Atrial Fibrillation ; surgery ; Catheter Ablation ; methods ; Humans

OBJECTIVEThis study aims to do the following: construct a three-dimensional finite element model of an labial inverted impacted maxillary central incisor and its supporting tissues, analyze stress distribution in the periodontal tissue when various tractions are exerted, and provide references for treating impacted maxillary central incisor.

METHODSA three-dimensional finite element model oflabial inverted impacted maxillary central incisor and its periodontal tissues was established using Mimics 10.01 and Ansys 14.0 software based on original cone beam computed tomography (CBCT) data. Various traction values (20, 30, 40, 50, 60, and 70 g) were exerted on the incisal margin in the direction perpendicular to the impacted tooth. Different Von Mises stress values were determined.

RESULTSStress distribution on the periodontal ligament increased with traction size. When 30 g traction was exerted on the labial inverted impacted maxillary central incisor, the Von Mises stress was 24 919.0 Pa, which was within the range of the optimum force and close to its maximum value.

CONCLUSIONThe optimum traction for early orthodontic treatment of labial inverted impacted maxillary central incisor is nearly 30 g.

Bone Neoplasms ; diagnosis ; pathology ; Breast Neoplasms ; diagnosis ; pathology ; Delayed Diagnosis ; Diagnostic Errors ; Female ; Frozen Sections ; Humans ; Intraoperative Period ; Retrospective Studies ; Thyroid Neoplasms ; diagnosis ; pathology

Adolescent ; Adult ; Aged ; Facial Nerve ; anatomy & histology ; pathology ; Female ; Humans ; Male ; Microsurgery ; Middle Aged ; Parotid Neoplasms ; surgery ; Young Adult

A strain of Cellulosimicrobium cellulans Ha8 was studied on its morphological, biological characteristics and its utilization of several kinds of benzoic compounds, the results showed this strain was Gram-positive, the long rod-shaped cells were changed into short rod-shape gradually. pH value from pH 6.0 to pH 9.0 and the temperature from 20 ℃ to 40 ℃ were good for its growth. It could not only hydrolyze protein and starch, use cellulose and pectin, decomposite chitin, liquify gelatin and fix nitrogen, but also use phenol, xylene, benzoic, cinnamic acids and diphenlamine as the sole carbon resource for its growth. It could tolerate 0 mmol/L~30 mmol/L, 0 mmol/L~8 mmol/L, 0 mmol/L~30 mmol/L, 0 mmol/L~15 mmol/L and 0 mmol/L ~ 40 mmol/L of benzoic acids, phenol, xylene, cinnamic acids and diphenlamine seperately, but could not use 2,4-dinitrophenol, o-Nitrophenol, 2-Methoxyphenol, aminobenzenesulfonic acid, catechol and o-Phenanthroline as its sole carbon resource.

Objective To investigate the possible damaging effect of infrasound on ultrastructure and permeability of rats′ blood retinal barrier (BRB). Methods Twenty mature male rats, averagely divided into 5 groups according to the exposure duration, were exposed to infrasound at a 16 Hz frequency and 130 dB sound pressure level in a pressure chamber for 2 hours per day. After exposed for 0, 1 day, 7, 14, and 21 days respectively, ultrastructural changes of rats′ BRB were observed through injection of lanthanum (La) nitrate solution, which was used as a tracer to demonstrate the breakdown of the BRB. Results With prolonging the duration of infrasound exposure, BRB structure lesion, chondriosome tumefaction, endoplasmic reticulum expandedness, membrane disc damage, retinal pigment epithelial cells distortion and putrescence, karyotheca expandedness, and La leakage on each level of retina aggravated gradually. Conclusion Infrasound may cause the breakdown of BRB, and the lesions aggravated with prolonged infrasound exposure time.

A sensitive LC-MS/MS method to determine cocaine and its major metabolite benzoylecgonine in guinea pig's hair has been established. About 20 mg of decontaminated hair sample was hydrolyzed with 0.1 mol·L-1 HCl at 50 ℃ overnight, in the presence of cocaine-d3 and benzoylecgonine-d8 used as internal standards, and then extracted with dichlormethane. The analysis was performed by liquid chromatography-tandem mass spectrometry (LC-MS/MS). Positive electrospray ionization (ESI+) and multiple reactions monitoring (MRM) mode were used. The limit of detection (LOD) for cocaine and benzoylecgonine was 1 pg·mg-1. The calibration curves of extracted standards were linear over the range from 5 pg·mg-1 to 250 pg·mg-1 (r2≥0.999 7). The method was validated and applied to the analysis of guinea pig's hair after a single dose administration of cocaine hydrochloride. Cocaine and benzoylecgonine were not only detected, but also quantified in guinea pigs hair.

ADAM Proteins ; blood ; immunology ; ADAMTS13 Protein ; Adult ; Female ; Humans ; Male ; Middle Aged ; Plasma Exchange ; Purpura, Thrombotic Thrombocytopenic ; blood ; pathology ; therapy