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1.

Background

Persistent iatrogenic atrial septal defect (iASD) is a common but poorly characterized complication after cryoballoon (CB) pulmonary vein isolation (PVI) procedures. We therefore investigate its prevalence, evolution, risk factors, and clinical outcomes in a prospective longitudinal study.

Methods

A total of 108 patients (41 women, mean age 57 ± 11.3) underwent CB PVI for AF. Serial transesophageal echocardiography (TEE) was performed 9 months and then annually until 6 years after the procedure to study the characteristics of persistent iASD.

Results

Persistent iASD occurred in 33 (30.6%) patients 9 months after CB PVI. Spontaneous closure of iASD was found in 6 (22.2%) and 3 (15.8%) patients 2 and 3 years after the procedures, respectively. No spontaneous closure was observed on 4, 5, and 6-year TEE follow-up. The projected long-term persistence rate of iASD after CB PVI was therefore 20% (30.6% × 0.778 × 0.842). Using multivariate logistic regression, a higher number of cryoapplications (≥ 2 minutes) was the only independent predictor of persistent iASD 9 months after CB PVI (odds ratio [OR] 1.207; 95% confidence interval [CI], 1.033-1.411, P = 0.018). Two (1.9%) patients with significantly larger iASD size than the others (long diameter 12.6 ± 0.8 vs 3.7 ± 1.5 mm, P < 0.001; short diameter 10.9 ± 0.2 vs 3 ± 1.1 mm, P < 0.001) required percutaneous closure because of exertional dyspnea and right ventricular enlargement. Over 129.7 patient-years follow-up, during which iASD persisted, there was no occurrence of neurologic events.

Conclusions

Approximately one fifth of patients undergoing CB PVI will have permanently persistent iASD. Patients with defect sizes of greater than 10 mm may need percutaneous closure due to significant left-to-right shunting.  相似文献   
2.
Background. This study is intended to determine the causes of pediatric traumatic brain injuries (PTBI) in children aged 14 years or less, and to identify various types of craniocerebral damage resulting from different mechanisms of injury.Methods. From July 1, 1993 to June 30, 2001, a survey on PTBI was conducted in Taiwan. The data of patients used in this study were collected from 56 major hospitals among the age group of 0-14 years. The items in the traumatic brain injury survey included sex, age, causes of injuries, severity, and the eventual outcome.Results. A total of 5349 cases were identified. The male-to-female ratio was 1.69: 1. The incidence rate was higher in the age groups of 4-9 years and 10-14 years. The main cause of PTBI was traffic injury, which accounted for 2537 of the cases (47.3%), followed by falls, 2160 (40.3%). Of all traffic injuries, motorcycle-related injury had the highest incidence, followed by the pedestrian and bicycle-related injury. This study also showed that 83.2% of the patients had mild injury, 9.8% had moderate injury, and 7.0%, severe injury.Conclusions. The results of this study suggest that it is important to decrease all the risk factors in the environment of homes and public areas as much as possible. Helmet wearing and the development of public transportation are essential for the prevention of head injury.  相似文献   
3.
J C Nitz  N L Low Choy 《Climacteric》2007,10(5):408-415
OBJECTIVES: The purpose of this study was to report habitual physical activity levels in women and document the change in level of activity and factors affecting this change over a 5-year period. METHODS: A 5-year prospective cohort design was used. Women aged 40-80 years, living independently in the community, were recruited via the electoral role. The effects were investigated, first, of age, activity level, history of falls, number of co-morbidities and medications, body mass index and stability at baseline on change in activity level and, second, change in these demographics on activity level over the study period. RESULTS: Data from 459 women who completed our study are reported. Only activity level and body mass index at baseline significantly affected change in activity level (p<0.000). Change in activity level was not influenced by change in demographics over the study period. The forties and fifties cohorts accounted for the baseline body mass index effect on activity change (p<0.04). In the forties cohort, number of medical conditions at base line (p<0.03) and, in the sixties cohort, increase in number of medical conditions (p=0.011) affected activity level change. CONCLUSIONS: Activity level at baseline and body mass index in younger women were most likely to affect change over time. Being unsteady or having already fallen did not stimulate change.  相似文献   
4.
A method for embeddingPneumocystis carinii in hydrophilic resin (London Resin White) has been developed for immunocytochemistry studies. Using high osmotic pressure (about 850 mosmol) from fixation to embedding, this method improved the preservation of the fine structure as well as the antigenicity of rabbit-and SCID mouse-derivedP. carinii. Cytochemistry studies were performed using colloidal gold-conjugated lectins (concanavalin A, glycine max,Ulex europaeus) that reacted with the cytoplasmic components (endoplasmic reticulum, Golgi vesicles). Colloidal gold-conjugated streptavidin was also tested and was found to be reactive with the parasite cell wall and cytoplasmic components, which precludes its indiscriminate use inP. carinii immunocytochemistry studies.This investigation was supported in part by the Agence Nationale de Recherche sur le SIDA (ANRS). The senior author (F.P.) was awarded a scholarship from the Conseil Régional Nord-Pas de Calais  相似文献   
5.
6.
Tumor necrosis factor (TNF) was produced in mice bearing Ehrlich ascites tumor (EAT) by priming with zymosan and subsequently challenging with lipopolysaccharide. The optimal conditions for the in vivo production of TNF in treating EAT bearing mice were established. The endotoxin shock induced in mice during TNF production could be minimized by the combined administration of sulindac and mannoheptulose. The endogenous TNF produced could suppress proliferation of EAT cells as well as prolong the survival time of mice bearing small tumors.  相似文献   
7.
The early results of brachytherapy for persistent and recurrent nasopharyngeal carcinoma in 30 patients is presented. Fifteen patients were treated by intracavitary caesium, 12 patients were treated by interstitial gold grain implant using the split-palate approach and three patients were treated by both intracavitary caesium and interstitial gold grain implant for the first and second relapse in the nasopharynx, respectively. The overall tumour control rate for intracavitary caesium was 5/18 (28%) with median follow-up of 25.2 months, and for interstitial gold grain implant it was 9/14 (64%) with median follow-up of 16.5 months. Interstitial gold grain implantation appears to be effective in the treatment of persistent and recurrent nasopharyngeal carcinoma.  相似文献   
8.
The phagocytic activity of human first trimester extravillous trophoblast   总被引:20,自引:3,他引:17  
It has been suggested previously that phagocytic activity inthe human placenta is confined to cells of the macrophage lineage.However, earlier studies were hampered by the paucity and poorviability of cells inherent in primary trophoblast cell cultures,contamination by other cell types which themselves have phagocyticactivity, lack of reliable markers of trophoblasts, and by limitationsof methods available to demonstrate unequivocally the internalizationof particulate material. We have overcome these limitationsby using: (i) DNA transfection to provide unlimited suppliesof pure trophoblast cell lines; (ii) human placental lactogenas a marker unique to trophoblast; and (iii) confocal microscopyof demonstrate unequivocally the intracellular locality of phagocytosedmaterial. We found that both untransfected primary culture extravilloustrophoblast cells, as well as the cell lines, had the capacityto phagocytose sheep red blood cells, Staphylococcus aureusand baker's yeast cells, and that this activity was inhibitedby cytochalasin B and by culture at 4°C. Phagocytic activityin trophoblast cells was less avid than that seen in a professionalphagocyte. In physiological and pathological situations wheretissue remodelling occurs, such as the rapid turnover in theperiodontal ligament or during inflammation, epithelial cellsand other cells that are not considered professional phagocytesactively phagocytose components of the extracellular matrix.We postulate that phagocytosis by human trophoblasts may playan important role in the extensive tissue remodelling that occursduring trophoblastic invasion of the decidua.  相似文献   
9.
Either a percutaneous-transvesical, a transvaginal, or a perurethral-transvesical approach can be used for oocyte recovery under ultrasound guidance in an in vitro fertilization and embryo transfer program. After having experienced these three different approaches in our program, we preferentially used the perurethral-transvesical approach as our routine technique for oocyte recovery under ultrasound guidance. We feel that this method is easier to perform and also carrier less risk for contamination. From January to December 1986, 186 oocyte retrievals under ultrasound guidance were performed. In 7 cases no oocytes were found despite normal ovarian stimulation. A total of 767 oocytes was collected; the fertilization rate was 71.8%. Forty pregnancies were achieved (21.5% per attempt or 27.7% per embryo replacement). Except for transient hematuria, no complications were observed.  相似文献   
10.
By means of a PCR assay, EBV was demonstrated directly in peripheral blood of previously infected individuals. The virus was detected in approximately 80% of specimens from EBV-seropositive individuals, but not in cord-blood lymphocytes by this method. When virus present in peripheral blood was compared to that observed directly in NPC biopsies or throat washings, it was distinct from that seen in biopsies in 4/15 cases (27%) and from that seen in throat washes in 1/22 cases (5%). The throat-wash virus differed from the biopsy virus in 3/20 cases (15%). The prototype F virus was found in 7/10 LCLs (70%) established from NPC patients' peripheral blood, but was only detected in 2/9 specimens (22%) directly analyzed by the PCR assay. This finding suggests selective isolation of prototype F EBV in spontaneous LCLs established from NPC patients.  相似文献   
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