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81.
Degradation of focal adhesion proteins during nocodazole-induced apoptosis in rat-1 cells 总被引:4,自引:0,他引:4
Kook S Shim SR Kim JI Ahnn JH Jung YK Paik SG Song WK 《Cell biochemistry and function》2000,18(1):1-7
Nocodazole, a microtubule-disrupting agent, induced apoptosis in Rat-1 cells, as indicated by changes in cell morphology, DNA fragmentation, and eventual cell death. During nocodazole-induced apoptosis, normally flat cells became rounded in shape and detached from the extracellular matrix. These morphological changes appeared to be closely associated with degradation of focal adhesion proteins, including p130cas, p125(FAK) and paxillin. p130cas was also degraded in cells treated with staurosporine or etoposide, suggesting that degradation of focal adhesion proteins is a characteristic feature of apoptosis. Nocodazole-induced apoptosis was antagonized by Bcl-2: degradation of focal adhesion proteins was suppressed and cell viability was enhanced in bcl-2 over-expressing cells, even in the presence of nocodazole. Further study of the molecular mechanism of Bcl-2 activation should provide an understanding of the apoptosis induced by disruption of the microtubule network. 相似文献
82.
Y K Paik J M Trzaskos A Shafiee J L Gaylor 《The Journal of biological chemistry》1984,259(21):13413-13423
The membrane-bound enzyme of microsomes that catalyzes NADPH-dependent reduction of the 14-double bond of conjugated delta 8,14- and delta 7,14-sterols has been studied both as collected in microsomes from broken cell preparations of rat liver and after solubilization. Optimal incubation conditions for assay of the membrane-bound enzyme have been determined, and properties of the microsomal enzyme have been established with respect to cofactor requirements, kinetics, pH, addition of inhibitors, addition of glycerol phosphatides, and sterol substrate specificity. The 14-reductase is readily solubilized with a mixture of octylglucoside and taurodeoxycholic acid. The solubilized enzyme has been enriched by precipitation with polyethylene glycol and chromatography on DEAE-Sephacel and hydroxylapatite columns. The resulting partially purified enzyme has been obtained free of other microsomal enzymes of cholesterol biosynthesis: 4-methyl sterol oxidase, delta 5,7-sterol 7-reductase, delta 8,24-sterol 24-reductase, 3-ketosteroid reductase, and steroid 8----7-ene isomerase, plus microsomal cytochrome P-450, cytochrome P-450 reductase, cytochrome b5 reductase, and cytochrome b5. The partially purified enzyme is stimulated by addition of phospholipids. All of the properties exhibited by partially purified 14-reductase are consistent with the suggestion that the solubilized and enriched enzyme catalyzes the microsomal reduction of the 14-double bond of the sterol-conjugated dienes. However, presence of the enzyme does not prove that the sterol-conjugated dienes are obligatory precursors of cholesterol. 相似文献
83.
Jingpei Piao Jae-Young Lee Jin Bae Weon Choong Je Ma Hyun-Jeong Ko Dae-Duk Kim Wie-Soo Kang Hyun-Jong Cho 《PloS one》2015,10(4)
Oral solid formulations based on Angelica gigas Nakai (AGN) and Soluplus were prepared by the hot-melting extrusion (HME) method. AGN was pulverized into coarse and ultrafine particles, and their particle size and morphology were investigated. Ultrafine AGN particles were used in the HME process with high shear to produce AGN-based formulations. In simulated gastrointestinal fluids (pH 1.2 and pH 6.8) and water, significantly higher amounts of the major active components of AGN, decursin (D) and decursinol angelate (DA), were extracted from the HME-processed AGN/Soluplus (F8) group than the AGN EtOH extract (ext) group (p < 0.05). Based on an in vivo pharmacokinetic study in rats, the relative oral bioavailability of decursinol (DOH), a hepatic metabolite of D and DA, in F8-administered mice was 8.75-fold higher than in AGN EtOH ext-treated group. In scopolamine-induced memory-impaired mice, F8 exhibited a more potent cognitive enhancing effect than AGN EtOH ext in both a Morris water maze test and a passive avoidance test. These findings suggest that HME-processed AGN/Soluplus formulation (F8) could be a promising therapeutic candidate for memory impairment. 相似文献
84.
Jeong-Whun Kim Gwang Lee Seung-Min Moon Myung-June Park Sung Kyu Hong Young-Hwan Ahn Kyoung-Rae Kim Man-Jeong Paik 《Metabolomics : Official journal of the Metabolomic Society》2010,6(2):202-206
Metabolomic analysis of urinary amino acids (AAs) from patients with bladder cancer was performed by gas chromatography–mass
spectrometry. The β-aminoisobutyric acid (P < 0.05) and pyroglutamic acid (P < 0.03) levels among 21 AAs had relatively low P-values in the cancer group. The distorted star pattern of the cancer group was different from the heneicosagonal shape of
the control mean. The present metabolomic screening combined with star pattern recognition method as clinical monitoring tool
might be useful for the visual discrimination of bladder cancer group from normal group. 相似文献
85.
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87.
Although the field of protein methylation enjoys widespread interest in the scientific literature of today, this is a recent phenomenon. Papers on 'protein methylation' were first published in the 1960s. By the early 1980s, it was known that lysine, arginine, histidine and dicarboxylic amino acids were post-translationally methylated by highly specific methyltransferases. However, despite these early advances, the biological importance of these reactions remained largely unproven. With the introduction of modern molecular biology techniques in the mid-1990s, an enormous surge of interest in protein methylation occurred. It is now clear that protein methylation carries many important biological functions, including gene regulation and signal transduction. Thus, the story of protein-methylation research is a testament to both modern molecular biology and the importance of continuing to pursue lines of research in which the precise biological function might not be currently known. 相似文献
88.
Summary. Cervical cancer is one of the leading causes of female cancer death worldwide with about 500,000 deaths per year. Both mitomycin
C and cisplatin are alkylating agents, which bind and intercalate DNA, and thus used as anti-cancer drugs. In these studies,
we focused on investigating the apoptotic effects of intercalating agents on HPV-negative cervical cancer C-33A cells. Accordingly,
C-33A cells were treated with carboplatin, mitomycin C or cisplatin. Cell cycle analysis revealed that treatment with mitomycin
C and cisplatin but not with carboplatin resulted in apoptosis. Both mitomycin C and cisplatin induced apoptosis in C-33A
cells via caspase-8 and -3 processing in a Fas/FasL-dependent manner and also suppressed IL-18 expression, while they down-regulated
IκB expression and up-regulated p65 expression. These results suggest that both mitomycin C and cisplatin induce apoptosis,
not only via the caspase-8 and -3 dependent Fas/FasL pathway, but also via the regulation of NF-κB activity and IL-18 expression
in HPV-negative cervical cancer C-33A cells. 相似文献
89.
Live cell imaging compatible immobilization of Chlamydomonas reinhardtii in microfluidic platform for biodiesel research 下载免费PDF全文
90.