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531.
Kazuhiro Nakayama Tumenbayer Bayasgalan Fumiko Tazoe Yoshiko Yanagisawa Takaya Gotoh Kazuhiro Yamanaka Ayumi Ogawa Lkhagvasuren Munkhtulga Ulziiburen Chimedregze Yasuo Kagawa Shun Ishibashi Sadahiko Iwamoto 《Human genetics》2010,127(6):685-690
Recent genome-wide association studies (GWASs) showed that single nucleotide polymorphisms (SNPs) in FADS1/FADS2 were associated with plasma lipid concentrations in populations with European ancestry. We investigated the associations between the SNPs in FADS1/FADS2 and plasma concentrations of triglycerides, high-density lipoprotein cholesterol (HDL-C), and low-density lipoprotein cholesterol (LDL-C) in two Asian groups, i.e., Japanese and Mongolians. The genotype of rs174547 (T/C), found to be associated with triglyceride and HDL-C concentrations in the GWAS, was determined in 21,004 Japanese and 1,203 Mongolian individuals. Genotype–phenotype association was assessed by using multiple linear regression models, assuming an additive model of inheritance. The copy number of the rs174547 C allele was significantly associated with increased triglyceride levels (P = 1.5 × 10?6) and decreased HDL-C levels (P = 0.03) in the Japanese population. On the other hand, in the Mongolian population, the rs174547 C allele copy number was strongly associated with decreased LDL-C levels (P = 2.6 × 10?6), but was not associated with triglyceride and HDL-C levels. The linkage disequilibrium pattern and haplotype structures of SNPs around the FADS1/FADS2 locus showed no marked dissimilarity between Japanese and Mongolian individuals. The present data indicate that the FADS1/FADS2 locus can be added to the growing list of loci involved in polygenic dyslipidemia in Asians. Furthermore, the variable effects of FADS1/FADS2 on plasma lipid profiles in Asians may result from differences in the dietary intake of polyunsaturated fatty acids, which serve as substrates for enzymes encoded by FADS1/FADS2. 相似文献
532.
533.
Junichi Imanishi Aki Nakayama Yoko Suzuki Ayumi Imanishi Nobuyuki Ueda Yukihiro Morimoto Minoru Yoneda 《Landscape and Ecological Engineering》2010,6(2):219-234
Leaf chlorophyll quantification is a key technique in tree vigor assessment. Although many studies have been conducted on
nondestructive and in-field spectroscopic determination, it is reasonable to develop species-specific chlorophyll indices
for accurate determination, because leaf spectra can vary independently of chlorophyll content due to leaf surface and structural
differences among species. The present study aimed to develop optimal reflectance and absorptance indices for estimating the
leaf chlorophyll content of Cerasus jamasakura (Siebold ex Koidz.) H. Ohba var. jamasakura and Cerasus × yedoensis ‘Somei-yoshino,’ and to examine their performance by comparing them with 46 published chlorophyll indices and SPAD. For 96
and 100 leaf samples, measurements were taken using a spectroradiometer with a leaf-clip attachment and a SPAD-502 chlorophyll
meter, and chlorophyll content was determined by extraction with N,N′-dimethylformamide. The optimal leaf chlorophyll indices were then developed systematically by testing eight types of indices.
As a result, we confirmed that the optimal chlorophyll indices performed better than any of the published leaf chlorophyll
indices or SPAD, giving RMSEs that were approximately twice as good as those for SPAD, and found that the newly proposed index
type—a difference and ratio combination type—may be a useful form of chlorophyll content estimation. We also found that absorptance
indices achieved equivalent results to reflectance indices despite the hypothesis that absorptance measurement is direct and
has more potential. Among the published indices, the reflectance ratio index of Datt [Datt B (1999) Int J Remote Sens 20(14):2741–2759] and the red edge chlorophyll index of Ciganda et al. [Ciganda V, Gitelson A, Schepers
J (2009) J Plant Physiol 166:157–167] were effective at estimating the leaf chlorophyll contents of both flowering cherries. 相似文献
534.
Integrating ecological and cultural values toward conservation and utilization of shrine/temple forests as urban green space in Japanese cities 总被引:1,自引:0,他引:1
Hiroaki T. Ishii Tohru Manabe Keitaro Ito Naoko Fujita Ayumi Imanishi Daisuke Hashimoto Ayako Iwasaki 《Landscape and Ecological Engineering》2010,6(2):307-315
In Japan, forests associated with shrines and temples are recognized as important components of urban green space, which can
potentially function as centers for ecosystem conservation in rapidly urbanizing Japanese cities. In addition to their ecological
value, shrine/temple forests have social value, providing recreational and aesthetic needs to residents of urban areas. We
review the historical development of shrine/temple forests in Japan and discuss current conservation issues from both ecological
and sociological perspectives. Generally, shrine forests are minimally managed and public access is discouraged, whereas temple
forests are intensively managed for public display. Shrines tend to be spatially scattered across the landscape but associated
with specific geographical features, whereas temples tend to be clustered. Their wide and random distribution in urban areas
suggests that shrine forests can potentially be used as stepping stones in the urban green space network, whereas spatially
clustered temple forests can be integrated to form large areas of green space. Species diversity of shrine/temple forests
declines with decreasing area. The distribution pattern of species is not completely nested, indicating that although conservation
of large forest fragments may be effective for maintaining landscape-level biodiversity, smaller forest fragments and adjacent
precincts are sometimes significant because rare species occasionally inhabit them. Active management and ecological restoration,
such as removal of invasive species, are also important to maintain the desirable near-natural forest conditions. A working
group including the owner, community, regional government, and ecologists should be involved in creating an effective, long-term
management plan. Because social and cultural values are diverse, basic ecological studies of shrine/temple forests would contribute
a scientific basis that fosters public confidence in the process. 相似文献
535.
Shimamura T Koike-Takeshita A Yokoyama K Masui R Murai N Yoshida M Taguchi H Iwata S 《Structure (London, England : 1993)》2004,12(8):1471-1480
The chaperonins GroEL and GroES are essential mediators of protein folding. GroEL binds nonnative protein, ATP, and GroES, generating a ternary complex in which protein folding occurs within the cavity capped by GroES (cis-cavity). We determined the crystal structure of the native GroEL-GroES-ADP homolog from Thermus thermophilus, with substrate proteins in the cis-cavity, at 2.8 A resolution. Twenty-four in vivo substrate proteins within the cis-cavity were identified from the crystals. The structure around the cis-cavity, which encapsulates substrate proteins, shows significant differences from that observed for the substrate-free Escherichia coli GroEL-GroES complex. The apical domain around the cis-cavity of the Thermus GroEL-GroES complex exhibits a large deviation from the 7-fold symmetry. As a result, the GroEL-GroES interface differs considerably from the previously reported E. coli GroEL-GroES complex, including a previously unknown contact between GroEL and GroES. 相似文献
536.
Yodoya E Wada M Shimada A Katsukawa H Okada N Yamamoto A Ganapathy V Fujita T 《Journal of neurochemistry》2006,97(1):162-173
Na+-coupled carboxylate transporters (NaCs) mediate the uptake of tricarboxylic acid cycle intermediates in mammalian tissues. Of these transporters, NaC3 (formerly known as Na+-coupled dicarboxylate transporter 3, NaDC3/SDCT2) and NaC2 (formerly known as Na+-coupled citrate transporter, NaCT) have been shown to be expressed in brain. There is, however, little information available on the precise distribution and function of both transporters in the CNS. In the present study, we investigated the functional characteristics of Na+-dependent succinate and citrate transport in primary cultures of astrocytes and neurons from rat cerebral cortex. Uptake of succinate was Na+ dependent, Li+ sensitive and saturable with a Michaelis constant (Kt) value of 28.4 microM in rat astrocytes. Na+ activation kinetics revealed that the Na+ to succinate stoichiometry was 3:1 and the concentration of Na+ necessary for half-maximal transport was 53 mM. Although uptake of citrate in astrocytes was also Na+ dependent and saturable, its Kt value was significantly higher (approximately 1.2 mM) than that of succinate. Unlabeled succinate (2 mM) inhibited Na+-dependent [14C]succinate (18 microM) and [14C]citrate (4.5 microM) transport completely, whereas unlabeled citrate inhibited Na+-dependent [14C]succinate uptake more weakly. Interestingly, N-acetyl-L-aspartate, which is the second most abundant amino acid in the nervous system, also completely inhibited Na+-dependent succinate transport in rat astrocytes. The inhibition constant (Ki) for the inhibition of [14C]succinate uptake by unlabeled succinate, N-acetyl-L-aspartate and citrate was 15.9, 155 and 764 microM respectively. In primary cultures of neurons, uptake of citrate was also Na+ dependent and saturable with a Kt value of 16.2 microM, which was different from that observed in astrocytes, suggesting that different Na+-dependent citrate transport systems are expressed in neurons and astrocytes. RT-PCR and immunocytochemistry revealed that NaC3 and NaC2 are expressed in cerebrocortical astrocytes and neurons respectively. These results are in good agreement with our previous reports on the brain distribution pattern of NaC2 and NaC3 mRNA using in situ hybridization. This is the first report of the differential expression of different NaCs in astrocytes and neurons. These transporters might play important roles in the trafficking of tricarboxylic acid cycle intermediates and related metabolites between glia and neurons. 相似文献
537.
Takahashi H Watanabe A Tanaka A Hashida SN Kawai-Yamada M Sonoike K Uchimiya H 《Plant & cell physiology》2006,47(12):1678-1682
Photosynthetic parameters of the nadk2 mutant of Arabidopsis thaliana, which is defective in chloroplast NAD kinase, were investigated. In this plant, the effective efficiency of photosynthetic electron transport (PhiII) and the quantum yield of open reaction centers of photosystem II (Fv'/Fm') were decreased. Furthermore, an increase in non-photochemical quenching attributed to energy dissipation from the xanthophyll cycle was observed. The mutant showed an aberrant de-epoxidation state of xanthophyll cycle carotenoids and had a high level of zeaxanthin even under low light conditions. These results indicate that chloroplast NAD kinase, catalyzing phosphorylation of NAD, is essential for the proper photosynthetic machinery of PSII and the xanthophyll cycle. 相似文献
538.
Hayakawa K Meng Y Hiramatsu N Kasai A Yamauchi K Yao J Kitamura M 《Journal of immunology (Baltimore, Md. : 1950)》2006,176(4):2529-2537
Macrophage-mesangial cell interaction plays a crucial role in the pathogenesis of glomerulonephritis. Activated macrophages trigger mesangial cells to express an array of inflammation-associated genes via activation of NF-kappaB and AP-1. However, this inflammatory response is often transient and subsides spontaneously. We found that mesangial cells activated by bystander macrophages showed blunted responses of NF-kappaB to subsequent macrophage exposure. It was associated with sustained levels of IkappaBbeta, but not IkappaBalpha. The tolerance observed was reversible and reproduced by conditioned media from activated macrophages (macrophage-conditioned medium (MphiCM)). In vivo priming of mesangial cells by activated glomerular macrophages also caused the tolerance of mesangial cells. The macrophage-derived tolerance inducers were heat-labile, and multiple molecules were involved. Among inflammatory cytokines produced by macrophages, TNF-alpha and IL-1beta were able to induce mesangial cell tolerance dose-dependently. The mesangial cell tolerance was also observed in activation of the MAPK-AP-1 pathway; i.e., phosphorylation of ERK, JNK, and p38 MAPK by macrophages was blunted when the cells were pre-exposed to MphiCM. Induction of c-fos and c-jun was also abrogated in mesangial cells pre-exposed to MphiCM, and the suppression was attenuated by blockade of MAPK activation during the first exposure to MphiCM. These data elucidated that mesangial cells, once exposed to macrophages, become insensitive to subsequent activation by macrophages and proinflammatory stimuli. This self defense of glomerular cells may play a role in the resolution of macrophage-mediated, acute glomerulonephritis. 相似文献
539.
Tsuyoshi Hamada Satoshi Murasawa Ayumi Yokoyama Saeko Hayashi Yasushi Kobayashi Takayuki Asahara 《Biochemical and biophysical research communications》2009,381(2):135-138
In the process of hematopoietic stem cell (CD133+ cell) differentiation, a drastic change in gene expression occurs which must be regulated by epigenetic mechanisms. One strategy for CD133+ cell differentiation analysis is to identify genomic DNA regions that have been modified in the process of differentiation. However, it is difficult to obtain large amounts of genomic DNA from uniform CD133+ cells. Based on this situation, we screened genomic DNA regions where modifications change during the process of differentiation in human CD133+ cells using differential methylation site scanning (DMSS), which is a method of identifying differentially methylated regions of the genome from a small number of cells. As a result, we cloned three DNA fragments which corresponded to centrosomal protein 68 kDA (Cep68), TRIO and F-actin binding protein (TRIOBP), and AMP-activated protein kinase beta (AMPKb). 相似文献
540.