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991.
Hemangioblasts are capable of differentiation into vascular structures and blood. Patients with von Hippel–Lindau (VHL) disease develop hemangioblastomas which are composed of VHL-deficient tumor cells with protracted hemangioblastic differentiation potential. In a subset of these tumors, hemangioblastic differentiation is characterized by different stages of red blood cell formation. It has remained controversial, however, whether VHL-deficient hemangioblastic cells are similarly capable of differentiating into vascular cells and functioning vascular structures in vivo.  相似文献   
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Inherited cardiac conditions (ICCs) can lead to sudden cardiac death at any age, yet are often asymptomatic and clinically undetected. Prophylactic interventions are available and cascade testing is recommended to identify family members at risk. When a disease-causing mutation has been identified in a family, pre-symptomatic genetic testing (PSGT) is available. This study explores perceptions of the cascade process, impact of PSGT and attitudes towards direct contact as an alternative to family-mediated dissemination for ICCs. In depth, interviews were conducted with 22 participants eligible for PSGT for Hypertrophic Cardiomyopathy or Long QT syndrome. Data were analysed using an inductive, thematic approach. Risk is perceived to be low pre-test in the absence of symptoms, and participants frequently test with the aim of ruling out risk to self and children. Testing of children is a complex decision; although older participants have concerns about possible adverse effects of genetic testing early in the life course, young participants are pragmatic about their result. The meaning of a positive genetic test result may be difficult to conceptualise in the absence of clinical evidence of disease, and this may deter further dissemination to at-risk family members. A majority of participants see advantages in direct contact from health professionals and support it in principle. Implications for practice include addressing risk perception pre-test, and presenting genetic test information as part of a risk stratification process rather than a binary outcome. Families may require more support or intervention in cascading genetic test information.  相似文献   
995.
A convenient one-pot method for the preparation of N2,6-diaryl-5,6-dihydro-1,3,5-triazine-2,4-diamines was developed using a three-component synthesis of 1,6-diaryl-1,6-dihydro-1,3,5-triazine-2,4-diamines followed by their Dimroth rearrangement to the desired products. The prepared compounds crystallized from ethanol as ethanol clathrates (1 : 1). X-ray crystallography on several products confirmed the adoption of 5,6-dihydro-tautomer. The thermal analysis and powder X-ray diffraction experiments on selected compounds suggested that thermal desolvation of crystals was irreversible.

One-pot synthesis and analysis of stable dihydrotriazine-EtOH clathrates.  相似文献   
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Epstein–Barr virus (EBV) and Kaposi's sarcoma‐associated herpesvirus (KSHV) are two γ‐herpesviruses identified in humans and are strongly associated with the development of malignancies. Murine γ‐herpesvirus (MHV‐68) is a naturally occurring rodent pathogen, representing a unique experimental model for dissecting γ‐herpesvirus infection and the immune response. These γ‐herpesviruses actively antagonize the innate and adaptive antiviral responses, thereby efficiently establishing latent or persistent infections and even promoting development of malignancies. In this review, we summarize immune evasion strategies of γ‐herpesviruses. These include suppression of MHC‐I‐restricted and MHC‐II‐restricted antigen presentation, impairment of dendritic cell functions, downregulation of costimulatory molecules, activation of virus‐specific regulatory T cells, and induction of inhibitory cytokines. There is a focus on how both γ‐herpesvirus‐derived and host‐derived immunomodulators interfere with adaptive antiviral immunity. Understanding immune‐evasive mechanisms is essential for developing future immunotherapies against EBV‐driven and KSHV‐driven tumors. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   
998.
Background:Accurate calculation and adjustment of insulin doses is integral to maintaining glycemic control in insulin treated patients. Difficulties with insulin dose calculations may lead to poor adherence to blood glucose monitoring and insulin treatment regimes, resulting in poor metabolic control. The main objective of this study was to evaluate ease of use and user preference of a high specification touch screen blood glucose meter, which has an in-built insulin calculator, compared to patients’ usual method of testing blood glucose and deciding insulin doses.Methods:Patients with diabetes on a multiple daily injection insulin regime used the Test Meter without the insulin calculator and 1 of 3 comparator meters, each for a 7-day period. They then used the Test Meter with the in-built calculator for 10 days. Patients completed an ease of use questionnaire after each 7-day period, a preference questionnaire after the second 7-day period, and a questionnaire comparing the Test Meter with their usual method after the final 10-day period.Results:Of 164 patients who completed the study, 76% stated a preference for the Test Meter as a diabetes management tool compared to their usual method. A small number of patients preferred familiar methods and/or calculating insulin doses themselves. The log book function of meters was important to most patients.Conclusions:The Test Meter system with in-built insulin calculator supports people to better manage their diabetes and increases their confidence. Patients have different needs and preferences which should be acknowledged and supported in a patient centered health service.  相似文献   
999.
1000.

Background

Nontuberculous mycobacteria (NTM) infection is an emerging, but neglected public health concern in China.

Findings

To investigate diagnostic delay of NTM diseases in China, we analyzed 91 patients with pulmonary NTM infection in ShandongProvince. The median diagnostic delay time of the analyzed patients was 84 days, which was significantly associated with rural inhabitance (135 days vs. 73 days of urban inhabitance, p?<?0.01) and lower level of first visiting hospitals/clinics (70 and 82 days of tertiary and secondary hospitals/clinics respectively vs. 120 days of primary hospitals/clinics, p?<?0.05). M. farcinogenes was isolated from a 79-year-old male patient, which is the first report of pulmonary infection in humans.

Conclusions

Our results indicate a significant diagnostic delay of NTM diseases in China, especially for rural patients with limited access to higher-level healthcare services.
  相似文献   
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