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Maxillofacial injuries are usually not life-threatening and do not get priority over other associated injuries. However, some maxillofacial injuries with active oral or nasal bleeding need immediate management due to threatened airway and blood loss. In the case of major active vascular bleeding, measures such as local pressure, anterior nasal packing, posterior nasal packing, and balloon tamponade are ineffective. In these cases, angiography and transcatheter arterial embolisation (TAE) are used to treat life-threatening haemorrhage caused by maxillofacial trauma. We analysed the medical records of 39 patients with severe maxillofacial trauma and life-threatening haemorrhage that was a result of intractable oral or nasal bleeding. These patients were considered for TAE from January 2010 to December 2019. A total of 1668 patients was admitted, out of which 39 (2.3%) had severe maxillofacial injuries with life-threatening oral or nasal bleeding and underwent TAE. Out of a total of 39 patients, 38 were male and one female. Ages ranged from 16 to 65 years. Road traffic injury was the most common cause of injury (79.5%), Lefort I and II were the most common facial fractures, and traumatic brain injury was the most common associated injury. Embolisation and bleeding control were done successfully in all 39 patients with no procedure-related complications. A total of 17 deaths during the study period were due to severe traumatic brain injuries or haemorrhagic shock.  相似文献   
23.
Sol–gel-synthesized Co–Cu–Zn ferrite nanoparticles diluted with Dy3+ ions were investigated in terms of their structural, morphological, elastic, magnetic and dielectric properties. X-ray diffraction patterns showed the formation of a single-phase cubic spinel structure. As the concentration of Dy3+ ions was increased, the lattice length gradually increased from 8.340 to 8.545 Å, obeying Vegard''s law. The Williamson–Hall (W–H) method was employed to observe the change in the lattice strain. Crystallite size obtained from W–H plots followed a pattern similar to that observed using the Scherrer equation. The cation distribution suggested a strong preference of Dy3+ ions for the octahedral B site while Cu2+ and Fe3+ ions were distributed over both A and B sites. The microstructures of the samples were visualized using transmission electron microscopy. Mechanical properties such as stiffness constant, longitudinal and transverse wave velocities, Young''s modulus, bulk modulus, rigidity modulus, Poisson''s ratio and Debye temperature were investigated by acquiring infrared spectra recorded in the range of 300 to 800 cm−1. Replacement of Fe3+ ions with the strongly magnetic Dy3+ ions increased the saturation magnetization and coercivity. Dielectric constant increased with Dy3+ substitution but decreased with applied frequency.

Improvement in various properties of Co–Cu–Zn ferrite upon Dy substitution.  相似文献   
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Although highly active antiretroviral therapy (HAART) has resulted in remarkable decline in the morbidity and mortality in AIDS patients, controlling HIV infections still remain a global health priority. HIV access to the CNS serves as the natural viral preserve because most antiretroviral (ARV) drugs possess inadequate or zero delivery across the brain barriers. Thus, development of target‐specific, effective, safe, and controllable drug‐delivery approach is an important health priority for global elimination of AIDS progression. Emergence of nanotechnology in medicine has shown exciting prospect for development of novel drug delivery systems to administer the desired therapeutic levels of ARV drugs in the CNS. Neuron‐resuscitating and/or antidependence agents may also be delivered in the brain through nanocarriers to countercheck the rate of neuronal degradation during HIV infection. Several nanovehicles such as liposomes, dendrimers, polymeric nanoparticles, micelles, and solid lipid nanoparticles have been intensively explored. Recently, magnetic nanoparticles and monocytes/macrophages have also been used as carrier to improve the delivery of nanoformulated ARV drugs across the blood–brain barrier. Nevertheless, more rigorous research homework has to be elucidated to sort out the shortcomings that affect the target specificity, delivery, release, and/or bioavailability of desired amount of drugs for treatment of neuroAIDS. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   
26.
Objective : To evaluate serial head circumference (HC) measurements and neurodevelopmental (ND) screening before and after surgical revision for craniosynostosis. Design : Retrospective assessment. Setting : Tertiary institutional. Patients, Participants : All children treated with single-stage frontal-orbital advancement or total calvarial expansion for single-suture (SS) or multiple-suture (MS) craniosynostosis over a 7-year period. Main Outcome Measures : Changes in ND and HC were measured over postoperative visits after the primary surgery. More importantly, ND and HC changes were measured prerevision and postrevision. Results : Of 183 patients undergoing primary surgery, complete records and adequate follow-up were available for 112 patients. The overall revision rate was 21% (n = 23). Postrevision follow-up was adequate for 18 of the 23 revisions. After primary surgery, but prior to revision, children demonstrated a larger decline in HC (z-score, median = -1) along with higher ND findings (median = 2) from one postoperative visit to the next than those who did not go on revision (HC z-score median = 0, ND median = 0). After revision, patients demonstrated a significant improvement in ND screening findings (median ΔND findings = -2) compared with prerevision ND (p < .001). Head circumference also significantly increased by a z-score of +1 postrevision (p = .001). Conclusions : Patients chosen for revision surgery display not only a larger decline in HC but also more ND findings prior to revision. Furthermore, surgical revision has a significant association with both improved ND screening and HC.  相似文献   
27.
Diffuse large B‐cell lymphoma (DLBCL) occasionally presents with circulating malignant cells. The clinical characteristics and long‐term outcomes of these patients have not been described. Twenty‐nine newly diagnosed DLBCL presenting in leukaemic phase were identified between 1996 and 2010, at two institutions. Median age was 48 years, and patients presented with leucocytosis, high lactate dehydrogenase levels, B symptoms, and high International Prognostic Index score. Extra nodal site involvement was observed in all patients and affected the bone marrow (100%), spleen (62%), pleura/lung (41%), liver (21%), bone (17%), bowels (7%) and cerebrospinal fluid (14%). Blood lymphomatous cells co‐expressed CD19, CD20, CD22, CD38, CD45, HLA‐DR and FMC7 in >90%, and kappa or lambda light chain restriction in >50%. Ninety per cent received rituximab and anthracycline‐based chemotherapy. Overall, remission was complete in 54% and partial in 31%; 15% had resistant disease. Median follow‐up was 47 months; 13 (45%) patients remain alive in complete remission. Median progression‐free and overall survivals were 11·5 and 46·7 months, respectively. In summary, patients with DLBCL in leukaemic phase present with high tumour burden and frequent involvement of extra nodal sites. In this uncommon DLBCL subgroup, anthracycline‐based regimens with rituximab are associated with early morbidity and mortality, but yield approximately 50% 4‐year survival.  相似文献   
28.
Acute coronary artery obstruction at the time of device implantation is a recognized, albeit rare, complication of TAVI and is most frequently managed by emergency percutaneous intervention. This complication usually manifests with circulatory collapse due to compromising left ventricular ischemia and is most often observed immediately following valve deployment in the catheter laboratory or in theater. Immediate circulatory support is often necessary. We describe the first report of delayed left main stem obstruction 3.5 hours after successful deployment of a 26 mm Edwards SAPIEN XT valve via transfemoral implantation, with sudden development of circulatory collapse on the ward. Circulatory support was rapidly and effectively instituted with an automated non-invasive cardiac massage device, AutoPulse, that delivers continuous chest compressions. Successful emergency percutaneous intervention was then undertaken to the left main stem to displace a calcified nodule during automated external cardiac massage with the AutoPulse.  相似文献   
29.
The direct oxidative cleavage of activated alkynes via hydroamination has been described using organic photocatalyst under visible-light irradiation at room temperature. In this reaction, the single electron oxidation of an in situ formed enamine followed by radical coupling with an oxidant finally delivers the oxamate. The key features of this photocatalytic reaction are the mild reaction conditions, metal-free organic dye as a photocatalyst, and TBHP playing a dual role as “O” source and for the regeneration of the photocatalyst.

The direct oxidative cleavage of activated alkynes via hydroamination has been described using organic photocatalyst under visible-light irradiation at room temperature.  相似文献   
30.

Objective:

To discuss the clinical presentation, diagnosis and management of osteomas involving the craniomaxillofacial region.

Materials and Methods:

This study was conducted from June 2004 to March 2012 at our institute. A total of 12 cases between the ages of 10 and 50 years were managed with surgical excision and reconstruction. The criteria used to diagnose osteoma included radiographic and clinical features and histological confirmation of the specimen. The total follow-up period ranged from 6 to 24 months.

Results:

Out of 12 osteomas, 10 were peripheral and 2 were centrally located. Mandible involvement was seen in six patients, four involved the orbit, one the frontal bone and one the frontal bone with the skull base. All patients undergoing excision and reconstruction had a favourable aesthetic and functional outcome. There were no recurrences and no post-operative complications.

Conclusion:

Osteomas affect all age groups with no sex predilection and are usually clinically asymptomatic till they become large in size. Surgical excision and appropriate reconstruction is the mainstay of management. Surgery is indicated when lesion is symptomatic or actively growing and the surgical approach for exposure of the lesion should be case specific.KEY WORDS: Craniofacial, osteoma, reconstruction  相似文献   
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