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11.
BackgroundMalnourishment is commonly seen in ageing, cancer and many chronic conditions, and is associated with poorer prognosis.AimWe set out to collect all currently available evidence on the association between nutritional status assessed with a validated screening tool and prognosis or course of treatment in older patients with cancer, and on the benefit of nutritional interventions in improving these outcomes.MethodsA systematic search in MEDLINE and EMBASE.ResultsWe included 71 studies on the association between nutritional status and outcome in (older) patients with cancer and 17 studies on the benefit of nutritional interventions in improving outcomes in this patient population. There is a significant association between nutritional status and increased intermediate- and long-term mortality (hazard ratio 1.87 (95% confidence interval 1.62–2.17). Those with poorer nutritional status were less likely to complete oncologic treatment according to plan and had higher health care consumption. Benefit of dietary interventions was limited although dietary counselling may lead to improved quality of life while nutritional support may lead to a decrease in post-operative complication rates.ConclusionNutritional status is associated with poorer survival, decreased treatment completion and higher health care consumption and nutritional interventions are only able to negate these negatives outcome to a very limited degree.  相似文献   
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OBJECTIVES: To determine the relative extent to which the National Institute for Health and Clinical Excellence (NICE) appraises new versus existing technologies, and pharmaceutical versus nonpharmaceutical health technologies. METHODS: We categorized technologies within NICE appraisals published between March 2000 and June 2006 by type and classified them as new or existing using the timeline between launch in the United Kingdom and referral to NICE. We used a 3-year postlaunch cutoff to determine whether a technology was new, with a sensitivity analysis of 1 and 5 years. RESULTS: We reviewed 159 technologies from 88 appraisals. Of these, 84 (53 percent) were new (sensitivity analysis 36 to 67 percent) and 75 (47 percent) were existing technologies. A total of 119 (75 percent) were pharmaceuticals, 22 (14 percent) were devices, 14 (9 percent) were procedures, and 4 (3 percent) were categorized as miscellaneous. Classification according to newness and technology type showed that 62 percent (42 to 75 percent) of the pharmaceuticals appraised were new. CONCLUSIONS: By developing and applying a definition of new, we have found that the criticism of the bias toward new technologies is unfounded when applied to the appraisal program overall. At the same time, new pharmaceuticals are over-represented in the program compared with devices and procedures. This domination may cause inflationary pressures on the health service, but any wholesale move away from the technological frontier may be more costly.  相似文献   
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Background

The debate regarding dichlorodiphenyltrichloroethane (DDT) in malaria prevention and human health is polarized and can be classified into three positions: anti-DDT, centrist-DDT, pro-DDT.

Objective

We attempted to arrive at a synthesis by matching a series of questions on the use of DDT for indoor residual spraying (IRS) with literature and insights, and to identify options and opportunities.

Discussion

Overall, community health is significantly improved through all available malaria control measures, which include IRS with DDT. Is DDT “good”? Yes, because it has saved many lives. Is DDT safe as used in IRS? Recent publications have increasingly raised concerns about the health implications of DDT. Therefore, an unqualified statement that DDT used in IRS is safe is untenable. Are inhabitants and applicators exposed? Yes, and to high levels. Should DDT be used? The fact that DDT is “good” because it saves lives, and “not safe” because it has health and environmental consequences, raises ethical issues. The evidence of adverse human health effects due to DDT is mounting. However, under certain circumstances, malaria control using DDT cannot yet be halted. Therefore, the continued use of DDT poses a paradox recognized by a centrist-DDT position. At the very least, it is now time to invoke precaution. Precautionary actions could include use and exposure reduction.

Conclusions

There are situations where DDT will provide the best achievable health benefit, but maintaining that DDT is safe ignores the cumulative indications of many studies. In such situations, addressing the paradox from a centrist-DDT position and invoking precaution will help design choices for healthier lives.  相似文献   
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Melatonin has multiple receptor-dependent and receptor-independent functions. At the cell membrane, melatonin interacts with its receptors MT1 and MT2, which are expressed in numerous tissues. Genome-wide association studies have recently shown that the MTNR1B/MT2 receptor may be involved in the pathogenesis of type 2 diabetes mellitus. In line with these findings, expression of melatonin receptors has been shown in mouse, rat, and human pancreatic islets. MT1 and MT2 are G-protein-coupled receptors and are proposed to exert inhibitory effects on insulin secretion. Here, we show by immunocytochemistry that these membrane melatonin receptors have distinct locations in the mouse islet. MT1 is expressed in α-cells while MT2 is located to the β-cells. These findings help to unravel the complex machinery underlying melatonin's role in the regulation of islet function.  相似文献   
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Background

In vitro studies have shown the feasibility of coronary lesion grading with computed tomography angiography (CTA), intravascular ultrasound (IVUS) and optical coherence tomography (OCT) as compared to histology, whereas OCT had the highest discriminatory capacity.

Objective

We investigated the ability of CTA and IVUS to differentiate between early and advanced coronary lesions in vivo, OCT serving as standard of reference.

Methods

Multimodality imaging was prospectively performed in 30 NSTEMI patients. Plaque characteristics were assessed in 1083 cross-sections of 30 culprit lesions, co-registered among modalities. Absence of plaque, fibrous and fibrocalcific plaque on OCT were defined as early plaque, whereas lipid rich-plaque on OCT was defined as advanced plaque. Odds ratios adjusted for clustering were calculated to assess associations between plaque types on CTA and IVUS with early or advanced plaque.

Results

Normal findings on CTA as well as on IVUS were associated with early plaque. Non-calcified, calcified plaques and the napkin ring sign on CTA were associated with advanced plaque. On IVUS, fatty and calcified plaques were associated with advanced plaque.

Conclusions

In vivo coronary plaque characteristics on CTA and IVUS are associated with plaque characteristics on OCT. Of note, normal findings on CTA and IVUS relate to early lesions on OCT. Nevertheless, multiple plaque features on CTA and IVUS are related to advanced plaques on OCT, which may make it difficult to use qualitative plaque assessment in clinical practice.  相似文献   
18.
Purpose:To describe the anatomy of the swine urinary system using computed tomography and to discuss the role of this animal as an experimental model for urological procedures.Methods:Three male Landrace pigs underwent computed tomography and the anatomy of the urinary system and renal circulation was analyzed and described.Results:In all animals, 2 kidneys, 2 ureters and one bladder were identified. Each kidney presented a single renal artery vascularization, with a mean diameter on the right of 4.45 and 5.31 mm on the left (p < 0.0001) and single renal vein drainage, with a mean diameter on the right of 5.78 and 5.82 mm on the left (p = 0.0336). The average renal length was 9.85 cm on the right and 10.30 cm on the left (p < 0.0001). The average renal volume was 113.70 cm3 on the right and 109.70 cm3 on the left (p < 0.0001). The average length of the ureter was 19.78 cm on the right and 22.08 cm on the left (p < 0.0001). The average bladder volume was 423.70 cm3.Conclusions:The data obtained show similarities with human anatomy, suggesting the viability of the swine model for planning preclinical trials, basic research, refinement in experimental surgery and surgical training for urological procedures.Key words: Urologic Surgical Procedures, Tomography, X-Ray Computed, Anatomy, Swine  相似文献   
19.
Excimer laser photorefractive keratectomy (PRK) is an experimental treatment to correct myopia (short-sightedness) that is diffusing into use without convincing evidence of safety and efficacy. It has been claimed that PRK may render conventional methods of correcting myopia, such as wearing glasses or contact lenses, obsolete. Since about 25% of the world's population is myopic, the consequences of this technology in terms of benefits, risks, and costs could be truly enormous. The fee for the procedure in various countries such as the United States, the Netherlands, and Australia varies from about US $1500 to US $2250 per eye. In the United States, the Food and Drug Administration, acting as authorized in the Medical Devices Act of 1976, has limited the use of PRK to patients participating in clinical trials. In the Netherlands, in contrast, where medical equipment is not regulated, the method has diffused without controls, although it is not reimbursed by health insurance agencies. The procedure has become controversial in the Netherlands because it is provided privately and has been aggressively and inappropriately promoted. The case illustrates the limitations of health policy concerning technologies provided privately and raises a number of social and political questions.  相似文献   
20.
In clonal beta-cell lines and islets from different species, a variety of calcium channels are coupled to glucose-stimulated insulin secretion. The aim of this study was to identify the voltage-gated calcium channels that control insulin secretion in insulinoma (INS)-1 832/13 cells. The mRNA level of Ca(V)1.2 exceeded that of Ca(V)1.3 and Ca(V)2.3 two-fold. Insulin secretion, which rose tenfold in response to 16.7 mM glucose, was completely abolished by 5 microM isradipine that blocks Ca(V)1.2 and Ca(V)1.3. Similarly, the increase in intracellular calcium in response to 15 mM glucose was decreased in the presence of 5 microM isradipine, and the frequency of calcium spikes was decreased to the level seen at 2.8 mM glucose. By contrast, inhibition of Ca(V)2.3 with 100 nM SNX-482 did not significantly affect insulin secretion or intracellular calcium. Using RNA interference, Ca(V)1.2 mRNA and protein levels were knocked down by approximately 65% and approximately 34% respectively, which reduced insulin secretion in response to 16.7 mM glucose by 50%. Similar reductions in calcium currents and cell capacitance were seen in standard whole-cell patch-clamp experiments. The remaining secretion of insulin could be reduced to the basal level by 5 microM isradipine. Calcium influx underlying this residual insulin secretion could result from persisting Ca(V)1.2 expression in transfected cells since knock-down of Ca(V)1.3 did not affect glucose-stimulated insulin secretion. In summary, our results suggest that Ca(V)1.2 is critical for insulin secretion in INS-1 832/13 cells.  相似文献   
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