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991.
Silvana Jukić Krmek Ivana Bogdan Paris Simeon Goranka Prpić Mehičić Davor Katanec Ivica Anić 《Lasers in medical science》2010,25(6):823-828
The aim of this study was to evaluate microleakage along resin restoration in cavities prepared with an erbium:yttrium–aluminium–garnet
(Er:YAG) laser, with and without acid etching, and to compare it with that in diamond-drilled cavities. Thirty intact molars
were divided into three equal groups. In the teeth in group I, class V cavities were prepared with a diamond drill. Cavities
in groups II and III were prepared with an Er:YAG laser (400 mJ/15 Hz for enamel and 250 mJ/10 Hz for dentine). The cavities
in groups I and II were acid-etched and adhesive and flowable composite were applied to all cavities. The specimens were first
immersed in dye for 24 h and then in 5% nitric acid for 72 h for softening. The fillings were extracted and photographed through
a dissecting microscope. The leakage area was measured with specially designed software. The Kruskal–Wallis test showed that
the best ranking was group II [mean range (m.r.) = 27.46], followed by group I (m.r. = 33.48) and, lastly, group III (m.r. = 45.15).
The differences between groups I and III (P = 0.023) and between groups II and III were statistically significant (P = 0.080). The least microleakage was found in those cavities prepared by Er:YAG laser and subsequently acid-etched, whereas
the most leakage was in the lased cavities that had not been etched; the traditional diamond-drilled acid-etched cavities
produced medium leakage. 相似文献
992.
Petr Peichl Robert Čihák Markéta Koželuhová Dan Wichterle Vlastimil Vančura Josef Kautzner 《Journal of interventional cardiac electrophysiology》2010,27(1):51-59
Background
Frequent episodes of polymorphic ventricular tachycardias/ventricular fibrillation (VT/VF) in patients with coronary artery disease can be triggered by monomorphic ventricular premature beats (VPBs) and thus, amenable to catheter ablation. The goal of this study was to review single-center experience in catheter ablation of electrical storm caused by focally triggered polymorphic VT/VF. 相似文献993.
Erkan Parlak Selçuk Dişibeyaz Cem Cengiz Bahattin Çiçek Yasemin Özin Sabite Kacar Nurgül Şaşmaz Burhan Şahin 《BMC gastroenterology》2010,10(1):142
Background
Ectopic opening of the common bile duct into the duodenal bulb (EO-CBD-DB) is a rare disease that may be complicated by duodenal ulcer, deformity, stenosis and biliary stones. The aim of this study is to report clinical presentations, endoscopic diagnosis and treatment of this entity as well as to investigate its association with duodenal stenosis. 相似文献994.
Zorica Cvetković Vesna Vučić Bora Cvetković Milan Petrović Danijela Ristić-Medić Jasna Tepšić Maria Glibetić 《Annals of hematology》2010,89(8):775-782
The data about the fatty acid (FA) status of non-Hodgkin lymphoma (NHL) patients are poor. Therefore, the aim of this study was to investigate the FA profile of serum phospholipids in NHL patients related to the aggressiveness and clinical stage of NHL. We analyzed the FA profile of serum phospholipids in 47 newly diagnosed, untreated NHL patients and in 29 healthy subjects. Significantly higher (p?<?0.001) levels of palmitic (16:0), oleic (18:1 n-9) and arachidonic acids (20:4 n-6), saturated and monounsaturated FA were found in NHL patients, while linoleic acid (18:2 n-6) and the levels of total polyunsaturated FA (PUFA), n-3 PUFA, eicosapentaenoic (20:5 n-3) and docosahexaenoic (DHA, 22:6 n-3) were significantly reduced (p?<?0.01). The level of oleic acid in patients with indolent NHL was significantly lower (p?<?0.05) than in more aggressive types of disease. Contents of palmitoleic acid, docosatetraenoic (22:4 n-6), and PUFA was lower in very aggressive NHL. According to clinical stage (CS), patients with CS I had significantly higher SFA and lower n-6 FA than other three groups, and group with CS IV showed significantly decreased DHA and n-3 PUFA. Our results showed an abnormal FA profile in serum phospholipids in NHL patients. 相似文献
995.
Zinnamosca L Petramala L Cotesta D Marinelli C Sciomer S Cavallaro G Ciardi A Massa R De Toma G Filetti S Letizia C 《Endocrine》2010,38(3):313-319
Primary aldosteronism (PA) with synchronous carcinoid syndrome is extremely rare occurrence. In this article, we describe a case of PA due to adrenocortical adenoma ("aldosteronoma") and concurrent malignant carcinoid tumor of ileum. The patient was treated with synchronous right adrenalectomy and resection of the ileum. This case is an example of concomitant presence of two types of tumors, effectively managed surgically. We report a case of a nonclassical form of multiple endocrine neoplasia type 1 (MEN 1) syndrome. 相似文献
996.
Kamil Vysloužil Pavel Zbořil Pavel Skalický Katherine Vomáčková 《International journal of colorectal disease》2010,25(2):259-265
Purpose
The aim of this study was to determine whether overactivity of the anal sphincter in patients with hemorhhoids is primary or secondary and thus assess indication of lateral internal sphincterotomy to surgical treatment of hemorrhoids. Tonic contraction of the sphincter muscle in patients with advanced stages of hemorrhoids is considered by many authors as a primary cause, and therefore, they complete hemorrhoid surgery with lateral internal sphincteroomy. If hypertension of anal sphincter is secondary during hemorrhoid disease, lateral internal sphincterotomy is not indicated. Although examinations made immediately after sphincterotomy proved no changes of anal continence, certain sequelae of lateral internal sphincterotomy cannot be excluded and may later negatively affect patient’s anal continence. 相似文献997.
G. Leposavić V. Pešić Z. Stojić-Vukanić K. Radojević N. Arsenović-Ranin D. Kosec M. Perišić I. Pilipović 《Experimental gerontology》2010
Alpha1-adrenoceptors (α1-ARs) are involved in neuro-thymic and thymic intercellular communications, and consequently modulation of T-cell development. Ageing is associated with a number of changes in noradrenergic neuro-effector transmission, and possibly intercellular noradrenaline (NA)-mediated communication resulting in altered responses of target cells to NA. Thus, in old animals an altered NA modulation of thymopoiesis via α1-ARs may be expected. To test this hypothesis, in old and young adult Wistar rats we examined: 1) thymic NA levels, density of noradrenergic innervation and NA synthesizing cells, as well as α1-AR expression, and 2) then the effects of 14-day-long treatment with the α1-AR blocker, urapidil, on thymocyte development. Overall, the first part of study suggested augmented NA signalling to thymic cells via α1-ARs due to increased NA availability and α1-AR thymocyte surface density in old rats. The second part of study supported this assumption. Namely, although in rats of both ages urapidil affected the same thymocyte developmental steps ultimately leading to changes in the relative number of the most mature single positive TCRαβhigh thymocytes, its effects were generally more prominent in old animals. Following urapidil treatment, the percentages of CD4 + CD8− cells, including those showing a regulatory CD4 + CD25 + RT6.1− phenotype, were increased, while CD4 − CD8+ cells decreased. In old rats, an augmented thymic escape of immature CD4 + CD8+ cells was also registered. In rats of both ages the thymic changes were accompanied by alterations in the proportions of major cell populations in the T-lymphocyte compartment of both peripheral blood and spleen, leading to an increase in the CD4+/CD8+ T-cell ratio. These alterations were also more pronounced in old rats. Moreover, in old rats following urapidil treatment the proportion of TCRαβ + cells in the periphery was slightly greater reflecting, most likely, partly enhanced thymic production of regulatory CD161 + TCRαβ + cells. Thus, the study indirectly suggests an age-associated increase in the basal α1-AR-mediated inhibitory influence of NA on thymopoiesis. 相似文献
998.
In this study, the potential of lecithin/chitosan nanoparticles (NPs) as colloidal nanosystem for transdermal melatonin delivery was investigated. Mean diameter and zeta-potential of NPs differing in lecithin type (Lipoid S45 and S100) and chitosan content ranged between 113.7 and 331.5?nm and 4.6 and 31.2?mV, respectively. Melatonin loadings were up to 7.2%. The potential of lecithin/chitosan NPs to enhance transdermal melatonin delivery was investigated by determining the drug flux across dermatomed porcine skin and its skin deposition. Lecithin/chitosan NPs provided 1.3-2.3-fold higher flux compared to melatonin solution. The highest flux, 9.0?±?0.21?μg/cm2/h, was observed for S45 lecithin/chitosan NPs with lecithin/chitosan weight ratio of 20:1. NP possible cytotoxicity in vitro was evaluated using human skin keratinocytes and fibroblasts. It was demonstrated that lecithin/chitosan NPs can be applied to skin cells at concentrations up to 200?μg/mL without inducing plasma membrane damage or cell viability decrease. 相似文献
999.
Tomić M Vasković D Tovilović G Andrić D Penjišević J Kostić-Rajačić S 《Archiv der Pharmazie》2011,344(5):287-291
Five groups of previously synthesized and initially screened non-substituted and 4-halogenated arylpiperazin-1-yl-ethyl-benzimidazoles were estimated for their in-vitro binding affinities at the rat D(2) , 5-HT(2A) , and α(1) -adrenergic receptors. Among all these compounds, 2-methoxyphenyl and 2-chlorophenyl piperazines demonstrate the highest affinities for the tested receptors. The effects of 4-halogenation of benzimidazoles reveal that substitution with bromine may greatly increase the affinity of the compounds for the studied receptors, while the effect of substitution with chlorine is less remarkable. Most of the tested components show 5-HT(2A)/D(2) pK(i) binding ratios slightly above or less than 1, while only 4-chloro-6-(2-{4-[3-(trifluoromethyl)phenyl]piperazin-1-yl}ethyl)-1H-benzimidazole expresses an appropriate higher binding ratio (1.14), which was indicated for atypical neuroleptics. This compound exhibits a non-cataleptic action in rats and prevents d-amphetamine-induced hyperlocomotion in mice, which suggest its atypical antipsychotic potency. 相似文献
1000.
Systems for storage and distribution of purified water at ambient temperature are highly susceptible to microbial contamination. The water flow, microbial content and chemical quality of the purified water in an industrial water system have been simulated in a biofilm annular reactor (BAR) to study the impact of different hydrodynamic conditions on biofilm development. Our results reveal the potential of stagnant purified water at total organic compounds (TOC) below 50ppb to develop biofilm that allows detachment of planktonic bacteria and colonization of new surfaces within 24h. However, under constant water flow over 7 days, the growth of initial biofilm was 40 times less, fewer bacteria were detached, and new surfaces were colonized to a lesser extent. Heterotrophic plate counts (HPCs) in biofilm were highly positively correlated with numbers of detached planktonic bacteria in effluent water. The study shows that the hydrodynamic conditions and level of planktonic HPC in water are critical for the development of biofilm at very low TOC. The results in the BAR agreed well with those from regular industrial microbial monitoring of purified water. To conclude, the BAR successfully simulates biofilm growth and can be used to establish an effective biofilm control strategy. However, the microbial quality of purified water in industrial system is a constant challenge; any increase of HPC in effluent water is a sign to take steps against excessive microbial growth. 相似文献