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排序方式: 共有1319条查询结果,搜索用时 31 毫秒
1.
C. Edwin Polk DDS MSD David Buchanan PhD 《American journal of orthodontics and dentofacial orthopedics》2003,124(6):663-669
The cephalometric measurement known as Wits appraisal (AOBO) was studied to determine its importance in diagnosis, treatment, and prediction of treatment success. The Wits appraisal is used primarily to identify unreliable ANB values (those that do not accurately reflect the degree of horizontal jaw discrepancy, ie, those that differ greatly from the AOBO value). Therefore, differences between AOBO and ANB also were evaluated. Because neither measurement alone can assess jaw discrepancies with total accuracy, they were combined, plotted on a scattergram, and divided into equal zones to create a new index of horizontal skeletal discrepancies and treatment predictability. Pretreatment values correspond to treatment difficulty, and posttreatment values correspond to the effectiveness of treatment. Treatment time for each zone also was evaluated. We were able to draw several conclusions from this study. First, combining AOBO and ANB values results in a more accurate measurement of treatment difficulty. These combined values also can be used to predict both treatment time and the success of treatment for horizontal discrepancies. Second, the AOBO value predicts variations in treatment time at each ANB value. Finally, adding ANB and AOBO values and then dividing the total yields zones that represent statistically significant differences in treatment times and percentages of success. The zones also correlate with the difference between AOBO and ANB measurements. 相似文献
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L C Harlan B F Polk S Cooper T P Blaszkowski J Ignatius-Smith M Stromer H Mull 《American journal of preventive medicine》1986,2(5):256-261
The effects of labeling a person as hypertensive have important implications for hypertension screening. The Hypertension Detection and Follow-up Program (HDFP) provides an opportunity to examine the effects of labeling, treatment, and study assignment on a large group of hypertensives (n = 10,070). Their answers to questions regarding perceived health and general well-being asked at baseline and again one year later were analyzed. There was no significant change in the perceived health status of persons who were unaware of their hypertension at baseline and remained untreated at one year (labeling alone). The effect of labeling plus treatment was associated with a significant decrease in perceived health. The effect of antihypertensive drug therapy on perceived health status was examined in persons who were aware of their hypertension but not on treatment at baseline, and on treatment at one year. The stepped care group (SC) had a significant improvement in their perceived health and a significant decrease in the amount of time spent worrying about their health. The referred care group (RC) had no change. Program assignment effects were studied in individuals aware of their hypertension and on treatment both at baseline and one year later. Both the SC and RC groups had a significant improvement in their perceptions of their health status. The SC group had a significant decrease in time spent worrying about their health, while the RC group showed no change. These reassuring results fail to support the suggestion that labeling persons as hypertensive is necessarily followed by negative psychological consequences.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
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Perforated colorectal neoplasms: correlation of clinical, contrast enema, and CT examinations 总被引:2,自引:0,他引:2
Hulnick DH; Megibow AJ; Balthazar EJ; Gordon RB; Surapenini R; Bosniak MA 《Radiology》1987,164(3):611-615
Results of clinical, contrast enema (CE), and computed tomographic (CT) examinations in 39 patients with perforated colorectal neoplasms were retrospectively reviewed. Twenty patients were toxemic at initial presentation, but in only four patients was the diagnosis of perforated colorectal neoplasm initially suspected clinically. CE study was performed in 22 patients and enabled the diagnosis of perforated neoplasm in 11 cases, neoplasm alone in eight, and neither neoplasm nor perforation in three. CT was performed in 38 patients and enabled the diagnosis of perforated neoplasm in 36; pericolic phlegmon but no mass lesion was evident in two. In 16 patients, CT also demonstrated metastatic disease. Because of its reliability in establishing the diagnosis and staging the extent of the inflammatory and neoplastic disease, CT is indicated in cases of suspected or proved perforated colorectal neoplasm and in cases in which CE study findings are indeterminate or suggestive of perforated neoplasm. 相似文献
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Interest in cancer of the breast has begun to yield a concentrated sequence of specific information as to its basic nature, dietary influences, and its hormonal and genetic determinants. Clearly, the advent of improved early diagnosis has allowed the presentation to the clinician of a more favorable aspect of the tumor than has previously been seen, and has altered the overall clinical character of the disease. These advances open the possibilities of greatly expanded and enhanced treatment options, both for the informed physician and the inquiring patient. The rewards of early diagnosis include the possibilities of functional reconstruction, which may alter the potential patient attitude to such an extent that even earlier diagnosis will be achieved in years ahead. The complex issues of multimodality therapy and the honest and valid stratification of patients are the key issues in the further study of this challenging illness. 相似文献
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C Mavroudis S L Katzmark B L Ganzel L A Gray H C Polk 《The Annals of thoracic surgery》1988,46(6):615-618
Two hundred nine Duncan-Harley guinea pigs had intrathoracic inoculation with 10(8) Staphylococcus aureus, accompanied by blood and umbilical tape. One hundred fifty-two animals were excluded because of clinical recovery, early death, or complications related to intrathoracic polymethylmethacrylate (PMMA) bead placement. The remaining 57 animals had clinical signs of empyema thoracis and were the subjects of this study. Group I animals (N = 24) served as the controls and had no therapy. Group II animals (N = 14) were treated by intrathoracic placement of placebo PMMA beads. Group III animals (N = 19) were treated by intrathoracic placement of tobramycin sulfate-impregnated PMMA beads. There were no differences between the groups in pleural reaction or pneumonia scores. These findings demonstrate a similar host response to the established infection. Group III, however, had a higher sterilization rate than Groups I and II (p less than 0.05), a finding underlining the therapeutic effect of tobramycin-treated PMMA beads. We conclude that intrathoracic local antimicrobial therapy with slow-release tobramycin-impregnated PMMA beads may enhance empyema treatment by increasing the rate of local sterilization. More experiments are necessary to assess the efficacy of this potentially important therapeutic arm for the treatment of thoracic empyema. 相似文献
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