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281.
Yayoi Kamata Aya Taniguchi Mami Yamamoto Junko Nomura Kazuhiko Ishihara Hidenari Takahara Toshihiko Hibino Atsushi Takeda 《The Journal of biological chemistry》2009,284(19):12829-12836
Filaggrin is a component of the cornified cell envelope and the precursor
of free amino acids acting as a natural moisturizing factor in the stratum
corneum. Deimination is critical for the degradation of filaggrin into free
amino acids. In this study, we tried to identify the enzyme(s) responsible for
the cleavage of deiminated filaggrin in vitro. First, we investigated
citrulline aminopeptidase activity in the extract of newborn rat epidermis by
double layer fluorescent zymography and detected strong activity at neutral
pH. Monitoring the citrulline-releasing activity, we purified an enzyme of 280
kDa, comprised of six identical subunits of 48 kDa. The NH2
terminus of representative tryptic peptides perfectly matched the sequence of
rat bleomycin hydrolase (BH). The enzyme released various amino acids except
Pro from β-naphthylamide derivatives and hydrolyzed
citrulline-β-naphthylamide most effectively. Thus, to break down
deiminated filaggrin, another protease would be required. Among proteases
tested, calpain I degraded the deiminated filaggrin effectively into many
peptides of different mass on the matrix-assisted laser
desorption/ionization-time of flight mass spectrum. We confirmed that various
amino acids including citrulline were released by BH from those peptides. On
the other hand, caspase 14 degraded deiminated filaggrin into a few peptides
of limited mass. Immunohistochemical analysis of normal human skin revealed
co-localization of BH and filaggrin in the granular layer. Collectively, our
results suggest that BH is essential for the synthesis of natural moisturizing
factors and that calpain I would play a role as an upstream protease in the
degradation of filaggrin.The mammalian epidermal keratinocytes arise from proliferating basal cells
and move outward through a series of distinct differentiation events to form
the stratum corneum (1,
2). During this progressive
epidermal differentiation, keratinocytes express different proteins such as
keratins, profilaggrin/filaggrin, involucrin, small proline-rich proteins,
loricrin, cystatin A, and elafin, which form the cornified envelope of mature
corneocytes
(3–7).
Profilaggrin is synthesized as a large, extremely insoluble phosphoprotein
that consists of a unique NH2-terminal Ca2+-binding
protein of the S-100 family, linked to 10–20 tandem filaggrin monomer
repeats
(8–10).
Each individual filaggrin repeat is completely removed by proteolysis to
generate the mature filaggrin monomer (a molecular mass of 37 kDa in human).
Then, filaggrin is completely degraded in the uppermost layer of the stratum
corneum to produce a mixture of free and modified hygroscopic amino acids that
are important for maintaining epidermal hydration
(2,
11–13).
In addition, a number of proteins are subjected to various post-translational
modifications such as disulfide bonding, N-(γ-glutamyl)-lysine
isopeptide cross-linking, and deimination during the terminal differentiation
of epidermal keratinocytes (4,
6,
14,
15). Deimination is catalyzed
by peptidylarginine deiminase
(PAD),2 which converts
arginine to citrulline in proteins
(17–19).
The modification seems essential for the processing into free amino acids
including citrulline.Several proteases reportedly participate in the processing of profilaggrin.
Furin, a member of the proprotein convertase family, has been proposed to
cleave the NH2 terminus of profilaggrin, facilitating the release
of the NH2-terminal S-100 protein
(20,
21). In contrast, calpain I
and profilaggrin endopeptidase I (PEP-I) were implicated in the processing of
the linker regions between the filaggrin monomer repeats to generate the
filaggrin monomer
(22–25).
Recently, significant results regarding the conversion of profilaggrin to
filaggrin have been obtained with the knock-out of matriptase/MT-SP1,
prostasin/channel-activating serine protease 1/Prss 8, and caspase 14
in mice
(26–28).
These proteases were a key component of the profilaggrin-processing pathway in
terminal epidermal differentiation. However, although the signal initiating
the degradation of profilaggrin at a defined stage of the maturation of the
stratum corneum was found to be the water gradient within the stratum corneum
itself (11), the proteases for
the processing of filaggrin and/or the deiminated form into peptides following
the breakdown of these peptides to amino acids including citrulline remain
unknown.In this study, we have purified a novel aminopeptidase using a deiminated
substrate from rat skin homogenate and identified it as a neutral cysteine
protease, bleomycin hydrolase (BH). Furthermore, we investigated the
processing of the deiminated filaggrin by calpain I or caspase 14. Based on
these results, we proposed that calpain I participated preferentially in the
processing of deiminated filaggrin into peptides and then BH appeared
essential for the breakdown of the peptides into amino acids. 相似文献
282.
283.
1-Pentyl, 1-hexyl and 1-heptyl ferulates were continuously synthesized at 60–90°C using a reactor system in which a column packed with ferulic acid powders and another column packed with immobilized Candida antarctica lipase particles were connected in series. Conversions greater than 0.9 were achieved for the synthesis of the 1-hexyl and 1-heptyl ferulates at 90°C. The system could be stably operated for the 1-heptyl ferulate synthesis at 90°C for at least two weeks. 相似文献
284.
Hosokawa Keizo Matsuki Rikyu Oikawa Yayoi Yamamura Saburo 《Plant Cell, Tissue and Organ Culture》1997,51(2):137-140
Leaf sections of greenhouse-grown Miscanthus x ogiformis Honda 'Giganteus' plants and leaf sections or shoot apices of in
vitro shoot cultures were grown on Murashige and Skoog medium containing various concentrations of benzyladenine (BA) and
2,4-dichlorophenoxyacetic acid. On leaf sections, the callus induction decreased with increasing BA concentration. The percentage
of embryogenic callus was increased, the percentage of root-forming callus decreased, and a new shoot-forming callus type
was formed by inclusion of BA during callus induction. A higher percentage of shoot-forming callus was formed on shoot apices
compared with leaf sections of in vitro-grown shoots when cultured on 0.4 μM BA. The largest number of plants per callus piece
was regenerated from shoot-forming callus, but maintenance of the high regeneration capacity proved difficult.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
285.
We present confirmation of the experimental penetration of Trichophyton mentagrophytes into human stratum corneum under designated
conditions of temperature and humidity. When stratum corneum, obtained from healthy human heel region, was incubated at 100%
humidity, mycelium was observed in the corneum layer on day 2 at 35 °C and 27 °C, and on day 4 at 15 °C. At 90% humidity,
the hyphae penetrated into the stratum corneum on day 4 at 35 °C, and on day 6 at 27 °C. Whereas, at 80% humidity, no fungal
elements were observed in the stratum corneum at both 27 °C and 35 °C for up to 7 day. These data suggested that humidity
was a more important environmental factor for penetration than temperature, and that at least 90% humidity is necessary for
dermatophytes to penetrate into the stratum corneum within a few days. Mean humidity in the interdigital space between the
fourth and fifth toes was found to be approximately 98%.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
286.
Peeva Stanislava Raichev Evgeniy Georgiev Dilian Yankov Yanko Tsunoda Hiroshi Kaneko Yayoi 《Journal of Ethology》2023,41(1):15-24
Journal of Ethology - Illumination at night is determined by moon phase, naturally affecting the reproductive activities of nocturnal animals. The European badger (Meles meles Linnaeus, 1758) is a... 相似文献
287.
Yayoi Kagami Yuko Mogi Tatsushi Arai Manami Yamamoto Kazuyoshi Kuwano Shigeyuki Kawano 《Journal of phycology》2008,44(3):691-702
Ulva compressa L. is a heterothallic macroalga considered to be in the early evolutionary stage between isogamy and anisogamy. Two genetic lines of this species, each consisting of gametophytes with opposite mating types, were collected on the coasts of Ehime and Iwate prefectures: MGEC‐1 (mt+) and MGEC‐2 (mt?) from Ehime, and MGEC‐5 (mt+) and MGEC‐6 (mt?) from Iwate. Their relative gamete sizes (i.e., cell volumes) do not correspond to their mating types: MGEC‐6 (19.8 μm3) > MGEC‐1 (18.6 μm3) > MGEC‐5 (17.0 μm3) > MGEC‐2 (10.1 μm3). The pattern of organelle inheritance is an important sexual characteristic in many eukaryotes. We therefore investigated the relationship between gamete size and the inheritance of chloroplast DNA (cpDNA). Polymorphisms between the cpDNA of the two lines were used as markers. We found a 24 bp insertion between psbF and psbL, and the substitution of a StyI site (from C CAAGG to T CAAGG) in the intergenic region between petD and accD. Two interline crosses (MGEC‐1 × MGEC‐6 and MGEC‐2 × MGEC‐5) produced 42 and 38 zygotes, respectively. PCR and PCR–RFLP analyses showed that the cpDNA of the mt+ gametes was consistently inherited in both crosses. The cpDNA is inherited from one parent only, and it depends not on gamete size but on being mt+. The cpDNA was observed during crossing and in the zygotes 6 h after mating. In 6% of the zygotes, the cpDNA derived from the mt? gametes disappeared 3–4 h after mating. Preferential digestion of the cpDNA in the zygote’s mt? gamete may form the basis for uniparental inheritance of cpDNA. 相似文献
288.
289.
Mori T Kitano K Terawaki S Maesaki R Fukami Y Hakoshima T 《The Journal of biological chemistry》2008,283(43):29602-29612
CD44 is an important adhesion molecule that functions as the major hyaluronan receptor which mediates cell adhesion and migration in a variety of physiological and pathological processes. Although full activity of CD44 requires binding to ERM (ezrin/radixin/moesin) proteins, the CD44 cytoplasmic region, consisting of 72 amino acid residues, lacks the Motif-1 consensus sequence for ERM binding found in intercellular adhesion molecule (ICAM)-2 and other adhesion molecules of the immunoglobulin superfamily. Ultracentrifugation sedimentation studies and circular dichroism measurements revealed an extended monomeric form of the cytoplasmic peptide in solution. The crystal structure of the radixin FERM domain complexed with a CD44 cytoplasmic peptide reveals that the KKKLVIN sequence of the peptide forms a beta strand followed by a short loop structure that binds subdomain C of the FERM domain. Like Motif-1 binding, the CD44 beta strand binds the shallow groove between strand beta5C and helix alpha1C and augments the beta sheet beta5C-beta7C from subdomain C. Two hydrophobic CD44 residues, Leu and Ile, are docked into a hydrophobic pocket with the formation of hydrogen bonds between Asn of the CD44 short loop and loop beta4C-beta5C from subdomain C. This binding mode resembles that of NEP (neutral endopeptidase 24.11) rather than ICAM-2. Our results reveal a characteristic versatility of peptide recognition by the FERM domains from ERM proteins, suggest a possible mechanism by which the CD44 tail is released from the cytoskeleton for nuclear translocation by regulated intramembrane proteolysis, and provide a structural basis for Smad1 interactions with activated CD44 bound to ERM protein. 相似文献
290.
Shoichi Katsuta Yudai Iwabe Yayoi Kato Yoshihiro Kudo Yasuyuki Takeda 《Inorganica chimica acta》2008,361(1):103-108
The solvent extraction properties of macrocyclic trinuclear organometallic complexes, [(p-cymene)Ru(pyO2)]3 and [Cp∗Rh(pyO2)]3, for Li+, Na+, and K+ picrates have been investigated in a dichloromethane-water system at 25 °C. The extraction rates of the alkali metal picrates with these macrocyclic complex ligands are unusually slow; the shaking times required to attain equilibrium are at least 1 h for [(p-cymene)Ru(pyO2)]3 and 20-40 h for [Cp∗Rh(pyO2)]3. From analysis of the equilibrium data, the extraction constants (Kex = [ML+A−]o/[M+][L]o[A−]; M+ = alkali metal ion, L = macrocyclic ligand, A− = picrate ion, o = organic phase) have been determined. The log Kex value varies in the sequences, Li+ (5.72) > Na+ (4.50) > K+ (2.88) for [(p-cymene)Ru(pyO2)]3 and Li+ (4.79) > Na+ (2.70) ≈ K+ (2.69) for [Cp∗Rh(pyO2)]3. The Kex values of 6,6-dibenzyl-14-crown-4 (DBz14C4), which is one of the best Li+-selective crown ethers, have also been determined for comparison. It is revealed that [Cp∗Rh(pyO2)]3 is much superior to DBz14C4 both in the extractability for Li+ and the selectivity for Li+ over Na+. 相似文献