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91.
The metabolism of cancer cells differs substantially from normal cells, including ion transport. Although this phenomenon has been long recognized, ion transporters have not been viewed as suitable therapeutic targets. However, the acidic pH values present in tumours which are well outside of normal limits are now becoming recognized as an important therapeutic target. Carbonic anhydrase IX (CAIX) is fundamental to tumour pH regulation. CAIX is commonly expressed in cancer, but lowly expressed in normal tissues and that presents an attractive target. Here, we discuss the possibilities of exploiting the acidic, hypoxic tumour environment as possible target for therapy. Additionally, clinical experience with CAIX targeting in cancer patients is discussed.  相似文献   
92.
Recognition memory and anxiety were examined in nulliparous (NP: 0 litters) and multiparous (MP: 5-6 litters) middle-aged female rats (12 months old) to assess possible enduring effects of multiparity at least 3 months after the last litter was weaned. MP females performed significantly better than NP females on the non-spatial memory task, object recognition, and the spatial memory task, object placement. Anxiety as measured on the elevated plus maze did not differ between groups. Monoaminergic activity and levels were measured in prefrontal cortex, CA1 hippocampus, CA3 hippocampus, and olfactory bulb (OB). NP and MP females differed in monoamine concentrations in the OB only, with MP females having significantly greater concentrations of dopamine and metabolite DOPAC, norepinephrine and metabolite MHPG, and the serotonin metabolite 5-HIAA, as compared to NP females. These results indicate a long-term change in OB neurochemistry as a result of multiparity. Brain-derived neurotrophic factor (BDNF) was also measured in hippocampus (CA1, CA3, dentate gyrus) and septum. MP females had higher BDNF levels in both CA1 and septum; as these regions are implicated in memory performance, elevated BDNF may underlie the observed memory task differences. Thus, MP females (experiencing multiple bouts of pregnancy, birth, and pup rearing during the first year of life) displayed enhanced memory task performance but equal anxiety responses, as compared to NP females. These results are consistent with previous studies showing long-term changes in behavioral function in MP, as compared to NP, rats and suggest that alterations in monoamines and a neurotrophin, BDNF, may contribute to the observed behavioral changes.  相似文献   
93.
Humans spend a considerable portion of their lives engaged in ‘stimulus-independent thoughts'' (SIT), or mental activity that occurs independently of input from the immediate external environment. Although such SITs are, by definition, different from thoughts that are driven by stimuli in one''s external environment (i.e. stimulus-dependent thoughts; SDTs), at times, the phenomenology of these two types of thought appears to be deceptively similar. But how similar are they? We address this question by comparing the content of two types of SIT (dreaming and waking SITs) with the content of SDTs. In this 7 day, smartphone-based experience-sampling procedure, participants were intermittently probed during the day and night to indicate whether their current thoughts were stimulus dependent or stimulus independent. They then responded to content-based items indexing the qualitative aspects of their experience (e.g. My thoughts were jumping from topic to topic). Results indicate substantial distinctiveness between these three types of thought: significant differences between at least two of the three mental states were found across every measured variable. Implications are discussed.This article is part of the theme issue ‘Offline perception: voluntary and spontaneous perceptual experiences without matching external stimulation’.  相似文献   
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95.
Human–dog interaction relies to a large extent on nonverbal communication, and it is therefore plausible that human sensitivity to nonverbal signals affects interactions between human and dog. Experience with dogs is also likely to influence human–dog interactions, and it has been suggested that it influences human social skills. The present study investigated possible links between human nonverbal sensitivity, experience with dogs, and the quality of human–dog interactions. Two studies are reported. In study 1, 97 veterinary students took a psychometric test assessing human nonverbal sensitivity and answered a questionnaire on their experience with dogs. The data obtained were then used to investigate the relationship between experience with dogs and sensitivity to human nonverbal communication. The results did not indicate that experience with dogs improves human nonverbal sensitivity. In study 2, 16 students with high, and 15 students with low, levels of human nonverbal sensitivity were selected. Each of the 31 students interacted once with an unknown dog in a greeting situation, and these human–dog interactions were videoed. We found that a combined score of dog behaviors relating to insecurity was associated with the students' level of nonverbal sensitivity and experience with dogs: the dog showed more of the insecure behavior when interacting with students with a low level of nonverbal sensitivity and no experience with dogs than it did when interacting with students with a high level of nonverbal sensitivity (irrespective of experience with dogs).  相似文献   
96.
《Current biology : CB》2022,32(5):1026-1037.e4
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97.
Male apple maggot flies spend considerable time residing on individual host fruit as territories on which they force-copulate arriving females in search of oviposition sites. Here, we present evidence from investigations in nature and the laboratory that shows the propensity of males to reside on a hawthorn or apple fruit as a territory is significantly modifiable through prior experience with fruit and, hence, involves learning. Previous studies revealed that after a female apple maggot fly, Rhagoletis pomonella, arrived on a host hawthorn or apple fruit, its propensity to accept or reject that fruit for egg-laying was similarly modifiable through prior fruit-exposure experience and also involved learning. We discuss how host fruit learning in males and females, in concert with genetic-based differences in host fruit residence and acceptance behavior between populations of flies originating from hawthorn and apple, could give rise to a reduction in gene flow between populations of flies on these two host types.  相似文献   
98.
99.
ABSTRACT The potential advantages of repeated breeding at a particular location should improve reproductive performance in long‐lived species of birds. However, for short‐lived species, natural selection should favor individuals that most quickly develop competency in reproduction. Therefore, we hypothesized that local breeding experience beyond the first breeding attempt at a particular location would have little effect on subsequent reproductive performance of Tree Swallows (Tachycineta bicolor), a species where about 50% of adults breed only once in their lives. We tested this hypothesis using data collected from Tree Swallows in Michigan from 1993 to 2002. Because we were specifically interested in examining the effects of local breeding experience on reproductive performance, we restricted our analyses to after‐second‐year (ASY) females and their mates that we first encountered as breeders. Consistent with our hypothesis, we found no relationship between repeated local breeding experience and the reproductive performance of ASY female Tree Swallows and their mates as measured by clutch size and number of fledged young. However, pairs with more combined total local experience tended to lay eggs earlier in the season. These results suggest that Tree Swallows may benefit from breeding site fidelity, not because repeated local experience improves reproductive performance as measured by the production of fledglings, but because returning individuals acquire nest cavities earlier and are able to begin breeding earlier, providing time to renest in case of early nest failure.  相似文献   
100.
生态型城市公园是城市居民重要的游憩空间,其声景品质直接影响游客体验的满意程度。以福州金山公园为研究对象,通过定性与定量相结合的方法研究生态型城市公园中声景感知与游憩体验之间的关系及其影响因素。研究发现:生态型城市公园中人们更偏爱自然声,尤其是鸟叫声;交通声是主要影响公园景观美景度的声源类型;儿童嬉闹声及音乐声是影响声景安静度的显著因素,交通声、音乐声以及脚步声与总体满意度关系最为密切;年龄、性别和教育背景是社会、人口及行为学因素中影响典型声源感知最显著的3个因素,而不同游览动机的人群对声景感知也存在显著差异。研究结论可为生态型城市公园景观及声景设计提供理论依据。  相似文献   
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