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101.
102.
Melody Cabrera Ospino Hisaya Kojima Tomohiro Watanabe Tomoya Iwata Manabu Fukui 《Limnology》2018,19(2):177-183
Anaerobic arsenite oxidation is potentially important but the least understood process in the arsenic cycle. The catalytic subunit of the key enzyme for anaerobic arsenite oxidation is encoded by the arxA gene. In this study, a novel primer pair for the arxA gene was designed to detect diverse sequences of this notable gene. Further modification of the designed primer was made by adding extra bases to its 5′- end. This modification made it possible to analyze the PCR products with TA cloning, which provides higher throughput of investigations. With the combination of modified primer pair and TA cloning, diverse arxA gene sequences were effectively obtained from samples of lake water, spring water, and hot spring microbial mat. The sequences detected in the samples characterized by low salinity and nearly neutral pH were phylogenetically distinct from the majority of previously known arxA genes, found in the genome of alkaliphiles and halophiles. 相似文献
103.
104.
Masahiko Yamamoto Takeshi Yasuda Kiyoshi Hayasaka A. Ohnishi Hiroo Yoshikawa Takehiko Yanagihara Tohru Ikegami Tatsunori Yamamoto Hirofumi Ohashi Tomoya Nishimura Terunori Mitsuma Hidenori Kiyosawa Phillip F. Chance G. Sobue 《Human genetics》1997,100(2):151-154
We have used human β2 and β4 cDNA probes to map the genes encoding two isoforms of the regulatory β subunit of voltage-activated
Ca2+ channels, viz. CACNB2 (β2) and CACNB4 (β4), to human chromosomes 10p12 and 2q22-q23, respectively, by fluorescence in situ
hybridization. The gene encoding the β2 protein, first described as a Lambert-Eaton myasthenic syndrome (LEMS) antigen in
humans, is found close to a region that undergoes chromosome rearrangements in small cell lung cancer, which occurs in association
with LEMS. CACNB2 (β2) and CACNB4 (β4) genes are members of the ion-channel gene superfamily and it should now be possible
to examine their loci by linkage analysis of ion-channel-related disorders. To date, no such disease-related gene has been
assigned to 10p12 and 2q22-q23.
Received: 5 February 1997 / Accepted: 4 April 1997 相似文献
105.
106.
Essential roles of high-mobility group box 1 in the development of murine colitis and colitis-associated cancer 总被引:3,自引:0,他引:3
Maeda S Hikiba Y Shibata W Ohmae T Yanai A Ogura K Yamada S Omata M 《Biochemical and biophysical research communications》2007,360(2):394-400
High-mobility group box 1 (HMGB1) is a nuclear factor released extracellularly as a proinflammatory cytokine. We measured the HMGB1 concentration in the sera of mice with chemically induced colitis (DSS; dextran sulfate sodium salt) and found a marked increase. Inhibition of HMGB1 by neutralizing anti-HMGB1 antibody resulted in reduced inflammation in DSS-treated colons. In macrophages, HMGB1 induces several proinflammatory cytokines, such as IL-6, which are regulated by NF-kappaB activation. Two putative sources of HMGB1 were explored: in one, bacterial factors induce HMGB1 secretion from macrophages and in the other, necrotic epithelial cells directly release HMGB1. LPS induced a small amount of HMGB1 in macrophages, but macrophages incubated with supernatant prepared from necrotic cells and containing large amounts of HMGB1 activated NF-kappaB and induced IL-6. Using the colitis-associated cancer model, we demonstrated that neutralizing anti-HMGB1 antibody decreases tumor incidence and size. These observations suggest that HMGB1 is a potentially useful target for IBD treatment and the prevention of colitis-associated cancer. 相似文献
107.
108.
Rafael E. Ummus Janice Onuki Dieter Drnemann Marisa H. G. Medeiros Paolo Di Mascio 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》1999,729(1-2)
In this work we describe a sensitive method for the detection of 4,5-dioxovaleric acid (DOVA). 4,5-Dioxovaleric acid is derivatized with 2,3-diaminonaphthalene to form 3-(benzoquinoxalinyl-2)propionic acid (BZQ), a product with favorable UV absorbance and fluorescence properties. The high-performance liquid chromatographic method with UV absorbance and fluorescence detection is simple and its detection limit is approximately 100 fmol. This method was used to detect 4,5-dioxovaleric acid formation during metal-catalyzed 5-aminolevulinic acid (ALA) oxidation. Iron and ferritin were active in the formation of 4,5-dioxovaleric acid in the presence of 5-aminolevulinic acid. In addition, HPLC–MS–MS assay was used to characterize BZQ. The determination of 4,5-dioxovaleric acid is of great interest for the study of the mechanism of the metal-catalyzed damage of biomolecules by 5-aminolevulinic acid. This reaction may play a role in carcinogenesis after lead intoxication. The high frequency of liver cancer in acute intermittent porphyria patients may also be due to this reaction. 相似文献
109.
De Novo Synthesis of Sphingolipids Is Required for Cell Survival by Down-Regulating c-Jun N-Terminal Kinase in Drosophila Imaginal Discs
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110.
Crystalline features of cellulose microfibrils in the cell walls of Glaucocystis (Glaucophyta) were studied by combined spectroscopy and diffraction techniques, and the results were compared with those of Oocystis (Chlorophyta). Although these algae are grouped into two different classes, by the composition of their chloroplasts for instance, their cell walls are quite similar in size and morphology. The most striking features of their cellulose crystallites are that they have the highest cellulose Iα contents reported to date. In particular, the Iα fraction of cellulose from Glaucocystis was found to be as high as 90% from 13C NMR analysis. The mode of preferential orientation of cellulose crystallites in their cell walls is also interesting; equatorial 0.53-nm lattice planes were oriented parallel to the cell surface in the case of Glaucocystis, while the 0.62-nm planes were parallel to the Oocystis cell surface. Such a structural variation provides another link to the evolution of cellulose structure, biosynthesis, and its biocrystallization mechanism. 相似文献