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1.
Ameloblastic carcinoma (AC) is an aggressive malignant epithelial odontogenic tumor. It may appear de novo or originate from a pre-existing ameloblastoma or odontogenic cyst. To our knowledge, an AC that originates from the anterior skull base has not been reported before in the English literature. We report a case of an AC that originated from the anterior skull base and invaded the dura of the anterior fossa and discuss its clinical course and treatment.  相似文献   
2.
Although considered a safe procedure, operative hysteroscopy has been reported to result in serious and even fatal complications. A fatal outcome is described after operative hysteroscopy. The attending team made a diagnosis of massive air embolism. However, HBO therapy, which is the specific treatment for air embolism, yielded only transient improvement. The pathologist's diagnosis on autopsy was anaphylaxis. These two complications must be borne in mind during the procedure, and a contingency plan developed for dealing with them should they arise.  相似文献   
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4.
To characterize the effectiveness of a local ordinance that restricts smoking in restaurants to one third of the seating area, this study made simultaneous measurements of two markers of environmental tobacco smoke, respirable suspended particles and nicotine, in the smoking and no-smoking sections of seven restaurants. The mean concentrations of respirable suspended particles and nicotine were 40% and 65% lower, respectively, in the no-smoking than in the smoking sections, indicating substantial but not complete protection against exposure.  相似文献   
5.
Photic evoked responses were recorded from the striate cortex of Long-Evans hooded intact, monocular visual deprivation (MD) and MD treated with NGF rats. The averaged visual evoked responses (AVER) were obtained from both hemispheres and provided comparison after binocular photic stimuli between the contralateral and the ipsilateral striate cortex with relation to the MD eye. One month of monocular visual deprivation at the critical period of development resulted in marked reduction of the amplitudes of AVER components as compared to the control recordings (P < 0.001). These changes of the AVER could be prevented by NGF infusion to lateral ventricle at the dosage of 2.0–2.4 μg/day for four weeks during the monocular deprivation. In conclusion, the change of AVER amplitudes induced by monocular visual deprivation during the critical period of development can be prevented by NGF infusion to lateral ventricle.  相似文献   
6.
The clinical specimens received from patients hospitalized in Department of Thoracic Surgery between 1997 and 2001 were microbiologically examined. The main specimen for microbiological examination was pleural fluid (median 34%). The frequency of specimens from bronchial tree increased significantly (from 4% to 26%) with concurrent decrease of sputum (from 29% to 6%). Among isolated pathogens, Gram negative rods were the most frequent (median 48%) and Pseudomonas sp. was the main pathogen among them. Occurrence of staphylococci was median 22% and Staphylococcus aureus, with a little decrease in analyzed period, was still the main Gram positive pathogen. Simultaneously the occurrence of MRSA in the last three years dropped three times. The number of isolations of yeasts have risen from 5.8% to 10.3%.  相似文献   
7.
Myoepithelial carcinoma in the nasopharynx: an unusual localization   总被引:1,自引:0,他引:1  
Myoepithelial carcinoma is an extremely rare, malignant epithelial tumor which is usually encountered in the parotid region. In this report, a myoepithelial carcinoma arising from a minor salivary gland in the nasopharynx is presented, along with a discussion of the clinical, histopathological and immunocytochemical characteristics of this rare disorder. Larger clinical series and longer follow-up periods are needed in order to establish the best therapy option for these patients.  相似文献   
8.
A population-based case-control study of lung cancer was performed in New Mexico to explain the differing patterns of lung cancer occurrence in the state's "Hispanic" Whites and other Whites. From 1980 through 1982, interviews were completed with 521 cases and 769 controls. In the male controls, the prevalence of current and previous cigarette usage was similar in the two ethnic groups, but Hispanics smoked fewer cigarettes daily. In the female controls, a lower percentage of Hispanics had ever smoked and their usual consumption was less than that of other White women. Older Hispanic female smokers had used hand-rolled cigarettes for an average of 8.8 years, whereas other White women of the same age had used this type for less than one-half year. Both stratified and multiple logistic analysis showed comparable risks of lung cancer in Hispanic White and other White smokers. There was no evidence of interaction between ethnicity and cigarette smoking. These analyses imply that the differences in lung cancer incidence between New Mexico's Hispanic Whites and other Whites are largely explained by the patterns of cigarette smoking of these two groups.  相似文献   
9.
Lung cancer and occupation in New Mexico   总被引:6,自引:0,他引:6  
The association between occupation and lung cancer risk was examined in a population-based, case-control study of 506 patients (333 males and 173 females) and 771 control (499 males and 272 females) subjects in New Mexico. A personal interview was used to obtain lifetime occupational and smoking histories and self-reported history of exposures to specific agents. High-risk jobs were identified in advance of data analysis and linked with industrial and occupational codes for hypothesis testing. For females, lung cancer risk was not associated with employment history, but power was limited. For males, elevated risks were found for the uranium mining industry [odds ratio (OR) = 1.9; 95% confidence internal (CI) = 0.8-4.9], underground miners (OR = 2.1; 95% CI = 1.1-3.7), painters (OR = 2.7; 95% CI = 0.8-8.9), and welders (OR = 3.2; 95% CI = 1.4-7.4). For self-reported exposure to any of 18 agents, only the OR for exposure to "other metals" was elevated. The population attributable risk in males was estimated as 14% for employment in any high-risk industry or occupation with an OR above 1 in this study.  相似文献   
10.
Histopathology of lung cancer in New Mexico, 1970-72 and 1980-81   总被引:1,自引:0,他引:1  
In conjunction with a population-based case-control study of lung cancer in New Mexico, the histopathology of cases diagnosed during 1980 and 1981 and during 1970-72 was reviewed. Adequate histologic or cytologic material was obtained for 725 cases, with 308 during 1970-72 and 417 during 1980-81. The light microscopic histologic type was classified on the basis of review by 2 pathologists. No significant differences were found in the histologic-type distributions in Hispanics and non-Hispanic whites. In males, the distributions of histologic types were similar in the two time periods, but in non-Hispanic white women the proportion of adenocarcinoma declined during 1980-81 as the proportion of small cell carcinoma increased. The panel classification was compared with that recorded by the New Mexico Tumor Registry. Overall agreement was 52.1% for 1970-72 and increased to 65.2% for 1980-81. The discrepancies between the two classifications were largest for the categories of large cell undifferentiated carcinoma and "other malignancy."  相似文献   
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