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221.
222.
Shankargouda Patil Heba Ashi Jagadish Hosmani Abdulrahman Yahya Almalki Yaser Ali Alhazmi Shazia Mushtaq Sameena Parveen Hosam Ali Baeshen Saranya Varadarajan A. Thirumal Raj Vikrant R. Patil Nishant Vyas 《Saudi Journal of Biological Sciences》2021,28(8):4553-4559
BackgroundTinospora cordifolia (Thunb.) Miers (Giloy) has been applied successfully as an anti-inflammatory, anti-diabetic, and even as an anti-cancer agent. Yet, to date, the application of Giloy has not been explored concerning oral cancer.ObjectivesTo assess the effect of T cordifolia (Thunb.) Miers (Giloy) extract (TcE) on an oral cancer cell line.MethodsAW13516 (oral cancer cell line) cells were treated with the prepared aqueous extract of TcE for 24 h at various concentrations ranging between 5 μg/ml and 100 μg/ml and compared with control (cells without treatment). Thee effect of the extracts on apoptosis was assessed by through Annexin V flow cytometry assay and Luminometry based assessment of Caspase 8, 9 and caspase 3/7 activity. RNA was isolated from treated cells and gene expression of selected metastatic genes (MMP1, MMP10, and CXCL8); epithelial-mesenchymal stem cell genes (TWIST1, SNAIL, ZEB1, Oct4) and stemness related genses (Nanog, Sox2) were analyzed by using a quantitative real-time PCR system. The experiments were performed in triplicates.ResultsAqueous extract of TcE was found to induce apoptosis inducer in AW13516 cells in a concentration-dependent manner and was potent even at a low concentration of 5 μg/ml. The apoptosis induction was confirmed with the caspase activity assay. Treatment of the cells with the extract for 24 h exhibited a significant decrease in the expression of EMT genes in a dose-dependent manner without an effect on the metastatic genes.ConclusionAqueous extract of TcE induces apoptosis-mediated cell death in the oral cancer cell line AW13516 while attenuating its potential for epithelial mesenchymal transition. 相似文献
223.
Hydrogenophaga sp. strain PBC is an effective degrader of 4-aminobenzenesulfonate isolated from textile wastewater. Here we present the assembly and annotation of its genome, which may provide further insights into its metabolic potential. This is the first announcement of the draft genome sequence of a strain from the genus Hydrogenophaga. 相似文献
224.
Enzymatic synthesis of palm-based ascorbyl esters 总被引:2,自引:0,他引:2
Hamidah Burham Raizatul Ainaa Gafoor Abdul Rasheed Noorullhamezon Md. Noor Suzaini Badruddin Hamidah Sidek 《Journal of Molecular Catalysis .B, Enzymatic》2009,58(1-4):153-157
The synthesis of palm-based ascorbyl esters through transesterification of ascorbic acid and palm oil in tert-amyl alcohol catalyzed by immobilized lipase is described. Highest conversion (70–75%) was determined after 16 h reaction at 40 °C using lipase (Novozyme 435 from Candida antartica) with an ascorbic acid to palm oil mole ratio of 1:8. The purified product was further characterized by 13C NMR and GC–MS and the mixture of ascorbyl monoesters obtained were identified as ascorbyl monooleate (61%), ascorbyl monopalmitate (30%) and ascorbyl monostearate (9%). The antioxidant activity of palm-based ascorbyl esters was evaluated by 1,1-diphenyl-2-picrylhydrazyl (DPPH) test. The results showed that pure palm-based ascorbyl esters have an antioxidant activity with an IC50 value of 0.1 mg/mL. 相似文献
225.
Oliver J. Sabot Alex Mwita Justin M. Cohen Yahya Ipuge Megumi Gordon David Bishop Moses Odhiambo Lorrayne Ward Catherine Goodman 《PloS one》2009,4(9)
Background
WHO estimates that only 3% of fever patients use recommended artemisinin-based combination therapies (ACTs), partly reflecting their high prices in the retail sector from where many patients seek treatment. To overcome this challenge, a global ACT subsidy has been proposed. We tested this proposal through a pilot program in rural Tanzania.Methods/Principal Findings
Three districts were assigned to serve either as a control or to receive the subsidy plus a package of supporting interventions. From October 2007, ACTs were sold at a 90% subsidy through the normal private supply chain to intervention district drug shops. Data were collected at baseline and during intervention using interviews with drug shop customers, retail audits, mystery shoppers, and audits of public and NGO facilities.The proportion of consumers in the intervention districts purchasing ACTs rose from 1% at baseline to 44.2% one year later (p<0.001), and was significantly higher among consumers purchasing for children under 5 than for adults (p = 0.005). No change in ACT usage was observed in the control district. Consumers paid a mean price of $0.58 for ACTs, which did not differ significantly from the price paid for sulphadoxine-pyrimethamine, the most common alternative. Drug shops in population centers were significantly more likely to stock ACTs than those in more remote areas (p<0.001).Conclusions
A subsidy introduced at the top of the private sector supply chain can significantly increase usage of ACTs and reduce their retail price to the level of common monotherapies. Additional interventions may be needed to ensure access to ACTs in remote areas and for poorer individuals who appear to seek treatment at drug shops less frequently.Trial Registration
Controlled-Trials.com ISRCTN39125414. 相似文献226.
Intratumoral Delivery of Paclitaxel in Solid Tumor from Biodegradable Hyaluronan Nanoparticle Formulations 总被引:1,自引:0,他引:1
Abeer M. Al-Ghananeem Ahmad H. Malkawi Yahya M. Muammer Justin M. Balko Esther P. Black Walid Mourad Edward Romond 《AAPS PharmSciTech》2009,10(2):410-417
In the current study, novel paclitaxel-loaded cross-linked hyaluronan nanoparticles were engineered for the local delivery
of paclitaxel as a prototype drug for cancer therapy. The nanoparticles were prepared using a desolvation method with polymer
cross-linking. In vitro cytotoxicity studies demonstrated that less than 75% of the MDA-MB-231 and ZR-75-1 breast cancer cells were viable after
2-day exposure to paclitaxel-loaded hyaluronan nanoparticles or free paclitaxel, regardless of the dose. These results suggest
that hyaluronan nanoparticles maintain the pharmacological activity of paclitaxel and efficiently deliver it to the cells.
Furthermore, in vivo administration of the drug-loaded nanoparticles via direct intratumoral injection to 7,12-dimethylbenz[a]anthracene (DMBA)-induced
mammary tumor in female rats was studied. The paclitaxel-loaded nanoparticles treated group showed effective inhibition of
tumor growth in all treated rats. Interestingly, there was one case of complete remission of tumor nodule and two cases of
persistent reduction of tumor size that was observed on subsequent days. In the case of free paclitaxel-treated group, the
mean tumor volume increased almost linearly (R
2 = 0.93) with time to a size that was 4.9-fold larger than the baseline volume at 57 days post-drug administration. Intratumoral
administration of paclitaxel-loaded hyaluronan nanoparticles could be a promising treatment modality for solid mammary tumors. 相似文献
227.
Interleukin 10 (IL-10) and interleukin 6 (IL-6) are widely investigated in solid tumors as being important prognostic factors. IL-10 and IL-6 serum levels were measured by enzyme-linked immunosorbent assay from sera taken from 40 non-Hodgkin's lymphoma (NHL) patients before and after treatment and from 20 healthy controls. The patients had been observed for at least 18 months or until death. IL-10 and IL-6 were significantly higher in NHL patients compared to controls. IL-6 was correlated with IL-10 (r = 0.451) and with B symptoms (weight loss > 10% during the last 6 months, unexplained fever and night sweats) (r = 0.447). IL-10 and IL-6 were significantly higher in non survival compared to survival group. High pretreatment IL-10 and IL-6 was associated with poor overall survival. These results show that IL-10 and IL-6 levels are elevated in NHL patients and seem to suggest that simultaneous elevation of IL-10 and IL-6 is a powerful negative prognostic parameter in NHL. 相似文献
228.
Tahboub YR Galijasevic S Diamond MP Abu-Soud HM 《The Journal of biological chemistry》2005,280(28):26129-26136
We investigated the potential role of the co-substrate, thiocyanate (SCN-), in modulating the catalytic activity of myeloperoxidase (MPO) and other members of the mammalian peroxidase superfamily (lactoperoxidase (LPO) and eosinophil peroxidase (EPO)). Pre-incubation of SCN- with MPO generates a more complex biological setting, because SCN- serves as either a substrate or inhibitor, causing diverse impacts on the MPO heme iron microenvironment. Consistent with this hypothesis, the relationship between the association rate constant of nitric oxide binding to MPO-Fe(III) as a function of SCN- concentration is bell-shaped, with a trough comparable with normal SCN- plasma levels. Rapid kinetic measurements indicate that MPO, EPO, and LPO Compound I formation occur at rates slower than complex decay, and its formation serves to simultaneously catalyze SCN- via 1e- and 2e- oxidation pathways. For the three enzymes, Compound II formation is a fundamental feature of catalysis and allows the enzymes to operate at a fraction of their possible maximum activities. MPO and EPO Compound II is relatively stable and decays gradually within minutes to ground state upon H2O2 exhaustion. In contrast, LPO Compound II is unstable and decays within seconds to ground state, suggesting that SCN- may serve as a substrate for Compound II. Compound II formation can be partially or completely prevented by increasing SCN- concentration, depending on the experimental conditions. Collectively, these results illustrate for the first time the potential mechanistic differences of these three enzymes. A modified kinetic model, which incorporates our current findings with the mammalian peroxidases classic cycle, is presented. 相似文献
229.
Yue Ming Chew SiewFen Lye Madihah Md. Salleh Adibah Yahya 《Symbiosis (Philadelphia, Pa.)》2018,76(2):187-197
The termite gut is a highly structured microhabitat with physicochemically distinct regions. It is generally separated into the foregut, midgut and hindgut. The distribution of gut microbiota is greatly influenced by varying physicochemical conditions within the gut. Thus, each gut compartment has a unique microbial population structure. In this study, the bacterial communities of foregut, midgut and hindgut of wood-feeding higher termite, Bulbitermes sp. were analyzed in detail via metagenomic sequencing of the 16S rRNA V3-V4 region. While the microbiomes of the foregut and midgut shared a similar taxonomic pattern, the hindgut possessed more diverse bacterial phylotypes. The communities in the foregut and midgut were dominated by members of the group Bacilli and Clostridia (Firmicutes) as well as taxon Actinomycetales (Actinobacteria). The main bacterial lineage found in hindgut was Spirochaetaceae (Spirochaetes). The significant difference among the three guts was the relative abundance of the potential lignin-degrading bacteria, Actinomycetales, in both the foregut and midgut. This suggests that lignin modification was probably held in the anterior part of termite gut. Predictive functional profiles of the metagenomes using 16S rRNA marker gene showed that cell motility, energy metabolism and metabolism of cofactors and vitamins were found predominantly in hindgut microbiota, whereas xenobiotics degradation and metabolism mostly occurred in the foregut segment. This was compatible with our 16S rRNA metagenomic results showing that the lignocellulose degradation process was initiated by lignin disruption, increasing the accessibility of celluloses and hemicelluloses. 相似文献
230.
Ehsaneh Azaryan Fariba Emadian Razavi Mohammad Yahya Hanafi-Bojd Esmat Alemzadeh Mohsen Naseri 《Biotechnology progress》2023,39(2):e3319
Missing or damaged teeth due to caries, genetic disorders, oral cancer, or infection may contribute to physical and mental impairment that reduces the quality of life. Despite major progress in dental tissue repair and those replacing missing teeth with prostheses, clinical treatments are not yet entirely satisfactory, as they do not regenerate tissues with natural teeth features. Therefore, much of the focus has centered on tissue engineering (TE) based on dental stem/progenitor cells to create bioengineered dental tissues. Many in vitro and in vivo studies have shown the use of cells in regenerating sections of a tooth or a whole tooth. Tooth tissue engineering (TTE), as a promising method for dental tissue regeneration, can form durable biological substitutes for soft and mineralized dental tissues. The cell-based TE approach, which directly seeds cells and bioactive components onto the biodegradable scaffolds, is currently the most potential method. Three essential components of this strategy are cells, scaffolds, and growth factors (GFs). This study investigates dentin regeneration after an injury such as caries using TE and stem/progenitor cell-based strategies. We begin by discussing about the biological structure of a dentin and dentinogenesis. The engineering of teeth requires knowledge of the processes that underlie the growth of an organ or tissue. Then, the three fundamental requirements for dentin regeneration, namely cell sources, GFs, and scaffolds are covered in the current study, which may ultimately lead to new insights in this field. 相似文献