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991.
目的 探讨肠套叠空气灌肠整复的影响因素,提高肠套叠压力整复操作的安全性。方法 回顾性分析近5年来经我科诊治的217例小儿急性肠套叠的影像学、临床资料及未能整复的21例的手术病理改变。结果 整复失败21例手术所见:复杂型套叠15例、回结型套叠6例;术后病理改变:肠管坏死2例、器质性肠套叠1例、肠壁严重充血水肿18例。灌肠术中无一例并发穿孔。结论 整复失败与病程长、肠壁严重充血水肿及肠管坏死、患者年龄小、复杂型肠套叠、肠道畸形等有关。X线示套头大、分叶状,压力灌肠时显示“嵌顿征”、“绞窄征”及“弹簧套”等难以整复的重要征象。  相似文献   
992.
J. K. Wales 《Diabetologia》1982,23(3):240-245
Summary The effects of 3 months' diet therapy on glucose tolerance, plasma insulin response to oral glucose, fasting lipid levels and body weight were measured in 182 Type 2 (non-insulin-dependent) diabetic outpatients with fasting hyperglycaemia before treatment. Overall, there was a 25% improvement in glucose tolerance, a 58% increase in plasma insulin response during the glucose tolerance test, a 13.6% fall in fasting plasma triglyceride levels with no change in fasting cholesterol levels and a 5.1% fall in body weight. Of the 182 patients, 20% achieved normal glucose tolerance on diet alone for 3 months. These were mainly men of average age 63 years, who were 20% above their ideal body weight, and had milder glucose intolerance and higher residual insulin response to glucose before treatment than the 16% of patients who remained poorly controlled. These latter patients were mainly older women, 9% above their ideal body weight and with more marked glucose intolerance and less insulin response to glucose. These results demonstrate the practical limitations of this type of anti-diabetic therapy, particularly if normal glucose tolerance is a desired therapeutic aim.  相似文献   
993.
The objective of this study was to evaluate the cost-effectiveness of a state-of-the-art sexual-risk reduction intervention for high-risk men and women. The main intervention consisted of seven small-group sessions based on well-established principles of cognitive–behavioral therapy. This intervention was compared with a single-session video-based risk reduction intervention. The main outcome measure was the incremental cost–utility ratio, which equals the additional cost per additional quality-adjusted life year (QALY) saved by the cognitive–behavioral intervention, in comparison with the video intervention. A mathematical model of HIV transmission was used to translate reported sexual behavior changes into estimates of the number of HIV infections averted by the interventions, and associated savings in QALYs and averted HIV-related medical costs. For women, the incremental cost–utility ratio equaled $32,688 per QALY saved, which indicates that the cognitive–behavioral intervention was cost-effective compared to the video intervention. For men, the incremental cost–utility ratio was slightly negative, suggesting that the cognitive–behavioral intervention was highly cost-effective, or even cost-saving, compared to the video intervention. This analysis indicates that both brief and intensive sexual risk reduction interventions for high-risk populations can be cost-effective.  相似文献   
994.
995.
996.
Objective: The purpose of this retrospective study is to evaluate a clinical diagnostic sign for disc displacement without reduction (DDWR), the absence of additional condylar translation during opening compared with protrusion.

Method: Thirty-eight electronic axiographic and magnetic resonance imaging (MRI) examinations of the TMJ were analyzed in order to compare the opening/protrusion ratio of condylar translation between non-painful DDWR and non-DDWR.

Result: According to the Mann-Whitney U test, the opening/protrusion ratio in non-painful DDWR differs significantly from non-DDWR (p < 0.0001).

Discussion: Among non-painful DDWR, there is no additional condylar translation during opening in comparison with protrusion, and this is probably also the case for DDWR without limited opening, which is a subtype that has not been validated by the Diagnostic Criteria for Temporomandibular Disorders (DC/TMD). Comparative condylar palpation can analyze this sign, and therefore, further comparative investigations between MRI and clinical examination are needed to validate the corresponding clinical test.  相似文献   

997.
Objective: To verify the efficacy of treating dentin/dental hypersensitivity (DH) to Cold Ice Water Swish testing before and after subjects undergo the Immediate Complete Anterior Guidance Development (ICAGD) computer-guided occlusal adjustment.

Methods: One hundred chronically dysfunctional patients with known cold sensitivity swished ice water intraorally to elicit a DH response scored on a Visual Analog Scale (VAS). The subjects then underwent the ICAGD coronoplasty, which was followed by a second ice water swish scored with a second VAS. The pre to post ICAGD Disclusion Time values and VAS scores were statistically evaluated by the Wilcoxon Signed Rank for Paired Difference test. The subjects were divided into subgroups with DH sensitivities <4 and ≥4, and analyzed. Limitations were as follows: abfractions were not quantified, dysfunctional symptom resolution was not determined, each subject was their own control, one clinician administered all ice water tests, and protrusive excursions were not included.

Results: Disclusion Time reductions from ICAGD were significant (2.11–0.55 s. p = 0.0000). The DH score changes showed highly significant decreases from pre to post ICAGD (p < 0.0001).

Conclusions: A partial etiology for cold tooth sensitivity exists, resultant from prolonged occlusal surface excursive movement frictional contacts. This cold sensitivity can be lessened with measured, computer-guided occlusal adjustments.  相似文献   

998.
目的 探讨改良Twin-block治疗颞下颌关节盘可复性前移位前后关节盘形态和位置的变化.方法 将2015年7月~2016年6月就诊于深圳市第二人民医院口腔科,经临床及MRI检查诊断为单侧或双侧颞下颌关节盘可复性前移位,并接受改良Twin-block矫治器进行治疗者19例,共28侧关节纳入研究,治疗前后均拍摄MRI,测量治疗前后关节盘前后径、盘髁距离、盘髁角度并进行配对t检验,对治疗前后的关节盘形态进行Wilcoxon符号秩和检验,P<0.01为差异具有统计学意义.结果 19例患者28侧关节盘均存在可复性前移位,经过改良Twin-block治疗后,24侧关节盘位置恢复正常,4侧关节盘在闭口时仍处于前移位状态.治疗后关节盘前后径增加,盘髁距离、盘髁角度减小,差异均具有统计学意义(P<0.01).关节盘形态治疗前以V形最多(16侧),其次为双面平滑形(9侧);治疗后以双凹形(16侧)和双面平滑形(10侧)为主;治疗后关节盘形变程度减小,且差异有统计学意义(P<0.01).4侧关节盘复位失败者,治疗前盘髁距离及盘髁角度相对较大,关节盘形变相对较重.结论 改良Twin-block是治疗颞下颌关节盘可复性前移位的一种有效手段,可以使发生移位的关节盘前后径及位置恢复,使关节盘形变减小.但对于关节盘移位及形变程度较重者,其治疗效果可能不理想,还需进一步扩大样本量进行分层研究,并延长随访时间.  相似文献   
999.
1000.

Purpose

To investigate the optimal blending percentage of adaptive statistical iterative reconstruction (ASIR) in a reduced radiation dose while preserving a degree of image quality and texture that is similar to that of standard-dose computed tomography (CT).

Materials and Methods

The CT performance phantom was scanned with standard and dose reduction protocols including reduced mAs or kVp. Image quality parameters including noise, spatial, and low-contrast resolution, as well as image texture, were quantitatively evaluated after applying various blending percentages of ASIR. The optimal blending percentage of ASIR that preserved image quality and texture compared to standard dose CT was investigated in each radiation dose reduction protocol.

Results

As the percentage of ASIR increased, noise and spatial-resolution decreased, whereas low-contrast resolution increased. In the texture analysis, an increasing percentage of ASIR resulted in an increase of angular second moment, inverse difference moment, and correlation and in a decrease of contrast and entropy. The 20% and 40% dose reduction protocols with 20% and 40% ASIR blending, respectively, resulted in an optimal quality of images with preservation of the image texture.

Conclusion

Blending the 40% ASIR to the 40% reduced tube-current product can maximize radiation dose reduction and preserve adequate image quality and texture.  相似文献   
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