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1.
OBJECTIVE: The use of Kirschner wire for the fixation of premaxilla is a well-known method in bilateral cleft lip surgery. We report a case in which the Kirschner wire of the premaxillary fixation had migrated intrasphenoidally. RESULTS AND CONCLUSIONS: The foreign body was accidentally discovered during a cephalometric analysis and was taken out surgically through an upper lip sulcus incision. Although the wire remained asymptomatic for 10 years, it constituted a potential danger for intracranial migration.  相似文献   
2.
The bond strength of porcelain fused to cast and wrought titanium surfaces was calculated from fracture loads in a 4-point bending test. Two different porcelain were applied (O'Hara and Duceratin). The surface of Ti-cast specimens was treated in two different ways to produce variations in the impurity level before porcelain veneering. Microhardness measurements as well as scanning electron microscopy with EDX analysis were conducted. The results showed no significant difference in bond strength between the two porcelains. Nor was any difference in bond capacity found between thoroughly blasted castings and wrought titanium. Significantly lower bond strengths were observed for lightly blasted specimens and for specimens treated with Gold bonding agent. Impurities in the surface region of the castings were found to be due to contact with the investment during solidification. This indicates that a thin surface layer (50-100 microns) of the casting should be removed before firing of the porcelain.  相似文献   
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In the present work, the mechanism of action of fosfomycin [(-)-(1R,2S)-(1,2-epoxypropyl)phosphonic acid] as an antibiotic agent is studied by "ab initio" quantum mechanical calculations and by 1H, 13C, and 31P NMR measurements. Attention is focused on the relative charge density and chemical shift of the C(2) atom of the epoxy ring, which seems to be closely related with the activity of this antibiotic. The theoretical results suggest that the sulfhydryl addition should be preceded by a necessary anchoring of the phosphonate moiety on a positive group of the receptor.  相似文献   
5.
The current standard for composite tissue preservation is static cold storage (SCS) and is limited to 6 h until irreversible muscle damage occurs. Extracorporeal perfusion (ECP) is a promising technique for prolonged preservation, however, functional results have been scarcely researched. This article assessed neuromuscular function and compared results to histological alterations to predict muscle damage after ECP. Forelimbs of twelve Dutch landrace pigs were amputated and preserved by 4 h SCS at 4–6 °C (n = 6) or 18 h mid-thermic ECP with University of Wisconsin solution (n = 6). Limbs were replanted and observed for 12 h. Sham surgery was performed on contralateral forelimbs (n = 12). Histology analysis scored four subgroups representing different alterations (higher score equals more damage). Muscle contraction after median nerve stimulation was comparable between ECP, SCS, and sham limbs (P = 0.193). Histology scores were higher in ECP limbs compared to SCS limbs (4.8 vs. 1.5, P = 0.013). This was mainly based on more oedema in these limbs. In-vivo muscle contraction was well preserved after 18 h ECP compared to short SCS, although histology seemed inferior in this group. Histology, therefore, did not correlate to muscle function at 12 h after replantation. This leads to the question whether histology or neuromuscular function is the best predictor for transplant success.  相似文献   
6.
Thermal analysis of aqueous solutions in which the solute does not crystallize immediately upon freezing was carried out to define the effects of experimental parameters on thermograms in the glass transition region. The intensity of enthalpy relaxations in the glass transition region is related to both the rate of cooling and the rate of heating through the glass transition region—slow cooling or slow heating increases the extent of structural relaxation in the glassy state and increases the intensity of the endotherm. Plots of the logarithm of heating rate versus l /Tg are linear, and activation enthalpies for structural relaxation are in the range of 210–350 kJ/mol. For polymeric solutes, both the activation enthalpies for structural relaxation and the heat capacity change accompanying the glass transition increase with increasing molecular weight of the solute. Molecular weight dependence of the observed midpoint of the glass transition agrees with the Fox–Flory relationship. Results are compared and contrasted with glass transitions in solid polymers and with the glass transition of hyperquenched water. Practical implications for characterization of formulations intended for freeze-drying are discussed.  相似文献   
7.
A new method of semi-frame mitral annuloplasty is presented. The advantages of this technique are discussed in the following case reports. Although only a few selective cases were available for application of this procedure, it appears suitable for correction of mitral insufficiency.  相似文献   
8.
E. L’Her 《Réanimation》2014,23(1):93-98
Sedation contributes to patient’s comfort and plays an essential role in the intensive care unit (ICU). Several clinical studies have reported the occasional use of volatile halogenated agents in the ICU; however, long-term use is possible in routine for the provision of a dedicated evaporator filter (AnaConDa? [ACD]). Because of their low cost and pharmacological characteristics with a rapid therapeutic effect, a high therapeutic index, a possible use regardless of age and underlying medical conditions, and a good knowledge of their adverse effects, halogenated agents could be considered like possible ideal anesthetic agents in the ICU. The objective of this technical note is to clarify the potential indications of ACD device and describe its operative principles and potential drawbacks.  相似文献   
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Recent changes in plasma transfusion practices for severe hemorrhage are largely related to the recognition of an early endogenous coagulopathy associated with traumatic injury. Observational and mostly retrospective data suggest improved survival rates with high-dose plasma therapy, up to a 1:1 ratio of fresh frozen plasma to packed red blood cells, but the quality of evidence is limited. Putting it into practice raises many issues (early identification of patients at risk of massive bleeding, extrapolation to non-trauma settings, alternative or adjunctive treatments, among others) that are discussed in this brief review.  相似文献   
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