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81.
82.
In the present work, a hydroxyapatite anchored nitrogen-doped three-dimensional graphene (HAp-N3DG) skeletal network (foam) based nanostructured ceramic framework (CF) was developed through a polymer-assisted solvothermal route. Field emission scanning electron microscopy (FESEM) and transmission electron microscopy (TEM) studies reveal that the nano sized 0D HAp particles are anchored on the N3DG skeletal network with an average size of less than 50 nm. EDX and X-ray photoelectron spectroscopy (XPS) analysis confirmed the presence of Ca, P, O, N, and C. In addition, XPS analysis reveals the existence of N–C bonds in the prepared sample. The X-ray diffraction (XRD) patterns indicate the presence of hexagonal phase hydroxyapatite and the calculated average crystallite size was found to be 12 nm. The developed HAp-N3DG foam based nanostructured CF was found to have a mesoporous structure and the measured specific surface area (SSA) and the mean pore diameter were found to be 64.73 m2 g−1 and 23.6 nm, respectively. Electrochemical analysis shows that HAp anchored on nitrogen-doped 3D graphene foam based nanostructured CF has moderate electrochemical activity towards lithium ion charge/discharge. In addition, the prepared material showed adsorption activity values of 204.89 mg g−1 and 243.89 mg g−1 for the volatile organic compounds (VOCs) benzene and toluene, respectively. The present findings suggest that the newly developed HAp anchored nitrogen-doped 3DG (HAp-N3DG) skeletal network (foam) based nanostructured CF material can be used in energy devices and in the removal of volatile organic compounds. Moreover, the present study initiates a new kind of approach in energy device (lithium ion battery-LIB) research and in the removal of VOCs.

Hydroxyapatite anchored nitrogen-doped three-dimensional graphene (HAp-N3DG) skeletal network (foam) based nanostructured ceramic framework (CF) was developed through a polymer-assisted solvothermal route.  相似文献   
83.

Introduction

Thoracic trauma comprises 10–15 % of all traumas. The incidence and etiological pattern of chest trauma varies from region to region and is related to cultural and socio-political circumstances. This paper details our experience with thoracic trauma in a North Indian state.

Material & methods

All patients who were hospitalized for thoracic trauma from June 2010 to June 2012 in our hospital were enrolled. Data was collected prospectively and analysed. Factors analysed were age, gender, mode of injury, type of thoracic injury, associated injuries, management modalities, and outcome.

Results

The total number of patients was 250. The male to female ratio was about 10:1. The mean age of patients was 36.62 years. Road Traffic Accident (RTA) was the most common mode of chest injury. Motor-bike accident was the most common type of RTA. Majority of patients were managed with tube thoracostomy (183, 73.2 %). One hundred and eighty nine (75.6 %) patients were discharged after recovery. Ten (4.0 %) patients absconded. In all, 29 (11.6 %) patients died, while 22 (8.8 %) patients left the hospital against medical advice. A significant association between presence of associated injury and outcome was observed (p?<?0.001). We found mortality rate was significantly higher in chest injury associated with neurotrauma and abdominal visceral injury.

Conclusion

Chest trauma is a major health problem since it has high morbidity and mortality rate. The majority of patients with simple chest injuries can be managed by tube thoracostomy. According to our analysis; mortality predictors were: RTAs, blunt chest trauma, unstable hemodynamic status upon arrival, neurotrauma, abdominal visceral injury, flail chest, ventilator use, cardiac contusion and complications of therapy.  相似文献   
84.
Carcinosarcoma of esophagus contains both the carcinomatous and sarcomatous elements. These are rare polypoidal malignancies of esophagus. One such case is presented and available literature is reviewed.  相似文献   
85.
There is growing evidence that symptomatic femoroacetabular impingement leads to intra-articular damage and the development of early-onset osteoarthritis. Symptoms of femoroacetabular impingement often do not manifest until adulthood, but have been increasingly recognised in the paediatric and adolescent population. The surgical treatment of femoroacetabular impingement is aimed at restoring a more normal femoral head–neck offset in order to increase the clearance and prevent femoral abutment against the acetabular edge. Current methods include open and arthroscopic techniques. The latter has been combined with an open approach to gain access to the head–neck junction for osteochondroplasty. Proximal femoral and/or periacetabular osteotomies are used to treat femoroacetabular impingement associated with deformity secondary to childhood hip conditions, such as slipped capital femoral epiphysis and Legg–Calvé–Perthes disease. Some adolescents have severe degenerative joint disease at the time of presentation and may require arthroplasty or arthrodesis. The aim of this review is to identify the major trends and advancements in the management of femoroacetabular impingement in adolescents, including the outcome of studies of the surgical treatment modalities used.  相似文献   
86.
Our aim was to compare the use of a conventional rotary handpiece and a Piezosurgical unit for extraction of lower third molars. We studied 40 patients, who were allocated alternately to have the third molar removed with either the handpiece or the Piezosurgical unit. Pain, trismus, and oedema were evaluated at baseline and then postoperatively, together with paraesthesiae, on postoperative days 1, 3, 5, 7, and 15. Damage to surrounding tissue was checked on the same day whereas dry socket was evaluated from postoperative day 3 onwards. More patients complained of pain in the conventional group, they also required more analgesics, and they developed trismus more often than in the Piezosurgery group. There was also significantly more postoperative swelling in the conventional group. Patients were also evaluated using the subjective Postoperative Symptom Severity (PoSSe) scale. Our results suggest that apart from some inherent limitations with the Piezotome, it is a valuable alternative for extraction of third molars.  相似文献   
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Approximately 10%-20% of the cases of acute pancreatitis have acute necrotizing pancreatitis. The infection of pancreatic necrosis is typically associated with a prolonged course and poor prognosis. The multidisciplinary, minimally invasive “step-up” approach is the cornerstone of the management of infected pancreatic necrosis (IPN). Endosonography-guided transmural drainage and debridement is the preferred and minimally invasive technique for those with IPN. However, it is technically not feasible in patients with early pancreatic/peripancreatic fluid collections (PFC) (< 2-4 wk) where the wall has not formed; in PFC in paracolic gutters/pelvis; or in walled off pancreatic necrosis (WOPN) distant from the stomach/duodenum. Percutaneous drainage of these infected PFC or WOPN provides rapid infection control and patient stabilization. In a subset of patients where sepsis persists and necrosectomy is needed, the sinus drain tract between WOPN and skin-established after percutaneous drainage or surgical necrosectomy drain, can be used for percutaneous direct endoscopic necrosectomy (PDEN). There have been technical advances in PDEN over the last two decades. An esophageal fully covered self-expandable metal stent, like the lumen-apposing metal stent used in transmural direct endoscopic necrosectomy, keeps the drainage tract patent and allows easy and multiple passes of the flexible endoscope while performing PDEN. There are several advantages to the PDEN procedure. In expert hands, PDEN appears to be an effective, safe, and minimally invasive adjunct to the management of IPN and may particularly be considered when a conventional drain is in situ by virtue of previous percutaneous or surgical intervention. In this current review, we summarize the indications, techniques, advantages, and disadvantages of PDEN. In addition, we describe two cases of PDEN in distinct clinical situations, followed by a review of the most recent literature.  相似文献   
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