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131.
Philip Anglewicz Dana Sarnak Alison Gemmill Stan Becker 《Studies in family planning》2023,54(1):17-38
Although the reproductive calendar is the primary tool for measuring contraceptive dynamics in low-income settings, the reliability of calendar data has seldom been evaluated, primarily due to the lack of longitudinal panel data. In this research, we evaluated the reproductive calendar using data from the Performance Monitoring for Action Project. We used population-based longitudinal data from nine settings in seven countries: Burkina Faso, Nigeria (Kano and Lagos States), Democratic Republic of Congo (Kinshasa and Kongo Central Provinces), Kenya, Uganda, Cote d'Ivoire, and India. To evaluate reliability, we compared the baseline cross-sectional report of contraceptive use (overall and by contraceptive method), nonuse, or pregnancy with the retrospective reproductive calendar entry for the corresponding month, measured at follow-up. We use multivariable regressions to identify characteristics associated with reliability or reporting. Overall, we find that the reliability of the calendar is in the “moderate/substantial” range for nearly all geographies and tests (Kappa statistics between 0.58 and 0.81). Measures of the complexity of the calendar (number of contraceptive use episodes, using the long-acting method at baseline) are associated with reliability. We also find that women who were using contraception without their partners/husband's knowledge (i.e., covertly) were less likely to report reliably in several countries. 相似文献
132.
Erika J. Wolf Ci-Di Chen Xiang Zhao Zhenwei Zhou Filomene G. Morrison Nikolaos P. Daskalakis Annjanette Stone Steven Schichman Jaclyn Garza Grenier Dana Fein-Schaffer Bertrand R. Huber Traumatic Stress Brain Research Group Carmela R. Abraham Mark W. Miller Mark W. Logue 《Neuropsychopharmacology》2021,46(4):721
133.
Elizabeth A. Maher Isaac Marin‐Valencia Robert M. Bachoo Tomoyuki Mashimo Jack Raisanen Kimmo J. Hatanpaa Ashish Jindal F. Mark Jeffrey Changho Choi Christopher Madden Dana Mathews Juan M. Pascual Bruce E. Mickey Craig R. Malloy Ralph J. DeBerardinis 《NMR in biomedicine》2012,25(11):1234-1244
Glioblastomas and brain metastases demonstrate avid uptake of 2‐[18F]fluoro‐2‐deoxyglucose by positron emission tomography and display perturbations of intracellular metabolite pools by 1H MRS. These observations suggest that metabolic reprogramming contributes to brain tumor growth in vivo. The Warburg effect, excess metabolism of glucose to lactate in the presence of oxygen, is a hallmark of cancer cells in culture. 2‐[18F]Fluoro‐2‐deoxyglucose‐positive tumors are assumed to metabolize glucose in a similar manner, with high rates of lactate formation relative to mitochondrial glucose oxidation, but few studies have specifically examined the metabolic fates of glucose in vivo. In particular, the capacity of human brain cancers to oxidize glucose in the tricarboxylic acid cycle is unknown. Here, we studied the metabolism of human brain tumors in situ. [U‐13 C]Glucose (uniformly labeled glucose, i.e. d ‐glucose labeled with 13 C in all six carbons) was infused during surgical resection, and tumor samples were subsequently subjected to 13C NMR spectroscopy. The analysis of tumor metabolites revealed lactate production, as expected. We also determined that pyruvate dehydrogenase, turnover of the tricarboxylic acid cycle, anaplerosis and de novo glutamine and glycine synthesis contributed significantly to the ultimate disposition of glucose carbon. Surprisingly, less than 50% of the acetyl‐coenzyme A pool was derived from blood‐borne glucose, suggesting that additional substrates contribute to tumor bioenergetics. This study illustrates a convenient approach that capitalizes on the high information content of 13C NMR spectroscopy and enables the analysis of intermediary metabolism in diverse cancers growing in their native microenvironment. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
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135.
Moore MR Hyde TB Hennessy TW Parks DJ Reasonover AL Harker-Jones M Gove J Bruden DL Rudolph K Parkinson A Butler JC Schuchat A 《The Journal of infectious diseases》2004,190(11):2031-2038
BACKGROUND: Streptococcus pneumoniae is a leading cause of invasive bacterial disease and pneumonia among children. Antimicrobial resistance among pneumococci has increased in recent years and complicates treatment. The introduction of heptavalent pneumococcal conjugate vaccine (PCV7) could reduce acquisition of antimicrobial-resistant pneumococci. METHODS: We obtained 1350 nasopharyngeal swabs for culture from 1275 children aged 3-59 months presenting at 3 clinics in Anchorage, Alaska, during the winters of 2000, 2001, and 2002, as PCV7 was being introduced into the routine immunization schedule. We recorded the frequency of use of antibiotics as well as the dates of doses of PCV7 for enrolled children. We used multivariate logistic regression modeling to identify independent risk factors for overall carriage of pneumococci and carriage of PCV7-type pneumococci, cotrimoxazole-nonsusceptible (COT-NS) pneumococci, or penicillin-nonsusceptible (PCN-NS) pneumococci. RESULTS: The proportion of children who were up-to-date for age, with respect to PCV7 vaccination, increased from 0% in 2000 to 55% in 2002. Carriage of PCV7-type pneumococci decreased by 43% (P<.0001). Risk of carriage of PCV7-type pneumococci was lower in 2002 than in 2000, independent of vaccination status, suggesting an indirect effect of vaccination. Carriage of COT-NS, but not PCN-NS, pneumococci also decreased (38%; P=.02), not only among vaccinated children but also among unvaccinated children without recent use of antibiotics. CONCLUSIONS: Introduction of PCV7 into the routine infant immunization schedule in a community with a high prevalence of antimicrobial-resistant pneumococci appears to reduce transmission of PCV7 vaccine serotypes and COT-NS pneumococci but has no impact on overall carriage of pneumococci or carriage of PCN-NS pneumococci. 相似文献
136.
Thomas O. Obisesan Robert E. Ferrell Dana A. Phares James M. Hagberg 《Metabolism: clinical and experimental》2008,57(12):1669-1676
The objective of the study was to determine whether ethnicity interacts with the APOE genotype to influence conventionally measured high-density lipoprotein cholesterol (HDL-C) subfraction levels and nuclear magnetic resonance-measured (HDLNMR-C) particle size at baseline and after training, and the changes with training. After a 6-week dietary stabilization period, men and postmenopausal women 50 to 75 years old underwent baseline testing (NMR lipid, maximum oxygen consumption, body composition, and genotyping assessments). Tests were repeated after completing 24 weeks of endurance exercise training. At baseline, APOE2/3 blacks had significantly larger particle size (P < .001) and higher total HDLNMR-C particle concentration (P = .006) than whites. After 6 months of endurance exercise training, APOE2/3 blacks maintained a significantly larger HDLNMR-C particle size (P < .001) and particle concentration of the large HDLNMR-C than APOE2/3 whites (P < .001). In multivariate analyses of variance adjusted for demographic and environmental confounding factors and for training-induced changes in lean body mass and intraabdominal fat, the model explained approximately 33% of the observed variability in training-induced improvements in HDLNMR-C particle size (P = .002), with APOE2/3 blacks having a greater increase in training-induced changes in HDLNMR-C particle size. In a separate but similarly adjusted model for conventionally measured HDL2-C, the model explained approximately 49% of the observed variability in training-induced changes in HDL2-C. Ethnicity interacted with the E2/3 genotype at the APOE gene locus to influence higher baseline and after-training levels, and greater exercise training-induced improvements in the advantageous HDL-C subfractions in blacks than in whites. APOE2/3 blacks may benefit more from aerobic fitness to reduce cardiovascular risk. 相似文献
137.
Banks MC Kamel NS Zabriskie JB Larone DH Ursea D Posnett DN 《The Journal of infectious diseases》2003,187(1):77-86
A comprehensive analysis of Staphylococcus aureus superantigen (SAG) genes was undertaken in isolates from a major hospital and compared with isolates from patients with toxic shock syndrome (TSS). Polymerase chain reaction (PCR) analysis included recently discovered SAGs. Staphylococcal enterotoxin (SE) G and SEI were uniquely expressed in genital isolates. Genital isolates were similar to TSS isolates, although the latter frequently expressed TSS toxin 1. Both had a high frequency of SEG/SEI and a high number of SAG genes per bacterium. Detection of an SAG gene by PCR correlated with positive results in functional assays for SAG activity. Levels of serum antibodies to SEG and SEI, but not to other superantigens, were higher in healthy women than in men and served as an independent measure of the higher frequency of exposure to SEG/SEI among women. Together, the data suggest a role for SEG/SEI or closely linked genes in the adaptation of S. aureus to the genital mucosa environment. 相似文献
138.
Dr. Charles F. Gholson MD Dana Favrot RN Benjamin Vickers MD David Dies MD William Wilder MD 《Digestive diseases and sciences》1996,41(5):831-834
To define the clinical significance of delayed postsphincterotomy hemorrhage, we reviewed 476 consecutive ERCP procedures performed over a three-year period. Of 250 patients who underwent endoscopic sphincterotomy (ES), five (2%) developed postprocedure hemorrhage, two of whom had immediate, self-limited bleeding that resolved after endoscopic injection of epinephrine and did not require transfusion. The other three had delayed hemorrhage characterized by: onset 20–48 hr after the procedure, melena without hematemesis as the index clinical manifestation of bleeding, and atraumatic balloon extraction of common duct stones. Transfusion of 2–6 units of packed erythrocytes was necessary in each and one patient required surgical hemostasis. Delayed hemorrhage following ERS is an important, frequently severe complication to remember when contemplating performing ERS as an outpatient procedure. 相似文献
139.
140.
PURPOSE: This study examines the relationship between the first set of quality measures (QMs) published by the Centers for Medicare and Medicaid Services on the Nursing Home Compare Web site and five nursing home structural characteristics: ownership, chain affiliation, size, occupancy, and hospital-based versus freestanding status. DESIGN AND METHODS: Using robust linear regressions, we examined the values of the QMs at first publication and their change over the first five reporting periods, in relation to facility characteristics. RESULTS: There were significant baseline differences associated with these facility characteristics. Pain, physical restraints, and delirium exhibit a clear downward trend, with differences between the first QM reporting period and the fifth ranging from 12.7% to 46.0%. However, there were only minimal differences in trends associated with facility characteristics. This suggests that the relative position of facilities on these measures did not change much within this time period. The variation by facility type was larger for the short-stay QMs than for the long-stay measures. IMPLICATIONS: Those QMs that show an improvement exhibit it across all types of facilities, irrespective of initial quality levels. Although a number of alternatives may explain this positive trend, the trend itself suggests that report cards, to the extent that they are effective, are so for all facility types but only some QMs. 相似文献