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51.

Background  

Despite the importance of glucocorticoids in suppressing immune and inflammatory responses, their role in enhancing host immune and defense response against invading bacteria is poorly understood. Toll-like receptor 2 (TLR2) has recently gained importance as one of the major host defense receptors. The increased expression of TLR2 in response to bacteria-induced cytokines has been thought to be crucial for the accelerated immune response and resensitization of epithelial cells to invading pathogens.  相似文献   
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In the last decade, treatment for castration-resistant prostate cancer has changed markedly, impacting symptom control and longevity for patients. However, a large proportion of cases progress despite androgen deprivation therapy and chemotherapy, while still being fit enough for several more lines of treatment. Overstimulation of the androgen receptor (AR) activity is the main driver of this cancer. Targeting biological functions of the AR or its co-regulators has proven very effective in this disease and led to the development of several highly effective drugs targeting the AR signalling axis. Drugs such as enzalutamide demonstrated that the improvement in anti-tumour efficacy is closely correlated with an affinity for the AR and its activity and have established the paradigm that AR remains activity in aggressive disease. However, as importantly, key insights into mechanisms of resistance are guiding the development of the next generation of AR-targeted drugs. This review outlines the historical development of these highly specific agents, their mechanism of action in the context of defective AR activity, and explores the potential for the upcoming next-generation AR inhibitors (ARI) for prostate cancer by targeting the alternative domains of AR, rather than by the conventional ligand-binding domain approach. There is huge potential in these approaches to develop new drugs with high clinical activity and further improve the outlook for patients.  相似文献   
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The auditory system in larvae of the migratory locust   总被引:1,自引:0,他引:1  
ABSTRACT. The course and projection areas of the tympanal receptor fibres in the thoracic ventral cord were revealed by iontophoresis in the last three larval instars. There were no significant differences between the arrangement in larvae and that in adults. The threshold curves of the auditory organ of the last three instars were measured by recording summed potentials in the tympanal nerve. In the frequency range tested (1–20 kHz), larvae and adults differed only in sensitivity. More detailed information was obtained by single-cell recordings from receptor neurones in the tympanal nerve of last instar larvae. No differences could be shown between the threshold curves, or the suprathreshold activity, of low frequency receptors of last instars and adults. However, the high frequency receptors of the last instars are far less sensitive in the frequency range above 12 kHz. This seems to depend on the different mechanical properties of the tympanum in larvae. The response patterns of some typical ventralcord neurones (G-, K-, B-type) were identified by extracellular single-cell recordings in last instar larvae. Convergence of auditory and vibratory inputs onto the G-neurone and the B-neurone (as is known to exist in the adult) was found in larvae in the final and penultimate instars to be causing similar response patterns.  相似文献   
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Urolepis rufipes Ashmead, a pteromalid wasp, was recently discovered parasitizing house fly and stable fly pupae in eastern Nebraska dairies. Studies have been conducted on the biology of this parasite to evaluate its potential as a biological control agent of stable flies (Stomoxys calcitrans (L.] and house flies (Musca domestica L.). House fly pupae were suitable as hosts for U.rufipes at all ages; however, significantly higher parasitism occurred on host pupae aged 96-120 h. Parasite-induced mortality (host mortality without progeny production) was higher than for other pteromalid parasites of filth flies under similar conditions. Parasitism increased with parasite--host ratio at 20 degrees C; however, the opposite was noted at 30 degrees C for parasite--host ratios ranging from 5:50 to 50:50. Fly eclosion decreased as parasite--host ratio increased at 20 degrees C, and no host eclosion occurred at the highest parasite--host ratios (20:50 and 50:50) at 30 degrees C. Females produced an average of 18.6 female and 7.6 male progeny. 88% of the progeny were produced during the first 6 days post parental eclosion. The short life span, low progeny emergence rate and high per cent host eclosion, in comparison with other parasite species, suggests that the Nebraska strain of U.rufipes may not an effective biological control agent of house flies.  相似文献   
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