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31.
Effects of body position on snoring in apneic and nonapneic snorers   总被引:3,自引:0,他引:3  
Nakano H  Ikeda T  Hayashi M  Ohshima E  Onizuka A 《Sleep》2003,26(2):169-172
STUDY OBJECTIVES: The positional dependency of obstructive sleep apnea (OSA) is well known, but objective evidence for the positional effect on snoring is lacking. The aim of this study is to elucidate the effect of body position on snoring, and that of sleep stage as well. DESIGN: Retrospective analysis of the effects of body position and sleep stage on snoring in nonapneic snorers (snorer group) and OSA patients (apneic group). SETTING: A sleep laboratory in a national hospital in Japan. PATIENTS: Seventy-two patients who complained of habitual snoring and underwent overnight polysomnography. INTERVENTIONS: N/A MEASUREMENTS AND RESULTS: In the lateral position, most subjects in the snorer group showed decreased snoring both in time (p = 0.0004) and intensity (p = 0.0003), but subjects in the apneic group showed variable changes. In the apneic group, the positional dependency of snoring (the ratio of lateral value to supine value) was correlated with supine apnea-hypopnea index (AHI), that is, OSA patients with higher supine AHI tended to show increased snoring in the lateral position. AS to the effect of sleep stage, snoring was increased in deeper non-rapid eye movement sleep and decreased in rapid eye movement sleep in a given position. CONCLUSIONS: This study demonstrated that the positional dependency is different between nonapneic snorers and OSA patients. Most of the nonapneic snorers snore less in the lateral position than in the supine position in contrast to OSA patients who often fail to decrease snoring even in the lateral position.  相似文献   
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Induction of recessive lethal mutations by N-ethyl-N-nitrosourea (ENU) was studied for the second chromosome of spermatogonia and spermatozoa in Drosophila melanogaster. ENU (0.03, 0.3, and 1.0 mM) was given to flies by dissolving it in feeding sucrose solution. Since flies are known to show increased avoidance of the feeding solution with increase in ENU concentration, the absorbed doses of ENU by flies were estimated from the previously determined empirical data for relation of ENU concentration in the feeding solution and the intake volumes of the solution by flies as measured indirectly via intake radioactivities of 3H-labeled sucrose added to the solution. When plotted against absorbed doses of ENU, the observed frequencies of recessive lethals showed a linear relationship for induction in spermatozoa but a sigmoidal relationship for induction in spermatogonia. These results suggest that in spermatogonia ENU-induced mutational damage is more repairable in a lower dose range of ENU. Mosaic lethal mutations were induced by ENU but not in spermatogonia.  相似文献   
34.
The stereoregularity of poly(methyl vinyl ketone) (PMVK) was determined by NMR spectra of the polymers. Isotactic and atactic PMVK's were thermally degraded, and thermogravimetric analysis, IR and visible and UV spectroscopy were applied to elucidate the mechanism of the degradation. It was found that the isotactic polymer begins to degrade at lower temperature than the atactic polymer, but its rate becomes lower than that of the atactic polymer at temperatures higher than 320°C. If the two types of polymers were treated at a constant temperature (200°C) for varying times under N2 atmosphere, the isotactic polymer showed a higher degradation rate as determined by thermogravimetric analysis and IR spectroscopy. The isotactic polymer shows a higher tendency to form a monocyclic structure in the heat treatment than the atactic polymer. This is similar to poly(isopropenyl methyl ketone).  相似文献   
35.
The authors report here a case of lymphoepithelial cystic lesion (LECL) of unknown origin in the mediastinum, which is closely related to a signet-ring cell adenocarcinoma. A 73-year-old man presented with a mass as revealed on a chest x-ray. During surgical operation, a solid, well-circumscribed and encapsulated 9 X 9 X 8 cm tumor was isolated from the right anterior mediastinum. This tumor had neither undergone metastasis nor invaded into the surrounding tissue and lymph nodes. Light microscopy revealed the tumor to be a signet-ring cell adenocarcinoma. Clinically, the neoplasm was coupled with an elevation in serum CEA level, which promptly returned to normal values following surgical removal. Immunohistochemistry pointed out that the majority of neoplastic cells stained positive for CEA. In addition, LECL of unknown origin was distinguished at the periphery of the tumor. LECL was characterized by microcysts which were lined by columnar epithelial and surrounded by lymphoid tissue with germinal centers. Transition between the neoplastic cells and benign epithelial cells of LECL was evident, showing that the previously mentioned mediastinal adenocarcinoma may be derived from the epithelial elements of LECL. This paper discusses the histogenesis of LECL.  相似文献   
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Two cases of C cell hyperplasia and one case of C cell carcinoma of the thyroid glands were bilaterally recognized in 11 sheep with experimentally-induced lymphosarcoma. The serum calcium concentration in the C cell carcinoma case was slightly increased above the normal concentration of around 9 mg per dl. Bilateral C cell hyperplasia also developed in the thyroid lobes of the C cell carcinoma case. Immunohistochemically, hyperplastic C cells and tumour cells were positive for calcitonin, calcitonin gene-related peptide, chromogranin A and neurone-specific enolase. No amyloid deposition nor multiple endocrine neoplasia was demonstrated in any of the cases. Ultrastructurally, many secretory granules were observed in the cytoplasm of neoplastic cells constituting the C cell carcinoma and in the hyperplastic C cells.  相似文献   
38.
An autopsy case of recurrent and malignant meningioma is reported. This case was originally typical benign transitional meningioma of the falx, however, the histology of the tumor changed to show malignant features during successive recurrences. At autopsy, the tumor revealed findings consistent with malignant meningioma. One of the most interesting features was the presence of cartilage and giant cells in some parts. Immunohistochemistry showed positive immunoreactivity for S-100 protein in some cartilage and giant cells and for cytokeratin in some giant cells. Multidifferential potential of the meningioma cells was suggested in this case.  相似文献   
39.
One and two-month-old chickens were killed at mid light and mid dark under the experimental photoperiod (LD 12: 12). The pineal glands of the young chickens are composed of parenchymal cells and large follicles, presenting a tubulofollicular arrangement. The sensory-like pinealocytes are pear-shaped and have a cilium with 9 + 0 axial configuration projecting into the lumen. Their cytoplasm has cell organelles, small granulated vesicles about 100 nm in diameter and synaptic ribbons. The concentric lamellar complexes like myelin sheaths are frequently observed in the follicular lumen. The secretory-like supporting cells have irregular-shaped microvilli and some granulated vesicles about 200 nm in diameter in the vicinity of the apical surfaces. Occasionally, a few nerve cells are found in the pineal parenchyma. It was found that the sensory-like pinealocytes of the young chickens have many mitochondria, well-developed Golgi complexes and large lysosomes in solid type in the light period, whereas they have a few cell organelles and somewhat smaller rod-like lysosomes with some vacuoles in the dark period. On the other hand, the sensory-like pinealocytes have more synaptic ribbons in the dark period than in the light period.  相似文献   
40.
Natural killer (NK) cell lymphomas/leukemias are highly aggressive lymphoid malignancies, but little is known about their genomic alterations, and thus there is an urgent need for identification and analysis of NK cell lymphomas/leukemias. Recently, we developed our own array-based comparative genomic hybridization (array CGH) with an average resolution of 1.3 Mb. We performed an array CGH analysis for 27 NK-cell lymphoma/leukemia cases that were classified into two disease groups based on the World Health Organization Classification (10 aggressive NK-cell leukemia cases and 17 extranodal NK/T-cell [NK/T] lymphomas, nasal type). We identified the differences in the genomic alteration patterns of the two groups. The recurrent regions characteristic of the aggressive NK-cell leukemia group compared with those of the extranodal NK/T lymphoma, nasal-type group, were gain of 1q and loss of 7p15.1-p22.3 and 17p13.1. In particular, gain of 1q23.1-24.2 (P = 0.041) and 1q31.3-q44 (P = 0.003-0.047), and loss of 7p15.1-p22.3 (P = 0.012-0.041) and 17p13.1 (P = 0.012) occurred significantly more frequently in the former than in the latter group. Recurrent regions characteristic of the extranodal NK/T lymphoma, nasal-type group, compared with those of the other group were gain of 2q, and loss of 6q16.1-q27, 11q22.3-q23.3, 5p14.1-p14.3, 5q34-q35.3, 1p36.23-p36.33, 2p16.1-p16.3, 4q12, and 4q31.3-q32.1. Our results can be expected to provide further insights into the genetic basis of lymphomagenesis and the clinicopathologic features of NK-cell lymphomas/leukemias.  相似文献   
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