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991.
BackgroundSubstance P (SP) and calcitonin gene-related peptide (CGRP) are released by the nociceptive sensory nerve and are involved in blood flow, pain and inflammation in the nasal mucosa. The purpose of this study was to assess the distribution of the SP and CGRP nerve fibres related to blood supply within human Schneiderian membrane of the maxillary sinus (MS).Material and methodsIn this study, the MS from Japanese cadavers was examined by whole-mount immunohistochemistry. Human male cadavers (ranging in age from 80 to 90 years) were used in this study.ResultsSP- and CGRP-positive fibres were found around large vessels of the medialis superior alveolar branches and also within the floor region of the MS. The floor region of the MS was composed of complex branches of these fibres.ConclusionOur results give useful information for surgical sinus floor elevation in this region of the MS. These anatomical features may assist in the execution of a successful surgical procedure.  相似文献   
992.
In normal sleep, cortical EEG activity is influenced by the balance in the activities of subcortical neurons in relation to the cyclic changes of sleep states. As well, jaw motor excitability is altered under the activity of sleep regulatory mechanism. Transient arousals (e.g., micro-arousal) are associated with a brief change of cortical activity and an increase of jaw motor activity. During this period, various types of jaw motor activities are occasionally found to occur, with either non-specific or specific patterns such as rhythmic activations. Exaggeration of the jaw motor activities during sleep can be seen in patients with sleep bruxism. Although cortical activity reflects arousal level and is correlated with the activity level of jaw muscles during sleep, it remains to be investigated whether or not cortex plays one of the sources of descending excitatory drive shaping a variety of jaw motor activities.  相似文献   
993.
ABSTRACT: This report assessed the bone-implant contact (BIC) and interthread bone density (BD) of 3 titanium implant interfaces retrieved from a mandible that was reconstructed with a vascularized osteocutaneous scapular graft and revised with multidirectional distraction osteogenesis before implant placement. The BICs and BDs were 86.9% and 92.8%, 67.3% and 80.6%, and 61.3% and 77.1%, respectively, for each of the implants in the graft that were revised 0 times, 1 time, and 2 times with distractions, respectively. The average rates of the BIC and BD of these 3 implants were 73.9% and 84.7%, respectively. The present assessment indicates that there was sufficient osseointegration of the implants in the vascularized scapular bone graft even after revision with distraction osteogenesis.  相似文献   
994.
Maeda FY  Cortez C  Alves RM  Yoshida N 《Acta tropica》2012,121(2):141-147
Protozoan parasites of the genus Trypanosoma can infect virtually all mammalian species. Within this genus, Trypanosoma dionisii from bats and Trypanosoma cruzi that causes Chagas' disease, belonging to the subgenus Schizotrypanum, can invade mammalian cells. The mechanisms of cell invasion by T. dionisii are poorly understood. To address that question, metacyclic trypomastigotes (MT) and human epithelial HeLa cells were used. Similarly to genetically divergent T. cruzi strains G (TcI) and CL (TcVI), associated, respectively with marsupial and human infections, T. dionisii infectivity increased under nutritional stress, a condition that induces host cell lysosome exocytosis required for parasite internalization. For efficient internalization, T. dionisii depended on MT protein tyrosine kinase (PTK) and Ca(2+) mobilization from acidocalcisomes, whereas T. cruzi strains also relied on phosphatidylinositol 3-kinase (PI3K), protein kinase C (PKC) and Ca(2+) released from thapsigargin-sensitive compartments. T. dionisii-induced signaling in host cells implicated PKC and Ca(2+) mobilized from thapsigargin-sensitive stores, like T. cruzi, but without PI3K involvement. Unlike T. cruzi, T. dionisii metacyclic forms did not use l-proline as source of energy required for internalization. Molecules related to T. cruzi surface glycoproteins involved in MT-host cell interaction were undetectable in T. dionisii. The difference in the surface profile of the two species was also inferred from the susceptibility of T. dionisii metacyclic forms to complement-mediated lysis, as opposed to complete resistance of T. cruzi. In summary, the two Trypanosoma species display distinct surface profiles but invade host cells through a common mechanism involving lysosome mobilization to the site of parasite entry.  相似文献   
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Taeniasis refers to the infection with adult tapeworms of Taenia spp. in the upper small intestine of humans, which is also a cause of cysticercosis infection in either both humans and/or animals. Currently the most commonly applied anthelminthics for treatment of taeniasis are praziquantel and niclosamide. Praziquantel is very effective, but has the risk of induction of epileptic seizures or convulsions in carriers with asymptomatic concurrent neurocysticercosis. In contrast, niclosamide is safe and effective, but is not readily available in many endemic countries including China. In the current community-based study, we assessed the curative effect of either pumpkin seeds or areca nut extract alone in taeniasis, and also looked at synergistic effects of these two herb drugs on tapeworms. In the study group with the pumpkin seed/areca nut extract treatment, 91 (79.1%) of 115 suspected taeniasis cases (with a history of expulsion of proglottids within the previous one year) released whole tapeworms, four (3.5%) expelled incomplete strobila, and no tapeworms or proglottids were recovered in the remaining 20 cases. In these 115 persons, 45 were confirmed as taeniasis before treatment by microscopy and/or coproPCR. Forty (88.9%) of 45 confirmed cases eliminated intact worms following treatment. The mean time period for complete elimination of tapeworms in 91 taeniasis cases was 2h (range 20min to 8h 30min), and 89.0% (81) of 91 patients discharged intact worms within 3h after drug administration. In Control Group A with treatment of pumpkin seeds alone, 75.0% (9/12) of confirmed taeniasis cases expelled whole tapeworms, but the mean time period for complete elimination was about 14h 10min (range 3h 20min to 21h 20min), which was much longer than that (2h) for the study group, whereas in Control Group B treated with areca nut extract alone, only 63.6% (7/11) of taeniasis cases discharged whole tapeworms, and the mean time period was 6h 27min (range 1-22h). Mild side effects included nausea and dizziness in about 46.3% of patients with the pumpkin seeds/areca nut extract treatment, but all discomforts were transient and well tolerated. In conclusion, a synergistic effect of pumpkin seed and areca nut extract on Taenia spp. tapeworms was confirmed in the current study, primarily in producing an increased rate of effect on tapeworm expulsion (average time 2h for combination vs 6-21h for individual extracts). The pumpkin seed/areca combined treatment was indicated to be safe and highly effective (89%) for human taeniasis.  相似文献   
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