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61.
Rohan Ananda Rajan Keith J Hawkins James Metcalfe Charompolis Konstantoulakis Stanley Jones James Fernandes 《Journal of children's orthopaedics》2008,2(1):15-19
Purpose To demonstrate the effectiveness of intramedullary fixation of severely displaced proximal humeral physeal fractures in skeletally
immature children using the elastic stable intramedullary nail (ESIN).
Methods Retrospective recruitment of 14 patients aged 10–15-years old with severely displaced proximal humeral physeal fractures between
1999 and 2004 in a single regional specialist paediatric orthopaedic hospital. The fractures were graded using the Neer classification;
severe displacement constituted Neer II–IV or displacement >1 cm and angulation >45°. Patients were followed up and assessed
using the Disabilities of the Arm, Shoulder and Hand score (DASH) and the Neer Shoulder score. Radiographs were assessed for
deformity. Subjective satisfaction was assessed.
Results Fourteen patients with mean follow-up of 30 months (12–66 m) from surgery. All fractures were radiologically united at a median
time of eight weeks (7–10 weeks). At follow-up, Neer Shoulder mean score was 96.79 (range 83–100) and DASH mean score 2.26
(0–7.5). Subjectively 71% were very satisfied and 29% were satisfied.
Conclusions We commend stabilisation using ESIN in the management of the displaced proximal humeral physeal fracture in older children,
once reduction of the fracture has been achieved by either closed or open means. ESIN is safe and allows early return to pre-injury
function. 相似文献
62.
D R Sumner T M Turner R M Urban R M Leven M Hawkins E H Nichols J M McPherson J O Galante 《Journal of orthopaedic research》2001,19(1):85-94
The purposes of the present study were to determine if recombinant human transforming growth factor-beta-2 (rhTGF-beta2) enhances bone ingrowth into porous-coated implants and bone regeneration in gaps between the implant and surrounding host bone. The implants were placed bilaterally for four weeks in the proximal humeri of skeletally mature, adult male dogs in the presence of a 3-mm gap. In three treatment groups of animals, the test implant was treated with hydroxyapatite/tricalcium phosphate (HA/TCP) and rhTGF-beta2 in buffer at a dose per implant of 1.2 microg (n = 6), 12 microg (n = 7), or 120 microg (n = 7) and placed in the left humerus. In these same animals, an internal control implant treated only with HA/TCP and buffer was placed in the right humerus. In a non-TGF-beta treated external control group of animals (n = 7), one implant was treated with HA/TCP while the contralateral implant was not treated with the ceramic. In vitro analyses showed that approximately 15%, of the applied dose was released within 120 h with most of the release occurring in the first 24 h. The TGF-beta treated implants had significantly more bone ingrowth than the controls with the greatest effect in the 12 microg/implant group (a 2.2-fold increase over the paired internal control (P = 0.004) and a 4-fold increase over the external control (P < 0.001)). The TGF-beta treated implants had significantly more bone formation in the gap than the controls with the greatest effect in the 12 and 120 microg groups (1.8-fold increases over the paired internal controls (P = 0.003 and P = 0.012, respectively) and 2.8-fold increases over the external controls (P < 0.001 and P = 0.001, respectively)). Compared to the external controls, the internal control implants tended to have more bone ingrowth (1.9-fold increase, P = 0.066) and had significantly more bone formation in the gap (1.7-fold increase. P = 0.008). Thus, application of rhTGF-beta2 to a porous-coated implant-stimulated local bone ingrowth and gap healing in a weakly dose-dependent manner and stimulated bone regeneration in the 3-mm gap surrounding the contralateral control implant, a site remote from the local treatment with the growth factor. 相似文献
63.
Liu KJ Atten MJ Lichtor T Cho MJ Hawkins D Panizales E Busker J Stone J Donahue PE 《The American surgeon》2001,67(3):215-9; discussion 219-20
Serum amylase and lipase elevation has been observed in trauma patients and patients with traumatic intracranial bleeding. However, the causes of this elevation have not been clearly elucidated. A further question remains as to whether other intracranial events are associated with such enzyme elevation as well. We retrospectively reviewed 75 patients consecutively admitted to Cook County Hospital Neurosurgical Intensive Care Unit over a 3-month period for trauma, infection, tumor, or other space-occupying lesions with an unstable condition or neurological deficit. Eleven patients (15%) had elevated amylase and lipase levels. The patients were divided into two groups: Group I (n = 64) had normal and Group II (n = 11) had raised amylase and lipase levels [amylase 402 +/- 444 U/L with normal < or = 125 U/L and lipase 474 +/- 313 U/L with normal < or = 55 U/L]. All Group II patients suffered an intracranial event. Twenty-four Group I (38%) and 10 Group II (91%) patients required craniotomy (P < 0.01). No patients had clinical or radiographic evidence of pancreatitis. In summary, intracranial events are associated with serum amylase and lipase elevation probably through centrally activated pathways. Because of the lack of diagnostic value, routine pancreatic enzyme monitoring should not be performed in this patient population. 相似文献
64.
Zhang XJ Wu X Wolf SE Hawkins HK Chinkes DL Wolfe RR 《The Journal of surgical research》2007,142(1):90-96
BACKGROUND: Systemically administered insulin has been shown to accelerate wound healing. To minimize the hypoglycemic and hypokalemic effects of insulin, we investigated a new route of insulin administration by local injection into skin wounds. MATERIALS AND METHODS: Partial thickness skin donor site wounds were created on the backs of adult rabbits with a dermatome set at 0.015 inch. The wounds were covered by Aquaphor gauze (Smith and Nephew, Largo, FL), and OpSite membrane (Smith and Nephew, Hull, United Kingdom) and protected by rabbit jackets. Long-acting insulin-zinc suspension was selected for local injection. In study 1, insulin was injected into the wound at different doses, and the concentrations of blood glucose and wound insulin were measured to determine the proper dose and injection frequency. In study 2, wound healing days were compared between two groups (n = 7 each) receiving local injection of either insulin-zinc or zinc alone as control. Based on the results from study 1, a dose of 0.25 units of long-acting insulin-zinc suspension was injected into the wound every other day in the insulin group. RESULTS: After injection, 0.25 units of insulin decreased blood glucose concentration (minimum 60 mg/dL) during the first 3 h, which then returned to the preinjection level (80 mg/dL). One injection maintained wound insulin concentration above 50 muU/mL for more than 24 h. With local injection of 0.25 units insulin-zinc every other day, the wound healing time was 11.2 +/- 2.3 d, which was faster (P = 0.02) than 15.1 +/- 4.1 d in the control group. CONCLUSION: Local injection of long-acting insulin-zinc suspension accelerated skin wound healing without major systemic side effects, demonstrating its potential usefulness in burn treatment. 相似文献
65.
Anaesthetists rely upon a loss of resistance and flow of cerebrospinal fluid to indicate when a spinal needle has breached the dura. The loss of resistance is not always felt, with the danger that the needle may be advanced into neurological tissue. One hundred women undergoing elective caesarean section were recruited and spinal anaesthesia, using a 27-G Whitacre needle, was performed using an incremental advancement technique. After each advancement of the needle, and before removing the stylet, it was recorded whether the anaesthetist had perceived any sign that the dura had been breached, and then whether cerebrospinal fluid had been obtained. Six patients were not included in the study due to technical difficulties. In 27 of 94 patients (29%) there was no clear tactile sign that the dura had been breached when cerebrospinal fluid was obtained. This study demonstrates that loss of resistance is not always felt when a 27-G spinal needle breaches the dura in the pregnant woman. 相似文献
66.
67.
Hawkins GA Chang BL Zheng SL Isaacs SD Wiley KE Bleecker ER Walsh PC Meyers DA Xu J Isaacs WB 《The Prostate》2004,60(4):298-302
BACKGROUND: Telomerase activity is increased in most tumors. PinX1 has recently been identified as a critical component in regulating telomerase activity. The PinX1 gene is located within chromosomal region 8p22-23, a region associated with LOH and potentially linked to increased prostate cancer risk. METHODS: PINX1 was re-sequenced in 159 hereditary prostate cancer (HPC) probands. Four non-synonymous coding variants were genotyped in 159 HPC families. RESULTS: Thirty-nine polymorphisms were identified in the HPC screening panel. Ten coding polymorphisms were identified, seven (Gln50His, Leu91Met, Gln206His, Arg215Ile, Thr220Ala, Ser254Cys, and Glu414Ala) of which were non-synonymous. The most common variants Thr220Ala and Ser254Cys were not significantly over-transmitted from affected parent to affected offspring. CONCLUSIONS: Based on these results, we conclude that PINX1 is not a major factor for HPC risk. 相似文献
68.
The Harboe spectrophotometric assay is regarded as one of the safest and most reproducible methods for measuring plasma free hemoglobin (pfHb). However, there is still some ambiguity in the application of the assay when assessing the hemolytic performance of ventricular assist devices (VADs). The purpose of this study was to reexamine and compare values of pfHb obtained using different concentrations of plasma diluent (Na(2) CO(3) ) as cited by various studies such that a standard practice may be recommended for the application of the Harboe assay in the hemolytic evaluation of VADs, allowing reliable comparisons to be made between laboratories. As a means to examine the Harboe assay, a BioMedicus BPX-80 was tested using both whole blood and a washed suspension of red blood cells (RBCs). Results show that for whole blood, the pfHb may be underestimated by 13-23%, dependent upon the concentration of Na(2) CO(3) diluent solution. This trend was not observed for the washed suspension of RBCs. Furthermore, it is shown that the concentration of diluent influences the stability of a sample. The results of this study show that the problems associated with the incongruity of pfHb readings are a direct result of the precipitation of proteins from the plasma under alkaline conditions; as the molarity of the diluent controls pH, it becomes essential to use the appropriate concentration of Na(2) CO(3) diluent in order to avoid turbidity of the solution and the consequent misrepresentation of pfHb values. Such standardization is pertinent when measuring the very low levels of pfHb observed during the in vivo testing of modern ventricular assist devices. 相似文献
69.
Howard S. Barden Paul Markwardt Randy Payne Brent Hawkins Matt Frank Kenneth G. Faulkner 《Journal of clinical densitometry》2003,6(4):401-409
Modern bone densitometry systems using dual-energy X-ray absorptiometry (DXA) automatically analyze lumbar spine scans and provide clinically important information concerning spine bone mineral density (BMD) and fracture risk. Lumbar spine BMD accurately reflects skeletal health and fracture risk in most cases, but degenerative diseases associated with aging may lead to the formation of reactive bone (osteophytes) and other confounding conditions that elevate BMD without a concomitant increase in bone strength or decrease in fracture risk. Automated densitometry software known as computer-aided densitometry (CAD) (GE Medical Systems Lunar) assists the user in identifying scans with common acquisition and analysis irregularities known to influence BMD values. Visual examination of 231 female spine scans measured with DXA found abnormal conditions that could influence BMD results in 29% of scans. The sensitivity and specificity of several criteria for identifying scans with conditions that could influence BMD were determined. A good criterion for identifying scans with abnormal conditions was a T-score difference of greater than 0.9 or 1.0 between L1-L4 mean and individual vertebrae. Criteria for excluding affected vertebrae were determined. Exclusion of affected vertebrae resulted in a mean BMD decrease of nearly 0.6 SD (T-score) among affected scans. 相似文献
70.