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71.
Yusuke Shiromoto Satomi Kuramochi-Miyagawa Akito Daiba Shinichiro Chuma Ami Katanaya Akiko Katsumata Ken Nishimura Manami Ohtaka Mahito Nakanishi Toshinobu Nakamura Koichi Yoshinaga Noriko Asada Shota Nakamura Teruo Yasunaga Kanako Kojima-Kita Daisuke Itou Tohru Kimura Toru Nakano 《RNA (New York, N.Y.)》2013,19(6):803-810
piRNA (PIWI-interacting RNA) is a germ cell–specific small RNA in which biogenesis PIWI (P-element wimpy testis) family proteins play crucial roles. MILI (mouse Piwi-like), one of the three mouse PIWI family members, is indispensable for piRNA production, DNA methylation of retrotransposons presumably through the piRNA, and spermatogenesis. The biogenesis of piRNA has been divided into primary and secondary processing pathways; in both of these MILI is involved in mice. To analyze the molecular function of MILI in piRNA biogenesis, we utilized germline stem (GS) cells, which are derived from testicular stem cells and possess a spermatogonial phenotype. We established MILI-null GS cell lines and their revertant, MILI-rescued GS cells, by introducing the Mili gene with Sendai virus vector. Comparison of wild-type, MILI-null, and MILI-rescued GS cells revealed that GS cells were quite useful for analyzing the molecular mechanisms of piRNA production, especially the primary processing pathway. We found that glycerol-3-phosphate acyltransferase 2 (GPAT2), a mitochondrial outer membrane protein for lysophosphatidic acid, bound to MILI using the cells and that gene knockdown of GPAT2 brought about impaired piRNA production in GS cells. GPAT2 is not only one of the MILI bound proteins but also a protein essential for primary piRNA biogenesis. 相似文献
72.
Farsenyl pyrophosphate synthase is a potential molecular drug target of risedronate in Babesia bovis
Akio Ueno Mohamad Alaa Terkawi Miki Yokoyama Shinuo Cao Gabriel Aboge Mahmoud Aboulaila Yoshifumi Nishikawa Xuenan Xuan Naoaki Yokoyama Ikuo Igarashi 《Parasitology international》2013,62(2):189-192
A cDNA encoding farnesyl pyrophosphate synthase of Babesia bovis (BbFPPS) has been isolated, cloned and characterized as molecular drug target. Sequence analysis revealed that BbFPPS contains an open reading frame of 1011 bp with predicted 336 amino acids and molecular mass of 38 kDa. Antiserum raised in mice against recombinant BbFPPS expressed in Escherichia coli specifically reacted with native protein of B. bovis parasites by Western blot analysis and indirect immunofluorescent test. Enzymatic assay using recombinant BbFPPS revealed that the Km value of the enzyme for isopentenyl pyrophosphate and dimethylallyl pyrophosphate was 2.494 ± 1.536 μM. Risedronate inhibited the activity of BbFPPS yielding IC50 value of 8.4 ± 1.2 nM. Furthermore, the in vitro growth of B. bovis was significantly inhibited in the presence of a micromolar concentration of risedronate (IC50 = 4.02 ± 0.91 μM). No regrowth of B. bovis was observed at 10 μM of risedronate in the subsequent viability test. These results demonstrate that BbFPPS is the molecular target of risedronate, which could inhibit the in vitro growth of B. bovis. 相似文献
73.
Seiji Nishikawa 《Biotechnology & genetic engineering reviews》2013,29(1):149-170
Abstract Research involving differentiated embryonic stem (ES) cells may revolutionize the study of liver disease, improve the drug discovery process, and assist in the development of stem-cell-based clinical therapies. Generation of ES cell-derived hepatic tissue has benefited from an understanding of the cytokines, growth factors and biochemical compounds that are essential in liver development, and this knowledge has been used to mimic some aspects of embryonic development in vitro. Although great progress has been made in differentiating human ES cells into liver cells, current protocols have not yet produced cells with the phenotype of a mature hepatocyte. There is a of disease models have been examined concerning whether stem cells can correct liver disease. It is a bit premature to conclude that hepatocytes can be generated from non-hepatic cells in culture that will be clinically useful. Standard criteria will need to be developed to assess the extent to which human stem cell-derived hepatocytes have been produced. 相似文献
74.
Shuji Ohno Satomi Nakagawara Yoko Honda Shizuo Nakajin 《Molecular and cellular biochemistry》2013,381(1-2):145-156
11β-hydroxysteroid dehydrogenase (HSD11B) catalyzes the interconversion between active and inactive glucocorticoid, and is known to exist as two distinct isozymes: HSD11B1 and HSD11B2. A third HSD11B isozyme, HSD11B1L (SCDR10b), has recently been identified. Human HSD11B1L, which was characterized as a unidirectional NADP+-dependent cortisol dehydrogenase, appears to be specifically expressed in the brain. We previously reported that HSD11B1 and abundant HSD11B2 isozymes are expressed in neonatal pig testis and the Km for cortisol of NADP+-dependent dehydrogenase activity of testicular microsomes obviously differs from the same activity catalyzed by HSD11B1 from pig liver microsomes. Therefore, we hypothesized that the neonatal pig testis also expresses the third type of HSD11B isozyme, and we herein examined further evidence regarding the expression of HSD11B1L. (1) The inhibitory effects of gossypol and glycyrrhetinic acid on pig testicular microsomal NADP+-dependent cortisol dehydrogenase activity was clearly different from that of pig liver microsomes. (2) A highly conserved human HSD11B1L sequence was observed by RT-PCR in a pig testicular cDNA library. (3) mRNA, which contains the amplified sequence, was evaluated by real-time PCR and was most strongly expressed in pig brain, and at almost the same levels in the kidney as in the testis, but at lower levels in the liver. Based on these results, neonatal pig testis appears to express glycyrrhetinic acid-resistant HSD11B1L as a third HSD11B isozyme, and it may play a physiologically important role in cooperation with the abundantly expressed HSD11B2 isozyme in order to prevent Leydig cell apoptosis or GC-mediated suppression of testosterone production induced by high concentrations of activated GC in neonatal pig testis. 相似文献
75.
Patients with atopic dermatitis (AD) have superficial skin colonization with Staphylococcus aureus and an increased number of T helper (Th)2 cells in their peripheral blood. The purpose of this study was to clarify the involvement of interleukin (IL)‐10 secretion from Langerhans cells (LCs) in staphylococcal peptidoglycan (PEG)‐induced Th2 immune responses in mice. Mice were primed with LCs pulsed with PEG (or LPS) and ovalbumin (OVA) and then given a booster OVA injection 2 days later in the hind footpad. Five days after the OVA injection, cytokine responses in the draining popliteal lymph nodes were investigated by RT‐PCR and ELISA. Production of both IL‐10 and IL‐12 by cultured LCs was detected by ELISA. Administration of PEG‐ or LPS‐stimulated LCs into the hind footpads of the mice induced Th2‐prone and Th1‐prone immune responses, respectively, as represented by expression of IL‐4 and interferon ‐γ . In vitro experiments showed that PEG induced greater production of IL‐12 p40 from LCs than did LPS, whereas LPS induced greater production of IL‐12 p70 from LCs than did PEG. Furthermore, it was found that PEG‐stimulated LCs induced greater production of IL‐10 than did LPS‐stimulated LCs, and that neutralization of IL‐10 augmented IL‐12 p70 production and inhibited Th2 development by PEG‐stimulated LCs. These results suggest that PEG can induce Th2 development through down‐regulation of IL‐12 p70 production by LCs in an IL‐10 production‐dependent manner and would explain the role of S. aureus colonization in patients with AD. 相似文献
76.
Kanako Ishihara Kumiko Nakajima Satoko Kishimoto Fumiaki Atarashi Yasukazu Muramatsu Akitoyo Hotta Satomi Ishii Yasuyuki Takeda Masanori Kikuchi Yutaka Tamura 《Microbiology and immunology》2013,57(10):684-691
To determine and compare the extent of contamination caused by antimicrobial‐resistant lactic acid bacteria (LAB) in imported and domestic natural cheeses on the Japanese market, LAB were isolated using deMan, Rogosa and Sharpe (MRS) agar and MRS agar supplemented with six antimicrobials. From 38 imported and 24 Japanese cheeses, 409 LAB isolates were obtained and their antimicrobial resistance was tested. The percentage of LAB resistant to dihydrostreptomycin, erythromycin, and/or oxytetracycline isolated from imported cheeses (42.1%) was significantly higher than that of LAB resistant to dihydrostreptomycin or oxytetracycline from cheeses produced in Japan (16.7%; P = 0.04). Antimicrobial resistance genes were detected in Enterococcus faecalis (tetL, tetM, and ermB; tetL and ermB; tetM) E. faecium (tetM), Lactococcus lactis (tetS), Lactobacillus (Lb.), casei/paracasei (tetM or tetW), and Lb. rhamnosus (ermB) isolated from seven imported cheeses. Moreover, these E. faecalis isolates were able to transfer antimicrobial resistance gene(s). Although antimicrobial resistance genes were not detected in any LAB isolates from Japanese cheeses, Lb. casei/paracasei and Lb. coryniformis isolates from a Japanese farm‐made cheese were resistant to oxytetracycline (minimal inhibitory concentration [MIC], 32 µg/mL). Leuconostoc isolates from three Japanese farm‐made cheeses were also resistant to dihydrostreptomycin (MIC, 32 to > 512 µg/mL). In conclusion, the present study demonstrated contamination with antimicrobial‐resistant LAB in imported and Japanese farm‐made cheeses on the Japanese market, but not in Japanese commercial cheeses. 相似文献
77.
Ian S. Pearse Kathy Hughes Kaori Shiojiri Satomi Ishizaki Richard Karban 《Oecologia》2013,172(3):869-875
The importance of interplant volatile signaling in plant–herbivore interactions has been a contentious issue for the past 30 years. We revisit willows as the system in which evidence for interplant signaling was originally found, but then questioned. We established three well-replicated experiments with two willow species (Salix exigua and Salix lemmonii) to address whether the receipt of an interplant signal from a neighboring willow reduces herbivore damage. Additionally we tested whether this signal is volatile in nature, and whether plants signal better to themselves than they do to other individuals. In all three experiments, we found evidence that cues from a damaged neighbor reduce subsequent herbivory experienced by willows. In one experiment, we showed that bagging of clipped tissue, which prevents the exchange of volatile signals, removed the effect of neighbor wounding. This was consistent with results from the other two experiments, in which clipping potted neighbors connected only through airborne volatile cues reduced damage of receivers. In one year, we found evidence that the perception of volatile signals from genetically identical clones was more effective at reducing foliar damage to a neighbor than signals from a genetically different individual. However, this trend was not significant in the following year. In three well-replicated experiments, we found strong evidence for the importance of interplant volatile cues in mediating herbivore interactions with willows. 相似文献
78.
79.
Kentaro Takai Yasunao Inoue Yasuko Konishi Atsushi Suwa Yoshiharu Uruno Harumi Matsuda Tomokazu Nakako Mutsuko Sakai Hiroyuki Nishikawa Gakuji Hashimoto Takeshi Enomoto Atsushi Kitamura Yasuaki Uematsu Akihiko Kiyoshi Takaaki Sumiyoshi 《Bioorganic & medicinal chemistry letters》2013,23(16):4644-4647
We designed and synthesized N-substituted 8-azatetrahydroquinolone derivatives as selective M1 and M4 muscarinic acetylcholine receptors agonists. Optimization of selected derivatives led to the discovery of compound 7 as a highly potent M1 and M4 agonist with weak hERG inhibition. Oral administration of compound 7 improved psychosis-like behavior in rats. 相似文献
80.
Yasutoyo Nagai Tetsusaburo Nishikawa 《Bioscience, biotechnology, and biochemistry》2013,77(4):575-584
Chicken feather powder was solubilized by Schweitzer’s reagent with shaking in the presence of air and the soluble feather keratin was prepared by dialyzing this extract against running water. Cystine residues in the starting feather keratin was converted to cysteic acid residues in the solubilized derivatives by air oxygen. Copper was bound fairly tightly to the solubilized protein and this copper-protein complex was separated into four fractions by CM- and DEAE-cellulose column chromatography. Each fraction had varied amount of bound copper, having a broad distribution of the molecular weight between 10,000 and 60,000 Sephadex column chromatographically. Although the amino acid composition of all separated feather keratin fractions were quite similar, the different electrophoretic patterns were observed among them by DISC electrophoresis. 相似文献