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81.
In this paper we analyze a fibrosis scoring method based on measurement of the fibrillar collagen area from second harmonic generation (SHG) microscopy images of unstained histological slices from human liver biopsies. The study is conducted on a cohort of one hundred chronic hepatitis C patients with intermediate to strong Metavir and Ishak stages of liver fibrosis. We highlight a key parameter of our scoring method to discriminate between high and low fibrosis stages. Moreover, according to the intensity histograms of the SHG images and simple mathematical arguments, we show that our area-based method is equivalent to an intensity-based method, despite saturation of the images. Finally we propose an improvement of our scoring method using very simple image processing tools.OCIS codes: (180.4315) Nonlinear microscopy, (170.1610) Clinical applications, (170.3880) Medical and biological imaging, (170.4580) Optical diagnostics for medicine, (110.2960) Image analysis  相似文献   
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The Diabetic Retinopathy Clinical Research Network (DRCR.net) performs studies on new treatments for diabetic retinopathy. This review aims to summarise recent findings from DRCR.net studies on the treatment of diabetic macular oedema. We performed a PubMed search of articles from the DRCR.net, which included all studies pertaining to the treatment of diabetic maculopathy. The main outcome measures were retinal thickening as assessed by central subfield thickness on optical coherence tomography and improvement of visual acuity on the Early Treatment Diabetic Retinopathy Study (ETDRS) chart. Findings from each study were divided into modalities of treatment, namely photocoagulation, bevacizumab, triamcinolone, ranibizumab and vitrectomy. While modified ETDRS focal/grid laser remains the standard of care, intravitreal corticosteroids or anti-vascular endothelial growth factor agents have also proven to be effective, although they come with associated side effects. The choice of treatment modality for diabetic macular oedema is a clinical judgement call, and depends on the patient’s clinical history and assessment.  相似文献   
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Patients with severe aplastic anemia (SAA) and a neutrophil (PMN) count of less than 0.5 x 10(9)/L are exposed to a high risk of early mortality when treated with antilymphocyte globulin (ALG) and steroids, with the major problem being infectious complications. The addition of human recombinant granulocyte colony-stimulating factor (rhG-CSF) to ALG may reduce early mortality by improving neutrophil counts in the short term. To test the feasibility of this approach, the SAA Working Party of the European Group for Blood and Marrow Transplantation (EBMT) designed a pilot study that included rhG-CSF (5 micrograms/kg/d, days 1 through 90), horse ALG (HALG; 15 mg/kg/d, days 1 through 5), methylprednisolone (2 mg/kg/d, days 1 through 5, then tapering the dose), and cyclosporin A (CyA; 5 mg/kg/d orally, days 1 through 180). Patients with newly diagnosed acquired SAA (untreated) and with neutrophil counts of < or = 0.5 x 10(9)/L were eligible. Forty consecutive patients entered this study and are evaluable with a minimum follow up of 120 days: the median age was 16 years (range, 2 to 72 years), the interval from diagnosis to treatment was 24 days, and the median PMN count was 0.19 x 10(9)/L. Twenty-one patients had hemorrhages, and 19 were infected at the time of treatment. Overall, treatment was well tolerated: the median maximum PMN count during rhG- CSF administration was 12 x 10(9)/L (range, 0.4 x 10(9)/L to 44 x 10(9)/L). There were three early deaths (8%) due to infection. Four patients (10%) showed no recovery, whereas 33 patients (82%) had trilineage hematologic reconstitution and became transfusion- independent at a median interval of 115 days from treatment. Median follow up for surviving patients is 428 days (range, 122 to 1,005). Actuarial survival is 92%: 86% and 100% for patients with PMN counts less than 0.2 x 10(9)/L or between 0.2 x 10(9)/L and 0.5 x 10(9)/L, respectively. This study suggests that the addition of rhG-CSF to ALG and CyA is well tolerated, is associated with a low risk of mortality, and offers a good chance of hematologic response. This protocol would appear to be an interesting alternative treatment for SAA patients with a low PMN count who lack an HLA-identical sibling.  相似文献   
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Pituitary - The aim of the present study is to assess the predictive value of the suprasellar volume (SSV) of nonfunctioning pituitary adenomas (NFPAs) for visual field (VF) impairment in order to...  相似文献   
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With the development and increasing accessibility of new genomic tools such as next-generation sequencing, genome-wide association studies, and genomic stratification models, the debate on genetic discrimination in the context of life insurance became even more complex, requiring a review of current practices and the exploration of new scenarios. In this perspective, a multidisciplinary group of international experts representing different interests revisited the genetics and life insurance debate during a 2-day symposium ‘Life insurance: breast cancer research and genetic risk prediction seminar'' held in Quebec City, Canada on 24 and 25 September 2012. Having reviewed the current legal, social, and ethical issues on the use of genomic information in the context of life insurance, the Expert Group identified four main questions: (1) Have recent developments in genomics and related sciences changed the contours of the genetics and life insurance debate? (2) Are genomic results obtained in a research context relevant for life insurance underwriting? (3) Should predictive risk assessment and risk stratification models based on genomic data also be used for life insurance underwriting? (4) What positive actions could stakeholders in the debate take to alleviate concerns over the use of genomic information by life insurance underwriters? This paper presents a summary of the discussions and the specific action items recommended by the Expert Group.Access to genetic information by life insurers has been a topic of discussion for many years.1 The possibility of using genetic data to underwrite an applicant''s insurance policy has given rise to concerns about the emergence of ‘genetic discrimination''. Genetic discrimination in the field of life insurance is not necessarily illegal in that in insurance underwriting questions about health, family history of disease, or genetic information may constitute legal exceptions to antidiscrimination legislation.2, 3 Nevertheless, the expression ‘genetic discrimination'' has acquired public notoriety4 and we will use more neutral language in this paper.Countries including Canada, the United States, Russia, and Japan5 have chosen not to adopt laws specifically prohibiting access to genetic data for underwriting by life insurers.6 In these countries, life insurance underwriters treat genetic data like other types of medical or lifestyle data. However, a growing number of countries such as Belgium, France, and Norway5 have chosen to adopt laws to prevent or limit insurers'' access to genetic data for life insurance underwriting. Other countries including Finland and the United Kingdom have developed voluntary arrangements with the industry (ie moratoria) with similar objectives.7Life insurance is a private contract between the policy-holder and the insurer. Its principal role is to provide financial security to the beneficiaries in the event of the insured''s death.8 Because of this important role, life insurance is often required, or strongly recommended for those seeking loans to acquire primary social goods, like housing or cars.9 In Europe, a consequence of the advent of the welfare state is that private insurance has increasingly played a complementary and supplementary role to social insurance by offering additional security and protection to the population. Thus, in this region, insurance is often considered as a social good that allows individuals to live a comfortable life and as a tool to promote social integration.10 In other regions of the world, this social role of life insurance is also recognized to a lesser extent. Given this social role, equitable access to life insurance is perceived as a sensitive issue and cases of denial looked upon negatively in popular media. Although documented incidents of denial or of increased premiums on the basis of genetic information have remained limited to the context of a few relatively well known, highly penetrant, familial, adult-onset, genetic conditions,11 they have nevertheless generated significant public concern. Fear that insurers will have access to genetic information generated in a clinical or research setting for use in underwriting has been reported by several studies as a reason for non-participation in genetic research or recommended clinical genetic testing.12, 13, 14The clinical utility of genetic testing for monogenic disorders such as Huntington disease, and hereditary forms of cancer are well established.15 However, genomic risk profiles based on the known common susceptibility variants have limited utility in risk prediction at the individual level, although they could be used for risk stratification in prevention programmes in populations.16 Today, a new era of genomic research has made it increasingly affordable to scan the entire genome of an individual. Researchers and physicians can interpret these data together with medical and lifestyle information in the form of sophisticated risk prediction models.17 Moreover, improvement in computing technologies coupled with the Internet make predictive information increasingly available, whether through direct-to-consumer marketing of genetic tests, genetic data sharing online communities, or international research database projects. Given these important technological and scientific changes, and their impact on various stakeholders. The term ‘stakeholders'' is used in this text to refer to the following groups of individuals: actuaries (person who computes insurance risk and premium rates based on statistical data), academic researchers, community representatives, ethics committees, genetic counsellors, genomic researchers, human rights experts, insurers, governmental representatives, non-governmental organisations, patient representatives, physicians, policy makers, popular media, reinsurers (company in charge of calculating the risk and premium amount for insuring a particular customer), research participants, and underwriters (company or person in charge of calculating the risk involved in providing insurance for a particular customer and to decide how much should be paid for the premium). This list is not meant to be exhaustive as relevant new groups may emerge as this topic further develops in the coming years. A multidisciplinary group of international experts representing different interests (hereinafter ‘the Expert Group'') revisited the genetics and life insurance debate. The following text presents a summary of the issues discussed and the ‘Action Items'' agreed upon by the Expert Group at the ‘Life Insurance, Risk Stratification, and Personalized Medicine Symposium''.  相似文献   
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There is little evidence on the impact of malaria control on the health system, particularly at the facility level. Using retrospective, longitudinal facility-level and patient record data from two hospitals in Zambia, we report a pre-post comparison of hospital admissions and outpatient visits for malaria and estimated costs incurred for malaria admissions before and after malaria control scale-up. The results show a substantial reduction in inpatient admissions and outpatient visits for malaria at both hospitals after the scale-up, and malaria cases accounted for a smaller proportion of total hospital visits over time. Hospital spending on malaria admissions also decreased. In one hospital, malaria accounted for 11% of total hospital spending before large-scale malaria control compared with < 1% after malaria control. The findings demonstrate that facility-level resources are freed up as malaria is controlled, potentially making these resources available for other diseases and conditions.  相似文献   
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