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31.
32.
PurposeTo explore trends in teen birth rates by selected demographics.MethodsWe used birth certificate data and joinpoint regression to examine trends in teen birth rates by age (10–14, 15–17, and 18–19 years) and race during 1981–2006 and by age and Hispanic origin during 1990–2006. Joinpoint analysis describes changing trends over successive segments of time and uses annual percentage change (APC) to express the amount of increase or decrease within each segment.ResultsFor teens younger than 18 years, the decline in birth rates began in 1994 and ended in 2003 (APC: ?8.03% per year for ages 10–14 years; APC: ?5.63% per year for ages 15–17 years). The downward trend for 18- and 19-year-old teens began earlier (1991) and ended 1 year later (2004) (APC: ?2.37% per year). For each study population, the trend was approximately level during the most recent time segment, except for continuing declines for 18- and 19-year-old white and Asian/Pacific Islander teens. The only increasing trend in the most recent time segment was for 18- and 19-year-old Hispanic teens. During these declines, the age distribution of teens who gave birth shifted to slightly older ages, and the percentage whose current birth was at least their second birth decreased.ConclusionsTeen birth rates were generally level during 2003/2004–2006 after the long-term declines. Rates increased among older Hispanic teens. These results indicate a need for renewed attention to effective teen pregnancy prevention programs in specific populations.  相似文献   
33.
Background: Whether psychological resilience correlates with neurocognitive performance is largely unknown. Therefore, we assessed association between neurocognitive performance and resilience in individuals with a history of childhood abuse or trauma exposure. Methods: In this cross‐sectional study of 226 highly traumatized civilians, we assessed neurocognitive performance, history of childhood abuse and other trauma exposure, and current depressive and PTSD symptoms. Resilience was defined as having ≥1 trauma and no current depressive or PTSD symptoms; non‐resilience as having ≥1 trauma and current moderate/severe depressive or PTSD symptoms. Results: The non‐resilient group had a higher percentage of unemployment (P=.006) and previous suicide attempts (P<.0001) than the resilient group. Both groups had comparable education and performance on verbal reasoning, nonverbal reasoning, and verbal memory. However, the resilient group performed better on nonverbal memory (P=.016) with an effect size of .35. Additionally, more severe childhood abuse or other trauma exposure was significantly associated with non‐resilience. Better nonverbal memory was significantly associated with resilience even after adjusting for severity of childhood abuse, other trauma exposure, sex, and race using multiple logistic regression (adjusted OR=1.2; P=.017). Conclusions: We examined resilience as absence of psychopathology despite trauma exposure in a highly traumatized, low socioeconomic, urban population. Resilience was significantly associated with better nonverbal memory, a measure of ability to code, store, and visually recognize concrete and abstract pictorial stimuli. Nonverbal memory may be a proxy for emotional learning, which is often dysregulated in stress‐related psychopathology, and may contribute to our understanding of resilience. Depression and Anxiety, 2010. © 2010 Wiley‐Liss, Inc.  相似文献   
34.
Systemic lupus erythematosus characteristically afflicts women of reproductive age, yet the explanation for this feature is unknown. This hospital-based, case-control study of 109 incident cases of systemic lupus erythematosus and 109 randomly selected controls was conducted to search for risk factors related to reproduction. Women who were 34 years of age and younger had a crude risk of systemic lupus erythematosus 3.6 times that of older women, and women who were of minority races had a crude risk 4.8 times that of white women (P less than 0.001). Prior hysterectomy or tubal sterilization had a significant protective effect (odds ratio, 0.55; 95% confidence interval, 0.31 to 0.99). Endometriosis was associated with a twofold increased risk of systemic lupus erythematosus, although this was not statistically significant. The latter two findings are consistent with the hypothesis that retrograde menstruation may be an inciting factor for systemic lupus erythematosus in susceptible women.  相似文献   
35.
In this article we would like to highlight uterine pseudoaneurysm as a cause of secondary post‐partum haemorrhage following Caesarean section. We would like to stress Doppler ultrasound scan as the initial screening modality for this condition. We also describe angioembolization as the prudent treatment option for this condition rather than resorting to surgery.  相似文献   
36.
For most of the 20th century, most drugs labeled by the United States Food and Drug Administration (USFDA) have not been adequately studied in the pediatric population. This lack of data has necessitated the continued dependence of practitioners on sub-optimal prescribing data placing pediatric patients at great risk of serious therapeutic misadventures. Recently, the USFDA has enacted and begun to enforce the Final Rule of 1997 which became effective on 1 April 1999. This rule is the culmination of the persistent efforts of numerous professional organizations, clinicians, academicians, the USFDA and others, to ensure the ready availability of appropriate data for medications intended for or that will be used in children. Unlike the 1994 Rule which voluntarily required pharmaceutical manufacturers to submit pediatric data, the Final Rule mandates submission of such data and, most importantly, empowers the USFDA to afford incentives and penalties for non-compliance including possible removal of already marketed products. This overview addresses many of the important components which must be included in the performance of a comprehensive clinical pharmacologic evaluation serving as the foundation for optimal dosing across the broad age range encompassing pediatric practice. Furthermore, the possible risk and/or benefits of the study must be reasonably defined prior to undertaking the study and clearly shared with the patient's caregivers. Consent should always be obtained from the caregiver and, when appropriate, assent obtained from the underage child. To facilitate such clinical investigations and to foster collaborative efforts with innovators and clinical research programs, the National Institutes of Health through the National Institute of Child Health and Human Development of the NIH established a network of Pediatric Pharmacology Research Units. These units have worked closely together and with other pediatric research centers to facilitate USFDA labeling of a number of commonly used medications. All of these very positive efforts highlight the many challenges that remain for the pediatric investigator and practitioner while underscoring the very positive environment in support of these efforts.  相似文献   
37.
Although exposure of LLC-PK1 epithelial cell sheets to phorbol esters (TPA) causes a near immediate and total decrease of transepithelial electrical resistance (TER), continuation of exposure for 3 to 4 days results in a tachyphylactic response as TER begins to return to control levels. Recovery of TER is maximal by 5 to 6 days, but reaches only 70 to 80% of control level. A reciprocal change in the transepithelial flux of D-mannitol indicates that the TER decrease is indicative of an increase in tight junction permeability. Exposure of cell sheets to TPA for several days also results in the appearance of multilayered polyp- like foci (PLFs) across the otherwise one cell layer thick cell sheets. The pattern of penetration of the electron dense dye, ruthenium red, from the apical surface, across the tight junction and into the lateral intercellular space indicates that the tight junctions of the cell sheet become uniformly leaky after acute exposure to TPA. However, when exposure is continued for several days, only the junctions of cells in the PLFs manifest leakiness. The decrease in TER following acute TPA exposure correlates with the translocation of protein kinase C-alpha (PKC alpha) into a membrane-associated compartment. With exposure of several days, only a trace of PKC alpha is visible by Western immunoblot, and this is in the membrane-associated compartment. Immunofluorescent microscopy indicates that the trace of PKC alpha seen in the Western immunoblots is ascribable distinctly to cells of the PLFs. Monolayer areas between PLFs show no discernible immunofluorescent signal. The data therefore indicate that tight junction barrier function may be restored in certain areas by the down regulation of PKC alpha from the membrane-associated compartment. Failure to down regulate may result in the paracellular leakiness and abnormal cell architecture of the PLFs. Possible implications of this model for in vivo epithelial tumor promotion are discussed.   相似文献   
38.
It is postulated that a vigorous host inflammatory response in the cystic fibrosis lung contributes to lung injury. Tumour necrosis factor-alpha (TNF-alpha) may play a part in that process and in the generation of leukotrienes. Therefore, the relationships between sputum TNF-alpha, leukotriene concentration, and lung function abnormalities in 16 children with cystic fibrosis were investigated. Each subject provided sputum samples and performed spirometry. TNF-alpha was measured by enzyme linked immunosorbent assay; individual leukotrienes were separated using high performance liquid chromatography and quantified by radioimmunoassay. The geometric mean concentration of TNF-alpha was 129.7 pg/ml and 95% confidence interval 48.2 to 348.3. Mean (SEM) leukotriene B4 (LTB4) was 97.8 (22.9) pmol/g and total cysteinyl leukotrienes were 60.9 (14.8) pmol/g. Mean (SD) forced expiratory volume in one second (FEV1) of the group was 53 (15)% of predicted and forced vital capacity (FVC) was 65 (14)% of predicted. There was a significant positive correlation between TNF-alpha and both LTB4 and the total cysteinyl leukotriene sputum content. An inverse relationship existed between TNF-alpha and FEV1 and FVC. Moreover, a negative correlation was observed between sputum LTB4 and FEV1 and FVC. These results suggest that TNF-alpha and the leukotrienes may participate in the airways inflammation and airflow obstruction observed in cystic fibrosis subjects and support the hypothesis that TNF-alpha upregulates the 5-lipoxygenase pathway in vivo.  相似文献   
39.
A new amino acid mixture for incorporation into medical foods for the treatment of hyperphenylalaninemia has been tested in a regular clinic. The mix is designed to be as unobtrusive as possible, consistent with good nutrition. After more than 1 year of trial as a beverage, we have shown that it is safe and well tolerated but that plasma phenylalanine is no better controlled than with some other products. The mix can be incorporated into a large number of different foods without affecting the taste. Occult monitoring of the quantity of medical foods purchased compared with the amounts reported to be consumed in diet histories provides an excellent way to monitor dietary compliance.  相似文献   
40.
The Surveillance Research Program of the American Cancer Society's Department of Epidemiology and Surveillance Research reports its annual compilation of estimated cancer incidence, mortality, and survival data for the United States in the year 2000. After 70 years of increases, the recorded number of total cancer deaths among men in the US declined for the first time from 1996 to 1997. This decrease in overall male mortality is the result of recent down-turns in lung and bronchus cancer deaths, prostate cancer deaths, and colon and rectum cancer deaths. Despite decreasing numbers of deaths from female breast cancer and colon and rectum cancer, mortality associated with lung and bronchus cancer among women continues to increase. Lung cancer is expected to account for 25% of all female cancer deaths in 2000. This report also includes a summary of global cancer mortality rates using data from the World Health Organization.  相似文献   
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