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The impulsive activity of parietal cortex neurons of rabbits during the elaboration and specialisation of switching-over of alimentary and defensive conditioned reflexes has been studied. There are changes of parietal cortex neurons activity correlated with the stages of switching-over elaboration. The significant differences of the background neurons activity and neurons response to the conditional signal during alimentary and defensive conditioned reflexes have been established. The dominant motivation influences the neurons activity by modulation of background and conditioned activity of neurons. The integrative properties of neurons investigated in switching-over situation are revealed in their ability to summarize the excitation coming to the same sensory input with excitation from different motivational and reinforcement systems.  相似文献   
53.

Background  

The controlled beating of cilia of the fallopian tube plays an important role in facilitating the meeting of gametes and subsequently transporting the fertilized egg to its implantation site. Rapid effects of progesterone on ciliary beat frequency have been reported in the fallopian tubes of cows, but the identity of the receptors mediating this non-genomic action of progesterone is not known. We recently identified a member of the non-genomic membrane progesterone receptor family, mPR gamma, as a candidate for mediating these actions of progesterone. Here, we investigated the possible presence of a related receptor, mPR beta, in the fallopian tubes of mice and women as well as the possible hormonal regulation of mPR beta and gamma.  相似文献   
54.

Background  

SSWAP (Simple Semantic Web Architecture and Protocol; pronounced "swap") is an architecture, protocol, and platform for using reasoning to semantically integrate heterogeneous disparate data and services on the web. SSWAP was developed as a hybrid semantic web services technology to overcome limitations found in both pure web service technologies and pure semantic web technologies.  相似文献   
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The effect of the constant illumination on the development of spontaneous tumors in female 129/Sv mice was investigated. Forty-six female 129/Sv mice starting from the age of 2 mo were kept under standard light/dark regimen [12 h light (70 lx):12hr dark; LD, control group], and 46 of 129/Sv mice were kept under constant illumination (24 h a day, 2,500 lx, LL) from the age of 5 mo until to natural death. The exposure to the LL regimen significantly accelerated body weight gain, increased body temperature as well as acceleration of age-related disturbances in estrous function, followed by significant acceleration of the development of the spontaneous uterine tumors in female 129/Sv mice. Total tumor incidence as well as a total number of total or malignant tumors was similar in LL and LD group (p > 0.05). The mice from the LL groups survived less than those from the LD group (χ2 = 8.5; p = 0.00351, log-rank test). According to the estimated parameters of the Cox’s regression model, constant light regimen increased the relative risk of death in female mice compared with the control (LD) group (p = 0.0041). The data demonstrate in the first time that the exposure to constant illumination was followed by the acceleration of aging and spontaneous uterine tumorigenesis in female 129/Sv mice.  相似文献   
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The optimum operating temperature and pH have been determined for a catalyst prepared by the insolubilization of a hepatic microsomal mixed-function oxidase on glass beads. Temperature is a more significant variable than pH in determining potential catalyst yield (total product/unit catalyst). An operating range of about 25–28°C is optimal with respect to catalyst life at pH 7.6. Like the purified soluble oxidase, the glass bead-mounted enzyme catalyzes the NADPH- and oxygen-dependent oxidation of a variety of amines, hydrazines, and thioureylenes. The catalyst has been used in a simple slurry reactor to prepare mg quantities of N-oxide metabolites of prochlorperazine, guanethidine, and ethylmorphine.  相似文献   
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There is increasing evidence that a number of cytokines and their receptors are involved in the processes that lead to the development and maintenance of neuropathic pain states. Here we demonstrate that levels of CX3CR1 (the receptor for the chemokine fractalkine) mRNA in lumbar dorsal root ganglia (DRG) increase 5.8-fold 7 days after sciatic nerve axotomy, and 1.7- and 2.9-fold, 3 and 7 days respectively, after the spared nerve injury (SNI) model of neuropathic pain. In contrast, no significant change in the levels of fractalkine mRNA is apparent in the DRG after axotomy or SNI. The increase in CX3CR1 mRNA is paralleled by a 3.9- and 2.1-fold increase in the number of CX3CR1-positive macrophages in the DRG 7 days after axotomy and SNI, respectively. Expression of CX3CR1 in macrophages is also markedly increased in the sciatic nerve proximal to site of injury, by 25.7-fold after axotomy and 16.2-fold after SNI, 7 days after injury. Intra-neural injection into the sciatic nerve of 400 ng or 100 ng of fractalkine in adult 129OlaHsd mice significantly delayed the development of allodynia for 3 days following SNI. Further, CX3CR1 knockout (KO) mice display an increase in allodynia for three weeks after SNI compared to strain-matched Balb/c controls. Taken together, these results suggest an anti-allodynic role for fractalkine and its receptor in the mouse.  相似文献   
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