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31.
Purpose: Rib fractures are the most common skeletal thoracic injuries resulting from blunt chest trauma. Half of the rib fractures are not detected upon a precise physical evaluation and radiographs. Recently ultrasonography (USG) has been investigated to detect rib fractures. But based on literature the usefulness of USG varies widely. This study was conducted to investigate the role of USG in the detection of possible rib fractures in comparison with radiography. Methods: In this cross-sectional study, consecutive patients with minor blunt chest trauma and suspected rib fractures presenting in Imam Reza Hospital located in Mashhad-Iran, between April 2013 and October 2013 were assessed by USG and radiography. The radiography was performed in a posteroanterior (PA) chest projection and oblique rib view centered over the area of trauma. The time duration spent in taking USG and radiography were recorded. The prevalence and location of fractures revealed by USG and radiography were compared. Results: Sixty-one suspected patients were assessed. The male to female ratio was 2.4:1 (43 men and 18 women) with a mean ± SD age of (44.3 ± 19.7) years. There were totally 59 rib fractures in 38 (62.3%) patients based on radiography and USG, while 23 (37.7%) patients had no diagnostic evidence of rib lesions. USG revealed 58 rib fractures in 33 (54.1%) of 61 suspected patients and radiographs revealed 32 rib fractures in 20 (32.8%) of 61 patients. A total of 58 (98.3%) rib fractures were detected by USG, whereas oblique rib view and PA chest radiography showed 27 (45.8%) and 24 (40.7%) rib fractures, respectively. The average duration of USG was (12 ± 3) min (range 7e17 min), whereas the duration of radiography was (27 ± 6) min (range 15-37 min). The kappa coefficient showed a low level of agreement between both USG and PA chest radiography (kappa coefficient=0.28), and between USG and oblique rib view (kappa coefficient=0.32). Conclusion: USG discloses more fractures than radiography in most patients presenting with suspected rib fractures. Moreover USG requires significantly less time than radiography.  相似文献   
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The successful elimination of pathogenic cells and microorganisms by the humoral immune system relies on effective interactions between host immunoglobulins and Fcγ receptors on effector cells, in addition to the complement system. Essential Ig motifs that direct those interactions reside within the conserved IgG lower hinge/CH2 interface. We noted that a group of tumor-related and microbial proteases cleaved human IgG1s in that region, and the “nick” of just one of the heavy chains profoundly inhibited IgG1 effector functions. We focused on IgG1 monoclonal antibodies (mAbs) since IgG1 is the most abundant human subclass and demonstrates robust Fc-mediated effector functions. The loss of Fc-mediated cell killing activities was correlated with diminished binding to the Fcγ family of receptors, but a similar decrease in affinity was not observed toward the FcRn receptor that maintains IgG in circulation. Endogenous human IgG cleavage products of comparable size to mAbs with the single cleavage were detected by Western blot analysis in synovial fluid from patients with rheumatoid arthritis and in breast carcinoma extracts. Their detection is problematic under physiological conditions, since there is no loss of structure, and antigen-binding capability is unaffected. These findings suggest that within the hostile proteolytic microenvironments associated with many diseases, key effector functions of host IgGs, or therapeutic Abs, may be compromised.  相似文献   
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Objective: To illustrate mechanisms of spine fractures and the pattern of spinal injuries characterized by the major mechanisms in urban population of Iran. Methods: Data regarding spinal injuries including demographics, mechanism and level of spinal injury, abbreviated injury score, associated injuries and final fate of the patients were extracted from the Iranian national trauma registry database from 1999 to 2004. Results: A total of 619 patients with traumatic spine fractures were identified, of whom 68.5% were males. The peak frequency of these injuries occurred in the 21-40 year age-group. Accidental falls and road traffic crashes (RTCs) were the most common mechanisms of spinal fractures (47.2% and 44.1%, respectively). RTCs tended to occur in younger patients compared with accidental falls. The most common spinal region for spinal fracture was the lumbar spine (53.63%). Cervical spine fractures were significantly more common in RTCs, while lumbar spine fractures were more common in accidental falls (P〈0.001). A total of 171 (27.6%)patients had associated non-spinal injuries, of whom 127 had associated extremity injuries, and 55 had head injuries. Thirty-six (5.6%) patients had spinal cord injury (SCI).The injury severity score of the RTC group was significantly higher than that of accidental falls (P=-0.002). Fifteen (4%) patients died of traumatic injuries. The rate of death was significantly higher in RTCs compared with accidental falls (5.1% vs 2.1%, P=0.039). Conclusions: The patterns of spinal fractures are similar to those reported from developed countries. RTCs tend to affect the younger age population and are associated with a higher degree of associated injuries and mortality than accidental falls. Therefore preventive strategies should be based on reduction of the number and severity of RTCs.  相似文献   
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We present a case of gastric strangulation 6 months after laparoscopic adjustable gastric banding (LAGB). The 45-year-old woman presented to our emergency department with acute left upper quadrant abdominal pain. Initial upper gastrointestinal studies after emergency department presentation showed no flow through the gastric band and an unusual air/fluid level just above the band, not communicating with the proximal pouch. The patient underwent emergency diagnostic laparoscopy, during which strangulation of a portion of the gastric fundus was identified. During this laparoscopic procedure, the band was removed, and the strangulated portion of stomach was resected using a laparoscopic stapling device. The patient had an uneventful postoperative course and was discharged 6 days after surgery. We present this case as an example of a rare late acute complication resulting from LAGB, which should be recognized and treated surgically on an emergent basis.  相似文献   
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Background

Surgery training requires residents to focus on tasks while minimizing the effect of distractions. There is a need to develop training methodologies that can enable surgical residents to hone this ability.

Methods

Fourteen surgical residents were divided into 2 groups. They were trained to perform simulated tasks in a noiseless environment and subsequently performed these tasks in a distractive one. In a follow-up experiment, an experimental group was trained in noisy and distractive conditions and was compared with a control group trained in noiseless conditions.

Results

Residents who trained in noiseless environments possessed decreased surgical proficiency when performing the identical tasks in realistic environments (P < .05). Pretraining in a noisy environment improves surgical proficiency.

Conclusions

Noise and distractions can significantly impede performance of surgical residents, but this effect can be nullified by introduction of noise and distractions in the training environment.  相似文献   
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目的:评估先天性上睑下垂患者的弱视发病情况。方法:在本横断面研究中,包括1岁以上的先天性上睑下垂患者100例(114眼)。最佳矫正视力小于10/10或两眼之间至少相差2/10者定义为弱视。年幼患者不能进行斯内伦视力表检测者,观察其注视情况。不同弱视患者的类型:1)屈光参差性弱视:散光性屈光参差≥1.00D;远视性球镜屈光参差≥1.00D,近视性球镜屈光参差≥-3.00D(睫状肌麻痹);2)斜视性弱视,3)形觉剥夺性弱视(SDA)。观察弱视的总发病率及类型,并对单侧和双侧上睑下垂患者进行比较。结果:弱视的发生率在上睑下垂患者为39/114(34.2%),其具体原因:屈光参差性弱视占29.8%,SDA占10.5%,斜视性弱视4.3%,严重的上睑下垂患者弱视发病率更高,视轴遮盖者(OA)占76%,而视轴未遮盖者只占22%。在视轴遮盖的单侧眼睑下垂患者,散光屈光参差性弱视发生率更高,在双侧眼睑下垂至少1眼视轴遮盖者,球镜屈光参差性弱视发生率更高。无论单侧和双侧上睑下垂,如果有视轴遮盖,则SDA比较多见。结论:由于屈光参差性弱视比SDA发生率更高,关注导致的弱视所有原因对于预防儿童上睑下垂所致的弱视极其重要。  相似文献   
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