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41.
J. Harlaar J. J. Ten Kate A. J. H. Prevo T. W. Vogelaar G. J. Lankhorst 《Disability and rehabilitation》2013,35(11):453-461
Purpose: Cooling muscles might produce a temporary reduction of spasticity. This study investigated muscle coordination in spasticity under the influence of cooling. Methods: A repetitive movement (RM-) test of the ankle was used, while measuring the angle and surface-electromyography (EMG) of the m. tibialis anterior and m. triceps surae. Ensemble averaging provided quantified measures of muscle activation. Sixteen patients with spasticity in their lower extremity due to stroke or spinal cord injury participated in the study. Physical examination and the RM-test was done before and after cooling the m. triceps surae for 20 minutes by coldpacks. Results: The results show that Achilles hyperreflexia and clonus were abolished in all, and all but one patient, respectively. The EMG of the m. triceps surae, acting as a prime mover, was increased (p 0.028). However, this improved muscle coordination resulted in just a slightly increased active range of motion (less than 2 degrees at p 0.049). Conclusion: Apparently, the increase in excitability of the alpha motoneuron pool in voluntary movements of patients with spasticity is not followed by an improvement in the ability to move. 相似文献
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Ballester F Pérez-Hoyos S Rivera ML Merelles T Tenías JM Soriano JB Marín J Antó JM 《Archivos de bronconeumología》1999,35(1):20-26
The aim of this study was to describe the epidemiological characteristics of emergencies caused by asthma and chronic obstructive pulmonary disease (COPD) at the Hospital Clínico Universitario of Valencia (Spain) and to analyze factors related to hospital admissions for the same causes. Emergency room medical records for 1993 to 1995 of patients older than 14 years of age were examined to identify those due to asthma or COPD, according to established protocol. Demographic variables were described, followed by Poisson regression analysis of time and seasonal factors affecting emergencies. Factors related to hospital admission were analyzed by logistic regression, taking into account age group, sex, place of residence, and the year, month, day and hour of emergency room arrival. Asthma patients amounted to 1% of emergencies, while COPD patients accounted for 2%. The admission rate for women with asthma was higher than for men (F/M ratio = 0.78), whereas the rate for men with COPD was higher than for women (F/M ratio = 3.14). The largest age groups with asthma emergencies included young people aged 15 to 24 years old and those over 60. Hospital admissions or transfers to other hospitals were ordered for 17.4% of asthma patients and 38.8% of COPD patients. Nearly a third of COPD patients and a fifth of asthma patients were readmitted within the ten days following the first emergency. Clear temporal patterns of COPD emergency were observed for month (most occurring in winter), day of the week (most on Monday) and hour of the day (most during daytime hours, with fewer at midday). The time patterns were less evident for asthma emergencies, although the likelihood of admission because of asthma varied by month and day of the week. Emergency room records may be useful for studying the patterns of respiratory disease presentation. Other possible uses are epidemiologic monitoring and evaluation of health care quality. 相似文献
44.
Kara MA Smits ME Rosmolen WD Bultje AC Ten Kate FJ Fockens P Tytgat GN Bergman JJ 《Gastrointestinal endoscopy》2005,61(6):671-678
BACKGROUND: Light-induced fluorescence endoscopy (LIFE) may improve the detection of high-grade dysplasia (HGD) and early stage cancer (EC) in Barrett's esophagus (BE). The aim of this study was to compare LIFE with standard endoscopy (SE) in a randomized crossover study. METHODS: Fifty patients with BE underwent SE and LIFE in a randomized sequence (4 to 6-week interval between procedures). The two procedures were performed by two different endoscopists who were blinded to the findings of the other examination. Targeted biopsy specimens were taken from detected lesions, followed by random biopsy specimens with a 2-cm interval, 4-quadrant protocol. Biopsy specimens were routinely evaluated and subsequently reviewed by a single, blinded expert GI pathologist. RESULTS: Targeted biopsy specimens had a sensitivity for the diagnosis of HGD/EC of 62% (8/13) for both techniques. The overall sensitivity (all biopsy specimens) was 85% for SE and 69% for LIFE (p = 0.69). All targeted biopsy specimens had a positive predictive value (PPV) for HGD/EC of 41% for SE and 28% for LIFE (p = 0.40); autofluorescence-targeted biopsy specimens had a PPV of 13%. False-positive lesions had a significantly higher rate of acute inflammation than random biopsy specimens. CONCLUSIONS: In this study, LIFE did not improve the detection of HGD or EC in patients with BE compared with SE. 相似文献
45.
Lisa Rosenthal Valerie A. Earnshaw Tené T. Lewis Allecia E. Reid Jessica B. Lewis Emily C. Stasko Jonathan N. Tobin Jeannette R. Ickovics 《American journal of public health》2015,105(4):686-693
Objectives. We aimed to contribute to growing research and theory suggesting the importance of examining patterns of change over time and critical life periods to fully understand the effects of discrimination on health, with a focus on the period of pregnancy and postpartum and mental health outcomes.Methods. We used hierarchical linear modeling to examine changes across pregnancy and postpartum in everyday discrimination and the resulting consequences for mental health among predominantly Black and Latina, socioeconomically disadvantaged young women who were receiving prenatal care in New York City.Results. Patterns of change in experiences with discrimination varied according to age. Among the youngest participants, discrimination increased from the second to third trimesters and then decreased to lower than the baseline level by 1 year postpartum; among the oldest participants, discrimination decreased from the second trimester to 6 months postpartum and then returned to the baseline level by 1 year postpartum. Within-subjects changes in discrimination over time predicted changes in depressive and anxiety symptoms at subsequent points. Discrimination more strongly predicted anxiety symptoms among participants reporting food insecurity.Conclusions. Our results support a life course approach to understanding the impact of experiences with discrimination on health and when to intervene.A large and ever-growing body of research has shown that experiences with discrimination are associated with a wide range of adverse mental and physical health outcomes and may help explain socioeconomic and racial/ethnic health disparities in the United States.1,2 Although the majority of this research has been cross-sectional, an increasing number of longitudinal studies have shown that discrimination predicts poorer health.3,4 Some studies have gone further to examine within-person changes over time in discrimination and the resulting health implications.5–7Recently, Gee et al.8 proposed a life course perspective, calling for more research on changes in experiences with discrimination during critical periods to fully understand discrimination’s health effects and inform interventions. We examined changes across pregnancy and 1 year postpartum in experiences with everyday discrimination and consequences in terms of subsequent changes in depressive and anxiety symptoms among predominantly Black and Latina, socioeconomically disadvantaged young women residing in New York City. In their recent theoretical article, Gee et al. asserted:
Exposure to racism can change in nature, importance, and intensity. Similarly, health and the factors that produce health can change. A growing body of research shows that health is not merely the result of risks that occur sporadically at one point in time. Failure to attend to these temporal changes not only shortchanges our knowledge base, but also can lead to missed opportunities for intervention.8(p967)Cross-sectional (or even longitudinal) studies examining between-subjects associations of discrimination with health outcomes cannot assess changes in discrimination over time. To advance understanding of the health effects of discrimination, taking a life course perspective and examining changes in discrimination over time are crucial. Gee et al.8 highlighted potential age-patterned exposures to discrimination, with certain critical periods during which changes are more drastic. Some research supports this perspective, with evidence that racial discrimination increases across adolescence5 among African American youths and increases over time6 among African American, Latino, and Asian American youths. Although Gee et al. focused on racism, we suggest that their framework applies to all forms of discrimination.Pregnancy and postpartum may be a critical period to study changes in discrimination, given that women’s experiences with discrimination during pregnancy increase their likelihood of adverse maternal and infant health outcomes such as having a low birth weight infant9,10 and contracting a sexually transmitted infection.11 Also, women experience changes in their bodies, social relationships, and emotions12 during pregnancy and postpartum and come into contact with a variety of new social institutions, including those related to obstetrics and child care; thus, as a result of these life changes, women may experience changes in exposure to discrimination during this time period.8Changes in experiences with discrimination may also vary according to factors such as age, race/ethnicity, nativity, and socioeconomic status. Socioeconomically disadvantaged women, women of color, and women born outside of the United States who may have experienced discrimination regularly throughout their lives might feel that they are treated better or face less discrimination during pregnancy and the postpartum period, when people may extend them courtesies (e.g., giving up a seat on a bus) and institutions may offer added support (e.g., ensuring prenatal and infant care).By contrast, some theories suggest that Black and Latina women in the United States may experience heightened discrimination during pregnancy and postpartum because of group stereotypes related to sexuality and motherhood (e.g., sexual promiscuity, single parenthood) and the societal devaluation of motherhood in women of color.13,14 Some of these negative stereotypes specifically target Black and Latina adolescents and young women14 and so may be particularly relevant for younger age groups. Thus, experiences with discrimination can increase or decrease during pregnancy and postpartum, and the pattern of change may vary on the basis of characteristics such as age, race/ethnicity, nativity, and socioeconomic status. It is therefore important to assess these characteristics as potential moderators of changes in discrimination during this period.Discrimination is an important determinant of mental health across different social groups.1,2 The majority of research on discrimination and mental health is cross sectional; as noted, however, an increasing amount of research has explored this association longitudinally. For example, individual differences in Black Americans’ experiences with racial discrimination have been found to predict depressive and anxiety symptoms at a later time point, but differences in depressive and anxiety symptoms have not been found to predict racial discrimination at a later point.4,15Studies have begun to explore whether experiences with discrimination change over time and whether these changes are associated with changes in mental health. Schulz et al.7 found that changes over 2 time points (spaced 5 years apart) in Black American women’s experiences with discrimination were positively associated with simultaneous changes in depressive symptoms and negatively associated with changes in self-rated health.Greene et al.6 found that changes in experiences with discrimination across 5 time points (over 3 years) were negatively associated with simultaneous changes in self-esteem and positively associated with changes in depressive symptoms among Black, Latino, and Asian American high school students. Similarly, Brody et al.5 found that changes in experiences with racial discrimination across 3 time points (over 5 years) were positively associated with simultaneous changes in conduct problems and depressive symptoms among Black adolescents. To the best of our knowledge, despite this existing research on discrimination and depressive symptoms, no work has examined associations between changes in discrimination and changes in anxiety or assessed these associations during pregnancy.Yet, pregnancy and postpartum may be a particularly important period during which to examine associations of discrimination with depressive and anxiety symptoms. During pregnancy, these symptoms have adverse consequences for birth outcomes (e.g., preterm birth and low birth weight) and infant development (e.g., cognitive and motor development).16 In the postpartum period, these symptoms have adverse consequences with respect to parenting behaviors (e.g., playing with and talking to the infant) and the health of both the mother and the child.17 In addition, although past research suggests that discrimination has adverse mental health consequences across diverse groups, much of this research has focused on specific groups (e.g., Black Americans), and thus it is important to examine whether these associations vary according to factors such as age, race/ethnicity, nativity, and socioeconomic status.The first aim of our study was to examine changes in experiences with discrimination across pregnancy and 1 year postpartum and assess whether age, race/ethnicity, nativity, or socioeconomic status moderated the pattern of change. Our second aim was to explore whether changes in experiences with discrimination over time predicted changes in depressive and anxiety symptoms at subsequent points and whether the sociodemographic factors just described moderated these associations.Given the competing theories described earlier, we did not have a specific expected pattern of change; rather, we hypothesized that experiences with discrimination would change across pregnancy and the postpartum period and that age, race/ethnicity, nativity, or socioeconomic status of participant might moderate that pattern. Also, consistent with past work showing associations between discrimination and mental health across diverse groups, we hypothesized that changes in experiences with discrimination across pregnancy and postpartum would significantly positively predict changes in depressive and anxiety symptoms at subsequent time points and that participants’ age, race/ethnicity, nativity, and socioeconomic status would not moderate those associations. 相似文献
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OBJECTIVE: The aim was to evaluate the applicability of myocardial contrast echocardiography in the measurement of coronary flow reserve. METHODS: Eleven anaesthetised open chest pigs were studied, in which coronary atherosclerosis had been induced by abrasion of the left anterior descending coronary artery at one month, followed by an atherogenic diet for eight months. Coronary flow reserve was determined by electromagnetic flow measurement and contrast echocardiography before and after partial occlusion of the left anterior descending coronary artery, using papaverine as a coronary vasodilator. Coronary blood flow was reduced by tightening a clamp placed around the coronary artery. Systemic haemodynamics and myocardial wall thickness (epicardial ultrasound 5 MHz transducer) were recorded simultaneously. Echocardiograms were recorded on VHS tape and analysed by digitised videodensitometry off line for construction of the time v videointensity curve (time-intensity curves). From these curves washout time (T50), area under the curve, peak contrast intensity, and time to peak intensity were calculated. RESULTS: Following papaverine, coronary blood flow increased significantly from 47 (SD 23) ml.min-1 at baseline to 88(39) ml.min-1 (p less than 0.05). During the stenosis, flow decreased to 19(16) ml.min-1 (p less than 0.01), and increased to 38(29) ml.min-1 (p less than 0.05 v stenosis) after administration of papaverine. Correlations between coronary blood flow and indices calculated from the quantitative videodensitometric analysis were poor, varying between r = 0.03 for area at control flow to r = 0.62 for T50 during stenosis. The same was true for coronary flow reserve: r = 0.09 for peak to r = 0.75 (p less than 0.05) for time to peak without the stenosis. CONCLUSIONS: Current limitations in injection, imaging, and analysis techniques cause variability in data from time-intensity curves, which precludes accurate quantification of coronary flow (reserve) by myocardial contrast echocardiography. 相似文献
48.
Meliga E Steendijk P Valgimigli M Ten Cate FJ Serruys PW 《The American journal of cardiology》2008,101(8):1179-1184
The aim of the present study was to determine the long-term effects of percutaneous transluminal septal myocardial ablation (PTSMA) on systolic and diastolic left ventricular (LV) functions in patients with obstructive hypertrophic cardiomyopathy (HC). Ten consecutive patients with symptomatic HC despite optimal medical treatment were referred for PTSMA at our center. LV systolic and diastolic functions were assessed by online LV pressure-volume loops obtained by conductance catheter at baseline and at 6 months after the procedure. At follow-up, the mean gradients at rest and after extrasystole were significantly decreased compared with baseline (88 +/- 29 to 21 +/- 11 mm Hg and 130 +/- 50 to 35 +/- 22 mm Hg, respectively, p <0.01 for the 2 comparisons). End-systolic and end-diastolic pressures significantly decreased (p <0.01), whereas end-systolic and end-diastolic LV volumes significantly increased (p <0.01 for the 2 comparisons). Cardiac output and stroke volume were unchanged, as were ejection fraction (p = 0.25) and maximum dP/dt (p = 0.13). The slope of the end-systolic pressure-volume relation was not decreased, indicating a preserved contractility. The relaxation constant time, end-diastolic stiffness, projected volume of the end-diastolic pressure-volume relation at 30 mm Hg, and diastolic stiffness constant showed a significant improvement of active and passive myocardial diastolic properties. In conclusion, PTSMA is an effective method in the treatment of symptomatic patients with HC. At 6-month follow-up, the LV-aortic gradient was decreased and active and passive LV diastolic properties were increased. Myocardial contractility was not decreased and general hemodynamics was maintained. 相似文献
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50.
Accuracy of conventional digital palpation and ultrasound of the cricothyroid membrane in obese women in labour 下载免费PDF全文
Success of cricothyroidotomy depends on accurate identification of anatomical neck landmarks. Anaesthetists palpated the cricothyroid membrane of 28 obese and 28 non‐obese women in labour (cut‐off BMI 30 kg.m?2) and marked the entry point for device insertion with an ultraviolet invisible pen. Ultrasonography was used to mark the midpoint of the cricothyroid membrane and the distance between the two marks was measured. The median (IQR [range]) distance between the two marks was significantly greater in the obese than the non‐obese patients (5 (2–9.5 [0–34]) mm vs 1.8 (0.1–6 [0–15]) mm, respectively; p = 0.02). The cricothyroid membrane was accurately identified with digital palpation in only 39% (11/28) of obese compared with 71% (20/28) of non‐obese patients (p = 0.03). Increased neck circumference in obese patients was significantly associated with inaccuracy in locating the cricothyroid membrane. Percutaneous identification of the cricothyroid membrane in obese women in labour was poor. Pre‐procedural ultrasound may help improved the identification of neck landmarks for cricothyroidotomy. 相似文献