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91.
Yeon Ho Je Jin Hee Chang Mi Hyang Kim Jong Yul Roh Byung Rae Jin David R. O''''Reilly 《Biotechnology letters》2001,23(21):1809-1817
A system is described for the rapid generation of Bombyx mori nucleopolyhedrovirus (BmNPV)-based expression vectors. A series of novel BmNPV genomes, that include a mini-F replicon and therefore can be maintained in Escherichia coli, have been generated. These genomes lack a portion of the essential ORF1629 gene and cannot replicate independently in insect cells. However, they can be used as parental genomes for the generation of expression vectors by cotransfection with a transfer plasmid that includes an intact ORF1629. Only recombinant viruses that have acquired the ORF1629 gene from the transfer vector, and have therefore also acquired the foreign gene of interest, can replicate after cotransfection. Parental genomes with and without a polyhedrin gene are described, enabling the generation of occlusion-positive and occlusion-negative recombinant viruses. Occlusion-positive expression vectors enable the oral infection of B. mori larvae and can therefore be used for the mass production of a foreign protein in infected insects. 相似文献
92.
Haeshin Lee Ji Hoon Jeong Je Hoon Lee Tae Gwan Park 《Biotechnology and Bioprocess Engineering》2001,6(4):269-273
This study presents a new formulation method for improving DNA transfection efficiency using a fusogenic peptide and polyethylene
glycol grafted polyethylenimine. Succinimidyl succinate polyethylene glycol (PEG-SSA) was conjugated with polyethylenimine
(PEI). PEI is well known for a good endosomal escaping and DNA condensing agent. The positively charged synthetic fusogenic
peptide, KALA, was coated on the negatively charged PEG-g-PEI/DNA and PEI/DNA complexes. The KALA/PEI/DNA complexes exhibited
aggregation behavior at higher KALA coating amounts with an effective diameter of around 1,000 nm. However, the KALA/PEG-g-PEI/DNA
complexes were 100–300 nm in size with a surface zeta-potential (ζ) value of about +20 mV. The conjugated PEG molecules suppressed
any KALA-mediated inter-particle aggregation, and thereby improved the transfection efficiency. Consequently, the transfection
efficiency of the KALA/PEG-g-PEI/DNA complexes was obtained by utilizing both the fusogenic activity of KALA and the steric
repulsion effect of PEC. 相似文献
93.
A novel extraction method was developed aiming at increasing the stability of enzymes in organic solvent media. Horseradish peroxidase (HRP), inactivated in a tetrahydrofuran (THF)/water (1:1, v/v), regained and maintained its activity when HRP was extracted by adding a THF/benzene mixture to the original solution. However, the HRP activity was drastically lowered in the enzyme-free blank solution that had been formed by employing the same extraction procedure. As a result, the reactivation after the extraction is believed to depend on enzyme history, and might be arisen from an irreversible structural change of the enzyme. 相似文献
94.
95.
Choi Jae Hee; Chung Gap Chae; Suh Sang Ryong; Yu Jung Ah; Sung Je Hoon; Choi Kyung Ju 《Plant & cell physiology》1997,38(4):495-498
Restriction of tomato roots by growth in small containers stronglysuppressed transport of 45Ca2+ ions to new leaves and apices.Water transport, expressed on a leaf area basis, was marginallyreduced by root restriction, an indication that calcium transportwas more severely limited than water transport. (Received October 11, 1996; Accepted January 27, 1997) 相似文献
96.
97.
Je‐Nie Phue Santosh B. Noronha Ritabrata Bhattacharyya Alan J. Wolfe Joseph Shiloach 《Biotechnology and bioengineering》2005,91(5):649-649
The original article to which this Erratum refers was published in Biotechnol Bioeng 2005;90:805–820 相似文献
98.
The freshwater bryozoan Pectinatella magnifica (Leidy, 1851) is an invasive species in many countries all over the world. Although native to North America, it has been found in many countries of Europe and Asia. Pectinatella magnifica forms the largest colonial masses from all recently known bryozoan species. Culturing this organism in an aquarium has never been achieved for more than few days so far. Colonies from laboratory culture are important for various studies on its biology and life cycle of this species in experimental conditions. Young colonies successfully hatched from germinating statoblasts of P. magnifica in the laboratory and were maintained over eight weeks. Moreover, this was the first time when the compound colonies of this species were carried from its natural habitat to the laboratory, into a special aquarium system, and kept alive for more than three weeks. In both experiments the physicochemical parameters of the water (temperature, concentration of dissolved oxygen, electrolytic conductivity and pH) and changes in weight of compound colonies of P. magnifica in laboratory conditions were checked. The results found in this study are essential for understanding the invasiveness of this species and identifying methods for elimination of its ecological risks because these are closely resembling those of other invasive species. 相似文献
99.
100.
Young Chul Kwon Sinil Kim Yong Seok Lee Je Chul Lee Myung-Je Cho Woo-Kon Lee Hyung-Lyun Kang Jae-Young Song Seung Chul Baik Hyeon Su Ro 《Journal of microbiology (Seoul, Korea)》2016,54(5):387-395
HP0059, an uncharacterized gene of Helicobacter pylori, encodes a 284-aa-long protein containing a nuclear localization sequence (NLS) and multiple leucine-rich heptad repeats. Effects of HP0059 proteins in human stomach cells were assessed by incubation of recombinant HP0059 proteins with the AGS human gastric carcinoma cell line. Wild-type HP0059 proteins showed cytotoxicity in AGS cells in a concentration-dependent manner, whereas NLS mutant protein showed no effect, suggesting that the cytotoxicity is attributed to host nuclear localization. AGS cells transfected with pEGFP-HP0059 plasmid showed strong GFP signal merged to the chromosomal DNA region. The chromosome was fragmented into multiple distinct dots merged with the GFP signal after 12 h of incubation. The chromosome fragmentation was further explored by incubation of AGS chromosomal DNA with recombinant HP0059 proteins, which leaded to complete degradation of the chromosomal DNA. HP0059 protein also degraded circular plasmid DNA without consensus, being an indication of DNase I activity. The DNase was activated by MgCl2, but not by CaCl2. The activity was completely blocked by EDTA. The optimal pH and temperature for DNase activity were 7.0–8.0 and 55°C, respectively. These results indicate that HP0059 possesses a novel DNase I activity along with a role in the genomic instability of human gastric cells, which may result in the transformation of gastric cells. 相似文献