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61.
Unipolar Characteristics of CFAEs. Background: The noncontact mapping (NCM) system possesses the merit of global endocardial recording for unipolar and activation mapping. Objective: We aimed to evaluate the unipolar electrogram characteristics and activation pattern over the bipolar complex fractionated atrial electrogram (CFAE) sites during atrial fibrillation (AF). Methods: Twenty patients (age 55 ± 11 years old, 15 males) who underwent NCM and ablation of AF (paroxysmal/persistent = 13/7) were included. Both contact bipolar (32–300 Hz) and NCM virtual unipolar electrograms (0.5–300 Hz) were simultaneously recorded along with the activation pattern (total 223 sites, 11 ± 4 sites/patient). A CFAE was defined as a mean bipolar cycle length of ≤ 120 ms with an intervening isoelectric interval of more than 50 ms (Group 1A, n = 63, rapid repetitive CFAEs) or continuous fractionated activity (Group 1B, n = 59, continuous fractionated CFAEs), measured over a 7.2‐second duration. Group 2 consisted of those with a bipolar cycle length of more than 120 ms (n = 101). Results: The Group 1A CFAE sites exhibited a shorter unipolar electrogram cycle length (129 ± 11 vs 164 ± 20 ms, P < 0.001), and higher percentage of an S‐wave predominant pattern (QS or rS wave, 63 ± 13% vs 35 ± 13%, P < 0.001) than the Group 2 non‐CFAE sites. There was a linear correlation between the bipolar and unipolar cycle lengths (P < 0.001, R = 0.87). Most of the Group 1A CFAEs were located over arrhythmogenic pulmonary vein ostia or nonpulmonary vein ectopy with repetitive activations from those ectopies (62%) or the pivot points of the turning wavefronts (21%), whereas the Group 1B CFAEs exhibited a passive activation (44%) or slow conduction (31%). Conclusions: The bipolar repetitive and continuous fractionated CFAEs represented different activation patterns. The former was associated with an S wave predominant unipolar morphology which may represent an important focus for maintaining AF. (J Cardiovasc Electrophysiol, Vol. 21, pp. 640‐648, June 2010)  相似文献   
62.
目的:研究野茼蒿的挥发性成分。方法:用固相微萃取(solid-phase microextrations,SPME)和气相色谱-质谱(gas chromatography-mass spectrometry,GC-MS)联用仪对野茼蒿的挥发性成分进行测定。结果:从中共鉴定出37种化学成分。含量最多的3种成分是月桂烯(61.609%)、牛儿烯D(6.481%)、α-葎草烯(6.293%)。结论:茼蒿主要挥发性成分为烯烃。  相似文献   
63.
针对药学专业物理化学实验教学中存在的问题,从优化实验项目与内容、改进数据处理方法、探索新的教学模式、贯彻绿色环保理念等方面探讨改革思路。  相似文献   
64.
李佳  魏波  塔娜  陈必良 《医学争鸣》2009,(22):2500-2502
目的:探讨链脲佐菌素(STZ)建立妊娠期糖尿病(GDM)大鼠模型中不同给药剂量对模型稳定性的影响,研究GDM对母体及胎儿的影响率、转阴率和死亡率.方法:将46只SD孕鼠随机分为STZ低、中、高不同剂量组,分别一次性腹腔注射STZ35,45,60mg/kg;对照组腹腔注射等量的柠檬酸缓冲液.于妊娠第3,9,14,19d时测空腹血糖,并观察成模孕鼠在妊娠中体质量、饮水量、摄食量和尿量变化,比较孕鼠成模情况.结果:STZ45mg/kg组孕鼠在用药后出现明显的“三多一少”症状,其成模率83.3%为最高,转阴率最低.空腹血糖值STZ45mg/kg组(21.8±3.0)mmol/L与对照组(5.9±1.2)mmol/L相比较,其高血糖状态持续时间长,最稳定,且体质量也明显降低,差异具有统计学意义(P〈0.05).结论:STZ45mg/kg腹腔注射给药是建立GDM大鼠模型的最佳剂量,具有较好的稳定性.  相似文献   
65.
生活方式改善对预防糖尿病的重要作用   总被引:1,自引:0,他引:1  
塔娜  张国庆  呼和 《中外医疗》2009,28(23):168-169
营养过剩、肥胖.缺少运动是糖尿病发病的重要原因。本文针对这些原因阐述了防止肥胖、控制饮食和增加运动等生活方式的改善对预防糖尿病的重要作用。  相似文献   
66.
目的了解呼和浩特市餐饮单位餐具消毒状况,分析不同规模餐饮单位餐具消毒效果。方法采用大肠菌群快速检测纸片法,抽取2005-2007年本市餐饮单位消毒后备用餐具进行检测。结果3年共检测餐具7957份,合格率为64.28%;大、中、小型餐饮单位合格率分别为74.59%、65.32%和36.33%;大中专院校食堂合格率为68.21%。结论呼和浩特市餐具消毒总体合格率较低,应加大执法力度,加强监测频率,尤其要督促搞好学校食堂餐具消毒工作。  相似文献   
67.
Background: Halo nevus (HN) is a rare dermatologic disorder characterized by typical whitish rim surrounding an existing melanocytic nevus resembling halo. It is a cosmetic problem that may be linked to vitiligo, and it is advised to remove these nevi in order to avoid development of vitiligo.

Objectives: The aim of the present study is to evaluate the cosmetic outcome after nevus removal and leukoderma dermabrasion with epithelial graft followed by narrow-band ultraviolet B (NB-UVB) phototherapy as management of resistant halo nevi and avoidance of development of vitiligo.

Patients and Methods: Ten patients with persisting halo nevi were selected as candidates in this study. Superficial dermabrasion was carried out using proper diamond fraises on depigmented rim and then punch biopsy probes with suitable size were used to harvest the nevus. Thiersch graft was prepared and applied on the dermabraded depigmented area. After 1 week of the procedure, patients were exposed to NB-UVB twice weekly and were followed up for 3 months.

Results: Repigmentation was noticed in 2 weeks and was nearly fully accomplished in all 10 patients within the 3-month period. No other vitiligo lesions developed during this period in all patients except for one case.

Conclusion: Excision of Sutton’s nevus with combined dermabrasion and Thiersch grafting followed by phototherapy is a good aesthetic maneuver in treating halo nevi and helps in avoiding further vitiligo depigmentation.  相似文献   

68.
OBJECTIVE: The changing healthcare environment world-wide is leading to extensive use of per case payment systems based on diagnosis-related groups (DRG). The aim of this study was to examine the impact of application of different DRG systems used in the German healthcare system. METHODS: We retrospectively analysed 2334 clinical data sets of inpatients discharged from an academic dermatological inpatient unit in 2003. Data were regarded as providing high coding quality in compliance with the diagnosis and procedure classifications as well as coding standards. The application of the Australian AR-DRG version 4.1, the German G-DRG version 1.0, and the German G-DRG version 2004 was considered in detail. To evaluate more specific aspects, data were broken down into 11 groups based on the principle diagnosis. MAIN OUTCOME MEASURE: DRG cost weights and case mix index were used to compare coverage of inpatient dermatological services. Economic impacts were illustrated by case mix volumes and calculation of DRG payments. RESULTS: Case mix index results and the pending prospective revenues vary tremendously from the application of one or another of the DRG systems. The G-DRG version 2004 provides increased levels of case mix index that encourages, in particular, medical dermatology. CONCLUSIONS: The AR-DRG version 4.1 and the first German DRG version 1.0 appear to be less suitable to adequately cover inpatient dermatology. The G-DRG version 2004 has been greatly improved, probably due to proceeding calculation standards and DRG adjustments. The future of inpatient dermatology is subject to appropriate depiction of well-established treatment standards.  相似文献   
69.
We studied the effect of HLA-C matching in 515 patients after double umbilical cord blood (UCB) transplantation. After HLA matching HLA-A, -B, and -DRB1 at the allele level, we scored patients according to number of donor-recipient HLA-C matches at 4 possible loci: 2 from each donor unit, at the allele level. Given a direct interaction between HLA-A, -B, and -DRB1 matching and HLA-C score, we analyzed HLA-C matching in those receiving at least 1 2/6 to 4/6 HLA–matched unit (n?=?389) versus those receiving only 5/6 or 6/6–matched units (n?=?126). In those with at least 1 2/6 to 4/6 HLA–matched unit, a better HLA-C matching score was associated with significantly lower risk of death of any cause and nonrelapse mortality and better disease-free survival. There was no association with the risk of relapse, acute and chronic graft-versus-host disease, and hematopoietic recovery. In contrast, among patients receiving only allele-level 5/6 or 6/6 HLA–matched UCB units, HLA-C match had no demonstrable effect on any outcome. For patients receiving at least 1 allele-level 2/6 to 4/6 HLA–matched UCB unit, matching at HLA-C reduces nonrelapse mortality and improves survival.  相似文献   
70.
Lane  TA; Lamkin  GE 《Blood》1986,68(2):351-354
We previously showed that an artificial blood substitute containing perfluorocarbons, Fluosol-DA, inhibited both neutrophil migration and adherence, due to its detergent component, Pluronic F-68. The purpose of the studies we report here was to determine if Fluosol or Pluronic might also reduce in vivo neutrophil migration and impair host resistance to bacterial infection. We studied in vivo PMN migration by injecting mice intraperitoneally (IP) with glycogen, followed by intravenous (IV) infusion of saline, Fluosol, or Pluronic. Peritoneal lavage after eight hours showed a significant decrease in the accumulation of PMN in lavage fluids of animals given either Fluosol or Pluronic (control--.19 +/- .03 X 10(6) PMN/mL, glycogen--1.35 +/- .14; glycogen/Fluosol--0.63 +/- .12; glycogen/Pluronic--0.69 +/- .07). We ascertained the effect of Fluosol and Pluronic on infection mortality by injecting mice IV with saline, Fluosol, or Pluronic, followed by a quantity of E coli (0.6 X 10(7] IP shown in preliminary studies to kill 20% to 50% of the mice in 24 hours. The 24-hour mortality was 14/45- saline, 24/32-Fluosol (chi 2 = 17.1; P less than .001) and 17/23 - Pluronic (chi = 11.2; P less than .001). Neither Fluosol nor Pluronic caused mortality without E coli. The increase in infection mortality occurred when Fluosol was given either two hours before, or simultaneously with E coli, but only with the simultaneous administration of bacteria and Pluronic. Pluronic did not alter reticuloendothelial system (RES) clearance function. These studies indicate that, in an animal model, Fluosol-DA, due to its detergent component Pluronic F-68, impaired neutrophil delivery to an inflammatory locus, and resulted in an increased rate of infection mortality. Since Pluronic did not result in RES blockade, but did impair the delivery of PMN to an inflammatory locus, our results suggest that the latter effect is responsible for the increase in infection mortality.  相似文献   
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