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991.
992.
Acute mediastinitis is a fatal disease that usually originates from esophageal perforation and surgical infection. Rare cases of descending necrotizing mediastinitis can occur following oral cavity and pharynx infection or can be a complication of pancreatitis. The most common thoracic complications of pancreatic disease are reactive pleural effusion and pneumonia, while rare complications include thoracic conditions, such as pancreaticopleural fistula with massive pleural effusion or hemothorax and extension of pseudocyst into the mediastinum. There have been no reports of acute mediastinitis originating from pancreatitis in South Korea. In this report, we present the case of a 50-year-old female suffering from acute mediastinitis with pleural effusion arising from recurrent pancreatitis that improved after surgical intervention.  相似文献   
993.
Five new dimeric ent-kauranoids, biexcisusins A-E (1-5), were isolated from the aerial parts of Isodon excisus. The structures and relative configurations of these compounds were determined on the basis of spectroscopic data interpretation. Of these, biexcisusins C-E (3-5) are dimeric ent-kaurane diterpenoids exhibiting an unprecedented linkage through a nine-membered lactone ring between two ent-kaurane subunits. Compounds 1-5 showed no inhibitory effects on the LPS-induced production of nitric oxide in murine macrophage RAW264.7 cells, up to a dose of 50 μM.  相似文献   
994.
995.
We investigated pseudoprogression (psPD) in patients with malignant gliomas treated with radiotherapy (RT) and maintenance temozolomide (TMZ) in terms of incidence, outcomes, and predictive and prognostic factors. We evaluated p53 overexpression by immunohistochemical analysis of thirty-five tumor samples as a predictor for psPD. The time to progression and overall survival were compared between subgroups, psPD versus early progression (ePD) versus nonprogression (nonPD). Eight patients developed psPD among eighteen patients with lesion enlargement at the first MRI scan, and the others were classified as ePD. The remaining stable or improved patients were classified as nonPD. All patients with psPD were alive at last follow-up (median follow-up period was 12 months; range 5.8–58.5 months). Overall survival of psPD patients was significantly higher than ePD patients (P < 0.01). There was no significant survival difference between the psPD group and nonPD group (P = 0.25). Seven (87.5%) of eight tumors with psPD showed p53 overexpression, as compared to 3 (30%) of the ten tumors with ePD (P = 0.03). Our study indicates that psPD following chemoradiotherapy with TMZ is associated with significantly better overall survival compared to that of ePD, and is comparable to nonPD group. Overexpression of p53 was identified as a potential biomarker for predicting the development of psPD.  相似文献   
996.
The effect of cyclosporin A (CsA), an immunosuppressant, on human ether-a-go-go-related gene (HERG) channel as it is expressed in human embryonic kidney cells was studied using a whole-cell, patch-clamp technique. CsA inhibited the HERG channel in a concentration-dependent manner, with an IC(50) value and a Hill coefficient of 3.17 μM and 0.89, respectively. Pretreatment with cypermethrine, a calcineurin inhibitor, had no effect on the CsA-induced inhibition of the HERG channel. The CsA-induced inhibition of HERG channels was voltage-dependent, with a steep increase over the voltage range of the channel opening. However, the inhibition exhibited voltage independence over the voltage range of fully activated channels. CsA blocked the HERG channels predominantly in the open and inactivated states rather than in the closed state. Results of the present study suggest that CsA acts directly on the HERG channel as an open-channel blocker, and it acts independently of its effect on calcineurin activity.  相似文献   
997.
1. In mice, acetylcholine (ACh) plays an important role in oocyte activation and embryonic development. However, the role of ACh in mouse oocyte maturation has not been investigated. 2. In the present study, the effects of 100 μmol/L and 1 mmol/L ACh on maturation processes of murine germinal vesicle (GV) intact oocytes (GV oocytes) exposed to 10 and 100 μmol/L 3-isobutyl-1-methylxanthine (IBMX), an inhibitor of cyclic nucleotide phosphodiesterase, were evaluated morphologically and immunologically. It has been shown that IBMX inhibits the resumption of meiosis by preventing cAMP breakdown. 3. In the present study, at the start of in vitro culture 100% of oocytes were at the GV stage. After 18 h culture, 95 ± 3, 0 and 85.8 ± 10.2% of oocytes had passed the GV stage in the control, IBMX and IBMX + ACh groups, respectively. The IBMX-induced inhibition of the maturation process was significantly attenuated by approximately 90% by ACh in groups treated with 10 μmol/L IBMX + 100 μmol/L ACh and 100 μmol/L IBMX + 1 mmol/L ACh. Although cAMP levels were high in oocytes treated with 100 μmol/L IBMX, levels were reduced in groups treated simultaneously with 100 μmol/L ACh. Furthermore, compared with mature oocytes, ACh-treated GV oocytes exhibited significantly lower (by approximately 2.3-fold) or absent Ca(2+) peaks. 4. The results of the present study indicate that maturation of GV oocytes, arrested by IBMX treatment, is resumed following ACh treatment and that this effect is due to downregulation of cAMP rather than changes in intracellular Ca(2+) levels.  相似文献   
998.
The Division of Vaccine-Preventable Disease Control and National Immunization Program of the Korea Centers for Disease Control and Prevention has prepared a plan of action as a guide for key actions that will be taken if a poliovirus outbreak occurs in the Republic of Korea. The history of poliomyelitis and vaccination against poliovirus in the nation was reviewed and the routine surveillance procedures that are currently in place were described. The principles and specific actions for an effective response to a poliovirus outbreak were prepared. The guidelines clearly outline the actions to be taken in case of a polio outbreak. When a suspected case of poliovirus infection is reported, an immediate epidemiological investigation is to be conducted. The response to a poliovirus outbreak includes case isolation, management of potential contacts and immunization. All stakeholders are to be made aware of what key actions should be taken at each stage of the response to a poliovirus outbreak in the nation.  相似文献   
999.
Click chemistry is a useful approach for the preparation of novel radiopharmaceuticals. In this study, we evaluated 4-[18F]fluoro-1-butyne as a radiolabeled synthon for click chemistry with azido compounds. Our results showed that nucleophilic substitution of 4-tosyloxy-1-butyne with K[18F]F produces vinyl acetylene as well as 4-[18F]fluoro-1-butyne, while the same reaction using 5-tosyloxy-1-pentyne gives exclusively 5-[18F]fluoro-1-pentyne. Thus, ω-[18F]fluoro-1-alkynes with chain lengths longer than four carbons may be better radiolabeled synthons for use in click chemistry.  相似文献   
1000.
AIM:To evaluate seroprevalence of hepatitis A virus (HAV) antibody and investigate demographic,clinical,and laboratory features of recent cases in Korea.METHODS:For the evaluation of hepatitis A seroprevalence,we analyzed the data from 3127 subjects including,healthcare workers and patients who visited Konkuk University Hospital,a secondary referral center,from January to October 2009.The sera with positive IgM were excluded from seroprevalence data for total HAV antibody.We retrospectively reviewed the electronic medical records of 419 patients with HAV,who were diagnosed by the presence of serum IgM antibodies against HAV.All patients presented at Konkuk University Hospital between August 2005 and September 2008.RESULTS:Among 3127 sera tested,1428 (45.7%)were positive for anti-HAV antibody.The seroprevalence was very low in teenagers or those in their twenties,increased in those in their thirties,and was > 90% in older patients.In children younger than 10 years,seroprevalence was increased again.Most patients with HAV hepatitis were in their twenties and thirties.The γ-glutamyl transpeptidase increased with age and was significantly higher in patients older than 30 years.Indicators of severity,such as decreased albumin and increased bilirubin,were also more prominent in the older age group;however,the leukocyte count was higher and the frequency of leukopenia was lower in younger patients than in older adults.CONCLUSION:There has been an apparent epidemiological shift in HAV seroprevalence and a change in the peak age of HAV hepatitis.This study could provide baseline data of recent hepatitis A in Asia.  相似文献   
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