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101.
OBJECTIVE--To study the association between upper and lower respiratory viral infections and acute exacerbations of asthma in schoolchildren in the community. DESIGN--Community based 13 month longitudinal study using diary card respiratory symptom and peak expiratory flow monitoring to allow early sampling for viruses. SUBJECTS--108 Children aged 9-11 years who had reported wheeze or cough, or both, in a questionnaire. SETTING--Southampton and surrounding community. MAIN OUTCOME MEASURES--Upper and lower respiratory viral infections detected by polymerase chain reaction or conventional methods, reported exacerbations of asthma, computer identified episodes of respiratory tract symptoms or peak flow reductions. RESULTS--Viruses were detected in 80% of reported episodes of reduced peak expiratory flow, 80% of reported episodes of wheeze, and in 85% of reported episodes of upper respiratory symptoms, cough, wheeze, and a fall in peak expiratory flow. The median duration of reported falls in peak expiratory flow was 14 days, and the median maximum fall in peak expiratory flow was 81 l/min. The most commonly identified virus type was rhinovirus. CONCLUSIONS--This study supports the hypothesis that upper respiratory viral infections are associated with 80-85% of asthma exacerbations in school age children.  相似文献   
102.
We collected several individuals of the Slaty-bellied Tesia Tesia olivea in the temperate rain forest of the sub-Himalayan region of northeastern Burma/Myanmar in February/March 2004 and March 2006. Subsequent comparison of these with T. olivea from northeastern India and northern Thailand revealed that while our northeastern Burma/Myanmar birds were similar to those from northeastern India, specimens of both populations were distinctly different from T. olivea from Chiang Mai Province of northern Thailand and northern Vietnam. Herein, we designate the latter populations as members of a new subspecies of T. olivea based on analyses of variations in morphometric characters, plumage, song, and mitochondrial (mt)DNA sequence.  相似文献   
103.
The protooncogene product Myc associates with many proteins. The isolation of the mouse MM-1; c-Myc binding protein (Myc-Modulator 1) cDNA is described. The cDNA contains a 462 bp open reading frame that encodes a polypeptide of 154 amino acid residues. The deduced amino acid sequence indicates that mouse MM-1 has a 99% identity with the sequence of human MM-1. The expression of mouse MM-1 mRNA was detected in the fetal liver, but its level was 3-fold higher than that in the normal adult liver, and was slightly increased after a partial hepatectomy. It is expressed widely in a variety of adult mouse tissues. Thus, MM-1 may play a role in liver development and growth. A bioinformatics analysis indicates that mouse MM-1 gene consists of 6 exons. Furthermore, the chromosomal location of the mouse MM-1 gene was on the F2-F3 band of chromosome 15, as determined by fluorescence in situ hybridization. The nucleotide sequence data reported in this paper appear in DDBJ, EMBL, and the GenBank nucloetide sequence databases with the following accession number, AF108357.  相似文献   
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Some mycobacterial infections, such as tuberculosis, are characterized by apoptosis of infected or by-stander mononuclear immune cells. For localized (paucibacillary, PB) and disseminated (multibacillary, MB) leprosy, characterized by polarized Th1-like vs. Th2-like immune responses, respectively, little is known about lesional apoptosis. We analyzed sections of paraffin-embedded, untreated leprosy lesions from 21 patients by an indirect immunofluorescent terminal deoxynucleotide-transferase-mediated dUTP-digoxigenin nick end labeling (TUNEL) assay. Some TUNEL (+) PB sections were then reacted with phycoerythrin-conjugated (red) antibodies against T cells, monocytes, or antigen-presenting (Langerhans) cells. TUNEL (+) bodies were detected in 9 of 16 PB lesions (56%) and in 1 of 5 MB lesions (20%). Some TUNEL (+) bodies in PB disease were CD3+ (T cell), as well as CD4+ (T-helper) or CD8+ (T-cytotoxic). Apoptosis characterizes PB and MB leprosy lesions and may be more frequent in PB disease. In PB disease, some TUNEL (+) bodies may derive from T cells.  相似文献   
107.
In laboratory experiments, the antifouling (AF) properties of zinc oxide (ZnO) nanorod coatings were investigated using the marine bacterium Acinetobacter sp. AZ4C, larvae of the bryozoan Bugula neritina and the microalga Tetraselmis sp. ZnO nanorod coatings were fabricated on microscope glass substrata by a simple hydrothermal technique using two different molar concentrations (5 and 10?mM) of zinc precursors. These coatings were tested for 5?h under artificial sunlight (1060?W?m?2 or 530?W?m?2) and in the dark (no irradiation). In the presence of light, both the ZnO nanorod coatings significantly reduced the density of Acinetobacter sp. AZ4C and Tetraselmis sp. in comparison to the control (microscope glass substratum without a ZnO coating). High mortality and low settlement of B. neritina larvae was observed on ZnO nanorod coatings subjected to light irradiation. In darkness, neither mortality nor enhanced settlement of larvae was observed. Larvae of B. neritina were not affected by Zn2+ ions. The AF effect of the ZnO nanorod coatings was thus attributed to the reactive oxygen species (ROS) produced by photocatalysis. It was concluded that ZnO nanorod coatings effectively prevented marine micro and macrofouling in static conditions.  相似文献   
108.
Soil and hydroponic culture experiments were conducted to investigate the effects of phosphite (Phi) as phosphorus (P) fertilizer via root and foliar applications on the growth and P supply of komatsuna. In both experiments, root P treatments were combinations of Phi and phosphate (Pi) at different Pi:Phi ratios, for a total of high P level (92 mg P pot?1; the soil experiment) or low P level (0.05 mM P; the hydroponic experiment). Foliar P treatments were deionized water (control), a Pi solution and a Phi solution at low concentration of 0.05% P2O5. In both experiments, shoot dry weight of plants significantly decreased as Pi:Phi ratio decreased. In the soil experiment, plants grew abnormally at a Pi:Phi ratio of 25:75 and died when P was applied to soil entirely as Phi form (0:100 treatment). In the hydroponic experiment, no visible damage was found in shoot but root growth was strongly inhibited with severe damage symptoms at low Pi:Phi ratios. Total P concentration in plant decreased significantly with decreasing Pi:Phi ratio, especially in the hydroponic experiment. Foliar application of Phi although greatly increased total P of plants compared to that of Pi in both experiments, it did not improve but further decreased plant growth at low Pi:Phi ratios in the soil experiment and at all Pi:Phi ratios in the hydroponic experiment. The results of this study clearly indicated that Phi could not be used as P fertilizer by komatsuna plants via both application methods and could not substitute P at any rate at either low or high level. No beneficial effect of Phi was detected even when it was applied at low rate or applied in combination with Pi at different ratios. The effects of Phi were strongly dependent on the P nutrition status of plants; and plants that were not sufficiently fertilized with Pi may become vulnerable to Phi even at low levels.  相似文献   
109.
In this study, we used imaging and proteomics to identify the presence of virus-associated cellular proteins that may play a role in respiratory syncytial virus (RSV) maturation. Fluorescence microscopy of virus-infected cells revealed the presence of virus-induced cytoplasmic inclusion bodies and mature virus particles, the latter appearing as virus filaments. In situ electron tomography suggested that the virus filaments were complex structures that were able to package multiple copies of the virus genome. The virus particles were purified, and the protein content was analyzed by one-dimensional nano-LC MS/MS. In addition to all the major virus structural proteins, 25 cellular proteins were also detected, including proteins associated with the cortical actin network, energy pathways, and heat shock proteins (HSP70, HSC70, and HSP90). Representative actin-associated proteins, HSC70, and HSP90 were selected for further biological validation. The presence of β-actin, filamin-1, cofilin-1, HSC70, and HSP90 in the virus preparation was confirmed by immunoblotting using relevant antibodies. Immunofluorescence microscopy of infected cells stained with antibodies against relevant virus and cellular proteins confirmed the presence of these cellular proteins in the virus filaments and inclusion bodies. The relevance of HSP90 to virus infection was examined using the specific inhibitors 17-N-Allylamino-17-demethoxygeldanamycin. Although virus protein expression was largely unaffected by these drugs, we noted that the formation of virus particles was inhibited, and virus transmission was impaired, suggesting an important role for HSP90 in virus maturation. This study highlights the utility of proteomics in facilitating both our understanding of the role that cellular proteins play during RSV maturation and, by extrapolation, the identification of new potential targets for antiviral therapy.Respiratory syncytial virus (RSV)1 belongs to the paramyxovirus group of viruses, and it is the most important respiratory virus causing lower respiratory tract infection in young children and neonates. The mature RSV particle comprises a ribonucleoparticle (RNP) core formed by the interaction between the viral genomic RNA (vRNA), the nucleocapsid (N) protein (42 kDa), the phospho (P) protein (35 kDa), and the large (L) protein (250 kDa). The RNP core is visualized by electron microscopy as a strand of repeating N protein subunits that form a herringbone-like structure of ∼10–20 nm in diameter (1). Although the minimal functional polymerase activity requires an association between the N, P, and L proteins and the virus genome vRNA (24), additional viral proteins called the M2-1 protein (22 kDa), M2-2 protein, and M protein (28 kDa) regulate the activity of the polymerase (58). The virus is surrounded by a lipid envelope that is formed from the host cell during the budding process in which the three virus membrane proteins are inserted. The G protein (90 kDa) mediates attachment of the virus to the cell during virus entry (9), and the fusion (F) protein (10) mediates the fusion of the virus and host cell membranes during virus entry, whereas the role of the SH protein is currently unknown. In addition, two non-structural proteins called NS1 and NS2, which are thought not to be present in the virus particle but play a role in countering the host innate immune response (11), are expressed.During virus infection two distinct virus structures are formed, virus filaments and inclusion bodies. The virus filaments are membrane-bound structures that are ∼150–200 nm thick and can be up to 6 μm in length (1, 1216); they form at the sites of virus assembly and are the progeny viruses. The inclusion bodies form in the cytoplasm and can be several μm in diameter, consisting of accumulations of RNP cores (1719). Inclusion bodies are found in all RSV-infected tissue culture cells, and they have also been observed in biopsy material isolated from RSV-infected patients (20) suggesting a clinical relevance. Although the cellular processes that lead to assembly of the mature virus filaments are still poorly understood, the involvement of lipid raft microdomains and the cortical cytoskeleton network appear to play an important role in this process (16, 2125). For example, rhoA kinase is a raft-associated signaling molecule that is involved in regulating actin structure (26), and it has been implicated in virus filament formation (27, 28). Virus filament formation also requires phosphoinositide 3-kinase (PI3K) activity (25, 29, 30); PI3K is a raft-associated kinase activated by rhoA kinase (31). The identification of cellular proteins that interact with the virus particles should further facilitate the identification of the cellular pathways that are involved in RSV maturation. In this study, we examined virus-host cell interactions during RSV assembly using a combination of advanced imaging techniques and analyzed the protein content of purified virus particles by proteomics technology. Our analysis provides evidence that cellular proteins that regulate actin structures in the cell may also play an important role in formation of infectious RSV particles, and that the HSP90 protein plays an important role in the virus assembly process.  相似文献   
110.
Three new steroid saponins (3β,25R)‐spirost‐5‐en‐3‐yl 6‐deoxy‐α‐L ‐mannopyranosyl‐(1→2)‐[β‐D ‐glucopyranosyl‐(1→4)‐6‐deoxy‐α‐L ‐mannopyranosyl‐(1→3)]‐β‐D ‐glucopyranoside ( 1 ), (3β,22R,25R)‐26‐(β‐D ‐glucopyranosyloxy)‐22‐hydroxyfurost‐5‐en‐3‐yl 6‐deoxy‐α‐L ‐mannopyranosyl‐(1→2)‐[6‐deoxy‐α‐L ‐mannopyranosyl‐(1→3)]‐β‐D ‐glucopyranoside ( 3 ), and (3β,22R,25R)‐26‐(β‐D ‐glucopyranosyloxy)‐22‐hydroxyfurost‐5‐en‐3‐yl 6‐deoxy‐α‐L ‐mannopyranosyl‐(1→2)‐[β‐D ‐glucopyranosyl‐(1→4)‐6‐deoxy‐α‐L ‐mannopyranosyl‐(1→3)]‐β‐D ‐glucopyranoside ( 5 ), as well as the new pregnane glycoside (3β,16β)‐3‐{[6‐deoxy‐α‐L ‐mannopyranosyl‐(1→2)‐[6‐deoxy‐α‐L ‐mannopyranosyl‐(1→3)]‐β‐D ‐glucopyranosyl]oxy}‐20‐oxopregn‐5‐en‐16‐yl (4R)‐5‐(β‐D ‐glucopyranosyloxy)‐4‐methylpentanoate ( 6 ), were isolated from the rhizomes of Tacca integrifolia together with two known (25R) configurated steroid saponins (3β,25R)‐spirost‐5‐en‐3‐yl 6‐deoxy‐α‐L ‐mannopyranosyl‐(1→2)‐[6‐deoxy‐α‐L ‐mannopyranosyl‐(1→3)]‐β‐D ‐glucopyranoside ( 2 ) and (3β,22R,25R)‐26‐(β‐D ‐glucopyranosyloxy)‐22‐methoxyfurost‐5‐en‐3‐yl 6‐deoxy‐α‐L ‐mannopyranosyl‐(1→2)‐[6‐deoxy‐α‐L ‐mannopyranosyl‐(1→3)]‐β‐D ‐glucopyranoside ( 4 ). The cytotoxic activity of the isolated compounds was evaluated in HeLa cells and showed the highest cytotoxicity value for compound 2 with an IC50 of 1.2±0.4 μM . Intriguingly, while compounds 1 – 5 exhibited similar cytotoxic properties between 1.2±0.4 ( 2 ) and 4.0±0.6 μM ( 5 ), only compound 2 showed a significant microtubule‐stabilizing activity in vitro.  相似文献   
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