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691.

Objective

The purpose of this study was to determine whether healthy adult volunteers report symptoms following exposure to low-speed frontal crashes at low velocities.

Methods

Nineteen medically screened, healthy, informed, and willing volunteers (17 men, 2 women; mean age, 37 years) were exposed to low-speed frontal crashes. All volunteers were seated in the rear seat position of the bullet vehicle. Closing velocities ranged from 4.1 to 8.3 mph (mean, 6.7 mph). For the bullet vehicle, the delta V ranged from 1.4 to 3.9 mph with a mean of 2.8 mph.

Results

Eighty-eight percent of volunteers attributed symptoms of discomfort to their crash exposure. All reported symptoms were transient, and none required medical treatment. The mean duration was 1 day.

Conclusions

Even at relatively low speeds, there is no lower threshold below which it can be reasonably assumed that healthy and prepared volunteer rear seat passengers will not sustain some level of minor injury in a frontal collision. Although the reported mean delta V for injured persons in real-world frontal crashes has been reported to be as high as 8.1 mph, this does not offer any insight into the minimum threshold for such injuries among all at-risk vehicle occupants.  相似文献   
692.

Background:

Lateral closed wedge (LCW) osteotomy is a commonly accepted method for the correction of the cubitus varus deformity. The fixation of osteotomy is required to prevent loss of correction achieved. The fixation of the osteotomy by the two screw and figure of eight wire is not stable enough to maintain the correction achieved during surgery. In this prospective study we supplemented the fixation by Kirschner''s (K-) wires for stable fixation and evaluated the results.

Materials and Methods:

Twenty-one cases of the cubitus varus deformity following supracondylar fractures of the humerus were operated by LCW osteotomy during February 2001 to June 2006. The mean age of the patients at the time of corrective surgery was 8.5 years (range 6.6-14 years). The osteotomy was fixed by two screws with figure of eight tension band wire between them and the fixation was supplemented by passing two to three K-wires from the lateral condyle engaging the proximal medial cortex through the osteotomy site.

Result:

The mean follow-up period was 2.5 years (range seven months to 3.4 years). The results were assessed as per Morrey criteria. Eighteen cases showed excellent results and three cases showed good results. Two cases had superficial pin tract infection.

Conclusion:

The additional fixation by K wires controls rotational forces effectively besides angulation and translation forces and maintains the correction achieved peroperatively.  相似文献   
693.
694.
中药材X-射线衍射图谱研究   总被引:66,自引:0,他引:66  
为探讨中药材道地性的客观规律,以期建立相应的评估指标系统,本文选择常用中药材茜草类、贝母类、山药类三组样品,应用X-射线粉末衍射法进行图谱分析,获得了可用于标识中药材的衍射图形几何拓扑规律与图谱特征标记峰,由此观察到:不同产地茜草样品的相似性及其与欧茜草的差别;同属不同种贝母样品的相似性与差异;不同产地山药样品的相似性及与伪品的区别。本文结果预示着这一方法在揭示中药材道地性客观规律方面的广阔应用前景。  相似文献   
695.
696.

Objective

To characterize patterns in whole-person health of public health nurses (PHNs).

Design and Sample

Survey of a convenience sample of PHNs (n = 132) in 2022. PHNs self-identified as female (96.2%), white (86.4%), between the ages 25–44 (54.5%) and 45–64 (40.2%), had bachelor's degrees (65.9%) and incomes of $50-75,000 (30.3%) and $75-100,000/year (29.5%).

Measurements

Simplified Omaha System Terms (SOST) within the MyStrengths+MyHealth assessment of whole-person health (strengths, challenges, and needs) across Environmental, Psychosocial, Physiological, and Health-related Behaviors domains.

Results

PHNs had more strengths than challenges; and more challenges than needs. Four patterns were discovered: (1) inverse relationship between strengths and challenges/needs; (2) Many strengths; (3) High needs in Income; (4) Fewest strengths in Sleeping, Emotions, Nutrition, and Exercise. PHNs with Income as a strength (n = 79) had more strengths (t = 5.570, p < .001); fewer challenges (t = -5.270, p < .001) and needs (t = -3.659, p < .001) compared to others (n = 53).

Conclusions

PHNs had many strengths compared to previous research with other samples, despite concerning patterns of challenges and needs. Most PHN whole-person health patterns aligned with previous literature. Further research is needed to validate and extend these findings toward improving PHN health.  相似文献   
697.
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