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81.
The squamous cancers of the oropharynx in 384 patients were staged according to a T and N system. Three hundred seventy-one of them were treated for cure at a time when modern surgical and radiotherapeutic technics were available. The patient records were analyzed in regard to five year survival, factors influencing treatment failure, and the effect of new primary cancers. Failure to eradicate the cancer at the primary site remains the largest reason for the patients' demise, but as aggressive local and regional treatment becomes more successful, greater numbers of patients survive only to become victims of distant metastases and second primary cancers. 相似文献
82.
Thirty-seven patients with a presumptive diagnosis of dementia of the Alzheimer type were divided into presenile and senile groups according to the age at which they first received a clinical diagnosis. Although there were no differences in mental status, dementia rating, or chronicity of disease, multivariate analyses of WAIS subtests revealed the presenile subjects to be relatively impaired on Performance subtests. Univariate tests of Verbal, Performance, and Full Scale IQ measures were significantly lower in the presenile group. There was no group effect detected for Digits forward, adjusted for age differences based upon performance of 40 age-matched controls, while the presenile group performed significantly more poorly on backward span. Further, significant differences were detected for an embedded figure task, as well as graphomotor speed. These data suggest that patients who develop a degenerative dementia during the presenile period are more impaired than their senile counterparts on age-adjusted measures of sustained concentration and mental tracking. 相似文献
83.
H.H. Bunchman II MD Ted T. Huang MD D.L. Larson MD S.R. Lewis MD 《American journal of surgery》1975,130(6):700-703
Two hundred patients with neck burns were analyzed to determine the incidence of contractures. It was found that only 8 per cent of patients with second degree burns had contractures, all of which were mild. Both the overall incidence of cervical contractures in patients with third degree neck burns and their severity can be decreased by the use of a custom-formed isoprene splint. Splinting should begin as soon as possible after the burn and continue until scar maturation is complete. 相似文献
84.
Visual threshold for stroboscope test flashes was measured during saccadic eye movements over various backgrounds and compared with measures obtained during eye fixation when the same backgrounds were “saccadically” displaced. Amount and time course of threshold change in the two situations compared well, suggesting no necessity for corollary discharge or other oculomotor interference with primary visual processes during eye movement. No significant threshold rise took place during saccades in the dark. Diffuse test flashes and small well focused flashes were affected differently by specific background conditions. Diffuse flashes were perceived with more difficulty during a saccade over a contour-free background than well focused, punctate stimuli. On the other hand, contours in the background raised saccadic thresholds for small stimuli much more than for diffuse test flashes. All threshold changes occurring during saccades were accentuated by increasing the background luminance. 相似文献
85.
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87.
Implicit functions of a health care system which are often omitted or improperly emphasized are the study and promotion of individual health. This situation stems from the fact that health care systems are primarily based on the concept of disease, while the attributes of health (positive health) have not been investigated and objectively defined. However, an operational definition of the elusive concept of health appears possible today and is discussed in this paper. If the hypotheses that health can be improved and deterioration due to age can be retarded are accepted, then the consequences of these possibilities must be analyzed in relation to the planning of health care systems and to the planning of national health care programs. Thus, any attempt to describe the natural history of the health process must include the effects of interventions aimed at the promotion of health in the absence of disease. These effects must be defined so that quantitative criteria, which would serve as the basis for predictive medicine, can be established. Quantitative predictive medicine is necessary in order to evaluate the effectiveness of preventive measures. While it is widely recognized that the prevention of disease is one of the major goals of a health care delivery system, the methods presently used to evaluate alternative courses of action are notoriously limited. 相似文献
88.
The previously reported arrest of cell growth in the lateral geniculate nucleus (LGN) following unilateral lid suture during visual immaturity in cats, dogs and monkeys could be caused by deprivation of light or form vision, binocular interaction or a combination of these factors. The lens was surgically removed from one eye of 3 macaques during the first month of life. Quantitative histologic comparison between LGN laminae connected with the phakic and aphakic eye revealed reductions of cell sizes in the monocular and binocular LGN segments receiving input from the aphakic eye of a magnitude comparable to that obtained by the lid suture technique. Since the amount of light stimulating the retina through an aphakic pupil is not reduced, we conclude that light deprivation can be excluded as a cause for arrest of cell growth in the LGN. 相似文献
89.
Michael D. Winniford Stacey M. Johnson David R. Mauritson James S. Rellas Gregory A. Redish James T. Willerson L.David Hillis 《The American journal of cardiology》1982,50(4):913-918
This study was performed (1) to assess the efficacy and safety of verapamil in patients with variant angina, and (2) to compare verapamil and nifedipine in patients with this clinical syndrome. In 27 patients, placebo and verapamil were administered in a long-term, randomized, and double-blind study of 9 months' duration. In comparison to placebo, verapamil reduced the frequency of angina, nitroglycerin usage, transient episodes of electrocardiographic S-T segment deviation (as assessed by 2-channel Holter monitoring), and hospitalisations required for clinical instability. Subsequently, 23 patients were treated with nifedipine in a nonblind fashion for 2 months, and this agent exerted a beneficial effect similar to that of verapamil. Finally, gated equilibrium blood pool scintigraphy, performed in 10 patients at rest and during exercise during treatment with placebo, verapamil, and nifedipine, demonstrated that neither calcium antagonist caused a deterioration of left ventricular performance. Thus, (1) long-term oral verapamil and nifedipine are each superior to placebo and are of similar efficacy in patients with variant angina, and (2) neither agent adversely influences left ventricular performance in patients with relatively normal left ventricular function. 相似文献
90.