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31.
Biodiesel fuel is found to be a promising alter- native for the petroleum diesel based on the results published by the researchers for a decade. Biodiesel fuel is renewable and non degradable fuel. Many countries use biodiesel fuel for automotives to meet the crisis due to the depletion of the petroleum fuel and to meet the stringent emission norms. Various researches have been carried out with different bio- diesel fuels with vegetable oil as the source and appreciable results were reported. Few biodiesel fuels which have been already tested are Jatropha, Pongamia, Mahua, neem, cotton seed, etc. In this experimental work, Adelfa biodiesel blend is used as the test fuel. The emission and performance charac- teristics were compared with three other different biodiesel fuel blends. Appreciable results imply that Adelfa biodiesel (Nerium oil methyl ester) can be a futuristic biodiesel fuel, which has a good compatibility with the direct injection (DI) diesel engine without any major modification. Moreover, Adelfa can be cultivated in a non agricultural land with fewer sources of water. It is widely spread over all major countries of Asia. Experimental investigations have been carried out on a single cylinder DI diesel engine with standard engine speci- fications. In this experimental work, various Adelfa biodiesel blends is compared with reference fuel (diesel) to choose the best blend which gives a closer performance to diesel. The comparative analysis with other biodiesel fuels has also been done and results have been discussed.  相似文献   
32.
The complete genome of an individual by massively parallel DNA sequencing   总被引:3,自引:0,他引:3  
The association of genetic variation with disease and drug response, and improvements in nucleic acid technologies, have given great optimism for the impact of 'genomic medicine'. However, the formidable size of the diploid human genome, approximately 6 gigabases, has prevented the routine application of sequencing methods to deciphering complete individual human genomes. To realize the full potential of genomics for human health, this limitation must be overcome. Here we report the DNA sequence of a diploid genome of a single individual, James D. Watson, sequenced to 7.4-fold redundancy in two months using massively parallel sequencing in picolitre-size reaction vessels. This sequence was completed in two months at approximately one-hundredth of the cost of traditional capillary electrophoresis methods. Comparison of the sequence to the reference genome led to the identification of 3.3 million single nucleotide polymorphisms, of which 10,654 cause amino-acid substitution within the coding sequence. In addition, we accurately identified small-scale (2-40,000 base pair (bp)) insertion and deletion polymorphism as well as copy number variation resulting in the large-scale gain and loss of chromosomal segments ranging from 26,000 to 1.5 million base pairs. Overall, these results agree well with recent results of sequencing of a single individual by traditional methods. However, in addition to being faster and significantly less expensive, this sequencing technology avoids the arbitrary loss of genomic sequences inherent in random shotgun sequencing by bacterial cloning because it amplifies DNA in a cell-free system. As a result, we further demonstrate the acquisition of novel human sequence, including novel genes not previously identified by traditional genomic sequencing. This is the first genome sequenced by next-generation technologies. Therefore it is a pilot for the future challenges of 'personalized genome sequencing'.  相似文献   
33.
MD2, a 160-residue accessory glycoprotein, is responsible for the recognition and binding of Gram-negative bacterial membrane component, lipopolysaccharide (LPS). Internalization of pathogen inside the mononuclear phagocytes has also been attributed to MD2 which leads to the clearance of pathogens from the host. However, not much is known about the segments in MD2 that are responsible for LPS interaction or internalization of pathogen inside the defense cells. A 16-residue stretch (MD54) from MD2 protein has been identified that possesses a short heptad repeat sequence and four cationic residues enabling it to participate in both hydrophobic and electrostatic interactions with LPS. An MD54 analog of the same size was also designed in which a leucine residue at a heptadic position was replaced with an alanine residue. MD54 but not its analog, MMD54 induced aggregation of LPS and aided in its internalization within THP-1 monocytes. Furthermore, MD54 inhibited LPS-induced nuclear translocation of NF-κB in PMA-treated THP-1 and TLR4/MD2/CD14-transfected HEK-293T cells and the production of pro-inflammatory cytokines. In addition, in in vivo experiments, MD54 showed marked protection and survival of mice against LPS-induced inflammation and death. Overall, we have identified a short peptide with heptad repeat sequence from MD2 that can cause aggregation of LPS and abet in its internalization within THP-1 cells, resulting in attenuation of LPS-induced pro-inflammatory responses in vitro and in vivo.  相似文献   
34.
Summary Triweekly i.m. injections of clomiphene citrate (group 1, 25 g/0.5 ml and group II, 50 g/1.0 ml) were administered for a period of 3 months during the preparatory period to female fresh water teleosts exhibiting ovarian recrudescence, while a control group received 0.5 ml of physiological saline throughout the period of experimentation i.e., from February through April. 50 g clomiphene citrate treatment brought about a steady increase in ovarian size, and oocytes began to enlarge and mature and finally ovulation took place in April. This is 4 months ahead of their normal occurrence.The authors wish to express their gratitude to Richardson Merrel Co. for supplying the sample of clomiphene citrate, and Dr K.N. Udupa, Institute of Medical Sciences, Banaras Hindu University, Varanasi for facilities.  相似文献   
35.
Summary Synthetic analogue of ecdysone, 3, 14-dihydroxy-5-cholest-7-en-6-one did not bring the scorpionPalamnaeus bengalensis to moult. It also failed completely in stimulating the scorption to produce any change related to moulting.Acknowledgment. Author is grateful to Dr Suresh C. Shrivastava for providing research facilities, Dr S.P. Tewarson for encouragement and S.C.S.T. (U.P.) for funds. Present address: Department of Zoology, Lucknow Christian College, Lucknow-226001.  相似文献   
36.
T C Kumar  F Knowles 《Nature》1967,215(5096):54-55
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37.
Bi_(2/3)Cu_3Ti_4O_(12)(BCTO) ceramic was synthesized by the semi-wet route using metal nitrate solutions and solid TiO_2 powder in a stoichiometric ratio. Fourier transform infrared(FTIR) study of BCTO precursor powder and calcined ceramic showed the presence of alcoholic functional groups and the stretching band of Ti-O and Cu-O respectively. X-ray diffraction(XRD), scanning electron microscope(SEM) and energy dispersive x-ray spectroscopy(EDX) were employed to characterize the structure, surface morphology and purity of the sintered BCTO ceramic respectively. X-ray diffraction study confirmed the single phase formation of BCTO ceramic at1073 K. The average dimension of grains calculated by SEM and AFM was found to be in the range of 0.73 ±0.2 μm with clear grain boundaries. Magnetic property was investigated over a wide temperature range 2–300 K at a magnetic field of 7 tesla. The Curie temperature was calculated by zero field cooled(M~(ZFC)) and field cooled(M~(FC)) magnetization at 100 Oe applied field which was found to be 125 K. The sintered BCTO ceramic shows high dielectric constant(ε'=2.9×10~4) at 323 K and 100 Hz.  相似文献   
38.
Amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD) are fatal neurodegenerative disorders that have common molecular and pathogenic characteristics, such as aberrant accumulation and ubiquitylation of TDP-43; however, the mechanisms that drive this process remain poorly understood. We have recently identified CCNF mutations in familial and sporadic ALS and FTD patients. CCNF encodes cyclin F, a component of an E3 ubiquitin–protein ligase (SCFcyclin F) complex that is responsible for ubiquitylating proteins for degradation by the ubiquitin–proteasome system. In this study, we examined the ALS/FTD-causing p.Ser621Gly (p.S621G) mutation in cyclin F and its effect upon downstream Lys48-specific ubiquitylation in transfected Neuro-2A and SH-SY5Y cells. Expression of mutant cyclin FS621G caused increased Lys48-specific ubiquitylation of proteins in neuronal cells compared to cyclin FWT. Proteomic analysis of immunoprecipitated Lys48-ubiquitylated proteins from mutant cyclin FS621G-expressing cells identified proteins that clustered within the autophagy pathway, including sequestosome-1 (p62/SQSTM1), heat shock proteins, and chaperonin complex components. Examination of autophagy markers p62, LC3, and lysosome-associated membrane protein 2 (Lamp2) in cells expressing mutant cyclin FS621G revealed defects in the autophagy pathway specifically resulting in impairment in autophagosomal–lysosome fusion. This finding highlights a potential mechanism by which cyclin F interacts with p62, the receptor responsible for transporting ubiquitylated substrates for autophagic degradation. These findings demonstrate that ALS/FTD-causing mutant cyclin FS621G disrupts Lys48-specific ubiquitylation, leading to accumulation of substrates and defects in the autophagic machinery. This study also demonstrates that a single missense mutation in cyclin F causes hyper-ubiquitylation of proteins that can indirectly impair the autophagy degradation pathway, which is implicated in ALS pathogenesis.  相似文献   
39.
40.
Objective: A natural cyclic peptide previously isolated from Citrus medica was synthesized by coupling of tetrapeptide units Boc-Leu-Pro-Trp-Leu-OMe and Boc-Ile-Ala-Ala-Gly-OMe after proper deprotection at carboxyl and amino terminals followed by cyclization of linear octapeptide segment. Methods: Solution phase technique was adopted for the synthesis of cyclooctapeptide-sarcodactylamide. Required tetrapeptide units were prepared by coupling of Boc-protected dipeptides viz. Boc-Leu-Pro-OH and Boc-Ile-Ala-OH with respective dipeptide methyl esters Trp-Leu-OMe and Ala-Gly-OMe. Cyclization of linear octapeptide unit was done by p-nitrophenyl ester method. The structure of synthesized cyclopolypeptide was elucidated by FTIR, ^1H NMR, ^13C NMR, FABMS spectral data and elemental analysis. The newly synthesized peptide was evaluated for dif- ferent pharmacological activities including antimicrobial, anthelmintic and cytotoxic activities. Results: Synthesis of sarcodactylamide was accomplished with 〉78% yield utilizing dicyclohexylcarbodiimide (DCC) as coupling agent. Newly synthesized peptide possessed potent cytotoxic activity against Dalton's lymphoma ascites (DLA) and Ehrlich's ascites carcinoma (EAC) cell lines, in addition to moderate anthelmintic activity against earthworms Megascoplex konkanensis, Pontoscotex corethruses and Eudrilus sp. Moreover, cyclopolypeptide displayed good antimicrobial activity against pathogenic fungi Candida albicans and Gram-negative bacteria Pseudomonas aeruginosa, in comparison to standard drugs griseofulvin and ciprofloxacin. Conclusion: Solution phase technique employing DCC and triethylamine (TEA) as base proved to be effective for the synthesis of natural cyclooctapeptide. N-methyl morpholine (NMM) was found to be a better base for the cyclization of linear octapeptide unit in comparison to TEA and pyridine.  相似文献   
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