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91.
A genetic analysis of hydrologically dispersed seeds of Hibiscus moscheutos (Malvaceae) 总被引:1,自引:0,他引:1
The dispersal of floating seeds in wetland habitats should influence the genetic characteristics of plant metapopulations. We examined gene flow of a hydrochorous wetland macrophyte, Hibiscus moscheutos L. (Malvaceae), by analyzing allozyme variation in current-year floating-seed populations. The genetic composition of floating seeds was compared to the genetic composition of established populations of H. moscheutos that had been previously analyzed in the same areas. The F statistics demonstrated that genetic structuring among floating-seed populations was weak or absent, indicating that seeds from source populations were thoroughly mixed. Floating-seed populations had an excess of homozygotes, a different situation than had previously been found in established populations. The exchange of seeds was greatest among H. moscheutos populations that were adjacent to a tidal stream. We conclude that populations adjacent to the tidal streams are part of a metapopulation that serves as a reserve of genetic variation in the system. Although established populations of H. moscheutos that are not close to the tidal stream are relatively isolated genetically, we found evidence that they also contribute to the floating-seed populations within the estuary. 相似文献
92.
Noda S Mashima Y Obazawa M Kubota R Oguchi Y Kudoh J Minoshima S Shimizu N 《Biochemical and biophysical research communications》2000,276(3):1129-1135
We investigated the expression of myocilin in the optic nerve head of porcine eyes by Western blotting and immunohistochemical staining. Myocilin was localized in the nucleus, centrosome, glial filament, mitochondria, and some parts of the cell membranes of the astrocytes. Myocilin was also detected at the edge-feet portion of the processes of astrocytes adjacent to the inner limiting membrane and blood vessel wall. The astrocytes are the major cell population in the optic nerve head, contributing to the architecture of the nerve axon and blood vessels. Therefore, myocilin gene mutation and change of myocilin protein are likely to affect the architecture of the optic nerve head and induce various forms of glaucomatous optic nerve damage. 相似文献
93.
Up-regulation of natriuretic peptides in the ventricle of Csx/Nkx2-5 transgenic mice 总被引:3,自引:0,他引:3
Takimoto E Mizuno T Terasaki F Shimoyama M Honda H Shiojima I Hiroi Y Oka T Hayashi D Hirai H Kudoh S Toko H Kawamura K Nagai R Yazaki Y Komuro I 《Biochemical and biophysical research communications》2000,270(3):1074-1079
A cardiac homeobox-containing gene Csx/Nkx2-5, which is essential for cardiac development, is abundantly expressed in the adult heart as well as in the heart primordia. Targeted disruption of this gene results in embryonic lethality due to abnormal heart morphogenesis. To elucidate the role of Csx/Nkx2-5 in the adult heart, we generated transgenic mice which overexpress human Csx/Nkx2-5. The transgene was expressed abundantly in the heart and the skeletal muscle. mRNA levels of several cardiac genes including natriuretic peptides, CARP, MLC2v, and endogenous Csx/Nkx2-5 were increased in the ventricle of the transgenic mice. Electron microscopic analysis revealed that the ventricular myocardium of the transgenic mice had many secretory granules, which disappeared after administration of vasopressin. These results suggest that Csx/Nkx2-5 regulates many cardiac genes and induces formation of secretory granules in the adult ventricle. 相似文献
94.
Ulla Aapola Kazunori Shibuya Hamish S. Scott Juha Ollila Mauno Vihinen Maarit Heino Ai Shintani Kazuhiko Kawasaki Shinsei Minoshima Kai Krohn Stylianos E. Antonarakis Nobuyoshi Shimizu Jun Kudoh Prt Peterson 《Genomics》2000,65(3):293
We have isolated the DNMT3L gene that is related to the cytosine-5-methyltransferase 3 (DNMT3) family. The gene is located on chromosome 21q22.3 between the AIRE and the KIAA0653 genes and spans approximately 16 kb of genomic sequence. The encoded protein of 387 amino acids has a cysteine-rich region containing a novel-type zinc finger domain that is conserved in DNMT3A and DNMT3B but also in ATRX, a member of the SNF2 protein family. The novel domain, called an ADD (ATRX, DNMT3, DNMT3L)-type zinc finger, contains two subparts: a C2C2 and an imperfect PHD zinc finger. Expression of the DNMT3L mRNA was not detectable by Northern blotting; however, RT-PCR amplification revealed that it is expressed at low levels in several tissues including testis, ovary, and thymus. 相似文献
95.
96.
Takashi Kudoh Akira Matsuda Satoshi Shuto Takashi Murayama Yasuo Ogawa 《Nucleosides, nucleotides & nucleic acids》2013,32(4-6):583-599
We previously showed that 3″-deoxy-cyclic ADP-carbocyclic-ribose (3″-deoxy-cADPcR, 3) is a stable and highly potent analogue of cyclic ADP-ribose (cADPR, 1), a Ca2+-mobilizing second messenger. From these results, we newly designed another 3″-modified analogues of cADPcR and identified the N1-“xylo”-type carbocyclic analogue, i.e., cADPcX (4), as one of the most potent cADPR-related compounds reported so far. 相似文献
97.
Hiroyuki Taniguchi Yasuhiro Kondoh Masahito Ebina Arata Azuma Takashi Ogura Yoshio Taguchi Moritaka Suga Hiroki Takahashi Koichiro Nakata Atsuhiko Sato Yukihiko Sugiyama Shoji Kudoh Toshihiro Nukiwa 《Respiratory research》2011,12(1):1-9
Background
The rate of decline in forced expiratory volume in 1 second (FEV1) is representative of the natural history of COPD. Sparse information exists regarding the associations between the magnitude of annualised loss of FEV1 with other endpoints.Methods
Retrospective analysis of UPLIFT® trial (four-year, randomized, double-blind, placebo-controlled trial of tiotropium 18 μg daily in chronic obstructive pulmonary disease [COPD], n = 5993). Decline of FEV1 was analysed with random co-efficient regression. Patients were categorised according to quartiles based on the rate of decline (RoD) in post-bronchodilator FEV1. The St George's Respiratory Questionnaire (SGRQ) total score, exacerbations and mortality were assessed within each quartile.Results
Mean (standard error [SE]) post-bronchodilator FEV1 increased in the first quartile (Q1) by 37 (1) mL/year. The other quartiles showed annualised declines in FEV1 (mL/year) as follows: Q2 = 24 (1), Q3 = 59 (1) and Q4 = 125 (2). Age, gender, respiratory medication use at baseline and SGRQ did not distinguish groups. The patient subgroup with the largest RoD had less severe lung disease at baseline and contained a higher proportion of current smokers. The percentage of patients with ≥ 1 exacerbation showed a minimal difference from the lowest to the largest RoD, but exacerbation rates increased with increasing RoD. The highest proportion of patients with ≥ 1 hospitalised exacerbation was in Q4 (Q1 = 19.5% [tiotropium], 26% [control]; Q4 = 33.8% [tiotropium] and 33.1% [control]). Time to first exacerbation and hospitalised exacerbation was shorter with increasing RoD. Rate of decline in SGRQ increased in direct proportion to each quartile. The group with the largest RoD had the highest mortality.Conclusion
Patients can be grouped into different RoD quartiles with the observation of different clinical outcomes indicating that specific (or more aggressive) approaches to management may be needed.Trial Registration
ClinicalTrials.gov number, NCT00144339 相似文献98.
Tomohito Matsuo Yukiko Noguchi Mieko Shindo Yoshifumi Morita Yoshie Oda Eiko Yoshida Hiroko Hamada Mine Harada Yuichi Shiokawa Takahiro Nishida Ryuji Tominaga Yoshikane Kikushige Koichi Akashi Jun Kudoh Nobuyoshi Shimizu Yuka Tanaka Tsukuru Umemura Taketoshi Taniguchi Akihiko Yoshimura Takashi Kobayashi Masao Mitsuyama Hironori Kurisaki Hitoshi Katsuta Seiho Nagafuchi 《Gene》2013
Although mutations of autoimmune regulator (AIRE) gene are responsible for autoimmune polyendocrinopathy-candidiasis-ectodermal dystrophy (APECED), presenting a wide spectrum of many characteristic and non-characteristic clinical features, some patients lack AIRE gene mutations. Therefore, something other than a mutation, such as dysregulation of AIRE gene, may be a causal factor for APECED or its related diseases. However, regulatory mechanisms for AIRE gene expression and/or translation have still remained elusive. We found that IL-2-stimulated CD4+ T (IL-2T) cells showed a high expression of AIRE gene, but very low AIRE protein production, while Epstein–Barr virus-transformed B (EBV-B) cells express both AIRE gene and AIRE protein. By using microarray analysis, we could identify miR-220b as a possible regulatory mechanism for AIRE gene translation in IL-2T cells. Here we report that miR-220b significantly reduced the expression of AIRE protein in AIRE gene with 3′UTR region transfected 293T cells, whereas no alteration of AIRE protein production was observed in the open reading frame of AIRE gene alone transfected cells. In addition, anti-miR-220b reversed the inhibitory function of miR-220b for the expression of AIRE protein in AIRE gene with 3′UTR region transfected cells. Moreover, when AIRE gene transfected cells with mutated 3′UTR were transfected with miR-220b, no reduction of AIRE protein production was observed. Taken together, it was concluded that miR-220b inhibited the AIRE gene translation through the 3′UTR region of AIRE gene, indicating that miR-220b could serve as a regulator for human AIRE gene translation. 相似文献
99.
? Premise of the study: Microsatellite markers were developed to analyze the clonal diversity and population genetic structure of a clonal plant, Cardamine leucantha. ? Methods and Results: Microsatellite loci were isolated by using compound simple sequence repeat (SSR) primers, resulting in 25 pairs including 14 useful markers. Samples from 33, 20, and 17 ramets in three populations were identified as belonging to 23, 18, and 17 genotypic individuals, respectively. ? Conclusions: These SSR markers will be used for identifying genets and evaluating genetic diversity of the clonal plant C. leucantha. 相似文献
100.
Effects of light quality on leaf morphogenesis of a heterophyllous amphibious plant, Rotala hippuris 总被引:1,自引:0,他引:1