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961.
Heat-treatment method for producing fatty acid-bound alpha-lactalbumin that induces tumor cell death
Kamijima T Ohmura A Sato T Akimoto K Itabashi M Mizuguchi M Kamiya M Kikukawa T Aizawa T Takahashi M Kawano K Demura M 《Biochemical and biophysical research communications》2008,376(1):211-214
HAMLET (Human Alpha-lactalbumin Made LEthal to Tumor cells), which was identified in human breast milk as an alpha-lactalbumin (LA)-oleic acid complex, kills tumor cells, selectively. Although it may have potential as a therapeutic agent against various tumor cells, only low-volume methods for its production exist. In this study, heat treatment was used to produce complexes from LAs and oleic acid using a simple method. In the case of human LA and oleic acid, heat-treated samples apparently showed much stronger activities than those treated at room temperature, with cytotoxicities equal to that of HAMLET. Furthermore, circular dichroism spectroscopy revealed that heat-treated samples lost their tertiary structure, suggesting a molten globule as oleic acid-bound LA. BLA samples also showed strong activities by heat treatment. Batch production with heat treatment can efficiently convert LAs into tumoricidal complexes. 相似文献
962.
Here we discuss the mechanisms for the degradation of excess peroxisomes in mammalian hepatocytes which include (a) autophagy,
(b) the action of peroxisomal Lon protease and (c) the membrane disrupting effect of 15-lipoxygenase. A recent study using
Atg7 conditional-knock-out mice revealed that 70–80% of excess peroxisomes are degraded by the autophagic process. The remaining
20–30% of excess peroxisomes is most probably degraded by the action of peroxisomal Lon protease. Finally, a selective disruption
of the peroxisomal membrane has been shown to be mediated by 15-lipoxygenase activity which is followed by diffusion of matrix
proteins into the cytoplasm and cytoplasmic proteolysis.
Presented at the 50th Anniversary Symposium of the Society for Histochemistry, Interlaken, Switzerland, October 1–4, 2008. 相似文献
963.
Makoto Shiozaki Hiroto Imai Katsuya Maeda Tomoya Miura Katsutaka Yasue Akira Suma Masahiro Yokota Yosuke Ogoshi Julia Haas Andrew M. Fryer Ellen R. Laird Nicole M. Littmann Steven W. Andrews John A. Josey Takayuki Mimura Yuichi Shinozaki Hiromi Yoshiuchi Takashi Inaba 《Bioorganic & medicinal chemistry letters》2009,19(21):6213-6217
A series of 1-sulfonylaminocyclopropanecarboxylates was synthesized as ADAMTS-5 (Aggrecanase-2) inhibitors. After an intensive investigation of the central cyclopropane core including its absolute stereochemistry and substituents, we found compound 22 with an Agg-2 IC50 = 7.4 nM, the most potent ADAMTS-5 inhibitor reported so far. 相似文献
964.
Fumio Matsuda Yoko Shinbo Akira Oikawa Masami Yokota Hirai Oliver Fiehn Shigehiko Kanaya Kazuki Saito 《PloS one》2009,4(10)
Background
In metabolomics researches using mass spectrometry (MS), systematic searching of high-resolution mass data against compound databases is often the first step of metabolite annotation to determine elemental compositions possessing similar theoretical mass numbers. However, incorrect hits derived from errors in mass analyses will be included in the results of elemental composition searches. To assess the quality of peak annotation information, a novel methodology for false discovery rates (FDR) evaluation is presented in this study. Based on the FDR analyses, several aspects of an elemental composition search, including setting a threshold, estimating FDR, and the types of elemental composition databases most reliable for searching are discussed.Methodology/Principal Findings
The FDR can be determined from one measured value (i.e., the hit rate for search queries) and four parameters determined by Monte Carlo simulation. The results indicate that relatively high FDR values (30–50%) were obtained when searching time-of-flight (TOF)/MS data using the KNApSAcK and KEGG databases. In addition, searches against large all-in-one databases (e.g., PubChem) always produced unacceptable results (FDR >70%). The estimated FDRs suggest that the quality of search results can be improved not only by performing more accurate mass analysis but also by modifying the properties of the compound database. A theoretical analysis indicates that FDR could be improved by using compound database with smaller but higher completeness entries.Conclusions/Significance
High accuracy mass analysis, such as Fourier transform (FT)-MS, is needed for reliable annotation (FDR <10%). In addition, a small, customized compound database is preferable for high-quality annotation of metabolome data. 相似文献965.
Md. Mahabubur Rahman Muhammad Nurul Amin Futoshi Ishiguri Shinso Yokota Rubaiyat Sharmin Sultana Yuya Takashima Kazuya Iizuka Nobuo Yoshizawa 《Plant biotechnology reports》2009,3(3):259-266
A plantlet regeneration protocol was developed on pot-grown mature plants of Elaeocarpus robustus Roxb. cv. Dwarf from nodal and leaf explants. The best yield of adventitious shoots was achieved from the leaf-derived calli
in a modified MS (MMS1, half strength of major salts, full strength of minor salts, and vitamins) medium containing 4.0 μM BA + 4.0 μM Kn + 0.5 μM
NAA + 15% coconut water (CW). The shoot multiplication rate was amplified about twofold per culture after the addition of
15% CW to the medium. The rate of shoot multiplication reached maximum at the 5th subculture, and it maintained this rate
throughout the 3 subsequent subcultures. The best rooting in vitro was investigated by subculturing the microcuttings in an
MMS2 (half strength of both major salts and minor salts and full strength of vitamins) medium containing 1.0 μM IBA in the dark
for one initial week at 30°C, followed by subculturing them in a plant-growth regulator (PGR)-free medium in the light. The
plantlets raised in vitro were successfully established under ex vitro conditions. 相似文献
966.
Theaflavins are reddish-colored polyphenols in black tea. To test the efficacy of theaflavin administration on body fat and muscle, we performed a randomized, double-blind, placebo-controlled study and investigated the effect of theaflavins administration on the body composition using of healthy subjects. In this study, 30 male and female Japanese were enrolled and participants were randomly allocated to receive placebo, theaflavin (50 or 100 mg/day), or catechin (400 mg/ml) for 10 weeks. The effects were evaluated using body weight, body fat percentage, subcutaneous fat percentage, and skeletal muscle percentage. Theaflavin administration significantly improved body fat percentage, subcutaneous fat percentage, and skeletal muscle percentage when compared to with the placebo. In contrast, there was no significant difference in all measured outcomes between the catechin and the placebo groups. The results indicate that oral administration of theaflavin had a beneficial effect on body fat and muscle in healthy individuals. 相似文献
967.
Takahiro Kihara Ayaka Hiroe Manami Ishii-Hyakutake Kouhei Mizuno 《Bioscience, biotechnology, and biochemistry》2017,81(8):1627-1635
Bacillus cereus and Bacillus megaterium both accumulate polyhydroxyalkanoate (PHA) but their PHA biosynthetic gene (pha) clusters that code for proteins involved in PHA biosynthesis are different. Namely, a gene encoding MaoC-like protein exists in the B. cereus-type pha cluster but not in the B. megaterium-type pha cluster. MaoC-like protein has an R-specific enoyl-CoA hydratase (R-hydratase) activity and is referred to as PhaJ when involved in PHA metabolism. In this study, the pha cluster of B. cereus YB-4 was characterized in terms of PhaJ’s function. In an in vitro assay, PhaJ from B. cereus YB-4 (PhaJYB4) exhibited hydration activity toward crotonyl-CoA. In an in vivo assay using Escherichia coli as a host for PHA accumulation, the recombinant strain expressing PhaJYB4 and PHA synthase led to increased PHA accumulation, suggesting that PhaJYB4 functioned as a monomer supplier. The monomer composition of the accumulated PHA reflected the substrate specificity of PhaJYB4, which appeared to prefer short chain-length substrates. The pha cluster from B. cereus YB-4 functioned to accumulate PHA in E. coli; however, it did not function when the phaJYB4 gene was deleted. The B. cereus-type pha cluster represents a new example of a pha cluster that contains the gene encoding PhaJ. 相似文献
968.
Since the early days of manned spaceflight, hazardous effects of the space environment on living organisms have been disputed. With the continuous manning of the International Space Station, the planned Chinese space station, and renewed interest in returning to the Moon and sending manned flights to Mars, identifying and addressing the potential outcomes of long-term space exposures is critically important. 相似文献
969.
Self-organized formation of polarized cortical tissues from ESCs and its active manipulation by extrinsic signals 总被引:1,自引:0,他引:1
Eiraku M Watanabe K Matsuo-Takasaki M Kawada M Yonemura S Matsumura M Wataya T Nishiyama A Muguruma K Sasai Y 《Cell Stem Cell》2008,3(5):519-532
Here, we demonstrate self-organized formation of apico-basally polarized cortical tissues from ESCs using an efficient three-dimensional aggregation culture (SFEBq culture). The generated cortical neurons are functional, transplantable, and capable of forming proper long-range connections in vivo and in vitro. The regional identity of the generated pallial tissues can be selectively controlled (into olfactory bulb, rostral and caudal cortices, hem, and choroid plexus) by secreted patterning factors such as Fgf, Wnt, and BMP. In addition, the in vivo-mimicking birth order of distinct cortical neurons permits the selective generation of particular layer-specific neurons by timed induction of cell-cycle exit. Importantly, cortical tissues generated from mouse and human ESCs form a self-organized structure that includes four distinct zones (ventricular, early and late cortical-plate, and Cajal-Retzius cell zones) along the apico-basal direction. Thus, spatial and temporal aspects of early corticogenesis are recapitulated and can be manipulated in this ESC culture. 相似文献