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81.
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83.
S. Handa Y. Matsumoto J. Nakayama N. Handa N. Hattori T. Taki 《Glycoconjugate journal》1993,10(4):318
84.
85.
Yuichi?YamauraEmail author J.?Andrew?Royle Naoaki?Shimada Seigo?Asanuma Tamotsu?Sato Hisatomo?Taki Shun’ichi?Makino 《Biodiversity and Conservation》2012,21(6):1365-1380
Since the 1960s, Japan has become highly dependent on foreign countries for natural resources, and the amount of managed lands
(e.g. coppice, grassland, and agricultural field) has declined. Due to infrequent natural and human disturbance, early-successional
species are now declining in Japan. Here we surveyed bees, birds, and plants in four human-disturbed open habitats (pasture,
meadow, young planted forest, and abandoned clear-cut) and two forest habitats (mature planted forest and natural old-growth).
We extended a recently developed multispecies abundance model to accommodate count data, and used the resulting models to
estimate species-, functional group-, and community-level state variables (abundance and species richness) at each site, and
compared them among the six habitats. Estimated individual-level detection probability was quite low for bee species (mean
across species = 0.003; 0.16 for birds). Thirty-two (95% credible interval: 13–64) and one (0–4) bee and bird species, respectively,
were suggested to be undetected by the field survey. Although habitats in which community-level abundance and species richness
was highest differed among taxa, species richness and abundance of early-successional species were similar in the four disturbed
open habitats across taxa except for plants in the pasture habitat which was a good habitat only for several exotic species.
Our results suggest that human disturbance, especially the revival of plantation forestry, may contribute to the restoration
of early-successional species in Japan. 相似文献
86.
Pituitary adenylate cyclase-activating peptide (PACAP) is known to regulate not only neurons but also astrocytes. Here, we investigated, both in vitro and in vivo, the effects of PACAP38 on rat Müller cells, which are the predominant glial element in the retina. Müller cells isolated from juvenile Wistar rats were treated with PACAP38 or PACAP6-38, a PACAP selective antagonist. Cell proliferation was determined by measuring the incorporation of bromodeoxyuridine with ELISA. Interleukin-6 (IL-6) levels in the culture medium were determined by a bioassay using B9 cells, IL-6 dependent hybridoma. In adult Wistar rats, the expression of IL-6 in the retina after intravitreal injection of PACAP38 (10 pmol) was assessed by immunohistochemistry. PACAP38 stimulated IL-6 production in Müller cells at a concentration as low as 10(-12) M, which did not induce cell proliferation. This elevation of IL-6 production was inhibited by PACAP6-38. Radial IL-6 expression was observed throughout the retina at 2 and 3 days after PACAP38 injection. These data demonstrate that Müller cells are one of the target cells for PACAP. IL-6, which is released from Müller cells with stimulation by PACAP, may play a significant role in the retina. 相似文献
87.
Chiu YC Okajima T Murakawa T Uchida M Taki M Hirota S Kim M Yamaguchi H Kawano Y Kamiya N Kuroda S Hayashi H Yamamoto Y Tanizawa K 《Biochemistry》2006,45(13):4105-4120
Copper amine oxidase contains a post-translationally generated quinone cofactor, topa quinone (TPQ), which mediates electron transfer from the amine substrate to molecular oxygen. The overall catalytic reaction is divided into the former reductive and the latter oxidative half-reactions based on the redox state of TPQ. In the reductive half-reaction, substrate amine reacts with the C5 carbonyl group of the oxidized TPQ, forming the substrate Schiff base (TPQ(ssb)), which is then converted to the product Schiff base (TPQ(psb)). During this step, an invariant Asp residue with an elevated pKa is presumed to serve as a general base accepting the alpha proton of the substrate. When Asp298, the putative active-site base in the recombinant enzyme from Arthrobacter globiformis, was mutated into Ala, the catalytic efficiency dropped to a level of about 10(6) orders of magnitude smaller than the wild-type (WT) enzyme, consistent with the essentiality of Asp298. Global analysis of the slow UV/vis spectral changes observed during the reductive half-reaction of the D298A mutant with 2-phenylethylamine provided apparent rate constants for the formation and decay of TPQ(ssb) (k(obs) = 4.7 and 4.8 x 10(-4) s(-1), respectively), both of which are markedly smaller than those of the WT enzyme determined by rapid-scan stopped-flow analysis (k(obs) = 699 and 411 s(-1), respectively). Thus, Asp298 plays important roles not only in the alpha-proton abstraction from TPQ(ssb) but also in other steps in the reductive half-reaction. X-ray diffraction analyses of D298A crystals soaked with the substrate for 1 h and 1 week revealed the structures of TPQ(ssb) and TPQ(psb), respectively, as pre-assigned by single-crystal microspectrophotometry. Consistent with the stereospecificity of alpha-proton abstraction, the pro-S alpha-proton of TPQ(ssb) to be abstracted is positioned nearly perpendicularly to the plane formed by the Schiff-base imine double bond conjugating with the quinone ring of TPQ, so that the orbitals of sigma and pi electrons maximally overlap in the conjugate system. More intriguingly, the pro-S alpha proton of the substrate is released stereospecifically even in the reaction catalyzed by the base-lacking D298A mutant. On the basis of these results, we propose that the stereospecificity of alpha-proton abstraction is primarily determined by the conformation of TPQ(ssb), rather than the relative geometry of TPQ and the catalytic base. 相似文献
88.
Shinozuka T Shimada K Matsui S Yamane T Ama M Fukuda T Taki M Naito S 《Bioorganic & medicinal chemistry letters》2006,16(6):1502-1505
We have designed and synthesized a novel series of 3-biphenylamino acid amides as cathepsin K inhibitors based on compound I. In these inhibitors, we have discovered 4-aminophenoxyacetic acids 43 and 47 with good IC(50) values, although lipophilic groups are favorable for the hydrophobic S1' pocket. 相似文献
89.
Furubayashi T Ushiyama A Terao Y Mizuno Y Shirasawa K Pongpaibool P Simba AY Wake K Nishikawa M Miyawaki K Yasuda A Uchiyama M Yamashita HK Masuda H Hirota S Takahashi M Okano T Inomata-Terada S Sokejima S Maruyama E Watanabe S Taki M Ohkubo C Ugawa Y 《Bioelectromagnetics》2009,30(2):100-113
To investigate possible health effects of mobile phone use, we conducted a double-blind, cross-over provocation study to confirm whether subjects with mobile phone related symptoms (MPRS) are more susceptible than control subjects to the effect of electromagnetic fields (EMF) emitted from base stations. We sent questionnaires to 5,000 women and obtained 2,472 valid responses from possible candidates; from these, we recruited 11 subjects with MPRS and 43 controls. There were four EMF exposure conditions, each of which lasted 30 min: continuous, intermittent, and sham exposure with and without noise. Subjects were exposed to EMF of 2.14 GHz, 10 V/m (W-CDMA), in a shielded room to simulate whole-body exposure to EMF from base stations, although the exposure strength we used was higher than that commonly received from base stations. We measured several psychological and cognitive parameters pre- and post-exposure, and monitored autonomic functions. Subjects were asked to report on their perception of EMF and level of discomfort during the experiment. The MPRS group did not differ from the controls in their ability to detect exposure to EMF; nevertheless they consistently experienced more discomfort, regardless of whether or not they were actually exposed to EMF, and despite the lack of significant changes in their autonomic functions. Thus, the two groups did not differ in their responses to real or sham EMF exposure according to any psychological, cognitive or autonomic assessment. In conclusion, we found no evidence of any causal link between hypersensitivity symptoms and exposure to EMF from base stations. 相似文献
90.
Embryoid bodies (EBs) are primitive embryonic structures derived from differentiating embryonic stem cells (ESCs). Many techniques
have been used to obtain EBs. Improving the technique of EB formation can help in achieving better results in ESCs differentiation
into neurons, myocardiocytes, haemopoeitic cells, and others. We evaluated the use of Sigmacote™ as a hydrophobic substrate
to improve EB formation. CCE and P19 cell lines were used to obtain EBs and retinoic acid was used to induce neural differentiation.
The results revealed that Sigmacote™, as a hydrophobic substrate, can improve EB formation from ESCs. Our results demonstrate
that the silicon-coating of glass petri dishes by Sigmacote™ is an easy and reproducible technique to enhance EB formation
from murine ESCs and EC cells. 相似文献