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Maraglas-embedded sections of periodontal membranes around continually growing incisors of Sprague-Dawley rats fixed consecutively in cold glutaraldehyde and Palade's 1 % buffered osmium tetroxide were examined under the electron microscope for oxytalan connective tissue fibers. Oxytalan fibers were noted to consist of bundles of filaments approximately 150 A in diameter with an interfilamentous amorphous substance of approximately the same diameter. A periodicity of fibrillar elements was not obvious. 相似文献
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Wei Wang Amy K. Erbe Mikayla Gallenberger KyungMann Kim Lakeesha Carmichael Dustin Hess Eneida A. Mendonca Yiqiang Song Jacquelyn A. Hank Su-Chun Cheng Sabina Signoretti Michael Atkins Alexander Carlson Jonathan M. Weiss James Mier David Panka David F. McDermott Paul M. Sondel 《Cancer immunology, immunotherapy : CII》2016,65(12):1523-1532
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Carmichael SL Ma C Rasmussen SA Honein MA Lammer EJ Shaw GM;National Birth Defects Prevention Study 《Birth defects research. Part A, Clinical and molecular teratology》2008,82(2):78-85
BACKGROUND: Several previous studies suggested increased risk of craniosynostosis among infants born to women who smoked. METHODS: This study used data from the National Birth Defects Prevention Study, a multi‐state, population‐based case‐control study of infants delivered from 1997–2003. Nonmalformed, liveborn controls were selected randomly from birth certificates or birth hospitals. Data from maternal telephone interviews were available for 531 cases and 5008 controls. RESULTS: Smoking during the first month of pregnancy was not associated with craniosynostosis. Smoking later in pregnancy was associated with increased risk, but only among mothers who smoked at least one pack/day. For example, during the second trimester, the odds ratio for smoking <5 cigarettes/day was 1.0 (95% confidence interval [CI] 0.6, 1.8), but the odds ratio (OR) for smoking 15 or more cigarettes/day was 1.6 (95% CI 0.9, 2.8), after adjustment for maternal age, education, race‐ethnicity, sub‐fertility, parity, folic acid supplement intake, body mass index, and study center. Among women who did not smoke, adjusted odds ratios suggested that secondhand smoke exposure at home, but not at work/school, was associated with modestly increased risk; the OR for home exposure was 1.3 (95% CI 0.9, 1.9). Results followed a similar pattern for some, but not all, specific suture types, but numbers for some groupings were small. CONCLUSIONS: The results suggest moderately increased risk of craniosynostosis among mothers who were the heaviest smokers and who continued to smoke after the first trimester. Results are somewhat equivocal, given that most confidence intervals included one. Birth Defects Research (Part A), 2008. © 2007 Wiley‐Liss, Inc. 相似文献
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Yang W Shaw GM Carmichael SL Rasmussen SA Waller DK Pober BR Anderka M;National Birth Defects Prevention Study 《Birth defects research. Part A, Clinical and molecular teratology》2008,82(3):131-138
BACKGROUND: Congenital diaphragmatic hernia (CDH) is a severe birth defect where there is an opening in the diaphragm through which a portion of the abdominal contents protrudes into the thoracic cavity. The etiologies of CDH remain unknown, although experimental animal data suggest dietary factors might play a role. This study examined whether maternal nutrient intakes were associated with delivering infants with CDH. METHODS: We analyzed infants with isolated CDH who were born from 1997 to 2003 and recruited into the National Birth Defects Prevention Study (NBDPS), a multisite, population‐based case‐control study. Exposure data were obtained from telephone interviews, which were completed within 24 months after delivery, and were available for 377 case mothers and 5,008 control mothers. A food frequency questionnaire was used to derive nutrient intakes during the year before pregnancy. RESULTS: A crude OR of 0.6 (95% CI: 0.3–1.0) was observed for higher intake of choline. Elevated ORs (1.4 to 1.7) were found for lower intakes of choline, cysteine, methionine, and protein. Among women who took vitamin supplements, higher intakes of B vitamins (i.e., folate, vitamin B1, B2, B6, and B12), minerals (i.e., calcium, iron, magnesium, and zinc), and vitamin E were inversely associated with CDH (ORs from 0.7–0.3). Moreover, among women who did not take vitamin supplements, lower intakes of calcium, retinol, selenium, vitamin B12, and vitamin E had positive associations with CDH (ORs from 1.4 to 2.1). CONCLUSIONS: Our observations contribute to a limited body of evidence suggesting a woman's periconceptional diet might be associated with CDH in her offspring. Birth Defects Research (Part A), 2008. © 2007 Wiley‐Liss, Inc. 相似文献
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Erick S. Van Dyke Dennis L. Scarnecchia Brian C. Jonasson Richard W. Carmichael 《Hydrobiologia》2009,625(1):27-42
Winter concealment habitat quality was assessed and its use by juvenile spring Chinook salmon (Oncorhynchus tshawytscha) quantified in three hatching areas of the Grande Ronde River Basin, Oregon USA. Fish densities were significantly higher
in pools with a higher winter concealment habitat index than pools with a lower index. The mean fork length and mean growth
rate of fish did not differ between pools with a higher or lower winter concealment habitat index, even though residual fish
were significantly larger than fish that emigrated. Biomass–density was significantly higher in pools with a higher winter
concealment habitat index than pools with a lower index in all three hatching areas. Biomass–density was positively associated
with the amount of cobble substrate (10–24.9 cm/m2) in all three hatching areas, and inversely associated with embeddedness in two of the hatching areas. Results of this study
indicate that enhancing winter concealment habitat could improve habitat quality resulting in increased carrying capacity
and winter usage by juvenile spring Chinook salmon.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.
Handling editor: J. A. Cambray 相似文献
79.
Background
Many high-throughput genomic experiments, such as Synthetic Genetic Array and yeast two-hybrid, use colony growth on solid media as a screen metric. These experiments routinely generate over 100,000 data points, making data analysis a time consuming and painstaking process. Here we describe ScreenMill, a new software suite that automates image analysis and simplifies data review and analysis for high-throughput biological experiments. 相似文献80.