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171.
Pyrrole derivatives as potent inhibitors of lymphocyte-specific kinase: Structure,synthesis, and SAR
Tetsuo Takayama Hiroki Umemiya Hideaki Amada Tetsuya Yabuuchi Fumiyasu Shiozawa Hironori Katakai Akiko Takaoka Akie Yamaguchi Mayumi Endo Masakazu Sato 《Bioorganic & medicinal chemistry letters》2010,20(1):108-111
We have described the synthesis, enzyme inhibitory activity, structure–activity relationships, and proposed binding mode of a novel series of pyrrole derivatives as lymphocyte-specific kinase (Lck) inhibitors. The most potent analogs exhibited good enzyme inhibitory activity (IC50s <10 nM) for Lck kinase inhibition. 相似文献
172.
Hiroki Tsumoto Syo Kawahara Yuki Fujisawa Takayoshi Suzuki Hidehiko Nakagawa Kohfuku Kohda Naoki Miyata 《Bioorganic & medicinal chemistry letters》2010,20(6):1948-1952
Water-soluble [60]fullerene (C60) derivatives were synthesized to examine their bioactivities. PC12 cells were used as a model of nerve cells and the bioactivities of synthesized C60 derivatives together with some reported ones were tested. Among the compounds tested, C60/(γ-CyD)2, C60-bis(γ-CyD) (5) containing C60-mono(γ-CyD) (5′), and C60/PVP were sufficiently soluble in water and showed an enhancing effect on the neurite outgrowth of NGF-treated PC12 cells. 相似文献
173.
Yoshiaki Tsuda Haruo Sawada Takafumi Ohsawa Katsuhiro Nakao Hiroki Nishikawa Yuji Ide 《Tree Genetics & Genomes》2010,6(3):377-387
We evaluated the genetic structure of 16 Betula maximowicziana populations in the Chichibu mountain range, central Japan, located within a 25-km radius; all but two populations were at
altitudes of 1,100–1,400 m. The results indicate the effects of geographic topology on the landscape genetic structure of
the populations and should facilitate the development of local-scale strategies to conserve and manage them. Analyses involving
11 nuclear simple sequence repeat loci showed that most populations had similar intrapopulation genetic diversity parameters.
Population differentiation (F
ST = 0.021, G′ST = 0.033) parameters for the populations examined were low but were relatively high compared to those obtained in a previous
study covering populations in a much larger area with a radius of approximately 1,000 km (F
ST = 0.062, G′ST = 0.102). Three populations (Iriyama, Kanayamasawa, and Nishizawa) were differentiated from the other populations by Monmonier’s
and spatial analysis of molecular variance algorithms or by STRUCTURE analysis. Since a high mountain ridge (nearly 2,000 m)
separates the Kanayamasawa and Nishizawa populations from the other 14 populations and the Kanayamasawa and Nishizawa populations
are themselves separated by another mountain ridge, the genetic structure appears to be partly due to mountain ridges acting
as genetic barriers and restricting gene flow. However, the Iriyama population is genetically different but not separated
by any clear geographic barrier. These results show that the landscape genetic structure is complex in the mountain range
and we need to pay attention, within landscape genetic studies and conservation programs, to geographic barriers and local
population differentiation. 相似文献
174.
Maruyama M Yoshitake H Tsukamoto H Takamori K Araki Y 《Biochemical and biophysical research communications》2010,397(1):75-81
Claudin 1 is one of the tight junctional proteins involved in the tight sealing of the cellular sheets and plays a crucial role in the maintenance of cell polarity. Although its structure and physiological function in intercellular adhesion is relatively well understood, we have little information about its possible involvement in early development of vertebrates. We found Xclaudin 1 is expressed maternally in the oocyte of Xenopus laevis and the zygotic expression initiates stage 9 in the animal hemisphere but not in the vegetal hemisphere, limited on the ectoderm and mesoderm until the end of gastrulation. We have investigated a potential role for claudin 1 at gastrulation by gain and loss-of-function studies. Over-expression of Xclaudin 1 resulted in gastrulation defect in a dose-dependent manner. Knockdown of Xclaudin 1 by antisense morpholino oligonucleotides (MOs) blocked convergent extension, whereas ectopic expression of Xclaudin 1-myc mRNA rescued these defects. However, altered expression of Xclaudin 1 did not inhibit mesodermal gene expression. Taken together, our results suggest that Xclaudin 1 is required for proper convergent extension movement during Xenopus gastrulation. 相似文献
175.
Hirotaka Matsukusa Hiroki Oota Kuniaki Haneji Takashi Toma Shoji Kawamura Hajime Ishida 《American journal of physical anthropology》2010,142(2):211-223
The Sakishima islands are members of the Ryukyu island chain, stretching from the southwestern tip of the Japanese archipelago to Taiwan in the East China Sea. Archaeological data indicate cultural similarities between inhabitants of prehistoric Sakishima and Neolithic Taiwan. Recent studies based on tooth crown traits show remarkably high inter‐island diversity among Ryukyu islanders, suggesting that the Sakishima islanders might have genetic backgrounds distinct from main‐island Okinawa people. To investigate the genetic diversity of the Ryukyu islanders, we analyzed mtDNA, Y chromosome, and autosomal short tandem repeat loci in a sample of main‐island Okinawa people and Sakishima (Miyako and Ishigaki) islanders whose participated in a previous study of tooth crown morphology. Our phylogenetic analysis of maternal (mtDNA) and paternal (Y chromosome) lineages shows that the Sakishima islanders are more closely related to people from the Japanese archipelago than to Taiwan aborigines. Miyako islanders and the Hokkaido Ainu have the first and second highest frequencies (respectively) of the Y‐chromosomal Alu‐insertion polymorphism, which is a presumable Jomon marker. Genetic diversity statistics show no evidence of demographic reduction or of extreme isolation in each island's population. Thus, we conclude that 1) Neolithic expansion from Taiwan did not contribute to the gene pool of modern Sakishima islanders, 2) male‐lineage of the Ryukyu islanders likely shares a common ancestor with the Hokkaido Ainu who are presumably direct descendants of the Jomon people, and 3) frequent reciprocal gene flow among islands has masked the trace of common ancestry in the Ryukyu island chain. Am J Phys Anthropol, 2010. © 2010 Wiley‐Liss, Inc. 相似文献
176.
177.
Hiroki Obata Noritaka Kawashima Masami Akai Kimitaka Nakazawa Tatsuyuki Ohtsuki 《Journal of electromyography and kinesiology》2010,20(1):55-60
The purpose of this study was to characterize the effects of aging on the stretch reflex in the ankle muscles, and in particular to compare the effects on the ankle dorsi-flexor (tibialis anterior: TA) and the plantar-flexor (soleus: SOL). Stretch reflex responses were elicited in the TA and SOL at rest and during weak voluntary contractions in 20 elderly and 23 young volunteers. The results indicated that, in the TA muscle, the elderly group had a remarkably larger long-latency reflex (LLR), whereas no aging effect was found in the short latency reflex (SLR). These results were very different from those in the SOL muscle, which showed significant aging effects in the SLR and medium latency reflex (MLR), but not in the LLR. Given the fact that the LLR of the TA stretch reflex includes the cortical pathway, it is probable that the effects of aging on the TA stretch reflex involve alterations not only at the spinal level but also at the cortical level. The present results indicate that the stretch reflexes of each of the ankle antagonistic muscles are affected differently by aging, which might have relevance to the neural properties of each muscle. 相似文献
178.
Sato Takahide; Kusaba Sakiku; Nakagawa Hiroki; Ogura Nagao 《Plant & cell physiology》1985,26(1):211-214
In ripe tomato fruits, polygalacturonase (PG) mRNA comprisedabout 1% of the translatable RNAs in the poly(A)(+)RNA fraction.Sucrose density gradient centrifugation showed that this PGmRNA is similar in size to 18S rRNA, which suggests the presenceof a non-coding region. (Received June 19, 1984; Accepted October 23, 1984) 相似文献
179.
Kubo M Kobayashi K Masegi T Sakai H Tsubota T Asano M Itani M Yanai T 《Journal of wildlife diseases》2007,43(3):542-544
A free-flying Great Egret (Ardea alba) captured in Gifu, central Japan, in May 2006 had a large mass on the right carpal joint. The tumor was diagnosed as chondrosarcoma by histopathologic examination. 相似文献
180.
Biotransformation of raspberry ketone and zingerone by cultured cells of Phytolacca americana 总被引:1,自引:0,他引:1
The biotransformation of raspberry ketone and zingerone were individually investigated using cultured cells of Phytolacca americana. In addition to (2S)-4-(4-hydroxyphenyl)-2-butanol (2%), (2S)-4-(3,4-dihydroxyphenyl)-2-butanol (5%), 4-[4-(beta-d-glucopyranosyloxy)phenyl]-2-butanone (19%), 4-[(3S)-3-hydroxybutyl]phenyl-beta-d-glucopyranoside (23%), and (2S)-4-(4-hydroxyphenyl)but-2-yl-beta-d-glucopyranoside (20%), two biotransformation products, i.e., 2-hydroxy-4-[(3S)-3-hydroxybutyl]phenyl-beta-d-glucopyranoside (12%) and 2-hydroxy-5-[(3S)-3-hydroxybutyl]phenyl-beta-d-glucopyranoside (11%), were isolated from suspension cells after incubation with raspberry ketone for three days. On the other hand, two compounds, i.e., (2S)-4-(4-hydroxy-3-methoxyphenyl)but-2-yl-beta-d-glucopyranoside (17%) and (2S)-2-(beta-d-glucopyranosyloxy)-4-[4-(beta-d-glucopyranosyloxy)-3-methoxyphenyl]butane (16%), together with (2S)-4-(4-hydroxy-3-methoxyphenyl)-2-butanol (15%), 4-[4-(beta-d-glucopyranosyloxy)-3-methoxyphenyl]-2-butanone (21%), and 4-[(3S)-3-hydroxybutyl]-2-methoxyphenyl-beta-d-glucopyranoside (24%) were obtained upon addition of zingerone. Cultured cells of P. americana can reduce, and regioselectively hydroxylate and glucosylate, these food ingredients to their beta-glycosides. 相似文献