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排序方式: 共有3763条查询结果,搜索用时 781 毫秒
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Duffy AJ Nolan B Sheth K Collette H De M Bankey PE 《The Journal of surgical research》2000,90(1):51-57
BACKGROUND: Altered transendothelial migration and delayed apoptosis of neutrophils (PMN) have been implicated as contributing to infection in patients with gram-negative sepsis. Macrophage inflammatory protein 2 (MIP-2) signals PMN immigration and may alter other PMN functions. We tested the hypothesis that sequential endotoxin challenge in vivo alters PMN apoptosis and chemotactic responses. MATERIALS AND METHODS: Endotoxemia was induced in male Wistar rats (250 g) via intraperitoneal (IP) administration of LPS (4 mg/kg). After 18 h, intratracheal (IT) injection of LPS (400 microg/kg) was performed. Control animals received saline injections. Four hours after IT-LPS, circulating and bronchoalveolar lavage (BAL) PMN were isolated. PMN yields were calculated, and apoptosis was quantified after 18 h in culture by annexin V-fluorescein isothiocyanate FACS analysis. BAL MIP-2 concentrations were determined by ELISA. PMN chemotaxis to MIP-2 and IL-8 was determined using a fluorescent in vitro migration assay. RESULTS: Endotoxemia (IP-LPS) significantly decreases BAL PMN yield in response to an in vivo IT-LPS challenge. IT-LPS inhibits BAL PMN apoptosis to the same extent as sequential IP/IT-LPS. Alveolar MIP-2 concentrations are similar in the two groups. In vitro migration to IL-8 and MIP-2 was inhibited in PMN from endotoxemic versus control animals. CONCLUSIONS: These data demonstrate that endotoxemia inhibits PMN migration despite similar MIP-2 concentrations in the alveolus. Sequential insults do not affect the inhibition of apoptosis. In vitro, PMN from endotoxemic animals display impaired chemotaxis to MIP-2 and interleukin-8. This may result in an inadequate host defense that contributes to increased ICU-acquired pneumonia in septic patients. 相似文献
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Kristin M Rosen Raymond D Kent Amy L Delaney Joseph R Duffy 《J. Speech Lang. Hear. Res.》2006,49(2):395-411
PURPOSE: This study's main purpose was to (a) identify acoustic signatures of hypokinetic dysarthria (HKD) that are robust to phonetic variation in conversational speech and (b) determine specific characteristics of the variability associated with HKD. METHOD: Twenty healthy control (HC) participants and 20 participants with HKD associated with idiopathic Parkinson's disease (PD) repeated 3 isolated sentences (controlled phonetic content) and 2 min of conversational speech (phonetic content treated as a random variable). A MATLAB-based program automatically calculated measures of contrastivity: speech-pause ratio, intensity variation, median and maximum formant slope, formant range, change in the upper and lower spectral envelope, and range of the spectral envelope. t tests were used to identify which measures were sensitive to HKD and which measures differed by task. Discriminant analysis was used to identify the combination of measures that best predicted HKD, and this analysis was then used as a general measure of contrastivity (Contrastivity Index). Differential effects of HKD on maximum and typical contrastivity levels were tested with interaction of maximum, minimum, and median observations of individual speakers and with pairwise comparisons of skewness and kurtosis of the contrastivity index distributions. RESULTS: Group differences were detected with pairwise comparisons with t tests in 8 of the 9 measures. Percentage pause time and spectral range were identified as the most specific (95%) and accurate (95%) differentiators of HKD and HC conversational speech. Sentence repetition elicited significantly higher levels of contrastivity than conversational speech in both HC and HKD speakers. Maximum and minimum contrastivities were significantly lower in HKD speech, but there was no evidence that HKD affects maximum contrastivity levels more than median contrastivity levels. The HKD speakers' contrastivity distributions were significantly more skewed to lower levels of production. CONCLUSION: HKD can be consistently distinguished from HC speech in both sentence repetition and conversational speech on the basis of intensity variation and spectral range. Although speakers with HKD were effectively able to produce higher contrastivity levels in sentence repetition tasks, they habitually performed closer to the lower end of their production ranges. 相似文献
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PURPOSE: Young women who undergo chemotherapy for breast cancer face serious consequences to their reproductive health. Research in this area has previously focused on men, or on childhood cancer survivors. We sought to explore self-report of reproductive health counseling in young women undergoing chemotherapy for breast cancer. PATIENTS AND METHODS: A total of 166 premenopausal women aged < or = 50 years were recruited from oncology offices in academic and private practices in four northeastern states, as part of a randomized controlled clinical trial aimed at stress reduction. Women were asked a variety of questions regarding diagnosis and treatment, including whether they received any counseling regarding early menopause and fertility issues. RESULTS: Sixty-eight percent and 34% of women reported recalling a discussion with a physician regarding early menopause or fertility, respectively. In multivariate analysis, hormonal therapy and early stage of disease were associated with significantly increased odds of recall of a discussion regarding menopause. Difficulty communicating with medical team was associated with increased odds of recalling a discussion regarding fertility, whereas older age and anxiety in medical situations were associated with decreased odds. CONCLUSION: Many women fail to recall discussions regarding the reproductive health impact of chemotherapy. Demographic, psychological, and disease-related variables are related to recalling such discussions. Counseling about premature menopause and fertility changes is an overlooked aspect of preparation for adjuvant chemotherapy in young premenopausal women with breast cancer. Future research should explore this issue further. 相似文献
65.
Alessandro Mussa Kelly A. Duffy Diana Carli Giovanni Battista Ferrero Jennifer M. Kalish 《Pediatric blood & cancer》2019,66(1)
Patients with Beckwith‐Wiedemann spectrum (BWSp) undergo quarterly alpha‐fetoprotein measurement for hepatoblastoma (HB) screening up to 4 years of age, paralleling the epidemiology of nonsyndromic HB. However, specific data on the timing of HB development in BWSp are lacking. Here we compare the timing of presentation of HBs in BWSp with a control cohort of consecutive HB cases, demonstrating that halving screening duration of screening procedures in BWSp likely will not impact its effectiveness. 相似文献
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Factors that affect implementation of a nurse staffing directive: results from a qualitative multi‐case evaluation
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