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61.
Journal of Thrombosis and Thrombolysis - The optimal management strategy for submassive or intermediate risk pulmonary embolism (IRPE)—anticoagulation alone versus anticoagulation plus...  相似文献   
62.
This research aimed to investigate the changes in ethical issues in everyday clinical practice recognized by critical care nurses during two observation periods. We conducted a retrospective analysis of data obtained by prospective questionnaire surveys of nurses in the intensive care units (ICU) of a tertiary university-affiliated hospital in Seoul, Korea. Data were collected prospectively during two different periods, February 2002-January 2003 (Period 1) and August 2011-July 2012 (Period 2). Significantly fewer cases with ethical issues were reported in Period 2 than in Period 1 (89 cases [2.1%] of 4,291 ICU admissions vs. 51 [0.5%] of 9,302 ICU admissions, respectively; P < 0.001). The highest incidence of cases with identified ethical issues in both Periods occurred in MICU. The major source of ethical issues in Periods 1 and 2 was behavior-related. Among behaviorrelated issues, inappropriate healthcare professional behavior was predominant in both periods and mainly involved resident physicians. Ethical issue numbers regarding end-oflife (EOL) care significantly decreased in the proportion with respect to ethical issues during Period 2 (P = 0.044). In conclusion, the decreased incidence of cases with identified ethical issues in Period 2 might be associated with ethical enhancement related with EOL and improvements in the ICU care environment of the studied hospital. However, behaviorrelated issues involving resident physicians represent a considerable proportion of ethical issues encountered by critical care nurses. A systemic approach to solve behavior-related issues of resident physicians seems to be required to enhance an ethical environment in the studied ICU.

Graphical Abstract

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63.
When achalasia becomes far advanced and leads to esophageal resection, inflammation of the esophageal mucosa is almost universal. The histology of the esophageal mucosa in less advanced cases of achalasia has not been firmly established. We have studied endoscopic biopsies obtained during evaluation of patients with achalasia. Two to four endoscopic biopsies from the lower esophagus of 26 patients with manometrically verified achalasia were mounted on mesh, serially sectioned, stained, coded and interpreted by two independent observers using recognized criteria. The histological findings were correlated with clinical data. Ten of 26 patients had at least one abnormal biopsy. Five of these 10 patients had a previous Heller myotomy; another patient had several pneumatic dilatations, and two other patients had endoscopically proven candida infections. Of the 16 patients with normal histology, four had prolonged stasis, five had heartburn and one patient had both heartburn and stasis. Unless the patient with achalasia has had a Heller myotomy, balloon dilatation, or a candida infection, the esophageal mucosa on biopsy appears to be within normal limits, even in patients with years of esophageal stasis or complaints of heartburn.  相似文献   
64.
Barrett's esophagus (BE), a gastroesophageal reflux associated complication, is defined as the replacement of normal esophageal squamous mucosa by specialized intestinal columnar mucosa with the appearance of goblet cells. The presence of BE is associated with an increased risk of developing esophageal adenocarcinoma (EAC). Although the exposure of gastroduodenal contents to the esophageal mucosa is considered to be an important risk factor for the development of esophagitis, BE and EAC, the mechanisms of reflux esophageal injury are not fully understood. Animal models are now being used extensively to identify the mechanisms of damage and to devise protective and mitigating strategies. Experimental studies on animal models by mimicking the processing of gastroesophageal reflux injury have bloomed during the past decades, however, there is controversy regarding which experimental model for reflux esophagitis, experimental BE and experimental EAC is best. In this review article we aim to clarify the basic understanding of gastroesophageal reflux injury and its complications of BE and EAC, as well as to present current understanding of the reflux experimental models. The animal models of experimental esophageal injury are summarized with focus on the surgical procedures to guide the investigator in choosing or developing a correct animal model in future studies. In addition, our own experimental studies of the animal models are also briefly discussed.  相似文献   
65.
The critical cell signals that trigger cardiac hypertrophy and regulate the transition to heart failure are not known. To determine the role of Gαq-mediated signaling pathways in these events, transgenic mice were constructed that overexpressed wild-type Gαq in the heart using the α-myosin heavy chain promoter. Two-fold overexpression of Gαq showed no detectable effects, whereas 4-fold overexpression resulted in increased heart weight and myocyte size along with marked increases in atrial naturietic factor (≈55-fold), β-myosin heavy chain (≈8-fold), and α-skeletal actin (≈8-fold) expression, and decreased (≈3-fold) β-adrenergic receptor-stimulated adenylyl cyclase activity. All of these signals have been considered markers of hypertrophy or failure in other experimental systems or human heart failure. Echocardiography and in vivo cardiac hemodynamic studies indeed revealed impaired intrinsic contractility manifested as decreased fractional shortening (19 ± 2% vs. 41 ± 3%), dP/dt max, a negative force–frequency response, an altered Starling relationship, and blunted contractile responses to the β-adrenergic agonist dobutamine. At higher levels of Gαq overexpression, frank cardiac decompensation occurred in 3 of 6 animals with development of biventricular failure, pulmonary congestion, and death. The element within the pathway that appeared to be critical for these events was activation of protein kinase C. Interestingly, mitogen-activated protein kinase, which is postulated by some to be important in the hypertrophy program, was not activated. The Gαq overexpressor exhibits a biochemical and physiologic phenotype resembling both the compensated and decompensated phases of human cardiac hypertrophy and suggests a common mechanism for their pathogenesis.  相似文献   
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67.
With an increasing instance of traumatic brain injury and little advancement over recent decades in the rehabilitation of brain injury survivors and their family members, focus has shifted toward the establishment of effective whole‐family resilience promotion interventions. Using the Brain Injury Family Intervention as a model, clinicians constructed two curriculum‐based interventions grounded in resilience theory and drawing from the interdisciplinary approaches of neuropsychology and marriage and family therapy: (a) the Resilience and Adjustment Intervention, for individual survivors of traumatic brain jury, and (b) the Therapeutic Couples Intervention, designed to increase relational satisfaction in couples following a traumatic brain injury. The present study outlines the need for the integration of resilience tenets into rehabilitation techniques, summarizes the empirical justification for the use of an interdisciplinary approach, and offers an overview with implementation specifics regarding these two newly designed interventions.  相似文献   
68.
Evidence suggests that respondent-driven sampling (RDS) is an efficient approach to sampling among varied populations of adult men who have sex with men (MSM) both in the USA and abroad, although no studies have yet evaluated its performance among younger MSM, a population with a steep rise in HIV infection in recent years. Young MSM (YMSM) may differ in terms of their connectedness to other YMSM (e.g., due to evolving sexual identity, internalization of sexual minority stigma, and lack of disclosure to others) and mobility (e.g., due to parental monitoring) which may inhibit the sampling process. The aims of this study were to evaluate the efficiency and effectiveness of RDS-based sampling among young urban MSM and to identify factors associated with recruitment success. We hypothesized that demographic, social, behavioral, and network factors, including racial/ethnic minority status, homelessness (i.e., as an indicator of socioeconomic marginalization), HIV-positive status, substance use problems, gay community connectedness, and network size would be positively related to recruitment productivity, while sexual minority stigmatization, environmental barriers (e.g., parental monitoring), and meeting sex partners on the internet (i.e., virtual venue) would be negatively related to recruitment productivity. Between December 2009 and February 2013, we used RDS to recruit a sample of 450 YMSM, ages 16–20. Findings suggest that the use of RDS for sampling among YMSM is challenging and may not be feasible based on the slow pace of recruitment and low recruitment productivity. A large number of seeds (38 % of the sample, n = 172) had to be added to the sample to maintain a reasonable pace of recruitment, which makes use of the sample for RDS-based population estimates questionable. In addition, the prevalence of short recruitment chains and segmentation in patterns of recruitment by race/ethnicity further hamper the network recruitment process. Thus, RDS was not particularly efficient in terms of the rate of recruitment or effective in generating a representative sample. Hypotheses regarding factors associated with recruitment success were supported for network size and internalized stigma (but not other factors), suggesting that participants with larger network sizes or high levels of internalized stigma may have more and less success recruiting others, respectively.  相似文献   
69.
Megakaryocytic colony formation by progenitor cells of 18 patients with polycythaemia vera, seven with secondary erythrocytosis and four with erythrocytosis of unexplained origin was studied in vitro by the methyl cellulose culture assay. Fourteen of the 18 patients with polycythaemia vera showed spontaneous megakaryocytic colony formation, i.e. colony growth with normal human plasma as the only source of colony stimulation. None of the patients with secondary erythrocytosis or erythrocytosis of unknown origin or of the normal controls grew colonies in the presence of normal human plasma only. When the plasma of a patient with aplastic anaemia was used instead of normal human plasma and phytohaemagglutinin stimulated leucocyte conditioned medium (PHA-LCM) was added to the culture medium, two of the patients with polycythaemia vera and one with secondary erythrocytosis formed slightly increased numbers of megakaryocytic colonies, while the rest of the patients showed normal colony formation. All of the patients with polycythaemia vera but none of those with secondary erythrocytosis or erythrocytosis of unknown origin showed spontaneous erythroid colony growth. The present study shows that most patients with polycythaemia vera form spontaneous megakaryocytic colonies in vitro. This phenomenon has recently also been demonstrated in essential thrombocythaemia and it is apparently analogous to spontaneous erythroid colony growth seen in all myeloproliferative disorders.  相似文献   
70.
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