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11.
In the spinster (spin) mutant of Drosophila melanogaster, the extent of programmed cell death (PCD) in the abdominal ganglion 6 h after puparium formation (APF) is significantly reduced. The shortening of the abdominal ganglion, which is normally completed 48 h APF, does not occur. After eclosion, neurodegeneration accompanied by accumulation of autofluorescent materials is manifested in the central nervous system (CNS) of the spin mutant. The materials accumulated in the spin-mutant CNS contain a substance that is immunopositive to an antibody against GM2 ganglioside. Halving the dosage of three cell death genes, rpr, grim, and hid, blocks shortening of the abdominal ganglion and induces neurodegeneration accompanied by accumulation of autofluorescent materials in the adult CNS. These observations suggest that the primary action of the spin mutation is to reduce the extent of PCD 6 h APF, which concomitantly leads to a failure in shortening of the abdominal ganglion and to neurodegeneration of the adult CNS. Arch. 相似文献
12.
Shigehara T Mitsuhashi H Ota F Kuroiwa T Kaneko Y Ueki K Tsukada Y Maezawa A Nojima Y 《Life sciences》2002,70(19):2225-2232
Sulfite is a major air pollutant which can cause respiratory tract inflammation characterized by an influx of polymorphonuclear neutrophils (PMN). We have previously shown that human PMN can produce sulfite either spontaneously or in response to stimulation with lipopolysaccharide. We now demonstrate that sulfite activates PMN to adhere to immobilized fibrinogen via the beta2-integrin Mac-1 (CD11b/CD18). Mac-1 expression is not altered by treatment with this agent. Although unaffected by pertussis toxin, sulfite-triggered PMN adhesion was abrogated by pretreating cells with the membrane-impermeant sulfhydryl reagent 5,5'-dithiobis(2-nitrobenzoic acid) (DTNB), a modifier of thiol groups on the cell surface. These results suggest that sulfite-induced PMN adhesion is dependent on a modification of thiols at the cell surface. Given its potent antioxidant and antimicrobial activities, sulfite may act as an endogenous mediator in host defense and/or inflammation. 相似文献
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Lack of mannose-binding lectin-A enhances survival in a mouse model of acute septic peritonitis 总被引:8,自引:0,他引:8
Takahashi K Gordon J Liu H Sastry KN Epstein JE Motwani M Laursen I Thiel S Jensenius JC Carroll M Ezekowitz RA 《Microbes and infection / Institut Pasteur》2002,4(8):773-784
The mannose-binding lectin (MBL) (also known as the mannose-binding protein) is a serum protein that plays a role as an "ante-antibody" in innate immunity. In man, MBL is encoded by a single gene, whereas in mice there are two homologous proteins, MBL-A and MBL-C. In order to evaluate the relative roles of these two forms of MBL, we created MBL-A null mice that were MBL-C sufficient. We found MBL-A null mice had enhanced survival in a septic peritonitis model compared to wild-type mice and complement 3 null mice at 24 h, 48 h and 10 d (P < 0.05). Reconstitution of these mice with human MBL reversed the phenotype. Surviving mice had significantly decreased TNF-alpha and IL-6 levels in the blood and peritoneal cavity (P < 0.01). In vitro studies indicate that bacteria opsonized with MBL-A-deficient serum induced significantly less cytokine by peritoneal macrophages compared to those with wild-type serum. Our results indicate that MBL-A is a modulator of inflammation in vivo and in vitro in the mouse and that the role of MBL may extend beyond its role as an opsonin. 相似文献
14.
Phosphorylation of retinoblastoma-related protein by the cyclin D/cyclin-dependent kinase complex is activated at the G1/S-phase transition in tobacco 下载免费PDF全文
In mammals, D-type cyclin-associated kinases mainly regulate the G1/S transition by phosphorylating the retinoblastoma (Rb) protein. We previously demonstrated that in tobacco, cyclin D (Nicta; CycD3;3) is complexed with the PSTAIRE-containing cyclin-dependent kinase (CDKA) from tobacco. Here, we show that Nicta; CycD3;3-associated kinases phosphorylate both the tobacco Rb-related protein (NtRb1) and histone H1. Although NtRb1 kinase activity was detected only during the middle G1- to early S-phase, histone H1 kinase activity was observed as two peaks in G1- to S-phase and G2/M- to M-phase. Importantly, we show that the proportion of cells in the G1-phase was reduced in transgenic Bright Yellow-2 cells overexpressing Nicta; CycD3;3-GFP. Mutational analyses revealed that phosphorylation of Thr-191 in Nicta; CycD3;3 possibly is required for both full kinase activity and localization predominantly to the nucleus. These data suggest that Nicta; CycD3;3 acts as a rate-limiting regulator in the G1/S transition by forming active complexes with CDKA or its related kinases to phosphorylate Rb-related protein and potentially plays a novel role during G2/M and mitosis. 相似文献
15.
Ishimoto T Ninomiya K Miyaji K Uyeda A Kasai M Taguchi T 《Biochimica et biophysica acta》2002,1579(2-3):189-195
Although a subpopulation of mRNAs has been identified as translocated to the dendrites or the synaptic regions of neurons, the translocational mechanism has not been elucidated. To find mRNAs enriched in synapses, we compared the synaptosomal mRNAs with those from whole forebrain using differential display (DD). We cloned one of these mRNAs, which encoded a novel 31 kDa protein (PMES-2). PMES-2 mRNA was specifically transcribed in the brain and was present in the dendrites of the hippocampal neurons. PMES-2 protein was partly localized in the postsynaptic density. Although this protein is very similar to human NABC1 protein, its function is still unknown. 相似文献
16.
Hiroyuki Yamauchi Kazue Honma Kazuki Mochizuki 《Bioscience, biotechnology, and biochemistry》2018,82(7):1176-1179
Jejunal sodium/glucose co-transporter (Sglt1) displays circadian expression. The jejunum was collected every 4 h from mice, and we examined histone acetylation and binding of bromodomain-containing protein-4 (BRD4) around of the gene. Histone acetylation increased in the transcribed region of Sglt1 prior to induction of the gene. Furthermore, the binding of mRNA elongation factor around the gene showed circadian rhythm. 相似文献
17.
Flavia Kazue Ibuki Alyne Simões Fernando Neves Nogueira 《Cell biochemistry and function》2010,28(6):503-508
Hyperglycemia induces overproduction of superoxide and it is related to diabetic complications. In this study, we analyzed the antioxidant enzymatic defense and the lipid peroxidation of rat salivary glands in six different periods of diabetic condition. Ninety‐six rats were divided into 12 groups: C7/14/21/28/45/60 (non‐diabetic animals) and D7/14/21/28/45/60 (diabetic animals). Diabetes was induced by streptozotocin and the rats were euthanized after 7, 14, 21, 28, 45, or 60 days. Their parotid (PA) and submandibular (SM) glands were removed soon after the sacrifice and the total protein and malondialdehyde (MDA) concentrations, as well as, the superoxide dismutase (SOD), glutathione peroxidase (GPx), and catalase (CAT) activities were determined. Twenty‐one days after the diabetes induction, the SM glands showed an increase in SOD, CAT, and GPx activities, as well as, MDA concentration. Concerning the PA glands, an increase in the CAT activity and MDA content was observed throughout the observation period. The results suggest that diabetes can cause alterations on the salivary glands and that PA and SM glands react differently when exposed to diabetes condition. However, no impairment of antioxidant system was observed in the group whose diabetic condition had been induced 60 days earlier, herein named 60‐day group. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
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19.
Yukiko Hori Shuko Takeda Hansang Cho Susanne Wegmann Timothy M. Shoup Kazue Takahashi Daniel Irimia David R. Elmaleh Bradley T. Hyman Eloise Hudry 《The Journal of biological chemistry》2015,290(4):1966-1978
Interfering with the assembly of Amyloid β (Aβ) peptides from monomer to oligomeric species and fibrils or promoting their clearance from the brain are targets of anti-Aβ-directed therapies in Alzheimer disease. Here we demonstrate that cromolyn sodium (disodium cromoglycate), a Food and Drug Administration-approved drug already in use for the treatment of asthma, efficiently inhibits the aggregation of Aβ monomers into higher-order oligomers and fibrils in vitro without affecting Aβ production. In vivo, the levels of soluble Aβ are decreased by over 50% after only 1 week of daily intraperitoneally administered cromolyn sodium. Additional in vivo microdialysis studies also show that this compound decreases the half-life of soluble Aβ in the brain. These data suggest a clear effect of a peripherally administered, Food and Drug Administration-approved medication on Aβ economy, supporting further investigation of the potential long-term efficacy of cromolyn sodium in Alzheimer disease. 相似文献
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