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31.
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Oded Cohen Hadar Rotem Betito Meital Adi Yael Shapira-Galitz Doron Halperin Yonatan Lahav Meir Warman 《Clinical anatomy (New York, N.Y.)》2020,33(7):1019-1024
The relation between pharyngeal tonsil and the bony nasopharynx determines the nasopharyngeal airway patency. Despite its importance, an anatomical study utilizing advanced imaging has not been conducted. The aim of the study was to evaluate the pharyngeal tonsil and bony nasopharynx depth and their ratio (adenoid-nasopharyngeal ratio [ANR]) with relation to sex and age in the general pediatric population. After excluding reported history of adenoidectomy, acute upper airway illness, allergy, and poor quality, 200 randomly selected head computed tomographies (CTs) of children were evaluated. CTs were divided into five age groups (0–5, 5.1–8, 8.1–11, 11.1–14, and 14.1–17 years). For each CT scan, the pharyngeal tonsil, bony nasopharynx and ANR values were calculated. A significant difference was found in the bony nasopharynx and pharyngeal tonsil depth between the five age subgroups (P < 0.001). Both bony nasopharynx and pharyngeal tonsil depth significantly increased between the age groups of 0–5 years to 5.1–8 years (4.17 mm increase, P < 0.001 and 3.47 mm increase, P < 0.009, respectively). The pharyngeal tonsil depth gradually decreases following the age of 8 years. No difference was found between age groups beyond age of eight for both the pharyngeal tonsil tissue and the bony nasopharynx. The ANR has an upward trend in the age group of 5.1–8 years. No sexual predilection was found. The bony nasopharynx and the pharyngeal tonsil tissue both grow during childhood. Different growth rates result in the narrowest airway in the age group of 5.1–8 years (ANR peak). These growth curves should be taken under consideration when treating pediatric pharyngeal tonsil hypertrophy. Clin. Anat., 33:1019–1024, 2020. © 2019 Wiley Periodicals, Inc. 相似文献
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Oded Cohen Meir Warman Moran Fried Hagit Shoffel-Havakuk Meital Adi Doron Halperin Yonatan Lahav 《Auris, nasus, larynx》2018,45(1):96-102
Objective
To study volume characteristics of the maxillary, sphenoid and frontal sinuses among healthy Caucasians adults, using computed tomography (CT) scans.Methods
A retrospective, case series study in a single academic center, CT scans of 201 consecutive adult subjects, performed between January and September 2014, were reviewed for the volume and dimensions of the paranasal sinuses. Patients with documented sinus pathology or lack of pneumatization were excluded.The study population was subdivided by gender and age (50 men age 25–64; 51 men age ≥65; 50 women age 25–64, and 50 women age ≥65).Results
The mean volume of maxillary, sphenoid and frontal sinuses in the four groups were 12.75 ± 4.38 cc; 4.00 ± 1.99 cc and 2.92 ± 2.57 cc, respectively. In both genders, older patients demonstrated a significantly lower volume of the maxillary and sphenoid sinuses (14.81 ± 3.96 cc vs. 11.82 ± 4.28 cc and 4.84 ± 1.97 vs. 3.84 ± 1.89 cc respectively; p < 0.001). No age related difference was found in the frontal sinus. Males had significantly larger sinus volumes than females (p < 0.001): maxillary 14.38±(4.64) vs. 12.23 ± (3.82) cc, sphenoid 4.74 ± (2.06) vs. 3.55 ± (1.73) cc, frontal 3.74 ± (2.97) vs. 3.21 ± (2.79) cc. No synergistic effect of age and gender was found.Conclusion
Volumes of the paranasal sinuses correlates with age and gender. Age related volume degeneration is expected in the maxillary and sphenoid sinuses. This volume reduction may influence future surgical and therapeutic approaches in the geriatric population. 相似文献35.
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It is well‐established that whether the information will be remembered or not depends on the extent to which the learning context is reinstated during post‐encoding rest and/or at retrieval. It has yet to be determined, however, if the fundamental importance of contextual reinstatement to memory extends to periods of spontaneous neurocognitive activity prior to learning. We thus asked whether memory performance can be predicted by the extent to which spontaneous pre‐encoding neural patterns resemble patterns elicited during encoding. Individuals studied and retrieved lists of words while undergoing fMRI‐scanning. Multivoxel hippocampal patterns during resting periods prior to encoding resembled hippocampal patterns at encoding most strongly for items that were subsequently remembered. Furthermore, across subjects, the magnitude of similarity correlated with a behavioral measure of episodic recall. The results indicate that the neural context before learning is an important determinant of memory. 相似文献
39.
Long‐term survival following the development of heart failure in an elderly hypertensive population
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40.
Kupchik YM Rashkovan G Ohana L Keren-Raifman T Dascal N Parnas H Parnas I 《Proceedings of the National Academy of Sciences of the United States of America》2008,105(11):4435-4440
Ca(2+) is essential for physiological depolarization-evoked synchronous neurotransmitter release. But, whether Ca(2+) influx or another factor controls release initiation is still under debate. The time course of ACh release is controlled by a presynaptic inhibitory G protein-coupled autoreceptor (GPCR), whose agonist-binding affinity is voltage-sensitive. However, the relevance of this property for release control is not known. To resolve this question, we used pertussis toxin (PTX), which uncouples GPCR from its G(i/o) and in turn reduces the affinity of GPCR toward its agonist. We show that PTX enhances ACh and glutamate release (in mice and crayfish, respectively) and, most importantly, alters the time course of release without affecting Ca(2+) currents. These effects are not mediated by G(beta)gamma because its microinjection into the presynaptic terminal did not alter the time course of release. Also, PTX reduces the association of the GPCR with the exocytotic machinery, and this association is restored by the addition of agonist. We offer the following mechanism for control of initiation and termination of physiological depolarization-evoked transmitter release. At rest, release is under tonic block achieved by the transmitter-bound high-affinity presynaptic GPCR interacting with the exocytotic machinery. Upon depolarization, the GPCR uncouples from its G protein and consequently shifts to a low-affinity state toward the transmitter. The transmitter dissociates, the unbound GPCR detaches from the exocytotic machinery, and the tonic block is alleviated. The free machinery, together with Ca(2+) that had already entered, initiates release. Release terminates when the reverse occurs upon repolarization. 相似文献