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71.
Previous studies have shown that external ultrasound with low frequencies and high intensities can enhance thrombolytic drug-induced clot dissolution during in vitro experiments. In this series of studies, we evaluated the efficacy of peripheral and coronary thrombolysis in vivo in animals by using noninvasive transcutaneous ultrasound combined with thrombolytic drugs (streptokinase and tPA) and/or microbubbles agents (dodecafluoropentane [DDFP] and perfluorocarbon-exposed sonicated dextrose albumin [PESDA]). Thrombotic occlusions were induced in 74 rabbit iliofemoral arteries and 24 canine left anterior descending (LAD) coronary arteries in this in vivo study. By using the combination of transcutaneous ultrasound and streptokinase, the angiographic patency rate in rabbit iliofemoral arteries was higher (56%-100%) than with ultrasound (6%; P < or = 0.0036) and streptokinase alone (6%; P < or = 0.0012). Also, with transcutaneous ultrasound and microbubbles, the angiographic patency rates were 76%-100% as compared with ultrasound alone (0%, P < or = 0.0003) or microbubbles alone (9%, P < or = 0.0001). In the canine study of acute myocardial infarction, thrombolysis in myocardial infarction (TIMI) grade flow at 90 minutes in the tPA alone group was 0.92 +/- 1.4 as compared with 2.42 +/- 1.9 in the tPA plus transthoracic ultrasound group (P = 0.006). There was much improved reperfusion with tPA plus ultrasound as compared with tPA alone. In vivo animal studies demonstrate that noninvasive transcutaneous ultrasound can greatly enhance the effect of clot dissolution with thrombolytic drugs and/or microbubbles, and has the potential for clinical application as an adjunctive method to improve arterial thrombolysis.  相似文献   
72.
The aim of this study was to assess the frequency and clinical characteristics of arrhythmogenic right ventricular cardiomyopathy (ARVC) in young victims of sudden cardiac death (SCD). From January 1999 to December 2000, postmortem studies were conducted in 38 cases of SCD (age < or =35 (27+/-7) years old, 26 male) from the Taegu-Kyungpook region of southeastern Korea. Cases of sudden infant death syndrome were excluded. The causes of SCD were ARVC in 42%, acute myocardial infarction in 11%, myocarditis in 11%, pulmonary embolism in 8%, hypertrophic cardiomyopathy in 5%, aortic rupture in 3%, aortic stenosis in 3%, and unknown in 18%. The mean age of the 16 ARVC victims was 27+/-5 years and 10 were male. None were competitive athletes, or had been suspected of having cardiovascular disease before death. SCD was not related to vigorous physical or competitive activity and occurred during sleep in 7 cases, during work in 4, during bathing in 2, while driving, praying and eating in 1 case each. ARVC is an important cause of SCD in young people in this area of Korea.  相似文献   
73.
74.
In China, Japan, and Korea, placenta hominis extracts (PHEs) are used clinically for the treatment of osteoporosis. The anti-osteoporotic effect of PHEs was studied. The trabecular bone area and thickness in OVX rats decreased by 50% from those in sham-operated rats; these decreases were completely inhibited by administration of PHEs for 7 weeks. Osteoclast numbers and the osteoblast surface were enhanced in OVX rats, but PHEs had no effect on these phenomena. Serum phosphorus and alkaline phosphatase in OVX rats increased compared to those in sham-operated rats, but the increases were not affected by the administration of PHEs. Thyroxine (T4) level was stimulated in OVX rats. The extracts inhibited the T4 level in the OVX rats. These results strongly suggest that PHEs be effective in preventing the development of bone loss induced by OVX in rats.  相似文献   
75.
BackgroundIn the past, general surgeons (GSs) without a pediatric surgical subspecialty often performed surgery on children and, even now, GSs are performing many pediatric surgeries. We aimed to investigate the involvement of pediatric surgeons (PSs) and GSs in pediatric surgery, compare the outcomes of surgery in the neonatal intensive care unit (NICU), and estimate the appropriate PS workforce in Korea.MethodsWe used surgical data from the National Health Insurance Service database that was collected from patients under the age of 19 years in hospitals nationwide from January 2002 to December 2017. In this database, we found 37 hospitals where PSs worked by using the index operation (congenital diaphragmatic hernia, esophageal atresia, hypertrophic pyloric stenosis, Hirschsprung''s disease, abdominal wall defect, jejunoileal atresia, malrotation, anorectal malformation, and biliary atresia). It was assumed that the surgery in the 37 hospitals was performed by PS and that the surgery in other hospitals was performed by GS. Mortality was analyzed to compare the outcomes of acute abdominal surgery in the NICU. We estimated the number of PS currently needed in Korea for each situation under the assumption that PS would perform all operations for the index operation, main pediatric diseases (index operation + gastroesophageal reflux disease, choledochal cyst, inguinal hernia, and appendicitis), acute abdominal surgery in the NICU, and all pediatric surgeries. Additionally, we estimated the appropriate number of PS required for more advanced pediatric surgery in the future.ResultsThe number of pediatric surgeries from 2002 to 2017 increased by 124%. Approximately 10.25% of the total pediatric surgeries were performed by PSs, and the percentage of the surgery performed by PSs increased from 8.32% in 2002 to 15.92% in 2017. The percentage of index operations performed by PSs annually was 62.44% in average. It was only 47.81% in 2002, and increased to 88.79% in 2017. During the last 5 years of the study period, the average annual number of surgeries for main pediatric diseases was approximately 33,228. The ratio of the number of surgeries performed by PS vs. GS steadily increased in main pediatric diseases, however, the ratio of the number of surgery performed by PS for inguinal hernia and appendicitis remained low in the most recent years. The percentage of the number of acute abdominal surgery performed by PS in the NICU was 44% in 2002, but it had recently risen to 89.7%. After 30 days of birth, mortality was significantly lower in all groups that were operated on by PS, rather than GS, during the last 5 years. In 2019, 49 PSs who were under the age of 65 years were actively working in Korea. Assuming that all pediatric surgeries of the patients under the age of 19 years should be performed by PS, the minimum number of PS currently required was about 63 if they perform all of the index operations, the main pediatric surgery was about 209, the NICU operation was about 63, and the all pediatric surgeries was about 366. Additionally, it was determined that approximately 165 to 206 PS will be appropriate for Korea to implement more advanced pediatric surgery in the future.ConclusionThe proportion of the pediatric surgery performed by PS rather than GS is increasing in Korea, but it is still widely performed by GS. PSs have better operative outcomes for acute abdominal surgery in the NICU than GSs. We believe that at least the index operation or the NICU operation should be performed by PS for better outcome, and that a minimum of 63 PSs are needed in Korea to do so. In addition, approximately 200 PSs will be required in Korea in order to manage main pediatric diseases and to achieve more advanced pediatric surgery in the future.  相似文献   
76.
BackgroundAlthough electrocardiography and cardiac troponin play important roles in the diagnosis of acute coronary syndrome (ACS), there remain unmet clinical needs. Heart-type fatty acid-binding protein (H-FABP) has been identified as an early diagnostic marker of acute myocardial infarction (AMI). In this study, we examined the diagnostic and prognostic value of H-FABP in patients suspected with ACS.MethodsWe conducted an observational single-center cohort study, including 89 adults aged 30 years or older, who presented to the emergency room (ER) within 24 hours after the onset of chest pain and/or dyspnea. We performed laboratory analysis and point-of-care testing (POCT) for cardiac markers, including H-FABP, troponin I, and creatine kinase-myocardial band. We also evaluated the correlation between cardiac markers and left ventricular (LV) dysfunction and extent of coronary artery disease (CAD).ResultsIn patients presented to ER within 4 hours after symptom onset (n = 49), the diagnostic accuracy of H-FABP for AMI, as quantified by the area under the receiver operating characteristic curve, was higher (0.738; 95% confidence interval [CI], 0.591–0.885) than other cardiac markers. In POCT, the diagnostic accuracy of H-FABP (56%; 95% CI, 45–67) was significantly higher than other cardiac markers. H-FABP was correlated with not extent of CAD but post-AMI LV dysfunction.ConclusionH-FABP is a useful cardiac marker for the early diagnosis of AMI and prediction of myocardia injury. Difference in the circulatory release timeline of cardiac markers could explain its utility in early-stage of myocardial injury.  相似文献   
77.
ObjectiveThe treatment of choice for spinal epidural abscess (SEA) generally is urgent surgery in combination with intravenous antibiotic treatment. However, the optimal duration of antibiotic treatment has not been established to date, although 4–8 weeks is generally advised. Moreover, some researchers have reported that bacteremia is a risk factor for failure of antibiotic treatment in SEA. In this study, we investigated the clinical characteristics of SEA accompanied by bacteremia and also determined whether the conventional 4–8 weeks of antibiotic treatment is sufficient. MethodsWe retrospectively reviewed the medical records and radiological data of 23 patients with bacterial SEA who underwent open surgery from March 2010 to April 2020. All patients had bacteremia preoperatively and underwent weeks of perioperative antibiotic treatments based on their identified organisms until all symptoms of infection disappeared. All patients underwent microbiological studies of peripheral blood, specimens from SEA and concomitant infections. The mean follow-up duration was 35.2 months, excluding three patients who died. ResultsThe male : female ratio was 15 : 8, and the mean age was 68.9 years. The SEA most commonly involved the lumbar spinal segment (73.9%), and the mean size was 2.9 vertebral body lengths. Mean time periods of 8.4 days and 16.6 days were required from admission to diagnosis and from admission to surgery, respectively. Concomitant infections more frequently resulted in delayed diagnosis (p=0.032), masking the symptoms of SEA. Methicillin-sensitive Staphylococcus aureus was the most commonly identified pathogen in both blood and surgical specimens. Seventeen patients (73.9%) showed no deficits at the final follow-up. The overall antibiotic treatment duration was a mean of 66.6 days, excluding three patients who died. This duration was longer than the conventionally advised 4–8 weeks (p=0.010), and psoas or paraspinal abscess required prolonged duration of antibiotic treatment (p=0.038). ConclusionSEA accompanied by bacteremia required a longer duration (>8 weeks) of antibiotic treatment. In addition, the diagnosis was more frequently delayed in patients with concomitant infections. The duration of antibiotic treatment should be extended for SEA with bacteremia, and a high index of suspicion is mandatory for early diagnosis, especially in patients with concomitant infections.  相似文献   
78.
Objective The present study aimed to explore how the patterns of interaction between stress and positive resources differ according to the severity of depression and which resources play the most important role among the various positive resources. Methods The study included 1,806 people who had visited a health screening center for a mental health check-up to evaluate the levels of perceived stress, positive resources, and depressive symptoms. The participants were divided into a depressive group (n=1,642, mean age 50.60, female 68%) and a non-depressive group (n=164, mean age 48.42, female 66.6%). We conducted hierarchical regression analyses and simple slope analyses to examine the interaction between perceived stress and positive resources. Results The interaction between perceived stress and optimism was significantly associated with depression in non-depressive groups. In depressive groups, the interactions between five types of positive resources (optimism, purpose in life, self-control, social support and care) and perceived stress were all significantly related to depression. Conclusion Interventions that promote optimism can be helpful for preventing inevitable stress from leading to depression. A deficiency in positive resources may be a factor in aggravating depression in stressful situations for people reporting moderate to severe depressive symptoms.  相似文献   
79.
ObjectiveTemperament, positive resources, childhood trauma, and other clinical comorbid symptoms are related to depressive symptom severity. Here, we used network analysis to examine the interrelations between these clinical factors in patients with depressive disorders. MethodsPatients with depressive disorders (n=454) completed self-report questionnaires evaluating clinical symptoms, childhood trauma, temperament, and positive resources. To identify network pattern and the most central aspect, we performed network analysis and centrality analyses. First, we analyzed the network pattern in total participants. Second, we established two groups of those with severe depressive symptoms and those with mild depressive symptoms and compared their network patterns. ResultsDeficient optimism and depression were the central factors in the network of total participants. In the group with severe depressive symptoms, lack of social support and childhood emotional trauma showed high centrality. Deficient social support and other positive resources played central roles in the group with mild depressive symptoms. ConclusionNetwork pattern of psychological factors was different between those with mild or severe depression. Lack of positive resources is an important factor in psychological processes in both mild and severe depression. However, childhood emotional trauma may play a relatively important role in patients with severe depressive symptoms.  相似文献   
80.
Elevated blood pressure (BP) is the most common cause of cardiovascular disease. Salt intake has a strong influence on BP, and plasma sodium (pNa) is increased with progressive increases in salt intake. However, the associations with pNa and BP had been reported inconsistently. We evaluated the association between pNa and BP, and estimated the risks of all-cause-mortality according to pNa levels. On the basis of data collected from health checkups during 1995-2009, 97,009 adult subjects were included. Positive correlations between pNa and systolic BP, diastolic BP, and pulse pressure (PP) were noted in participants with pNa ≥138 mM/L (P<0.001). In participants aged ≥50 yr, SBP, DBP, and PP were positively associated with pNa. In participants with metabolic syndrome components, the differences in SBP and DBP according to pNa were greater (P<0.001). A cumulative incidence of mortality was increased with increasing pNa in women aged ≥50 yr during the median 4.2-yr-follow-up (P<0.001). In women, unadjusted risks for mortality were increased according to sodium levels. After adjustment, pNa ≥145 mM/L was related to mortality. The positive correlation between pNa and BP is stronger in older subjects, women, and subjects with metabolic syndrome components. The incidence and adjusted risks of mortality increase with increasing pNa in women aged ≥50 yr.  相似文献   
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