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991.
Tetsuo Satch 《Life sciences》1973,13(9):1181-1188
Inhibitory effect of 7 organophosphorus compounds on the liver isocarboxazid amidase was studied in rats. This enzyme is more sensitive to the relatively less toxic compounds, i.e., Sumithion®, malathion and TOTP than to the more toxic ones susch as parathion, paraoxon and EPN. As little as 0.5 mg/kg of Sumithion inhibited this arylamidase activity by approx. 28% in male and 37% in female rats. TOTP completely inhibited the arylamidase in a dose of 20 mg/kg, moreover, a significant sex difference in the TOTP-induced inhibition of the enzyme was observed. 相似文献
992.
993.
Ken Tokizawa Shinichi Sawada Tatsuo Oka Akinori Yasuda Tetsuo Tai Hirofumi Ida Kazumi Nakayama 《International journal of biometeorology》2014,58(9):1919-1925
This study compared heat strain during walking while wearing impermeable protective suits between fan-precooling and nonprecooling conditions. Six males engaged in 60 min of walking at a moderate speed (~2.5 km/h) in a hot environment (37 °C, 40 % relative humidity). Fanning using a fan (4.5 m/s) and spraying water over the body before wearing the suits produced significantly lower rectal temperature before the walking (37.3?±?0.1 °C vs. 37.0?±?0.1 °C, P?0.05). In addition, whilst walking, rectal temperature was significantly lower in the precooling condition (maximum difference: 0.4 °C at 15 min of walking; 38.0?±?0.1 °C vs. 37.8?±?0.1 °C at the end of walking, P?0.05). Although skin temperature decreased during fanning, no difference was observed during walking. Heart rate was lower in the precooling condition during the early stages of walking. Thermal and fatigue perceptions whilst walking did not differ between the conditions. Body weight loss was significantly lower in the precooling condition. These results may indicate that fan precooling attenuates exertional heat strain while wearing impermeable protective clothing. The fan-cooling method is practical, convenient, and yields lower heat strain during prolonged moderate exertion. 相似文献
994.
Kouichi Mizuno Masahiro Matsuzaki Shiho Kanazawa Tetsuo Tokiwano Yuko Yoshizawa Misako Kato 《Biochemical and biophysical research communications》2014
Trigonelline (N-methylnicotinate), a member of the pyridine alkaloids, accumulates in coffee beans along with caffeine. The biosynthetic pathway of trigonelline is not fully elucidated. While it is quite likely that the production of trigonelline from nicotinate is catalyzed by N-methyltransferase, as is caffeine synthase (CS), the enzyme(s) and gene(s) involved in N-methylation have not yet been characterized. It should be noted that, similar to caffeine, trigonelline accumulation is initiated during the development of coffee fruits. Interestingly, the expression profiles for two genes homologous to caffeine synthases were similar to the accumulation profile of trigonelline. We presumed that these two CS-homologous genes encoded trigonelline synthases. These genes were then expressed in Escherichiacoli, and the resulting recombinant enzymes that were obtained were characterized. Consequently, using the N-methyltransferase assay with S-adenosyl[methyl-14C]methionine, it was confirmed that these recombinant enzymes catalyzed the conversion of nicotinate to trigonelline, coffee trigonelline synthases (termed CTgS1 and CTgS2) were highly identical (over 95% identity) to each other. The sequence homology between the CTgSs and coffee CCS1 was 82%. The pH-dependent activity curve of CTgS1 and CTgS2 revealed optimum activity at pH 7.5. Nicotinate was the specific methyl acceptor for CTgSs, and no activity was detected with any other nicotinate derivatives, or with any of the typical substrates of B′-MTs. It was concluded that CTgSs have strict substrate specificity. The Km values of CTgS1 and CTgS2 were 121 and 184 μM with nicotinic acid as a substrate, and 68 and 120 μM with S-adenosyl-l-methionine as a substrate, respectively. 相似文献
995.
Ayaka Okamoto Tomohiro Asai Hiroki Kato Hidenori Ando Tetsuo Minamino Eisuke Mekada Naoto Oku 《Biochemical and biophysical research communications》2014
An Fab’ antibody against heparin-binding epidermal growth factor-like growth factor (HB-EGF) was applied to achieve advanced tumor-targeted delivery of siRNA. Lipid nanoparticles (LNP) encapsulating siRNA (LNP-siRNA) were prepared, pegylated, and surface modified with Fab’ fragments of anti-HB-EGF antibody (αHB-EGF LNP-siRNA). αHB-EGF LNP-siRNA showed high-binding affinity to recombinant human HB-EGF in a Biacore assay. In addition, αHB-EGF LNP-siRNA selectively associated with cells expressing HB-EGF in vitro. Confocal microscopic images showed that siRNA formulated in αHB-EGF LNP-siRNA was efficiently internalized into MDA-MB-231 human breast cancer cells, on which HB-EGF is highly expressed. In addition, siRNA encapsulated in αHB-EGF LNP induced obvious suppression of both target mRNA and protein levels in MDA-MB-231 cells. These results indicate that αHB-EGF LNP have excellent potential to deliver siRNA to target cancer cells, resulting in effective gene silencing. 相似文献
996.
Megumi Tarui Hideo Shindou Kazuo Kumagai Ryo Morimoto Takeshi Harayama Tomomi Hashidate Hirotatsu Kojima Takayoshi Okabe Tetsuo Nagano Takahide Nagase Takao Shimizu 《Journal of lipid research》2014,55(7):1386-1396
Platelet-activating factor (PAF) is a potent pro-inflammatory phospholipid mediator. In response to extracellular stimuli, PAF is rapidly biosynthesized by lyso-PAF acetyltransferase (lyso-PAFAT). Previously, we identified two types of lyso-PAFATs: lysophosphatidylcholine acyltransferase (LPCAT)1, mostly expressed in the lungs where it produces PAF and dipalmitoyl-phosphatidylcholine essential for respiration, and LPCAT2, which biosynthesizes PAF and phosphatidylcholine (PC) in the inflammatory cells. Under inflammatory conditions, LPCAT2, but not LPCAT1, is activated and upregulated to produce PAF. Thus, it is important to develop inhibitors specific for LPCAT2 in order to ameliorate PAF-related inflammatory diseases. Here, we report the first identification of LPCAT2-specific inhibitors, N-phenylmaleimide derivatives, selected from a 174,000-compound library using fluorescence-based high-throughput screening followed by the evaluation of the effects on LPCAT1 and LPCAT2 activities, cell viability, and cellular PAF production. Selected compounds competed with acetyl-CoA for the inhibition of LPCAT2 lyso-PAFAT activity and suppressed PAF biosynthesis in mouse peritoneal macrophages stimulated with a calcium ionophore. These compounds had low inhibitory effects on LPCAT1 activity, indicating that adverse effects on respiratory functions may be avoided. The identified compounds and their derivatives will contribute to the development of novel drugs for PAF-related diseases and facilitate the analysis of LPCAT2 functions in phospholipid metabolism in vivo. 相似文献
997.
Katsutoshi Watanabe Seiichi Mori Tetsuo Tanaka Naoyuki Kanagawa Takahiko Itai Jyun-ichi Kitamura Noriyasu Suzuki Koji Tominaga Ryo Kakioka Ryoichi Tabata Tsukasa Abe Yushu Tashiro Yoshiki Hashimoto Jun Nakajima Norio Onikura 《Ichthyological Research》2014,61(4):352-360
The genetic population structure of the small cyprinid Hemigrammocypris rasborella, distributed widely in lowlands of western Japan, was examined using partial sequence data of mitochondrial DNA (mtDNA). Molecular phylogenetic analysis revealed that the populations of the western Kyushu region were markedly differentiated from all eastern populations, such that the groups would be comparable to different species; their divergence was inferred to have occurred in the Late Miocene–Pliocene. Also, a largely divergent mtDNA group (with divergence in the early Pleistocene) was found in the Sanyo and northeastern Shikoku regions, forming a secondary contact zone in the western Kinki with the eastern mtDNA group. To date, these aspects of the population structure of H. rasborella appear to be unique among lowland fishes in western Japan. Deeper understanding of the formation processes of freshwater faunas in western Japan will require further comparisons of the phylogeographic patterns and ecological traits of constituent species. 相似文献
998.
Inomata Yoshiyuki Echizenya Masaru Takeshima Masahiro Shimizu Kazumi Shimizu Tetsuo 《Sleep and biological rhythms》2014,12(4):289-296
Sleep and Biological Rhythms - The purposes of this study were to investigate the validity and reliability of the Japanese version of Horne and Östberg’s Morningness-Eveningness... 相似文献
999.
Adachi J Matsushita S Yoshioka N Funae R Fujita T Higuchi S Ueno Y 《Journal of lipid research》2004,45(5):967-971
Quantitative analysis of plasma phosphatidylcholine hydroperoxide (PCOOH) is an important step in evaluating the biochemical processes leading to oxidative injury. However, secondary products of lipid peroxidation are now used as indices. One hundred nine alcoholic patients, aged 22-81 years (mean +/- SEM, 52.0 +/- 1.3 years), and 21 healthy volunteers, aged 41-79 years (51.2 +/- 2.2 years), participated in this study. Plasma PCOOH was measured by HPLC with chemiluminescence detection. Plasma PCOOH concentration was significantly higher in alcoholic patients (46.1 +/- 4.1 pmol/ml) than in controls (15.6 +/- 1.8 pmol/ml). It was significantly higher in patients with blood alcohol (88.0 +/- 10.5 pmol/ml) than in those without alcohol (32.6 +/- 3.1 pmol/ml). The patients with high levels of aspartate aminotransferase, alanine aminotransferase, gamma-glutamyl transpeptidase (gamma-GTP), and triglyceride (TG) showed significantly higher PCOOH concentrations than did patients with normal levels. The PCOOH level was positively correlated with levels of gamma-GTP, HDL, blood alcohol concentration, and TG. Plasma PCOOH levels in 29 alcoholic patients after a 6 week abstinence were decreased significantly (22.8 +/- 11.1 pmol/ml), which was associated with improvement on liver function tests. This is the first measurement of plasma PCOOH in alcoholic patients. These results suggest the involvement of lipid peroxidation in alcohol-induced liver damage and confirm that the PCOOH plasma concentration is a new marker of alcohol consumption as well as oxidative stress in alcoholic patients. 相似文献
1000.
Masaharu Kitano Kazuki Urayama Yoshinobu Sakata Yasutaka Sonoda Kenji Ebihara Yuki Sago Hisashi Yoshikoshi Takuya Araki Daisuke Yasutake Hiroyuki Cho Tetsuo Kobayashi 《Biologia》2009,64(3):474-477
Water deficit and salt accumulation in soil presents serious problems to crop production in semi-arid regions. These problems
depend on the active transpiration stream and the selective absorption of ions by crop roots. In this study, a large sized
soil column system was used to examine the dynamics of water and ion transport and salt accumulation in soil layers. Special
reference was placed on the effects of the active and selective absorption by roots of different crops (i.e., corn plants,
sunflower plants and no plants). The column system was equipped with on-line systems for the control of groundwater level.
Soil water content sensors enabled time-course evaluations of the volumetric water content and hence upward flux of the groundwater
in the soils at different depths. Furthermore, the distribution and accumulation of ions in soil layers, plant organs and
xylem sap were analyzed using ion chromatography. In this column experiment, diurnal and longer term changes in water movement
and ion accumulation in soil, affected by root absorption characteristics of plants, were evaluated quantitatively. The results
demonstrated that the column system was applicable for the quantitative analysis of the effects of root absorption by different
crops on water deficit and salinization in soils. 相似文献