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101.
Srivatsava Anshuman Mittal Deepika Govindasamy Sharmila Chandrasekaran Muthukumaran 《Journal of Genetic Engineering and Biotechnology》2013,11(1):33-37
Nostoc ellipsosporum is a highly potent cyanobacterium for production of pharmaceutically important chemicals. In this study, an effort has been made to determine the effect of glucose and phytohaemagglutinin (PHA) rich Phaseolus vulgaris extract on N. ellipsosporum growth and protein production. Maximum growth was observed in Fog’s medium supplemented with glucose. SEM analysis showed that the regular and well developed heterocysts were observed in Fog’s media supplemented with glucose. Significant medium components were evaluated by Plackett–Burman (PB) design and PHA extract was found to be the most significant in growth medium. Results of this study showed that both glucose and PHA rich P. vulgaris extract have positive effects and enhance the growth and protein synthesis. 相似文献
102.
We discovered that Yeast Extract Mannitol (YEM) medium possessed immense potential to generate silver nanoparticles from AgNO3 upon autoclaving, which was evident from (i) alteration in color of the medium; (ii) peak at ∼410 nm in UV-Vis spectrum due to surface plasmon resonance specific to silver nanoparticles; and (iii) TEM investigations. TEM coupled with EDX confirmed that distinct nanoparticles were composed of silver. Yeast extract and mannitol were key components of YEM medium responsible for the formation of nanoparticles. PXRD analysis indicated crystalline geometry and Ag/Ag2O phases in nanoparticles generated with YEM medium, yeast extract and mannitol. Our investigations also revealed that both mannitol and yeast extract possessed potential to convert ∼80% of silver ions in 0.5 mM AgNO3 to nanoparticles, on autoclaving for 30 min at 121°C under a pressure of 1.06 kg/cm2. Addition of filter sterilized AgNO3 under ambient conditions to pre-autoclaved YEM medium and yeast extract brought about color change due to the formation of silver nanoparticles, but required prolonged duration. In general, even after 72 h intensity of color was significantly less than that recorded following autoclaving. Silver nanoparticles formed at room temperature were more heterogeneous compared to that obtained upon autoclaving. In summary, our findings demonstrated that (i) YEM medium and its constituents promote synthesis of silver nanoparticles; and (ii) autoclaving enhances rapid synthesis of silver nanoparticles by YEM medium, yeast extract and mannitol. 相似文献
103.
Paramita Mandal Bornali Bhattacharjee Damayanti Das Ghosh Nidhu Ranjan Mondal Rahul Roy Chowdhury Sudipta Roy Sharmila Sengupta 《PloS one》2013,8(6)
We tested the hypothesis that (i) synonymous variations within the coding regions, and (ii) variations within the non-coding regions of HPV, influence cervical cancer (CaCx) pathogenesis under the impact of intact HPV16 genomes. Whole genome sequence analysis of HPV16 isolates within 70 CaCx cases and 25 non-malignant samples revealed that synonymous variations were significantly higher within the E6 (p = 0.014), E5 (p = 0.001) and L2 (p = 0.0002) genes of HPV16 isolates within cases, compared to isolates within non-malignant samples. All of the 25 (100%) humanized codons identified within L2 ORF of the samples analyzed, were harbored by CaCx cases, while 8 out of 25 (32%) were harbored by HPV16 positive non-malignant samples (p = 3.87105E-07). L2 (mRNA and protein) expression was evident only among cases with episomal viral genomes and L2 mRNA expression correlated significantly with E2 gene copy numbers suggesting expression from all episomal genomes. Among such cases, Asian American (AA) isolates portrayed all of the humanized codons (100%; 4–6/sample) recorded within L2, which was significantly higher (p = 2.02E-7) compared to the European (E) isolates (22.8%; none or 1–2/sample). Additionally, majority of E variant isolates within cases (54/57; 94.7%) portrayed a variation (T4228C) within the short non-coding region (NCR2) between E5 and L2 genes, which portrays a weak promoter activity specific for L2 mRNA expression. This resulted in loss of 9 out of 14 miRNA binding sites (hsa-miR-548 family), despite the significant overexpression of miR548a-5p and miR548d-5p among such cases (28.64 and 36.25 folds, respectively), in comparison to HPV negative control samples. The findings exemplify the biological relevance of sequence variations in HPV16 genomes and highlight that episomal HPV16 in CaCx cases employ multiple mechanisms to sustain L2 expression, thereby justifying the potential role of L2 in such cancers, as opposed to those harboring viral integration. 相似文献
104.
Senthilkumar K Arunkumar R Elumalai P Sharmila G Gunadharini DN Banudevi S Krishnamoorthy G Benson CS Arunakaran J 《Cell biochemistry and function》2011,29(2):87-95
Urokinase-type plasminogen activator (uPA) is a serine protease that is involved in cancer progression, especially invasion and metastasis including prostate cancer. uPA activation is mediated by transactivation of uPAR and epidermal growth factor receptor (EGF-R) in prostate cancer progression. Prostate cancer (PC-3) cells have highly invasive capacity and they express uPA and uPAR gene. PC-3 cells are treated with quercetin, which inhibits invasion and migration of PC-3 cells. Quercetin downregulates uPA, uPAR and EGF, EGF-R mRNA expressions. Quercetin inhibits cell survival factor β-catenin, NF-κB and also proliferative signalling molecules such as p-EGF-R, N-Ras, Raf-1, c.Fos c.Jun and p-c.Jun protein expressions. But quercetin increased p38 mitogen-activated protein kinase protein expression. Our results suggest that quercetin inhibit migration and invasion of prostate cancer cells. It shows the value for treatment of invasive and metastasis type of prostate cancer. 相似文献
105.
Kakwani MD Suryavanshi P Ray M Rajan MG Majee S Samad A Devarajan P Degani MS 《Bioorganic & medicinal chemistry letters》2011,21(7):1997-1999
A series of cinnamide derivatives was designed as potential antimycobacterial agents using molecular hybridization approach. The diamine moiety, a key feature of ethambutol and its other analogs, and certain structural features of cerulenin and cinnamic acid were hybridized to obtain cinnamide derivatives. The minimum inhibitory concentration (MIC) of all synthesized compounds was determined against M. tuberculosis H37Rv using Resazurin Microtitre plate Assay (REMA) method. The synthesized molecules showed good to moderate activity with MIC in the range of 5-150 μM and good safety profile. Additionally, the most potent compound 1a, having MIC 5.1 μM exhibited synergy with rifampicin. 相似文献
106.
Rane S 《Indian journal of microbiology》2011,51(1):100-106
Street food vending has become an important public health issue and a great concern to everybody. This is due to widespread
food borne diseases, due to the mushrooming of wayside food vendors who lack an adequate understanding of the basic food safety
issues. Major sources contributing to microbial contamination are the place of preparation, utensils for cooking and serving,
raw materials, time and temperature abuse of cooked foods and the personal hygiene of vendors. Various studies have identified
the sources of food safety issues involved in street foods to be microorganism belonging to the genus Bacillus, Staphylococcus, Clostridium, Vibrio, Campylobacter, Listeria, Salmonella. Application of sound risk analysis policies is being advocated to provide a scientific base to the host of risk management
option which India may need to explore to ensure public health and safety. 相似文献
107.
The elaborate networks and the crosstalk of established signaling molecules like salicylic acid (SA), jasmonic acid (JA),
ethylene (ET), abscisic acid (ABA), reactive oxygen species (ROS) and glutathione (GSH) play key role in plant defense response.
To obtain further insight into the mechanism through which GSH is involved in this crosstalk to mitigate biotic stress, transgenic
Nicotiana tabacum overexpressing Lycopersicon esculentum gamma-glutamylcysteine synthetase (LeECS) gene (NtGB lines) were generated with enhanced level of GSH in comparison with wild-type plants exhibiting resistance to pathogenesis
as well. The expression levels of non-expressor of pathogenesis-related genes 1 (NPR1)-dependent genes like pathogenesis-related
gene 1 (NtPR1), mitogen-activated protein kinase kinase (NtMAPKK), glutamine synthetase (NtGLS) were significantly enhanced alongwith NtNPR1. However, the expression levels of NPR1-independent genes like NtPR2, NtPR5 and short-chain dehydrogenase/reductase family protein (NtSDRLP) were either insignificant or were downregulated. Additionally, increase in expression of thioredoxin (NtTRXh), S-nitrosoglutathione reductase 1 (NtGSNOR1) and suppression of isochorismate synthase 1 (NtICS1) was noted. Comprehensive analysis of GSH-fed tobacco BY2 cell line in a time-dependent manner reciprocated the in planta results. Better tolerance of NtGB lines against biotrophic Pseudomonas syringae pv. tabaci was noted as compared to necrotrophic Alternaria alternata. Through two-dimensional gel electrophoresis (2-DE) and image analysis, 48 differentially expressed spots were identified
and through identification as well as functional categorization, ten proteins were found to be SA-related. Collectively, our
results suggest GSH to be a member in cross-communication with other signaling molecules in mitigating biotic stress likely
through NPR1-dependent SA-mediated pathway. 相似文献
108.
Balch C Nephew KP Huang TH Bapat SA 《BioEssays : news and reviews in molecular, cellular and developmental biology》2007,29(9):842-845
Silencing of tumor suppressor genes (TSGs), by DNA methylation, is well known in adult cancers. However, based on the "stem cell" theory of tumorigenesis, the early epigenetic events arising in malignant precursors remain unknown. A recent report demonstrates that, while pluripotent embryonic stem cells lack DNA methylation and possess a "bivalent" pattern of activating and repressive histone marks in numerous TSGs, analogous multipotent malignant cells derived from germ cell tumors (embryonic carcinoma cells) gain additional silencing modifications to those same genes. These results suggest a possible mechanism by which aberrant differentiation, mediated by histone and DNA methylation, instigates tumor progression. 相似文献
109.
110.