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21.
Yasuyuki Taira Naomi Hayashida Rimi Tsuchiya Hitoshi Yamaguchi Jumpei Takahashi Alexander Kazlovsky Marat Urazalin Tolebay Rakhypbekov Shunichi Yamashita Noboru Takamura 《PloS one》2013,8(2)
For the current on-site evaluation of the environmental contamination and contributory external exposure after the accident at the Chernobyl Nuclear Power Plant (CNPP) and the nuclear tests at the Semipalatinsk Nuclear Testing Site (SNTS), the concentrations of artificial radionuclides in soil samples from each area were analyzed by gamma spectrometry. Four artificial radionuclides (241Am, 134Cs, 137Cs, and 60Co) were detected in surface soil around CNPP, whereas seven artificial radionuclides (241Am, 57Co, 137Cs, 95Zr, 95Nb, 58Co, and 60Co) were detected in surface soil around SNTS. Effective doses around CNPP were over the public dose limit of 1 mSv/y (International Commission on Radiological Protection, 1991). These levels in a contaminated area 12 km from Unit 4 were high, whereas levels in a decontaminated area 12 km from Unit 4 and another contaminated area 15 km from Unit 4 were comparatively low. On the other hand, the effective doses around SNTS were below the public dose limit. These findings suggest that the environmental contamination and effective doses on the ground definitely decrease with decontamination such as removing surface soil, although the effective doses of the sampling points around CNPP in the present study were all over the public dose limit. Thus, the remediation of soil as a countermeasure could be an extremely effective method not only for areas around CNPP and SNTS but also for areas around the Fukushima Dai-ichi Nuclear Power Plant (FNPP), and external exposure levels will be certainly reduced. Long-term follow-up of environmental monitoring around CNPP, SNTS, and FNPP, as well as evaluation of the health effects in the population residing around these areas, could contribute to radiation safety and reduce unnecessary exposure to the public. 相似文献
22.
Masao Iwamori Yuriko Iwamori Shigeki Adachi Taisei Nomura 《Glycoconjugate journal》2013,30(9):889-897
The major lipid constituent of symbiotic gram-positive bacteria in animals are phosphatidylglycerol, cardiolipin and dihexaosyl diglycerides (DH-DG), whose hydrophobic structures are characteristic of the environments, and the carbohydrate structures of DH-DGs are bacterial species-characteristic. Immunization of rabbits with intestinal lactobacilli generated antibodies against DH-DGs and their modified structures, among which Galα1-6-substituted DH-DG, i.e., Lactobacillus tetrahexaosyl diglyceride (LacTetH-DG), reacted with antibodies more intensely than DH-DG. Whereas, from the 16S-rRNA sequence, the intestinal lactobacilli in murine digestive tracts were revealed to be L. johnsonii, in which LacTetH-DG is present at the concentration of 2.2 ng per 1?×?106 cells. To obtain more accurate estimates of intestinal lactobacilli in several regions of the digestive tract of mice, LacTetH-DG was detected by TLC-immunostaining with anti-Lactobacillus antisera, being found in the stomach, cecum and colon of normal breeding mice, 1.0?×?109, 3.5?×?109 and 7.4?×?109 cells, respectively. Administration of penicillin and streptomycin for 6 days resulted in a reduction in the number of intestinal lactobacilli, the levels being 0 %, 30 % and 4 % of the control ones in the stomach, cecum and colon, respectively, which was associated with the accumulation of the contents in the tracts from the stomach to the cecum and with diarrhea. In addition, a reduced amount of fucosyl GA1 (FGA1) and a compensatory increase in GA1 due to the reduced activity of α1,2-fucosyltransferase in the small intestine and the enhanced discharge of FGA1 into the contents occurred in mice, probably due to the altered population of bacteria caused by administration of penicillin and streptomycin. 相似文献
23.
Israt Jahan Yuriko Hirai Zahed Mohammad Malequr Rahman Md Anwarul Islam Hirohisa Hirai 《Primates; journal of primatology》2013,54(4):335-340
Hoolock gibbons (genus Hoolock) are a group of very endangered primate species that belong to the small ape family (family Hylobatidae). The entire population that is distributed in the northeast and southeast of Bangladesh is estimated to include only around 350 individuals. A conservation program is thus necessary as soon as possible. Genetic markers are significant tools for planning such programs. In this study, we examined chromosomal characteristics of two western hoolock gibbons that were captured in a Bangladesh forest. During chromosome analysis, we encountered two chromosome variations that were observed for the first time in the wild-born western hoolock gibbons (Hoolock hoolock). The first one was a nonhomologous centromere position in chromosome 8 that was observed in the two examined individuals. The alteration was identical in the two individuals, which were examined by G-band and DAPI-band analyses. Chromosome paint analyses revealed that the difference in the centromere position was due to a single small pericentric inversion. The second variation was a heterozygous elongation in chromosome 9. Analysis by sequential techniques of fluorescence in situ hybridization with 18S rDNA and silver nitrate staining revealed a single and an inverted tandem duplication, respectively, of the nucleolus organizer region in two individuals. These chromosome variations provide useful information for the next steps to consider the evolution and conservation of the hoolock gibbon. 相似文献
24.
Yuriko Furuya Atsushi Inagaki Masud Khan Kaoru Mori Josef M. Penninger Midori Nakamura Nobuyuki Udagawa Kazuhiro Aoki Keiichi Ohya Kohji Uchida Hisataka Yasuda 《The Journal of biological chemistry》2013,288(8):5562-5571
To date, parathyroid hormone is the only clinically available bone anabolic drug. The major difficulty in the development of such drugs is the lack of clarification of the mechanisms regulating osteoblast differentiation and bone formation. Here, we report a peptide (W9) known to abrogate osteoclast differentiation in vivo via blocking receptor activator of nuclear factor-κB ligand (RANKL)-RANK signaling that we surprisingly found exhibits a bone anabolic effect in vivo. Subcutaneous administration of W9 three times/day for 5 days significantly augmented bone mineral density in mouse cortical bone. Histomorphometric analysis showed a decrease in osteoclastogenesis in the distal femoral metaphysis and a significant increase in bone formation in the femoral diaphysis. Our findings suggest that W9 exerts bone anabolic activity. To clarify the mechanisms involved in this activity, we investigated the effects of W9 on osteoblast differentiation/mineralization in MC3T3-E1 (E1) cells. W9 markedly increased alkaline phosphatase (a marker enzyme of osteoblasts) activity and mineralization as shown by alizarin red staining. Gene expression of several osteogenesis-related factors was increased in W9-treated E1 cells. Addition of W9 activated p38 MAPK and Smad1/5/8 in E1 cells, and W9 showed osteogenesis stimulatory activity synergistically with BMP-2 in vitro and ectopic bone formation. Knockdown of RANKL expression in E1 cells reduced the effect of W9. Furthermore, W9 showed a weak effect on RANKL-deficient osteoblasts in alkaline phosphatase assay. Taken together, our findings suggest that this peptide may be useful for the treatment of bone diseases, and W9 achieves its bone anabolic activity through RANKL on osteoblasts accompanied by production of several autocrine factors. 相似文献
25.
Takeshi Hashimoto Takumi Yokokawa Yuriko Endo Nobumasa Iwanaka Kazuhiko Higashida Sadayoshi Taguchi 《Biochemical and biophysical research communications》2013
Background
A previous study has demonstrated that endurance training under hypoxia results in a greater reduction in body fat mass compared to exercise under normoxia. However, the cellular and molecular mechanisms that underlie this hypoxia-mediated reduction in fat mass remain uncertain. Here, we examine the effects of modest hypoxia on adipocyte function.Methods
Differentiated 3T3-L1 adipocytes were incubated at 5% O2 for 1 week (long-term hypoxia, HL) or one day (short-term hypoxia, HS) and compared with a normoxia control (NC).Results
HL, but not HS, resulted in a significant reduction in lipid droplet size and triglyceride content (by 50%) compared to NC (p < 0.01). As estimated by glycerol release, isoproterenol-induced lipolysis was significantly lowered by hypoxia, whereas the release of free fatty acids under the basal condition was prominently enhanced with HL compared to NC or HS (p < 0.01). Lipolysis-associated proteins, such as perilipin 1 and hormone-sensitive lipase, were unchanged, whereas adipose triglyceride lipase and its activator protein CGI-58 were decreased with HL in comparison to NC. Interestingly, such lipogenic proteins as fatty acid synthase, lipin-1, and peroxisome proliferator-activated receptor gamma were decreased. Furthermore, the uptake of glucose, the major precursor of 3-glycerol phosphate for triglyceride synthesis, was significantly reduced in HL compared to NC or HS (p < 0.01).Conclusion
We conclude that hypoxia has a direct impact on reducing the triglyceride content and lipid droplet size via decreased glucose uptake and lipogenic protein expression and increased basal lipolysis. Such an hypoxia-induced decrease in lipogenesis may be an attractive therapeutic target against lipid-associated metabolic diseases. 相似文献26.
Masataka Ishinaga Hitoshi Takamura Hiroshi Narita Makoto Kito 《Bioscience, biotechnology, and biochemistry》2013,77(9):2741-2746
When rats were fed on a diet containing sardine oil (SO) for 10 days, 20:5 (eicosapentaenoic acid) was incorporated into the platelet, aorta and plasma lipids. The 20:5/20:4 (arachidonic acid) ratios of phospholipids were higher in platelets than in aortas. When the diet was changed from SO to corn oil (CO), the levels of 20:5 in the plasma lipids and platelet phospholipids decreased with an increase of 20:4. Although the 20:5 levels of phospholipids in the aortas decreased, 20:4 did not increase during feeding with the CO diet for 4 days. The 20:5/20:4 ratios of the phosphatidylcholine in platelets and aortas rapidly changed from 5.0 and 1.1 to 2.4 and 0.6, respectively. The linoleic acid level of phosphatidylcholine in platelets and aortas increased rapidly by changing from the SO diet to the CO diet, but this fatty acid was not incorporated into phosphatidylinositol of the platelets and aortas. 相似文献
27.
Yoshichika Takamura Tomiko Takamura Masami Soejima Teijiro Uemura 《Bioscience, biotechnology, and biochemistry》2013,77(5):718-728
Maleate cis-trans isomerase in Alcaligenes faecalis IB–14 was induced by malonate and purified about 100-fold over the crude cell-free extract by treatments of ammonium sulfate fractionation, Sephadex G–100 gel filtration, DEAE-cellulose and DEAE-Sephadex A–50 column chromatography. The preparation was shown to be monodisperse on ultracentrifugal analysis and Svedberg value was found to be 3.84 S.The enzyme was most active at pH value around 8.3 and was stable over the range of pH 5.0 to 7.0 in the presence of dithiothreitol (DTT) for a few weeks, but in the absence of it, the enzyme activity was markedly decreased, especially in the alkaline region. The enzyme activity was inhibited by various sulfhydryl reagents and oxidizing agents, whereas it was not affected by metal chelating agents. The inhibition by Hg2+ and PCMB was overcome by the addition of sulfhydryl compounds such as DTT, 2-mercaptoethanol, l-cysteine and glutathione. It was observed that the enzyme did not require co-factor for its function.Kinetic studies showed that Michaelis constant for maleate was 2.8×10?3 m and the enzyme did not catalyze the reverse reaction. 相似文献
28.
Yuji Shimizu Mio Nakazato Takaharu Sekita Koichiro Kadota Kazuhiko Arima Hironori Yamasaki Hisashi Goto Satoshi Shirahama Noboru Takamura Kiyoshi Aoyagi Takahiro Maeda 《Journal of physiological anthropology》2013,32(1):19
Background
Previous studies have reported an inverse association between height and risk of cardiovascular disease. However, evidence is limited for the association between risk of atherosclerosis and height. Further, although the association between atherosclerosis and body mass index (BMI) is reportedly positive, there have been no reports of studies on associations between height and atherosclerosis in relation to BMI.Methods
We conducted a cross-sectional study of Japanese men aged 30 to 89 years undergoing general health check-ups.Results
Of the 1,337 men, 312 were diagnosed with carotid atherosclerosis (carotid intima-media thickness (CIMT) ≥ 1.1 mm), but no significant association was found between height and carotid atherosclerosis for the entire study group. Stratification by BMI status of those analytical findings disclosed a significant inverse association between height and carotid atherosclerosis among overweight (BMI ≥ 25 kg/m2) but not among non-overweight (BMI < 25 kg/m2) men. The classical cardiovascular risk factors-adjusted odds ratio (OR) and 95% confidence interval (CI) of carotid atherosclerosis for an increment of one SD (standard deviation) in height (6.70 cm) were 0.71 (0.54 to 0.94) for overweight (BMI ≥ 25 kg/m2) and 1.05 (0.87 to 1.27) for non-overweight (BMI < 25 kg/m2) men.Conclusion
Independent from classical cardiovascular risk factors, height was found to be inversely associated with carotid atherosclerosis for overweight but not for non-overweight men. 相似文献29.
Phylogeographic insights into the invasion history and secondary spread of the signal crayfish in Japan
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Nisikawa Usio Noriko Azuma Eric R. Larson Cathryn L. Abbott Julian D. Olden Hiromi Akanuma Kenzi Takamura Noriko Takamura 《Ecology and evolution》2016,6(15):5366-5382
Successful invasion by nonindigenous species is often attributed to high propagule pressure, yet some foreign species become widespread despite showing reduced genetic variation due to founder effects. The signal crayfish (Pacifastacus leniusculus) is one such example, where rapid spread across Japan in recent decades is believed to be the result of only three founding populations. To infer the history and explore the success of this remarkable crayfish invasion, we combined detailed phylogeographical and morphological analyses conducted in both the introduced and native ranges. We sequenced 16S mitochondrial DNA of signal crayfish from across the introduced range in Japan (537 samples, 20 sites) and the native range in western North America (700 samples, 50 sites). Because chela size is often related to aggressive behavior in crayfish, and hence, their invasion success, we also measured chela size of a subset of specimens in both introduced and native ranges. Genetic diversity of introduced signal crayfish populations was as high as that of the dominant phylogeographic group in the native range, suggesting high propagule pressure during invasion. More recently established crayfish populations in Japan that originated through secondary spread from one of the founding populations exhibit reduced genetic diversity relative to older populations, probably as a result of founder effects. However, these newer populations also show larger chela size, consistent with expectations of rapid adaptations or phenotypic responses during the invasion process. Introduced signal crayfish populations in Japan originate from multiple source populations from a wide geographic range in the native range of western North America. A combination of high genetic diversity, especially for older populations in the invasive range, and rapid adaptation to colonization, manifested as larger chela in recent invasions, likely contribute to invasion success of signal crayfish in Japan. 相似文献
30.
Katsunobu Sawaki Yoshiharu Sawaki Chen-Ri Zhao Yuriko Kobayashi Hiroyuki Koyama 《Plant and Soil》2016,406(1-2):131-143