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951.
952.
The purple martin is a large North American swallow that suffered a severe population crash in the 20th century due to nesting competition from invasive species. We screened an enriched DNA library for microsatellites from purple martins (Progne subis subis). Ten loci consistently amplified and were polymorphic with an allele range of 2–19 and observed heterozygosity ranged from 0.31 to 0.93. Two loci are sex-linked, and two additional loci failed to meet Hardy–Weinberg expectations likely due to the presence of null alleles. These polymorphic microsatellite loci can be used for studies of genetic diversity, population structure, and relatedness, all of which have been suggested to determine the impact of substantial regional declines in population density.  相似文献   
953.
954.
Debate surrounds the role of the limbic system structures’ contribution to spatial orientation. The results from previous studies have supported a role for the mammillary bodies and their projections to the anterior thalamus in rapid encoding of relationships among environmental cues; however, this work is based on behavioral tasks in which environmental and self‐movement cues could not be dissociated. The present study examines the effects of mammillothalamic tract lesions on spatial orientation in the food hoarding paradigm and the water maze. Although the food hoarding paradigm dissociates the use of environmental and self‐movement cues, both sources of information are available to guide performance in the water maze. Mammillothalamic tract lesions selectively impaired performance on both tasks. These impairments are interpreted as providing further evidence for the role of limbic system structures in processing self‐movement cues.  相似文献   
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956.
Abstract –  Objective: The aim of this paper was to report trends in traumatic dental injuries (TDI) in preschool children in Brazil between 2002 and 2006, and assess whether gender, family structure, and socio-economic differences in TDI are significant, and confirm the relationship between TDI and anatomic predisposing factors such as overjet and lip coverage.
Methods:  Three cross-sectional surveys were conducted in 2002, 2004 and 2006 in Diadema using the same protocol. It was estimated that a minimum sample size of 778 5–59 months old children was required to achieve a level of precision with a standard error of <2% Participants were systematically selected from all children attending the National Day of Children's Vaccination carried out in the city of Diadema. The criteria used to assess TDIs were a modified version of Ellis' classification.
Results :  There was a significant increase in TDIs between 2002 and 2006 (47.9%, P  = 0.002). The prevalence of TDIs was 9.4% (95% CI 7.63, 11.42) in 2002, 12.9% (95% CI 11.06, 14.96) in 2004, and 13.9% (95% CI 12.03, 15.84) in 2006 in 5–59 months old children and the treatment of TDI was seriously neglected. There was no significant gender, family structure, and socio-economic differences in the prevalence of TDIs. The relationship between TDI and anatomic predisposing factors such as overjet, lip coverage, and anterior overbite was highly statistically significant ( P  < 0.01).
Conclusion :  The prevalence of TDIs in preschool children in Diadema increased between 2002 and 2006, the treatment of TDIs was neglected, thus it is crucial to generate considerable efforts to implement health promotion strategies to reverse the observed trends and to provide treatment to TDIs to prevent their biologic and psychologic consequences.  相似文献   
957.
958.
We report a 12‐year‐old female presenting with an abdominal tumor. Diagnostic workup revealed giant bilateral ovarian cysts, severe hypothyroidism as well as an elevation of CA 125. We refrained from ovariectomy, which would be necessary for a malignant tumor, in view of an evident Van Wyk and Grumbach syndrome. The patient promptly responded to L ‐thyroxine with complete regression of all symptoms. Hypothyroidism should be considered in the evaluation of ovarian cysts. Although the Van Wyk and Grumbach syndrome is rare, it is crucial to rule it out in order to avoid unnecessary ovarian surgery when thyroid replacement is completely sufficient. Pediatr Blood Cancer 2009;52:677–679. © 2009 Wiley‐Liss, Inc.  相似文献   
959.
We know a great deal about the cellular response to starvation via AMPK, but less is known about the reaction to nutrient excess. Insulin resistance may be an appropriate response to nutrient excess, but the cellular sensors that link these parameters remain poorly defined. In the present study we provide evidence that mitochondrial superoxide production is a common feature of many different models of insulin resistance in adipocytes, myotubes, and mice. In particular, insulin resistance was rapidly reversible upon exposure to agents that act as mitochondrial uncouplers, ETC inhibitors, or mitochondrial superoxide dismutase (MnSOD) mimetics. Similar effects were observed with overexpression of mitochondrial MnSOD. Furthermore, acute induction of mitochondrial superoxide production using the complex III antagonist antimycin A caused rapid attenuation of insulin action independently of changes in the canonical PI3K/Akt pathway. These results were validated in vivo in that MnSOD transgenic mice were partially protected against HFD induced insulin resistance and MnSOD+/− mice were glucose intolerant on a standard chow diet. These data place mitochondrial superoxide at the nexus between intracellular metabolism and the control of insulin action potentially defining this as a metabolic sensor of energy excess.  相似文献   
960.
Ultraviolet B (UVB)-pretreated SKH-1 mice were treated with water, caffeine (0.1 mg/ml), voluntary running wheel exercise (RW) or caffeine together with RW for 14 wk. Treatment of the mice with caffeine, RW, or caffeine plus RW decreased skin tumors per mouse by 27%, 35%, and 62%, respectively, and the tumor volume per mouse was decreased by 61%, 70%, and 85%, respectively. In mechanistic studies, mice were treated with water, caffeine, RW, or caffeine plus RW for 2 wk prior to a single irradiation with UVB. Caffeine plus RW increased RW activity by 22% when compared with RW alone. Caffeine ingestion was not significantly different between groups. Treatment of mice with caffeine plus RW for 2 wk decreased the weight of the parametrial fat pads and stimulated the formation of UVB-induced apoptosis to a greater extent than treatment with caffeine or RW alone. An antibody array revealed that caffeine plus RW administered to mice fed a high-fat diet and irradiated with UVB decreased the epidermal levels of lipopolysaccharide-induced CXC chemokine, soluble TNF alpha receptor-1, and macrophage inflammatory protein-1γ. Overall, caffeine during RW exerts a stronger effect than either treatment alone for decreasing tissue fat, increasing UVB-induced apoptosis, lowering the levels of cytokines associated with inflammation and for inhibiting UVB-induced carcinogenesis.  相似文献   
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