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941.
We present a patient with metastatic pheochromocytoma, who developed progressive and fatal hypoglycemia most likely secondary to direct tumor glucose consumption that did not respond to high-dose glucose infusion, corticosteroids, or glucagon therapy. The pattern of glucose uptake on (18)F-2-fluoro-2-deoxy-D-glucose positron emission tomography, with preferential tumor glucose uptake in association with a marked reduction in normal uptake in the heart, muscles, and brain, is highly suggestive of direct consumption of glucose by the tumor rather than insulin-like growth factor-2 mediated hypoglycemia. In patients with large-volume metastatic malignancies, direct tumor glucose consumption should be considered in the differential diagnosis of hypoglycemia. Nuclear medicine imaging techniques can illustrate the pathophysiology of hypoglycemia in such cases.  相似文献   
942.
943.
Early and accurate diagnosis and treatment of rheumatoid arthritis (RA) improves disease outcome. Anti-cyclic citrullinated peptide antibody (anti-CCP) which is highly specific for RA is produced locally from inflamed synovium. The present study was designed to assess the diagnostic performance of synovial fluid anti-CCP (sf-CCP) for RA. A total of 128 patients consisted of 37 RA confirmed by the American College of Rheumatology revised criteria, 91 non-RA (50 non-RA inflammatory arthritis and 41 osteoarthritis) entered the study. Serum anti-CCP (sm-CCP) and Sf-CCP were measured by the ELISA method. Receiver operating characteristics curves were constructed to determine the optimal cutoff point levels for sf-CCP and sm-CCP to discriminate RA from non-RA. Diagnostic characteristics of both variables were determined by comparison of RA patients with non-RA controls. Mean levels of sf-CCP and sm-CCP were significantly higher in RA than in non-RA (P < 0.001). Sf-CCP discriminated RA from non-RA at the optimal cutoff value of 10 U/mL with high accuracy at AUC value of 0.897 ± 0.039, P < 0.001) sensitivity of 83.7% and specificity of 95.6%. Sm-CCP diagnosed RA at optimal cutoff level of 14.6 U/mL with respective sensitivity, specificity and AUC values of 84.8, 94.3% and 0.895 ± 0.049, P < 0.001). Sm-CCP was strongly correlated with sf-CCP (r = 0.75, r 2 = 0.57, P < 0.0001). Two of 5 sm-CCP negative RA and 25.7% of serum rheumatoid factors negative RA were sf-CCP positive. These findings indicate that sf-CCP yields diagnostic ability as comparable as sm-CCP for RA. Respecting to local production of sf-CCP prior to disease onset, therefore sf-CCP determination may offer earlier as well as additional diagnostic information which may be more helpful in recognizing RA particularly among recent onset arthritis.  相似文献   
944.
Heart failure (HF) may contribute to the development of functional decline and frailty in older adults. Sixty HF patients with an ejection fraction ≤ 40% evaluated in 2004 and 2005 were reevaluated in 2008. Six-minute walk distance (6MW), frailty score, and biomarkers (25-hydroxyvitamin D, C-reactive protein, and interleukin-6 [IL-6]) were measured. Participants were categorized at baseline and follow-up into 3 groups: nonfrail/normal endurance (NF/NE), nonfrail/low endurance (NF/LE) and frail/low endurance (F/LE). Survival time was assessed according to frailty/endurance status and associated predictors of mortality. Forty-three men, 17 women (mean age, 78 ± 12 years) were contacted. At follow-up, 20 had died, 20 participated, and 20 did not participate. There were no changes in frailty/endurance status over time (McNemar;P=.19). Deaths occurred in 18% of NF/NE, 45% of NF/LE, and 60% of F/LE persons. The NF/NE group had greater survival rates than the NF/LE ( P=.032) and F/LE ( P=.014) groups. The 6MW and frailty score were independently predictive of mortality, with hazard ratios of 0.82 (95% confidence interval, 0.72-0.94) and 1.64 (95% confidence interval, 1.19-2.26), respectively, as was New York Heart Association class and IL-6. Backward stepwise Cox regression revealed that 6MW and frailty each were associated with mortality (P=.005) and highly correlated. Physical function is an important predictor of mortality in older adults with HF. The 6MW may be useful as a measure of frailty.  相似文献   
945.
A novel microcapsule adsorbent for separation of uranium from phosphoric acid solutions was developed by immobilizing the di(2-ethylhexyl) phosphoric acid-trioctyl phosphine oxide extractants in the polymeric matrix of calcium alginate. Physical characterization of the microcapsules was accomplished by scanning electron microscopy and thermogravimetric techniques. Equilibrium experiments revealed that both ion exchange and solvent extraction mechanisms were involved in the adsorption of [Formula: see text] ions, but the latter prevailed in a wider range of acid concentration. According to the results of kinetics study, at low acidity level, the rate controlling step was slow chemical reaction of [Formula: see text] ions with the microdroplets of extractant, whereas it changed to intraparticle diffusion at higher acid concentration. The study also attempted identification of the diffusion paths of the ions within the microcapsules, and the mechanism of change of mass transfer rate during the uptake process. The prepared microcapsules preserved their entire capacity after three cycles of adsorption, and their breakthrough behaviour was well fitted by a new formula derived from shrinking core model.  相似文献   
946.
Clozapine has superior efficacy for treating patients with schizophrenia. Its discontinuation could have detrimental consequences. We attempted to identify the clinical parameters that could predict clozapine discontinuation in patients diagnosed as having schizophrenia by conducting a retrospective analysis of all of those who started on clozapine treatment during their hospitalization in our institution between 2002 and 2008 (n=100). Demographic and clinical parameters were analyzed and compared between the 58 patients who continued and the 42 who discontinued clozapine treatment during a follow-up period of 8.1 years. Twenty of the latter patients (47.6%) discontinued clozapine because of nonadherence and 11 (26.2%) because of side effects. Thirty-three of them (78.6%) stopped taking clozapine during the first year of treatment. The duration of clozapine use correlated significantly with the time to readmission (P<0.001). The decrease in number of suicide attempts was higher in those who continued clozapine treatment compared with those who discontinued it (P=0.02). Predictors for drug discontinuation were old age at clozapine initiation and comorbid substance abuse. These findings indicate that patients with schizophrenia with those risk factors need special incentives to be compliant during the first year of clozapine treatment to minimize the negative sequelae of clozapine discontinuation.  相似文献   
947.

Background

The spectrum of disorders of the brain is large, covering hundreds of disorders that are listed in either the mental or neurological disorder chapters of the established international diagnostic classification systems. These disorders have a high prevalence as well as short- and long-term impairments and disabilities. Therefore they are an emotional, financial and social burden to the patients, their families and their social network. In a 2005 landmark study, we estimated for the first time the annual cost of 12 major groups of disorders of the brain in Europe and gave a conservative estimate of €386 billion for the year 2004. This estimate was limited in scope and conservative due to the lack of sufficiently comprehensive epidemiological and/or economic data on several important diagnostic groups. We are now in a position to substantially improve and revise the 2004 estimates. In the present report we cover 19 major groups of disorders, 7 more than previously, of an increased range of age groups and more cost items. We therefore present much improved cost estimates. Our revised estimates also now include the new EU member states, and hence a population of 514 million people.

Aims

To estimate the number of persons with defined disorders of the brain in Europe in 2010, the total cost per person related to each disease in terms of direct and indirect costs, and an estimate of the total cost per disorder and country.

Methods

The best available estimates of the prevalence and cost per person for 19 groups of disorders of the brain (covering well over 100 specific disorders) were identified via a systematic review of the published literature. Together with the twelve disorders included in 2004, the following range of mental and neurologic groups of disorders is covered: addictive disorders, affective disorders, anxiety disorders, brain tumor, childhood and adolescent disorders (developmental disorders), dementia, eating disorders, epilepsy, mental retardation, migraine, multiple sclerosis, neuromuscular disorders, Parkinson's disease, personality disorders, psychotic disorders, sleep disorders, somatoform disorders, stroke, and traumatic brain injury. Epidemiologic panels were charged to complete the literature review for each disorder in order to estimate the 12-month prevalence, and health economic panels were charged to estimate best cost-estimates. A cost model was developed to combine the epidemiologic and economic data and estimate the total cost of each disorder in each of 30 European countries (EU27 + Iceland, Norway and Switzerland). The cost model was populated with national statistics from Eurostat to adjust all costs to 2010 values, converting all local currencies to Euro, imputing costs for countries where no data were available, and aggregating country estimates to purchasing power parity adjusted estimates for the total cost of disorders of the brain in Europe 2010.

Results

The total cost of disorders of the brain was estimated at €798 billion in 2010. Direct costs constitute the majority of costs (37% direct healthcare costs and 23% direct non-medical costs) whereas the remaining 40% were indirect costs associated with patients' production losses. On average, the estimated cost per person with a disorder of the brain in Europe ranged between €285 for headache and €30,000 for neuromuscular disorders. The European per capita cost of disorders of the brain was €1550 on average but varied by country. The cost (in billion €PPP 2010) of the disorders of the brain included in this study was as follows: addiction: €65.7; anxiety disorders: €74.4; brain tumor: €5.2; child/adolescent disorders: €21.3; dementia: €105.2; eating disorders: €0.8; epilepsy: €13.8; headache: €43.5; mental retardation: €43.3; mood disorders: €113.4; multiple sclerosis: €14.6; neuromuscular disorders: €7.7; Parkinson's disease: €13.9; personality disorders: €27.3; psychotic disorders: €93.9; sleep disorders: €35.4; somatoform disorder: €21.2; stroke: €64.1; traumatic brain injury: €33.0. It should be noted that the revised estimate of those disorders included in the previous 2004 report constituted €477 billion, by and large confirming our previous study results after considering the inflation and population increase since 2004. Further, our results were consistent with administrative data on the health care expenditure in Europe, and comparable to previous studies on the cost of specific disorders in Europe. Our estimates were lower than comparable estimates from the US.

Discussion

This study was based on the best currently available data in Europe and our model enabled extrapolation to countries where no data could be found. Still, the scarcity of data is an important source of uncertainty in our estimates and may imply over- or underestimations in some disorders and countries. Even though this review included many disorders, diagnoses, age groups and cost items that were omitted in 2004, there are still remaining disorders that could not be included due to limitations in the available data. We therefore consider our estimate of the total cost of the disorders of the brain in Europe to be conservative. In terms of the health economic burden outlined in this report, disorders of the brain likely constitute the number one economic challenge for European health care, now and in the future. Data presented in this report should be considered by all stakeholder groups, including policy makers, industry and patient advocacy groups, to reconsider the current science, research and public health agenda and define a coordinated plan of action of various levels to address the associated challenges.

Recommendations

Political action is required in light of the present high cost of disorders of the brain. Funding of brain research must be increased; care for patients with brain disorders as well as teaching at medical schools and other health related educations must be quantitatively and qualitatively improved, including psychological treatments. The current move of the pharmaceutical industry away from brain related indications must be halted and reversed. Continued research into the cost of the many disorders not included in the present study is warranted. It is essential that not only the EU but also the national governments forcefully support these initiatives.  相似文献   
948.

Background and purpose

Surveillance studies evaluating antimicrobial susceptibilities are of great value in preventing the spread of resistant pathogens by elucidating the trend of resistance in commonly used antibiotics and as a consequence providing information for prescribing the most appropriate agent. This study is a longitudinal antimicrobial resistance surveillance study designed to evaluate the trend in antimicrobial resistance to gram negative microorganisms from 2007 to 2010.

Method

During a four-year period (2007–2010) isolates derived from all patients admitted to infectious diseases ward of Imam Khomeini Hospital, the major referral center for infectious disease in Iran with the highest admission rates, were evaluated. Based on disk diffusion method and zone of inhibition size, the microorganism was regarded as to be sensitive, resistant or has intermediate susceptibility to the antimicrobial agents.

Results

The widest spread Gram-negative microorganism in all of isolates taken together in our study was E.coli (30%) followed by Stenotrophomonas maltophilia in 28.6% and Enterobacter spp. in 11.9%, respectively. The susceptibility to amikacin, imipenem, piperacillin/tazobactam, and nitrofurantoin was equal or above 50% for all microorganisms over four years. However, the susceptibility to ampicillin, ampicillin/sulbactam, cefotaxim, and ceftriaxone was less than 50% in derived isolates during the study period.

Conclusion

In conclusion, the finding of the present study revealed that resistance rate to common antimicrobial agents in Iran is growing and isolates were susceptible mostly to broad-spectrum antibiotics including imipenem and piperacillin/tazobactam.  相似文献   
949.
950.

Purpose  

To investigate the in vitro release of octreotide acetate, a somatostatin agonist, from microspheres based on a hydrophilic polyester, poly(D,L-lactide-co-hydroxymethyl glycolide) (PLHMGA).  相似文献   
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