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Purpose: The purpose was to demonstrate the leukemiainhibitory factor (LIF) expression in different endometriallocations between fertile and infertile women throughoutdifferent menstrual phases. The relationship betweenprogesterone level and LIF expression were evaluated. Methods: Endometrial biopsies were performed onidiopathic infertile and normal fertile women accepted theinfollicular, periovulatory, and luteal phases. The lutealprogesterone level was measured. Endometrial LIFimmunostaining of luminal epithelium, glandular epithelium, andstroma were detected. The relationship between luteal LIFexpression and progesterone level was evaluated. Results: Significant LIF expression was noted in theendometrium of fertile women rather than that of infertile women.The LIF expression was highest in the luminal epithelium,moderate in the glandular epithelium, and lowest in thestroma. The luminal and glandular epithelial staining werelowest in follicular phase, moderate in periovulatory phase,and strongest in luteal phase. The stromal LIF presentedwith a noncyclical manner. The LIF expression is not relatedwith the progesterone level. Conclusions: Endometrial LIF expression is related tohuman fertility. Endometrial LIF expression is dependenton cellular localizations and menstrual stages. Stronger LIFexpression presents in the endometrial epithelium duringluteal phase.  相似文献   
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The conventional diagnostic procedure of vasography utilizes a contrast medium to evaluate the patency of the vas deferens. With the development of microsurgical reconstruction for obstructive azoospermia in the past two decades, intraoperative vasography with saline or biological dye injection has replaced the use of radiographic contrast media. However, there are few reports on the effect of biological dyes on the healthy vas deferens. Therefore, we used experimental vasography to evaluate histological changes and functional patency of the vas deferens after infusion with a contrast medium and biological dye.
Four groups of 10 Long Evans male rats were injected by vasopuncture with 1% methylene blue, 1% gentian violet and 38% Urografin or saline into the vas deferens. The animals were killed 30 days later, and the vasa deferentia were excised and examined for histological changes and for functional patency. Vasopuncture with saline injection induced minimal change both at the puncture site and in the distal vas deferens. In both the Urografin- and methylene blue-injected groups, inflammation at the puncture site was found in 20–22% of cases, and 10–11% of cases revealed functional obstruction of the vasal lumen. In the gentian violet-injected group, severe histological and obliterated changes were found in all cases. Leakage of the dye and contrast medium or the sperm reaction may be responsible for the inflammation; otherwise, methylene blue and urografin did not seem to be harmful to the vas deferens. Although gentian violet is a blue dye, as is methylene blue, it has marked destructive effects on the vas deferens. It is concluded that some biological dyes used for vasal injection can cause occlusion of the vasal lumen, while inflammatory responses can occur from placing a needle transmurally.  相似文献   
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Conduction Properties of the Crista Terminalis . Introduction: Previous mapping studies in patients with typical atrial flutter have demonstrated the crista terminalis to he a posterior harrier of the reentrant circuit forming a line of block. However, the functional role of the crista terminalis in patients with or without a history of atrial flutter is not well known. The aim of this study was to determine whether the conduction properties of the crista terminalis are different between patients with and those without a history of atrial flutter. Methods and Results: The study population consisted of 12 patients with clinically documented atrial flutter (group 1) and 12 patients with paroxysmal supraventricular tachycardia as well as induced atrial flutter (group 2). A 7-French, 20-pole, deflectable Halo catheter was positioned around the tricuspid annulus. A 7-French, 20-pole Crista catheter was placed along the crista terminalis identified by the recording of double potentials with opposite activation sequences during typical atrial flutter. After sinus rhythm was restored, pacing from the low posterior right atrium near the crista terminalis was performed at multiple cycle length to 2:1 atrial capture. No double potentials were recorded along the crista terminalis during sinus rhythm in both groups. In group 1, the longest pacing cycle length that resulted in a line of block with double potentials along the crista terminalis was 638 ± 119 msec. After infusion of propranolol, it was prolonged to 832 ± 93 msec without change of the interdeflection intervals of double potentials. In group 2, the longest pacing cycle length that resulted in a line of block with double potentials along the crista terminalis was 214 ± 23 msec. After infusion of procainamide, it was prolonged to 306 ± 36 msec with increase of interdeflection interval of double potentials. Conclusion: The crista terminalis forms a line of transverse conduction block during typical atrial flutter. Poor transverse conduction property in the crista terminalis may be the requisite substrate for clinical occurrence of typical atrial flutter.  相似文献   
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Nonlinear Analysis of Atrial Fibrillation . Introduction: Currently, the identification of complex fractionated atrial electrograms (CFEs) in the substrate modification is mostly based on cycle length‐derived algorithms. The characteristics of the fibrillation electrogram morphology and their consistency over time are not clear. The aim of this study was to optimize the detection algorithm of crucial CFEs by using nonlinear measure electrogram similarity. Methods and Results: One hundred persistent atrial fibrillation patients that underwent catheter ablation were included. In patients who required CFE ablation (79%), the time‐domain fibrillation signals (6 seconds) were acquired for a linear analysis (mean fractionation interval and dominant frequency [DF]) and nonlinear‐based waveform similarity analysis of the local electrograms, termed the similarity index (SI). Continuous CFEs were targeted with an endpoint of termination. Predictors of the various signal characteristics on the termination and clinical outcome were investigated. Procedural termination was observed in 39% and long‐term sinus rhythm maintenance in 67% of the patients. The targeted CFEs didn't differ based on the linear analysis modalities between the patients who responded and did not respond to CFE ablation. In contrast, the average SI of the targeted CFEs was higher in termination patients, and they had a better outcome. Multivariate regression analysis showed that a higher SI independently predicted sites of termination (≥0.57; OR = 4.9; 95% CI = 1.33–18.0; P = 0.017). Conclusions: In persistent AF patients, a cycle length‐based linear analysis could not differentiate culprit CFEs from bystanders. This study suggested that sites with a high level of fibrillation electrogram similarity at the CFE sites were important for AF maintenance. (J Cardiovasc Electrophysiol, Vol. 24, pp. 280‐289, March 2013)  相似文献   
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INTRODUCTION: Elimination of the ectopic foci from pulmonary veins (PVs) has proved to be a curative therapy for focal atrial fibrillation (AF). However, information about the importance of the right middle PV (RMPV) in initiation of AF and radiofrequency ablation of AF is limited. METHOD AND RESULTS: Forty-three patients (34 men and 9 women; age 65+/-12 years) with drug-refractory paroxysmal AF underwent electrophysiologic study and catheter ablation for treatment of AF. Three-dimensional magnetic resonance angiography (MRA) of the PVs and left atrium (LA) was performed to determine the anatomic patterns of RMPV. Diameter of PV ostium was measured at the junction of the LA and each PV. MRA findings showed the following: (1) 36 (84%) of 43 patients had a discrete RMPV; (2) there are three drainage patterns of RMPV, including joining the proximal part (<1 cm from the ostium) of the right superior PV (RSPV), joining the right inferior PV (RIPV), and a separate RMPV ostium in the LA wall; and (3) the ostial diameter of RMPV was significantly smaller than RSPV and RIPV (P < 0.01). Electrophysiologic studies demonstrated that five AF foci arose from RMPV. The coupling interval between the ectopic beat of AF and sinus beat was longer in RMPV than RSPV (262+/-45 msec vs 212+/-47 msec; P = 0.043). All AFs from RMPV were ablated successfully. PV stenosis or AF recurrence from RMPV was not found during follow-up of 10+/-4 months. CONCLUSION: RMPV was detected by MRA in >80% of paroxysmal AF patients. Ectopy from RMPV can initiate AF, and radiofrequency ablation of RMPV foci is feasible and safe.  相似文献   
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