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1.
PurposeMore teens delay in driving licensure (DDL). It is conceivable they miss Graduated Driver Licensing (GDL) safety benefits. We assessed prevalence, disparities, and factors associated with DDL among emerging adults.MethodsData used were from all seven waves (W1–7) of the NEXT Generation Health Study (W1 in 10th grade [2009–2010]). The outcome variable was DDL (long-DDL [delayed >2 years], intermediate-DDL [delayed 1–2 years] versus no-DDL), defined as participants receiving driver licensure ≥1 year after initial eligibility. Independent variables included sex, urbanicity, race/ethnicity, family structure, parental education, family affluence, parental monitoring knowledge, parent perceived importance of alcohol nonuse, and social media use. Logistic regressions were conducted.ResultsOf 2,525 participants eligible for licensure, 887 (38.9%) reported intermediate-DDL and 1,078 (30.1%) long-DDL. Latinos (adjusted odds ratio [AOR] = 2.5 vs. whites) and those with lower affluence (AOR = 2.5 vs. high) had higher odds of intermediate-DDL. Latinos (AOR = 4.5 vs. whites), blacks (AOR = 2.3 vs. whites), those with single parent (AOR = 1.7 vs. both biological parents), whose parents’ education was high school or less (AOR = 3.7 vs. bachelor+) and some college (AOR = 2.0 vs. bachelor+) levels, and those with lower affluence (AOR = 4.4 vs. high) had higher odds of long-DDL. Higher mother’s monitoring knowledge (AOR = .6) was associated with lower odds of long-DDL, but not intermediate-DDL.ConclusionsSome teens that DDL “age out” of protections afforded to them by GDL driver restrictions. Minority race/ethnicity, socioeconomic status, urbanicity, and parenting factors contribute to DDL. Further study of these factors and their individual/collective contributions to DDL is needed to understand potential unintended consequences of GDL, particularly in more vulnerable youth.  相似文献   
2.
What will it take to develop interventions for the treatment of age-related cognitive decline? Session V of the Summit provided perspectives on the design of clinical trials to evaluate promising but unproven interventions, and some of the steps needed to accelerate the discovery and evaluation of promising treatments. It considered strategies to further characterize the biological and cognitive changes associated with normal aging and their translation into the development of new treatments. It provided regulatory, scientific, and clinical perspectives about neurocognitive aging treatments, their potential benefits and risks, and the strategies and endpoints needed to evaluate them in the most rapid, rigorous, and clinically meaningful way. It considered lessons learned from the study of Alzheimer's disease, the promising roles of biomarkers in neurocognitive aging research, and ways to help galvanize the scientific study and treatment of neurocognitive aging.  相似文献   
3.
Spatially varying distortions (SVDs) are common artifacts of spectacles like progressive additional lenses (PALs). To habituate to distortions of PALs, the visual system has to adapt to distortion-induced image alterations, termed skew adaptation. But how this visual adjustment is achieved is largely unknown. This study examines the properties of visual adaptation to distortions of PALs in natural scenes. The visual adaptation in response to altered form and motion features of the natural stimuli were probed in two different psychophysical experiments. Observers were exposed to distortions in natural images, and form and motion aftereffects were tested subsequently in a constant stimuli procedure where subjects were asked to judge the skew, or the motion direction of an according test stimulus.Exposure to skewed natural stimuli induced a shift in perceived undistorted form as well as motion direction, when viewing distorted dynamic natural scenes, and also after exposure to static distorted natural images. Therefore, skew adaptation occurred in form and motion for dynamic visual scenes as well as static images. Thus, specifically in the condition of static skewed images and the test feature of motion direction, cortical interactions between motion-form processing presumably contributed to the adaptation process.In a nutshell, interfeature cortical interactions constituted the adaptation process to distortion of PALs. Thus, comprehensive investigation of adaptation to distortions of PALs would benefit from taking into account content richness of the stimuli to be used, like natural images.  相似文献   
4.
Plasma free insulin was measured repeatedly for 4 hours following a standardized breakfast in 20 C-peptide negative chronically pumped type I diabetic patients and 5 normal subjects. In the former group, insulin was given as a 1 u/h basal infusion and a 1h superimposed meal-dose of 6 u via a peritoneal (IP) catheter lying in the low (n = 10), or in the mid-abdomen (n = 10). The results of the IP patients were correlated with glycosylated haemoglobin and home capillary blood glucose. Fasting free insulin of IP patients was lower than those of normals (14.7 +/- 0.5 vs 21.0 +/- 1.3 mU/l, p less than 0.01). Dose-induced peak occurred similarly in IP patients and normals (70 +/- 6 vs 70 +/- 12 min.). Values tended to baseline after 165 +/- 15 and 185 +/- 22 min. in IP patients and normals (NS). Results of the mid--and low peritoneum subgroups differed only for peak values (31.5 +/- 2.9 vs 25.0 +/- 1.6 mU/l respectively) and did not correlate with diabetic control.  相似文献   
5.
Empty follicle syndrome in two sisters with three cycles: case report   总被引:4,自引:0,他引:4  
Empty follicle syndrome (EFS) is characterized by a lack of retrieved oocytes in the presence of multiple follicle development, in both natural and stimulated cycles. The aim of the present case report is to point out the possibility of genetic factors that could be responsible for some occurrences of EFS. Two sisters with moderate deafness underwent controlled ovarian hyperstimulation and IVF/ICSI cycles at the same centre. During all three cycles there were normal follicular development, estradiol levels and bio-available hCG plasma levels, but no oocytes and cumulus-corona complexes were retrieved, despite second hCG injections. These cases may represent an inherited condition of EFS with hearing loss with genetic factors affecting both the aetiology of EFS and the hearing loss.  相似文献   
6.
OBJECTIVE: This study was undertaken to determine whether estrogen down-regulates vascular monocyte chemotactic protein-1 expression during the development of atherosclerosis in vivo and to identify the cellular localization of monocyte chemotactic protein-1 expression under baseline conditions and in response to atherogenic stimuli. STUDY DESIGN: Female, homozygous low-density lipoprotein-receptor-deficient mice (n = 68) in a C57BL/6 background underwent ovariectomy, were implanted subcutaneously with 17beta-estradiol or placebo pellets, and were changed to a high cholesterol (1.25%) diet. Thereafter, four mice from each group were killed weekly for 8 weeks, and their aortae were frozen for immunohistochemical analysis. The lipid deposition was identified by Sudan black B staining. Monocyte chemotactic protein-1 expression was detected with a rabbit anti-mice monocyte chemotactic protein-1 antibody, and semiquantitative analysis was performed. RESULTS: Consistent with previous reports, estradiol resulted in diminished vascular lipid deposition (22% +/- 7% vs 15% +/- 6% at 8 weeks of gestation, P <.05). We found that the inhibition of lipid deposition in aortae of animals that were treated with estrogen is associated with a concomitant down-regulation of monocyte chemotactic protein-1 immunoreactivity in aortic endothelial and smooth muscle cells (P <.05). Serum total cholesterol concentrations did not differ between the two treatment groups, which suggests a direct effect of estradiol on the aorta. CONCLUSION: Our findings suggest that one of the mechanisms by which estrogen down-regulates atherogenesis is by the suppression of vascular monocyte chemotactic protein-1 expression, which leads to decreased macrophage recruitment to the arterial wall early in the process.  相似文献   
7.
8.
Summary Remission of diabetes was attempted in 12 recent acute onset ketosis-prone juvenile diabetes after short term (5±1 days) but excellent blood glucose control by the external artificial beta-cell. The comparison group comprised patients undergoing traditional treatment (n=28). Nine (75%) persistent (over 3–14 months of duration) although partial (oral drugs required) remissions were obtained in the former group as compared to 3 (11%) in the latter group (p<0.05). Cases which showed remissions after insulin infusion had a plasma insulin response to IV glucagon still present before insulin infusion, and a daily urinary C-peptide excretion significantly enhanced after (p<0.01). Urinary C-peptide /blood glucose remained improved during the remission period. Thus, early effective treatment by means of the artificial pancreas may break the vicious circle hyperglycaemia-insulin depletion-hyperglycaemia and lead to frequent and sustained remissions of juvenile diabetes.  相似文献   
9.
The Predictable Results and Experience in Diabetes through Intensification and Control to Target: An International Variability Evaluation 303 (PREDICTIVE 303) Study (n = 5604) evaluated the effectiveness of insulin detemir, a long-acting basal insulin analogue, using a simplified patient self-adjusted dosing algorithm (303 Algorithm group) compared with standard-of-care physician-driven adjustments (Standard-of-care group) in a predominantly primary care setting, over a period of 6 months. Insulin detemir was to be started once-daily as add-on therapy to any other glucose-lowering regimens or as a replacement of prestudy basal insulin in patients with type 2 diabetes. Investigator sites rather than individual patients were randomized to either the 303 Algorithm group or the Standard-of-care group. Patients from the 303 Algorithm group sites were instructed to adjust their insulin detemir dose every 3 days based on the mean of three 'adjusted' fasting plasma glucose (aFPG) values (capillary blood glucose calibrated to equivalent plasma glucose values) using a simple algorithm: mean aFPG < 80 mg/dl (<4.4 mmol/l), reduce dose by 3 U; aFPG between 80 and 110 mg/dl (4.4-6.1 mmol/l), no change; and aFPG > 110 mg/dl (>1.1 mmol/l), increase dose by 3 U. The insulin detemir dose for patients in the Standard-of-care group was adjusted by the investigator according to the standard of care. Mean A1C decreased from 8.5% at baseline to 7.9% at 26 weeks for the 303 Algorithm group and from 8.5 to 8.0% for the Standard-of-care group (p = 0.0106 for difference in A1C reduction between the two groups). Mean FPG values decreased from 175 mg/dl (9.7 mmol/l) at baseline to 141 mg/dl (7.8 mmol/l) for the 303 Algorithm group and decreased from 174 mg/dl (9.7 mmol/l) to 152 mg/dl (8.4 mmol/l) for the Standard-of-care group (p < 0.0001 for difference in FPG reduction between the two groups). Mean body weight remained the same at 26 weeks in both groups (change from baseline 0.1 and -0.2 kg for the 303 Algorithm group and the Standard-of-care group respectively). At 26 weeks, 91% of the patients in the 303 Algorithm group and 85% of the patients in the Standard-of-care group remained on once-daily insulin detemir administration. The rates of overall hypoglycaemia (events/patient/year) decreased significantly from baseline in both groups [from 9.05 to 6.44 for the 303 Algorithm group (p = 0.0039) and from 9.53 to 4.95 for the Standard-of-care group (p < 0.0001)]. Major hypoglycaemic events were rare in both groups (0.26 events/patient/year for the 303 Algorithm group and 0.20 events/patient/year for the Standard-of-care group; p = 0.2395). In conclusion, patients in the 303 Algorithm group achieved comparable glycaemic control with higher rate of hypoglycaemia as compared with patients in the Standard-of-care group, possibly because of more aggressive insulin dose adjustments. The vast majority of the patients in both groups were effectively treated with once-daily insulin detemir therapy. The use of insulin detemir in this predominantly primary care setting achieved significant improvements in glycaemic control with minimal risk of hypoglycaemia and no weight gain.  相似文献   
10.
Our objective was to compare the pregnancy complications and neonatal outcomes of multifetal pregnancies reduced to twins to those in twin pregnancies without multifetal pregnancy reduction (MPR). A cohort study was performed in patients with dichorionic twin pregnancies who reached 24 weeks' gestation and delivered at the Mount Sinai Medical Center between 1986 and 1997. A study population of 77 multifetal pregnancies reduced to twins were compared with 140 dichorionic twin pregnancies without MPR regarding pregnancy complications and neonatal outcomes. Statistical analysis was performed with Chi-square and two-tailed Student's t-tests. Multifetal pregnancies reduced to twins were similar to nonreduced twins in all parameters studied except the cesarean section rate and neonatal polycythemia. Increased cesarean section rate in MPR group was attributed to elective indications. Pregnancy-induced hypertension was found to be higher only in a subgroup of patients (i.e., 4-2). Multifetal pregnancies reduced to twins do not differ from the twin pregnancies without MPR in the overwhelming majority of pregnancy complications and neonatal outcomes.  相似文献   
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