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131.
One goal of vaccination is to promote development of mucosal effector cells that can immediately respond to peripheral infection. This is especially important for protection against viruses that enter the host through the respiratory tract. We show that targeting the OX40 costimulatory receptor (CD134) strongly promotes mucosal memory in the CD8 T cell compartment. Systemic injection of an agonist antibody to OX40 strongly enhanced development of polyfunctional effector CD8 T cells that were induced after intraperitoneal infection with a highly virulent strain of vaccinia virus. These cells were located in lymphoid organs and also the lung, and importantly, long-term memory CD8 T cells were maintained in the lung over 1 year. Anti-OX40 also boosted memory development when mice were vaccinated subcutaneously with viral peptide. These CD8 T cells were sufficient to provide protection from lethal respiratory infection with live vaccinia virus independent of CD4 T cells and antibody. Again, the CD8 T cell populations that were induced after secondary infection displayed polyfunctionality and were maintained in the lung for over a year. These data suggest that agonists to the OX40 costimulatory receptor represent potential candidates for incorporation into vaccines for respiratory viruses. 相似文献
132.
The aim of this study was to assess the cytotoxic effects of various concentrations of miltefosine on Leishmania major (MRHO/IR/75/ER) and L. tropica (MHOM/IR/02/Mash10) promastigotes and to observe the programmed cell death features. The colorimetric MTT assay was used to find L. major and L. tropica viability and the obtained results were expressed as 50% inhibitory concentration (IC50). Also, 50% effective doses (ED50) for L. major and L. tropica amastigotes were also determined. Annexin-V FLUOS staining was performed to study the cell death properties of miltefosine using FACS analysis. Qualitative analysis of the total genomic DNA fragmentation was performed by agarose gel electrophoresis. Furthermore, to observe changes in cell morphology, promastigotes were examined using light microscopy. In both strains of L. major and L. tropica, miltefosine induced dose-dependent death with features of apoptosis, including cell shrinkage, DNA laddering, and externalization of phosphatidylserine. The IC50 was achieved at 22 μM and 11 μM for L. major and L. tropica after 48 hr of incubation, respectively. ED50 of L. major and L. tropica amastigotes were 5.7 μM and 4.2 μM, respectively. Our results indicate that miltefosine induces apoptosis of the causative agent of cutaneous leishmaniasis in a dose-dependent manner. Interestingly, L. major did not display any apoptotic changes when it was exposed to miltefosine in concentrations sufficient to kill L. tropica. 相似文献
133.
Solaymani-Mohammadi S Singer SM 《Journal of immunology (Baltimore, Md. : 1950)》2011,187(7):3769-3775
Infection or other inflammatory insults in the small intestine often result in reduced disaccharidase enzyme levels. Using a mouse model of giardiasis, we examined the role of host immunity and pathogen virulence in mediating disaccharidase deficiency postinfection (p.i.). C57BL/6J mice were infected with two strains, WB and GS, of the human parasite Giardia duodenalis. The levels of sucrase, maltase, and lactase decreased in wild-type mice p.i. with the GS strain but not with the WB strain. Both CD4-deficient and SCID mice failed to eliminate the infection and did not exhibit disaccharidase deficiency. β(2)-Microglobulin knockout animals controlled infections similar to wild-type mice but exhibited no decrease in disaccharidase activity. Analysis of cytokine production by spleen and mesenteric lymph node cells showed production of IL-4, IL-10, IL-13, IL-17, IL-22, TNF-α, and IFN-γ p.i. with both WB and GS, with IFN-γ being the dominant cytokine for both parasite strains. Mesenteric lymph node cells produced lower levels of cytokines compared with splenocytes in response to parasite extract, although the overall pattern was similar. These data suggest that T cell responses mediate parasite clearance whereas also contributing to pathogenesis. They also demonstrate that differences in pathogen strain can also determine the outcome of infection and further our understanding of the clinical variation seen in human giardiasis. 相似文献
134.
Wong RP Lin H Khosravi S Piche B Jafarnejad SM Chen DW Li G 《Nucleic acids research》2011,39(9):3632-3642
The lesion bypass pathway, which is regulated by monoubiquitination of proliferating cell nuclear antigen (PCNA), is essential for resolving replication stalling due to DNA lesions. This process is important for preventing genomic instability and cancer development. Previously, it was shown that cells deficient in tumour suppressor p33ING1 (ING1b) are hypersensitive to DNA damaging agents via unknown mechanism. In this study, we demonstrated a novel tumour suppressive function of ING1b in preserving genomic stability upon replication stress through regulating PCNA monoubiquitination. We found that ING1b knockdown cells are more sensitive to UV due to defects in recovering from UV-induced replication blockage, leading to enhanced genomic instability. We revealed that ING1b is required for the E3 ligase Rad18-mediated PCNA monoubiquitination in lesion bypass. Interestingly, ING1b-mediated PCNA monoubiquitination is associated with the regulation of histone H4 acetylation. Results indicate that chromatin remodelling contributes to the stabilization of stalled replication fork and to the regulation of PCNA monoubiquitination during lesion bypass. 相似文献
135.
Molla Kazemiha V Azari S Amanzadeh A Bonakdar S Shojaei Moghadam M Habibi Anbouhi M Maleki S Ahmadi N Mousavi T Shokrgozar MA 《Cytotechnology》2011,63(6):609-620
Mycoplasma contamination is a deleterious event for cell culture laboratories. Plasmocin™ is used to prevent and eradicate
mycoplasma infections from cell. In this study, 80 different mammalian cell lines from various sources; human, monkey, mice,
hamster and rat were used to study and evaluate plasmocin™ efficiency and compare it to commonly used antibiotics such as
BM-cyclin, ciprofloxacin and mycoplasma removal agent (MRA). It was shown that mycoplasma infections were eradicated by plasmocin™,
BM-cyclin, ciprofloxacin and MRA in 65%, 66.25%, 20%, and 31.25%, respectively, of infected cell cultures. However, re-infection
with mycoplasmas after the period of 4 months occurred in 10–80% of the studied cell lines. Cell cytotoxicity and culture
death was observed in 25, 17.5 and 10% of the treated cells, for plasmocin™, BM-cyclin and MRA, respectively. In this study,
Plasmocin™ showed strong ability to eradicate mollicutes from our cell lines with minimal percentage of regrowth. However,
due to its high cell cytotoxicity it should be used with caution especially when dealing with expensive or hard-to-obtain
cell lines. Amongst the antibiotics tested, BM-cyclin was shown to remove mycoplasma with the highest efficiency. 相似文献
136.
Aboutalebian Shima Mahmoudi Shahram Okhovat Ahmadreza Khodavaisy Sadegh Mirhendi Hossein 《Mycopathologia》2020,185(3):569-575
Mycopathologia - Otomycosis is a common finding in otorhinolaryngology clinics and is usually caused by species of Candida and Aspergillus, particularly black aspergilli. Meanwhile, other fungi can... 相似文献
137.
Hassan Karimmojeni Amir Hossein Bazrafshan Mohammad Mehdi Majidi Shahram Torabian Behzad Rashidi 《Plant Species Biology》2014,29(3):E1-E8
Amaranthus retroflexus L. is an importunate annual weed in many cropping systems of different countries. The main aim of this study was to investigate the effects of maternal nitrogen and drought stress on the seed dormancy and germinability of A. retroflexus. Field experiment was carried out in a factorial based on randomized complete block design, with four potential levels of soil water (–2, ?6, ?8 and ?10 bar) and three levels of nitrogen (0, 100 and 200 kg/ha). The germination characteristics of the seeds were measured at three different times (1 month, 6 months and 1 year after harvesting). Results showed that drought stress had positive effects on breaking of A. retroflexus seed dormancy until 6 months after seed harvesting. Seeds that were developed under severe water stress exhibited the highest germination percentage and germination rate. The results obtained from this study revealed that application of 100 kg/ha nitrogen during seed development increases germinability of A. retroflexus, whereas application of 200 kg/ha nitrogen induced seed dormancy. Furthermore, 100 kg/ha nitrogen application in the field along with 200 ppm gibberellic‐acid treatment during seed after‐ripening showed the highest germination percentage and germination rate for seeds after 6 months harvesting. Results also indicated that after‐ripening significantly increased seed germination and germination rate of A. retroflexus. These findings indicate that long‐term management of the soil seed bank in this species requires more stringent control due to the changes in germination timing, as detected in this study. 相似文献
138.
Shahram Jevin Poureetezadi Eric K. Donahue Rebecca A. Wingert 《Journal of visualized experiments : JoVE》2014,(93)
Zebrafish have become a widely used model organism to investigate the mechanisms that underlie developmental biology and to study human disease pathology due to their considerable degree of genetic conservation with humans. Chemical genetics entails testing the effect that small molecules have on a biological process and is becoming a popular translational research method to identify therapeutic compounds. Zebrafish are specifically appealing to use for chemical genetics because of their ability to produce large clutches of transparent embryos, which are externally fertilized. Furthermore, zebrafish embryos can be easily drug treated by the simple addition of a compound to the embryo media. Using whole-mount in situ hybridization (WISH), mRNA expression can be clearly visualized within zebrafish embryos. Together, using chemical genetics and WISH, the zebrafish becomes a potent whole organism context in which to determine the cellular and physiological effects of small molecules. Innovative advances have been made in technologies that utilize machine-based screening procedures, however for many labs such options are not accessible or remain cost-prohibitive. The protocol described here explains how to execute a manual high-throughput chemical genetic screen that requires basic resources and can be accomplished by a single individual or small team in an efficient period of time. Thus, this protocol provides a feasible strategy that can be implemented by research groups to perform chemical genetics in zebrafish, which can be useful for gaining fundamental insights into developmental processes, disease mechanisms, and to identify novel compounds and signaling pathways that have medically relevant applications. 相似文献
139.
Mirkhani V Tangestaninejad S Moghadam M Karimian Z 《Bioorganic & medicinal chemistry letters》2003,13(20):3433-3435
Oxidative decarboxylation of carboxylic acids by a supported manganese (III) porphyrin was investigated. In the chemical system using 5,10,15,20-tetrakis(4-aminophenyl)porphyrinatomanganese (III) chloride supported on crosslinked chloromethylated polystyrene, [Mn(H(2)NTPP)-CMP], as catalyst, carboxylic acids are converted to the corresponding carbonyl compounds via oxidative decarboxylation with sodium periodate. 相似文献
140.
Shahram Rafieian 《Biosemiotics》2012,5(1):83-93
A human being is the simultaneous composite of several different levels of being, from atomic and subatomic to the level of
complex social interaction, and these levels are nested within the individual hierarchically (lower levels giving rise to
higher levels, etc.). One of the most important and influential approaches developed in the history of science has been that
of systems theory and systemic thinking, in which the different levels of the hierarchy, and the interactions between those
levels, are considered simultaneously. Although this model provides a comprehensive view of biological being, the transition
from one level to the other is not well defined in it. Uexküll and Pauli (Advances: Journal of the Institute for 417 the Advancement
of Health 3:158–174, 1986) suggested that semiosis is the translator of the events from one level to the other. From a psychological point of view, a myriad of semiotic events
happen inside an individual, and it has been suggested that among other semiotic events, inner speech plays an important role in mediating personal agency. Dialogical theories of the self, Jungian psychology and hypnosis research evidence show that there is a semiotic multiplicity
in human agency and consciousness, and that these multiple streams are all converge to a central semiotic singularity. I argue
in this paper that by taking a biosemiotic point of view, human ‘agency’ may be defined as the ability of an individual to
direct the incoming and internal streams of semioses and the ability to create an integrative and superordinate new stream
of semiosis in addition to the upwardly and downwardly component ones, and how such a view might open a new door for research
into the concept of human ‘personality’ and ‘agency’. 相似文献