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31.
Yosuke Demizu Nanako Yamagata Yukiko Sato Mitsunobu Doi Masakazu Tanaka Haruhiro Okuda Masaaki Kurihara 《Journal of peptide science》2010,16(3):153-158
One chiral L ‐valine (L ‐Val) was inserted into the C‐terminal position of achiral peptide segments constructed from α‐aminoisobutyric acid (Aib) and α,β‐dehydrophenylalanine (ΔZPhe) residues. The IR, 1H NMR and CD spectra indicated that the dominant conformations of the pentapeptide Boc‐Aib‐ΔPhe‐(Aib)2‐L ‐Val‐NH‐Bn (3) and the hexapeptide Boc‐Aib‐ΔPhe‐(Aib)3‐L ‐Val‐NH‐Bn (4) in solution were both right‐handed (P) 310‐helical structures. X‐ray crystallographic analyses of 3 and 4 revealed that only a right‐handed (P) 310‐helical structure was present in their crystalline states. The conformation of 4 was also studied by molecular‐mechanics calculations. Copyright © 2010 European Peptide Society and John Wiley & Sons, Ltd. 相似文献
32.
Yosuke Demizu Masakazu Tanaka Mitsunobu Doi Masaaki Kurihara Haruhiro Okuda Hiroshi Suemune 《Journal of peptide science》2010,16(11):621-626
A single chiral cyclic α,α‐disubstituted amino acid, (3S,4S)‐1‐amino‐(3,4‐dimethoxy)cyclopentanecarboxylic acid [(S,S)‐Ac5cdOM], was placed at the N‐terminal or C‐terminal positions of achiral α‐aminoisobutyric acid (Aib) peptide segments. The IR and 1H NMR spectra indicated that the dominant conformations of two peptides Cbz‐[(S,S)‐Ac5cdOM]‐(Aib)4‐OEt ( 1) and Cbz‐(Aib)4‐[(S,S)‐Ac5cdOM]‐OMe (2) in solution were helical structures. X‐ray crystallographic analysis of 1 and 2 revealed that a left‐handed (M) 310‐helical structure was present in 1 and that a right‐handed (P) 310‐helical structure was present in 2 in their crystalline states. Copyright © 2010 European Peptide Society and John Wiley & Sons, Ltd. 相似文献
33.
The aim of this study was to develop in situ gellable hydrogels composed of periodate oxidized citrus pectin (OP) for localized anticancer drug delivery and evaluate the potential of OP to inhibit cancer metastasis. Doxorubicin (Dox) was coupled to OP by imine bonds. Adipic dihydrazide (ADH) was used for cross-linking of the Dox-OP conjugates. The Dox-OP conjugate solution gelled within 2 min after addition of ADH. The release rate of Dox from the hydrogels was controllable by an additive amount of ADH. The released Dox retained anticancer activity. OP was shown to have a potency to prevent homotypic cancer cell aggregation compared to unmodified citrus pectin, strongly suggesting that OP released from hydrogels in vivo will inhibit cancer metastasis. These results indicate that OP hydrogels have the potential to prevent progression of primary cancer by the released Dox and generation of metastatic cancer by the released OP. 相似文献
34.
Takako Shima-Sano Rika Yamada Kazuyo Sekita Raleigh W. Hankins Hiromasa Hori Hiroshi Seto Koji Sudo Makiko Kondo Kazuo Kawahara Yuki Tsukahara Noriyuki Inaba Shingo Kato Mitsunobu Imai 《PloS one》2010,5(2)
Background
Prenatal human immunodeficiency virus (HIV) testing is essential for the prevention of mother-to-child transmission. However, false-positive results of screening testing are a concern as they may cause unnecessary emotional stress to pregnant women waiting for confirmatory test results. In regions with an extremely low prevalence, the positive predictive values of screening are unacceptably low rate. Here, we propose a HIV screening algorithm consisting of serial two fourth-generation enzyme immunoassays to reduce the number of false-positive screening results.Methodology/Principal Findings
When 6461 pregnant women presenting to two maternity hospitals located in the Tokyo metropolitan area of Japan from September, 2004 to January, 2006 were tested using Enzygnost HIV Integral as a first screening test, 27 showed positive reactions. When these positive reaction samples were tested using VIDAS HIV DUO Quick as a second screening test, only one of them had a positive reaction, and the remaining 26 were nonreactive. Confirmatory Western blots and nucleic acid amplification test also showed that one was positive and the remaining 26 were negative; the subject who was positive with the confirmatory tests was identical to the subject who was positive with the second screening test. Thus, by adding the second screening test, the false-positive rate was improved from 0.4% to 0%, and the positive predictive value from 3.7% to 100%, compared with the single screening test.Conclusion
By applying our serial screening algorithm to HIV testing in maternity hospitals, many uninfected pregnant women would not need to receive confirmatory tests and be subjected to emotional turmoil while waiting for their confirmatory test results. This algorithm would be suitable for HIV testing of pregnant women living in low prevalence regions such as Japan. 相似文献35.
A new assay for the analysis of X-chromosome inactivation based on methylation-specific PCR 总被引:3,自引:0,他引:3
Kubota T Nonoyama S Tonoki H Masuno M Imaizumi K Kojima M Wakui K Shimadzu M Fukushima Y 《Human genetics》1999,104(1):49-55
The pattern of X-chromosome inactivation in females is currently evaluated by assays of differential methylation in the genes
between the active and the inactive X chromosomes, with methylation-sensitive enzymes. We report a new assay in the human
androgen receptor (HUMARA) locus involving a methylation-specific polymerase chain reaction (M-PCR) technique, independent of the use of restriction
enzymes. The assay involves the chemical modification of DNA with sodium bisulfite and subsequent PCR. By using the assay
with specific primers for the methylated allele, we obtained an X-inactivation pattern based on the ratio of the maternal
inactive X to the paternal inactive X. These patterns were consistent with those obtained by conventional PCR assay at the
same locus in 48 female cases. We also obtained another X-inactivation pattern based on the ratio of the maternal active X
to the paternal active X by using specific primers for the unmethylated allele. The latter pattern was complementary to the
former pattern, and a combination of these patterns produced a reliable X-inactivation pattern. The assay revealed that 12
(11%) of the 105 normal females had non-random inactivation patterns (>80:20 or <20:80). Four patients with an X; autosome
translocation showed extremely non-random patterns, and these results were consistent with those obtained by previous molecular/cytogenetic
studies. We conclude that M-PCR provides an accurate assay for X-inactivation and that it can be performed on various DNA
samples unsuitable for restriction digestion.
Received: 3 September 1998 / Accepted: 10 October 1998 相似文献
36.
37.
Prenatal diagnosis of ornithine transcarbamylase deficiency by using a single nucleated erythrocyte from maternal blood 总被引:7,自引:0,他引:7
A. Watanabe Akihiko Sekizawa Atsushi Taguchi Hiroshi Saito Takumi Yanaihara Mitsunobu Shimazu Ichiro Matsuda 《Human genetics》1998,102(6):611-615
We have developed a method that allows the prenatal DNA diagnosis of ornithine transcarbamylase (OTC) deficiency by using
a single fetal nucleated erythrocyte (NRBC) isolated from maternal blood. OTC gene analysis of a male patient (TF) with early
onset OTC deficiency was performed by single-strand conformation polymorphism (PCR-SSCP) and DNA sequencing. To investigate
the possible prenatal diagnosis of OTC deficiency, maternal blood was obtained at 13 weeks of gestation of a subsequent pregnancy,
from the mother of patient TF. NRBCs in the maternal blood were separated by using the density gradient method and then collected
with a micromanipulator. The entire genome of a single NRBC was amplified by primer extension preamplification (PEP). The
human leukocyte antigen (HLA)-DQ alpha genotype and sex were determined from small aliquots of the PEP product. The HLA-DQ
alpha genotype of each of the parents of the male patient was also determined. Once a single NRBC had been identified as being
of fetal origin, the OTC gene was analyzed by using the restriction fragment length polymorphism (RFLP) method. DNA analysis
revealed a point mutation in exon 9 of the OTC gene in the OTC-deficient patient (TF). All NRBCs retrieved from maternal blood
were successfully identified as being of fetal origin by HLA-DQ alpha genotyping and sex determination. RFLP analysis demonstrated
that the fetal OTC gene was normal. This is the first study to successfully diagnose OTC deficiency prenatally, by using a
single fetal NRBC from the maternal circulation. Such prenatal DNA diagnosis is non-invasive and can be applied to other genetic
diseases, including autosomal and X-linked diseases.
Received: 19 December 1997 / Accepted: 14 February 1998 相似文献
38.
Tomomi Yano Mitsunobu Kamiya Akio Murakami Hideaki Sasaki Hiroshi Kawai 《Journal of phycology》2006,42(1):155-169
Among five species of the genus Plocamium Lamouroux distributed around Japan, P. cartilagineum (Linnaeus) Dixon, P. recurvatum Okamura and P. telfairiae (Hooker and Harvey) Harvey are often difficult to distinguish morphologically from each other. Our previous study demonstrated that P. recurvatum and P. telfairiae were divided into two groups, A and C, based on RUBISCO spacer sequence and that the specimens belonging to group C had acidic cell saps. In this study, we inferred evolutionary relationships of these Plocamium species from internal transcribed spacer sequence of the ribosomal RNA genes and obtained a similar topology to the RUBISCO spacer tree. Color of the dried specimens in the acidic group C was darker red than that in the non‐acidic group A, although there was no difference in color in living thalli. The Br? concentration in the cell sap of the acidic group C was 20 times higher than that of the non‐acidic group. We could not find any morphological differences to distinguish clearly between groups A and C despite exhaustive investigation of field‐collected and cultured thalli in both P. recurvatum and P. telfairiae. These results suggest that the color of dried specimens and the composition of intracellular inorganic ions are significant criteria for interpreting phylogenetic relationships in Japanese Plocamium spp. 相似文献
39.
Yamanaka A Imai H Adachi M Komatsu M Islam AT Kodama I Kitazawa C Endo K 《Zoological science》2004,21(10):1049-1055
Diapause pupae of Papilio xuthus show color polymorphism, represented by diapause-green, orange, and brownish-orange types that are each associated with specific pupation sites. We investigated the role of the site of pupation on the induction of the development of orange types (or brownish-orange types), and the endocrine mechanism underlying the control of color polymorphism in short-day pupae. All short-day larvae of the wandering stage developed into orange or brownish-orange type pupae when they were placed in rough-surfaced containers after gut-purge. Utilizing a pharate pupal ligation between the thorax and abdomen, the endocrine mechanism underlying the control of color polymorphism was shown to involve a head-thorax factor (Orange-Pupa-Inducing Factor: OPIF) that induced orange types in short-day pupae. OPIF was bioassayed using the ligated abdomens of short-day pharate pupae. OPIF was extractable with 2% NaCl solution from 5th-instar larval ganglia complexes following the mesothoracic complex (TG(2,3)-AG(1-7)), but it could not be extracted with either acetone or 80% ethanol solution. OPIF may not exist in the brains of day-0 pupae or in brain-subesophageal ganglion and prothoracic ganglion complexes of 5th-instar larvae. The short-day pharate pupae responded to OPIF in a dose-dependent manner. 相似文献
40.
Small GTPase proteins Rin and Rit Bind to PAR6 GTP-dependently and regulate cell transformation 总被引:1,自引:0,他引:1
The novel small GTPases Rin and Rit are close relatives of Ras, and recent studies show that they play a role in mediating neuronal differentiation. However, the direct effectors of Rin and Rit have yet to be fully characterized. Here we showed that Rin and Rit directly bind to the PDZ domain of PAR6, a cell polarity-regulating protein, in a GTP-dependent manner both in vivo and in vitro. Moreover, Rin and Rit can form a ternary complex consisting of PAR6 and Rac/Cdc42, members of the Rho family of small GTPases modulating cell growth and polarity. This ternary complex synergistically potentiates cell transformation in NIH3T3 cells, and the interaction between Rin/Rit and the PDZ domain of PAR6 is important for this effect. These results suggest that the Rin/Rit-PAR6-Rac/Cdc42 ternary complex may work physiologically in the cells, such as in tumorigenesis. 相似文献