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951.
Tadayoshi Kanao Moe Onishi Yasuyuki Kajitani Yuki Hashimoto Tatsuya Toge Hiroshi Kikukawa 《Bioscience, biotechnology, and biochemistry》2018,82(1):152-160
Tetrathionate hydrolase (4THase), a key enzyme of the S4-intermediate (S4I) pathway, was partially purified from marine acidophilic bacterium, Acidithiobacillus thiooxidans strain SH, and the gene encoding this enzyme (SH-tth) was identified. SH-Tth is a homodimer with a molecular mass of 97 ± 3 kDa, and contains a subunit 52 kDa in size. Enzyme activity was stimulated in the presence of 1 M NaCl, and showed the maximum at pH 3.0. Although 4THases from A. thiooxidans and the closely related Acidithiobacillus caldus strain have been reported to be periplasmic enzymes, SH-Tth seems to be localized on the outer membrane of the cell, and acts as a peripheral protein. Furthermore, both 4THase activity and SH-Tth proteins were detected in sulfur-grown cells of strain SH. These results suggested that SH-Tth is involved in elemental sulfur-oxidation, which is distinct from sulfur-oxidation in other sulfur-oxidizing strains such as A. thiooxidans and A. caldus. 相似文献
952.
Yusuke Sasaki Toshiyuki Takagi Keisuke Motone Toshiyuki Shibata Kouichi Kuroda 《Bioscience, biotechnology, and biochemistry》2018,82(8):1459-1462
A co-culture platform for bioethanol production from brown macroalgae was developed, consisting of two types of engineered Saccharomyces cerevisiae strains; alginate- and mannitol-assimilating yeast (AM1), and cellulase-displaying yeast (CDY). When the 5% (w/v) brown macroalgae Ecklonia kurome was used as the sole carbon source for this system, 2.1 g/L of ethanol was produced, along with simultaneous consumption of alginate, mannitol, and glucans. 相似文献
953.
954.
Involvement of chalcone reductase in the soybean isoflavone metabolon: identification of GmCHR5, which interacts with 2‐hydroxyisoflavanone synthase
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Ryo Mameda Toshiyuki Waki Yosuke Kawai Seiji Takahashi Toru Nakayama 《The Plant journal : for cell and molecular biology》2018,96(1):56-74
Soybean (Glycine max) 5‐deoxyisoflavonoids (daidzein and its conjugates) are precursors of glyceollin phytoalexins. They are also converted to equol by microbes in the human intestine, resulting in health benefits. 5‐Deoxyisoflavonoids accumulate in the roots (93% mol/mol of the total root isoflavonoids) and seeds of unstressed soybean plants. Chalcone reductase (CHR) is a key enzyme mediating 5‐deoxyisoflavonoid biosynthesis because it catalyzes the production of 6′‐deoxychalcone through its effects on the chalcone synthase (CHS)‐catalyzed reaction. The soybean genome encodes at least 11 CHR‐related homologs, but it is unclear which ones are functionally important for daidzein accumulation in unstressed plants. Among the CHR homologs, the temporal and spatial expression patterns of GmCHR5 were the most correlated with the distribution patterns of 5‐deoxyisoflavonoids. The CHR activity of GmCHR5 was confirmed in vitro and in planta. In the in vitro assays, the ratio of CHR products (6′‐deoxychalcone) to total CHS products (R value) was dependent on GmCHR5 and CHS concentrations, with higher concentrations resulting in higher R values (i.e. approaching 90%). Subcellular localization analyses revealed that GmCHR5 was present in the cytoplasm and nucleus. Protein–protein interaction assays indicated that GmCHR5, but not GmCHR1 and GmCHR6, interacted with 2‐hydroxyisoflavanone synthase (IFS) isozymes. The CHS isozymes also interacted with IFS isozymes but not with GmCHR5. The proposed micro‐compartmentalization of isoflavone biosynthesis through the formation of an IFS‐mediated metabolon is probably involved in positioning GmCHR5 close to CHS, resulting in an R value that is high enough for the accumulation of abundant 5‐deoxyisoflavonoids in soybean roots. 相似文献
955.
Takeshi Fukuda Takashi Ishiyama Takahiro Katagiri Kenjiro Ueda Sumie Muramatsu Masami Hashimoto Anri Aki Daichi Baba Kengo Watanabe Naoki Tanaka 《Bioorganic & medicinal chemistry letters》2018,28(20):3333-3337
Hepcidin has emerged as the central regulatory molecule in systemic iron homeostasis. The inhibition of hepcidin may be a favorable strategy for the treatment of anemia of chronic disease. Here, we have reported the design, synthesis, and structure–activity relationships (SAR) of a series of 4-aminopyrimidine compounds as inhibitors of hepcidin production. The optimization study of 1 led to the design of a potent and bioavailable inhibitor of hepcidin production, 34 (DS42450411), which showed serum hepcidin-lowering effects in a mouse model of interleukin-6-induced acute inflammation. 相似文献
956.
Miwa Fukuda Tomomi Sasaki Tomoko Hashimoto Hiroyuki Miyachi Minoru Waki Akira Asai Osamu Takikawa Osamu Ohno Kenji Matsuno 《Bioorganic & medicinal chemistry letters》2018,28(17):2846-2849
Kynurenine is biosynthesised from tryptophan catalysed by indoleamine 2,3-dioxygenase (IDO). The abrogation of kynurenine production is considered a promising therapeutic target for immunological cancer treatment. In the course of our IDO inhibitor programme, formal cyclisation of the isothiourea moiety of the IDO inhibitor 1 afforded the 5-Cl-benzimidazole derivative 2b-6, which inhibited both recombinant human IDO (rhIDO) activity and cellular kynurenine production. Further derivatisation of 2b-6 provided the potent inhibitor of cellular kynurenine production 2i (IC50?=?0.34?µM), which unexpectedly exerted little effect on the enzymatic activity of rhIDO. Elucidation of the mechanism of action revealed that compound 2i suppresses IDO expression at the protein level by inhibiting STAT1 expression in IFN-γ-treated A431 cells. The kynurenine-production inhibitor 2i is expected to be a promising starting point for a novel approach to immunological cancer treatment. 相似文献
957.
Yuta Murakami Koichi Takahashi Kyoka Hoshi Hiromi Ito Mayumi Kanno Kiyoshi Saito Kenneth Nollet Yoshiki Yamaguchi Masakazu Miyajima Hajime Arai Yasuhiro Hashimoto Tatsuo Mima 《Biochimica et Biophysica Acta (BBA)/General Subjects》2018,1862(8):1835-1842
Background
Spontaneous intracranial hypotension (SIH) is caused by cerebrospinal fluid (CSF) leakage. Definitive diagnosis can be difficult by clinical examinations and imaging studies.Methods
SIH was diagnosed with the following criteria: (i) evidence of CSF leakage by cranial magnetic resonance imaging (MRI) findings of intracranial hypotension and/or low CSF opening pressure; (ii) no recent history of dural puncture. We quantified CSF proteins by ELISA or Western blotting.Results
Comparing with non-SIH patients, SIH patients showed significant increase of brain-derived CSF glycoproteins such as lipocalin-type prostaglandin D synthase (L-PGDS), soluble protein fragments generated from amyloid precursor protein (sAPP) and “brain-type” transferrin (Tf). Serum-derived proteins such as albumin, immunoglobulin G, and serum Tf were also increased. A combination of L-PGDS and brain-type Tf differentiated SIH from non-SIH with sensitivity 94.7% and specificity 72.6%.Conclusion
L-PGDS and brain-type Tf can be biomarkers for diagnosing SIH.General significance
L-PGDS and brain-type Tf biosynthesized in the brain appears to be markers for abnormal metabolism of CSF. 相似文献958.
Uchiyama Hirofumi Iwai Atsushi Dohra Hideo Ohnishi Toshiyuki Kato Tatsuya Park Enoch Y. 《Applied microbiology and biotechnology》2018,102(10):4467-4475
Applied Microbiology and Biotechnology - Killer toxin resistant 6 (Kre6) and its paralog, suppressor of Kre null 1 (Skn1), are thought to be involved in the biosynthesis of cell wall... 相似文献
959.
Keisuke Motone Toshiyuki Takagi Shunsuke Aburaya Wataru Aoki Natsuko Miura Hiroyoshi Minakuchi Haruko Takeyama Yukio Nagasaki Chuya Shinzato Mitsuyoshi Ueda 《Marine biotechnology (New York, N.Y.)》2018,20(4):542-548
Coral reefs are one of the most biologically diverse and economically important ecosystems on earth. However, the destruction of coral reefs has been reported worldwide owing to rising seawater temperature associated with global warming. In this study, we investigated the potential of a redox nanoparticle (RNPO) to scavenge reactive oxygen species (ROS), which are overproduced under heat stress and play a crucial role in causing coral mortality. When reef-building coral (Acropora tenuis) larvae, without algal symbionts, were exposed to thermal stress at 33 °C, RNPO treatment significantly increased the survival rate. Proteome analysis of coral larvae was performed using nano-liquid chromatography-tandem mass spectrometry for the first time. The results revealed that several proteins related to ROS-induced oxidative stress were specifically identified in A. tenuis larvae without RNPO treatment, whereas these proteins were absent in RNPO-treated larvae, which suggested that RNPO effectively scavenged ROS from A. tenuis larvae. Results from this study indicate that RNPO treatment can reduce ROS in aposymbiotic coral larvae and would be a promising approach for protecting corals from thermal stress. 相似文献
960.
Cantharidin world in air: Spatiotemporal distributions of flying canthariphilous insects in the forest interior
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![点击此处可从《Entomological Science》网站下载免费的PDF全文](/ch/ext_images/free.gif)
The natural community in which the members interact using a toxic terpenoid cantharidin is named the “cantharidin world.” In previous studies, however, the members of this world have been surveyed only on the forest floor by setting pitfall traps with cantharidin as an attractant. In this study, we set cantharidin traps at various heights above the forest floor to investigate the structure and functional diversity of the canthariphilous flying insect community in the forest above‐ground space. A total of 3,168 arthropods were collected by the traps; among them, six species were more attracted to cantharidin than to control traps. Pseudopyrochroa brevitarsis and P. laticollis (Colecoptera: Pyrochroidae) both appeared for a short time during spring, but the latter species tended to use a lower layer of the forest. Clavicollis fugiens (Coleoptera: Anthicidae) also appeared in spring and flew near the ground. In these beetles, the attracted individuals were mostly males; they may use the obtained cantharidin for nuptial gifts to the female. Atrichopogon femoralis, A. insularis and Atrichopogon sp. (Diptera: Ceratopogonidae) were collected widely in the forest above‐ground space. These midges were almost females, probably because only females of these insects use chemical cues, including cantharidin, for searching for arthropods from which to suck hemolymph. 相似文献