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51.
Analyzed drinking response of 5 male White Carneaux pigeons by means of high-speed cinematography. Like eating, drinking may be subdivided into 3 movement patterns involving the effector systems of the neck, eyelids, and beak. The major topographic difference between the 2 responses involves beak opening (gape). In eating, beak opening begins prior to contact with the food, and the amount of gape is directly proportional to seed size. In drinking, the beak remains almost closed during descent and opens intermittently and with a relatively small gape during water intake. The topography of drinking in the pigeon differs from that of many birds, and these differences reflect a difference in the mechanism of water ingestion. Data in this study confirm previous observations of a general resemblance between certain features of the pigeon's drinking behavior and the topography of water-reinforced key pecks. (9 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
52.
Maternal obesity predisposes for hepato-metabolic disorders early in life. However, the underlying mechanisms causing early onset dysfunction of the liver and metabolism remain elusive. Since obesity is associated with subacute chronic inflammation and accelerated aging, we test the hypothesis whether maternal obesity induces aging processes in the developing liver and determines thereby hepatic growth. To this end, maternal obesity was induced with high-fat diet (HFD) in C57BL/6N mice and male offspring were studied at the end of the lactation [postnatal day 21 (P21)]. Maternal obesity induced an obese body composition with metabolic inflammation and a marked hepatic growth restriction in the male offspring at P21. Proteomic and molecular analyses revealed three interrelated mechanisms that might account for the impaired hepatic growth pattern, indicating prematurely induced aging processes: (1) Increased DNA damage response (γH2AX), (2) significant upregulation of hepatocellular senescence markers (Cdnk1a, Cdkn2a); and (3) inhibition of hepatic insulin/insulin-like growth factor (IGF)-1-AKT-p38-FoxO1 signaling with an insufficient proliferative growth response. In conclusion, our murine data demonstrate that perinatal obesity induces an obese body composition in male offspring with hepatic growth restriction through a possible premature hepatic aging that is indicated by a pathologic sequence of inflammation, DNA damage, senescence, and signs of a possibly insufficient regenerative capacity.  相似文献   
53.
Patients with advanced thyroid cancer harboring NTRK rearrangements can be treated with highly effective selective inhibitors. Immunohistochemistry (IHC) analysis, to detect Trk protein expression, represents an appealing screening strategy for NTRK rearrangements, but its efficacy has been poorly explored in thyroid cancer. The aim of this study is to investigate the diagnostic utility of Trk IHC in the identification of NTRK rearrangements. A series of 26 follicular-derived thyroid tumors, positive for NTRK rearrangements, and 28 NTRK fusion-negative controls were retrospectively analyzed by IHC using the pan-Trk monoclonal antibody (clone EPR17341) on the Ventana system. Area under the curve (AUC), sensitivity and specificity were calculated by ROC analysis. Trk expression was detected in 25 samples, including 22 out of the 26 NTRK-rearranged (84.6%) and three out of 28 NTRK-negative samples (10.7%). Four out of twenty-six NTRK-rearranged thyroid tumors were negative for Trk expression (15.4%), all carrying the ETV6/NTRK3 fusion. The AUC, sensitivity and specificity were 0.87, 0.85 and 0.89, respectively. A screening based on IHC analysis showed limited sensitivity and specificity in the identification of NTRK-rearranged tumors. Since falsely negative results could preclude the administration of effective targeted drugs, alternative detection strategies should be considered for thyroid cancer.  相似文献   
54.
It has been accepted for decades that T lymphocytes and metastasising tumour cells traverse basement membranes (BM) by deploying a battery of degradative enzymes, particularly proteases. However, since many redundant proteases can solubilise BM it has been difficult to prove that proteases aid cell migration, particularly in vivo. Recent studies also suggest that other mechanisms allow BM passage of cells. To resolve this issue we exploited heparanase-1 (HPSE-1), the only endoglycosidase in mammals that digests heparan sulfate (HS), a major constituent of BM. Initially we examined the effect of HPSE-1 deficiency on a well-characterised adoptive transfer model of T-cell-mediated inflammation. We found that total elimination of HPSE-1 from this system resulted in a drastic reduction in tissue injury and loss of target HS. Subsequent studies showed that the source of HPSE-1 in the transferred T cells was predominantly activated CD4+ T cells. Based on bone marrow chimeras, two cellular sources of HPSE-1 were identified in T cell recipients, one being haematopoiesis dependent and the other radiation resistant. Collectively our findings unequivocally demonstrate that an acute T-cell-initiated inflammatory response is HPSE-1 dependent and is reliant on HPSE-1 from at least three different cell types.  相似文献   
55.
It is easy to give a list of cognitive processes. They are things like learning, memory, concept formation, reasoning, maybe emotion, and so on. It is not easy to say, of these things that are called cognitive, what makes them so? Knowing the answer is one very important reason to be interested in the mark of the cognitive. In this paper, consider some answers that we think do not work and then offer one of our own which ties cognition to actions explained via the having of reasons.  相似文献   
56.
57.
Longitudinal data from a national sample of Germans (N = 20,434) were used to evaluate stability and change in the Big Five personality traits. Participants completed a brief measure of personality twice, 4 years apart. Structural equation modeling techniques were used to establish measurement invariance over time and across age groups. Substantive questions about differential (or rank-order) and mean-level stability and change were then evaluated. Results showed that differential stability was relatively strong among all age groups but that it increased among young adults, peaked in later life, and then declined among the oldest old. Patterns of mean-level change showed that Extraversion and Openness declined over the life span, whereas Agreeableness increased. Mean levels of Conscientiousness increased among young adults and then decreased among older adults. Trajectories for Neuroticism were relatively flat, with slight increases during middle age and a slight decline in late life. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   
58.
Objective: Marital discord has been linked to both depression and anxiety; however, our understanding of how marriage contributes to the development of internalizing symptoms is limited in scope and lacking specificity. First, it is unclear whether the marital relationship contributes to the broad dimension of internalizing symptoms as opposed to specific diagnoses. Second, it is unclear how the marital relationship contributes to internalizing symptoms: through global marital dissatisfaction or through specific relationship processes (and which processes). The purpose of the present study was to address these 2 issues and, more generally, to develop a comprehensive and refined framework within which to understand the role of marriage in the developmental course of internalizing symptoms. Method: Questionnaire and interview data were collected from 102 husbands and wives 5 times over the first 7 years of marriage. Results: Results indicated that marital discord during the transition into marriage was associated with the broad dimension of internalizing symptoms for husbands but not for wives. Further, both global marital dissatisfaction and an imbalance of power and control put husbands at significant risk for symptoms over the first 7 years of marriage, whereas low levels of emotional intimacy put wives at significant risk. Conclusions: Results exemplify the need to routinely consider intimate relationship processes in etiological models of depression and anxiety and to identify specific clinical targets that can be prioritized in interventions aimed at preventing internalizing disorders. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   
59.
We report on morphosynthesis techniques that have been employed to tune polyamine film nanoarchitectures and on their resulting morphologies. Specific layers discussed include films of aniline/Laponite clay and aniline solution processed with V2O5 catalyst. Synthesis approaches examined include films generated in-situ (glass templating), solution based drop casting, and mechanochemical grinding. Surface topography results suggest that these approaches provide dimensionality control of the polyaniline morphology. Surface images of the mechanochemically ground polyaniline/Laponite nanocomposite layer reveal interfacial contact which is promising for potential heterojunction solar cell designs.  相似文献   
60.
Indoor residual spray (IRS) of insecticides and insecticide-treated bednets (ITNs) are the two most important malaria vector control tools in the tropical world. Application of both tools in the same locations is being implemented for malaria control in endemic and epidemic Africa. The two tools are assumed to have synergistic benefits in reducing malaria transmission because they both act at multiple stages of the transmission cycle. However, this assumption has not been rigorously examined, empirically or theoretically. Using mathematical modelling, we obtained the conditions for which a combination strategy can be expected to improve upon single control tools. Specifically, spraying of dichlorodiphenyltrichloroethane (DDT) in all houses where residents are not using ITNs can reduce transmission of malaria (R0) by up to 10 times more than the reduction achieved through ITNs alone. Importantly, however, we also show how antagonism between control tools can arise via interference of their modes of action. Repellent IRS reduces the likelihood that ITNs are contacted within sprayed houses and ITNs reduce the rate at which blood-fed mosquitoes rest on sprayed walls. For example, 80 per cent coverage of ITNs and DDT used together at the household level resulted in an R0 of 11.1 when compared with an R0 of 0.1 achieved with 80 per cent ITN coverage without DDT. While this undesired effect can be avoided using low-repellence pyrethroid chemicals for IRS, the extent of the potential benefits is also attenuated. We discuss the impact that this result will likely have on future efforts in malaria control combination strategy.  相似文献   
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