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991.
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993.
Andrew R. Greenhill Hirokazu Tsuji Kiyohito Ogata Kazumi Natsuhara Ayako Morita Kevin Soli Jo-Ann Larkins Kiyoshi Tadokoro Shingo Odani Jun Baba Yuichi Naito Eriko Tomitsuka Koji Nomoto Peter M. Siba Paul F. Horwood Masahiro Umezaki 《PloS one》2015,10(2)
There has been considerable interest in composition of gut microbiota in recent years, leading to a better understanding of the role the gut microbiota plays in health and disease. Most studies have been limited in their geographical and socioeconomic diversity to high-income settings, and have been conducted using small sample sizes. To date, few analyses have been conducted in low-income settings, where a better understanding of the gut microbiome could lead to the greatest return in terms of health benefits. Here, we have used quantitative real-time polymerase chain reaction targeting dominant and sub-dominant groups of microorganisms associated with human gut microbiome in 115 people living a subsistence lifestyle in rural areas of Papua New Guinea. Quantification of Clostridium coccoides group, C. leptum subgroup, C. perfringens, Bacteroides fragilis group, Bifidobacterium, Atopobium cluster, Prevotella, Enterobacteriaceae, Enterococcus, Staphylococcus, and Lactobacillus spp. was conducted. Principle coordinates analysis (PCoA) revealed two dimensions with Prevotella, clostridia, Atopobium, Enterobacteriaceae, Enterococcus and Staphylococcus grouping in one dimension, while B. fragilis, Bifidobacterium and Lactobacillus grouping in the second dimension. Highland people had higher numbers of most groups of bacteria detected, and this is likely a key factor for the differences revealed by PCoA between highland and lowland study participants. Age and sex were not major determinants in microbial population composition. The study demonstrates a gut microbial composition with some similarities to those observed in other low-income settings where traditional diets are consumed, which have previously been suggested to favor energy extraction from a carbohydrate rich diet. 相似文献
994.
In the presence of a redox mediator, 1-hydroxybenzotriazole (HBT), iso-butylparaben (iso-BP) and n-butylparaben (n-BP) were treated with laccase from white rot fungus Trametes versicolor. HPLC analysis demonstrated that iso-BP and n-BP almost completely disappeared from the reaction mixture after 4 h of treatment with the laccase-HBT system. Using the
yeast two-hybrid assay system, it was also confirmed that the laccase-HBT system substantially removed the estrogenic activity
of iso-BP and n-BP after 4 h of treatment. Furthermore, there was a linear relationship between the removal of estrogenic activity of both
parabens and the decrease in their concentrations. These results demonstrate that the laccase-HBT system is effective in eliminating
iso-BP and n-BP, and removing the estrogenic activity of both parabens. 相似文献
995.
Wada Kojiro; Marumo Shingo; Ikekawa Nobuo; Morisaki Masuo; Mori Kenji 《Plant & cell physiology》1981,22(2):323-325
Brassinolide, a new plant growth-promoting steroid lactone,and its synthetic analog, homobrassinolide, showed strong activityin stimulating the lamina inclination of rice plants at verylow concentrations of 0.0005 and 0.005 µg/ml, respectively,whereas IAA showed only a weak effect on the lamina inclinationat 50 µg/ml. Thus, the lamina inclination test is usefulas a highly sensitive bioassay for brassinolide and relatedcompounds. (Received November 26, 1980; Accepted December 22, 1980) 相似文献
996.
997.
Shingo Kato Clara Chan Takashi Itoh Moriya Ohkuma 《Applied and environmental microbiology》2013,79(17):5283-5290
Iron-rich flocs often occur where anoxic water containing ferrous iron encounters oxygenated environments. Culture-independent molecular analyses have revealed the presence of 16S rRNA gene sequences related to diverse bacteria, including autotrophic iron oxidizers and methanotrophs in iron-rich flocs; however, the metabolic functions of the microbial communities remain poorly characterized, particularly regarding carbon cycling. In the present study, we cultivated iron-oxidizing bacteria (FeOB) and performed clone library analyses of functional genes related to carbon fixation and methane oxidization (cbbM and pmoA, respectively), in addition to bacterial and archaeal 16S rRNA genes, in freshwater iron-rich flocs at groundwater discharge points. The analyses of 16S rRNA, cbbM, and pmoA genes strongly suggested the coexistence of autotrophic iron oxidizers and methanotrophs in the flocs. Furthermore, a novel stalk-forming microaerophilic FeOB, strain OYT1, was isolated and characterized phylogenetically and physiologically. The 16S rRNA and cbbM gene sequences of OYT1 are related to those of other microaerophilic FeOB in the family Gallionellaceae, of the Betaproteobacteria, isolated from freshwater environments at circumneutral pH. The physiological characteristics of OYT1 will help elucidate the ecophysiology of microaerophilic FeOB. Overall, this study demonstrates functional roles of microorganisms in iron flocs, suggesting several possible linkages between Fe and C cycling. 相似文献
998.
Yasuko Kato Naoko Kaneko Masato Sawada Keishi Ito Sousuke Arakawa Shingo Murakami Kazunobu Sawamoto 《PloS one》2012,7(11)
Sensory input is essential for the normal development of sensory centers in the brain, such as the somatosensory, visual, auditory, and olfactory systems. Visual deprivation during a specific developmental stage, called the critical period, results in severe and irreversible functional impairments in the primary visual cortex. Olfactory deprivation in the early postnatal period also causes significant developmental defects in the olfactory bulb, the primary center for olfaction. Olfactory bulb interneurons are continuously generated from neural stem cells in the ventricular-subventricular zone, suggesting that the olfactory system has plasticity even in adulthood. Here, we investigated the effect of transient neonatal olfactory deprivation on the addition of interneurons to the glomerular layer of the adult mouse olfactory bulb. We found that the addition of one subtype of interneurons was persistently inhibited even after reopening the naris. BrdU pulse-chase experiments revealed that the neonatal olfactory deprivation predominantly affected an early phase in the maturation of this neuronal subtype in the olfactory bulb. Subjecting the mice to odor stimulation for 6 weeks after naris reopening resulted in significant recovery from the histological and functional defects caused by the olfactory deprivation. These results suggest that a subtype-specific critical period exists for olfactory bulb neurogenesis, but that this period is less strict and more plastic compared with the critical periods for other systems. This study provides new insights into the mechanisms of postnatal neurogenesis and a biological basis for the therapeutic effect of olfactory training. 相似文献
999.
1000.
Kikushige Y Shima T Takayanagi S Urata S Miyamoto T Iwasaki H Takenaka K Teshima T Tanaka T Inagaki Y Akashi K 《Cell Stem Cell》2010,7(6):708-717
Acute myeloid leukemia (AML) originates from self-renewing leukemic stem cells (LSCs), an ultimate therapeutic target for AML. Here we identified T cell immunoglobulin mucin-3 (TIM-3) as a surface molecule expressed on LSCs in most types of AML except for acute promyelocytic leukemia, but not on normal hematopoietic stem cells (HSCs). TIM-3(+) but not TIM-3? AML cells reconstituted human AML in immunodeficient mice, suggesting that the TIM-3(+) population contains most, if not all, of functional LSCs. We established an anti-human TIM-3 mouse IgG2a antibody having complement-dependent and antibody-dependent cellular cytotoxic activities. This antibody did not harm reconstitution of normal human HSCs, but blocked engraftment of AML after xenotransplantation. Furthermore, when it is administered into mice grafted with human AML, this treatment dramatically diminished their leukemic burden and eliminated LSCs capable of reconstituting human AML in secondary recipients. These data suggest that TIM-3 is one of the promising targets to eradicate AML LSCs. 相似文献