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1.
Mammalian orthoreoviruses (reoviruses) are highly tractable experimental models for studies of double-stranded (ds) RNA virus replication and pathogenesis. Reoviruses infect respiratory and intestinal epithelium and disseminate systemically in newborn animals. Until now, a strategy to rescue infectious virus from cloned cDNA has not been available for any member of the Reoviridae family of dsRNA viruses. We report the generation of viable reovirus following plasmid transfection of murine L929 (L) cells using a strategy free of helper virus and independent of selection. We used the reovirus reverse genetics system to introduce mutations into viral capsid proteins sigma1 and sigma3 and to rescue a virus that expresses a green fluorescent protein (GFP) transgene, thus demonstrating the tractability of this technology. The plasmid-based reverse genetics approach described here can be exploited for studies of reovirus replication and pathogenesis and used to develop reovirus as a vaccine vector.  相似文献   
2.
Microarray-driven gene-expression profiles are generally produced and analyzed for a single specific experimental model. We have assessed an analytical approach that simultaneously evaluates multi-species experimental models within a particular biological condition using orthologous genes as linkers for the various Affymetrix microarray platforms on multi-species models of ventilator-associated lung injury. The results suggest that this approach may be a useful tool in the evaluation of biological processes of interest and selection of process-related candidate genes.  相似文献   
3.
A mid-abdominal mass was discovered during routine physical examination of a rhesus macaque (Macaca mulatta). Further diagnostics and exploratory laparotomy were performed, revealing a fluid-filled cyst attached to the caudal free margin of the greater omentum. Formation and pulsatile movement of white-colored circumferential bands within the wall of the cyst were observed during surgery. The cyst was removed and later was dissected. The discovery of a single invaginated scolex identified the cyst as a cysticercus. The location and characteristics of the cysticercus were consistent with the larval form of Taenia hydatigena.  相似文献   
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5.
The vervet monkey was evaluated as a primate model for use in assisted reproductive technologies (ARTs). Eight adult female vervets were hormonally monitored for their potential use as egg donors and those six females displaying regular menstrual cycles were subjected to controlled ovarian stimulation with recombinant human gonadotropins. Three animals failed to respond while laparoscopic follicular aspiration was performed on the other three females at 27-30 h post-human chorionic gonadotropin administration. A total of 62, 40, and 18 oocytes was recovered from these three animals of which 30, 20, and 4, respectively, matured to the metaphase II stage and were subsequently inseminated using intracytoplasmic sperm injection. An average of 40+/-15% (SEM) of the inseminated oocytes were fertilized based on pronucleus formation and timely cleavage. One embryo from each of the two stimulated females developed into expanded blastocysts. Two adult male vervets were assessed as sperm donors. Neither adjusted well to the restraint and collection procedure required for penile electroejaculation. Samples collected via rectal electroejaculation were very low in sperm motility and concentration; however, cauda epididymal aspirations from one male yielded an adequate concentration of motile sperm. These results emphasize the need to establish species-specific ovarian stimulation protocols and semen collection techniques if vervets are to be considered for basic and applied (ARTs) research on primate gametes or embryos.  相似文献   
6.
Reovirus cell entry is mediated by attachment to cell surface carbohydrate and junctional adhesion molecule A (JAM-A) and internalization by beta1 integrin. The beta1 integrin cytoplasmic tail contains two NPXY motifs, which function in recruitment of adaptor proteins and clathrin for endocytosis and serve as sorting signals for internalized cargo. As reovirus infection requires disassembly in the endocytic compartment, we investigated the role of the beta1 integrin NPXY motifs in reovirus internalization. In comparison to wild-type cells (beta1+/+ cells), reovirus infectivity was significantly reduced in cells expressing mutant beta1 integrin in which the NPXY motifs were altered to NPXF (beta1+/+Y783F/Y795F cells). However, reovirus displayed equivalent binding and internalization levels following adsorption to beta1+/+ cells and beta1+/+Y783F/Y795F cells, suggesting that the NPXY motifs are essential for transport of reovirus within the endocytic pathway. Reovirus entry into beta1+/+ cells was blocked by chlorpromazine, an inhibitor of clathrin-mediated endocytosis, while entry into beta1+/+Y783F/Y795F cells was unaffected. Furthermore, virus was distributed to morphologically distinct endocytic organelles in beta1+/+ and beta1+/+Y783F/Y795F cells, providing further evidence that the beta1 integrin NPXY motifs mediate sorting of reovirus in the endocytic pathway. Thus, NPXY motifs in the beta1 integrin cytoplasmic tail are required for functional reovirus entry, which indicates a key role for these sequences in endocytosis of a pathogenic virus.  相似文献   
7.

Background

Chronic obstructive pulmonary disease (COPD) is characterised by pulmonary and systemic inflammation which flare-up during episodes of acute exacerbation (AECOPD). Given the role of Toll-like receptors (TLRs) in the induction of inflammatory responses we investigated the involvement of TLRs in COPD pathogenesis.

Methods

The expression of TLR-2, TLR-4 and CD14 in monocytes was analyzed by flow cytometry. To study the functional responses of these receptors, monocytes were stimulated with peptidoglycan or lipopolysaccharide and the amounts of TNFα and IL-6 secreted were determined by ELISA.

Results

We found that the expression of TLR-2 was up-regulated in peripheral blood monocytes from COPD patients, either clinically stable or during AECOPD, as compared to never smokers or smokers with normal lung function. Upon stimulation with TLR-2 ligand monocytes from COPD patients secreted increased amounts of cytokines than similarly stimulated monocytes from never smokers and smokers. In contrast, the expressions of TLR-4 and CD14 were not significantly different between groups, and the response to lipopolysaccharide (a TLR-4 ligand) stimulation was not significantly different either. At discharge from hospital TLR-2 expression was down-regulated in peripheral blood monocytes from AECOPD patients. This could be due to the treatment with systemic steroids because, in vitro, steroids down-regulated TLR-2 expression in a dose-dependent manner. Finally, we demonstrated that IL-6, whose plasma levels are elevated in patients, up-regulated in vitro TLR-2 expression in monocytes from never smokers.

Conclusion

Our results reveal abnormalities in TLRs expression in COPD patients and highlight its potential relationship with systemic inflammation in these patients.
  相似文献   
8.
Recreational big game hunters make a significant contribution to conservation through kills of deer, pigs, chamois and tahr. New opportunities for managing recreational hunting through the proposed Game Animal Council underscore the need to understand the implications of potential changes in recreational hunting participation and harvests. Based on a survey of hunters' recall over a year, hunters averaged 15.63 (SEM = 0.58) big game hunts per year, spending 30.53 (SEM = 0.85) days hunting and killing 8.92 (SEM = 0.69) big game animals. Hunters commonly targeted several species on a single hunt, with highly skewed distributions for hunter effort and kills. Mean monthly expenditure on big game hunting items was $296.78 (SEM = $8.95). Results demonstrate that big game hunting is a significant activity in New Zealand, but this varies considerably among hunters with a small number responsible for the vast majority of kills. These are important considerations for future big game hunting management.  相似文献   
9.
Progressive multifocal leukoencephalopathy (PML) is a fatal disease with limited treatment options, both clinically and in the research pipeline. Potential therapies would target and neutralize its etiologic agent, JC polyomavirus (JCPyV). The innate immune response to JCPyV infection has not been studied, and little is known about the initial host response to polyomavirus infection. This study examined the ability of a human alpha defensin, HD5, to neutralize JCPyV infection in human fetal glial cells. We show that HD5, by binding to the virion, blocks infection. The JCPyV-HD5 complexes bind to and enter host cells but are reduced in their ability to reach the endoplasmic reticulum (ER), where virions are normally uncoated. Furthermore, HD5 binding to the virion stabilizes the capsid and prevents genome release. Our results show that HD5 neutralizes JCPyV infection at an early postentry step in the viral life cycle by stabilizing the viral capsid and disrupting JCPyV trafficking. This study provides a naturally occurring platform for developing antivirals to treat PML and also expands on the known capabilities of human defensins.  相似文献   
10.
Leg autotomy and regeneration can have severe impacts on survival and reproduction, and these impacts may be even more pronounced in animals with multifarious legs, such as decapods. Thus, determining the patterns and frequency of autotomy and regeneration could reveal the effects of these processes on the individual and population level. We investigated whether some legs are lost more often than others and if all legs are equally likely to be regenerated. We sampled nearly 500 purple shore crabs (Hemigrapsus nudus) and showed that (1) most animals are found with at least one injured leg, (2) the patterns of autotomy differ between males and females, and (3) successful claw regeneration is unlikely in both males and females. Future work with H. nudus and other grapsid crabs will elucidate how patterns seen here relate to other developmental and ecological factors.  相似文献   
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