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White lines in L-edge x-ray absorption spectra and their implications for anomalous diffraction studies of biological materials. 下载免费PDF全文
R C Lye J C Phillips D Kaplan S Doniach K O Hodgson 《Proceedings of the National Academy of Sciences of the United States of America》1980,77(10):5884-5888
We have measured high-resolution x-ray absorption spectra of lanthanide (Ln) and heavy transition metal complexes that display prominent narrow absorption peaks near the L2 and L3 absorption edges. The anomalous scattering factors (f' and f"), which are mathematically related to the absorption cross section, have correspondingly sharp changes in their magnitude within 5-10 eV of the absorption edge. Calculations of the magnitude of the change in f' and f" demonstrate that significant changes (on the order of 20 electrons in f') can be expected for these materials. These substantial changes in the anomalous scattering factors have applications to deriving structural information for macromolecules from x-ray diffraction studies. The magnitude of the changes indicate that the anomalous scattering technique is a powerful means of obtaining structural characteristics for macromolecules in single crystals, in solution, and in biological membranes. 相似文献
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Gudlavalleti?Venkata?S?MurthyEmail author Neena?John Jayanthi?Sagar South India Disability Evidence Study Group 《BMC women's health》2014,14(1):146
Background
Evidence shows that women with disability have adverse pregnancy outcomes compared to those without a disability. There is a lack of published data on reproductive health of women with disability in India till date. The objective of the South India Disability Evidence (SIDE) Study was to compare reproductive health parameters including pregnancy experience, health access during pregnancy and type of delivery among women with disability compared to women with no disability.Methods
The study was conducted in one district each in two States (Andhra Pradesh and Karnataka) in 2012. A case-control design was used to identify appropriate age and sex-matched controls for women with disability identified through a population-based survey. Trained key informants first listed women with disabilities who were then examined by a medical team to confirm the diagnosis. Trained research investigators administered questionnaire schedules to both groups of women to collect information on reproductive health and outcomes of any pregnancy experienced in the past two years.Results
A total of 247 women with disability and 324 age-matched controls aged 15-45 years were recruited for the study. 87% of the women with disability had a physical disability. The mean age of women with disability was 29.86 against 29.71 years among women without a disability. A significantly lower proportion of women with disability experienced pregnancy (36.8%) compared to women without a disability (X 2 –16.02 P <0.001). The odds ratio for suffering from diabetes among women with disability compared to women without a disability was 19.3(95% CI: 1.2- 313.9), while it was 9.5 (95% CI: 2.2-40.8) for depression. A higher proportion of women without a disability (7.7%) compared to women with a disability (5.3%) reported a successful pregnancy in the past two years. There were no statistically significant differences between women with and without a disability with regard to utilization of antenatal care and pregnancy outcomes.Conclusions
The study provides evidence on some reproductive health parameters of women with disability in India for the first time ever. The findings will help in formulating policy and to develop specific interventions to improve pregnancy outcomes for women with disability in India.26.
Yusof Khairunnisa’ Md Makpol Suzana Fen Lye Siew Jamal Rahman Wan Ngah Wan Zurinah 《Journal of natural medicines》2019,73(4):745-760
Journal of Natural Medicines - Our previous study reported that combined treatment of γ-tocotrienol with 6-gingerol showed promising anticancer effects by synergistically inhibiting... 相似文献
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Maternal Vitamin D Status During Pregnancy and Bone Mass in Offspring at 20 Years of Age: A Prospective Cohort Study 下载免费PDF全文
Kun Zhu Jenny Mountain Stephen Lye Craig Pennell John P Walsh 《Journal of bone and mineral research》2014,29(5):1088-1095
It is uncertain whether the vitamin D status of pregnant women influences bone mass of their children. Cohort studies have yielded conflicting results; none have examined offspring at skeletal maturity. This longitudinal, prospective study investigated the association between maternal vitamin D status and peak bone mass of offspring in 341 mother and offspring pairs in the Western Australian Pregnancy Cohort (Raine) Study. Maternal serum samples collected at 18 weeks gestation were assayed for 25‐hydroxyvitamin D (25OHD). Outcomes were total body bone mineral content (BMC) and bone mineral density (BMD) measured by dual‐energy X‐ray absorptiometry in offspring at 20 years of age. The mean (± SD) maternal serum 25OHD concentration was 57.2 ± 19.2 nmol/L; 132 women (38.7%) were vitamin D‐deficient (25OHD <50 nmol/L). After adjustment for season of sample collection, maternal factors, and offspring factors (sex, birth weight, and age, height, lean mass, and fat mass at 20 years), maternal 25OHD concentration was positively associated with total body BMC and BMD in offspring, with a mean difference of 19.2 (95% confidence interval [CI], 5.6–32.7) g for BMC and 4.6 (95% CI, 0.1–9.1) mg/cm2 for BMD per 10.0 nmol/L of maternal 25OHD. Maternal vitamin D deficiency was associated with 2.7% lower total body BMC (mean ± SE) (2846 ± 20 versus 2924 ± 16 g, p = 0.004) and 1.7% lower total body BMD (1053 ± 7 versus 1071 ± 5 mg/cm2, p = 0.043) in the offspring. We conclude that vitamin D deficiency in pregnant women is associated with lower peak bone mass in their children. This may increase fracture risk in the offspring in later life. © 2014 American Society for Bone and Mineral Research. 相似文献
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Hau Wei Khoo Terrence Chi Hong Hui Salahudeen Mohamed Haja Mohideen Yeong Shyan Lee Charlene Jin Yee Liew Shawn Shi Xian Kok Barnaby Edward Young Sean Wei Xiang Ong Shirin Kalimuddin Seow Yen Tan Jiashen Loh Lai Peng Chan Angeline Choo Choo Poh Steven Bak Siew Wong Yee-Sin Leo David Chien Lye Gregory Jon Leng Kaw Cher Heng Tan 《Singapore medical journal》2021,62(9):458
INTRODUCTIONChest radiographs (CXRs) are widely used for the screening and management of COVID-19. This article describes the radiographic features of COVID-19 based on an initial national cohort of patients.METHODSThis is a retrospective review of swab-positive patients with COVID-19 who were admitted to four different hospitals in Singapore between 22 January and 9 March 2020. Initial and follow-up CXRs were reviewed by three experienced radiologists to identify the predominant pattern and distribution of lung parenchymal abnormalities.RESULTSIn total, 347 CXRs of 96 patients were reviewed. Initial CXRs were abnormal in 41 (42.7%) out of 96 patients. The mean time from onset of symptoms to CXR abnormality was 5.3 ± 4.7 days. The predominant pattern of lung abnormality was ground-glass opacity on initial CXRs (51.2%) and consolidation on follow-up CXRs (51.0%). Multifocal bilateral abnormalities in mixed central and peripheral distribution were observed in 63.4% and 59.2% of abnormal initial and follow-up CXRs, respectively. The lower zones were involved in 90.2% of initial CXRs and 93.9% of follow-up CXRs.CONCLUSIONIn a cohort of swab-positive patients, including those identified from contact tracing, we found a lower incidence of CXR abnormalities than was previously reported. The most common pattern was ground-glass opacity or consolidation, but mixed central and peripheral involvement was more common than peripheral involvement alone. 相似文献
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Bohanna I Georgiou-Karistianis N Sritharan A Asadi H Johnston L Churchyard A Egan G 《Brain imaging and behavior》2011,5(3):171-180
White matter (WM) degeneration is an important feature of Huntington’s disease (HD) neuropathology. To investigate WM degeneration
we used Diffusion Tensor Imaging and Tract-Based Spatial Statistics to compare Fractional Anisotropy, Mean Diffusivity (MD),
parallel diffusivity and perpendicular diffusivity (λ⊥) in WM throughout the whole brain in 17 clinically diagnosed HD patients
and 16 matched controls. Significant WM diffusivity abnormalities were identified primarily in the corpus callosum (CC) and
external/extreme capsules in HD patients compared to controls. Significant correlations were observed between motor symptoms
and MD in the CC body, and between global cognitive impairment and λ⊥ in the CC genu. Probabilistic tractography from these
regions revealed degeneration of functionally relevant interhemispheric WM tracts. Our findings suggest that WM degeneration
within interhemispheric pathways plays an important role in the deterioration of cognitive and motor function in HD patients,
and that improved understanding of WM pathology early in the disease is required. 相似文献
30.
Leah C. Stevenson India Bohanna Jan A. Robertson Alan R. Clough 《Drug and alcohol review》2013,32(6):627-630