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111.
The technical consultation in Montreux, organised by World Health Organization and UNAIDS in 2007, recommended male circumcision as a method for preventing HIV transmission. This consultation came out of a long process of releasing reports and holding international and regional conferences, a process steered by an informal network. This network's relations with other parties is analysed along with its way of working and the exchanges during the technical consultation that led up to the formal adoption of a recommendation. Conducted in relation to the concepts of a ‘hybrid forum’ and ‘network’, this article shows that the decision was based on the formation and consolidation of a network of persons. They were active in all phases of this process, ranging from studies of the recommendation's efficacy, feasibility and acceptability to its adoption and implementation. In this sense, this consultation cannot be described as the constitution of a ‘hybrid forum’, which is characterised by its openness to a debate as well as a plurality of issues formulated by the actors and of resources used by them. On the contrary, little room was allowed for contradictory discussions, as if the decision had already been made before the Montreux consultation.  相似文献   
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Ce3+-doped Y3Al5O12 (YAG:Ce) nanocrystals were synthesized by a unique solvothermal method, under sub-critical conditions. A home-made autoclave was used, operating in a larger pressure and temperature range than that with conventional commercial equipment and allowing direct in situ photoluminescence (PL) and X-ray absorption characterizations. The study of various synthesis conditions (pressure, temperature, precursor concentration, reaction time) allowed the best reaction conditions to be pinpointed to control YAG:Ce nanocrystal size, as well as crystal quality, and to get efficient optical properties. Without any post thermal treatment, we succeeded in obtaining well-crystallized YAG:Ce nanocrystals (30–200 nm), displaying typical PL properties of YAG:Ce with a maximal emission at 550 nm. The pristine 100 nm-sized YAG:Ce nanoparticles present an internal quantum yield of about 40 ± 5%. In situ X-ray absorption near edge spectroscopy demonstrates the presence of Ce4+ in nanocrystals elaborated at high temperature, resulting from the oxidation of Ce3+ during the crystallization process.

This modified solvothermal method, combined with in situ photoluminescence measurements, allows the synthesis of well-crystallized size-controlled YAG:Ce nanocrystals.  相似文献   
114.
Clinical Rheumatology - Articular cartilage and periarticular muscle tissues are strongly affected during knee osteoarthritis (OA). Creatine kinase (CK) is an enzyme expressed in several tissues,...  相似文献   
115.
Gastric lesions secondary to long-distance running   总被引:3,自引:0,他引:3  
Gastrointestinal disorders have been reported during long- distance running. The purpose of this study was to evaluate the effects of prolonged exercise on the upper digestive tract. Seven subjects were submitted to a standard endoscopic examination of the upper digestive tract before and after long- distance running (range 18– 50 km). Mucosal biopsy specimens were taken during all endoscopies. After running, all runners had histologically pathological features in the stomach. Vascular lesions were present in the chorion in six subjects after running, with the intensity of the lesions ranging from congestion to hemorrhage. Postexercise histological examination also showed a decrease in mucosal secretion. These lesions secondary to prolonged exercise indicate the presence of hemodynamic perturbations in the upper digestive tract.  相似文献   
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The adhesion of haematopoietic progenitor cells (HPC) to the bone marrow microenvironment is a process regulated by cytokines. In this study, we have shown that flt3-ligand (FL), a growth factor that controls early haematopoiesis, regulated the function and expression of the beta-1 integrins, very late antigen (VLA)-4 and VLA-5 on HPC. The modulation of the adhesiveness of HPC by FL was studied by adhesion assays on umbilical vein endothelial cells (HUVEC). Stimulation by FL induced two peaks of increased adhesiveness of HPC. The first peak was at around 30 min and was mechanistically related to an activation of the beta-1 integrins, mainly VLA-4 and VLA-5. The second peak was at around 12 h and was related to increased expression of VLA-4 and VLA-5. The control of HPC adhesiveness by FL is a previously unreported property of FL that may be important for the homing and the retention of flt3-expressing HPC within the bone marrow microenvironment.  相似文献   
118.

Background

Depressive and anxiety disorders (DAD) have become a major public health problem. Multiple trauma is known to increase the risk of DAD through a sensitization mechanism. We investigate the hypothesis that resilience is a mediator of this mechanism.

Methods

Former Hidden Children (FHC), the Jewish youths who spent World War II in various hideaway shelters across Nazi-occupied Europe, were compared with a control group. In each group, we measured the presence of multiple traumas, the resilience with the Resilience Scale for Adults, which has a six factors solution, and the DAD with the Hopkins Symptoms Checklist. We test a mediated moderation model with childhood trauma as the predictor; Later trauma as the moderator; Resilience as the mediator; and DAD as the outcome variable.

Results

Results are consistent with a sensitization model of DAD mediated by resilience: confrontation with a primary trauma during childhood followed by secondary trauma(s) after childhood damages resilience, which, in turn, results in higher level of DAD.

Limitations

We are unable to differentiate if the sensitization process is a consequence of the nature of the trauma endured by FHC (long-standing exposure to extreme external events) or a consequence of the fact that this first trauma occurred during childhood.

Conclusions

Resilience construct is multi-factorial and a limited damaging of some of the factors is sufficient to lead to DAD even if other factors remain unaltered. Resilience can be altered by multiple traumas and, therefore, needs to be bolstered in therapy sessions.  相似文献   
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European Journal of Clinical Microbiology & Infectious Diseases - Molecular diagnosis on nasopharyngeal swabs (NPS) is the current standard for COVID-19 diagnosis, but saliva may be an...  相似文献   
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