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991.
In iron-limited medium, a siderophore producing soil isolate ofAzotobacter chroococcum showed a high level of hydroxamate with relatively low level of nitrogen fixation. Inclusion of iron in the medium resulted
in increased nitrogen fixation with decreased hydroxamate production. Under shake culture conditions, the level of both hydroxamate
and catechol type of siderophores decreased after 2 d of incubation in iron-deficient medium. However, under iron-sufficient
conditions, both siderophore production and nitrogen fixation increased with time although the level of siderophore was quite
low. A number of soil isolates and mutants ofA. chrococcum were tested for nitrogen fixation, hydroxamate and catechol type of siderophore production. Wide variation was observed in
the siderophore level and nitrogen fixation in the cultures tested. Nitrogen fixation was higher in the iron-sufficient medium
than in iron-limited one while hydroxamate yield was higher in iron-limited medium than in the iron-sufficient one in all
the cultures. Inclusion of ammonium acetate in the medium induced catechol synthesis in more than 60% of the cultures. 相似文献
992.
Coline C. F. Boonman Ana Benítez‐Lpez Aafke M. Schipper Wilfried Thuiller Madhur Anand Bruno E. L. Cerabolini Johannes H. C. Cornelissen Andres Gonzalez‐Melo Wesley N. Hattingh Pedro Higuchi Daniel C. Laughlin Vladimir G. Onipchenko Josep Peuelas Lourens Poorter Nadejda A. Soudzilovskaia Mark A. J. Huijbregts Luca Santini 《Global Ecology and Biogeography》2020,29(6):1034-1051
993.
Background
Exosomes are endosome-derived vesicles that are released when multi-vesicular bodies (MVBs) fuse with the plasma membrane. Exosomes released from mycobacteria-infected cells have recently been shown to be pro-inflammatory. A prominent host molecule that is found within these exosomes is Hsp70, a member of the heat-shock family of proteins.Methodology/Principal Findings
We first characterized the exosomes purified from control and mycobacteria-infected cells. We found that relative to uninfected cells, macrophages infected with M. smegmatis and M. avium release more exosomes and the exosomes they released had more Hsp70 on their surface. Both exosomes and exogenous Hsp70 treatment of macrophages led to NF-κB activation and TNFα release in uninfected macrophages; Hsp70 levels were elevated in mycobacteria-infected cells. Macrophage treatment with Hsp70 also led to increase in the phagocytosis and maturation of latex-bead phagosomes. Finally, Hsp70 pre-incubation of M. smegmatis- and M. avium-infected cells led to increased phago-lysosome fusion, as well as more killing of mycobacteria within macrophages.Conclusions/Significance
Our results fit into an emerging concept whereby exosomes-containing Hsp70 are effective inducers of inflammation, also in response to mycobacterial infection. 相似文献994.
We describe a web-based resource to identify, search and analyze sequence patterns conserved in the multiple sequence alignments of orthologous promoters from closely related / distant Saccharomyces spp. The webtool interfaces with a database where conserved sequence patterns (greater than 4 bp) have been previously extracted from genome-wide promoter alignments, allowing one to carry out user-defined genome-wide searches for conserved sequences to assist in the discovery of novel promoter elements based on comparative genomics. The web-based server can be accessed at http://www2.imtech.res.in/ anand/sacch_prom_pat.html. 相似文献
995.
S. Sumi Surya Ramachandran V RamanKutty Maulin M. Patel T. N. Anand Ajit S Mullasari C. C. Kartha 《Molecular and cellular biochemistry》2017,428(1-2):67-77
Resveratrol is a dietary polyphenol that displays neuroprotective properties in several in vivo and in vitro experimental models, by modulating oxidative and inflammatory responses. Glutathione (GSH) is a key antioxidant in the central nervous system (CNS) that modulates several cellular processes, and its depletion is associated with oxidative stress and inflammation. Therefore, this study sought to investigate the protective effects of resveratrol against GSH depletion pharmacologically induced by buthionine sulfoximine (BSO) in C6 astroglial cells, as well as its underlying cellular mechanisms. BSO exposure resulted in several detrimental effects, decreasing glutamate-cysteine ligase (GCL) activity, cystine uptake, GSH intracellular content and the activities of the antioxidant enzymes glutathione peroxidase (GPx) and glutathione reductase (GR). Moreover, BSO increased reactive oxygen/nitrogen species (ROS/RNS) levels and pro-inflammatory cytokine release. Resveratrol prevented these effects by protecting astroglial cells against BSO-induced cytotoxicity, by modulating oxidative and inflammatory responses. Additionally, we observed that pharmacological inhibition of heme oxygenase 1 (HO-1), an essential cellular defense against oxidative and inflammatory injuries, abolished all the protective effects of resveratrol. These observations suggest HO-1 pathway as a cellular effector in the mechanism by which resveratrol protects astroglial cells against GSH depletion, a condition that may be associated to neurodegenerative diseases. 相似文献
996.
Anand Sarabhai Hildegard Lamfrom 《Biochemical and biophysical research communications》1980,92(2):424-430
An extract, prepared from the germinal vesicles of oocytes, was capable of transcribing cloned T4 tRNA genes. The major product was identified as tRNASer, with some extra nucleotides from neighboring sequences in the tRNA cluster at both termini. 相似文献
997.
Madhan Jeyaraman Albin John Santhosh Koshy Rajni Ranjan Talagavadi Channaiah Anudeep Rashmi Jain Kumari Swati Niraj Kumar Jha Ankur Sharma Kavindra Kumar Kesari Anand Prakash Parma Nand Saurabh Kumar Jha P. Hemachandra Reddy 《生物化学与生物物理学报:疾病的分子基础》2021,1867(2):166014
The coronavirus disease 2019 (COVID-19) has been threatening the globe since the end of November 2019. The disease revealed cracks in the health care system as health care providers across the world were left without guidelines on definitive usage of pharmaceutical agents or vaccines. The World Health Organization (WHO) declared COVID-19 as a pandemic on the 11th of March 2020. Individuals with underlying systemic disorders have reported complications, such as cytokine storms, when infected with the virus. As the number of positive cases and the death toll across the globe continue to rise, various researchers have turned to cell based therapy using stem cells to combat COVID-19. The field of stem cells and regenerative medicine has provided a paradigm shift in treating a disease with minimally invasive techniques that provides maximal clinical and functional outcome for patients. With the available evidence of immunomodulatory and immune-privilege actions, mesenchymal stem cells (MSCs) can repair, regenerate and remodulate the native homeostasis of pulmonary parenchyma with improved pulmonary compliance. This article revolves around the usage of novel MSCs therapy for combating COVID-19. 相似文献
998.
999.
Amrisha Vaish Caroline M. Kelsey Anand Tripathi Tobias Grossmann 《Evolution and human behavior》2017,38(6):729-733
Eyes play a vital role in human social interactions. In fact, some prior work indicates that simply the presence of eyes or eye-like stimuli increases people's prosocial behavior, arguably because the eyes serve as cues of being watched and thus elicit reputational concerns. The current study was designed to address two questions in this regard. First, we examined how salient the eyes are among the human features. Second, we asked whether individual differences in attentiveness to eyes (but not other human features such as ears or hands) are predictive of reputation-enhancing behavior. Using an eye-tracking paradigm, we found that participants looked longest to eyes compared to other human features. Critically, greater attentiveness to eyes correlated with greater generosity on a donation task, but only in a reputation-relevant context (i.e., when donations were public but not when they were anonymous). Attentiveness to other human features did not predict donation behavior. Eyes are thus an especially salient human feature, and attentiveness to eyes may signal individuals' concerns about their reputations. 相似文献
1000.