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91.
92.
Childhood sexual abuse (CSA) is associated with HIV sexual risk behavior. Although many psychosocial correlates of sexual
risk among HIV-positive persons have been identified, studies predicting continued risk among HIV-positive adults with histories
of CSA are limited. This cross-sectional study identified variables predictive of sexual transmission risk behavior among
an ethnically diverse sample of 256 HIV-positive adults (women and men who have sex with men; MSM) with CSA histories. Participants
were assessed for trauma symptoms, shame related to HIV and sexual trauma, substance use, coping style, and sexual risk behavior.
Logistic regression analyses were conducted to identify variables predictive of unprotected sexual behavior in the past 4 months.
Unprotected sex was significantly associated with substance use and trauma-related behavioral difficulties among women and
men, and less spiritual coping among men. Unprotected sex with HIV negative or serostatus unknown partners was significantly
associated with greater trauma-related behavioral difficulties, more HIV-related shame, and fewer active coping strategies.
Thus, trauma symptoms, shame, coping style, and substance use were significantly associated with sexual risk behavior among
HIV-positive adults with histories of CSA, with models of prediction differing by gender and partner serostatus. HIV prevention
intervention for persons with HIV and CSA histories should address trauma-related behavioral difficulties and enhance coping
skills to reduce sexual transmission risk behavior. 相似文献
93.
Cook D Douketis J Meade M Guyatt G Zytaruk N Granton J Skrobik Y Albert M Fowler R Hebert P Pagliarello G Friedrich J Freitag A Karachi T Rabbat C Heels-Ansdell D Geerts W Crowther M;Canadian Critical Care Trials Group 《Critical care (London, England)》2008,12(2):R32-9
Background
Critically ill patients with renal insufficiency are predisposed to both deep vein thrombosis (DVT) and bleeding. The objective of the present study was to evaluate the prevalence, incidence and predictors of DVT and the incidence of bleeding in intensive care unit (ICU) patients with estimated creatinine clearance <30 ml/min.Methods
In a multicenter, open-label, prospective cohort study of critically ill patients with severe acute or chronic renal insufficiency or dialysis receiving subcutaneous dalteparin 5,000 IU once daily, we estimated the prevalence of proximal DVT by screening compression venous ultrasound of the lower limbs within 48 hours of ICU admission. DVT incidence was assessed on twice-weekly ultrasound testing. We estimated the incidence of major and minor bleeding by daily clinical assessments. We used Cox proportional hazards regression to identify independent predictors of both DVT and major bleeding.Results
Of 156 patients with a mean (standard deviation) creatinine clearance of 18.9 (6.5) ml/min, 18 had DVT or pulmonary embolism within 48 hours of ICU admission, died or were discharged before ultrasound testing – leaving 138 evaluable patients who received at least one dose of dalteparin. The median duration of dalteparin administration was 7 days (interquartile range, 4 to 12 days). DVT developed in seven patients (5.1%; 95% confidence interval, 2.5 to 10.1). The only independent risk factor for DVT was an elevated baseline Acute Physiology and Chronic Health Evaluation II score (hazard ratio for 10-point increase, 2.25; 95% confidence interval, 1.03 to 4.91). Major bleeding developed in 10 patients (7.2%; 95% confidence interval, 4.0 to 12.8), all with trough anti-activated factor X levels ≤ 0.18 IU/ml. Independent risk factors for major bleeding were aspirin use (hazard ratio, 6.30; 95% confidence interval, 1.35 to 29.4) and a high International Normalized Ratio (hazard ratio for 0.5-unit increase, 1.68; 95% confidence interval, 1.07 to 2.66).Conclusion
In ICU patients with renal insufficiency, the incidence of DVT and major bleeding are considerable but appear related to patient comorbidities rather than to an inadequate or excessive anticoagulant from thromboprophylaxis with dalteparin.Clinical Trial Registration
Number NCT00138099. 相似文献94.
To comprehend a pun involving a homonym (e.g., The prince with a bad tooth got a crown), both meanings of the homonym must be accessed and selected. Previous ERP studies have shown that the N400 reflects lexicosemantic processing, but none have directly investigated the N400 elicited by homonyms in the unique context of puns. Here, N400 priming effects showed that the dual context of puns (e.g., the primes prince and tooth) did not facilitate homonym processing in comparison to single dominant biasing (e.g., The prince with a bad leg got a crown) or subordinate biasing (e.g., The adult with a bad tooth got a crown) conditions. However, homonyms did elicit a less negative N400 (i.e., priming) in the pun condition in comparison to the neutral context condition (e.g., The adult with a bad leg got a crown). These findings are interpreted in terms of the dominant advantage and subordinate bias effect posited by the reordered access model of homonym processing, and in terms of N400 amplitude as an index of how consistently various sources of semantic featural information converge on one lexical item, even when two lexical items must be activated for comprehension. 相似文献
95.
Initial assessment on the impact of crystalloids versus colloids during damage control resuscitation
Chrissy Guidry Elizabeth Gleeson Eric R. Simms Lance Stuke Peter Meade Norman E. McSwain Jr Juan C. Duchesne 《The Journal of surgical research》2013
Background
High ratios of fresh frozen plasma:packed red blood cells in damage control resuscitation (DCR) are associated with increased survival. The impact of volume and type of resuscitative fluid used during high ratio transfusion has not been analyzed. We hypothesize a difference in outcomes based on the type and quantity of resuscitative fluid used in patients that received high ratio DCR.Methods
A matched case control study of patients who received transfusions of ≥ four units of PRBC during damage control surgery over 4 1/2 y, was conducted at a Level I Trauma Center. All patients received a high ratio DCR, >1:2 of fresh frozen plasma:packed red blood cells. Demographics and outcomes of the type and quantity of resuscitative fluids used in combination with high ratio DCR were compared and analyzed. A Kaplan-Meier survival analysis was computed among four groups: colloid (median quantity = 1.0 L), <3 L crystalloid, 3–6 L crystalloid, and >6 L crystalloid.Results
There were 56 patients included in the analysis (28 in the crystalloid group and 28 in the colloid group). Demographics were statistically similar. Intraoperative median units of PRBC: crystalloid versus colloid groups was 13 (IQR 8-21) versus 16 (IQR 12–19), P = 0.135; median units of FFP: 12 (IQR 7–18) versus 12 (IQR 10–18), P = 0.440. OR for 10-d mortality in the crystalloid group was 8.41 [95% CI 1.65–42.76 (P = 0.01)]. Kaplan-Meier survival analysis demonstrated lowest mortality in the colloid group and higher mortality with increasing amounts of crystalloid (P = 0.029).Conclusions
During high ratio DCR, resuscitation with higher volumes of crystalloids was associated with an overall decreased survival, whereas low volumes of colloid use were associated with increased survival. In order to improve outcomes without diluting the survival benefit of hemostatic resuscitation, guidelines should focus on effective low volume resuscitation when high ratio DCR is used. A multi-institutional analysis is needed in order to validate these results. 相似文献96.
Background
There is growing research on student use of podcasts in academic settings. However, there is little in-depth research focusing on student experience of podcasts, in particular in terms of barriers to, and facilitators of, podcast use and students' perceptions of the usefulness of podcasts as learning tools. This study aimed to explore the experiences of non-medical prescribing students who had access to podcasts of key pharmacology lectures as supplementary learning tools to their existing course materials. 相似文献97.
M Bishop W C Shoemaker S Avakian E James G Jackson D Williams P Meade A Fleming 《The American surgeon》1991,57(12):737-746
The objective was to develop a single branched-chain decision tree for both blunt and penetrating thoracic and abdominal trauma and to test its feasibility to track clinical decisions. The algorithm consisted of 14 specific patient management loops and 31 decision nodes. During a 4-month period, the management decisions and clinical course of 434 trauma patients were prospectively observed. Thirty-four patients had no signs of life on arrival to the emergency department (ED) and were excluded from the statistical evaluation; the remaining 400 patients constituted the study group. The mean Injury Severity Score (ISS), Penetrating Abdominal Trauma Index (PATI), and Trauma Score (TS) scores in the series were 21 +/- 10, 34 +/- 12, and 13 +/- 3. The overall patient mortality of the study group was 17 per cent; it was 61 per cent in those patients with major deviations from the algorithm and 6 per cent in patients who complied with the algorithm. The ISS, PATI, and TS scores were 29 +/- 9, 32 +/- 12, and 13 +/- 2 in patients with deviations and 20 +/- 10, 37 +/- 12, and 14 +/- 2 in patients who complied with the algorithm. Of the 37 patients who died with major deviations from the algorithm, the deviation was directly contributory to death in 21 cases (57%) and probably contributory in another 14 cases (38%). There were 108 patients with ISS scores between 20 and 50. In this group, mortality was 55 per cent when a major deviation occurred and 5 per cent without major deviations from the algorithm. The authors conclude that the survival of trauma patients may be improved by following the specific management criteria outlined by the algorithm. 相似文献
98.
Background: Multiple pharmacologic treatments have been studied for patients with acute respiratory distress syndrome (ARDS) and acute lung injury (ALI). Our objective was to systematically evaluate this literature to determine the effects of these interventions on important clinical outcomes. Methods: We searched OVID versions of CENTRAL (The Cochrane Library Issue 3, 2003), MEDLINE (1966-week 2, January 2004), EMBASE (1980-week 4, 2004), CINAHL (1982-week 2, January 2004), and HEALTHSTAR (1995-December 2003); proceedings from four conferences (1994–2003); and bibliographies of review articles and included studies. We included randomized controlled trials (RCTs) of pharmacologic treatments compared with no therapy or placebo for established ARDS and ALI in adults admitted to an intensive care unit, with measurement of early mortality, late mortality, duration of ventilation, ventilator-free days, non-pulmonary organ dysfunction, or adverse events. We excluded trials in other populations incorporating subgroup analyses of patients with ARDS and ALI and studies of nitric oxide, partial liquid ventilation, and fluid and nutritional interventions. Two reviewers independently screened studies and abstracted data from studies included in the analysis. Data were pooled using random effects models where appropriate. Results: We retrieved 75 potentially relevant articles and abstracts, of which 33 trials randomizing 3272 patients met our selection criteria. Meta-analysis showed no effect on early mortality for alprostadil ([prostaglandin E1] seven studies; 693 patients; relative risk [RR] 0.95; 95% confidence interval [CI], 0.77, 1.17), acetylcysteine (five studies; 235 patients; RR 0.89; 95% CI, 0.65, 1.21), early high-dose corticosteroids (two studies; 180 patients; RR 1.12; 95% CI, 0.72, 1.74), or surfactant therapy (nine studies; 1418 patients; RR 0.93; 95% CI, 0.77, 1.12). Most trials of alprostadil, early high-dose corticosteroids, and surfactant therapy showed more adverse events in the active therapy arm. Single small RCTs demonstrated lower hospital mortality (24 patients, RR 0.20; 95% CI, 0.05, 0.81) with corticosteroids for late phase ARDS and lower 1-month mortality (30 patients, RR 0.67; 95% CI, 0.47, 0.95) with pentoxifylline for patients with metastatic cancer and ARDS. Individual trials of nine additional interventions failed to show beneficial effects on prespecified outcomes. Conclusions: Effective pharmacotherapy for ARDS is extremely limited. Corticosteroids for late phase ARDS and pentoxifylline for patients with metastatic cancer and ARDS reduced mortality in single small studies. However, further research is required to investigate their potential benefit in the treatment of ALI/ARDS. 相似文献
99.
Identification of a novel hierarchy of endothelial progenitor cells using human peripheral and umbilical cord blood 总被引:48,自引:5,他引:48
Ingram DA Mead LE Tanaka H Meade V Fenoglio A Mortell K Pollok K Ferkowicz MJ Gilley D Yoder MC 《Blood》2004,104(9):2752-2760
Emerging evidence to support the use of endothelial progenitor cells (EPCs) for angiogenic therapies or as biomarkers to assess cardiovascular disease risk and progression is compelling. However, there is no uniform definition of an EPC, which makes interpretation of these studies difficult. Although hallmarks of stem and progenitor cells are their ability to proliferate and to give rise to functional progeny, EPCs are primarily defined by the expression of cell-surface antigens. Here, using adult peripheral and umbilical cord blood, we describe an approach that identifies a novel hierarchy of EPCs based on their clonogenic and proliferative potential, analogous to the hematopoietic cell system. In fact, some EPCs form replatable colonies when deposited at the single-cell level. Using this approach, we also identify a previously unrecognized population of EPCs in cord blood that can achieve at least 100 population doublings, replate into at least secondary and tertiary colonies, and retain high levels of telomerase activity. Thus, these studies describe a clonogenic method to define a hierarchy of EPCs based on their proliferative potential, and they identify a unique population of high proliferative potential-endothelial colony-forming cells (HPP-ECFCs) in human umbilical cord blood. 相似文献
100.
本文采用前瞻性群体研究旨在确定降压药物的应用与继发Ⅱ型糖尿病的危险之间是否存在独立的相关性。 作者对12 550名(年龄45-64岁)无糖尿病的成年人进行全面健康评价(包括药物的使用及血压测定)。高血压判定标准为收缩压≥140mmH-g(1mmHg=0.1333 kPa)或舒张压≥90mmHg。确定高血压患者3 804例,根据使用降压药物的种类分为血管紧张素转化酶抑制剂(ACEI)162例,β阻滞剂543例,钙拮抗剂96例,噻嗪利尿剂458例,其它单一药物137例,多种药物(≥2种)934例,其余1 474例高血压患者未给予任何抗高血压药物治疗。随访3年及6年后,通过测定空腹血糖浓度[糖尿病判定标准为:空腹血糖≥126m/dl(≥7.0mmol/L)餐后血糖≥200m/dl(≥11.1mmol/L)]评价糖尿病新病例的发生率。 相似文献