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991.
992.
BackgroundCystic fibrosis (CF) can be a devastating disease. Disorders in essential fatty acid state are increasingly reported and various supplementation trials have been performed in an attempt to improve outcomes. However, the mechanisms leading to these disturbances remain elusive.We wanted to investigate the role of the diseased CF lung on fatty acid profiles.MethodsWe compared fatty acid profiles in patients with CF after lung transplantation (n = 11) to age-matched healthy controls and homozygous F508del patients (n = 22 each).ResultsCompared to healthy controls, in patients with CF, there are decreased levels of docosahexaenoic, linoleic and arachidonic acid and increased levels of mead acid. In patients that underwent a lung transplantation, levels of docosahexaenoic, linoleic and arachidonic acid were normal. Mead acid did not decrease significantly.ConclusionsThe diseased CFTR deficient lung is a major determinant in the disturbed fatty acid profile in CF.  相似文献   
993.
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995.
BackgroundHigh-velocity low-amplitude thrust manipulations (HVLAM) are routinely used in osteopathic treatment. Despite the large number of studies that have been realized till now, the effects of spinal HVLAM on the physiological properties of muscles and nerves are not fully characterized.ObjectiveThe present study was designed to investigate the effects of a spinal lumbar L4/L5 HVLAM on the functional properties of the soleus T reflex in asymptomatic young adults.DesignControlled pre/post measures experimental design.MethodsRight and left soleus T reflexes were elicited by striking right and left Achilles tendons with an instrumented reflex hammer and the electromyographic (EMG) signals were monitored in right and left soleus muscles. The amplitude and latency of EMG responses were measured before and after the delivery of a HVLAM targeting the L4/L5 segment. The conduction velocity was calculated from the latency value.Subjects50 asymptomatic adults met all inclusion criteria. They were randomly allocated to either group a) receiving a sham manipulation (SM), or b) a HVLAM. Because of subject loss, the final size of SM and HVLAM groups was 24 and 18, respectively.ResultsOur data show that the conduction velocity, but not the amplitude of the T reflex, is significantly increased by HVLAM in both soleus muscles with small to medium effect size. SM neither changes the amplitude nor modifies the conduction velocity.ConclusionOur data show that a lumbar L4/L5 HVLAM modifies the electrophysiological properties of the soleus T reflex.  相似文献   
996.
This article describes the creation of an objective structured teaching examination (OSTE) to assess a dental faculty development program. An OSTE is a performance-based measure that utilizes standardized students and is designed to measure observable teaching skills. In spring 2010, the authors developed, implemented, and evaluated an OSTE to assess a New York University College of Dentistry (NYUCD) faculty development program, Class ACTS (Advanced Clinical Teaching Scholars). They created a three-station OSTE to measure changes in teaching skills resulting from participation in Class ACTS. Dental student teaching assistants were trained to act as standardized students and patients and to use the rating forms. The faculty members' OSTE scores and ratings increased after participating in the Class ACTS program in all fifteen teaching domains tested, and statistically significant improvements occurred in nine of the fifteen domains. A search of the relevant literature suggests that this is the first time that an OSTE has been used to assess a faculty development program in dental education. This study's results appear to support NYUCD's faculty development efforts to improve the teaching skills of its faculty members.  相似文献   
997.
Aim: To assess the effectiveness of mineral trioxide aggregate (MTA) used as an indirect pulp-capping material in human molar and premolar teeth. Methodology: We conducted a clinical evaluation of 60 teeth, which underwent an indirect pulp-capping procedure with either MTA or calcium hydroxide cement (Dycal®). Calcium hydroxide was compared with MTA and the thickness of the newly formed dentine was measured at regular time intervals. The follow-up was at 3 and 6 months, and dentine formation was monitored by radiological measurements on digitised images using Mesurim Pro® software. Results: At 3 months, the clinical success rates of MTA and calcium hydroxide were 93% and 73%, respectively (P = 0.02). At 6 months, the success rate was 89.6% with MTA, and remained steady at 73% with calcium hydroxide (P = 0.63). The mean initial residual dentine thickness was 0.23 mm, and increased by 0.121 mm with MTA and by 0.136 mm with calcium hydroxide at 3 months. At 6 months, there was an increase of 0.235 mm with MTA and of 0.221 mm with calcium hydroxide. Conclusions: A higher success rate was observed in the MTA group relative to the Dycal® group after 3 months, which was statistically significant. After 6 months, no statistically significant difference was found in the dentine thickness between the two groups. Additional histological investigations are needed to support these findings.Key words: Calcium hydroxide, dentine bridge, mineral trioxide aggregate, pulp capping, randomised controlled trial  相似文献   
998.
We examined the electrophysiological correlates of retention in auditory short-term memory (ASTM) for sequences of one, two, or three tones differing in timbre but having the same pitch. We focused on event-related potentials (ERPs) during the retention interval and revealed a sustained fronto-central ERP component (most likely a sustained anterior negativity; SAN) that became more negative as memory load increased. Our results are consistent with recent ERP studies on the retention of pitch and suggest that the SAN reflects brain activity mediating the low-level retention of basic acoustic features in ASTM. The present work shows that the retention of timbre shares common features with the retention of pitch, hence supporting the notion that the retention of basic sensory features is an active process that recruits modality-specific brain areas.  相似文献   
999.
1000.

Background

The level of platelet reactivity (PR) inhibition obtained after P2Y12-ADP receptor antagonist loading dose (LD) is associated with the ischemic and bleeding risk following percutaneous coronary intervention (PCI) in acute coronary syndromes (ACS).

Objective

We aimed to evaluate the level of PR inhibition achieved by a 180 mg LD of ticagrelor and the rate of high on-treatment platelet reactivity (HTPR) in ACS patients undergoing PCI.

Methods

We performed a multicentre prospective observational study enrolling ACS patients undergoing PCI. Patients were included if they were admitted for ST-elevation myocardial infarction or non ST-elevation ACS. To assess PR, a VASP index was measured at least 6 and within 24 hours following a 180 mg LD of ticagrelor. HTPR was defined as a VASP index ≥ 50%.

Results

One hundred and fifteen patients were included: 31.3% of STEMI, 49.6% of NSTEMI and 19.1% of unstable angina. Following ticagrelor LD the mean VASP index was 17 ± 14%. However the response to ticagrelor was not uniform with a small inter-individual variability: inter quartile range: 7.6–22.8% and a rate of HTPR of 3.5%. A high number of patients, 65.6%, had a VASP index < 16%. None of the baseline characteristics of the study population was associated with PR. In addition, PR was similar in STEMI, NSTEMI and unstable angina (p = 0.9).

Conclusion

In ACS patients the level of PR inhibition achieved by a 180 mg loading dose of ticagrelor is not uniform and the rate of HTPR is 3.5%. A high proportion of patients exhibited a VASP index < 16%.  相似文献   
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