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81.
82.
Dentigerous cysts are odontogenic cysts associated with the crowns of unerupted permanent teeth. This article reports the case of a 10-year-old child who presented permanence of deciduous teeth 51, 52, and 53. Panoramic radiograph showed extensive cystic lesion involving the teeth 11, 12 and 13, which were included. Diagnosis of dentigerous cysts was confirmed by incisional biopsy and the treatment was chosen in order to preserve the associated permanent teeth. At 2 years of follow-up, the impacted teeth are positioning itself spontaneously toward its eruption and the patient was referred for orthodontic assessment.  相似文献   
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84.
House dust mite (HDM) feces and molds are the main allergens involved in allergic asthma. Differences exist between the housing fungal biome of allergic patients and standard or unhealthy housing. House dust mite (HDM) feed off spores and transport them on their bodies, but do they have fungal food preferences? We observed Dermatophagoïdes farinae in vitro with 16 mold menus and repeated the experiment 10 times. This observation led us to define Alternaria alternata, Cladosporium sphaerospermum, and Wallemia sebi as “tasty” molds and Penicillium chrysogenum, Aspergillus versicolor, and Stachybotrys chartarum as “repulsive” molds. The food preferences of D. farinae may play a role in the following two phenomena: a decrease in spore numbers due to HDM consumption and a scattering of spores that stick to the bodies of HDMs. The extent of these two phenomena should be estimated in future studies for other common domestic HDM species.  相似文献   
85.
Foraging range, an important component of bee ecology, is of considerable interest for insect-pollinated plants because it determines the potential for outcrossing among individuals. However, long-distance pollen flow is difficult to assess, especially when the plant also relies on self-pollination. Pollen movement can be estimated indirectly through population genetic data, but complementary data on pollinator flight distances is necessary to validate such estimates. By using radio-tracking of cowpea pollinator return flights, we found that carpenter bees visiting cowpea flowers can forage up to 6 km from their nest. Foraging distances were found to be shorter than the maximum flight range, especially under adverse weather conditions or poor reward levels. From complete flight records in which bees visited wild and domesticated populations, we conclude that bees can mediate gene flow and, in some instances, allow transgene (genetically engineered material) escape over several kilometers. However, most between-flower flights occur within plant patches, while very few occur between plant patches.  相似文献   
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Background

Exercise-based cardiac rehabilitation is considered an important adjunct treatment and secondary prevention measure in patients with coronary artery disease (CAD). However, the issues of training modality and exercise intensity for CAD patients remain controversial.

Objective

Main aim of the present study is to test the hypothesis that aerobic interval training (AIT) yields a larger gain in peak aerobic capacity (peakVO2) compared to a similar training programme of moderate continuous training (MCT) in CAD patients.

Study design

In this multicentre study stable CAD patients with left ventricular ejection fraction > 40% will be randomized after recent myocardial infarction or revascularization (PCI or CABG) to a supervised 12-week programme of three weekly sessions of either AIT (85–90% of peak oxygen uptake [peakVO2], 90–95% of peak heart rate) or MCT (60–70% of peakVO2, 65–75% of peak heart rate). The primary endpoint of the study is the change of peakVO2 after 12 weeks training. Secondary endpoints include safety, changes in peripheral endothelial vascular function, the evolution of traditional cardiovascular risk factors, quality of life and the number and function of circulating endothelial progenitor cells as well as endothelial microparticles.Possible differences in terms of long-term adherence to prescribed exercise regimens will be assessed by regular physical activity questionnaires, accelerometry and reassessment of peakVO2 12 months after randomization. A total number of 200 patients will be randomized in a 1:1 manner (significance level of 0.05 and statistical power of 0.90). Enrolment started December 2010; last enrolment is expected for February 2013.  相似文献   
88.

Background:

Although prior studies have suggested an inverse association between liver transplant centre volume and postoperative patient mortality, more recent analyses have failed to confirm this association. To date, all studies of the relationship between centre volume and outcomes in liver transplantation have been cross-sectional in design.

Objective:

The objective of our study was to examine temporal trends in the volume–outcomes relationship for liver transplantation.

Methods:

We used information obtained from the Scientific Registry of Transplant Recipients (SRTR) programme-specific data reports to examine the outcomes of adult liver transplant recipients stratified by annual centre volume. This relationship between centre volume and patient outcomes was assessed over three consecutive time periods from 2000 through 2007.

Results:

The overall 25% increase in adult liver transplant volume in the USA from 2000 to 2007 appeared to be distributed fairly equally among existing transplant centres. In the earliest time period of our analysis, high-volume centres achieved superior risk-adjusted 1-year patient outcomes compared with low-volume centres. By the third and most recent time period of the analysis, this discrepancy between the outcomes of high- and low-volume centres was no longer statistically apparent.

Conclusions:

The relationship between centre volume and patient outcomes for liver transplantation in the USA has become less pronounced over time, suggesting that the use of procedure volume as a marker of liver transplant centre quality cannot be justified. The performance-based review process currently utilized in the USA may have contributed to this diminishing influence of centre volume on liver transplant recipient outcomes. This type of review process should be considered as a potential alternative to the volume-based referral initiatives that have been developed for other non-transplant, complex surgical procedures.  相似文献   
89.
Our study was performed to sequentially analyze the expression of the intestinal mucin MUC2 and of the gastric mucin MUC5AC as indicators during progression of preneoplastic biomarkers in rat colon. F344 rats were sacrificed 2, 4, 8, 12, 24 and 36 weeks after injection of 1,2-dimethylhydrazine (DMH, 200 mg/kg, i.p.). The expression of MUC2 and of MUC5AC was studied by immunohistochemistry in preneoplastic lesions classified in two categories: histologically altered foci (HAF) and beta-catenin accumulated crypts (BCAC). HAF appeared 4 weeks after DMH injection. Their crypt multiplicity stagnated with time (3-4 crypts/foci) but gastric MUC5AC mucin was always observed in some goblet cells of the lesions of this category. In contrast, MUC2-immunostaining was not modified compared to the adjacent crypts. Double-immunofluorescence revealed that goblet cells which produced MUC5AC continued to express MUC2. In BCAC, crypt multiplicity and mucin expression strongly evolved with time. These lesions were observed only 8 weeks after DMH-injection. At this stage, 20% of BCAC showed a decreased MUC2 expression and 33% were MUC5AC immunopositive. At the 36-week point, 43% of BCAC had a reduced MUC2 staining and 90% were positive for MUC5AC. This immunopositivity was often observed in all the cells of these lesions. Seldom, some BCAC were depleted at the same time in MUC2 and in MUC5AC. Similar alterations in mucin expression were observed in human colonic pre-neoplastic lesions. These findings suggest that a decrease in MUC2 expression and staining of MUC5AC in non-goblet-like cells predicts histological progression of preneoplastic lesions.  相似文献   
90.
Autosomal‐recessive retinitis pigmentosa (arRP) was recently associated with mutations in a novel gene EYS, spanning over 2 Mb, making it the largest known gene expressed in the human eye. The purpose of this study was to establish the prevalence and nature of EYS mutations in a clinically well‐characterized cohort of 239 sporadic and arRP French cases. Direct sequencing of EYS was performed in 186 subjects for whom known mutations had previously been excluded by applying microarray technology. We mostly identified novel mutations in EYS in a total of 29 patients: Fifteen of the mutations were predicted to create premature stop codons and two represent exonic deletions. In addition, twenty missense, silent or splice‐site mutations were detected. Patients revealed homozygous or compound heterozygous mutations and in some cases, only a single mutation. Most patients showed classical signs of RP with relatively preserved central vision and visual field until late in the course of the disorder. One patient showed predominance of the disease in the inferior part of the retina suggesting potential phenotypic variability. With a prevalence of 12% or more we provide evidence that EYS is a major gene for RP in France and probably elsewhere. © 2010 Wiley‐Liss, Inc.  相似文献   
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