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51.
The Effects of Na~+/Ca~(2+) exchange (NCX) on the Repolarization of Canine Ventricular Myocyte-Potential Arrhythmogenic Effect of NCX during a Mis-matched Repolarization and Relaxation Xiamen Zhongshan Hospital, Xiamen Medical College, Xiamen University@巩燕$Visiting scholar of cardiac arrhythmia research institute,university hospital of Oklahoma!U.S.A
@王焱
@BELA Szabo$Basic cardiac research laboratory,cardiac arrhythmia research institute,university hospital of Oklahoma!… 相似文献
52.
Standardised epidemiological caries assessments used in oral health surveys have been shown to be poor at predicting whether a tooth surface will be treated restoratively when a patient visits a dentist. However, it has been argued that oral health surveys may be more relevant in determining needs at the level of an individual or groups of individuals. The objective of this study was to determine the discriminatory power of visual caries assessments at two thresholds (D1 & D3) in adolescents of average age 12.1 years to predict experience of dentinal caries 3 years later or the experience of restorative treatment (not re‐treatment) during the 3‐year period. The data was derived from a prospective 3‐year longitudinal study in which the dental care provided by 41 dentists for 403 adolescents was monitored. Dental caries experience was monitored by annual standardised assessments of caries undertaken by a single trained examiner. ROC analysis showed that caries assessed visually at the D1 threshold in 12‐year‐olds was a better predictor (P < 0.001) of experiencing some dentinal caries after 3 years (Az = 0.781) than was caries assessed visually at D3 threshold in 12‐year‐olds (Az = 0.670). Assessing caries visually at either the D1 or the D3 threshold had no discriminatory power for predicting whether an individual would experience some restorative treatment during the ensuing 3‐year period (Az for D1 = 0.507; Az for D3 = 0.518). 相似文献
53.
Although psychological debriefing (PD) represents the most common form of early intervention for recently traumatized people, there is little evidence supporting its continued use with individuals who experience severe trauma. This review identifies the core issues in early intervention that need to be addressed in resolving the debate over PD. It critiques the available evidence for PD and the early provision of cognitive-behavioral therapy (CBT). Based on available evidence, we propose that psychological first aid is an appropriate initial intervention, but that it does not serve a therapeutic or preventive function. When feasible, initial screening is required so that preventive interventions can be used for those individuals who may have difficulty recovering on their own. Evidence-based CBT approaches are indicated for people who are at risk of developing posttraumatic psychopathology. Guidelines for managing acutely traumatized people are suggested and standards are proposed to direct future research that may advance our understanding of the role of early intervention in facilitating adaptation to trauma. 相似文献
54.
Tadashi Kano MD Toshiro Koga Kuniyasu Souda Yoshishige Abe Tomohiro Yonemura Naokata Oka Kiyoshi Inokuchi 《Surgery today》1987,17(4):269-275
The usefulness of carcinoembryonic antigen (CEA) as an indicator for recurrence and a guide to the treatment was evaluated
from a retrospective analysis of 88 patients with recurrent gastric cancer. Sixty-two of these patients (70.5 per cent), 25
of whom had a preoperative positive assay, and 37 a negative assay, had elevated levels of CEA after disease progression.
Averaged CEA level in patients with liver metastasis was significantly higher (872 ng/ml) than in those with peritoneal metastasis
(68 ng/ml), with lymph node metastasis (103 ng/ml) or with local metastasis (93 ng/ml) (p<0.01). An elevation of CEA was found
prior to the clinical manifestation of recurrence, and the average lead time was 4 months. In 25 patients with a lead time
of more than 4 months, survival time after CEA elevation was 13.3 months, which was longer than the 6.5 months of 28 patients
with less than 4 months. Thirty-seven of the 88 patients were treated after recurrence. The average survival period after
the detection of recurrence was 9.4 months in patients with surgical treatments followed by chemotherapy, 5.9 months in those
with chemotherapy alone and 3.8 months in those with surgery alone. The average survival period of 26 patients with positive
CEA assays in recurrence was 5.1 months longer than of patients with negative assays. This fact suggested that early detection
of recurrence followed by various treatments, in the elevated CEA group, contributes to favorable results. 相似文献
55.
Nabil El-Sherif 《The International Journal of Cardiac Imaging》1991,7(3-4):141-150
In this work the electrophysiologic mechanisms of ventricular arrhythmias have been briefly summarized. Ventricular arrhytmias can be caused either by pacemaker activity or by reentrant excitation. Enhancement of normal automaticy can generate a parasystolic rhythm in normal fibers. Abnormal automaticity may arise fom fibers in which maximum diastolic potential has been reduced by a variety of interventions. Triggered activity is caused by either an early (EAD) or delayed (DAD) afterdepolarization and requires a prior normal action potential for initiation. While there is growing evidence that EAD-induced triggered activity plays a significant role in the Long QTU syndrome and Torsade de Pointes, no clinical arrhythmias has definitely been ascribed to DADs, although DADs have been recorded in man after acute digoxin intoxication.Ventricular arrhytmias can be also caused by reentrant excitation, which can be subdivided into reflection or circus movement reentry (CMR). In the reflection model impulses in both directions are transmitted over the same pathway. In the CMR three models can be differentiated: the ring model, which requires a fixed anatomical obstacle; the figure-eight model and the leading circle model, where functional rather than fixed anatomical obstacles are involved.Abbreviations AV
atrio-ventricular
- CMR
circus movement reentry
- DAD
delayed afterdepolarization
- EAD
early afterdepolarization
- ECG
electrocardiogram
- LV
left ventricle
- MAP
monophasic action potential
- MF
muscle fiber
- PF
Purkinje fiber
- RV
right ventricle
- TdP
Torsade de Pointes 相似文献
56.
Cognitive models of depression propose that negative schemas contribute to depressive symptoms. Early experiences, particularly parenting, have been proposed to influence cognitive schemas and have also been shown to correlate with depression. This study explores the concurrent relationship between retrospective reports of parenting, Early Maladaptive Schemas (EMSs) described by J. E. Young (1994), and symptoms of depression in a sample of undergraduate students (N = 194). The EMSs of defectiveness/shame, insufficient self-control, vulnerability, and incompetence/inferiority were associated with perceptions of parenting and depressive symptomatology. There was evidence that these four EMSs partially mediate the relationship between parental perceptions and depressive symptomatology. Results are discussed in relation to previous findings, theory, and the measurement of EMSs. 相似文献
57.
Burns during pregnancy: a gloomy outcome 总被引:2,自引:0,他引:2
Amr R. Mabrouk Alaa Eldin H. El-Feky 《Burns : journal of the International Society for Burn Injuries》1997,23(7-8):596-600
The effect of burns on fetal and maternal survival is known to be detrimental. This prospective study describes the performance of pregnant burned patients who were managed and followed up for fetal and maternal outcomes at Ain Shams University's burn unit and Maternity Hospital during the period from October 1995 to September 1996. During the 12-month period, 27 pregnant burned patients were managed. Fetal and maternal mortality correlated with the total body surface area (TBSA) burned, the mortality rate being 63 per cent for both mothers and fetuses in the 25–50 per cent TBSA group. A fetal loss of 56 per cent with no maternal loss were recorded in the 15–25 per cent TBSA group. Experience in dealing with pregnant burned patients proves that early surgical excision and skin grafting, with timely termination of pregnancy are the best lines of treatment. Prevention or minimizing the effects of the burns may be achieved by proper education and guidance of the pregnant woman. 相似文献
58.
59.
Hwang Choi 《Digestive endoscopy》2006,18(1):1-3
Endoscopic technologies have been developed greatly. As for early gastric cancer, the indications for endoscopic mucosal resection for early colorectal cancer have been widened recently. Technological advances can support wider and deeper resections using endoscopy but the remaining problem for the endoscopic management of cancer is lymph node metastasis. I discuss here the indication for endoscopic mucosal resection for early colorectal cancer to bring into focus the risk factors for metastasis to lymph nodes. 相似文献
60.
The external subdivision of the lateral parabrachial nucleus (LPBE) shows strong Fos-like immunoreactivity (FLI) following anorectic doses of the indirect serotonin agonist dexfenfluramine (DFEN). In an effort to determine the contribution of the LPBE to DFEN-induced anorexia, bilateral ibotenate lesions were made in the LPBE, and the effects of the lesion on DFEN-induced anorexia and FLI as well as c-June-like immunoreactivity (JLI) were examined. It was found that LPBE lesion significantly attenuated DFEN anorexia: in a 1-h food intake test following 24-h food deprivation, DFEN (2 mg/kg) suppressed food intake by 60% in intact rats but only 34% in rats with LPBE lesions. In addition to this behavioral change, LPBE lesion completely abolished DFEN-induced FLI and JLI in the lateral subdivision of the central nucleus of the amygdala (CeL) and laterodorsal subdivision of the bed nucleus of stria terminalis (BSTLD), both of which showed strong FLI and JLI in intact rats. DFEN-induced FLI and JLI in other brain regions were not affected by LPBE lesion, including the ventromedial and lateral hypothalamus, caudate-putamen, and the nucleus of the solitary tract (NST). The parallel loss of DFEN-induced anorexia and FLI/JLI following LPBE lesion raises the novel possibility that LPBE-CeL/BSTLD pathway may be involved in DFEN anorexia. 相似文献