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101.
AIM:To investigate long-term outcome in obscure gastrointestinal bleeding(OGIB) after negative capsule endoscopy(CE) and identify risk factors for rebleeding.METHODS:A total of 113 consecutive patients underwent CE for OGIB from May 2003 to June 2010 at Seoul National University Hospital.Ninety-five patients(84.1%) with a subsequent follow-up after CE of at least 6 mo were enrolled in this study.Follow-up data were obtained from the patients’ medical records.The CE images were reviewed by two board-certified gastroenterologists and consensus diagnosis was used in all cases.The primary outcome measure was the detection of rebleeding after CE,and factors associated with rebleeding were evaluated using multivariate analysis.RESULTS:Of the 95 enrolled patients(median age 61 years,range 17-85 years),62 patients(65.3%) were male.The median duration of follow-up was 23.7 mo(range 6.0-89.4 mo).Seventy-three patients(76.8%) underwent CE for obscure-overt bleeding.Complete examination of the small bowel was achieved in 77 cases(81.1%).Significant lesions were found in 38 patients(40.0%).The overall rebleeding rate was 28.4%.The rebleeding rate was higher in patients with positive CE(36.8%) than in those with negative CE(22.8%).However,there was no significant difference in cumulative rebleeding rates between the two groups(log rank test;P = 0.205).Anticoagulation after CE examination was an independent risk factor for rebleeding(hazard ratio,5.019;95%CI,1.560-16.145;P = 0.007),regardless of CE results.CONCLUSION:Patients with OGIB and negative CE have a potential risk of rebleeding.Therefore,close observation is required and alternative modalities should be considered in suspicious cases.  相似文献   
102.
Fatal complications of Plasmodium falciparum malaria have been reported. However, complicated P. vivax malaria is rare. We observed two unusual cases of P. vivax malaria who presented with clinical pictures of toxic shock. Both showed disseminated intravascular coagulation with marked thrombocytopenia, oliguric renal failure, and pulmonary edema. Examination of initial blood smears showed a P. vivax parasitemia of 2,352/microL and 12,376/microL, respectively. The patients were treated with hydroxychloroquine and primaquine without an antibacterial agent. These cases emphasize the importance of considering the possibility of P. vivax malarial infection in patients with a clinical picture resembling toxic shock if they have a travel history to malaria-endemic areas.  相似文献   
103.
Sera from 491 Korean patients with acute febrile diseases were tested for Ehrlichia chaffeensis and Anaplasma phagocytophila antibodies by indirect immunofluorescence assay (IFA), Western blotting, and TaqMan real-time PCR. Overall, 0.4% of sera reacted with E. chaffeensis, and 1.8% reacted with A. phagocytophila in IFAs. This is the first report of detection of antibodies to A. phagocytophila and E. chaffeensis in Korea and suggests the presence of A. phagocytophila and E. chaffeensis or antigenically similar species.  相似文献   
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Infradiaphragmatic extralobar pulmonary sequestration is an extremely rare congenital malformation. It is more frequently diagnosed in the antenatal period due to routine ultrasonic examination of the fetus or in the first 6 months of life, though on rare occasions it is discovered incidentally in adults. A 32-yr-old man presenting with epigastric discomfort and fever was referred. Computed tomographic scanning showed that a 16-cm, multiseptated, dumbbell-shaped, huge cystic tumor was located beneath the diaphragm. On the next day, 850 mL of thick yellowish pus was drained by sonography-guided fine needle aspiration for the purpose of infection control and diagnosis, but no microscopic organisms were found in repeated culture studies. Surgical removal of the cyst was performed through thoracoabdominal incision and most of these pathologic lesions were removed but we could not find the feeding arteries or any fistulous tract to surrounding structures. Histopathologic study revealed that it was extralobar pulmonary sequestration and culture study showed that many WBC and necrotic materials were found but there were no microorganisms in the cystic contents. We report the first case of an infected infradiaphragmatic retroperitoneal extralobar sequestration which was administered a staged management and achieved an excellent clinical course.  相似文献   
107.
Flavonoids are a family of polyphenolic compounds found ubiquitously in fruits and vegetables as well as in food products and beverages derived from plants. Baicalein is a flavonoid extracted from the root of Scutellaria baicalensis Georgi, a medicinal plant traditionally used in Oriental medicine. Baicalein exerts either proapoptotic or anti-apoptotic effects in different cell types. The present study was, therefore, undertaken to examine the effect of baicalein on cisplatin-induced apoptosis of human glioma cells. Cisplatin resulted in cell death in a dose- and time-dependent manner and the cell death was attributed to apoptosis. Baicalein prevented loss of cell viability and apoptosis induced by cisplatin in a dose-dependent fashion over the concentrations of 2-10 microM. Exposure of cells to baicalein without cisplatin did not affect cell viability. Western blot analysis demonstrated that cisplatin induced activation of extracellular signal-regulated kinase (ERK), which was not affected by baicalein. Baicalein prevented Bax expression, mitochondrial depolarization, cytochrome c release from mitochondria, and caspase activation induced by cisplatin. Taken together, these findings suggest that baicalein prevents cisplatin-induced apoptosis through inhibition of the mitochondrial depolarization in human glioma cells.  相似文献   
108.
Combined radiotherapy and chemotherapy have represented major advance in the therapeutic management of cancer therapy. Anthracycline antineoplastic agents are limited by a high incidence of severe and usually irreversible cardiac toxicity, the cause of which remains controversial. When the primary cardiomyocytes isolated from neonatal rats were preirradiated by γ-ray, the cells were highly resistant to adriamycin-induced apoptosis. This study shows that irradiation inhibited apoptosis by enhancing Bcl-2, attenuating Bax induction, and preventing collapse of mitochondrial membrane potential (ΔΨ), cytochrome c release into cytoplasm and caspase-3, -6 and -9 activations.

In addition, the preirradiation stimulated the activity of manganese-superoxide dismutase (Mn-SOD) and the expression of Mn-SOD mRNA and protein. Adriamycin decreased Mn-SOD activity but did not change the activity of copper/zinc (Cu/Zn)-SOD under either pre- or nonirradiated condition. Phosphothioate-linked antisense against Mn-SOD, which specifically knocked down the activity of Mn-SOD but not that of Cu/Zn-SOD, reversed irradiation-induced protective effect in adriamycin-exposed cardiomyocytes. These data suggest that the irradiation-induced expression of Mn-SOD plays an important role in irradiation-mediated protection in adriamycin-exposed rat ventricular cardiomyocytes.  相似文献   
109.
A monoclonal antibody against human CD43 has been developed and designated as K06. Its reactivity in the lymphoid organs was different from that of known anti-CD43 monoclonal antibodies suggesting that this may recognize a novel epitope of human CD43 molecule. The CD43 epitope detected by anti-K06 monoclonal antibody was highly expressed in cortical thymocytes, platelets, and myeloid cells of normal peripheral blood, and its reactivity was comparable to that of known anti-CD43 monoclonal antibodies. However, the density of this epitope was lower in the medullary thymocytes. Biochemical studies indicated that anti-K06 monoclonal antibody could recognize glycosylated moiety of CD43 antigen. The expression profile of anti-K06 monoclonal antibody in several cell lines was somewhat different from that of known anti-CD43 antibodies. In addition, CD43 ligation through the K06 epitope appeared to induce apoptosis in human leukemic cell line, Molt-4. We therefore assume that K06 epitope of human CD43 might have some role in T-cell development.  相似文献   
110.
Neural stem cells are considered as a candidate for cell replacement therapy in various neurological diseases. To investigate whether human neural stem cells can migrate into the adult ischemic rat brain, we transplanted immortalized human neural ‘tem-like’ cells intravenously 24 h after focal cerebral ischemia. The intravenously injected human neural stem-like cells were found around the infarcted area, differentiated into neurons and astrocytes in the lesioned areas, and survive up to 56 days after transplantation. The number of the injected cells increased between 7 and 14 days after transplantation with incorporating BrdU. Our findings show that intravenously injected human neural stem-like cells may incorporate into the ischemic brain, and undergo proliferation responding to the endogenous mitotic signal during the acute period of focal ischemia.  相似文献   
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