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991.
A new surgical technique for the treatment of recurrent temporomandibular joint subluxation or dislocation is described. Following a horizontal osteotomy and down-fracture of the articular eminence an inter-positional bovine cartilage xenograft is inserted in order to augment the vertical height of the eminence. The procedure combines simplicity with minimal post-operative morbidity. The increase in eminence height is both predictable and stable.  相似文献   
992.
Plain abdominal radiographs are rarely diagnostic when the patient presents with acute abdominal pain. Emergency physicians, therefore, should be aware of the appropriate indications and limitations of abdominal films in this setting and should be skilled in their interpretation to exclude the rare cases of pneumoperitoneum, pneumobilia, hepatic-portovenous gas, small and large bowel obstruction, toxic megacolon, volvulus and intramural gas.  相似文献   
993.
Deafness mutant mice show no stimulus-related cochlear potentials as well as abnormal electrically-evoked responses recorded from the inferior colliculus. Abnormal spontaneous activity in the auditory periphery could result in abnormal development and/or maintenance of the central auditory pathways. We therefore assessed spontaneous activity of cochlear origin in the central nuclei of the mutants by ablating one cochlea and subsequently using the 2-deoxyglucose (2DG) technique to study metabolic activity. Any asymmetries in labeling in a given nucleus should be due to spontaneous activity in the cochlear nerve on the unoperated side. In control animals (+/dn mice undergoing unilateral cochlea ablation), statistically significant decreased 2DG labeling was observed in the ipsilateral PVCN and AVCN, and contralateral MNTB and IC; all receive primary excitatory input from the ablated ear. No significant differences in labeling between right and left sides were observed in any of the nuclei studied in the mutant animals. These findings suggest that there is no spontaneous activity of cochlear origin in these mutants, even though many cochlear nerve fibers and spiral ganglion cells survive.  相似文献   
994.
In 17 cases the author has removed intraglandular submandibular calculi by an oral route utilizing blunt soft tissue dissection after an incision of the mucosa only. General anesthesia is used and the patient discharged after an overnight stay. No complications were encountered. All patients were back on full diet in 48 hours.  相似文献   
995.
The anatomic principles and operative techniques currently applied to functional endoscopic endonasal surgery have allowed for significant refinements in another approach to regional pathology that uses the operating microscope, newly designed sinus instruments, and a self-retaining nasal speculum system. The main benefits of this method are the superb widefield stereoscopic vision and the distinct freedom to work bimanually. Additionally, direct bipolar cautery of bleeders is afforded while use of the observer tube or video allows for excellent teaching. The precise nature of this surgery affords less fear of serious complications in the treatment of periorbital, paranasal sinus, and parasellar diseases. We describe technical aspects of the surgery and associated complications in 219 patients treated from 1984 to 1987.  相似文献   
996.
We found that thirteen per cent of all head and neck malignomas are malignant lymphomas. In 75% of these cases the Non-Hodgkin type could be found. The major salivary glands were involved by the lymphoma in 55% out of 104 patients. Paraglandular lymph nodes of the parotid gland were affected as well as intraglandular lymph nodes and the lymphoid tissue within the gland proper. The submandibular gland normally shows an involvement only with its paraglandular lymph nodes. Two thirds of the Non-Hodgkin lymphomas located in the salivary glands were low-grade. In case of clinical suspicion of a malignant lymphoma, fine needle biopsy is required for cytological diagnosis. However, surgery is mandatory for histological diagnosis, not as a therapeutic measure.  相似文献   
997.
Monaural loudness balances were performed by eight normal-hearing subjects to determine the effect of click repetition rate on loudness sensation. Click trains of 500 msec duration were matched in loudness to a standard 500 msec 1000 Hz tone burst presented at three reference loudness levels (70, 80, and 90 phons). Click trains were presented at repetition rates of 11, 31, 51, and 91 clicks per sec. It was found that click trains at faster repetition rates required lower intensities for judgments of equal loudness sensation. This finding was attributed to the process of temporal loudness summation. The magnitude and nature of the temporal summation process as well as the influence of the reference loudness level are discussed.  相似文献   
998.
999.
1000.
Occupation and bladder cancer in Spain: a multi-centre case-control study   总被引:5,自引:0,他引:5  
A case-control study on bladder cancer was carried out in four regions of Spain. The study included 497 cases (438 males and 59 females), 583 hospital controls and 530 population controls matched by sex, age and residence. The present paper reports the results of the analyses on occupational history. Among men, an increased risk of bladder cancer was found for textile workers (OR = 1.97, 95% CL 1.2-3.3), mechanics and maintenance workers (OR = 1.86, 95% CL 1.2-2.8), workers in the printing industry (OR = 2.06, 95% CL 1.0-4.3) and for managers (OR = 2.03, 95% CL 1.2-3.5). The risk was highest among those first employed in the textile industry before the age of 25 and prior to 1960. Among mechanics the risk was highest for those who started after the age of 25 and later than 1960. The OR for smokers who had also been employed in one of the high risk occupations was 7.82 (95% CL 4.4-14.0) which is compatible with a multiplicative effect of joint exposure to tobacco and occupational hazards.  相似文献   
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