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Introduction
Legally mandated segregation policies dictated significant differences in the educational experiences of black and white Americans through the first half of the 20th century, with markedly lower quality in schools attended by black children. We determined whether school term length, a common marker of school quality, was associated with blood pressure and hypertension among a cohort of older Americans who attended school during the de jure segregation era.Methods
National Health and Nutrition Examination Survey I and II data were linked to state level historical information on school term length. We used race and gender-stratified linear regression models adjusted for age, state and year of birth to estimate effects of term length on systolic and diastolic blood pressure (SBP and DBP) and hypertension for US-born adults. We also tested whether correcting years of schooling for term length differences attenuated estimated racial disparities.Results
Among black women, 10% longer school term was associated with lower SBP, DBP and hypertension prevalence (2.1 mmHg, 1.0 mmHg, and 5.0 percentage points respectively). Associations for whites and for black men were not statistically significant. Adjustment for education incorporating corrections for differences in school term length slightly attenuated estimated racial disparities.Conclusions
Longer school term length predicted better BP outcomes among black women, but not black men or whites. 相似文献44.
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Carla B. Marienfeld Daniel B. DiCapua Gordon K. Sze Jonathan M. Goldstein 《The Yale journal of biology and medicine》2010,83(2):67-71
Objective: To show the first clinically reported case of Cat Scratch Disease (CSD) presenting as a focal neurologic deficit in an immunocompetent adult.Patient: 59-year-old male with a history of a previous stroke.Results: Examination showed an expressive aphasia, word substitution errors, and impaired repetition. A head CT and MRI showed no acute changes. The EEG findings were non-focal and did not show any epileptiform activity. The patient had a history of contact with stray kittens and previous axillary lymphadenopathy. Bartonella henselae serology titers were IgG positive 1:1024 (< 64) and IgM positive 1:20 (< 16). After antibiotic administration, the patient’s symptoms and aphasia resolved.Conclusions: Focal presentations concerning for stroke or partial seizure activity may have underlying infectious etiology. We recommend consideration of CSD in the differential diagnosis of any adult with a history of lymphadenopathy, fever, and recent contact with a cat who presents with neurologic complications. 相似文献
47.
Succinic acid production from wheat using a biorefining strategy 总被引:2,自引:0,他引:2
The biosynthesis of succinic acid from wheat flour was investigated in a two-stage bio-process. In the first stage, wheat
flour was converted into a generic microbial feedstock either by fungal fermentation alone or by combining fungal fermentation
for enzyme and fungal bio-mass production with subsequent flour hydrolysis and fungal autolysis. In the second stage, the
generic feedstock was converted into succinic acid by bacterial fermentation by Actinobacillus succinogenes. Direct fermentation of the generic feedstock produced by fungal fermentation alone resulted in a lower succinic acid production,
probably due to the low glucose and nitrogen concentrations in the fungal broth filtrate. In the second feedstock production
strategy, flour hydrolysis conducted by mixing fungal broth filtrate with wheat flour generated a glucose-rich stream, while
the fungal bio-mass was subjected to autolysis for the production of a nutrient-rich stream. The possibility of replacing
a commercial semi-defined medium by these two streams was investigated sequentially. A. succinogenes fermentation using only the wheat-derived feedstock resulted in a succinic acid concentration of almost 16 g l–1 with an overall yield of 0.19 g succinic acid per g wheat flour. These results show that a wheat-based bio-refinery employing
coupled fungal fermentation and subsequent flour hydrolysis and fungal autolysis can lead to a bacterial feedstock for the
efficient production of succinic acid. 相似文献
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Proteins are dynamic molecules that often undergo conformational changes while performing their specific functions, such as target recognition, ligand binding and catalysis. NMR spectroscopy is uniquely suited to study protein dynamics, because site-specific information can be obtained for motions that span a broad range of time scales. The information obtained from NMR dynamics experiments has provided insights into specific structural changes or conformational energetics associated with molecular function. In the last decade, a number of new advancements in NMR methodologies have further extended our ability to characterize protein dynamics. Here, we present an overview of current NMR technology that is used to monitor the dynamic properties of proteins. 相似文献
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A monomeric 5.5-kDa protein with hemolytic activity toward rabbit erythrocytes was isolated from seeds of Albizia lebbeck by using a protocol that involved ion-exchange chromatography on Q-Sepharose and SP-Sepharose, hydrophobic interaction chromatography on Phenyl-Sepharose, and gel filtration on Superdex 75. It was unadsorbed on both Q-Sepharose and SP-Sepharose, but adsorbed on Phenyl-Sepharose. Its hemolytic activity was fully preserved in the pH range 0-14 and in the temperature range 0-100 °C, and unaffected in the presence of a variety of metal ions and carbohydrates. The hemolysin reduced viability of murine splenocytes and inhibited proliferation of MCF-7 breast cancer cells and HepG2 hepatoma cells with an IC50 of 0.21, 0.97, and 1.37 μM, respectively. It impeded mycelial growth in the fungi Rhizoctonia solani with an IC50 of 39 μM but there was no effect on a variety of other filamentous fungi, including Fusarium oxysporum, Helminthosporium maydis, Valsa mali and Mycosphaerella arachidicola. Lebbeckalysin inhibited growth of Escherichia coli with an IC50 of 0.52 μM. 相似文献