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41.
A rare case of high-grade surface osteosarcoma of the left ilum is reported. Trephine biopsy performed on a 31-year-old woman suffering from a huge tumor of the left buttock revealed high-grade osteosarcoma, and hemipel-vectomy was undertaken. The surgical specimen showed that the tumor was present on the surface of the left ilium. Ten months after the operation, the patient died of brain metastasis. From these results, we considered this case to be one of high-grade surface osteosarcoma. ACTA PATHOL JPN 38: 235 -240, 1988.  相似文献   
42.
A rare case of primary pulmonary synovial sarcoma with polypoid endobronchial growth in a 42-year-old Japanese woman is described. Left upper sleeve lobectomy was performed for the polypoid tumor measuring 2.5 cm in the left major bronchus and the patient was treated with adjuvant chemotherapy. Three years later, a recurrent tumor was discovered. Microscopically, this tumor was characterized by a proliferation of oval to spindle-shaped cells arranged in sheets and fascicles and covered by the thin normal bronchial epithelium. Immunohistochemically, tumor cells were positive for vimentin, and focally positive for pancytokeratin recognized by AE1/AE3, cytokeratin 7 and epithelial membrane antigen. A chimera gene, SYT-SSX1, was detected. Recently, primary pulmonary synovial sarcoma is an increasingly recognized clinical entity; however, most of these tumors present as a parenchymal mass. The present case is a unique example of primary synovial sarcoma of endobronchial polypoid type. This case suggests that pulmonary synovial sarcoma might originate from bronchial submucosal stromal tissue.  相似文献   
43.
44.
A device for measuring ambulatory activity in mice was developed. The device consisted of a plastic case, a bed plate, a step board (as a detector) and a calculator (as a recorder). A 2.2 cm width section was cut out from the middle of the case bottom in the direction of the minor axis and a step board, a width of 2 cm, was placed in the opening. A short bolt was screwed into one end of the step board and the head of the bolt was placed on the equal key of the calculator. The calculator counted the number of times the mouse stood on the step board. The validity of the device was demonstrated by measuring the effect of methamphetamine (1-4 mg/kg) on the ambulatory activity in mice.  相似文献   
45.
Summary The role of oral and facial sensory receptors in the control of masticatory muscle activities was assessed from the effect of acute deafferentiation on cortically induced rhythmic jaw movements (CRJMs) in anesthetized rabbits. When a thin polyurethane-foam strip (1.5, 2.5 or 3.5 mm thick) was placed between opposing molars during CRJMs, masseteric activities were facilitated in association with an increase in the medial excursion of the mandible during the power phase. The effects varied with the pattern of CRJMs, and the rate of facilitation was greater for small circular movements than for the crescent-shaped movements. Furthermore, the response of the masseter muscle was greater in the anterior half of the muscle, where muscle spindles are most dense, than in its posterior half. It was also demonstrated that the response increased with an increase in the thickness of the test strip. In contrast, the activities of the jaw-opening muscle were not affected significantly. The duration of masseteric bursts increased during application of the test strip and the chewing rhythm tended to slow down. However, the latter effect was not significant. After locally anesthetizing the maxillary and inferior alveolar nerves, the facultative responses of the masseter muscle to the test strip was greatly reduced but not completely abolished. Lesioning of the mesencephalic trigeminal nucleus (Mes V) where the primary ganglion cells of muscle spindle afferents from jaw-closing muscles and some periodontal afferents are located, also reduced the facilitative effects. Similar results were obtained in the animals with the kainic acid injections into the Mes V 1 week before electrical lesioning of this nucleus. In these animals the effects of electrical lesioning of the Mes V could be attributed to the loss of muscle receptor afferents since the neurons in the vicinity of the Mes V were destroyed and replaced by glial cells, whereas the Mes V neurons are resistant to kainic acid. When electrical lesioning of the Mes V and sectioning of the maxillary and inferior alveolar nerves were combined in animals with a kainic acid injection into the Mes V, the response of the masseter muscle to application of the strip was almost completely abolished. From these findings, we conclude that both periodontal receptors and muscle spindles are primarily responsible for the facilitation of jaw-closing muscle activities. Furthermore, it is suggested that the transcortical loop may not be the only path producing this facilitation since similar effects were induced in animals with ablation of the cortical masticatory area (CMA), when the test strip was placed between the molars during rhythmic jaw movements induced by pyramidal tract stimulation.  相似文献   
46.
The purpose of this study was to explore how the muscles which control postural body segments are activated during bilateral isometric ramp pushes exerted with the upper limbs by seated subjects. The paradigm under study presents the advantage that the subject is in a quasi-static posture, and since upper limbs are stretched out, the dynamic phenomena, which might occur, can only originate from the rest of the body, which means from the postural chain. A dynamometer was used to measure the horizontal force, Fx, exerted on the bar, and a custom-designed force-plate was used to measure global reaction forces (Rx) and displacement of the centre of pressure (Xp) along the antero-posterior axis. Electromyograms (EMGs) were picked up by bipolar surface electrodes from 14 muscles crossing the lower limb, pelvis, trunk and upper limb joints. It was shown that transient push efforts require monotonous EMG increase in postural as well as in focal muscles. The EMG sequence starts with the postural muscles and ends with the focal ones. The postural EMG sequence is anticipatory. It is concluded that the EMG sequence is programmed according to the task parameters, and that its role is to counteract in advance the perturbing effect of the effort, in order to allow the effort to be performed efficiently. It is suggested that excitation between the postural muscles is distributed according to their biomechanical role in relation to the supports.  相似文献   
47.
A clinical trial of ceftizoxime suppositories (CZX-S) was performed to evaluate the therapeutic effectiveness in children with bacterial infection. The subjects were 10 children comprising 4 with pneumonia, 3 with lacunar tonsillitis, 2 with pharyngitis, and 1 with UTI. They were given 1 suppository containing either 125 mg or 250 mg of CZX 2 to 4 times a day. The daily per kg body weight dose ranged from 17.1 to 60.0 mg. The result was "markedly effective" in 3, "effective" in 6, and "failure" was recorded in 1. Bacteriologically, successful eradication of causative organisms was confirmed in all the 4 children who underwent the test. No clinical side effects were observed. The only laboratory test abnormality recorded in a single patient was eosinophilia, which was not definitely ascribable to CZX-S. In conclusion, CZX-S have proved to be a clinically safe and effective antibiotic preparation in infantile infection, even in children whose treatment with conventional antibiotics is associated with difficulties.  相似文献   
48.
Rats with bladder tumor induced by BBN were treated by intravesical instillation of 0.8 mg of (2"R)-4'-O-tetrahydropyranyladriamycin (THP) (9 rats) or adriamycin (ADM) (8 rats) dissolved in 0.2 ml of distilled water. Thirty minutes later, the bladder was removed surgically. Rats without the tumor received the same treatment of THP (8 rats) or ADM (9 rats). THP and ADM infiltrations to the normal bladder tissue and the tumor were estimated by the use of the photonic microscope system, since both drugs were known to emit characteristic fluorescence. It was found that infiltration of THP to the tumor tissue was more prominent in amounts and deeper than that of ADM, while smaller amounts of THP infiltrated into the normal mucosa compared to ADM. The fact might explain the clinical finding that THP instilled intravesically in half a concentration of ADM showed the same effect on the tumor as ADM. Subsequently, tissue concentrations of THP and ADM were estimated by high performance liquid chromatography. Either THP or ADM was instilled intravesically for 30 minutes to 6 rats with bladder tumor. Similarly, either THP or ADM was instilled in 5 rats without the tumors. Contrary to the result of the photonic microscope system, the tissue concentration of THP was not different from that of ADM not only in the tumor tissues but also in the normal bladder ones. Furthermore, the tissue concentration of both drugs in the normal bladder was higher than that in the bladder tumor.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
49.
The pharmacokinetics of polychlorinated dibenzofurans (PCDFs) and polychlorinated biphenyls (PCBs) in humans was studied by monitoring the blood concentrations of individuals who ingested a contaminated rice oil in Japan (yusho) in 1968 and in Taiwan (yu-cheng) in 1979. Sixteen yusho patients were followed from 1982 to 1990 and three yu-cheng individuals from 1980 to 1989. From the three yucheng patients, blood lipid values for the two persistent toxic congeners, 2,3,4,7,8-pentachlorodibenzofuran (PnCDF) and 1,2,3,4,7,8-hexachlorodibenzofuran (HxCDF), varied from 50 g/kg at first sampling to about 1 g/kg at last sampling corresponding to half-lives for elimination (t1/2) of 2-21/2 years. The blood lipid values for the same PCDF congeners in yusho patients varied from 5 g/kg down to 0.1 g/kg. The calculated t1/2 were more variable with median values closer to 10 years. Planar PCBs #126 and #169 were present at lower concentrations than the PCDFs. For seven of the other PCB congeners, half-lives for elimination in the yu-cheng individuals varied from 1.2 up to 4.6 yr depending on the degree of chlorination. For the yusho patients, the elimination for the PCBs was longer. These results show that clearance of the toxic PCDFs and PCBs in humans is non-linear with faster elimination at higher exposure followed by slower decreases as background levels are approached. Such a clearance pattern can best be explained by a two compartment liver and fat pharmacokinetic model.  相似文献   
50.
Malignant tumors of the paranasal sinuses are rare: about 80% are found in the maxillary sinus123. The presence of dense radiopaque masses in combination with destruction of the bone margins suggests osteosarcoma or aspergillosis4 rather than carcinoma. We present a unique mucoepidermoid carcinoma of the maxillary antrum containing new bone formation and discuss the differential diagnosis.  相似文献   
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