2 years) were randomly assigned to azathioprine or β interferons. The primary outcome was annualized relapse rate ratio (RR) over 2 years. Key secondary outcome was number of new brain MRI lesions. Patients (n = 150) were randomized in 2 groups (77 azathioprine, 73 β interferons). At 2 years, clinical evaluation was completed in 127 patients (62 azathioprine, 65 β interferons). Annualized relapse rate was 0.26 (95% Confidence Interval, CI, 0.19–0.37) in the azathioprine and 0.39 (95% CI 0.30–0.51) in the interferon group. Non-inferiority analysis showed that azathioprine was at least as effective as β interferons (relapse RRAZA/IFN 0.67, one-sided 95% CI 0.96; p<0.01). MRI outcomes were analyzed in 97 patients (50 azathioprine and 47 β interferons). Annualized new T2 lesion rate was 0.76 (95% CI 0.61–0.95) in the azathioprine and 0.69 (95% CI 0.54–0.88) in the interferon group. Treatment discontinuations due to adverse events were higher (20.3% vs. 7.8%, p = 0.03) in the azathioprine than in the interferon group, and concentrated within the first months of treatment, whereas in the interferon group discontinuations occurred mainly during the second year.The results of this study indicate that efficacy of azathioprine is not inferior to that of β interferons for patients with relapsing-remitting multiple sclerosis. Considering also the convenience of the oral administration, and the low cost for health service providers, azathioprine may represent an alternative to interferon treatment, while the different side effect profiles of both medications have to be taken into account.

Trial Registration

EudraCT 2006-004937-13  相似文献   
127.
128.
East Africa (EA) has witnessed pivotal steps in the history of human evolution. Due to its high environmental and cultural variability, and to the long‐term human presence there, the genetic structure of modern EA populations is one of the most complicated puzzles in human diversity worldwide. Similarly, the widespread Afro‐Asiatic (AA) linguistic phylum reaches its highest levels of internal differentiation in EA. To disentangle this complex ethno‐linguistic pattern, we studied mtDNA variability in 1,671 individuals (452 of which were newly typed) from 30 EA populations and compared our data with those from 40 populations (2970 individuals) from Central and Northern Africa and the Levant, affiliated to the AA phylum. The genetic structure of the studied populations—explored using spatial Principal Component Analysis and Model‐based clustering—turned out to be composed of four clusters, each with different geographic distribution and/or linguistic affiliation, and signaling different population events in the history of the region. One cluster is widespread in Ethiopia, where it is associated with different AA‐speaking populations, and shows shared ancestry with Semitic‐speaking groups from Yemen and Egypt and AA‐Chadic‐speaking groups from Central Africa. Two clusters included populations from Southern Ethiopia, Kenya and Tanzania. Despite high and recent gene‐flow (Bantu, Nilo‐Saharan pastoralists), one of them is associated with a more ancient AA‐Cushitic stratum. Most North‐African and Levantine populations (AA‐Berber, AA‐Semitic) were grouped in a fourth and more differentiated cluster. We therefore conclude that EA genetic variability, although heavily influenced by migration processes, conserves traces of more ancient strata. Am J Phys Anthropol, 2013. © 2013 Wiley Periodicals, Inc.  相似文献   
129.
Zunino  Serena  Libralato  Simone  Melaku Canu  Donata  Prato  Giulia  Solidoro  Cosimo 《Ecosystems》2021,24(7):1561-1575
Ecosystems - Ocean acidification (OA) is expected to impact habitat-forming species (HFS), with cascading effects on the whole marine ecosystem and related services that are seldom quantified....  相似文献   
130.
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