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1.
The purpose of this research was to verify the influence of Iodoform on antimicrobial potential of calcium hydroxide. S. aureus, E. faecalis, P. aeruginosa, B. subtilis, C. albicans were the biological indicators. The substances tested were: calcium hydroxide + saline; calcium hydroxide + Iodoform + saline; Iodoform + saline. For the agar diffusion test, 18 Petri plates with 20 ml of BHI agar were inoculated with the microbial suspensions. Fifty-four cavities were made and filled with the substances tested. The diameters of microbial inhibition were then measured. In direct exposure test, 162 #50 sterile absorbent paper points were immersed in the experimental suspensions for 5 min, and covered with the pastes. At intervals of 24, 48 and 72 hours, the paper points were immersed in 10 ml of Letheen Broth, followed by incubation at 37°°C for 48h. Microbial growth was evaluated by turbidity of the culture medium. A 0.1 ml inoculum obtained from the Letheen Broth was transferred to 7 ml of BHI, and incubated at 37°°C for 48h. Bacterial growth was again evaluated by turbidity of the culture medium. The calcium hydroxide associated with the saline or the iodoform plus saline showed antimicrobial effectiveness in both experimental methods. The iodoform paste presented antimicrobial ineffectiveness for the agar diffusion test on all biological microorganisms and for the direct exposure test on B. subtilis and on the mixture.  相似文献   
2.
Odontology - Endodontics has gained emphasis in the scientific community in recent years due to the increase in clinical and in animal models studies focused on endodontic medicine, which aims to...  相似文献   
3.
Objective:To determine the frequency of apical root resorption (ARR) due to orthodontic treatment using cone beam computed tomography (CBCT) in a sample of 1256 roots from 30 patients.Materials and Methods:All patients had Class I malocclusion with crowding. Of the 30 patients evaluated, 11 were boys and 19 were girls; their mean age was 13 years (11 to 16 years). Orthodontic treatment followed the nonextraction treatment. CBCT images were obtained before and after orthodontic treatment, and ARR was determined using Axial Guided Navigation of CBCT images.Results:All patients had ARR. No statistically significant association was found between resorption frequency, gender, and age. ARR was detected using CBCT in 46% of all roots that underwent orthodontic treatment.Conclusions:CBCT was effective for detecting in vivo even minimal degrees of ARR due to orthodontic treatment and allowed three-dimensional evaluation of dental roots and visualization of palatine roots of maxillary molars. The highest frequencies and the most significant ARR occurred in incisors and distal roots of first maxillary and mandibular molars.  相似文献   
4.

Introduction

Radiographic images may lead to misinterpretations of lesions of endodontic and nonendodontic origin. This report describes a case of a 10-year follow-up of a calcifying odontogenic cyst (COC) in the periapical region of a vital maxillary central incisor in a 9-year-old boy.

Methods

The patient revealed a history of a swelling in the periapical area of tooth #9. The patient denied any dental trauma or history of pain. Clinical examination revealed no mobility, but there was discrete discomfort when horizontal pressure was applied. Pulp vitality was present in all maxillary anterior teeth. Radiographs revealed an oval radiolucent lesion in the periapical region of maxillary central incisor. The therapeutic option was enucleation of the periapical lesion and histologic examination of the specimen. Microscopic findings suggested the diagnosis of a COC.

Results

At a follow-up visit 10 years after surgery, panoramic and periapical radiographs showed new bone formation; the patient did not have any pain, and pulp vitality was maintained in all teeth in this area.

Conclusions

A COC should be part of the differential diagnosis of other jaw lesions, such as apical periodontitis. The definitive diagnosis of a COC can only be made after microscopic evaluation of the specimen. The follow-up is a helpful reference because it confirms the survival of pulp tissue and no recurrence of the COC.  相似文献   
5.
Despite the increasing life expectancy, an individual’s later years tends to be accompanied by a decrease in the quality of life. Though biological changes that occur through the natural process of aging cannot be controlled, the risk factors associated with lifestyle can. Thus, the main goal of this systematic review was to evaluate how nutrition can modulate aging. For this purpose, thirty-six studies were selected on (i) the efficiency of nutrition’s effect on aging, (ii) the evaluation of biomarkers that promote healthy aging, and (iii) how to increase longevity through nutrition, and their quality was assessed. The results showed that choosing low carbohydrate diets or diets rich in vegetables, fruits, nuts, cereals, fish, and unsaturated fats, containing antioxidants, potassium, and omega-3 decreased cardiovascular diseases and obesity risk, protected the brain from aging, reduced the risk of telomere shortening, and promoted an overall healthier life. With this study, the conclusion is that since the biological processes of aging cannot be controlled, changing one’s nutritional patterns is crucial to prevent the emergence and development of diseases, boost longevity, and, mostly, to enhance one’s quality of life and promote healthy aging.  相似文献   
6.
Classification of breast tissue by electrical impedance spectroscopy   总被引:4,自引:0,他引:4  
Electrical impedance spectroscopy is a minimally invasive technique that has clear advantages for living tissue characterisation owing to its low cost and ease of use. The present paper describes how this technique can be applied to breast tissue classification and breast cancer detection. Statistical analysis is used to derive a set of rules based on features extracted from the graphical representation of electrical impedance spectra. These rules are used hierarchically to discriminate several classes of breast tissue. Results of statistical classification obtained from a data set of 106 cases representing six classes of excised breast tissue show an overall classification efficiency of ∼92% with carcinoma discrimination >86%.  相似文献   
7.
Determination of chlorine ions of pesticides was performed after dechlorination reaction using a palladium/magnesium system. Chlorine ions were quantified by potentiometry with ion-specific electrode. Rates of dechlorination of 100 μg of DDT as a function of reaction time and percent (wt/wt) of palladium deposited on the magnesium particles were determined. The best reaction conditions to DDT dechlorination were achieved with an acetone/water (1:1) solution and DDT reaction with a 0.27% (wt/wt) palladium/magnesium bimetallic system at room temperature for 10 min. The detection limit was of 0.24 μg/mL. This low cost method showed an efficiency of 92% in determining chlorine ions derived from DDT, it is fast, requiring no specialized laboratory equipment.  相似文献   
8.
The purine ribonucleoside adenosine (Ado) has been recognized for its regulatory functions in situations of cellular stress like ischemia, hypoxia and inflammation. The importance of extracellular Ado as a modulator in the immune system is a theme of great appreciation and the focus of recent increasing interest in the field of gastrointestinal inflammation. In this review, the different aspects of Ado signaling during inflammatory responses in the gut are discussed, considering the contribution of the four known Ado receptors (ARs; A(1), A(2A), A(2B), and A(3)), their mechanisms and expression patterns. Activation of these receptors in epithelial cells as well as in immune cells recruited to the inflamed intestinal mucosa determines the overall effect, ranging from a protective, anti-inflammatory modulation to a strong pro-inflammatory induction. Here we present the current advances in agonists and antagonists development and their potential therapeutic application studied in animal models of intestinal inflammation. In addition, alternative complementary approaches to manipulate such a complex signaling system are discussed, for example, the use of AR allosteric modulators or interference with Ado metabolism. Special features of the gut environment are taken into account: the contribution of diet components; the involvement of Ado in intestinal infections; the interactions with the gut microbiome, particularly, the recent exciting finding that an intestinal bacterium can directly produce extracellular Ado in response to host defense mechanisms in an inflammation scenario. Understanding each component of this dynamic system will broaden the possibilities for applying Ado signaling as a therapeutic target in gut inflammation.  相似文献   
9.
The absorption of gabapentin (Neurontin) is dose-dependent and variable between patients. Rapid clearance of the drug necessitates dosing three or more times per day to maintain therapeutic levels. These deficiencies appear to result from the low capacity, limited intestinal distribution, and variable expression of the solute transporter responsible for gabapentin absorption. Saturation of this transporter at doses used clinically leads to unpredictable drug exposure and potentially ineffective therapy in some patients. XP13512 [(+/-)-1-([(alpha-isobutanoyloxyethoxy)carbonyl]aminomethyl)-1-cyclohexane acetic acid] is a novel prodrug of gabapentin designed to be absorbed by high-capacity nutrient transporters located throughout the intestine. XP13512 was efficiently absorbed and rapidly converted to gabapentin after oral dosing in rats and monkeys. Exposure to gabapentin was proportional to prodrug dose, whereas exposure to intact XP13512 was low. In rats, >95% of an oral dose of (14)C-XP13512 was excreted in urine in 24 h as gabapentin. In monkeys, oral bioavailability of gabapentin from XP13512 capsules was 84.2% compared with 25.4% after a similar oral Neurontin dose. Compared with intracolonic gabapentin, intracolonic XP13512 gave a 17-fold higher gabapentin exposure in rats and 34-fold higher in monkeys. XP13512 may therefore be incorporated into a sustained release formulation to provide extended gabapentin exposure. XP13512 demonstrated improved gabapentin bioavailability, increased dose proportionality, and enhanced colonic absorption. In clinical use, XP13512 may improve the treatment of neuropathic pain, epilepsy, and numerous other conditions by increasing efficacy, reducing interpatient variability, and decreasing frequency of dosing.  相似文献   
10.

Objective

The aim of this study was to compare periapical radiographs with cone beam CT (CBCT) imaging in detecting and localizing alveolar bone loss by comparing linear measurements of the height, depth and width of the defects and identifying combined bone defects in tomographic images.

Methods

The images were selected from a secondary database containing images of patients referred for periodontal evaluation. The sample consisted of 51 sites showing both horizontal and vertical bone loss, assessed by 3 trained examiners.

Results

The results showed that there were no statistically significant differences between the imaging methods in terms of identification of the pattern of bone loss. However, there were differences between the two methods when the distance between the cemento-enamel junction (CEJ) and the alveolar crest (AC) was measured. When the distance between the CEJ and the deepest point and width of the defect were measured, the methods showed no statistically significant difference. In this study, 30.8% of the 39 teeth evaluated had combined bone defects.

Conclusions

The two methods differ when detecting the height of the alveolar bone crest but present similar views of the depth and width of bone defects. CBCT was the only method that allowed for an analysis of the buccal and lingual/palatal surfaces and an improved visualization of the morphology of the defect.  相似文献   
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