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101.
There seems to be a resistance of patients and physicians towards aggressive diagnostic evaluation of the symptoms of lung cancer in young people. We here review nine series of young patients with primary lung cancer. Patients below 40 years of age represent between 1.2 and 5% of the total lung cancer population. The distribution of sex and histopathologic findings is different, there being more women, fewer cases of squamous cell and more cases of small anaplastic and adenocarcinoma in the young group. Between 87 and 96% are smokers. There is a delay from the debut of symptoms to the first contact with a general physician of 2.4 to 10.8 months. There is a wide variation concerning tendency to operate with a frequency of curative resection of between 15 and 57%. Based on the survival of young patients who are treated by curative surgical resection, the outcome of surgical treatment for young patients does not differ from the general experience concerning resection in patients of all ages. Young patients who are found inoperable have worse survival than the older patients. Seventy to 90%, more than in the group of patients of all ages, have stadium II or III at the time of diagnosis. In conclusion, physicians should be aggressive with respect to the diagnostic evaluation even of young patients with symptoms suggestive of lung cancer. 相似文献
102.
Michael L. Matthews 《Accident; analysis and prevention》1982,14(6):431-438
An observational survey was conducted on 11.961 vehicles in Southern Ontario to determine car driver seat belt use. Major variables included geographical location, road type. sex of driver and size of vehicle. Overall usage rate was 48.6% and was higher in the large city and higher for expressways than non-expressways. Seat belt use was inversely related to car size across all survey sites and geographical locations. Sex differences in usage rates were found to interact with variables of geographical location and road type. 相似文献
103.
104.
The deans and departmental chairs of the 22 schools of public health were asked in 1981 to list all psychologists holding full-time faculty appointments and the names of courses with a substantial behavioral/psychological content. Responses were received from 98% of the departments. The psychologists were then sent a survey concerning their backgrounds, job responsibilities, and satisfaction/dissatisfaction with their positions. There was an 80% response rate. Psychologists accounted for 5.7% of the approximately 1,300 full-time faculty in schools of public health. Psychologists represented a larger percentage of the faculty in departments of behavioral science than in departments of epidemiology, biostatistics, environmental health, and so forth. Public health psychologists were active researchers and publishers, with average totals of 2.5 articles and 26.9 citations for a three-year period. The primary advantages of employment in a school of public health had to do with an appreciation of the public health perspective, an interdisciplinary orientation, and research opportunities. The primary dissatisfactions cited were financial insecurity, isolation from psychology, and lack of appreciation among public health colleagues of the contribution of psychology to public health. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
105.
106.
Thorium oxide and uranium oxide pellet fuel development activities leading to a process fohd fabrication of high density, homogeneous fuel pellets are described. Conventional dry ball-milling was used to comminute commercially available powders. After separate milling, these ThO2 -UO2 mixtures were co-milled, pressed, and sintered to 95 % of theoretical density with a homogeneous distribution of the components. An intimate mix of highly active powders promotes solid solution formation and yields high density pellets. 相似文献
107.
A case of right atrial myxoma is described. The patient had vague and variable symptoms and it was not until five years after first presentation that she had developed clinical and electrocardiographic evidence of right atrial hypertrophy, and angiocardiographic evidence of a fist-sized myxoma which was subsequently removed surgically. 相似文献
108.
Appearance-based face recognition and light-fields 总被引:7,自引:0,他引:7
Gross R Matthews I Baker S 《IEEE transactions on pattern analysis and machine intelligence》2004,26(4):449-465
Arguably the most important decision to be made when developing an object recognition algorithm is selecting the scene measurements or features on which to base the algorithm. In appearance-based object recognition, the features are chosen to be the pixel intensity values in an image of the object. These pixel intensities correspond directly to the radiance of light emitted from the object along certain rays in space. The set of all such radiance values over all possible rays is known as the plenoptic function or light-field. In this paper, we develop a theory of appearance-based object recognition from light-fields. This theory leads directly to an algorithm for face recognition across pose that uses as many images of the face as are available, from one upwards. All of the pixels, whichever image they come from, are treated equally and used to estimate the (eigen) light-field of the object. The eigen light-field is then used as the set of features on which to base recognition, analogously to how the pixel intensities are used in appearance-based face and object recognition. 相似文献
109.
Grondin Y Matthews K McEntee M Rainford L Casey M Tonra M Al-Qattan E McCrudden T Foley M Brennan PC 《Radiation protection dosimetry》2004,108(2):123-132
This work, using an adult anthropomorphic phantom, aimed to establish an optimised technique for ladies of child-bearing age undergoing antero-posterior (AP) pelvis and AP and lateral lumbar spine examinations. Phase one of the work involved introducing the following dose-reducing measures individually: increased kVp, increased focus-film distances, a carbon fibre cassette, a faster film/screen combination. The second phase established an optimised technique based on a combination of the parameters listed above. Radiation dose was measured using thermoluminescent dosimeters and image quality was evaluated using anatomical criteria. All dose-reducing methods were compared with a standard technique, currently being used in a Dublin hospital. The results demonstrated that the optimised procedure reduced effective dose by 77, 62 and 66% for AP pelvis and AP and lateral lumbar spine respectively (p < 0.05) compared with the standard technique, with no significant changes in image quality. Dose-reducing measures used in combination offer substantial potential for optimisation of radiological procedures. 相似文献
110.