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721.
Garhwal Himalaya represents one of the richest zones of vegetational wealth in India. Pteridophytic flora is also interesting in its diversity and distribution, however, little is worked out on the economic aspects of these plants. Therefore, present communication pertains to the folk utilization of ferns and fern-allies by the inhabitants of Deoprayag Tehsil in Garhwal Himalaya. The studies are based on frequent field trips to various remote localities and collecting the information from the local inhabitants. The perusal of literature indicated several little known plants of folk utilization, and a large number of these could prove an important source of wider economic utility after phytochemical analysis. 相似文献
722.
Cross-linking of B-cell membrane immunoglobulin (Ig) receptors induces growth arrest at G1-S, leading to apoptosis and cell death in the immature lymphomas WEHI-231 and CH31, but not in the CH12 B-cell line. In this system, which has been used as a model for B-cell tolerance, we have established that these lymphomas produce active transforming growth factor beta (TGF-beta) when treated with anti-Ig and that their hierarchy of sensitivity to TGF-beta generally correlates with their growth inhibition by anti-Ig. TGF-beta, in turn, has been shown to interfere with the phosphorylation of the retinoblastoma gene product, pRB. Herein, we also demonstrate that in WEHI-231 B-lymphoma cells treated with anti-Ig for 24 h, the pRB protein is found to be predominantly in the underphosphorylated form, as previously reported for cells arrested by the exogenous addition of TGF-beta. However, neutralizing antibodies to TGF-beta failed to prevent growth inhibition by anti-Ig in WEHI-231 and CH31. When WEHI-231 lymphoma cells were selected for growth in TGF-beta, the majority of the TGF-beta-resistant clones remained sensitive to anti-Ig-mediated growth inhibition. In these clones, the retinoblastoma gene product was found to be in the underphosphorylated form after 24-h treatment with anti-Ig, but not with TGF-beta. These data show that anti-Ig treatment of murine B-cell lymphomas stimulates the production of active TGF-beta but that a TGF-beta-independent pathway may be responsible for the pRB underphosphorylation and cell cycle blockade. 相似文献
723.
Eleven single spore isolates of Fusarium udum, isolated from different pigeonpea growing regions in India, differed in their cultural and morphological characters with marked diversity in virulence towards susceptible variety T-21. 相似文献
724.
Different types of nursery inocula formulations, namely mixed indigenous cultures and Glomus intraradices Schenck and Smith, were compared with commercially available inoculants of AM fungi in a pot experiment using two horticultural
crops, Capsicum and Polianthes. Soil-based inocula and soil beads produced the highest response in both crops. Glomus intraradices resulted in the highest yield in both Polianthes (45% increase in spike length) and Capsicum (112% increase in fruit yield). Among the commercial inocula tested, only Mycorise enhanced spike length (33%) and fruit
yield (11%) in the two hosts. Overall AM colonization was higher in Polianthes than in Capsicum. Sheared root inocula of G. intraradices resulted in high colonization (upto 68%) but the yield enhancement was lower than with soil-based formulations. The mixed
indigenous culture produced the highest number of spores and propagules and commercial inocula the lowest.
Accepted: 2 February 1998 相似文献
725.
H. J. Hoben P. Somasegaran N. Boonkerd Y. D. Gaur 《World journal of microbiology & biotechnology》1994,10(5):538-542
Somatic antigens of Bradyrhizobium japonicum, Rhizobium sp. (Cicer arietinum) and Rhizobium sp. (Leucaena leucocephala) were prepared as standard, single-species type from cultured cells. Equal numbers of the cells of these rhizobia were then combined to obtain a mixed-rhizobial-species antigen preparation. Rabbits were immunized either with the standard, single-species type or with the mixed-rhizobial-species antigen preparations. The antisera developed from the mixed antigen immunization contained antibodies for all three rhizobial species, detectable at agglutination titres of over 800. The mixed-rhizobial-species antisera were made species specific by cross-absorption. The cross-absorbed and the mixed-rhizobial-species antisera were generally similar in quality for strain identification by agglutination, fluorescent antibodies, immunoblot and ELISA. A 66% reduction in cost was estimated for the production of antisera by immunization with mixed-rhizobial-species antigen.H.J. Hoben and P. Somasegaran are with the NifTAL Center and MIRCEN, University of Hawaii, 1000 Holomua Road, Paia, Maui, HI 96779-9744, USA: N. Boonkerd is with the School of Agricultural Technology, Suranaree University of Technology, University Avenue, Nakorn Racharsima, Thailand. Y.D. Gaur is with the Division of Microbiology, Indian Agricultural Research Institute, New Delhi-110012, India. 相似文献
726.
Amit Luthra Amit Gaur Ravishankar Ramachandran 《Biochimica et Biophysica Acta - Proteins and Proteomics》2013,1834(6):1181-1186
Rv3868 (EccA1) is an essential CbxX/CfqX-family ATPase of the Mycobacterium tuberculosis ESX-1 secretion system. Previously, we demonstrated that Rv3868 is composed of two domains; a regulatory N-terminal domain (NT-Rv3868) and an ATP binding C-terminal domain (CT-Rv3868). In the present report, chemical denaturation studies show that electrostatic interactions stabilize the Rv3868. Interestingly, Rv3868 has notable heat stability and retains about 50% of ATPase activity even at 60 °C. The C-terminal domain was found to be important for the heat stability as demonstrated by both enzymatic activity assays and thermal denaturation experiments. Furthermore a structure-sequence analysis based on the content of charged and aliphatic amino acids rationalizes the higher propensity of Rv3868 for thermophilic characteristics. 相似文献
727.
Morris PD Byrd AK Tackett AJ Cameron CE Tanega P Ott R Fanning E Raney KD 《Biochemistry》2002,41(7):2372-2378
Helicases are enzymes that use energy from nucleoside triphosphate hydrolysis to unwind double-stranded (ds) DNA, a process vital to virtually every phase of DNA metabolism. Helicases have been classified as either 5'-to-3' or 3'-to-5' on the basis of their ability to unwind duplex DNA adjacent to either a 5' or 3' single-stranded (ss) DNA overhang. However, there has been debate as to whether this substrate preference is indicative of unidirectional translocation on ssDNA. We developed an assay that monitors the ability of a helicase to displace streptavidin from biotinylated oligonucleotides [Morris, P. D., and Raney, K. D. (1999) Biochemistry 38, 5164-5171]. Two helicases identified as having 5'-to-3' polarity displaced streptavidin from the 3'-end of biotinylated oligonucleotides but not from the 5'-end. We performed similar experiments using the 3'-to-5' helicases from the hepatitis C virus (NS3) and SV40 virus (SV40 T antigen). NS3 and SV40 T antigen were able to displace streptavidin from a 5'-biotinylated oligonucleotide but not from a 3'-biotinylated oligonucleotide. NS3 and SV40 T antigen enhanced the spontaneous rate of dissociation of streptavidin from biotin 340-fold and 1700-fold, respectively. The ssDNA binding protein, gp32, did not enhance dissociation of streptavidin from either end of an oligonucleotide. For NS3, the rate of displacement was faster from a 5'-biotinylated 60mer than from a 5'-biotinylated 30mer. The strong directional bias in streptavidin displacement activity exhibited by each helicase is consistent with a directional bias in translocation on ssDNA. The dependence of the reaction with NS3 on the oligonucleotide length suggests that multiple NS3 monomers are necessary for optimal activity. 相似文献
728.
Debabrata Sarkar Sushruti Sharma Poonam Chandel Suman Kumar Pandey 《Plant Growth Regulation》2010,61(1):109-117
Gametoclonal variation that occurs in gametic cells in culture and is recovered in their regenerated derivatives has not been reported in potato (Solanum tuberosum L.). Based on a set of 24 differentiating phenotypic traits, canonical variates analysis genetically distinguished the androgenic (di)haploid (2n = 2x = 24) D4 from its tetraploid (2n = 4x = 48) anther-derived sibs and anther donor JTH/C-107. Nuclear microsatellite analysis over six polymorphic loci indicated that meiotic rearrangements and mutant alleles were primarily associated with the release of gametoclonal variation. The incidence of null alleles in D4 at the loci STACCAS3 and STM0031 was also indicative of mutations occurring within the priming sequence. Microsatellite results were supported by random amplified polymorphic DNA (RAPD) assays that characterized a total of 567 loci (bins) representing 4,258 amplified fragments. Sixty-five new RAPDs that were absent in the anther donor and in either of its parents, viz., S. phureja Juz. & Buk. IVP-35 and S. tuberosum cv. Kufri Jyoti were present in D4, indicating the occurrence of extensive recombinational events. The results have been discussed in the context of microsatellite null alleles providing the most conclusive evidence for gametoclonal variation. 相似文献
729.
Rashmi Singh Gaur Ling Cai Olli H. Tuovinen Karen M. Mancl 《Bioresource technology》2010,101(3):1106-1110
Fat, oil and grease in wastewater can be difficult to treat because of their slow decomposition. Traditional pretreatment facilities to remove fat, oil and grease from wastewater are increasingly costly. The hypothesis in this study was that pretreatment of animal fat-containing wastewater in sand and sand/gravel filters facilitates the conversion of slowly degradable organic matter measured as the difference between chemical oxygen demand (COD) and 5-day biochemical oxygen demand (BOD5) for subsequent biological treatment. The pretreatment was evaluated using simulated turkey-processing wastewater and coarse sand and sand/gravel filters at a constant hydraulic loading rate of 132 L/m2/day. Two types of fixed media reactors were employed: (i) one set with a varying depth of coarse sand, and (ii) the second was similar but with an additional pea gravel cap. The results indicated that the relative removal of COD was slightly improved in the sand bioreactors with a pea gravel cap irrespective of the depth of coarse sand, but partial conversion to BOD5 was not consistently demonstrated. Pea gravel may act as a sieve to entrap organic matter including fat globules from the wastewater. Multiple dosing at the same daily loading rate slightly improved the treatment efficiency of the sand bioreactors. The ratios of influent-COD/effluent-COD were always greater than 1.0 following a change in the dosing frequency after a rest period, suggesting that organic matter, specifically fat globules in this case, was retained by the column matrix. 相似文献
730.
Aspergillus fumigatus, the main etiological agent for various forms of human aspergillosis, gets access to the respiratory system of human host by inhalation of airborne conidia. These conidia possibly adhere to extracellular matrix (ECM) proteins. Among the ECM proteins involved in adherence, fibrinogen is thought to be crucial. Here, we studied whether A. fumigatus three-week culture filtrate (3wcf) proteins promote binding of A. fumigatus to ECM proteins and promote fungal growth. We observed that incubation of ECM with 3wcf proteins led to dose- and time-dependent increase in adherence of conidia to the ECM. In order to identify the catalogue of fibrinogen-binding A. fumigatus proteins, we carried out fibrinogen affinity blotting using two-dimensional gel electrophoresed 3wcf proteins. A total of 15 fibrinogen-binding protein spots corresponding to 7 unique proteins were identified in 3wcf using matrix-assisted laser desorption/ionization-time of flight (MALDI-TOF-TOF). Among these, 4 proteins, namely, beta-glucosidase, alpha-mannosidase, pectate lyase A and oryzin precursor were predicted to have cell wall or extracellular localization, whereas amidase family protein and two hypothetical proteins did not display the signal sequence. This study reports seven novel fibrinogen-binding proteins of A. fumigatus, some of which could be further explored for targeting the adhesion phenomenon as antifungal strategy. 相似文献