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Lourival D. Possani Alejandro C. Alagón Paul L. Fletcher Bruce W. Erickson 《Archives of biochemistry and biophysics》1977,180(2):394-403
The water-soluble part of the dried venom from the scorpion, Tityus serrulatus Lutz and Mello (range, Southeastern Brazil), showed 16 polypeptide bands on polyacrylamide gel electrophoresis. This material exhibited toxic and hyaluronidase activity but no phospholipase, phosphodiesterase, protease, or fibrinolytic activity. Fractionation on glycinamide-treated Sephadex G-50 afforded three protein fractions, which were non-toxic, equitoxic, and three times more toxic than the water-soluble venom. Subsequent separation of the toxic fractions on carboxymethyl-cellulose with phosphate buffers furnished five toxic components, which were further purified on carboxymethyl-cellulose with a salt gradient in acetate buffer. Toxin γ, the major and most basic toxin, is a 62-residue protein that, unlike other scorpion toxins, contains methionine. Automated Edman degradation showed the amino-terminal sequence to be H-Lys-Glu-Gly-Tyr-Leu-Met-Asp-His-Glu-Gly-Cys-Lys-Leu-Ser-Cys-Phe-Ile-Arg-Pro-Ser-Gly-Tyr-Cys-Gly-Arg-Glu-Cys-Gly-Ile-. Toxin γ is the first example of a fifth structural type of mammalian toxin from scorpion venom. Its amino-terminal sequence shows greater homology with toxins similar to Centruroides suffusus suffusus toxin III and Androctonus australis toxin II than with toxins similar to A. australis toxin I or Bhutus occitanus tunetanus toxin I. 相似文献
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Molecular Biology Reports - Atherosclerosis and related cardiovascular diseases are among the most common causes of death worldwide. Unfolded protein response, also known as Endoplasmic... 相似文献
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Ozge Rencuzogulları Pınar Obakan Yerlikaya Ajda Çoker Gürkan Elif Damla Arısan Dilek Telci 《Journal of cellular biochemistry》2020,121(1):508-523
The mortality rate of pancreatic cancer has close parallels to its incidence rate because of limited therapeutics and lack of effective prognosis. Despite various novel chemotherapeutics combinations, the 5-year survival rate is still under 5%. In the current study, we aimed to modulate the aberrantly activated PI3K/AKT pathway and epithelial-mesenchymal transition (EMT) signaling with the treatment of CDK4/6 inhibitor PD-0332991 (palbociclib) in Panc-1 and MiaPaCa-2 pancreatic cancer cells. It was found that PD-0332991 effectively reduced cell viability and proliferation dose-dependently within 24 hours. In addition, PD-0332991 induced cell cycle arrest at the G1 phase by downregulation of aberrant expression of CDK4/6 through the dephosphorylation of Rb in each cell lines. Although PD-0332991 treatment increased epithelial markers and decreased mesenchymal markers, the nuclear translocation of β-catenin was not prevented by PD-0332991 treatment, especially in MiaPaCa-2 cells. Effects of PD-0332991 on the regulation of PI3K/AKT signaling and its downstream targets such as GSK-3 were cell type-dependent. Although the activity of AKT was inhibited in both cell lines, the phosphorylation of GSK-3β at Ser9 increased only in Panc-1. In conclusion, PD-0332991 induced cell cycle arrest and reduced the cell viability of Panc-1 and MiaPaCa-2 cells. However, PD-0332991 differentially affects the regulation of the PI3K/AKT pathway and EMT process in cells due to its distinct influence on Rb and GSK-3/β-catenin signaling. Understanding the effect of PD-0332991 on the aberrantly activated signaling axis may put forward a new therapeutic strategy to reduce the cell viability and metastatic process of pancreatic cancer. 相似文献
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Dilek Pandir Recep Sahingoz Fahriye Sumer Ercan 《Biocontrol Science and Technology》2013,23(12):1402-1411
This study investigated the effect of strong magnetic fields as insecticidal activity on Ephestia kuehniella (Zeller) (Lepidoptera: Pyralidae) larvae and eggs at different stages of development and their preference by the egg parasitoid, Trichogramma embryophagum Hartig (Hymenoptera: Trichogrammatidae). Eggs ranging in age from 24-h to 48-h and 72-h-old and larvae (1 to 2 days) were exposed to 1.4 Tesla (T) magnetic fields from a DC power supply at 50 Hz for different time periods (3, 6, 12, 24, 48 and 72 h). Twelve hours of exposure at 1.4 T was toxic to 24-h-old eggs of E. kuehniella. The 72-h-old host eggs treated with 1.4 T for 6–72 h were not significantly preferred by T. embryophagum. The magnetic field was toxic to 24-h-old eggs of E. kuehniella exposed to 1.4 T for 12. The treatment of magnetic fields on the 72-h-old host egg with 1.4 T at 6–72 h was not significantly preferred by T. embryophagum. Magnetization of 24-h-old eggs of E. kuehniella for 3 h could be effectively used with T. embryophagum as sterilised host eggs. These eggs were markedly preferred by T. embryophagum. The LT50 and LT99 values of magnetic fields at different egg stages of E. kuehniella, and larvae were measured. A level of 1.4 T at 72 h completely prevented the development of the larvae. There was no significant effect on larval survival at 1.4 T at 48 and 72 h. Increasing magnetic fields exposure times for eggs that were 24-h, 48-h and 72-h-old prevented larval emergence and increased their mortality rate. Consequently, magnetic fields could be used in controlling stored-product pest eggs and larvae of E. kuehniella. 相似文献
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Mehlika Dilek Altintop Belgin Sever Ahmet Özdemir Gökhan Kuş Pinar Oztopcu-Vatan Selda Kabadere 《Journal of enzyme inhibition and medicinal chemistry》2016,31(3):410-416
Fourteen new naphthalene-based thiosemicarbazone derivatives were designed as anticancer agents against LNCaP human prostate cancer cells and synthesized. MTT assay indicated that compounds 6, 8 and 11 exhibited inhibitory effect on LNCaP cells. Among these compounds, 4-(naphthalen-1-yl)-1-[1-(4-hydroxyphenyl)ethylidene)thiosemicarbazide (6), which caused more than 50% death on LNCaP cells, was chosen for flow cytometric analysis of apoptosis. Flow cytometric analysis pointed out that compound 6 also showed apoptotic effect on LNCaP cells. Compound 6 can be considered as a promising anticancer agent against LNCaP cells owing to its potent cytotoxic activity and apoptotic effect. 相似文献
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Ozaltin F Ibsirlioglu T Taskiran EZ Baydar DE Kaymaz F Buyukcelik M Kilic BD Balat A Iatropoulos P Asan E Akarsu NA Schaefer F Yilmaz E Bakkaloglu A;PodoNet Consortium 《American journal of human genetics》2011,(1):139-147
Idiopathic nephrotic syndrome (INS) is a genetically heterogeneous group of disorders characterized by proteinuria, hypoalbuminemia, and edema. Because it typically results in end-stage kidney disease, the steroid-resistant subtype (SRNS) of INS is especially important when it occurs in children. The present study included 29 affected and 22 normal individuals from 17 SRNS families; genome-wide analysis was performed with Affymetrix 250K SNP arrays followed by homozygosity mapping. A large homozygous stretch on chromosomal region 12p12 was identified in one consanguineous family with two affected siblings. Direct sequencing of protein tyrosine phosphatase receptor type O (PTPRO; also known as glomerular epithelial protein-1 [GLEPP1]) showed homozygous c.2627+1G>T donor splice-site mutation. This mutation causes skipping of the evolutionarily conserved exon 16 (p.Glu854_Trp876del) at the RNA level. Immunohistochemistry with GLEPP1 antibody showed a similar staining pattern in the podocytes of the diseased and control kidney tissues. We used a highly polymorphic intragenic DNA marker-D12S1303-to search for homozygosity in 120 Turkish and 13 non-Turkish individuals in the PodoNet registry. This analysis yielded 17 candidate families, and a distinct homozygous c.2745+1G>A donor splice-site mutation in PTPRO was further identified via DNA sequencing in a second Turkish family. This mutation causes skipping of exon 19, and this introduces a premature stop codon at the very beginning of exon 20 (p.Asn888Lysfs*3) and causes degradation of mRNA via nonsense-mediated decay. Immunohistochemical analysis showed complete absence of immunoreactive PTPRO. Ultrastructural alterations, such as diffuse foot process fusion and extensive microvillus transformation of podocytes, were observed via electron microscopy in both families. The present study introduces mutations in PTPRO as another cause of autosomal-recessive nephrotic syndrome. 相似文献