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101.
We experienced two cases of brain abscess secondary to middle ear cholesteatoma. One, a 61-year-old woman, presented with left otalgia, appetite loss and nausea. The computed tomography obtained on admission revealed a middle ear cholesteatoma. The magnetic resonance image showed the presence of a brain abscess in the cerebellum. The brain abscess was drained and the cholesteatoma was removed using the canal down procedure under general anesthesia. Part of the cholesteatoma invaded the posterior cranial fossa was could not be removed from the otological surgical field. The patient has been under observation as an outpatient for 6 months already and no abnormal signs have been detected.

The other patient, a 55-year-old man, was admitted to our hospital for a detailed examination because he had right otalgia and progressive headache. The examination of spinal fluid obtained by lumbar puncture showed marked elevation of the white blood cells count. Computed tomography revealed a middle ear cholesteatoma. The magnetic resonance image obtained on admission showed an area of low-intensity encapsulated by an area of high-intensity in the right temporal lobe. The abscess was drained and the cholesteatoma was removed using the canal down procedure under general anesthesia. The patient has been under observation for 1 year already and has presented no signs of recurrence.  相似文献   

102.
Arisaema minus is a vulnerable perennial herb species endemic to Japan. We isolated and characterized ten microsatellite loci in this species. The number of alleles per locus ranged from 3 to 28, with an average of 12.8. The observed heterozygosities ranged from 0.472 to 0.861 with an average of 0.703, and the expected heterozygosities ranged from 0.486 to 0.962 with an average of 0.779. The total exclusionary powers of all ten loci, when no parental information existed or when one parent was known, were 0.99940154 and 0.99998730, respectively, indicating the high resolution of these microsatellite loci. This marker set is potentially useful for conservation genetics, reproductive studies, and the development of effective A. minus conservation programs.  相似文献   
103.
104.
In September, 1980, a 57-year-old male, was admitted to hospital for precise examinations to determine if he had Recklinghausen's disease, pneumoconiosis, and a duodenal ulcer. Endoscopy revealed a redness and a shallow depression of the posterior wall of the antrum, and a biopsy of a specimen led to the diagnosis of early gastric cancer, Stage II c. After the examination, the patient did not return to our department again. In May, 1987, however, the man was readmitted to our hospital, suffering from pains in the right back. X-ray and endoscopic findings revealed a gastric cancer with a center depression and a peripheral elevation (II a + II c). Histological findings showed the gastric cancer to be a moderately differentiated tubular adenocarcinoma, with a submucosal invasion that was also seen. This case, uncovered 80 months earlier, represents a rare instance in which an early gastric cancer, accompanied by Recklinghausen's disease, expanded slowly.  相似文献   
105.
Using highly specific antibodies against a chick red-sensitive cone pigment, iodopsin, we investigated the localization of iodopsin in the developing and mature chick retina. The chick retina contains several different photoreceptor types, including a rod, a double cone with a principal and accessory cone, and four different types of single cones. Immunocytochemical observations revealed that outer segments (OS) of one of the single cones (type 1) and both cells of the double cone were strongly immunoreactive to anti-iodopsin antibodies. The Golgi regions and small vesicular structures in the inner segments (IS) of these cells also were intensely stained, indicating a continuous synthesis of iodopsin and its addition to the newly formed cone OS. In the differentiating cones of the developing but immature chick retina, iodopsin immunoreactivity was found at the plasma membranes of both the IS and the terminals (pedicles). This suggests that unidirectional transport of iodopsin to the outer segment may be established during cone differentiation. Immunostaining in the outer plexiform layer (OPL) produced two bands, suggesting that the pedicles of the double cones and type 1 single cones terminate at different positions in this layer. Application of the antibodies to a cell culture system of the chick retina revealed that cells immunoreactive to anti-iodopsin differ slightly in morphology from those reactive with anti-rhodopsin. Since antibodies to iodopsin and rhodopsin stained different types of photoreceptors in the intact chick retina, it will be possible to analyze cell lineage of rods and cones in vitro by use of these antibodies.  相似文献   
106.
The in vivo production of heat shock protein was studied by administration of bacterial lipopolysaccharide (LPS) into mice. Heat shock protein 70 was detected in the extract of adherent peritoneal cells from mice injected intraperitoneally with LPS by using the immunoblotting method. The expression of heat shock protein 70 was found 2 days after injection of LPS and reached its peak 4 days after injection. The intraperitoneal injection of LPS induced the expression of heat shock protein 70, whereas its subcutaneous injection did not. The in vivo production of heat shock protein 70 was inhibited by administration of LPS together with quercetin, an inhibitor of accumulation of heat shock protein 70 mRNA. Tumor necrosis factor alpha enhanced LPS-induced heat shock protein production in vivo. There was a decrease of gamma delta T cells in the peritoneal cavity of mice injected intraperitoneally with LPS. It was suggested that bacterial LPS is a stressful agent which induces the in vivo heat shock protein response, and its administration leads to the production of heat shock protein 70 in peritoneal macrophages.  相似文献   
107.
We report a patient with anterior and posterior inferior cerebellar artery infarction, which manifested as profound deafness, transient vertigo, and minimal cerebellar signs. We suspect that ischaemia of the left internal auditory artery, which originates from the anterior inferior cerebellar artery, caused the deafness and transient vertigo. A small lesion in the middle cerebellar peduncle in the anterior inferior cerebellar artery territory and no lesion in the dentate nucleus in the posterior inferior cerebellar artery territory are thought to explain the minimal cerebellar signs despite the relatively large size of the infarction. Thus a relatively large infarction of the vertebral-basilar territory can manifest as sudden deafness with vertigo. Neuroimaging, including magnetic resonance imaging, is strongly recommended for patients with sudden deafness and vertigo to exclude infarction of the vertebral-basilar artery territory.  相似文献   
108.
109.
1. The dorsal part of medial superior temporal area (MST) has two unique types of visually responsive cells: 1) expansion/contraction cells, which selectively respond to either an expansion or a contraction; and 2) rotation cells, which selectively respond to either a clockwise or a counterclockwise rotation. In addition to selectivity for the mode of motion, both types of cells respond preferentially to movements over a wide field rather than over a small field. With the aim of understanding the underlying mechanisms of these selectivities, we carried out experiments on immobilized monkeys anesthetized with N2O. 2. Expansion/contraction and rotation of a pattern extending over a wide field contain three stimulus factors: 1) the spatial arrangement of different directions of movement, 2) the gradient in the speed of regional movement from the center to the periphery of the stimulus, and 3) the size change of texture components of the pattern in the expansion/contraction and the acceleration of movement of texture components toward the center of the stimulus in the rotation. The contribution of each factor to the activation of the cells was evaluated by comparing the response before and after removing the factor from the stimulus. The moving stimuli that lacked one or two of the factors were produced by the use of a cinematographic animation technique. 3. Withdrawal of the first factor, the spatial arrangement of different directions of movement, reduced the response of both Expansion/contraction and Rotation cells much more severely than either of the other two factors. We concluded that the first factor is far more important for activation than the other two. 4. These results are consistent with the model that Expansion/contraction and Rotation cells receive converging inputs from many directional cells with relatively small receptive fields in different parts of the visual field. Because MST receives strong fiber projections from MT, MT cells are candidates for the input cells. According to the model, if the convergence is organized so that the preferred directions of the input cells are arranged radially, the target cell will be an Expansion/contraction cell; if the input cells are arranged circularly, a Rotation cell will result.  相似文献   
110.
Bile duct carcinoma, which produces clinically recognizable mucus, was defined as "mucus producing bile duct carcinoma", and clinicopathological study was carried out in 7 cases of bile duct carcinoma suitable for the definition. All the tumors arose from the intrahepatic bile duct. There were no tumors arising from the extrahepatic bile duct. Superficially spreading mucosal infiltration of carcinoma was recognized in 6 cases out of 7, and accordingly distinct cholangiography after draining mucus through percutaneous transhepatic cholangio-drainage (PTCD) and percutaneous transhepatic cholangioscopy (PTCS) were indispensable for accurate diagnosis of the extent of carcinoma. The prognosis of patients with mucus producing bile duct carcinoma were almost satisfactory if rational operation had been performed according to accurate diagnosis. On the other hand, since mucus producing bile duct carcinoma frequently has a cystic lesion, the relation to biliary cystadenocarcinoma may become a subject of question. We advocate that biliary cystadenocarcinoma should be included in mucus producing bile duct carcinoma since biliary cystadenocarcinoma originally arises from the intrahepatic bile duct and very rarely from the extrahepatic bile duct. But now the concept of biliary cystadenocarcinoma is equivocal and further investigations will be requested.  相似文献   
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