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71.
High pigment1 mutation negatively regulates phototropic signal transduction in tomato seedlings 总被引:4,自引:0,他引:4 下载免费PDF全文
Phototropins and phytochromes are the major photosensory receptors in plants and they regulate distinct photomorphogenic responses. The molecular mechanisms underlying functional interactions of phototropins and phytochromes remain largely unclear. We show that the tomato (Lycopersicon esculentum) phytochrome A deficient mutant fri lacks phototropic curvature to low fluence blue light, indicating requirement for phytochrome A for expression of phototropic response. The hp1 mutant that exhibits hypersensitive responses to blue light and red light reverses the impairment of second-positive phototropic response in tomato in phytochrome A-deficient background. Physiological analyses indicate that HP1 functions as a negative regulator of phototropic signal transduction pathway, which is removed via action of phytochrome A. The loss of HP1 gene product in frihp1 double mutant allows the unhindered operation of phototropic signal transduction chain, obviating the need for the phytochrome action. Our results also indicate that the role of phytochrome in regulating phototropism is restricted to low fluence blue light only, and at high fluence blue light, the phytochrome A-deficient fri mutant shows the normal phototropic response. 相似文献
72.
The chlorophyll (Chl) fluorescence emission as well as excitation and polarization characteristics of chloroplasts from intact cotyledons were determined in pumpkin seedlings after removal of one cotyledon (co-cotyledon) or apical bud or primary root, or after kinetin treatment of derooted seedlings. Qualitatively, the fluorescence emission and excitation spectra of chloroplasts were similar. The fluorescence emission spectra showed a maximum at 685 (F685) and a hump at 735 nm (F735), whereas the excitation spectra showed peaks at 439, 471, 485, and 676 nm. The fluorescence intensities at F685 and F735 differed in various groups of seedlings, as indicated by changes in their ratios. Similarly, the ratios of 471/439, 485/439, and 676/439 nm were also different. Variability in the Chl fluorescence intensity values and the fluorescence polarization of chloroplasts prepared from various seedling types may suggest a different degree of binding between the pigment complexes and light-harvesting Chl-protein (LHCP), resulting in different rates of photoexcitation energy loss in the form of fluorescence emission. Kinetin treatment improved the coupling of pigment complexes with reaction centre, as indicated by low polarization values in derooted and kinetin-treated seedlings, which suggests the development of a suntype chloroplast. 相似文献
73.
Integrated analysis in bi-parental and natural populations reveals CsCLAVATA3 (CsCLV3) underlying carpel number variations in cucumber 总被引:1,自引:0,他引:1
74.
Shweta Lawania Navneet Singh Digambar Behera Siddharth Sharma 《Biochemical genetics》2018,56(4):375-396
The present study investigated the role of Xeroderma pigmentosum group A (XPA) polymorphism (A23G and G709A) with lung cancer risk and its association with overall survival in North Indians. 370 cases and 370 controls were investigated to evaluate association between XPA polymorphism (A23G and G709A) with lung cancer risk using logistic regression analysis. A follow-up study was also conducted for 291 lung cancer cases illustrating correlation between overall survival in lung cancer patients and XPA variants. GG genotype showed an increased lung cancer risk (p = 0.0007) for A23G polymorphism whereas G709A polymorphism was associated with significant protective effect in heterozygous (AG) subjects (p = 0.001). When stratified according to smoking status an increased risk for lung cancer was observed for GG genotype in A23G polymorphism (p = 0.0002). A poor survival in females carrying variant genotype (GG) was observed (p = 0.001; MST = 4.16 months) for A23G polymorphism. Adenocarcinoma patients with heterozygous genotype showed an increased hazard ratio (p = 0.02) for A23G polymorphism. G709A was associated with a reduced hazard ratio marking a better survival among mutant females (HR 0.17; p = 0.05; MST = 18.63 months). It can be concluded that A23G polymorphism might contribute to increased lung cancer risk in North Indian population emphasizing on poor survival among females. G709A polymorphism might result in protective effect in lung cancer subjects. The present study had a low sample size but it could act as reference for the large sample studies in future. 相似文献
75.
Bikash Chandra Behera Rashmi Ranjan Mishra Santosh Kumar Singh Sushil Kumar Dutta 《Biocatalysis and Biotransformation》2016,34(1):44-53
In the present study, two cellulose-degrading bacteria (CDB-5 and CDB-12) were isolated from mangrove soils of Mahanadi river delta, based on halo zone formation in Congo red agar medium and evaluation for cellulase production in CMC broth medium. Based on morphological, biochemical and 16S rRNA gene sequencing, the two strains, CDB-5 and CDB-12, were identified as Brucella sp. and Bacillus licheniformis, respectively. The gene bank accession number of the strains CDB-5 and CDB-12 are KR632646 and KR632645, respectively. The strain Brucella sp. and B. licheniformis showed an enzyme activity of 96.37?U/ml and 98.25?U/ml, respectively, after 72?h of incubation period. Enzyme production was optimized under different growth conditions such as pH, temperature, agitation rate, carbon source, sodium chloride (NaCl), and nitrogen sources. Maximum cellulase production by both the strains was obtained in the same parameter condition such as pH (7.0), rpm (150), and NaCl (2%, w/v) which varies for other parameters. The strain, CDB-5, produced maximum cellulase at 35?°C temperature, maltose as a carbon source, and yeast extract as a nitrogen source where as the strain CDB-12 produces maximum cellulase at 45?°C temperature, carboxyl methyl cellulose (CMC) as carbon source and trypton as a nitrogen source. The bacterial crude enzyme was purified by ammonium sulfate precipitation followed by overnight dialysis. SDS-PAGE analysis of the partially purified cellulase enzyme exhibited band sizes of approximately 55 and 72?kDa. 相似文献
76.
Sangeeta Mehta Rakhee Chhetra Radhika Srinivasan Suresh C. Sharma Digambar Behera Sujata Ghosh 《Glycoconjugate journal》2010,27(5):491-500
In this study, we report the presence of significantly higher level of GM3 specific IgG antibodies (IgGTL) in the bronchoalveolar lavage fluid obtained from tumor bearing lung of non-small cell lung cancer (NSCLC) patients as compared
to other non-neoplastic controls. The antibodies were isolated using DEAE-cellulose anion exchange chromatography and molecular
weight of the subunits of IgGTL was confirmed in SDS-PAGE. IgGTL revealed high specificity to GM3 and the IgG distribution was confined to IgG1. Furthermore, IgGTL showed strong reactivity with NSCLC cell lines as well as the tissue biopsies and cells obtained from fine needle aspirations
of NSCLC patients. A 66 kDa membrane glycoprotein of NSCLC cell lines was found to interact specifically with IgGTL, the intensity of which was drastically reduced in presence of GM3. Further, binding of Maackia amurensis agglutinin [specific for NeuAcα(2→3)Gal unit , the same disaccharide unit also known to be present in GM3] to the 66 kDa
band confirmed it to be a sialoglycoprotein in nature. IgGTL could not show any reactivity to alkaline borohydrate treated or periodate oxidised membrane fractions, suggesting the probable
involvement of the carbohydrate moiety of the 66 kDa glycoprotein in the interaction with IgGTL. Thus, the 66 kDa sialoglycoprotein seems to be the NSCLC specific sialoglycoconjugate. Taken together, IgGTL antibodies may have the potential to serve as a unique probe for detail investigation of NSCLC specific cell surface sialoglycoconjugate.
Further, due to high specificity of IgGTL to GM3, it may be possible to develop a simple alternative diagnostic approach (GM3-ELISA) for NSCLC. 相似文献
77.
Nilesh Kumar Sharma Shuvashish Behera Richa Arora Sachin Kumar 《Bioprocess and biosystems engineering》2016,39(5):835-843
The evolutionary adaptation was carried out on the thermotolerant yeast Kluyveromyces marxianus NIRE-K1 at 45 °C up to 60 batches to enhance its xylose utilization capability. The adapted strain showed higher specific growth rate and 3-fold xylose uptake rate and short lag phase as compared to the native strain. During aerobic growth adapted yeast showed 2.81-fold higher xylose utilization than that of native. In anaerobic batch fermentation, adapted yeast utilized about 91 % of xylose in 72 h and produced 2.88 and 18.75 g l?1 of ethanol and xylitol, respectively, which were 5.11 and 5.71-fold higher than that of native. Ethanol yield, xylitol yield and specific sugar consumption rate obtained by the adapted cells were found to be 1.57, 1.65 and 4.84-fold higher than that of native yeast, respectively. Aforesaid results suggested that the evolutionary adaptation will be a very effective strategy in the near future for economic lignocellulosic ethanol production. 相似文献
78.
79.
The estimation of underground standing crop of individual plant species in a natural grassland ecosystem without direct measurement of screened plant material is described. A mathematical formulation techinque has been designed by correlating the variables fresh weight, dry weight, ash weight and also nitrogen, phosphorus, potassium, sodium, calcium, sulphur and magnesium content of the plant species. 相似文献
80.
Mandal EK Maity K Maity S Gantait SK Behera B Maiti TK Sikdar SR Islam SS 《Carbohydrate research》2012,347(1):172-177
An immunostimulating water-soluble glucan was isolated from hot aqueous extract of fruit bodies of an edible mushroom Calocybe indica. Structural investigation of the glucan was carried out using acid hydrolysis, methylation analysis, and NMR studies ((1)H, (13)C, DEPT-135, TOCSY, DQF-COSY, NOESY, ROESY, HMQC, and HMBC). On the basis of above-mentioned experiments, the structure of the repeating unit of the polysaccharide was established as [see figure in text]. This glucan stimulated the splenocytes and thymocytes. 相似文献