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61.
62.
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   
63.
64.
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   
65.

Objectives

To ascertain the prevalence, presentation, diagnosis, severity, and complications of HELLP syndrome.

Materials and Methods

This is a prospective observational study analyzing the conditions and the data of 24 cases of HELLP syndrome in a tertiary care hospital. The analysis was done for the demographic characteristics, presentation of these patients, complications associated, and the perinatal outcome.

Results

0.45 % of the patients admitted for delivery developed HELLP syndrome. Majority of the patients developed the condition in 30–36 weeks period of gestation, while five patients developed it in the postpartum period. The condition led to 12.5 % of maternal and 45.8 % of perinatal mortality.

Conclusion

HELLP syndrome is an important cause for maternal and perinatal morbidity and mortality.  相似文献   
66.
67.

Background

Most of the organs and tissues are preserved in formalin with its own set of disadvantages. Plastination is a unique method of permanently preserving tissue in a life like state. Plastination developed by western authorities is a labour and equipment intensive affair. Most common polymer used is S10, however this study uses easily available alternative polymers for plastination.

Method

Various polymers like Epoxy resins, Polypropylene resins, Orthocryl and silicone were used in plastinating the anatomical specimens. Specific methods were used for solid, hollow organs and brain specimens. The specimens were made to undergo stages of fixation, dehydration, impregnation and curing. The results were studied and interpreted under various parameters.

Results

The results were interpreted under various parameters like shrinkage, retention of colour, odour, pliability and retention of gross anatomy. The study concluded that Orthocryl and Epoxy resins retained maximum colour with minimal shrinkage while maximum discolouration was with polypropylene plastinates. Brain sections were best preserved in Orthocryl.

Conclusion

The study concluded that indigenous methods and materials can produce quality plastinates which can be an important adjunct to traditional methods of teaching however more studies need to be done for refinement.  相似文献   
68.

Background

Uterine artery embolisation (UAE) has evolved as a minimally invasive and effective alternative, treatment modality for women with symptomatic fibroids. We discuss our initial experience of UAE in the management of symptomatic fibroids.

Methods

Twenty five symptomatic patients of uterine fibroids were treated with UAE by selectively cannulating and injecting poly vinyl alcohol particles into the uterine arteries. Post treatment follow up was done at 2 and 6 months respectively.

Results

Pre-treatment, the sizes of fibroids were between 3.9 and 10.9 cm (mean 7.4) on ultrasonography. Of the total 25 patients, 49 uterine arteries were embolised with a technical success rate of 98%. Menorrhagia persisted in 7 patients, dysmenorrhea in 4 patients and pressure symptoms in 2 patients respectively in follow up study of six months which corresponds to a reduction in symptoms by 68% for menorrhagia, 71% for dysmenorhoea and 75% for those with pressure symptoms respectively. At 2 months follow-up post embolisation, the mean diameter of the fibroid was 4.03 cm (range 2–5.2 cm) and at 6 months 3.2 cm (range 1.3–4.1 cm), corresponding to size reduction of 45.5% and 57%, respectively. Follow up with ultrasonography at 2 and 6 months period showed successful fibroid reduction in 24 patients with corresponding reduction in the symptomatology. One patient remained symptomatic with increase in fibroid size and had to undergo hysterectomy.

Conclusion

Uterine artery embolisation can be considered as an alternative to hysterectomy in appropriately selected symptomatic patients of uterine fibroids.  相似文献   
69.
70.
Two chalcogenated ligands L1 and L2 containing anthracene core and amine functionality have been synthesized. Both the ligands have been characterized using 1H and 13C{1H} NMR techniques. The structure of L1 has also been corroborated by single crystal X-ray diffraction. Application of L1 and L2 as stabilizers for palladium nano-particles (NPs) has been explored and six different types of NPs 1–6 have been prepared by varying the quantity of stabilizer. The nano-particles have been characterized by PXRD, EDX, and HRTEM techniques. The size of NPs has been found to be in the range of ∼1–2 nm, 2–3 nm, 4–6 nm, 1–2 nm, 1–2 nm and 3–5 nm for 1–6 respectively. The catalytic activities of 1–6 have been explored for Suzuki–Miyaura coupling of phenyl boronic acid with various aryl halides. These NPs showed good catalytic activity for various aryl chlorides/bromides at low catalyst loading (5 mg). Among 1–6, the highest activity has been observed for NPs 1, probably due to their relatively small size and high uniformity in the dispersion. The recyclability of the NPs upto 5 catalytic cycles is a distinct advantage.

Monodispersed ultrasmall Pd nanoparticles synthesized utilizing bulky organochalcogen secondary amines as stabilizers and application in Suzuki coupling of aryl chlorides at low catalyst loading.  相似文献   
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