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61.
A community of arbuscular mycorrhizal (AM) fungi was investigated in a warm-temperate deciduous broad-leaved forest using
a molecular analysis method. Root samples were obtained from the forest, and DNA was extracted from the samples. Partial 18S
rDNA of AM fungi were amplified from the extracted DNA by polymerase chain reaction using a universal eukaryotic primer NS31
and an AM fungal-specific primer AM1. After cloning the PCR products, 394 clones were obtained in total, which were divided
into five types by restriction fragment length polymorphism (RFLP) with HinfI, RsaI, and Hsp92II. More than 20% of the clones were randomly selected from each RFLP type and sequenced. Phylogenetic analysis showed that
all the obtained clones belonged to Glomus but could not be identified at species level. Topsoil of the forest containing plant roots was inoculated to nonmycorrhizal
seedlings of indigenous woody plants, Rhus javanica var. roxburghii and Clethra barvinervis, to introduce the community of AM fungi into the seedlings. Among these five RFLP types, four types were detected from both
seedlings, which indicates that the AM fungal community in the forest root samples was introduced at least partly into the
seedlings. Meanwhile, an additional four types that were not found in the forest root samples were newly detected in the seedlings,
these types were closely related to one another and close to G. fasciculatum or G. intraradices. It is expected that a community of indigenous diverse AM fungi could be introduced into target fields by planting these
mycorrhizal seedlings. 相似文献
62.
Toshitsugu Kawata Kaoru Tenjou Chiyoko Tokimasa Tadashi Fujita Masato Kaku Akira Matsuki Shinya Kohno Keisuke Tsutsui Junji Ohtani Masahide Motokawa Mao Shigekawa Yuiko Tohma Kazuo Tanne 《Experimental Animals》2004,53(1):47-51
Alendronate, one of the bisphosphonates, is known to have an inhibitory effect on bone resorption. The purpose of this study was to investigate the effects of alendronate on ectopic bone graft resorption and to determine the optimal dose in the mouse. The grafted bone in the control group disappeared due to resorption by osteoclasts within 5 weeks. In the experimental groups, the area of bone tissue decreased by only 20-40% at 5 weeks post-operatively. At 8 and 9 weeks after surgery, the decreased area of bone structure was significantly less in all the 10(-4) M injected alendronate-immersed groups than in the 10(-4) M non-injected alendronate-immersed. At 9 weeks after surgery, the number of osteoclasts were significantly less in the 10(-4) M injected alendronate-treated groups than in the 10(-4) M non-injected alendronate-treated groups. These results suggest that alendronate inhibits resorption of ectopic bone graft at concentrations of 10(-4) and 10(-6) M. 相似文献
63.
Shunpei Sato Hiroyuki Kojima Junko Ando Hironori Ando Richard L. Wilmot Lisa W. Seeb Vladimir Efremov Larry LeClair Wally Buchholz Deuk-Hee Jin Shigehiko Urawa Masahide Kaeriyama Akihisa Urano Syuiti Abe 《Environmental Biology of Fishes》2004,69(1-4):37-50
We examined the genetic population structure of chum salmon, Oncorhynchus keta, in the Pacific Rim using mitochondrial (mt) DNA analysis. Nucleotide sequence analysis of about 500 bp in the variable portion of the 5′ end of the mtDNA control region revealed 20 variable nucleotide sites, which defined 30 haplotypes of three genealogical clades (A, B, and C), in more than 2,100 individuals of 48 populations from Japan (16), Korea (1), Russia (10), and North America (21 from Alaska, British Columbia, and Washington). The observed haplotypes were mostly associated with geographic regions, in that clade A and C haplotypes characterized Asian populations and clade B haplotypes distinguished North American populations. The haplotype diversity was highest in the Japanese populations, suggesting a greater genetic variation in the populations of Japan than those of Russia and North America. The analysis of molecular variance and contingency χ2 tests demonstrated strong structuring among the three geographic groups of populations and weak to moderate structuring within Japanese and North American populations. These results suggest that the observed geographic pattern might be influenced primarily by historic expansions or colonizations and secondarily by low or restricted gene flow between local groups within regions. In addition to the analysis of population structure, mtDNA data may be useful for constructing a baseline for stock identification of mixed populations of high seas chum salmon. 相似文献
64.
Takehara M Ino K Takakusagi Y Oshikane H Nureki O Ebina T Mizukami F Sakaguchi K 《Analytical biochemistry》2008,373(2):322-329
Two kinds of layer silicate powder, Micromica and chlorite, were used to aid protein crystallization by the addition to hanging drops. Using appropriate crystallization buffers, Micromica powder facilitated crystal growth speed for most proteins tested in this study. Furthermore, the addition of Micromica powder to hanging drops allowed the successful crystallization of lysozyme, catalase, concanavalin A, and trypsin even at low protein concentrations and under buffer conditions that otherwise would not generate protein crystals. Except for threonine synthase and apoferritin, the presence of chlorite delayed crystallization but induced the formation of large crystals. X-ray analysis of thaumatin crystals generated by our novel procedure gave better quality data than did that of crystals obtained by a conventional hanging drop method. Our results suggest that the speed of crystal growth and the quality of the corresponding X-ray data may be inversely related, at least for the formation of thaumatin crystals. The effect of Micromica and chlorite powders and the application of layer silicate powder for protein crystallization are discussed. 相似文献
65.
Roles of Four Chitinases (ChiA, ChiB, ChiC, and ChiD) in the Chitin Degradation System of Marine Bacterium Alteromonas sp. Strain O-7 总被引:1,自引:0,他引:1
66.
67.
68.
Inhibitors of protein and nucleic acid synthesis such as puromycin,cycloheximide, 5-fluorodeoxyuridine and 5-fluorouracil havebeen used to study the dark reactions involved in photoregulationof carotenogenesis in Rhodotorula minuta. The results indicatedthat as already reported in other organisms, carotenogenic enzymesare synthesized first and, in turn, synthesize carotenoids inthe dark. Synthesis of the carotenogenic enzymes was absolutelydependent on oxygen and came to an end within 6 hr at 26?C underaerobic conditions. Photoregulation of this synthesis may occurat the translational level. 5-Fluorodeoxyuridine and 5-fluorouracilacted as chemical inducers of carotenogenesis in Rh. minutagrown in the dark. However, the site of the action of thesechemicals was assumed to be different from that of light, becausethe chemical and light effects on the induction of carotenogenesiswere additive. (Received September 16, 1981; Accepted March 3, 1982) 相似文献
69.
Hidekazu Tanaka Takahiro Yamaguchi Kae Hachiya Kazuhiro Miwa Jun Shinoda Masahide Hayashi Shinichi Ogawa Hironori Nishibori Satoshi Goshima Masayuki Matsuo 《Reports of Practical Oncology and Radiotherapy》2018,23(3):215-219
Aim
To define the optimal margin on MRI scans in the re-radiation planning of recurrent glioblastoma using methionine positron emission tomography (MET-PET).Background
It would be very useful if the optimal margin on MRI to cover the uptake area on MET-PET is known.Materials and Methods
CT, MRI, and MET-PET were performed separately over the course of 2 weeks. Among the MRI scans, we used the contrast-enhanced T1-weighted images (Gd-MRI) and T2-weighted images (T2-MRI). The Gd-MRI-based clinical target volume (CTV) (CTV-Gd) and the T2-MRI-based CTV (CTV-T2) were defined as the contrast-enhanced area on Gd-MRI and the high intensity area on T2-MRI, respectively. We defined CTV x mm (x = 5, 10, 15, 20) as x mm outside the CTV. MET-PET-based CTV (CTV-MPET) was defined as the area of accumulation of MET-PET. We calculated the sensitivity and specificity of CTV-Gd and CTV-T2 following comparison with CTV-MPET, which served as the gold standard in this study.Results
The sensitivity of CTV-T2 5 mm (98%) was significantly higher than CTV-T2 (87%), and there was no significant difference in the sensitivity between CTV-T2 5 mm and CTV T2 10, 15, or 20 mm. The sensitivity of CTV-Gd 20 mm (97%) was lower than that of CTV-T2 5 mm (98%).Conclusions
A margin of at least 5 mm around the high intensity area on T2-MRI is necessary in the target volume delineation of recurrent glioblastoma for the coverage of MET-PET findings in re-radiation therapy planning. 相似文献70.
Hidekazu Tanaka Takahiro Yamaguchi Kae Hachiya Shingo Kamei Satoshi Ishihara Masahide Hayashi Shinichi Ogawa Hironori Nishibori Satoshi Goshima Masayuki Matsuo 《Reports of Practical Oncology and Radiotherapy》2018,23(1):28-33