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481.
A case of aplasia cutis congenita involving the scalp, cranium, and dura is presented to illustrate the complication of major hemorrhage from the sagittal sinus that may occur if closure is delayed. Subsequent problems with scalp-flap cover eventually required split-skin grafting of the defect. The case for surgery as soon after birth as possible is reinforced. 相似文献
482.
Sonya M. Schuh-Huerta Nicholas A. Johnson Mitchell P. Rosen Barbara Sternfeld Marcelle I. Cedars Renee A. Reijo Pera 《Human genetics》2012,131(11):1709-1724
Oocyte loss has a significant impact on fertility and somatic health. Yet, we know little about factors that impact this process. We sought to identify genetic variants associated with ovarian reserve (oocyte number as measured by antral follicle count, AFC). Based on recently published genome-wide scans that identified loci associated with age of menopause, we also sought to test our hypothesis that follicle number and menopausal age share underlying genetic associations. We analyzed menopause-related variants for association with follicle number in an independent population of approximately 450 reproductive-aged women of European and African ancestry; these women were assessed for AFC, anthropometric, clinical, and lifestyle factors. One SNP strongly associated with later menopausal age in Caucasian women (+1.07?±?0.11?years) in previous work was also associated with higher follicle counts in Caucasians (+2.79?±?1.67 follicles) in our study. This variant is within the Minichromosome Maintenance Complex Component 8 (MCM8) gene, which we found was expressed within oocytes in follicles of the human ovary. In genome-wide scans of AFC, we also identified one marginally genome-wide and several nominally significant SNPs within several other genes associated with follicle number in both ethnic groups. Further, there were overlapping variants associated with multiple ovarian reserve markers (AFC, serum hormone levels, menopausal age). This study provides the first evidence for direct genetic associations underlying both follicle number and menopause and identifies novel candidate genes. Genetic variants associated with ovarian reserve may facilitate discovery of genetic markers to predict reproductive health and lifespan in women. 相似文献
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484.
Sonya Urnowey Toshihiro Ansai Vira Bitko Koji Nakayama Tadamichi Takehara Sailen Barik 《BMC microbiology》2006,6(1):26
Background
Porphyromonas gingivalis is the foremost oral pathogen of adult periodontitis in humans. However, the mechanisms of bacterial invasion and the resultant destruction of the gingival tissue remain largely undefined. 相似文献485.
486.
Female Competition over Core Areas in <Emphasis Type="Italic">Pan troglodytes schweinfurthii</Emphasis>, Kibale National Park,Uganda 总被引:1,自引:1,他引:0
Sonya M. Kahlenberg Melissa Emery Thompson Richard W. Wrangham 《International journal of primatology》2008,29(4):931-947
Aggression is rare among wild female chimpanzees. However, in the Kanyawara chimpanzee community in Kibale National Park,
Uganda, stable use of food-rich core areas is linked to increased reproductive success, suggesting that contest competition
might occur over access to the highest-quality ranges. To examine this hypothesis, we studied aggression and dominance relationships
among Kanyawara females during a 10-yr period that included the immigration of 5 females into the community. We tested 2 predictions:
1) that female-female aggression should intensify when immigrants enter the community because this is when core area access
is determined and 2) that the quality of core areas should reflect relative female dominance relationships. In support of
the first prediction, female-female aggression increased 4-fold when new immigrants were in the community, with rates peaking
when there were multiple immigrants. This pattern was due primarily to aggression by resident mothers toward immigrants and
featured coalitionary aggression, a rare behavior among female chimpanzees. In support of the second prediction, females occupying
core areas high in foraging quality ranked high overall and higher than expected for their ages, whereas females occupying
low-quality core areas were lower-ranking and ranked lower than expected for their ages. Together, the data indicate that
though female aggression does not regularly occur in chimpanzees, contest competition continues to play an important role
in determining long-term access to resources, an important correlate of reproductive success. 相似文献
487.
488.
Ahmed Warish Staley Christopher Kaiser Thomas Sadowsky Michael J. Kozak Sonya Beale David Simpson Stuart 《Applied microbiology and biotechnology》2018,102(16):7159-7170
Applied Microbiology and Biotechnology - Understanding the microbial quality of recreational waters is critical to effectively managing human health risks. In recent years, the development of new... 相似文献
489.
The fear, flight or fight response serves as the fundamental physiological basis for examining an organism''s awareness of its environment under an impending predator attack. Although it is not known whether invertebrates posses an autonomic nervous system identical to that of vertebrates, evidence shows invertebrates have a sympathetic-like response to regulate the internal environment and ready the organism to act behaviorally to a given stimuli. Furthermore, this physiological response can be feasibly measured and it acts as a biological index for the animal''s internal state. Measurements of the physiological response can be directly related to internal and external stressors through changes in the central nervous system controlled coordination of the cardio-vascular and respiratory systems. More specifically, monitoring heart and ventilation rates provide quantifiable measures of the stress response not always behaviorally observed. Crayfish are good model organisms for heart and ventilatory rate measurements due to the feasibility of recording, as well as the rich history known of the morphology of the crayfish, dating back to Huxley in 1888, and the well-studied typical behaviors. 相似文献
490.
Ruthenium(II) bis(2,2″-pyridyl) complexes with bridging ligands: 6,7-dichloro-2,3-di(2-pyridyl)quinoxaline; 2,3-di(2-pyridyl)-quinoxaline; 5-methyl-2,3-di(2-pyridyl) quinoxaline; 6,7-dibenzo-2,3-di(2-pyridyl)quinoxaline have been prepared. The electrochemical and spectroscopic properties of these complexes are reported. The resonance Raman spectroelectrochemical results indicate the presence of oxidation state sensitive marker bands in the resonance Raman spectra of the oxidized complexes. The spectroscopic data for the reduced complexes is similar for all four species. The resonance Raman data for the reduced species are dominated by 2,2″-bipyridyl vibrations. 相似文献