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1.
This case report demonstrates how extracting a maxillary deciduous canine affects the eruption path of a labially displaced ectopically erupting permanent canine. A long-term follow-up is presented, and the biologic mechanisms are discussed.  相似文献   
2.
Statistical analysis of 550 isolated maxillo-facial fractures is presented. Data obtained illustrated the important number of maxillo-facial fractures in Sao Paulo, the automobilistics accidents were responsible for most maxillo-facial trauma, the jaw and the malar were more predominant than the others structures and the conservative treatment was the most used one.  相似文献   
3.
Purpose  To present a case of brainstem anaesthesia as a complication of peribulbar anaesthesia. Clinical features  A 75-yr-old woman received peribulbar anaesthesia for cataract surgery. A few seconds after the block was performed, she had a respiratory arrest, became unconscious, and developed hypertension and tachycardia followed by hypotension and bradycardia. Ventilatory and haemodynamic support were performed before the patient regained adequate spontaneous breathing and normal heart rate and blood pressure. Conclusion  Peribulbar anaesthesia generally cames a low risk of serious complications. However, respiratory arrest and brainstem anaesthesia may occur as complications of peribulbar blocks.
Résumé Objectif  Présenter un cas d’anesthésie du tronc cérébral compliquant une anesthésie péribulbaire. éléments cliniques  Un bloc péribulbaire était réalisé chez une femine de 75 ans pour l’extraction d’une cataracte. Quelques secondes après l’injection, la patiente cessait de respirer et perdait conscience. Elle devenait hypertendue et tachycarde puts hypotendue et bradycarde. La ventilation et la circulation devaient être supportées jusqu’au retour spontané à la normale. Conclusion  En général, l’anesthésie péribulbare comporte un faible risque de complications sérieuses. Un arrêt respiratoire par anesthésie du tronc cérébral est toujours possible.
  相似文献   
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The interaction of angiotensin with its receptor has been studied on the basis of the tachyphylaxis shown by the rat uterus towards angiotensin II when pH and Ca2+ concentration are below physiological levels. 14C-Angiotensin binding and 45Ca2+-uptake investigations suggest tachyphylaxis to be due to increased binding at low pH and Ca2+ concentration. Studies with alkylating (affinity labeled) angiotensin derivatives containing the N-mustard chlorambucil suggest a "Charnière type" inhibition at the Ca-binding site of receptor and an irreversible inhibition at an anionic site. Angiotensin inhibitors containing chlorambucil do not alkylate tissue but are competitive inhibitors suggesting that the aromatic side chain in angiotensin may induce conformational changes in the receptor. The results obtained lead to a logical model for the angiotensin receptor allowing for normal activation by the hormone as well as for production of tachyphylaxis.  相似文献   
6.

Ethnopharmacological relevance

Campomanesia species are used in folk medicine as anti-inflammatory, anti-rheumatic, anti-diarrheal and hypocholesterolemic.

Aim of the study

The present study investigated the in vivo anti-inflammatory and antinociceptive properties of ethyl acetate (AE) and aqueous (Aq) extracts from leaves of Campomanesia adamantium and in vitro anti-inflammatory activity of AE and its isolated flavonols, myricitrin and myricetin.

Materials and methods

The antinociceptive activity of AE and Aq was evaluated using acetic acid-induced writhing and formalin methods. The in vivo anti-inflammatory effect of AE and Aq was evaluated using carrageenan-induced paw oedema in mice. AE, myricitrin and myricetin were evaluated for their abilities to modulate the production of NO, TNF-α and IL-10 in LPS/IFN-γ stimulated J774.A1 macrophages.

Results

It was found that orally administrated AE and Aq (125 and 250 mg/kg) inhibited carrageenan-induced paw oedema in mice. AE (125 and 250 mg/kg) and Aq (125 mg/kg) reduced the time to licking at the second phase of the formalin method in vivo in mice. AE (250 mg/kg) and Aq (125 mg/kg) also reduced the number of writhes. AE, myricitrin and myricetin inhibited NO (320 μg/mL and 6.25–100 μM, respectively) and TNF-α production by macrophages (320 μg/mL for AE, 100 μM for myricitrin and 25–100 μM for myricetin). AE (160 and 320 μg/mL), myricitrin (50 and 100 μM) and myricetin (25–100 μM) increased IL-10 production by macrophages.

Conclusions

The ethyl acetate and aqueous extracts from Campomanesia adamantium showed antinociceptive and anti-inflammatory effects supporting the use of the plant in folk medicine. The results suggest that anti-oedematogenic effect promoted by aqueous extract involves several anti-inflammatory mechanisms of action. The antinociceptive effect shown by aqueous extract can be due to the modulation of release of inflammatory mediators involved in nociception. The anti-inflammatory effects of AE and of its isolated flavonols may be attributed to inhibition of pro-inflammatory cytokines production, TNF-α and NO and to the increased of IL-10 production.  相似文献   
7.

Purpose

To study the β-catenin gene in a group of Mayer-Rokitansky-Küster-Hauser patients.

Methods

Twelve patients with the Mayer-Rokitansky-Küster-Hauser syndrome were included in this study. DNA was extracted from peripheral blood and the region codifying β-catenin GSK-3β phosphorylation sites on exon 3 was amplified. PCR products were purified and directly sequenced.

Results

No mutations were found in the GSK-3β phosphorylation sites on exon 3 of β-catenin gene in this group of patients with the MRKH syndrome.

Conclusions

β-catenin gene mutations are an unlikely cause of the MRKH syndrome.  相似文献   
8.

Objectives

To evaluate autonomic symptoms and function in Friedreich’s Ataxia (FRDA).

Methods

Twenty-eight FRDA patients and 24 controls underwent clinical/electrophysiological testing. We employed the Friedreich’s Ataxia Rating Scale (FARS) and the Scales for Outcomes in Parkinson’s Disease: Autonomic Questionnaire-SCOPA-AUT to estimate the intensity of ataxia and autonomic complaints, respectively. Cardiovagal tests and the quantitative sudomotor axonal reflex, Q-SART, were then assessed in both groups.

Results

In the patient group, there were 11 men with mean age of 31.5?±?11.1?years. Mean SCOPA-AUT score was 15.1?±?8.1. Minimum RR interval at rest was shorter in the FRDA group (Median 831.3?×?724.0?ms, p?<?0.001). The 30:15 ratio, Valsalva index, E:I ratio, low and high frequency power presented no differences between patients and controls (p?>?0.05). Sweat responses were significantly reduced in patients for all sites tested (forearm 0.389?×?1.309?µL; proximal leg 0.406?×?1.107?µL; distal leg 0.491?×?1.232?µL; foot 0.265?×?0.708?µL; p value?<?0.05). Sweat volumes correlated with FARS scores.

Conclusions

We found abnormal sudomotor but normal heart rate variability in FRDA. Small cholinergic post-ganglionic fibers are affected in the disease.

Significance

Quantification of sudomotor function might be a biomarker for FRDA.  相似文献   
9.
This study analyzed serum thyroglobulin (Tg) during hypothyroidism in 207 patients with differentiated thyroid carcinoma treated with total thyroidectomy and radioiodine ablation and undetectable anti-Tg antibodies. Disease staging was defined by clinical examination, stimulated Tg, pre- and post-ablative radioiodine scanning, and other imaging methods (X-Ray, US, CT and MIBI-scan). The average interval from initial therapy was 2.3 years. 153 patients (74%) had no evident disease, 34 (16.4%) presented neck/mediastinal disease, and 20 (9.6%) had distant metastases (Mt). The best cut-off for Tg was 1 ng/ml, showing 100% sensitivity for distant Mt and 88.2% for local recurrence or lymph node Mt, and 88.8% specificity for any Mt and 74.8% for distant Mt. In patients with Tg <1 ng/ml, 2.8% showed cervical lymph nodes Mt. Cervical or mediastinal disease were 26% of cases with Tg between 1 and 5 ng/ml. Tg from 5 to 10 ng/ml was associated to distant Mt in 14.2% of the cases and others showed lymph nodes Mt. In patients with Tg >10 ng/ml, 51.3% presented distant Mt. We suggest the need for neck US even in cases with Tg <1 ng/ml. In addition, patients with Tg levels <5 ng/ml should be investigated by neck US and mediastinal CT only, and empirical therapy should be limited to patients with a minimum Tg level >5 ng/ml.  相似文献   
10.
4-Nerolidylcatechol (4-NC) is found in Pothomorphe umbellata root extracts and is reported to have a topical protective effect against UVB radiation-induced skin damage, toxicity in melanoma cell lines, and antimalarial activity. We report a comparative study of the antioxidant activity of 4-NC and α-tocopherol against lipid peroxidation initiated by two free radical-generating systems: 2,2′-azobis(2-aminopropane) hydrochloride (AAPH) and FeSO4/H2O2, in red blood cell ghost membranes and in egg phosphatidylcholine (PC) vesicles. Lipid peroxidation was monitored by membrane fluidity changes assessed by electron paramagnetic resonance spectroscopy of a spin-labeled lipid and by the formation of thiobarbituric acid-reactive substances. When lipoperoxidation was initiated by the hydroxyl radical in erythrocyte ghost membranes, both 4-NC and α-tocopherol acted in a very efficient manner. However, lower activities were observed when lipoperoxidation was initiated by the peroxyl radical; and, in this case, the protective effect of α-tocopherol was lower than that of 4-NC. In egg PC vesicles, malondialdehyde formation indicated that 4-NC was effective against lipoperoxidation initiated by both AAPH and FeSO4/H2O2, whereas α-tocopherol was less efficient in protecting against lipoperoxidation by AAPH, and behaved as a pro-oxidant for FeSO4/H2O2. The DPPH (2,2-diphenyl-1-picrylhydrazyl) free-radical assay indicated that two free radicals were scavenged per 4-NC molecule, and one free radical was scavenged per α-tocopherol molecule. These data provide new insights into the antioxidant capacity of 4-NC, which may have therapeutic applications for formulations designed to protect the skin from sunlight irradiation.  相似文献   
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