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91.
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Introduction

Advanced age is thought to be associated with increased mortality in critically ill patients. This report reviews available data on factors that determine outcome, on the value of prognostic models, and on preferences regarding life-sustaining treatments in (very) elderly intensive care unit (ICU) patients.

Methods

We searched the Medline database (January 1966 to January 2005) for English language articles. Selected articles were cross-checked for other relevant publications.

Results

Mortality rates are higher in elderly ICU patients than in younger patients. However, it is not age per se but associated factors, such as severity of illness and premorbid functional status, that appear to be responsible for the poorer prognosis. Patients' preferences regarding life-sustaining treatments are importantly influenced by the likelihood of a beneficial outcome. Commonly used prognostic models have not been calibrated for use in the very elderly. Furthermore, they do not address long-term survival and functional outcome.

Conclusion

We advocate the development of new prognostic models, validated in elderly ICU patients, that predict not only survival but also functional and cognitive status after discharge. Such a model may support informed decision making with respect to patients' preferences.  相似文献   
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BackgroundIt is estimated that one million people infected with HIV initiate anti-retroviral therapy (ART) in resource-constrained countries annually. This occurs against a background of overburdened health workers with limited skills to handle rapidly changing treatment standards and guidelines hence compromising quality of care. Electronic medical record (EMR)-based clinical decision support systems (CDSS) are considered a solution to improve quality of care. Little evidence, however, exists on the effectiveness of EMR-based CDSS on quality of HIV care and treatment in resource-constrained settings.ObjectiveThe aim of this systematic review was to identify original studies on EMR-based CDSS describing process and outcome measures as well as reported barriers to their implementation in resource-constrained settings. We characterized the studies by guideline adherence, data and process, and barriers to CDSS implementation.MethodsTwo reviewers independently assessed original articles from a search of the MEDLINE, EMBASE, CINAHL and Global Health Library databases until January 2012. The included articles were those that evaluated or described the implementation of EMR-based CDSS that were used in HIV care in low-income countries.ResultsA total of 12 studies met the inclusion criteria, 10 of which were conducted in sub-Saharan Africa and 2 in the Caribbean. None of the papers described a strong (randomized controlled) evaluation design. Guideline adherence: One study showed that ordering rates for CD4 tests were significantly higher when reminders were used. Data and process: Studies reported reduction in data errors, reduction in missed appointments, reduction in missed CD4 results and reduction in patient waiting time. Two studies showed a significant increase in time spent by clinicians on direct patient care. Barriers to CDSS implementation: Technical infrastructure problems such as unreliable electric power and erratic Internet connectivity, clinicians’ limited computer skills and failure by providers to comply with the reminders are key impediments to the implementation and effective use of CDSS.ConclusionThe limited number of evaluation studies, the basic and heterogeneous study designs, and varied outcome measures make it difficult to meaningfully conclude on the effectiveness of CDSS on quality of HIV care and treatment in resource-limited settings. High quality evaluation studies are needed. Factors specific to implementation of EMR-based CDSS in resource-limited setting should be addressed before such countries can demonstrate its full benefits. More work needs to be done to overcome the barriers to EMR and CDSS implementation in developing countries such as technical infrastructure and care providers’ computer illiteracy. However, simultaneously evaluating and describing CDSS implementation strategies that work can further guide wise investments in their wider rollout.  相似文献   
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Flow‐spoiled fresh blood imaging, a noncontrast peripheral MR angiography technique, allows the depiction of the entire tree of peripheral arteries by utilizing the signal difference between systolic‐ and diastolic‐triggered data. The image quality of the technique relies on selecting the right triggering delay times and flow‐dependent read‐out spoiler gradient pulses. ECG triggering delays were verified using manual subtraction and automated software. The read‐out spoiler gradients pulses were optimized on volunteers before utilizing the flow‐spoiled fresh blood imaging technique to screen for peripheral arterial disease. Thirteen consecutive patients with suspected peripheral arterial disease underwent both flow‐spoiled fresh blood imaging and 16‐detector‐row computed tomography angiography examinations. A total of 23 segments were evaluated in the arterial vascular system. Using computed tomography angiography as the reference standard, 56 diseased segments were detected with 22 nonsignificant stenoses (<50%) and 34 significant stenoses, 15 of which were totally occluded. Flow‐spoiled fresh blood imaging had a sensitivity of 97%, a specificity of 96%, an accuracy of 96%, a positive predictive value of 88%, and a negative predictive value of 99%. With such a high negative predictive value, flow‐spoiled fresh blood imaging has the potential to become the safest noninvasive screening tool for peripheral arterial disease, especially for patients with impaired renal function. Magn Reson Med, 2011. © 2010 Wiley‐Liss, Inc.  相似文献   
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Data mining is the process of selecting, exploring, and modeling large amounts of data to discover unknown patterns or relationships useful to the data analyst. This article describes applications of data mining for the analysis of blood glucose and diabetes mellitus data. The diabetes management context is particularly well suited to a data mining approach. The availability of electronic health records and monitoring facilities, including telemedicine programs, is leading to accumulating huge data sets that are accessible to physicians, practitioners, and health care decision makers. Moreover, because diabetes is a lifelong disease, even data available for an individual patient may be massive and difficult to interpret. Finally, the capability of interpreting blood glucose readings is important not only in diabetes monitoring but also when monitoring patients in intensive care units. This article describes and illustrates work that has been carried out in our institutions in two areas in which data mining has a significant potential utility to researchers and clinical practitioners: analysis of (i) blood glucose home monitoring data of diabetes mellitus patients and (ii) blood glucose monitoring data from hospitalized intensive care unit patients.  相似文献   
98.
Background: Although dental implants have a high success rate, failure owing to the absence of adhesion between the gingival connective tissue and the implant surface is still being reported. Purpose: This study was designed to evaluate the effect of a titanium surface charge on fibroblast adhesion. Material and Methods: An electrical chamber was custom‐made to generate negative and positive surface charges on commercially pure titanium cylinders with a potential difference of 4.5 V. Twenty‐seven titanium cylinders were divided into three experimental groups. In each group, cell attachment to a positively charged titanium cylinder, a negatively charged titanium cylinder, and a titanium cylinder (control) was studied at three time intervals of 15, 30, and 60 minutes. NCTC clone 929 fibroblasts were used in these experiments. The effect of the potential difference in the pH of Dulbecco's Modified Eagle Medium (DMEM) was also evaluated using two new specimens at time intervals of 15, 30, 60, and 80 minutes. Results: The fibroblast cell attachment was more statistically significant to the positively charged titanium cylinder than the negatively charged titanium cylinder (p =.002) and the control (p=.000), whereas the cell adhesion difference between the control and the negatively charged titanium cylinder was not statistically significant (p=.808). The range of pH difference of the DMEM in the negative and positive parts of the electrical chamber was 0.46 and 0.30, respectively. Conclusion: Within the limitations of this in vitro study, the positive surface charge of the titanium cylinder results in significantly favorable cell adhesion.  相似文献   
99.
Purpose This in vitro study investigated the effect of lateral cyclic loading with different load positions and periods on abutment rotational displacement (RD) of external hexagon implant system. Materials and Methods Four groups of five implant assemblies each were used. Each assembly consisted of Brånemark System® Mk IV implant (Nobel Biocare AB, Göteborg, Sweden), CeraOne® abutment (Nobel Biocare AB), and a cement‐retained casting. A cyclic load of 50 N was applied centrally and perpendicular to the long axis of the implant for groups A and B for 0.25 and 0.50 × 106 cycles, respectively, while for groups C and D, the same load was applied at 4‐mm distance eccentrically for 0.25 and 0.50 × 106 cycles, respectively. The displacement was evaluated by hand drawing a longitudinal line across the implant‐abutment interface. Before and after loading, the lateral distance between two reference points on the abutment and implant was measured under high resolution (×200) and the difference formed the RD value. The data were analyzed with one‐way analysis of variance and compared with Tukey test (α=0.05). Results Group D had the highest mean of RD value (55.00 ± 1.871 μm), while group A had the lowest (2.800 ± 0.837 μm). Groups A and B had a high statistically significant difference in RD values, as compared to groups C or D (p < .001). Moreover, group C had statistically significant difference from group D (p=.011). Conversely, no statistical significance was obtained when group A was compared with group B. Conclusion Within the limits of this in vitro study, the RD of the external hexagon joint components occurred significantly under eccentric lateral loading when compared to centric loading. The displacement increased significantly with longer period of eccentric lateral loading.  相似文献   
100.
PURPOSE: The Mediterranean diet has been reported to reduce cardiovascular mortality and morbidity considerably. Tomatoes and lycopene are considered potent antioxidants. Our purpose was to study the effects of a tomatoe-rich diet on the lipid profile following 300g daily of tomatoes for one month. METHODS: Plasma concentrations of triglyceride, total cholesterol, HDL-cholesterol, LDL-cholesterol and VLDL-cholesterol were determined in 98 apparently healthy volunteers (mean age 45.5+/-14.1 yr) before and after one month of follow-up. Fifty volunteers (34 women and 16 men) ate tomatoes 300g daily and 48 volunteers (32 women and 16 men) continued their regular diet without eating tomatoes for a month. RESULTS: In the regular diet group, there were no changes in the lipid profile: triglyceride level (169.6+/-156.8 vs. 147.6+/-93.4mg/dl; P=0.33), total cholesterol level (198.3+/-41.2mg/dl vs. 204.2+/-70.9mg/dl; P=0.23), HDL-cholesterol level (50.6+/-12.2mg/dl vs. 47.6+/-10.8mg/dl; P=0.79), and LDL-cholesterol level (122.7+/-39.4mg/dl vs. 120.2+/-32.2mg/dl; P=0.24) before and after the 1 month offollow-up. In the tomato-rich diet group: triglyceride level 170.8+/-85.4mg/dl to 167.4+/-99.4mg/ dl (P=0.98), total cholesterol level 207.5+/-44.3mg/ dl to 204.1+/-45.1mg/dl (P=0.68), HDL-cholesterol level 46.1+/-10.6mg/dl to 53.4+/-13.3mg/dl (P=0.03), and LDL-cholesterol level 127.7+/-41.8mg/dl to 119.1+/-41.7mg/dl (P=0.57). CONCLUSION: We found that tomatoes'-rich diet (300g daily for one month) increased HDL-cholesterol level significantly by 15.2%.  相似文献   
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