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31.
Abstract Surgical treatment of proximal humeral fractures still remains a challenge. This is primarily due to the fact that sufficient
implant fixation in humeral head fractures is often not achieved due to substantial bone tissue loss with increasing age.
In the last few years the locking plates and locking nails have been introduced into clinical practice with varying results.
The biomechanical studies have focused on locking plate osteosynthesis as well. The following paper focuses on bone quality,
biomechanical studies and biology of proper osteosynthesis and reviews the most recent literature. 相似文献
32.
33.
Alok Bhargava Matthew Jukes Damaris Ngorosho Charles Khilma Donald A P Bundy 《American journal of human biology》2005,17(3):280-292
This paper models the proximate determinants of school attendance and scores on cognitive and educational achievement tests and on school examinations of over 600 schoolchildren from the Control group of a randomized trial in Tanzania, where children in the Intervention group heavily infected with hookworm and schistosomiasis received treatment. The modeling approach used a random effects framework and incorporated the inter-relationships between school attendance and performance on various tests, controlling for children's health status, socioeconomic variables, grade level, and the educational infrastructure. The empirical results showed the importance of variables such as children's height and hemoglobin concentration for the scores, especially on educational achievement tests that are easy to implement in developing countries. Also, teacher experience and work assignments were significant predictors of the scores on educational achievement tests, and there was some evidence of multiplicative effects of children's heights and work assignments on the test scores. Lastly, some comparisons were made for changes in test scores of treated children in the Intervention group with the untreated children in the Control group. 相似文献
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35.
36.
Tarek A. Amer Tarek F. Elwakil Mahmoud S. Elbasiouny 《European journal of plastic surgery》2007,30(2):67-73
Haemangiomas are the most common tumours of infancy. They typically proliferate then involute with considerable variation
as regards to their rates of proliferation and involution. Haemangioma of the nasal tip is a lesion of special characteristics.
During proliferation, it expands, contracts and deviates the nasal cartilages. Particularly, it regresses slowly and frequently
involutes incompletely. That is why excision of the lesion is frequently suggested. The present study was conducted to evaluate
open rhinoplasty after initial non-excision treatment modalities namely, intra-lesional corticosteroid injections and laser
treatment, as a protocol of treatment for nasal tip haemangiomas. Twelve patients with nasal tip haemangiomas were included
in the present study. Patients of both sexes, of different ages, with deep and mixed haemangiomas were studied. Disfigurement
was the constant presenting symptom. Initial non-excision treatment reported different responses as denoted by the regression
of the lesions’ size. Haemangiomas constantly extended between the medial crura of the alar cartilages as noted by the constant
widening of the columella pre-operatively and the obvious separation of the nasal cartilages intra-operatively. This separation
was constantly found to require approximation by sutures. The results of the present study concluded that whenever an early
presentation with nasal tip haemangioma could be established, initial non-excision treatment followed by open rhinoplasty
could be a useful protocol of treatment. Within the limitations of the present study, this protocol could achieve an early,
safe and effective treatment for nasal tip haemangiomas with provisionally acceptable cosmetic outcomes so far. 相似文献
37.
This study investigates whether tissue recoil or patient intrinsic factors influence the final position of the nipple areola
complex (NAC) after reduction mammoplasty.
The age, pre-operative ptosis, BMI and weight of the tissue resected were recorded as patient intrinsic factors in 37 patients
undergoing reduction mammoplasty. The “spring-back” value was defined as the distance from the sternal notch to a nipple landmark
on the breast meridian with the patient sitting up, minus the same measurement repeated with the patient recumbent to eliminate
the pull of gravity on the breast. Spring back was measured pre-operatively for the nipple and nipple mark then post-operative
for the nipple. The difference in centimeters between the final post-operative distance from the sternal notch to the nipple
and the level intended by the pre-operative nipple mark was termed the “judgment error.” The final position of the post-operative
nipple and the judgment error was compared to the spring-back values and patient intrinsic factors.
Pre-operative ptosis was statistically related to increasing patient BMI and mass of tissue resected per breast. Pre-operative
spring-back values for the nipple increased with increasing ptosis, BMI and decreasing age. Spring-back values were greater
in the lower pole of the breast than in the upper pole. The final position of the nipple was higher than the pre-operative
mark in 65% of cases, lower in 8% and as marked in 27% of cases. The post-operative NAC was, on average, 0.6 cm higher than
planned pre-operatively. The post-operative distance from the sternal notch to the nipple increased with increasing pre-operative
ptosis, mass of breast tissue resected per breast and all three spring-back values. The difference between the level of the
pre-operative mark and the final nipple position showed a weak correlation with post-operative spring-back values.
The parameters of ptosis, BMI, weight of tissue resected per breast and pre-operative nipple spring back reflect body habitus
and breast size. Spring-back values vary between the upper and lower pole of the breast. The final NAC position was higher
than that intended at pre-operative marking in the majority of cases. The surgeon instinctively marks the nipple lower in
patients with greater pre-operative ptosis and in whom a larger resection is anticipated. Judgment error did not relate to
intrinsic factors nor to pre-operative spring-back values; hence, these parameters cannot be applied as predictive tools for
more accurate pre-operative marking of the nipple position. This study suggests that the pre-operative nipple mark should
be placed, with the patient sitting up, at least 23 cm from the sternal notch and 0.6 cm lower than the final position estimated
using the inframammary crease as a landmark.
An invited commentary on this paper is available at . 相似文献
38.
39.
Jamshid Shirani Jagat Narula William C. Eckelman Navneet Narula Vasken Dilsizian 《Journal of nuclear cardiology》2007,14(1):100-110
Conclusions Noninvasive imaging of neurohumoral upregulation in remodeled myocardium suggests that an imaging strategy can be developed
for predicting the rate of remodeling and likelihood of HF development. This should allow a more judicious use of neurohumoral
antagonists especially in subjects who do not have manifest HF.74 In others specific targeted imaging may allow timely selection of individualized treatment strategies and ensure optimization
of therapeutic intervention. Similar to ACE and AII receptors, multiple other targets in the hormonal cascades can identify
the likelihood of adverse and favorable remodeling.74 相似文献
40.
Researchers have demonstrated that certain types of pain coping are correlated with less pain severity and disability and that there are differences between Caucasians and African-American pain patients in their use of specific coping strategies. However, the extent to which racial group differences exist in the associations between pain coping strategies and pain severity, interference, and disability is unclear. Furthermore, the role of education in these associations is uncertain. We recruited a diverse community sample of individuals with chronic pain and their spouses to examine this issue (N = 105). Participants completed the Coping Strategies Questionnaire, Multidimensional Pain Inventory, and Sickness Impact Profile. Results showed that African-American participants reported significantly more pain severity, interference, and disability and reported using diverting attention and prayer and hoping pain-coping strategies significantly more often than Caucasian participants; however, only the racial group difference in prayer and hoping remained when controlling for education. We also examined whether race and education interacted with coping strategies in relating to pain and disability. Significant three-way interactions were found for physical and psychosocial disability, suggesting that educational level should be included in analyses exploring racial group differences. The results suggest the need for pain treatments that take into account the educational and cultural context of pain. PERSPECTIVE: This article demonstrates that demographic variables such as race and education should be considered together when evaluating the effectiveness of coping with pain. The findings have the potential to enhance research and clinical practice with diverse groups. 相似文献