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161.
Takashi Misawa Mitsuyoshi Imamura Yuto Ozawa Kazuchika Haishima Masaaki Kurihara Yutaka Kikuchi Yosuke Demizu 《Bioorganic & medicinal chemistry letters》2017,27(17):3950-3953
Lysine-based amphipathic nonapeptides, including homochiral peptides [Ac-(l-Lys-l-Lys-Xaa)3-NH2 (Xaa = Gly, Ala, Aib, Ac5c, or Ac6c) and Ac-(d-Lys-d-Lys-Aib)3-NH2], a heterochiral peptide [Ac-(l-Lys-d-Lys-Aib)3-NH2], and a racemic mixture of diastereomeric peptides [Ac-(rac-Lys-rac-Lys-Aib)3-NH2] were designed and synthesized to investigate the relationship between their preferred secondary structures and their antimicrobial activity. Peptide 5, [Ac-(l-Lys-l-Lys-Ac6c)3-NH2] formed a stable α-helical structure and exhibited strong activity against Gram-negative bacteria (Escherichia coli and Pseudomonas aeruginosa). 相似文献
162.
Junji Kobayashi Kouji Shirai Takeyoshi Murano Yoshiki Misawa Jun Tashiro Tomohiko Yoshida Masaki Shinomiya 《Biochimica et Biophysica Acta (BBA)/Molecular and Cell Biology of Lipids》2002,1583(1):117-121
In this study, we present clinical feature of a novel case with homozygous apolipoprotein (apo) E5.The patient was a 53-year-old Japanese woman. She was from a small island off the coast of Kagoshima Prefecture, Japan. Her parents were first degree cousins. No corneal opacification, xanthomatosis, lymphadenopathy, or hepatosplenomegaly was observed. There have been no signs of clinically overt atherosclerosis to date. Her serum total cholesterol, triglycerides (TG) and high-density lipoprotein (HDL)-cholesterol levels were 11.6, 6.1 and 1.2 mmol/l, respectively, and apo A-I, A-II, B, C-II, C-III and E levels were 121, 34.8, 269, 10.4, 25.7 and 10.3 mg/dl, respectively. Serum lipoprotein profile analyzed by agarose gel electrophoresis and differential staining revealed markedly increased cholesterol and TG in both β and preβ-migrated lipoproteins, whereas α-migrated lipoprotein showed decreased cholesterol. Her apo E isoform analyzed by isoelectric focusing (IEF) was found to be homozygous apo E5.Polymerase chain reaction restriction fragment length polymorphism (PCR-RFLP) analysis of her apo E and lipoprotein lipase (LPL) genes revealed that she had a homozygous apo E (Glu3→Lys) and heterozygous LPL variant Ser447 to Ter. Her son and daughter, both of whom had hyperlipidemia, were found to have apo E3/5 phenotype. Direct sequencing analysis of her apo E gene confirmed a homozygous one nucleotide change: G to A at nucleotide position of 2836 in the exon 3, resulting in Glu3→Lys mutation.This is the first report of lipids and lipoprotein profiles in patients with homozygous apo E5 (Glu3→Lys). 相似文献
163.
164.
Plant cell cultures are potentially rich sources of valuable pharmaceuticals and other biologically active phytochemicals, but relatively few cultures synthesize secondary compounds over extended periods in amounts comparable to those found in the whole plant. Frequently, no secondary metabolites characteristic of the intact plant are produced. So far, the manipulation of culture media, culture conditions and phytohormone levels have, in general, failed to permit commercial production of those phytochemicals useful in medicine and industry. This almost certainly reflects the lack of understanding of basic secondary metabolic regulation in cultured plant cells.
Microbial insult can induce antibiotic phytochemical synthesis in cultured plant cells: the microbial molecules which stimulate synthesis have been called ‘elicitors’. Increased synthesis of secondary products in response to elicitation of various types appear to be the general response of cultured cells. This paper illustrates the immense biotechnological potential of plant cell culture—‘elicitor’ (inducer) interactions to the large scale production of secondary metabolites, and suggests several lines of enquiry that remain to be authoritatively treated. 相似文献
165.
Kanji Ohyama Yuko Uchida Norihiko Misawa Tohru Komano Minoru Fujita Tamio Ueno 《Plant cell reports》1984,3(1):21-22
The culture of cells of Euphorbia tirucalli L. resulted in the formation of intracellular particles which osmium tetroxide staining and electron microscopy indicated to be oil bodies. Chemical analysis (TLC, HPLC, GLC and GC-MS) disclosed steroids, triterpenoids, and diterpenoids as the major oil components of the cultured cells. 相似文献
166.
167.
The Erwinia uredovora crtB, crtE, crtI, and crtY genes required for beta-carotene biosynthesis were introduced by conjugal transfer into an ethanol-producing bacterium, Zymomonas mobilis, and a phytopathogenic bacterium, Agrobacterium tumefaciens, in which no carotenoid is synthesized. The transconjugants of Z. mobilis and A. tumefaciens carrying these genes appeared as yellow colonies and produced 220 and 350 micrograms of beta-carotene per g of dry weight, respectively, in the stationary phase in liquid culture. 相似文献
168.
Hideo Kobayashi Kouji Matsumoto Satoru Misawa Kin-ichiro Miura Hideo Hirokawa 《Molecular & general genetics : MGG》1989,220(1):8-11
Summary The amino acid sequence, arginine-glycine-aspartic acid (RGD), found in some cell adhesive proteins, is a recognition signal for the receptor protein. It is interesting that we have found the RGD sequence in terminal protein (TP) of bacteriophages 29 and M2 near an amino acid, the serine residue at 232, covalently linked to the terminal nucleotide of their DNAs. At the initiation of proteinprimed DNA replication, TP is essential for the recognition of replication machinery containing DNA polymerase and primer protein (PP; PP becomes TP upon linking the first nucleotide, and hence the primary structure of TP is the same as that of PP). Synthetic peptide RGD specifically inhibited transfection of 29 and M2. The target of the RGD peptide is shown to be TP by marker rescue experiments, suggesting that a receptor for the RGD sequence exists in TP. Furthermore, the peptide inhibited the in vitro protein-priming reaction of DNA replication. We propose that the RGD sequence of PP and a putative receptor on TP is utilized for the molecular recognition initiating DNA replication. 相似文献
169.
The kyotorphin (tyrosine-arginine) receptor and a selective reconstitution with purified Gi, measured with GTPase and phospholipase C assays 总被引:3,自引:0,他引:3
H Ueda Y Yoshihara H Misawa N Fukushima T Katada M Ui H Takagi M Satoh 《The Journal of biological chemistry》1989,264(7):3732-3741
We attempted to identify the kyotorphin receptor and the post receptor mechanisms mediated by GTP-binding proteins (G-proteins), using reconstitution techniques. The specific binding of [3H]kyotorphin in rat brain membranes was composed of high affinity (Kd = 0.34 nM) and low affinity (Kd = 9.07 nM) binding. As the high affinity binding disappeared in the presence of guanosine 5'-O-(3-thiotriphosphate) and MgCl2, we investigated the kyotorphin receptor-mediated changes in membrane G-protein activity by measuring low Km GTPase activity. Kyotorphin produced a stimulation of low Km GTPase, and this stimulation was antagonized by Leu-Arg, a synthetic dipeptide which showed a potent displacement of [3H]kyotorphin binding, yet in itself had no effect on the low Km GTPase. The kyotorphin stimulation of low Km GTPase was abolished by pretreating membranes with islet-activating protein, pertussis toxin, and was recovered by reconstitution with purified G-protein, Gi, but not with Go. Similar evidence of selective coupling of kyotorphin receptor to Gi was obtained with the phospholipase C assay. Kyotorphin-induced stimulation of phospholipase C was also abolished by islet-activating protein-treatment and recovered by reconstitution with Gi but not with Go. These findings indicate that specific high and low affinity kyotorphin receptors exist in the rat brain and that the kyotorphin receptor is functionally coupled to stimulation of phospholipase C, through Gi. This study provides the first evidence of a selective involvement of Gi in the receptor-mediated activation of phospholipase C. 相似文献
170.
Regulation of Organ Formation by Cytokinin and Auxin in Lilium Bulbscales Grown In Vitro 总被引:1,自引:0,他引:1
Regulation of organ formation by cytokinin and auxin was investigatedin vitro using Lilium auratum Lindl. (wild species habituatedin Japan) and Lilium speciosum Thunb. cv. "Uchida". The interactionof -naphthylacetic acid (NAA) and kinetin on bulbscale or rootdifferentiation was examined. NAA and kinetin showed mainlyindividual but also some synergistic effects. The effects ofbenzyladenine (BA) and kinetin were compared and the resultindicated that BA has a stronger physiological effect on organformation than kinetin and that their effects on Lilium auratumand Lilium speciosum were BA or kinetin-specific. The actionof kinetin on Lilium was affected by sucrose concentration andthe strength of the Murashige and Skoog medium (MS medium),and thus their high concentrations inhibited the kinetin-inducedbulbscale differentiation. Furthermore, a high sucrose levelnegated the kinetin inhibition of root formation, while highMS medium strength in itself inhibited root formation. Morphologicalobservation of bulbscale differentiation induced under a highkinetin level revealed that the new-formed structures are homologousto normally grown bulbs in soil in spite of their particularfeatures. (Received August 3, 1981; Accepted November 2, 1981) 相似文献