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951.
The assessment of severity. Severity assessment is a key element in the management of community-acquired pneumonia. This assessment will determine the level of diagnostic workup and treatment, as well as the site of care. Several tools have been developed to help this assessment. The Pneumonia Severity Index (PSI) or the CURB-65 can accurately identify patients with a low risk of death who might be considered for outpatient care while those with a high risk of death would be hospitalized. Nevertheless, PSI and CURB-65 are less accurate for identifying patients requiring admission to an intensive care unit (ICU). Different scores, such the American Thoracic Society criteria or the SMART-COP score, were built to predict need for admission to ICU, vasopressors or mechanical ventilation. Each score has its own strengths and weaknesses and physicians must be aware of these limitations. Although, severity assessment tools are useful guides in the management of patients with community acquired pneumonia, clinical judgment must remain decisive. 相似文献
952.
LD Rasmussen M Dybdal J Gerstoft G Kronborg CS Larsen C Pedersen G Pedersen J Jensen L Pedersen HT Sørensen N Obel 《HIV medicine》2011,12(4):202-210
Objective
The association between HIV infection and the risk of venous thromboembolism (VTE) is controversial. We examined the risk of VTE in HIV‐infected individuals compared with the general population and estimated the impact of low CD4 cell count, highly active antiretroviral therapy (HAART) and injecting drug use (IDU).Methods
We identified 4333 Danish HIV‐infected patients from the Danish HIV Cohort Study and a population‐based age‐ and gender‐matched comparison cohort of 43 330 individuals. VTE diagnoses were extracted from the Danish National Hospital Registry. Cumulative incidence curves were constructed for time to first VTE. Incidence rate ratios (IRRs) and impact of low CD4 cell count and HAART were estimated by Cox regression analyses. Analyses were stratified by IDU, adjusted for comorbidity and disaggregated by overall, provoked and unprovoked VTE.Results
The 5‐year risk of VTE was 8.0% [95% confidence interval (CI) 5.78–10.74%] in IDU HIV‐infected patients, 1.5% (95% CI 1.14–1.95%) in non‐IDU HIV‐infected patients and 0.3% (95% CI 0.29–0.41%) in the population comparison cohort. In non‐IDU HIV‐infected patients, adjusted IRRs for unprovoked and provoked VTE were 3.42 (95% CI 2.58–4.54) and 5.51 (95% CI 3.29–9.23), respectively, compared with the population comparison cohort. In IDU HIV‐infected patients, the adjusted IRRs were 12.66 (95% CI 6.03–26.59) for unprovoked VTE and 9.38 (95% CI 1.61–54.50) for provoked VTE. Low CD4 cell count had a minor impact on these risk estimates, while HAART increased the overall risk (IRR 1.93; 95% CI 1.00–3.72).Conclusion
HIV‐infected patients are at increased risk of VTE, especially in the IDU population. HAART and possibly low CD4 cell count further increase the risk. 相似文献953.
Novel cytochrome P450-2D6 promoter sequence variations in hepatitis C positive and negative subjects
Introduction. CYP2D6 is a liver enzyme that metabolizes more that 25% of drugs and thus may play a pivotal role in drug-drug interactions. The promoter sequences of cytochrome P450 2D6 (CYP2D6) gene could impact metabolic activity.Methods. We analyzed genetic variations in the promoter sequence of CYP2D6 gene for 71 hepatitis C negative and 15 hepatitis C positive subjects.Results. We found two novel genetic variants -1822A→G; -1740C→T, only in two patients with hepatitis C. Also, two linked new promoter sequence variations at -2060 G→A and -2053 T→G nucleotide positions that present in both hepatitis C negative and positive subjects are identified. The -2060 and -2053 variations are confirmed to be in linkage disequilibrium. The individuals with -2060A/A, and -2053G/G variation appeared to be associated with significantly lower levels of liver CYP2D6 mRNA. Analysis of CYP2D6 enzymatic activity in *1/*1 (wild type) subjects revealed that hepatitis C positive subjects expressed about 2.6-fold lower activity (24.0 ± 1.5 vs. 62.6 ± 3.7 pmol/min/mg; p = 0.0061) relative to hepatitis C negative.Conclusion. These data suggest that promoter variations -1822A→G and -1740C→T are present only in hepatitis C infected subjects. Hepatitis C positive individuals were associated with a lower liver CYP2D6 enzyme activity. 相似文献
954.
Ron C. Gaba Patrick M. Couture James T. Bui M. Grace Knuttinen Natasha M. Walzer Eric R. Kallwitz Jamie L. Berkes Scott J. Cotler 《Journal of vascular and interventional radiology : JVIR》2013,24(3):411-420.e4
PurposeTo compare the performance of various liver disease scoring systems in predicting early mortality after transjugular intrahepatic portosystemic shunt (TIPS) creation.Materials and MethodsIn this single-institution retrospective study, eight scoring systems were used to grade liver disease in 211 patients (male-to-female ratio = 131:80; mean age, 54 y) before TIPS creation from 1999–2011. Scoring systems included bilirubin level, Child-Pugh (CP) score, Model for End-Stage Liver Disease (MELD) and Model for End-Stage Liver Disease sodium (MELD-Na) score, Emory score, prognostic index (PI), Acute Physiology and Chronic Health Evaluation (APACHE) 2 score, and Bonn TIPS early mortality (BOTEM) score. Medical record review was used to identify 30-day and 90-day clinical outcomes. The relationship of scoring parameters with mortality outcomes was assessed with multivariate analysis, and the relative ability of systems to predict mortality after TIPS creation was evaluated by comparing area under receiver operating characteristic (AUROC) curves.ResultsTIPS were successfully created for variceal hemorrhage (n = 121), ascites (n = 72), hepatic hydrothorax (n = 15), and portal vein thrombosis (n = 3). All scoring systems had a significant association with 30-day and 90-day mortality (P<.050 in each case) on multivariate analysis. Based on 30-day and 90-day AUROC, MELD (0.878, 0.816) and MELD-Na (0.863, 0.823) scores had the best capability to predict early mortality compared with bilirubin (0.786, 0.749), CP (0.822, 0.771), Emory (0.786, 0.681), PI (0.854, 0.760), APACHE 2 (0.836, 0.735), and BOTEM (0.798, 0.698), with statistical superiority over bilirubin, Emory, and BOTEM scores.ConclusionsSeveral liver disease scoring systems have prognostic value for early mortality after TIPS creation. MELD and MELD-Na scores most effectively predict survival after TIPS creation. 相似文献
955.
Rosana E. Norman Theo Vos Jan J. Barendregt Bui Ngoc Linh Nguyen Thanh Huong Hideki Higashi Emily Carnahan Alan D. Lopez 《Preventive medicine》2013
Objective
Smoking prevalence among Vietnamese men is among the highest in the world. Our aim was to provide estimates of tobacco attributable mortality to support tobacco control policies.Method
We used the Peto–Lopez method using lung cancer mortality to derive a Smoking Impact Ratio (SIR) as a marker of cumulative exposure to smoking. SIRs were applied to relative risks from the Cancer Prevention Study, Phase II. Prevalence-based and hybrid methods, using the SIR for cancers and chronic obstructive pulmonary disease and smoking prevalence for all other outcomes, were used in sensitivity analyses.Results
When lung cancer was used to measure cumulative smoking exposure, 28% (95% uncertainty interval 24–31%) of all adult male deaths (> 35 years) in Vietnam in 2008 were attributable to smoking. Lower estimates resulted from prevalence-based methods [24% (95% uncertainty interval 21–26%)] with the hybrid method yielding intermediate estimates [26% (95% uncertainty interval 23–28%)].Conclusion
Despite uncertainty in these estimates of attributable mortality, tobacco smoking is already a major risk factor for death in Vietnamese men. Given the high current prevalence of smoking, this has important implications not only for preventing the uptake of tobacco but also for immediate action to adopt and enforce stronger tobacco control measures. 相似文献956.
957.
Pre-implantation genetic diagnosis is an alternative to prenatal diagnosis for a select group of patients. Patients have to go through in vitro fertilization in order to produce embryos in vitro, from which one or two cells are removed at the 8-cell stage. A fluorescence in situ hybridization or polymerase chain reaction is carried out for the genetic diagnosis. Fluorescence in situ hybridization is used for the analysis of chromosomes for sexing for X-linked disease, chromosome abnormalities and aneuploidy screening. Aneuploidy screening is performed for infertile patients going through in vitro fertilization to try to improve their pregnancy rate. A polymerase chain reaction is used for the diagnosis of single-gene disorders. Since the risk of contamination and allele dropout is high with a polymerase chain reaction, linked or unlinked markers are usually used in a fluorescent multiplex polymerase chain reaction. New techniques, for example comparative genomic hybridization, allow the analysis of all of the chromosomes from one cell at one time. The ethical implications of pre-implantation genetic diagnosis are immense as the technique has already been used for social sexing and human leukocyte antigen matching. 相似文献
958.
Future directions 总被引:5,自引:0,他引:5
Evans MI Wapner RJ Bui TH 《Best practice & research. Clinical obstetrics & gynaecology》2002,16(5):757-759
959.
Nelson EL Bui TN Velasquez SE 《Child and adolescent psychiatric clinics of North America》2011,20(1):67-79
There are significant workforce shortages for psychologists with expertise in evidence-supported therapies with children, particularly in nonmetropolitan areas. Telepsychology, or psychology services delivered by real-time videoconferencing, helps bridge this access gap. This article first reviews the telepsychology literature and then builds on early telepsychology guidance for the current practice environment. The practicalities of telepsychology implementation and the lessons drawn from the more well-established telepsychiatry practice are described. The authors also provide an update to pioneering interdisciplinary telehealth principles presented a decade ago. 相似文献
960.