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81.
Pregestational weight status and maternal smoking during pregnancy are significantly associated with fetal and childhood growth. However, few studies have examined associations between childhood growth and combinations of these factors using multilevel analysis. This study aimed to describe differences in childhood growth trajectories according to these combinations, using data from a prospective cohort study in Japan. The study participants were 1,973 women and their singletons, who were born between April 1, 1991 and March 31, 2003. Children were categorized according to whether they were born to normal-weight, nonsmoking mothers (NN); normal-weight, smoking mothers (NS); underweight, nonsmoking mothers (UN); underweight, smoking mothers (US); overweight, nonsmoking mothers (ON); or overweight, smoking mothers (OS). Birth weight and anthropometric data were collected from 1,965 children at birth (99.6%), 1,655 aged 3 (83.9%), 1,527 aged 5 (77.4%), 1,497 aged 7–8 (75.9%), and 1,501 aged 9–10 (76.1%). Multilevel analysis examining both individual and age as different level variables according to sex was used to describe the trajectories of body mass index z scores for statistical analyses. Although children of the OS group were the leanest at birth, their body mass indices had increased rapidly by 3 years of age. Moreover, body mass index was also likely to increase in boys in the NS and ON groups. A different trend was observed in girls. Body mass index decreased from 5 years of age in girls in the US group. There were no remarkable differences in body mass index trajectories between children in the other groups. In conclusion, childhood growth trajectories differed according to combinations of pregestational weight status and maternal smoking during pregnancy. Further, there were sex-related differences in the associations between childhood growth and factor combinations.  相似文献   
82.
One of the most common types of urinary stones formed in humans and some other mammals is composed of calcium oxalate in ordered hydrated crystals. Many studies have reported a range of metals other than calcium in human stones, but few have looked at stones from animal models such as the dog. Therefore, we determined the elemental profile of canine calcium oxalate urinary stones and compared it to reported values from human stones. The content of 19 elements spanning 7-orders of magnitude was quantified in calcium oxalate stones from 53 dogs. The elemental profile of the canine stones was highly overlapping with human stones, indicating similar inorganic composition. Correlation and cluster analysis was then performed on the elemental profile from canine stones to evaluate associations between the elements and test for potential subgrouping based on elemental content. No correlations were observed with the most abundant metal calcium. However, magnesium and sulfur content correlated with the mineral hydration form, while phosphorous and zinc content correlated with the neuter status of the dog. Inter-elemental correlation analysis indicated strong associations between barium, phosphorous, and zinc content. Additionally, cluster analysis revealed subgroups within the stones that were also based primarily on barium, phosphorous, and zinc. These data support the use of the dog as a model to study the effects of trace metal homeostasis in urinary stone disease.  相似文献   
83.
The photoreceptors for chloroplast photorelocation movement have been known, but the signal(s) raised by photoreceptors remains unknown. To know the properties of the signal(s) for chloroplast accumulation movement, we examined the speed of signal transferred from light-irradiated area to chloroplasts in gametophytes of Adiantum capillus-veneris. When dark-adapted gametophyte cells were irradiated with a microbeam of various light intensities of red or blue light for 1 min or continuously, the chloroplasts started to move towards the irradiated area. The speed of signal transfer was calculated from the relationship between the timing of start moving and the distance of chloroplasts from the microbeam and was found to be constant at any light conditions. In prothallial cells, the speed was about 1.0 µm min−1 and in protonemal cells about 0.7 µm min−1 towards base and about 2.3 µm min−1 towards the apex. We confirmed the speed of signal transfer in Arabidopsis thaliana mesophyll cells under continuous irradiation of blue light, as was about 0.8 µm min−1. Possible candidates of the signal are discussed depending on the speed of signal transfer.Key words: Adiantum capillus-veneris, Arabidopsis thaliana, blue light, chloroplast movement, microbeam, red light, signalOrganelle movement is essential for plant growth and development and tightly regulated by environmental conditions.1 It is well known that light regulates chloroplast movement in various plant species. Chloroplast movement can be separated into three categories, (1) photoperception by photoreceptors, (2) signal transduction from photoreceptor to chloroplasts and (3) movement of chloroplasts and has been analyzed from a physiological point of view.2 We recently identified the photoreceptors in Arabidopsis thaliana, fern Adiantum capillus-veneris, and moss Physcomitrella patens. In A. thaliana, phototropin 2 (phot2) mediates the avoidance movement,3,4 whereas both phototropin 1 (phot1) and phot2 mediate the accumulation response.5 A chimeric photoreceptor neochrome 1 (neo1)6 was identified as a red/far-red and blue light receptor that mediates red as well as blue light-induced chloroplast movement in A. capillusveneris.7 Interestingly, neo1 mediated red and blue light-induced nuclear movement and negative phototropic response of A. capillus-veneris rhizoid cells.8,9 On the mechanism of chloroplast movement, we also found a novel structure of actin filaments that appeared between chloroplast and the plasma membrane at the front side of moving chloroplast.10 Recent studies using the technique of microbeam irradiation have revealed that chloroplasts do not have a polarity for light-induced accumulation movement and can move freely in any direction both in A. capillus-veneris prothallial cells and in A. thaliana mesophyll cells.11 However, the signal that may be released from photoreceptors and transferred to chloroplasts remains unknown.To understand the properties of the signal for the chloroplast accumulation response, we examined the speed of signal transfer in dark-adapted A. capillus-veneris gametophyte cells and A. thaliana mesophyll cells by partial cell irradiation with a red and/or blue microbeam of various light intensities for 1 min and the following continuous irradiation, respectively.12As shown in Figure 1, the relation between the distance of chloroplasts from the microbeam and the timing when each chloroplast started moving toward the microbeam irradiated area (shown as black dots in Fig. 1) was obtained and plotted. The lag time between the onset of microbeam irradiation and the timing of start moving of chloroplasts is the time period needed for a signal to reach each chloroplast. To obtain more accurate data many chloroplasts at various positions were used. The slope of the approximate line indicates the average speed of the signal transfer. Shown with a protonemal cell at the left side of this figure is an instance where the speed of signal transfer from basal-to-apical (acropetal) direction is obtained.Open in a separate windowFigure 1How to calculate the speed of signal transfer in the basal cell of two-celled protonema of Adiantum capillus-veneris. The relationship between the distance of chloroplast position from the edge of the microbeam to the center of each chloroplast as shown in left side of figure and the timing of chloroplast movement initiated shown as the black dots was obtained. Inclination of the approximate lines connecting dots indicates the speeds of the signal transfer.In protonemal cells, which are tip-growing linear cells, the average speed of signal transfer was about 2.3 µm min−1 from basal-to-apical (acropetal) and about 0.7 µm min−1 from apical-to-basal (basipetal) directions. These values were almost constant irrespective of light intensity, wavelength, irradiation period, and the region of the cell irradiated.12 The difference of speed between basipetal and acropetal directions may be depending on cell polarity. The signal transfer in prothallial cells of A. capillus-veneris and mesophyll cells of A. thaliana was about 1.0 µm min−1 to any direction, probably because they may not have a polarity comparing to protonemal cells or have a weak polarity if any. Thus, the speed of signal transfer must be conserved in most land plants,12 if not influenced by strong polarity.
R1W m−2R1W m−2B1W m−2R0.1W m−2R10W m−2B10W m−2
1 mincountinuouscountinuouscountinuouscountinuouscountinuous
Protonemal cell (towards apical region)2.322.372.282.412.39
Protonemal cell (towards basal region)0.580.730.800.740.86
Prothallial cell1.130.921.101.080.95
Arabidopsis thaliana0.70
Open in a separate windowThe speeds of signal transfer under different light intensities and wave length in Adiantum capillus-veneris gametophyte cells and Arabidopsis thaliana mesophyll cells are summarized. When dark-adapted cells were irradiated with various light intensities (red light: 10, 1, 0.1 W m−2) of a microbeam of red or blue light for 1 min or continuously, the chloroplasts moved towards the irradiated area. The speed of signal transfer was measured from the relationship between the timing of onset of moving and the distance of chloroplalsts from the microbeam irradiated area.Calcium ions have been proposed as one of the candidates of the signal. Calcium is reported to be necessary for chloroplast movement in some plants.13,14 Chloroplast movement under polarized light could not be induced in the existence of EGTA in protonemal cells of A. capillus-veneris, although chloroplasts show slight movement in random direction.13 In Lemna trisulca, chloroplast movement correlates with an increase of cytoplasmic calcium levels and is inhibited by antagonists of calcium homeostasis.14 The speed of intracellular transfer of calcium ions in plant cells was measured only in moss Physcomitrella patens by microinjection of a calcium indicator into protonemal cells.15 The speed of calcium waves in the cytoplasm of protonemal cell was about 3.4 µm sec−1. The speed of substance transfer as signals is not known in plant cells except for the above instance, as far as we know, but in animal cells various experimental data has been accumulated.1621The transfer speed of calcium waves visualizing cytoplasmic free calcium by microinjection of aequorin was about 8 µm sec−1 in Xenopus eggs.16 Calcium ion expands as a spherical wave and the wave speed in plane is 50 µm sec−1 in rat cardiac myocytes when measured by loading a membrane-permeable indicator of calcium into the cell. The maximum velocity was 112 µm sec−1.17 Calcium waves could also be observed in the SR-free single isolated rabbit cardiac myofibrils with a propagation velocity of 15.5 µm sec−1.18 The propagation velocity of the calcium wave was about 65–100 µm sec−1 by calciuminduced calcium release (CICR) in pig heart muscle cells.1921 Comparing these values to our data in A. capillus-veneris, the speed of signal transfer in chloroplast movement in fern gametophytes was 100–200 times slower than those measured for calcium ion transfers in animal cells, suggesting that the calcium might not be the signal involved in chloroplast movement.Intracellular transport is depended on the cytoskeleton systems in many cases. So the speed of movement of the cytoskeleton itself has been examined. When motor-proteins (such as 22s dynein, 14s dynein, kinesin) were anchored on a slide glass microtubules overlaid moved with a speed of about 4.52, 4.29, 0.422 µm sec−1, respectively. In similar ways, actin filaments placed over myosin-coated glass moved at about 5.21 µm sec-1.22 On the other hand, the motor domain of the Centromere Binding Factor (CBF) protein complex moves at 4.04 µm min−1 on microtubules.23 In A. capillus-veneris protonemal cells, the speed of cytoplasmic streaming depending on the actomyosin system was calculated from the speed of oil drop movement.24 The speed was dependent upon the position of long protonemal cells and was about 2 µm min−1 in the apical region and gradually increased to 10 µm min−1 in the basal region. In comparison to the data cited here, the speed of signal transfer involved in chloroplast accumulation was 30–120 times slower than the speed of the actomyosin system or the microtubule-kinesin/dynein system, but it is similar to the moving speed of a protein complex on a microtubule23 and oil droplets in a protonemal cell.24Polymerization rates of cytoskeletal proteins have been measured using in vitro systems. For instance, the plus end of microtubules from bovine brains grew at 1.04–1.88 µm min−1.25,26 Polymerization rate of actin filaments from rabbit muscle was about 0.13–0.49 µm min−1 and depended on the G-actin concentration.27 Live BHK21 fibroblasts, mouse melanoma cells and Dictyostelium amoebae expressing GFP-actin fusion proteins move on glass by using three-dimensional F-actin bands. These structures propagate throughout the cytoplasm at rates ranging between 2–5 µm min−1 in each cell type and produce lamellipodia or pseudopodia at the cell boundary.28 The extending speed of these cytoskeletons is roughly equal to the speed of signal transfer for the chloroplast accumulation response. We therefore aim to measure the speed of extension of these filaments when a method of gene transformation has been established for A. capillus-veneris.  相似文献   
84.
Sexual process in eight-spored ascus-forming yeast, Schizosaccharomyces japonicus II. Dependency of the sexual process on the carbon source     
Ohashi  Kunihiro; Tsuboi  Michio; Hayashibe  Masaya 《Plant & cell physiology》1979,20(1):157-164
The carbon-source dependency of the sexual process in Schizosaccharomycesjaponicus was studied. Schiz. japonicus grew well in vegetativemedia containing glucose, sucrose, fructose or raffinose, anddid poorly in one containing mannose. On the other hand, itssexual process proceeded well in sporulation media containingglucose, sucrose or mannose, and was markedly delayed in thosecontaining fructose or raffinose. Neither vegetative growthnor sexual process occurred when non-fermentable carbon sources,such as glycerol, were used. The amount of glucose in the sporulationmedium sufficient for completion of the sexual process varieddepending on the cell-population density. Glucose was requiredfor both zygote and ascus formation but not for spore liberation.Cells were committed to sporulation shortly after the stageof zygote formation. (Received August 3, 1978; )  相似文献   
85.
Succination of protein thiols during adipocyte maturation: a biomarker of mitochondrial stress     
Nagai R  Brock JW  Blatnik M  Baatz JE  Bethard J  Walla MD  Thorpe SR  Baynes JW  Frizzell N 《The Journal of biological chemistry》2007,282(47):34219-34228
Although obesity is a risk factor for development of type 2 diabetes and chemical modification of proteins by advanced glycoxidation and lipoxidation end products is implicated in the development of diabetic complications, little is known about the chemical modification of proteins in adipocytes or adipose tissue. In this study we show that S-(2-succinyl)cysteine (2SC), the product of chemical modification of proteins by the Krebs cycle intermediate, fumarate, is significantly increased during maturation of 3T3-L1 fibroblasts to adipocytes. Fumarate concentration increased > or =5-fold during adipogenesis in medium containing 30 mm glucose, producing a > or =10-fold increase in 2SC-proteins in adipocytes compared with undifferentiated fibroblasts grown in the same high glucose medium. The elevated glucose concentration in the medium during adipocyte maturation correlated with the increase in 2SC, whereas the concentration of the advanced glycoxidation and lipoxidation end products, N(epsilon)-(carboxymethyl)lysine and N(epsilon)-(carboxyethyl)lysine, was unchanged under these conditions. Adipocyte proteins were separated by one- and two-dimensional electrophoresis and approximately 60 2SC-proteins were detected using an anti-2SC polyclonal antibody. Several of the prominent and well resolved proteins were identified by matrix-assisted laser desorption ionization time-of-flight/time-of-flight mass spectrometry. These include cytoskeletal proteins, enzymes, heat shock and chaperone proteins, regulatory proteins, and a fatty acid-binding protein. We propose that the increase in fumarate and 2SC is the result of mitochondrial stress in the adipocyte during adipogenesis and that 2SC may be a useful biomarker of mitochondrial stress in obesity, insulin resistance, and diabetes.  相似文献   
86.
Role of distal upstream sequence in vitamin D-induced expression of human CYP24 gene     
Tashiro K  Ishii C  Ryoji M 《Biochemical and biophysical research communications》2007,358(1):259-265
The level of CYP24 mRNA in cultured human fibroblasts increases up to 20,000-fold in response to 1,25-dihydroxyvitamin D(3). Two vitamin D-responsive elements (VDREs) located immediately upstream of the CYP24 gene are primarily responsible for the induction. We studied roles of other regions in the 5'-flanking sequence of this gene. A series of deletion constructs between nucleotides -1918 and +209 of the gene were examined for their promoter activities employing the luciferase reporter assay. We found that the VDREs were not sufficient to account for the extent of induction. The sequence between nucleotides -548 and -294, which is located immediately upstream of the VDREs and includes three potential Sp1 sites, acted synergistically with the VDREs for the induction. Further upstream sequence and the 5'-untranslated region did not appear to play a major role in the vitamin D response.  相似文献   
87.
NELF interacts with CBC and participates in 3' end processing of replication-dependent histone mRNAs     
Narita T  Yung TM  Yamamoto J  Tsuboi Y  Tanabe H  Tanaka K  Yamaguchi Y  Handa H 《Molecular cell》2007,26(3):349-365
  相似文献   
88.
Sex Attraction and Mating in Bursaphelenchus okinawaensis and B. xylophilus     
Ryoji Shinya  Anthony Chen  Paul W. Sternberg 《Journal of nematology》2015,47(3):176-183
The fungal feeding, hermaphroditic Bursaphelenchus okinawaensis is a laboratory model to understand the biology of Bursaphelenchus. The extent to which B. okinawaensis can be used to model Bursaphelenchus xylophilus mating was investigated. A chemotaxis assay was conducted to examine whether B. xylophilus and B. okinawaensis produce and respond to volatile sex attractants. Unmated B. xylophilus females were found to attract B. xylophilus males. Similarly, old (sperm depleted) but not young (sperm repleted) B. okinawaensis hermaphrodites attract B. okinawaensis males. Thus, in both species, sperm status corresponds to its ability to attract males. B. xylophilus males also produce a volatile pheromone that attracts both mated and unmated females. A second assay, in which the behavior of males on petri plates in the presence of different females or hermaphrodites of Bursaphelenchus was observed, revealed that B. xylophilus unmated females attract B. okinawaensis males, and B. okinawaensis old hermaphrodites attract B. xylophilus males. These observations suggested that the pheromones of Bursaphelenchus work to some extent across species. Mating behavior through spicule insertion occurs across species, suggesting that postcopulatory mechanisms prevent production of interspecific progeny. The hermaphroditic B. okinawaensis will be a useful model to conduct genetic studies for the understanding of the molecular mechanisms underlying mating behavior in Bursaphelenchus nematodes.  相似文献   
89.
PGC-1α-mediated changes in phospholipid profiles of exercise-trained skeletal muscle     
Nanami Senoo  Noriyuki Miyoshi  Naoko Goto-Inoue  Kimiko Minami  Ryoji Yoshimura  Akihito Morita  Naoki Sawada  Junichiro Matsuda  Yoshihiro Ogawa  Mitsutoshi Setou  Yasutomi Kamei  Shinji Miura 《Journal of lipid research》2015,56(12):2286-2296
Exercise training influences phospholipid fatty acid composition in skeletal muscle and these changes are associated with physiological phenotypes; however, the molecular mechanism of this influence on compositional changes is poorly understood. Peroxisome proliferator-activated receptor γ coactivator 1α (PGC-1α), a nuclear receptor coactivator, promotes mitochondrial biogenesis, the fiber-type switch to oxidative fibers, and angiogenesis in skeletal muscle. Because exercise training induces these adaptations, together with increased PGC-1α, PGC-1α may contribute to the exercise-mediated change in phospholipid fatty acid composition. To determine the role of PGC-1α, we performed lipidomic analyses of skeletal muscle from genetically modified mice that overexpress PGC-1α in skeletal muscle or that carry KO alleles of PGC-1α. We found that PGC-1α affected lipid profiles in skeletal muscle and increased several phospholipid species in glycolytic muscle, namely phosphatidylcholine (PC) (18:0/22:6) and phosphatidylethanolamine (PE) (18:0/22:6). We also found that exercise training increased PC (18:0/22:6) and PE (18:0/22:6) in glycolytic muscle and that PGC-1α was required for these alterations. Because phospholipid fatty acid composition influences cell permeability and receptor stability at the cell membrane, these phospholipids may contribute to exercise training-mediated functional changes in the skeletal muscle.  相似文献   
90.
Discovery of selective indole-based prostaglandin D₂ receptor antagonist     
Iwahashi M  Shimabukuro A  Onoda T  Matsunaga Y  Okada Y  Matsumoto R  Nambu F  Nakai H  Toda M 《Bioorganic & medicinal chemistry》2011,19(15):4574-4588
A series of N-benzoyl-2-methylindole-3-acetic acids were synthesized and biologically evaluated as prostaglandin (PG) D? receptor antagonists. Some of the selected compounds significantly inhibited OVA-induced vascular permeability in guinea pig conjunctiva after oral dosing. Structure-activity relationship study is presented.  相似文献   
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