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61.
Purpose

To make an in vitro evaluation of the lesion size and depth produced in two different sets of radio frequency energy bipolar delivery: simultaneous biparietal bipolar (SBB) and simultaneous uniparietal bipolar (SUB).

Methods

Two separate prototypes have been built for our purpose: one to be used in SBB mode and the other to be used SUB mode. Forty left atrium samples were taken from the hearts of freshly slaughtered pigs. They were ablated into a simulator ABLABOX, where blood flow, temperature, and contact force were controlled. After being sliced into a cryotome, the samples were digitalized by a flatbed scanner, and the images were analyzed by a computer morphometric software.

Results

Transmural lesions were achieved in 18/20 samples (90%) in SBB, while SUB showed transmurality in 9/20 samples (45%). Overall maximum diameter (DMAX) resulted larger in SUB than in SBB (2.43?±?0.30 mm, 1.62?±?0.14 mm, respectively; p?<?0.05): Moreover, maximum epicardial and endocardial diameters (DEPI and DENDO, respectively) were wider in SUB group than SBB group (2.28?±?0.30 mm, 2.26?±?0.40 and 1.60?±?0.14 mm, 1.59?±?0.15 mm, respectively; p?<?0.05). We observed the same tendency in lesion depth: The total area and volume (ATOT and VTOT) were broader in SUB group than in SBB one (581.01?±?65.38 mm/mm2, 58.10?±?6.53 mm/mm3 and 521.97?±?73.05 mm/mm2, 52.19?±?7.30 mm/mm3. respectively; p?<?0.05).

Conclusions

In contrast with the smaller lesion sizes, the biparietal bipolar group showed a higher transmurality rate. These findings may suggest a better drive of the energy flow when compared with SUB lesions.

  相似文献   
62.
One of the rarest forms of chronic granulomatous disease (CGD) is caused by mutations in CYBA, which encodes the p22-phox subunit of the phagocyte NADPH oxidase, leading to defective intracellular killing. This study investigated eight patients (six males and two females) from seven consanguineous, unrelated families with clinical CGD, positive family history and p22-phox deficiency. Mutation analysis of CYBA showed six different novel mutations: deletion of exons 3, 4 and 5; a missense mutation in exon 6 (c.373G>A); a splice site mutation in intron 5 (c.369+1G>A); a frameshift in exon 6 (c.385delGAGC); a frameshift in exon 3 (c.174delG); and a frameshift in exon 4 (c.223delC).  相似文献   
63.
目的 探讨肋骨内固定手术对多发性肋骨骨折患者的疗效与安全性。 方法 新疆医科大学第六附属医院胸外科2010年1月至2013年1月收治的多发性肋骨骨折患者,选取胸部创伤评分(AIS-ISS评分) 9~20 (16±2)分的患者141例,采用SPSS软件产生的随机序号将患者分为内固定组[69例,男41例、女28例,年龄25~61 (37±4)岁] 和对照组[72例,男43例、女29例,年龄24~63 (35±5)岁],分别行肋骨内固定手术和保守治疗。观察患者血浆C反应蛋白(CRP)水平变化、胸廓外观满意度、肺部炎症发生率、止痛有效率,以及闭式引流时间和住院时间。结果 内固定组CRP水平在伤后1~3 d与对照组差异无统计学意义(P>0.05),在伤后4~12 d内明显低于对照组(P<0.05)。内固定组胸廓外观满意度(97.1% vs. 48.6%,P<0.05)、肺部炎症发生率(11.6% vs. 37.5%,P<0.01)和止痛有效率(91.3% vs. 68.1%, P<0.05)均优于对照组,胸腔闭式引流时间[(3±2) d vs. (7±4) d,P<0.05]和住院时间[(9±4) d vs. (15±7) d,P<0.05]均短于对照组。 结论 对多发性肋骨骨折患者,在生命体征平稳的前提下,采用肋骨内固定手术有利于缩短住院时间和缓解胸痛程度,胸廓外观明显改善,从减轻肺部炎症反应和增加手术安全性的角度提高了多发性肋骨骨折的治疗效果。  相似文献   
64.
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66.
Metabolic Brain Disease - Over the past few decades several attempts have been made to introduce a potential and promising therapy for Multiple sclerosis (MS). Calorie restriction (CR) is a dietary...  相似文献   
67.
IntroductionBlastocystis is a common intestinal parasite of human and animal hosts. The parasite has 17 subtypes, and among those at least nine subtypes (ST1-ST9) are found in human hosts.ObjectiveThe aim of the present study was to investigate the presence of different subtypes of Blastocystis spp. among the patients referred to Velayat hospital of Qazvin province, Iran.MethodsOverall, 864 stool samples were examined by using formalin-ethyl acetate concentration method and Trichrome staining. All specimens were cultured in clotted fetal bovine medium. Later, DNA extraction and PCR amplification of 18S ribosomal RNA gene region was conducted and phylogenetic tree constructed.ResultsThe results revealed 7.9% (68/864) of the study population were infected with Blastocystis. Intestinal symptoms were observed in 61% (36/59) of individuals positive for Blastocystis, with abdominal pain in 58% (21/36) of cases which was more frequent than other intestinal signs. No significant relationship was observed among the study variables. By molecular and phylogenetic analysis, three subtypes ST1 (45%), ST2 (30%) and ST3 (23%) of parasite were identified.ConclusionThis study showed ST1 subtype was the predominant subtype among the positive specimens, meanwhile the highest haplotype and nucleotide diversity were clarified in ST3 subtype.  相似文献   
68.
The applications of DABCO (1,4-diazabicyclo[2.2.2]octane) in the synthesis of piperazine derivatives including biologically active compounds via C–N bond cleavage are investigated in this review. Different reagents such as alkyl halides, aryl(heteroary) halides, carboxylic acids, diaryliodonium salts, tosyl halides, activated alkynes, benzynes etc. were applied for the preparation of the corresponding quaternary ammonium salts of DABCO, which are very good electrophiles for various nucleophiles such as phenols, thiophenols, thiols, alcohols, aliphatic and aromatic amines, sulfinates, phthalimide, indoles, NaN3, triazole and terazoles, NaCN, enols and enolates, halides, carboxylic acid salts etc. Besides preactivated DABCO salts, the in situ activation of DABCO in multicomponent reactions is also an efficient tactic in synthetic organic chemistry for the diversity oriented synthesis of drug-like piperazine derivatives.

The applications of DABCO (1,4-diazabicyclo[2.2.2]octane) in the synthesis of piperazine derivatives including biologically active compounds via C–N bond cleavage are investigated in this review.  相似文献   
69.
Objective:To assess the morphology and dimensions of mandibular symphysis (MS) in different anteroposterior jaw relationships and to investigate whether craniofacial parameters have any correlation with its shape and/or dimensions.Materials and Methods:Lateral cephalograms of subjects with Class I, Class II, and Class III skeletal relationships were traced. Several craniofacial and MS parameters were measured. MS parameters were compared between the three groups using analysis of variance and were correlated with the craniofacial parameters using the Pearson correlation coefficient.Results:Larger angle of concavity of the chin, more inclination of the alveolar bone toward the mandibular plane, and larger MS dimensions and area (P < .001) were found with a Class III skeletal relationship compared to Class I and Class II relationships. The Pearson correlation coefficient between Id-Me and AFH was r  =  0.83 and between Id-Me and LAFH it was r  =  0.81.Conclusions:The dimensions and configuration of MS in the Class III relationship were different than those in Class I and Class II relationships; the alveolar part of MS compensated for the skeletal relationship in the Class III pattern. MS dimensions were strongly correlated to anterior facial dimensions.  相似文献   
70.

Objective

This study has attempted to evaluate the effects of ellagic acid (EA) on alveolar bone healing after tooth extraction in rats.

Design

Twenty-four Sprague Dawley (SD) male rats (200–250 g) were selected and were anaesthetised for the extraction of upper left incisor. Then, the rats were divided into two groups, comprising 12 rats each; the first group has been considered as a control group and was given only normal saline, whereas, the second group (treated group) was intragastrically administrated with EA daily once, for 28 days. Then three rats from each group had been selected on 7th, 14th, 21st, and 28th days to dissect their maxilla tissue either for histological observation and homogenisation purposes. The tissues fixed, decalcified and embedded in paraffin. Serial sections of 5 μm thickness were prepared and stained with haematoxylin and eosin (H&E) for the histological study. Similar sections were taken for immunohistochemical analysis to assess osteocalcin (OSC) and osteopontin (OPN). Furthermore, Malondialdehyde (MDA) and superoxide dismutase (SOD) were measured in homogenated gingival maxilla tissue of rat by commercial kit.

Results

Based on the histological analysis we have identified that, EA treatment has induced earlier trabecular bone deposition in the treated group, resulting in more organised bone matrix on the 14th, 21st, and 28th days after tooth extraction, as against the control group. In comparison to control group, the positive labelling of OSC and OPN of the treated group have been highly expressed in the alveolar socket on 14th, and 21st days, which has indicated a the possibility of formation of new bone trabeculae at the beginning of the mineralisation process, after tooth extraction. In the EA treatment group, lipid per-oxidation (MDA) was significantly decreased (P < 0.05), as opposed to the control group. However, the antioxidant defense enzyme (SOD) was significantly increased in the maxilla tissue treated with EA (P < 0.05), compared to control group, which suggests that, after tooth extraction, EA plays an important role in the protection against the induction of lipid per-oxidation, particularly after 28 days of treatment with EA.

Conclusion

This study has concluded that, EA may accelerated the healing process in teeth socket of rats. Furthermore, the EA treated group showed a stronger positive immunolabelling for OSC and OPN, when compared with the control group.  相似文献   
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