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51.
52.
Journal of Thrombosis and Thrombolysis - Newer generation durable polymer drug-eluting stents (DP-DES) and biodegradable polymer DES (BP-DES) have similar efficacy with dual-antiplatelet therapy...  相似文献   
53.
54.
The platelet integrin alphaIIbbeta3 alters conformation in response to platelet activation and ligand binding, although the molecular mechanisms involved are not known. We previously showed that a lipid modified peptide, corresponding to the membrane proximal 989KVGFFKR995 portion of the alphaIIb cytoplasmic tail, independently activates platelet alphaIIbbeta3. Calreticulin (CRT) is a potential integrin regulatory protein based on its interaction with the highly conserved alpha-integrin sequence KxGFFKR. We therefore examined the possible interaction of calreticulin and alphaIIbbeta3 in human platelets. We demonstrate that calreticulin in platelets is localised to the granulomere. In contrast, the known integrin-binding protein talin accumulates at the periphery of spreading platelets and colocalises with alphaIIbbeta3 during the process of adhesion. An interaction between calreticulin and alphaIIbbeta3 could not be demonstrated using co-immunoprecipitation techniques under various platelet activation states, even in the presence of covalent chemical crosslinkers. Thus, calreticulin does not functionally interact with the major integrin in human platelets. In order to identify proteins that interact with the integrin KVGFFKR motif we then used a peptide 'pull-down' assay from platelet lysates with biotinylated peptides and demonstrate that only the alphaIIb and beta3 subunits selectively and individually interact with this sequence. This interaction is divalent cation-dependent, has high-affinity, and occurs both with purified alphaIIbbeta3 complex and with electroeluted alpha and beta subunits. Thus, our data show that the conserved integrin KVGFFKR domain interacts primarily with the alpha and beta cytoplasmic tails and not with CRT in human platelets.  相似文献   
55.
Initial evaluation of 22 patients with cystic fibrosis (CF) on entry into a trial of home oxygen therapy was used to elucidate the possible effects of poor nutritional status on exercise performance in CF. The patients had advanced lung disease (mean FEV1, 36 percent predicted) and all had a stable resting PaO2 less than or equal to 65 mm Hg. Nutritional status was determined by calculating weight as a percentage of ideal for height (Wt/Ht) for each subject. Exercise testing consisted of a progressive exercise test on a cycle ergometer to measure maximum work capacity (Wmax), and a steady state test at 50 percent of baseline Wmax. During the steady state test, cardiac output (Q) and stroke volume (SV) were computed by the indirect Fick (CO2) method. Wmax, SV, Q and lung function results are expressed as percent predicted. Mean (+/- SD) Wmax was 58 +/- 15 percent predicted. Wmax correlated with both FEV1 and Wt/Ht, but FEV1 and Wt/Ht were not related. During steady state exercise, 12 of 22 patients had a SV less than 80 percent predicted. SV correlated with Wt/Ht, but not with lung function. Thirteen of the 22 patients had a Wt/Ht less than or equal to 90 percent and were considered malnourished. When compared with the well-nourished patients (Wt/Ht greater than 90%), these malnourished subjects had significantly lower mean values for Wmax%, SV% and Q% predicted, but not for lung function parameters. We conclude that: in patients with CF and advanced lung disease, nutritional status plays a significant role in determining exercise capacity; lower exercise tolerance of malnourished patients is an independent effect, as nutritional status and lung function were not related; and malnourished patients with CF have an altered cardiac performance on exercise testing which is due to a reduced SV rather than an impaired heart rate response.  相似文献   
56.
Abstract

Assistive technology (AT) is a powerful enabler of participation. The World Health Organization’s Global Collaboration on Assistive Technology (GATE) programme is actively working towards access to assistive technology for all. Developed through collaborative work as a part of the Global Research, Innovation and Education on Assistive Technology (GREAT) Summit, this position paper provides a “state of the science” view of AT users, conceptualized as “People” within the set of GATE strategic “P”s. People are at the core of policy, products, personnel and provision. AT is an interface between the person and the life they would like to lead. People’s preferences, perspectives and goals are fundamental to defining and determining the success of AT. Maximizing the impact of AT in enabling participation requires an individualized and holistic understanding of the value and meaning of AT for the individual, taking a universal model perspective, focusing on the person, in context, and then considering the condition and/or the technology. This paper aims to situate and emphasize people at the centre of AT systems: we highlight personal meanings and perspectives on AT use and consider the role of advocacy, empowerment and co-design in developing and driving AT processes.  相似文献   
57.
Objectives: Paramedics' decision to terminate field resuscitation without a physician present may depend on personal and external factors. This study investigates factors associated with paramedic psychological comfort with termination of resuscitation (TOR) to inform future training. Methods: We administered an anonymous survey to all practicing paramedics in a large urban Asian Emergency Medical Services system where formal TOR training had not yet been conducted and field TOR was not routinely applied. The survey assessed psychological comfort using the validated Psychological Comfort Total (PCT) scale (summed score of 28 items, with higher scores representing greater comfort). We examined scores associated with four personal (prior resolution of personal loss, knowledge of survival probability, religious affiliation and experience with death pronouncements) and two external (location of patient and perceived trust of family) factors. Data were entered into Excel and analyzed by t-tests and ANOVA. Results: Response rate was 73.6% (254/345). Respondents were 30.3 years (mean, SD 7.1) with 7.2 years (mean, SD 5.54) of practice experience. Over 60% had been involved in 6 or more field death pronouncements in the prior 12 months. Higher PCT scores were associated with prior resolution of personal loss and knowledge of survival probability. Lower PCT scores were associated with patient location in a public place and perceived family lack of trust. PCT scores were not associated with paramedic religious affiliation or number of prior death pronouncements. Conclusions: Paramedic psychological comfort with field death pronouncement is associated with personal and external factors. Since paramedic comfort is important for protocol adoption, TOR education should target not only knowledge, but also public arena management, communication skills for engaging with families, and help paramedics resolve prior personal loss.  相似文献   
58.

Objective

To determine adverse event rates for adult cranial neuro-oncologic surgeries performed at a high-volume quaternary academic center and assess the impact of resident participation on perioperative complication rates.

Patients and Methods

All adult patients undergoing neurosurgical intervention for an intracranial neoplastic lesion between January 1, 2009, and December 31, 2013, were included. Cases were categorized as biopsy, extra-axial/skull base, intra-axial, or transsphenoidal. Complications were categorized as neurologic, medical, wound, mortality, or none and compared for patients managed by a chief resident vs a consultant neurosurgeon.

Results

A total of 6277 neurosurgical procedures for intracranial neoplasms were performed. After excluding radiosurgical procedures and pediatric patients, 4151 adult patients who underwent 4423 procedures were available for analysis. Complications were infrequent, with overall rates of 9.8% (435 of 4423 procedures), 1.7% (73 of 4423), and 1.4% (63 of 4423) for neurologic, medical, and wound complications, respectively. The rate of perioperative mortality was 0.3% (14 of 4423 procedures). Case performance and management by a chief resident did not negatively impact outcome.

Conclusion

In our large-volume brain tumor practice, rates of complications were low, and management of cases by chief residents in a semiautonomous manner did not negatively impact surgical outcomes.  相似文献   
59.
BACKGROUND: Traditionally, ERCP has been the only reliable method for imaging the biliary tree, but it is invasive and carries a risk of complications. Magnetic resonance cholangiopancreatography (MRCP) is a noninvasive method for imaging the biliary tree. The aim of this study was to prospectively assess the accuracy of MRCP in a large number of patients. METHODS: Consecutive patients referred to a teaching hospital for ERCP were eligible for study entry. MRCP was performed within 24 hours before ERCP. MRCP findings were compared with ERCP findings or, when the initial ERCP was unsuccessful, with results of repeat ERCP, percutaneous transhepatic cholangiography, or surgery. RESULTS: One hundred forty-six patients underwent 149 ERCP/MRCP procedures, of which 129 were evaluable with successful MRCP and ERCP or an ERCP-equivalent study. Diagnoses included choledocholithiasis in 46 and biliary stricture in 12 patients. The sensitivity, specificity, positive, and negative predictive values for MRCP in the diagnosis of choledocholithiasis were 97.9%, 89.0%, 83.6%, and 98.6%, respectively. All 12 strictures were diagnosed by MRCP (sensitivity 100%, specificity 99.1%). CONCLUSIONS: MRCP is an accurate, noninvasive alternative to ERCP for imaging the biliary tree. Choledocholithiasis and biliary strictures can be reliably diagnosed or excluded by MRCP. MRCP should be used increasingly in patients with suspected biliary obstruction to select those who require a therapeutic procedure.  相似文献   
60.

Introduction

Surgical site infection (SSI) is an infection occurring in an incisional wound within 30 days of surgery and significantly affects patients undergoing colorectal surgery. This study examined a multi-institutional dataset to determine risk factors for SSI following colorectal resection.

Methods

Data on 386 patients who underwent colorectal resection in three institutions were accrued. Patients were identified using a prospective SSI database and hospital records. Data are presented as median (interquartile range), and logistic regression analysis was used to identify risk factors.

Results

Patients (21.5 %) developed a postoperative SSI. The median time to the development of SSI was 7 days (5–10). Of all infections, 67.5 % were superficial, 22.9 % were deep and 9.6 % were organ space. In univariate analysis, an ASA grade of II (RR 0.6, CI 0.3–0.9, P?=?0.019), having an elective procedure (RR 0.4, CI 0.2–0.6, P?<?0.001), using a laparoscopic approach (RR 0.5, CI 0.3–0.9, P?=?0.019), having a daytime procedure (RR 0.3, CI 0.1–0.7, P?=?0.006) and having a clean/contaminated wound (RR 0.4, CI 0.2–0.7, P?=?0.001) were associated with reduced risk of SSI. In multivariate analysis, an ASA grade of IV (RR 3.9, CI 1.1–13.7, P?=?0.034), a procedure duration over 3 h (RR 4.3, CI 2.3–8.2, P?<?0.001) and undergoing a panproctocolectomy (RR 6.5, CI 1.0–40.9, P?=?0.044) were independent risk factors for SSI. Those who developed an SSI had a longer duration of inpatient stay (22 days [16–31] vs 15 days [10–26], P?<?0.001).

Conclusions

Patients who develop an SSI have a longer duration of inpatient stay. Independent risk factors for SSI following colorectal resection include being ASA grade IV, having a procedure duration over 3 h, and undergoing a panproctocolectomy.
  相似文献   
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