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91.
Mutations in the CFTR gene that lead to premature stop codons or splicing defects cause cystic fibrosis (CF) and are not amenable to treatment by small-molecule modulators. Here, we investigate the use of adenine base editor (ABE) ribonucleoproteins (RNPs) that convert A•T to G•C base pairs as a therapeutic strategy for three CF-causing mutations. Using ABE RNPs, we corrected in human airway epithelial cells premature stop codon mutations (R553X and W1282X) and a splice-site mutation (3849 + 10 kb C > T). Following ABE delivery, DNA sequencing revealed correction of these pathogenic mutations at efficiencies that reached 38–82% with minimal bystander edits or indels. This range of editing was sufficient to attain functional correction of CFTR-dependent anion channel activity in primary epithelial cells from CF patients and in a CF patient-derived cell line. These results demonstrate the utility of base editor RNPs to repair CFTR mutations that are not currently treatable with approved therapeutics.  相似文献   
92.
58 NHL-patients (9 large cell centrocytic, 18 centroblastic, 16 immunoblastic, 15 lymphoblastic lymphomas) were treated immediately after diagnosis with CHOP-chemotherapy regardless of the extent of disease. Because of the advanced age of the majority of patients (median age 61 years, range 22-85 years) a reduced dose in the first two cycles was administered. Statistically significant prognostic variables influencing survival were the following: histologic subtypes according to the Kiel-classification (p less than 0,05), B-symptoms (p less than 0,001), blood sedimentation rate (p less than 0,02) and LDH (p less than 0,0005). With regard to prognosis there was no difference between patients over 60 years of age and younger ones (p less than 0,4). Patients achieving complete remission survived significantly longer (p less than 0,0001). Ann Arbor stages were of limited value, since patients with CS II disease and accumulation of risk factors (B-symptoms, abdominal disease, bulky tumor masses) showed a poorer outcome than patients with CS III who did not have these risk factors. A risk factor score summarizing features influencing prognosis is described and might be a useful tool in stratifying the heterogeneous group of NHL with unfavorable prognosis.  相似文献   
93.
Membranes from rat liver were analysed under reducing conditions. The components of the soluble membranes responsible for the binding of acetylated low density lipoprotein (acetyl-LDL) and maleylated bovine serum albumin (Mal-BSA) were chromatographed on a polyethyleneimine-cellulose column and subsequently separated by gel electrophoresis. For both ligands a major binding protein (Mr = 35,000) was revealed by ligand blotting. A minor protein (Mr greater than 67,000) exhibited little binding. The Scatchard plot of the 131I-Mal-BSA binding data of the 35 kDa protein was linear, with a Kd of 17.3 nM. High concentrations of acetyl-LDL competed for half of the 131I-Mal-BSA binding. Excessive Mal-BSA competed for all the visible acetyl-LDL binding. The findings indicate the existence, in the reduced hepatic membrane, of a 35 kDa protein that has two binding sites for 131I-Mal-BSA and one binding site for acetyl-LDL.  相似文献   
94.
Primary cultures of rat hepatocytes grown in a serum-free medium supplemented with [35S]sulfate synthesize 35S-labelled glycosaminoglycans at an almost constant rate for 58 h. Approx. 57% of the newly synthesized 35S-labelled glycosaminoglycans remain within the hepatocytes, approx. 30% become associated with the cell surface and only 13% are secreted into the medium. The amount of cell-surface-associated 35S-labelled glycosaminoglycans became constant within 36 h, whereas no equilibrium was reached in the intra- and extracellular pool. During a 24 h chase more than 50% of the intracellular and cell-surface-associated 35S-labelled glycosaminoglycans disappears, more than 80% of this material is degraded and radioactivity is recovered as inorganic sulfate. A minor part is released into the medium in a macromolecular form. Heparan sulfate accounts for more than 95% of the 35S-labelled glycosaminoglycans in each of the three pools. It is distinguished from heparan sulfates from other sources by the presence of unsubstituted glucosamine residues. In all three pools, heparan sulfate chains of mean molecular weights between 24 000 and 30 000 are part of an alkali labile proteoglycan. Intra- and extracellularly, however, part of the heparan sulfate appears to have little, if any, protein attached. Hepatocytes contain heparan sulfate-degrading endoglycosidase activity, which may contribute to the variation of molecular weights observed for the heparan sulfate.  相似文献   
95.
Ni(II) complexes of ortho-naphthaquinone thiosemicarbazone and semicarbazone were synthesized and spectroscopically characterized. The X-ray crystal structure of both the complexes describe a distorted octahedral coordination with two tridentate mono-deprotonated ligands. In vitro anticancer studies on MCF-7 human breast cancer cells reveal that the semicarbazone derivative along with its nickel complex is more active in the inhibition of cell proliferation than the thiosemicarbazone analogue.  相似文献   
96.
Vectors derived from lentiviruses provide a promising gene delivery system. We examined the in vivo gene transfer efficiency and tissue or cell tropism of a feline immunodeficiency virus (FIV)-based lentiviral vector pseudotyped with the glycoproteins from Ross River Virus (RRV). RRV glycoproteins were efficiently incorporated into FIV virions, generating preparations of FIV vector, which after concentration attain titers up to 1.5 x 10(8) TU/ml. After systemic administration, RRV-pseudotyped FIV vectors (RRV/FIV) predominantly transduced the liver of recipient mice. Transduction efficiency in the liver with the RRV/FIV was ca. 20-fold higher than that achieved with the vesicular stomatitis virus G protein (VSV-G) pseudotype. Moreover, in comparison to VSV-G, the RRV glycoproteins caused less cytotoxicity, as determined from the levels of glutamic pyruvic transaminase and glutamic oxalacetic transaminase in serum. Although hepatocytes were the main liver cell type transduced, nonhepatocytes (mainly Kupffer cells) were also transduced. The percentages of the transduced nonhepatocytes were comparable between RRV and VSV-G pseudotypes and did not correlate with the production of antibody against the transgene product. After injection into brain, RRV/FIV preferentially transduced neuroglial cells (astrocytes and oligodendrocytes). In contrast to the VSV-G protein that targets predominantly neurons, <10% of the brain cells transduced with the RRV pseudotyped vector were neurons. Finally, the gene transfer efficiencies of RRV/FIV after direct application to skeletal muscle or airway were also examined and, although transgene-expressing cells were detected, their proportions were low. Our data support the utility of RRV glycoprotein-pseudotyped FIV lentiviral vectors for hepatocyte- and neuroglia-related disease applications.  相似文献   
97.
The thiosemicarbazone derivative of 9,10-phenanthrenequinone, 1, and its metal complexes were synthesized. The X-ray crystal structure for 1 confirms the presence of the E tautomeric arrangement in this compound. Its copper complex shows 1:1 stoichiometry while nickel and cobalt compounds show 1:2 stoichiometry. The X-ray crystal structure of the nickel complex indicates two tridentate ligands coordinating in the thiolato form yielding an octahedral geometry for the 'mer' isomer. The copper complex exhibits maximum antiproliferative activity against human breast cancer cell-line, T47D probably due to inhibition of steroid binding to the cognitive receptor or by preventing dimerization of the estrogen receptor.  相似文献   
98.
99.
Physical fatty acid deficiency signs in children with ADHD symptoms   总被引:1,自引:1,他引:0  
Fatty acid deficiency symptoms (FADS) of dry hair and skin, frequent thirst and urination have been observed to be higher in children with attention deficit hyperactivity disorder (ADHD). Two studies investigated FADS in 7-12-year-old children; Study 1 in a general population (N=347) and Study 2 in children with ADHD symptoms (N=104). Correlations between FADS and ADHD-related symptoms were found at baseline in Study 1 but not Study 2. FADS did not improve after supplementation with omega-3 and omega-6 polyunsaturated fatty acids (PUFA) versus placebo after 15 weeks in Study 2, and were not related to improvements in ADHD symptoms in the PUFA groups. However, FADS did improve in all groups, possibly attributable to the linoleic acid present in both the PUFA and placebo (palm oil) supplements. FADS are not a reliable selection criterion for children with ADHD who might benefit from omega-3 PUFA supplementation.  相似文献   
100.
Individual differences in behaviour are ubiquitous in nature. Despite the likely role of selection in maintaining these differences, there are few demonstrations of their fitness consequences in wild populations and, consequently, the mechanisms that link behavioural variation to variation in fitness are poorly understood. Specifically, the consequences of consistent individual differences in behaviour for the evolution of social and mating strategies have rarely been considered. We examined the functional links between variation in female aggression and her social and mating strategies in a wild population of the social lizard Egernia whitii. We show that female Egernia exhibit temporally consistent aggressive phenotypes, which are unrelated to body size, territory size or social density. A female''s aggressive phenotype, however, has strong links to her mode of paternity acquisition (within- versus extra-pair paternity), with more aggressive females having more offspring sired by extra-pair males than less aggressive females. We discuss the potential mechanisms by which female aggression could underpin mating strategies, such as the pursuit/acceptance of extra-pair copulations. We propose that a deeper understanding of the evolution and maintenance of social and mating systems may result from an explicit focus on individual-level female behavioural phenotypes and their relationship with key reproductive strategies.  相似文献   
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