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91.
Jun Won Kim Bung-Nyun Kim Johanna Inhyang Kim Young Sik Lee Kyung Joon Min Hyun-Jin Kim Jaewon Lee 《PloS one》2015,10(11)
Introduction
Social network analysis has emerged as a promising tool in modern social psychology. This method can be used to examine friend-based social relationships in terms of network theory, with nodes representing individual students and ties representing relationships between students (e.g., friendships and kinships). Using social network analysis, we investigated whether greater severity of ADHD symptoms is correlated with weaker peer relationships among elementary school students.Methods
A total of 562 sixth-graders from two elementary schools (300 males) provided the names of their best friends (maximum 10 names). Their teachers rated each student’s ADHD symptoms using an ADHD rating scale.Results
The results showed that 10.2% of the students were at high risk for ADHD. Significant group differences were observed between the high-risk students and other students in two of the three network parameters (degree, centrality and closeness) used to assess friendship quality, with the high-risk group showing significantly lower values of degree and closeness compared to the other students. Moreover, negative correlations were found between the ADHD rating and two social network analysis parameters.Conclusion
Our findings suggest that the severity of ADHD symptoms is strongly correlated with the quality of social and interpersonal relationships in students with ADHD symptoms. 相似文献92.
Hye-In Kim Fu-Shi Quan Ji-Eun Kim Na-Rae Lee Hyun Ji Kim Su Ji Jo Chae-Min Lee Dae Sik Jang Kyung-Soo Inn 《Biochemical and biophysical research communications》2014
Extracts of Prunella vulgaris have been shown to exert antiestrogenic effects. To identify the compounds responsible for these actions, we isolated the constituents of P. vulgaris and tested their individual antiestrogenic effects. Rosmarinic acid, caffeic acid, ursolic acid (UA), oleanolic acid, hyperoside, rutin and betulinic acid (BA) were isolated from the flower stalks of P. vulgaris var. lilacina Nakai (Labiatae). Among these constituents, UA and BA showed significant antiestrogenic effects, measured as a decrease in the mRNA level of GREB1, an estrogen-responsive protein; the effects of BA were stronger than those of UA. UA and BA were capable of suppressing estrogen response element (ERE)-dependent luciferase activity and expression of estrogen-responsive genes in response to exposure to estradiol, further supporting the suppressive role of these compounds in estrogen-induced signaling. However, neither UA nor BA was capable of suppressing estrogen signaling in cells ectopically overexpressing estrogen receptor α (ERα). Furthermore, both mRNA and protein levels of ERα were reduced by treatment with UA or BA, suggesting that UA and BA inhibit estrogen signaling by suppressing the expression of ERα. Interestingly, both compounds enhanced prostate-specific antigen promoter activity. Collectively, these findings demonstrate that UA and BA are responsible for the antiestrogenic effects of P. vulgaris and suggest their potential use as therapeutic agents against estrogen-dependent tumors. 相似文献
93.
Lee HS Chang JH Ku SK 《Folia histochemica et cytobiologica / Polish Academy of Sciences, Polish Histochemical and Cytochemical Society》2010,48(3):387-393
The regional distribution and frequency of the pancreatic endocrine cells in the ddN mouse were studied using specific antisera against insulin, glucagon, somatostatin and human pancreatic polypeptide (hPP). In the pancreatic islets, most of insulin-immunoreactive (IR) cells were located in the central region, and glucagon-, somatostatin and hPP-IR cells were located in the peripheral region regardless of the lobe. In the splenic part, glucagon-IR cells were also located in the central regions, and more numerous somatostatin-IR cells were detected in the central regions as compared with the duo-denal part. hPP-IR cells were restricted to the peripheral regions in both lobes but more numerous cells were detected in the duodenal portion. In the exocrine parenchyma of the splenic lobe, only insulin- and glucagon-IR cells were detected but all four kinds of IR cells were observed in the duodenal portion. In addition, insulin and hPP-IR cells were also demonstrated in the pancreatic duct regions. In conclusion, some strain-dependent characteristic distributional patterns of pancreatic endocrine cells were found in the ddN mouse with somewhat different distributional patterns between the two pancreatic lobes. 相似文献
94.
Fenofibrate but not fenofibric acid inhibits 11beta-hydroxysteroid dehydrogenase 1 in C2C12 myotubes
Chi Hyun Kim Ravirala Ramu Jin Hee Ahn Myung Ae Bae Young Sik Cho 《Molecular and cellular biochemistry》2010,333(1-2):91-98
Microtubules (MTs) play an important role in cell division, and their functions are regulated by a set of microtubule-associated proteins (MAPs). Tubulin polymerization promoting protein family member 3 (TPPP3), also known as p20, is a new member of the tubulin polymerization promoting protein (TPPP) family. Previous studies have demonstrated that TPPP3 specifically binds to MTs and positively regulates MTs assembly, which leads to significant ultrastructural alterations of the MTs network. However, the physiological function of TPPP3 is still largely unknown. In the present study, we showed that knockdown of endogenous TPPP3 by RNA interference (RNAi) suppressed cell proliferation and induced cell cycle arrest in HeLa cells. Furthermore, we showed that the depletion of TPPP3 caused mitotic abnormalities, such as the formation of multipolar spindles and chromosome segregation errors, which lead to apoptosis in HeLa cells. Our study suggested that TPPP3 played a crucial role in cell mitosis by regulating centrosomes amplification and/or spindles translocation processes. 相似文献
95.
96.
Jaya Ram Simkhada Seung Sik Cho Hong Seok Choi Si Wouk Kim Hei Chan Lee Jae Kyung Sohng Jin Cheol Yoo 《Biotechnology and Bioprocess Engineering》2010,15(4):595-602
A phospholipase D (PLD628), constitutively secreted by Streptomyces sp. CS628, was purified by ion exchange with CM Trisacryl and gel filtration with Sepharose CL-6B. The enzyme production
was highest with peptone and starch as nitrogen and carbon sources, and at 30°C with an initial medium pH of 7.5. Molecular
weight, optimum pH, optimum temperature, pH stability, and thermostability of the enzyme were 50 kDa, pH 9.6, 30°C, pH 5.7
∼ 10.6 and ≤30°C, respectively. Detergents and metal ions had varied effects on the enzyme activity. Importantly, PLD628 could not catalyze transphosphatidylation of glycerol, L-serine, myo-inositol or ethanolamine, which are extensively used to assess the activity, suggesting that PLD628 lacks the transphosphatidylation activity. PLD628 could be a novel PLD based on its biochemical characteristics, which are significantly different from previously reported
PLDs, such as thermolability, highest activity at alkaline pH, and lack of transphosphatidylation activity. 相似文献
97.
Jehun Choi Sung Jin Bae Young Mi Ha Jae Kyung No Eun Kyeong Lee Jun Sik Lee Suhee Song Hyojin Lee Hongsuk Suh Byung Pal Yu Hae Young Chung 《Bioorganic & medicinal chemistry letters》2010,20(16):4882-4884
In searching for new agents with a depigmenting effect, we synthesized a derivative of resveratrol, 5-(6-hydroxy-2-naphthyl)-1,2,3-benzenetriol (5HNB) with a potent tyrosinase inhibitory activity. 5HNB inhibited mushroom tyrosinase with an IC50 value of 2.95 μM, which is more potent than the well-known anti-tyrosinase activity of kojic acid (IC50 = 38.24). The results of the enzymatic inhibition kinetics by Lineweaver–Burk analysis indicated 5HNB inhibits tyrosinase non-competitively when l-tyrosine was used as the substrate. Based on the strong inhibitory action of 5HNB, it is expected that 5HNB can suppress melanin production in which tyrosinase plays the essential role. Our expectation was confirmed by the experimentations with B16 melanoma cells in which 5HNB inhibited melanin production. We propose that 5HNB might have skin-whitening effects as well as therapeutic potential for treating skin pigmentation disorders. 相似文献
98.
Bon‐A Cho Nam‐Hyuk Cho Chan‐Ki Min Se‐Yoon Kim Jae‐Seong Yang Jung Rok Lee Jin Woo Jung Won‐Chul Lee Kijeong Kim Mi‐Kyung Lee Sanguk Kim Kwang Pyo Kim Seung‐Yong Seong Myung‐Sik Choi Ik‐Sang Kim 《Proteomics》2010,10(8):1699-1715
Orientia tsutsugamushi, an obligate intracellular bacterium, is the causative agent of Scrub typhus. The control mechanisms for bacterial gene expression are largely unknown. Here, the global gene expression of O. tsutsugamushi within eukaryotic cells was examined using a microarray and proteomic approaches for the first time. These approaches identified 643 genes, corresponding to approximately 30% of the genes encoded in the genome. The majority of expressed genes belonged to several functional categories including protein translation, protein processing/secretion, and replication/repair. We also searched the conserved sequence blocks (CSBs) in the O. tsutsugamushi genome which is unique in that up to 40% of its genome consists of dispersed repeated sequences. Although extensive shuffling of genomic sequences was observed between two different strains, 204 CSBs, covering 48% of the genome, were identified. When combining the data of CSBs and global gene expression, the CSBs correlates well with the location of expressed genes, suggesting the functional conservation between gene expression and genomic location. Finally, we compared the gene expression of the bacteria‐infected fibroblasts and macrophages using microarray analysis. Some major changes were the downregulation of genes involved in translation, protein processing and secretion, which correlated with the reduction in bacterial translation rates and growth within macrophages. 相似文献
99.
You Jin Lee Sun Young Park Sun Gun Kim Jum Soon Kang Sik Yoon Young Hun Kim Young-Whan Choi 《Biochemical and biophysical research communications》2010,391(4):1687-1692
A novel α-iso-cubebenol, which has anti-inflammatory effects in lipopolysaccharide (LPS)-treated RAW 264.7 macrophages, was isolated from the fruits of Schisandra chinensis. α-iso-cubebenol inhibited LPS-induced nitric oxide (NO) and prostaglandin E2 (PGE2) production. Consistent with these findings, α-iso-cubebenol also reduced the LPS-induced expression of inducible nitric oxide synthase and cyclooxygenase-2 at the protein and mRNA levels in a concentration-dependent manner. α-iso-cubebenol also inhibited LPS-induced nuclear translocation of the NF-κB p65 subunit. Furthermore, α-iso-cubebenol suppressed the phosphorylation of ERK, JNK, and p38 kinase induced by LPS. Since the novel α-iso-cubebenol blocked the production of several pro-inflammatory mediators induced by LPS in macrophages, the molecule can be useful material for the development of anti-inflammatory agents against bacterial infections or endotoxin. 相似文献
100.
We investigated the spatial and temporal distribution of xylans in the cell walls of differentiating earlywood tracheids of
Cryptomeria japonica using two different types of monoclonal antibodies (LM10 and LM11) combined with immunomicroscopy. Xylans were first deposited
in the corner of the S1 layer in the early stages of S1 formation in tracheids. Cell corner middle lamella also showed strong xylan labeling from the early stage of cell wall formation.
During secondary cell wall formation, the innermost layer and the boundary between the S1 and S2 layers (S1/S2 region) showed weaker labeling than other parts of the cell wall. However, mature tracheids had an almost uniform distribution
of xylans throughout the entire cell wall. Xylan localization labeled with LM10 antibody was stronger in the outer S2 layer than in the inner layer, whereas xylans labeled with LM11 antibody were almost uniformly distributed in the S2 layer. In addition, the LM10 antibody showed almost no xylan labeling in the S1/S2 region, whereas the LM11 antibody revealed strong xylan labeling in the S1/S2 region. These findings suggest that structurally different types of xylans may be deposited in the tracheid cell wall depending
on the developmental stage of, or location in, the cell wall. Our study also indicates that deposition of xylans in the early
stages of tracheid cell wall formation may be spatially consistent with the early stage of lignin deposition in the tracheid
cell wall. 相似文献