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31.
Eun Young Hwang Mi Suk Jeong Eun-Kyeong Park Jae Ho Kim Se Bok Jang 《Biochemical and biophysical research communications》2014
Periostin appears to be a unique extracellular protein secreted by fibroblasts that is upregulated following injury to the heart or changes in the environment. Periostin has the ability to associate with other critical extracellular matrix (ECM) regulators such as TGF-β, tenascin, and fibronectin, and is a critical regulator of fibrosis that functions by altering the deposition and attachment of collagen. Periostin is known to be highly expressed in carcinoma cells, but not in normal breast tissues. The protein has a structural similarity to insect fasciclin-1 (Fas 1) and can be induced by transforming growth factor-β (TGF-β) and bone morphogenetic protein (BMP)-2. To investigate the molecular interaction of periostin and bone morphogenetic protein, we modeled these three-dimensional structures and their binding sites. We demonstrated direct interaction between periostin and BMP1/2 in vitro using several biochemical and biophysical assays. We found that the structures of the first, second, and fourth Fas1 domains in periostin are similar to that of the fourth Fas 1 domain of TGFBIp. However, the structure of the third Fas 1 domain in periostin is different from those of the first, second, and fourth Fas1 domains, while it is similar to the NMR structure of Fasciclin-like protein from Rhodobacter sphaeroides. These results will useful in further functional analysis of the interaction of periostin and bone morphogenetic protein. 相似文献
32.
Jung Hwan Yoon Mi La Cho Yoo Jin Choi Ji Yeon Back Mi Kyung Park Suk Woo Lee Byung Joon Choi Hassan Ashktorab Duane T. Smoot Suk Woo Nam Jung Young Lee Won Sang Park 《Journal of cellular biochemistry》2013,114(8):1800-1809
Gastrokine 1 (GKN1) plays an important role in the gastric mucosal defense mechanism and also acts as a functional gastric tumor suppressor. In this study, we examined the effect of GKN1 on the expression of inflammatory mediators, including NF‐κB, COX‐2, and cytokines in GKN1‐transfected AGS cells and shGKN1‐transfected HFE‐145 cells. Lymphocyte migration and cell viability were also analyzed after treatment with GKN1 and inflammatory cytokines in AGS cells by transwell chemotaxis and an MTT assay, respectively. In GKN1‐transfected AGS cells, we observed inactivation and reduced expression of NF‐κB and COX‐2, whereas shGKN1‐transfected HFE‐145 cells showed activation and increased expression of NF‐κB and COX‐2. GKN1 expression induced production of inflammatory cytokines including IL‐8 and ‐17A, but decreased expression of IL‐6 and ‐10. We also found IL‐17A expression in 9 (13.6%) out of 166 gastric cancer tissues and its expression was closely associated with GKN1 expression. GKN1 also acted as a chemoattractant for the migration of Jurkat T cells and peripheral B lymphocytes in the transwell assay. In addition, GKN1 significantly reduced cell viability in both AGS and HFE‐145 cells. These data suggest that the GKN1 gene may inhibit progression of gastric epithelial cells to cancer cells by regulating NF‐κB signaling pathway and cytokine expression. J. Cell. Biochem. 114: 1800–1809, 2013. © 2013 Wiley Periodicals, Inc. 相似文献
33.
Tak H Jang E Kim SB Park J Suk J Yoon YS Ahn JK Lee JH Joe CO 《Cellular signalling》2007,19(11):2379-2387
The signal pathway by which 14-3-3epsilon inhibits cell migration induced by MAPK-activated protein kinase 5 (MK5) was investigated in cultured HeLa cells. Both in vivo and in vitro analyses have revealed that 14-3-3epsilon interacts with MK5. 14-3-3epsilon bound to MK5 inhibits the phosphorylation of HSP27, a known substrate of MK5. Disturbance of actin cytoskeleton organization by 14-3-3epsilon was shown in transfected cells transiently expressing 14-3-3epsilon as well as established cells stably expressing 14-3-3epsilon. Moreover, overexpression of 14-3-3epsilon resulted in the inhibition of cell migration induced by MK5 overexpression or TNFalpha treatment. Our results suggest that 14-3-3epsilon bound to MK5 inhibits cell migration by inhibiting the phosphorylation of HSP27 whose phosphorylation regulates F-actin polymerization, actin cytoskeleton organization and subsequent actinfilament dynamics. 相似文献
34.
Kang MJ Lee MH Shim JK Seo ST Shrestha R Cho MS Hahn JH Park DS 《Journal of microbiology and biotechnology》2007,17(11):1765-1771
A polymerase chain reaction (PCR)-based method was developed to detect the DNA of Ralstonia solanacearum, the causal agent of bacterial wilt in various crop plants. One pair of primers (RALSF and RALSR), designed using cytochrome c1 signal peptide sequences specific to R. solanacearum, produced a PCR product of 932 bp from 13 isolates of R. solanacearum from several countries. The primer specificity was then tested using DNA from 21 isolates of Ralstonia, Pseudomonas, Burkholderia, Xanthomonas, and Fusarium oxysporum f. sp. dianthi. The specificity of the cytochrome c1 signal peptide sequences in R. solanacearum was further confirmed by a DNA-dot blot analysis. Moreover, the primer pair was able to detect the pathogen in artificially inoculated soil and tomato plants. Therefore, the present results indicate that the primer pair can be effectively used for the detection of R. solanacearum in soil and host plants. 相似文献
35.
Byung Young Park Hyunghee Lee Sangee Woo Miso Yoon Jeongjun Kim Yeonhee Hong Hee Suk Lee Eun Kyu Park Jong Cheon Hahm Jin Woo Kim Soon Shik Shin Min-Young Kim Michung Yoon 《PloS one》2015,10(11)
It has been suggested that angiogenesis modulates adipogenesis and obesity. This study was undertaken to determine whether ALS-L1023 (ALS) prepared by a two-step organic solvent fractionation from Melissa leaves, which exhibits antiangiogenic activity, can regulate adipose tissue growth. The effects of ALS on angiogenesis and extracellular matrix remodeling were measured using in vitro assays. The effects of ALS on adipose tissue growth were investigated in high fat diet-induced obese mice. ALS inhibited VEGF- and bFGF-induced endothelial cell proliferation and suppressed matrix metalloproteinase (MMP) activity in vitro. Compared to obese control mice, administration of ALS to obese mice reduced body weight gain, adipose tissue mass and adipocyte size without affecting appetite. ALS treatment decreased blood vessel density and MMP activity in adipose tissues. ALS reduced the mRNA levels of angiogenic factors (VEGF-A and FGF-2) and MMPs (MMP-2 and MMP-9), whereas ALS increased the mRNA levels of angiogenic inhibitors (TSP-1, TIMP-1, and TIMP-2) in adipose tissues. The protein levels of VEGF, MMP-2 and MMP-9 were also decreased by ALS in adipose tissue. Metabolic changes in plasma lipids, liver triglycerides, and hepatic expression of fatty acid oxidation genes occurred during ALS-induced weight loss. These results suggest that ALS, which has antiangiogenic and MMP inhibitory activities, reduces adipose tissue mass in nutritionally obese mice, demonstrating that adipose tissue growth can be regulated by angiogenesis inhibitors. 相似文献
36.
Young Moon Choi Byoung Wan Lee Myung Sun Jung Hyun Soo Han Suk Hyun Kim Kaifeng Chen Dong Ha Kim Tony F. Heinz Shanhui Fan Jihye Lee Gi‐Ra Yi Jung Kyu Kim Jong Hyeok Park 《Liver Transplantation》2020,10(22)
N‐type metal oxides such as hematite (α‐Fe2O3) and bismuth vanadate (BiVO4) are promising candidate materials for efficient photoelectrochemical water splitting; however, their short minority carrier diffusion length and restricted carrier lifetime result in undesired rapid charge recombination. Herein, a 2D arranged globular Au nanosphere (NS) monolayer array with a highly ordered hexagonal hole pattern (hereafter, Au array) is introduced onto the surface of photoanodes comprised of metal oxide films via a facile drying and transfer‐printing process. Through plasmon‐induced resonance energy transfer, the Au array provides a strong electromagnetic field in the near‐surface area of the metal oxide film. The near‐field coupling interaction and amplification of the electromagnetic field suppress the charge recombination with long‐lived photogenerated holes and simultaneously enhance the light harvesting and charge transfer efficiencies. Consequently, an over 3.3‐fold higher photocurrent density at 1.23 V versus reversible hydrogen electrode (RHE) is achieved for the Au array/α‐Fe2O3. Furthermore, the high versatility of this transfer printing of Au arrays is demonstrated by introducing it on the molybdenum‐doped BiVO4 film, resulting in 1.5‐fold higher photocurrent density at 1.23 V versus RHE. The tailored metal film design can provide a potential strategy for the versatile application in various light‐mediated energy conversion and optoelectronic devices. 相似文献
37.
Hye Jin Chung Dong Woon Lee Hee Suk Yoon Sang Myeong Lee Chung Gyoo Park Ho Yul Choo 《Journal of Asia》2010,13(4):277-282
Out of some isolated Heterorhabditis bacteriophora from Korea, ecological study on two isolates which had different geographical features was investigated. That is, effects of temperature and dose on the pathogenicity and reproduction of two Korean isolates of H. bacteriophora were investigated using Galleria mellonella larvae in the laboratory. The median lethal dose (LD50) decreased with increasing temperature, but increased at 35 °C. The optimal temperatures for infection were 30 °C for H. bacteriophora Jeju strain and 24 °C for H. bacteriophora Hamyang strain. The median lethal time, LT50 of H. bacteriophora Hamyang strain was recorded at 13 °C to 35 °C and that of H. bacteriophora Jeju strain was recorded at 18 °C to 30 °C. The number of established nematodes in G. mellonella larvae was significantly different depending on temperature and dose. When G. mellonella larvae were exposed to 300 infective juveniles (IJs), mortality of G. mellonella gradually increased with exposure time with H. bacteriophora Jeju strain but not with H. bacteriophora Hamyang strain. 87.5% mortality of G. mellonella was recorded by H. bacteriophora Hamyang strain after 1440 min whereas 100% mortality was recorded by H. bacteriophora Jeju strain after 4320 min. The time from infection to the first emergence of nematodes decreased with increasing temperature. Duration of emergence of the two strains in the White traps also decreased with increasing temperature. The highest progeny numbers of H. bacteriophora Jeju strain were 264,602 while those of H. bacteriophora Hamyang strain were 275,744 at the rate of 160 IJs at 24 °C. 相似文献
38.
Background
The rate of incidentally diagnosed congenital heart disease (CHD) in adulthood has not been reported. The aim of this study was to investigate the detection rate of CHD in adults by routine, general health checkups.Methods
Data was acquired from 222,401 patients older than 19?years who participated in general health checkups from January 2010 to December 2016. We excluded persons who did not undergo echocardiography during the general health checkups, who underwent echocardiography prior to the health checkups, and who were previously diagnosed with CHD.Results
Among the 27,897 patients, who were included in the final analysis, 293 cases were newly diagnosed as CHD, and the overall detection rate was 1.05%. The mean age of patients with CHD was 48.7?±?21.5?years, and most of them were female (n?=?187, 63.8%). More than two-thirds were between the third and fifth decade of life, and only six patients (2.04%) were older than 70?years. The most common type was bicuspid aortic valve (n?=?155). Interestingly, Ebstein’s anomaly that required surgical repair was detected in five persons.Conclusions
During general health checkup, there were cases of severe CHD that required cardiac surgery upon diagnosis.39.
Summary Better production of pro-urokinase from human cell line was observed with 5% serum containing medium than 10% or serum free medium on Cytodex II under perfusion chemostat operations, showing 0.8×10–5 (IU/daycell) of maximum productivity at 0.020 (l/h) of dilution rate in 5% serum medium, which corresponds to 800 IU/mL at this dilution rate. Conversion of pro-urokinase was reduced in the serum-containing media. 相似文献
40.
Hyun Suk Shin Na Na Kim Gyung-Suk Kil 《Marine and Freshwater Behaviour and Physiology》2013,45(4):223-238
To establish the molecular basis of circadian rhythm control by melatonin receptors (MTs), we investigated the mitochondrial ribonucleic acid (mRNA) expressions of three types of MTs in different tissues of the olive flounder (Paralichthys olivaceus). All three types of MT mRNAs were expressed in the neural tissues, while MT1 mRNA was expressed in the peripheral tissues and MT2 and MT3 mRNAs were weakly expressed or undetected in these tissues. We observed increased MT mRNA expression in the neural tissues at night under both light–dark (LD) and constant dark (DD) conditions. Although the melatonin-treated cultured pineal gland samples showed similar diurnal variations with high-MT mRNA expression levels at night compared to those of untreated cultured pineal gland samples, the expression levels were considerably higher in the melatonin-treated samples. The plasma melatonin level also significantly increased at night. Under DD conditions, the expression patterns of MT mRNAs were similar to those under the LD photocycle, but the peak was lower and the circadian change patterns were less clear. These findings reinforce the hypothesis that MTs are active in processing light information, and that these genes are regulated by the circadian clock and light, thus suggesting that MTs play an important role in daily and circadian variations in the brain and retina of olive flounders. 相似文献