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61.
Yong Hwan Han Suhn Hee Kim Sung Zoo Kim Woo Hyun Park 《Journal of biochemical and molecular toxicology》2009,23(1):36-42
Pyrogallol (PG) is a polyphenol compound and has been known to be an O generator. We evaluated the effects of PG on the growth of human pulmonary A549 cells in relation to the cell cycle and apoptosis. Treatment with 50 or 100 μM PG significantly inhibited the cell growth of A549 for 72 h. DNA flow cytometric analysis indicated that PG slightly induced a G1 phase arrest of the cell cycle at 24 or 48 h, but did not induce the specific cell cycle arrest at 72 h. Intracellular GSH depletion was observed in PG‐treated cells. PG induced apoptosis in A549 cells, as evidenced by sub‐G1 cells, annexin V staining cells, and the loss of mitochondrial membrane potential (Δ Ψm). The intracellular ROS (reactive oxygen species) level including O increased in PG‐treated A549 cells at 24 and 48 h, and persisted at 72 h. The changes in GSH as well as ROS levels by PG affected the cell viability in A549 cells. In conclusion, PG inhibited the growth of human pulmonary A549 cells by inducing cell cycle arrest as well as triggering apoptosis. © 2009 Wiley Periodicals, Inc. J Biochem Mol Toxicol 23:36–42, 2009; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/jbt.20263 相似文献
62.
Bok JW Balajee SA Marr KA Andes D Nielsen KF Frisvad JC Keller NP 《Eukaryotic cell》2005,4(9):1574-1582
63.
64.
Abu Hena Mostafa Kamal Ki-Hyun Kim Kwang-Hyun Shin Hyung-Seok Seo Hisashi Tsujimoto Hwa-Young Heo Jong-Soon Choi Chul-Soo Park Sun-Hee Woo 《Journal of Plant Biology》2009,52(6):533-542
Glutenin is a major determinant of baking performance and viscoelasticity, which are responsible for high-quality bread with
a light porous crumb structure of a well-leavened loaf. We analyzed the diversity of glutenin genes from six wheat cultivars
(Korean cvs. Keumgang and Jinpum, Chinese cvs. China-108 and Yeonnon-78, and Japanese cvs. Norin-61 and Kantou-107). Glutenins
contain two types of isoforms such as high molecular weight glutenin subunit (HMW-GS) and low molecular weight glutenin subunit
(LMW-GS). Glutenin fractions were extracted from wheat endosperm using Osborne solubility method. A total of 217 protein spots
were separated on two-dimensional gel electrophoresis with isoelectric focusing (wide range of pH 3–10). The proteins spots
were subjected to tryptic digestion and identified by matrix assisted laser desorption/ionization–time of flight mass spectrometry.
HMW-GS (43 isoforms) and LMW-GS (seven isoforms) are directly responsible for producing high-quality bread and noodles. Likewise,
all the seed storage proteins are digested to provide nutrients for the embryo during seed germination and seedling growth.
We identified the diverse glutenin subunits in wheat cultivars and compared the gluten isoforms among different wheat cultivars
according to quality. This work gives an insight on the quality improvement in wheat crop. 相似文献
65.
Seung Pil Yun Jung Min Ryu Min Woo Jang Ho Jae Han 《Journal of cellular physiology》2011,226(2):559-571
Although many previous reports have examined the function of prostaglandin E2 (PGE2) in the migration and proliferation of various cell types, the role of the actin cytoskeleton in human mesenchymal stem cells (hMSCs) migration and proliferation has not been reported. The present study examined the involvement of profilin‐1 (Pfn‐1) and filamentous‐actin (F‐actin) in PGE2‐induced hMSC migration and proliferation and its related signal pathways. PGE2 (10?6 M) increased both cell migration and proliferation, and also increased E‐type prostaglandin receptor 2 (EP2) mRNA expression, β‐arrestin‐1 phosphorylation, and c‐Jun N‐terminal kinase (JNK) phosphorylation. Small interfering RNA (siRNA)‐mediated knockdown of β‐arrestin‐1 and JNK (‐1, ‐2, ‐3) inhibited PGE2‐induced growth of hMSCs. PGE2 also activated Pfn‐1, which was blocked by JNK siRNA, and induced F‐actin level and organization. Downregulation of Pfn‐1 by siRNA decreased the level and organization of F‐actin. In addition, specific siRNA for TRIO and F‐actin‐binding protein (TRIOBP) reduced the PGE2‐induced increase in hMSC migration and proliferation. Together, these experimental data demonstrate that PGE2 partially stimulates hMSCs migration and proliferation by interaction of Pfn‐1 and F‐actin via EP2 receptor‐dependent β‐arrestin‐1/JNK signaling pathways. J. Cell. Physiol. 226: 559–571, 2011. © 2010 Wiley‐Liss, Inc. 相似文献
66.
A mouse macrophage (M phi) hybridoma which produces a soluble factor responsible for the cooperation between M phi and spleen dendritic cells (DC) was constructed. The antigen-presenting activity and the stimulator cell activity in the allogeneic or syngeneic mixed leukocyte reaction of DC were significantly augmented when DC were incubated with the culture supernatant of the hybridoma treated with various stimulants including latex beads. The monokine present in the culture supernatant of the hybridoma, called dendritic cell-activating factor (DCAF), augmented the production of lymphocyte-activating factor by DC while Ia expression of DCAF-treated DC was not altered. DCAF had no effect on the antigen-presenting activity of peritoneal resident M phi or B cell blasts while the antigen-presenting activity of spleen M phi was enhanced, but the degree of the enhancement was much less than that of spleen DC. DCAF was found to have the following properties: its pI value is between pH 4 and 5; it is stable at pH 2 to 10; and it loses its activity on incubation at 75 C for 30 min. When the culture supernatant of the hybridoma stimulated with latex beads was subjected to gel filtration, the DCAF activity was detected in the 20 Kd to 25 Kd, 30 Kd to 40 Kd, and 50 Kd to 60 Kd molecular weight regions. The 30 Kd to 40 Kd fraction, which is the major peak fraction, was further purified by ion-exchange chromatography followed by gel-filtration chromatography. When each fraction was subjected to SDS-PAGE, a 30 Kd band corresponding to the DCAF activity was observed and DCAF was purified to about 90% purity. 相似文献
67.
Nayoung Kim Soo‐Heon Park Geom Seog Seo Sang Woo Lee Jae Woo Kim Kwang Jae Lee Won‐Chang Shin Tae Nyeun Kim Moo‐In Park Jong‐Jae Park Su Jin Hong Ki‐Nam Shim Sang Wook Kim Yong‐Woon Shin Young‐Woon Chang Hoon Jai Chun Ok‐Jae Lee Won‐Joong Jeon Chan‐Guk Park Chang‐Min Cho Cheol Hee Park Sun Young Won Gin Hyug Lee Kyung Sik Park Jeong Eun Shin Heung Up Kim Joon Yong Park Hiun Suk Chae Geun Am Song Jae Gyu Kim Byung Chul Yoon Sangyong Seol Hyun Chae Jung In‐Sik Chung 《Helicobacter》2008,13(6):542-549
Background and Aims: Lafutidine is a novel H2‐receptor antagonist with gastroprotective activity that includes enhancement of gastric mucosal blood flow. The aim of the present study was to test the efficacy of 7‐ or 14‐day lafutidine–clarithromycin–amoxicillin therapy versus a lansoprazole‐based regimen for Helicobacter pylori eradication. Methods: Four hundred and sixty‐three patients with H. pylori‐infected peptic ulcer disease were randomized to one of four regimens: (1) lafutidine (20 mg b.i.d.), clarithromycin (500 mg b.i.d.) and amoxicillin (1000 mg b.i.d.) for 7 days (the 7LFT group) or (2) for 14 days (the 14LFT group); (3) lansoprazole (30 mg b.i.d.), clarithromycin (500 mg b.i.d.), and amoxicillin (1000 mg b.i.d.) for 7 days (the 7LPZ group); or (4) for 14 days (the 14LPZ group). The eradication rates, drug compliance, and adverse effects among the four regimens were compared. Results: The eradication rates by the intention‐to‐treat and per‐protocol analyses in the 7LFT and 7LPZ groups were 76.5% and 81.6%, and 76.9% and 82.0% (p = .94 and .95), respectively. The eradication rates by intention‐to‐treat and per‐protocol analyses in the 14LFT and 14LPZ groups were 78.2% and 82.2%, and 80.4% and 85.9% (p = .70 and .49), respectively. The treatment duration for 7 days or 14 days did not affect the eradication rates. In addition, the adverse effect rates and discontinuation rates were similar among the four groups. Furthermore, the ulcer cure rate and symptom response rate were similar in the lafutidine and lansoprazole groups. Conclusion: The results of this study showed that lafutidine–clarithromycin–amoxicillin therapy was a safe and effective as lansoprazole‐based triple therapy for the eradication rate of H. pylori, and could be considered as an additional treatment option. 相似文献
68.
Using Escherichia coli cell-free protein synthesis system and aminoacylated amber suppressor tRNA, we successfully inserted an unnatural amino acid S-(2-nitrobenzyl)cysteine into human erythropoietin. Three different types of translation stop suppression were observed and each of the three types was easily discerned with SDS-PAGE. Optimal conditions were established for correct stop and programmed suppressions. Since this system differentiates proteins produced by misreading of codons from those produced by programmed suppression, we conclude that this cell-free translation system that we describe in this paper will be of a great use for future investigations on translation stop processes. 相似文献
69.
70.
Cho EJ Hwang HJ Kim SW Oh JY Baek YM Choi JW Bae SH Yun JW 《Applied microbiology and biotechnology》2007,75(6):1257-1265
The anti-diabetic activities of the exopolysaccharides (EPS) produced by submerged mycelial culture of two different mushrooms,
Tremella fuciformis and Phellinus baumii, in ob/ob mice were investigated. All the animals were randomly divided into three groups with seven animals in each group: The control
group received 0.9% NaCl solution; the diabetic groups were treated with EPS from T. fuciformis (Tf EPS) and P. baumii (Pb EPS) at the level of 200 mg/kg body weight using an oral zoned daily for 52 days. The plasma glucose levels in the EPS-fed
mice were substantially reduced by about 52% (Tf EPS) and 32% (Pb EPS), respectively, as compared to control mice. The results
of oral glucose tolerance test (OGTT) revealed that both EPS-fed groups significantly increased the glucose disposal after
52 days of EPS treatments. Furthermore, higher food efficiency ratios and reduced blood triglyceride levels were observed
in the EPS-treated groups. Because peroxisome proliferator-activated receptor gamma (PPAR-γ) is indeed a key regulator of
insulin action, we investigated the expression pattern of adipose tissue PPAR-γ messenger RNA (mRNA) and plasma levels of
PPAR-γ. It was revealed that PPAR-γ was significantly activated in response to EPS treatments. The results suggested that
both EPS exhibited considerable hypoglycemic effect and improved insulin sensitivity possibly through regulating PPAR-γ-mediated
lipid metabolism. Our results indicated that two mushroom-derived EPS might be developed as potential oral hypoglycemic agents
or functional foods for the management of non-insulin-dependent diabetes mellitus. 相似文献