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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.
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   
65.
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   

66.
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   
67.
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   
68.

Background

Burden of headache has been assessed in adults in countries worldwide, and is high, but data for children and adolescents are sparse. The objectives of this study were o develop a questionnaire and methodology for the global estimation of burden of headache in children and adolescents, to test these in use and to present preliminary data.

Methods

We designed structured questionnaires for mediated-group self-administration in schools by children aged 6-11 years and adolescents aged 12-17 years. In two pilot studies, we offered the questionnaires to pupils in Vienna and Istanbul. We performed face-to-face interviews in a randomly selected subsample of 199 pupils to validate the headache diagnostic questions.

Results

Data were collected from 1,202 pupils (mean 13.9 ± 2.4 years; 621 female, 581 male). The participation rate was 81.1% in Istanbul, 67.2% in Vienna. The questionnaire proved acceptable: ≤5% of participants disagreed partially or totally with its length, comprehensibility or simplicity. The sensitivity, specificity, positive and negative predictive values ranged between 0.71 and 0.76 for migraine and between 0.61 and 0.85 for tension-type headache (TTH). Cronbach’s alpha was 0.83. The 1-year prevalence of headache was 89.3%, of migraine 39.3% and of TTH 37.9%. The prevalence of headache on ≥15 days/month was 4.5%. One fifth (20.7%) of pupils with headache lost ≥1 day of school during the preceding 4 weeks and nearly half (48.8%) reported ≥1 day when they could not do activities they had wanted to. The vast majority of pupils with headache experienced difficulties in coping with headache and in concentrating during headache. Quality of life was poorer in pupils with headache than in those without.

Conclusion

These pilot studies demonstrate the usefulness of the questionnaires and feasibility of the methodology for assessing the global burden of headache in children and adolescents, and predict substantial impact of headache in these age groups.  相似文献   
69.
目的分析并探讨高钠血症对重型颅脑损伤患者预后产生的影响及处理对策。方法对我院自2007年11月至2010年10月期间收治的78例重型颅脑损伤后伴高钠血症患者的临床资料做回顾性分析。78例患者按血清钠水平分为高血钠组及高血钠组。结果全部78例重型颅脑损伤患者中继发高钠血症者37例,发生高钠血症组的GCS评分为3~5分者30例,GCS评分为6~8分者7例,两组相比差异显著(P〈0.01),具有统计学意义。高钠血症患者有27例死亡,10例生存,两组的病死率相比,差异亦显著(P〈0.01),具有统计学意义。结论患者高钠血症的病情程度和GCS分值具有密切的相关性。对于高钠血症,临床工作中必须充分提高预防意识,重视其严重后果尽早采取纠正高钠血症措施,在保守治疗无效的情况下,应尽早开始血液净化治疗,改善患者的预后。  相似文献   
70.
T-gamma lymphoproliferative disease (T-gamma LPD) is a chronic disorder of mature T cells that is associated with neutropenia and autoimmune phenomena. Although the progression of the lymphoproliferation is indolent, it is often associated with a monoclonal proliferation of T- cell-type large granular lymphocytes (LGL) that manifest multiple in vitro suppressor and cytotoxic activities. We considered the possibility that the granulocytopenia or anemia might represent an autoimmune disorder mediated by the monoclonal LGL via T-cell receptor (TCR) recognition of an antigen involved in hematopoiesis. Therefore, in an effort to characterize the usage of the TCR alpha- and beta-chain genes in patients with T-gamma LPD, we cloned and sequenced TCR alpha- and beta-chain mRNAs derived from the T-cell type LGL of five patients. The five patients studied did not use a common V alpha nor a common J alpha segment. However, an unusual finding was observed in one of the patients where the occurrence of a single variable-diversity-junctional (VDJ) rearrangement of the beta chain confirmed the monoclonal origin of the LGL proliferation. In accord with this evidence for monoclonality, many of the cells studied used a common V alpha (V alpha 19.1). In contrast to this common V alpha usage, there was a marked diversity of the J alpha segments and N-region addition that were associated with the V alpha 19.1 segment. This pattern of common V alpha usage associated with different N and J alpha segments suggests an immune-mediated selection process affecting the TCR alpha chain occurring after the transformation event that established the clone. We suggest that the T-cell-type LGL malignant clone might have developed autoreactivity conferred by the selected TCR alpha chain and that this autoreactivity might be implicated in this patient's anemia.  相似文献   
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