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11.
Talukder Byomkesh Nobukazu Nakagoshi Ashraf M. Dewan 《Landscape and Ecological Engineering》2012,8(1):45-58
Green space is particularly indispensable for proper functioning of the ecosystem in an urban environment. This study was
an attempt to dynamically map and monitor green spaces in Greater Dhaka of Bangladesh. Both primary and secondary data were
acquired to document the spatial–temporal dynamics of green spaces in the study area. Using a supervised classification algorithm,
multi-temporal land use/cover data were extracted from a set of satellite images. A number of spatial metrics were employed
to understand the landscape condition in a multi-temporal manner. In addition, 50 key informants along with focus group discussion
and observation techniques were used to document existing management aspects of green spaces and their conservation policies.
The analysis revealed that green spaces in Greater Dhaka are rapidly disappearing over the course of time even though they
provide a number of natural, economic and social benefits. The disappearance of green spaces was primarily attributed to a
rapid increase in the urban population, mainly driven by rural–urban migration. As a result, the landscape became highly fragmented
and less connected. A substantial reduction of green patches is also leading to deterioration of the ecological condition
of the landscape. The drastic reduction of green spaces in Greater Dhaka has been attributed to a lack of policy, low political
motivation, and poor management. In order to ensure sustainability of green spaces and proper functioning of the city’s ecosystem,
there is an urgent need for strategic green space planning. 相似文献
12.
Nameki N Yoneyama M Koshiba S Tochio N Inoue M Seki E Matsuda T Tomo Y Harada T Saito K Kobayashi N Yabuki T Aoki M Nunokawa E Matsuda N Sakagami N Terada T Shirouzu M Yoshida M Hirota H Osanai T Tanaka A Arakawa T Carninci P Kawai J Hayashizaki Y Kinoshita K Güntert P Kigawa T Yokoyama S 《Protein science : a publication of the Protein Society》2004,13(8):2089-2100
GCN2 is the alpha-subunit of the only translation initiation factor (eIF2alpha) kinase that appears in all eukaryotes. Its function requires an interaction with GCN1 via the domain at its N-terminus, which is termed the RWD domain after three major RWD-containing proteins: RING finger-containing proteins, WD-repeat-containing proteins, and yeast DEAD (DEXD)-like helicases. In this study, we determined the solution structure of the mouse GCN2 RWD domain using NMR spectroscopy. The structure forms an alpha + beta sandwich fold consisting of two layers: a four-stranded antiparallel beta-sheet, and three side-by-side alpha-helices, with an alphabetabetabetabetaalphaalpha topology. A characteristic YPXXXP motif, which always occurs in RWD domains, forms a stable loop including three consecutive beta-turns that overlap with each other by two residues (triple beta-turn). As putative binding sites with GCN1, a structure-based alignment allowed the identification of several surface residues in alpha-helix 3 that are characteristic of the GCN2 RWD domains. Despite the apparent absence of sequence similarity, the RWD structure significantly resembles that of ubiquitin-conjugating enzymes (E2s), with most of the structural differences in the region connecting beta-strand 4 and alpha-helix 3. The structural architecture, including the triple beta-turn, is fundamentally common among various RWD domains and E2s, but most of the surface residues on the structure vary. Thus, it appears that the RWD domain is a novel structural domain for protein-binding that plays specific roles in individual RWD-containing proteins. 相似文献
13.
Hidehiko Kumagai Nobukazu Kashima Hiroshi Torii Hideaki Yamada Hitoshi Enei Shinji Okumuea 《Bioscience, biotechnology, and biochemistry》2013,77(3):472-482
Crystalline tyrosine phenol lyase was prepared from the cell extract of Erwinia herbicola grown in a medium supplemented with l-tyrosine. The crystalline enzyme was homogeneous by the criteria of ultracentrifugation and acrylamide gel electrophoresis. The molecular weight was determined to be approximately 259,000. The crystalline enzyme catalyzed the conversion of l-tyrosine into phenol, pyruvate and ammonia, in the presence of added pyridoxal phosphate. The enzyme also catalyzed pyruvate formation from d-tyrosine, S-methyl-l-cysteine, 3, 4-dihydroxyphenyl-l-alanine, l- and d-serine, and l- and d-cysteine, but at lower rates than from l-tyrosine. l-Phenyl-alanine, l-alanine, phenol and pyrocatechol inhibited pyruvate formation from l-tyrosine.Crystalline tyrosine phenol lyase from Erwinia herbicola is inactive in the absence of added pyridoxal phosphate. Binding of pyridoxal phosphate to the apoenzyme is accompanied by pronounced increase in absorbance at 340 and 425 mμ. The amount of pyridoxal phosphate bound to the apoenzyme was determined by equilibrium dialysis to be 2 moles per mole of enzyme. Addition of the substrate, l-tyrosine, or the competitive inhibitors, l-alanine and l-phenyl-alanine, to the holoenzyme causes appearance of a new absorption peak near 500 mμ which disappears as the substrate is decomposed but remains unchanged in the presence of the inhibitor. 相似文献
14.
15.
Echinops setifer is an endangered grassland plant species in Japan. We isolated and characterized nine microsatellite loci in this species.
The number of alleles ranged from 3 to 7 and expected heterozygosities from 0.108 to 0.761. These markers described here will
be useful for investigating the genetic diversity, genetic structure and gene flow, and planning for conservation of E. setifer. 相似文献
16.
17.
Takashi Hattori Takashi Mine Nobukazu Komatsu Akira Yamada Kyogo Itoh Hitoshi Shiozaki Kiyotaka Okuno 《Cancer immunology, immunotherapy : CII》2009,58(11):1843-1852
To investigate the safety and immunological responses of personalized peptide vaccination in combination with oral administration
of UFT and UZEL for metastatic colorectal carcinoma (mCRC), fourteen patients were enrolled in the present study. Peptides
were determined based on the presence of peptide-specific cytotoxic T lymphocyte precursors and IgG in each patient. A maximum
of four peptides were subcutaneously administered weekly with UFT (300 mg/m2 day−1) and UZEL (75 mg/day) for 4 weeks, followed by 1 week of rest. This therapy was well-tolerated although there was a grade-3
skin reaction at the vaccination site in one patient. An increase in peptide-specific interferon-γ production or peptide-specific
IgG after the tenth vaccination was observed in nine of ten or eight of ten patients tested, respectively. IgG responses were
well correlated with overall survival (P = 0.0215). The safety and immunological responsiveness of the present therapy suggest that this combination would be of clinical
benefit for mCRC patients, and further trials are merited.
T. Hattori and T. Mine equally contributed to this work. 相似文献
18.
Nameki N Someya T Okano S Suemasa R Kimoto M Hanawa-Suetsugu K Terada T Shirouzu M Hirao I Takaku H Himeno H Muto A Kuramitsu S Yokoyama S Kawai G 《Journal of biochemistry》2005,138(6):729-739
Small protein B, SmpB, is a tmRNA-specific binding protein essential for trans-translation. We examined the interaction between SmpB and tmRNA from Thermus thermophilus, using biochemical and NMR methods. Chemical footprinting analyses using full-length tmRNA demonstrated that the sites protected upon SmpB binding are located exclusively in the tRNA-like domain (TLD) of tmRNA. To clarify the SmpB binding sites, we constructed several segments derived from TLD. Optical biosensor interaction analyses and melting profile analyses with mutational studies showed that SmpB efficiently binds to only a 30-nt segment that forms a stem and loop, with the 5' and 3' extensions composed of the D-loop and variable-loop analogues. The conserved sequences, 16UCGA and 319GAC, in the extensions are responsible for the SmpB binding. These results agree with the those visualized by the cocrystal structure of TLD and SmpB from Aquifex aeolicus. In addition, NMR chemical shift mapping analyses, using the 30-nt segment and (15)N-labeled SmpB, revealed the characteristic RNA binding mode. The hydrogen bond pattern around beta2 changes, with the Gly in beta2, which acts as a hinge, showing the largest chemical shift change. It appears that SmpB undergoes structural changes indicating an induced fit upon binding to the specific region of TLD. 相似文献
19.
Nobukazu Araki Yoichiro Takashima Takashi Makita 《Histochemistry and cell biology》1995,104(4):257-265
The redistribution and fate of colchicine-induced alkaline phosphatase (ALPase) in rat hepatocytes were investigated by electron microscopic enzyme cytochemistry and biochemistry. ALPase activity markedly increased in rat hepatocytes after colchicine treatment (2.0 mg/kg body weight, intraperitoneal injection). At 20–24 h after colchicine treatment, the liver showed the highest activity of ALPase. Thereafter, ALPase activity decreased and returned to normal levels at 48 h. In normal hepatocytes from control rats, ALPase activity was seen only on the bile canalicular membrane. However, at 20–24 h after colchicine treatment, colchicine-induced ALPase was redistributed in the sinusoidal and lateral (basolateral) membranes as well as in the bile canalicular membrane. At 30–36 h after colchicine treatment, ALPase activity on the basolateral membrane gradually decreased. In contrast, ALPase in the bile canalicular membrane increased along with the enlargement of bile canaliculi, suggesting that ALPase in the basolateral membrane had been transported to the bile canalicular membrane. Furthermore, ALPase-positive vesicles, cisternae and autophagosome-like structures were frequently seen in the cytoplasm. ALPase was also positive in some lysosomal membranes. ALPase in hepatocytes at 48 h after colchicine treatment returned to almost the same location as in control hepatocytes. Altogether, it is suggested that excessively induced ALPase is at least partially retrieved by invagination of the bile canalicular membrane and then transported to lysosomes for degradation. In addition, this study indicates that excess plasma membrane might be a possible origin of autophagosomal membrane. 相似文献
20.
Masanori Noguchi Tatsuyuki Kakuma Hirotsugu Uemura Yasutomo Nasu Hiromi Kumon Yasuhiko Hirao Fukuko Moriya Shigetaka Suekane Kei Matsuoka Nobukazu Komatsu Shigeki Shichijo Akira Yamada Kyogo Itoh 《Cancer immunology, immunotherapy : CII》2010,59(7):1001-1009
Personalized peptide vaccination (PPV) combined with chemotherapy could be a novel approach for many cancer patients. In this randomized study, we evaluated the anti-tumor effect and safety of PPV plus low-dose estramustine phosphate (EMP) as compared to standard-dose EMP for HLA-A2- or -A24-positive patients with castration resistant prostate cancer. Patients were randomized into groups receiving either PPV plus low-dose EMP (280 mg/day) or standard-dose EMP (560 mg/day). After disease progression, patients were switched to the opposite regime. The primary end point was progression-free survival (PFS). We randomly assigned 28 patients to receive PPV plus low-dose EMP and 29 patients to receive standard-dose EMP. Nineteen events in the PPV group and 20 events in the EMP group occurred during the first treatment. Median PFS for the first treatment was 8.5 months in the PPV group and 2.8 months in the EMP group with a hazard ratio (HR) of 0.28 (95% CI, 0.14–0.61; log-rank P = 0.0012), while there was no difference for median PFS for the second treatment. The HR for overall survival was 0.3 (95% CI, 0.1–0.91) in favor of the PPV plus low-dose EMP group (log-rank, P = 0.0328). The PPV plus low-dose EMP was well tolerated without major adverse effects and with increased levels of IgG and cytotoxic-T cell responses to the vaccinated peptides. PPV plus low-dose EMP was associated with an improvement in PSA-based PFS as compared to the standard-dose EMP alone. 相似文献