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51.
Peripheral T‐cell lymphoma (PTCL) is rare in children, and it has a poor prognosis compared with other types of lymphoma. We report the case of a 7‐year‐old boy with spontaneous improvement of PTCL complicated by hemophagocytic syndrome as the initial symptom. He complained of pain and swelling of the right neck and presented with high fever. Pancytopenia, liver dysfunction, elevated ferritin and soluble interleukin 2 receptor were noted on laboratory tests. Peripheral blood plasma and white blood cells were positive for Epstein–Barr virus (EBV) genome but, after several days, the fever abated and laboratory data improved. On histopathology of lymph node biopsy, he was diagnosed as having PTCL not otherwise specified (PTCL‐NOS) with EBV infection. He received no chemotherapy and was disease free at the last follow up, 6 years 8 months after onset. This is probably the first case of spontaneous improvement in PTCL‐NOS. Careful treatment planning is therefore necessary in PTCL‐NOS, given the possibility of spontaneous improvement of symptoms.  相似文献   
52.
The management of LSRS is a crucial problem to ensure a sufficient PV flow during pediatric LT. Although several techniques have been indicated to solve this problem, a more appropriate approach to LSRS is still needed in pediatric LT. We herein present a modified surgical approach to the ligation of LSRS via the left side of the IVC for a nine‐month‐old boy with severe portal hypertension and a history of Kasai portoenterostomy. LSRS was identified and exposed through the left side of the IVC and the dorsal surface of the pancreas from the superior side of the body of the pancreas. The post‐operative course was uneventful with an excellent PV flow. The central approach for the ligation of LSRS is worth considering as an alternative procedure for a patient with collateral vessels and a history of multiple laparotomies.  相似文献   
53.
PC is produced in the liver and inhibits blood coagulation by catalyzing active factors V and VIII. PC deficiency causes abnormal blood clotting that is difficult to regulate by anticoagulative treatments. Four reports of PC deficiency treated with LTx have been published; however, no report of DLT as a therapy for PC deficiency is available. We describe a case of a 23‐month‐old girl who received DLT for compound heterozygous PC deficiency. Her PC activity was below 5%. She developed intracranial lesion and frequent refractory purpura fulminans. Both her parents had heterozygous mutations of PC genes and were excluded as living donors. Furthermore, she was a low priority on the waiting list of deceased‐donor transplantation. We performed living DLT using the liver from a patient with MSUD. Activated PC concentrate safely supported the perioperative period. After DLT, she maintained normal PC activities and BCAA levels. This is the first case of PC deficiency successfully treated by living DLT with MSUD. We propose that DLT using liver from patients with MSUD is a treatment option for PC deficiency.  相似文献   
54.
An inhibitory mechanism toward gastrin hypersecretion is significantly different between G‐cell hyperplasia and gastrinoma despite the common clinical manifestations; hypergastrinemia and its related persistent gastric ulcers. We recenlty studied the G‐cell, d ‐cell and ECL‐cell density in a case of G‐cell hyperplasia. The 70‐year‐old patient has been treated for persistent gastric ulcers with a markedly increased plasma gastrin (5600 pg/mL). The stomach was surgically resected because of the obstruction associated with ulcer scars. The number of G‐cells in the pyloric glands was quantified on the surgical specimens and G‐cell hyperplasia was histolopathologically identified. Immunostainig of histidine decarboxylate revealed the presence of ECL‐cell hyperplasia in the pyloric glands and its density was significantly and positively correlated with G‐cell density. Somatostatin immunoreactive cells (d ‐cells) increased in their number in the oxyntic glands. These results all indicated that hypersecretion of gastrin in G‐cell hyperplasia could induce ECL‐cell proliferation in a paracrinal manner. In addition, relatively non‐prominent endocrinological features in the G‐cell hyperplasia compared to gastrinoma could be also related to the paracrinal somatostatin inhibitory effects upon ECL‐cells in the pyloric glands.  相似文献   
55.
56.
Clinical Rheumatology - To evaluate the ability of geldanamycin to modulate two opposing TNFα/TNFR1-triggered signals for inflammation and cell death. The effects of geldanamycin on...  相似文献   
57.
Both intravascular ultrasound (IVUS) and optical coherence tomography (OCT) play a crucial role in elucidating the pathophysiology of coronary artery disease (CAD) with the goal to improve patient outcomes of medical and/or interventional CAD management. However, no single intravascular imaging technique has been proven to provide complete and detailed evaluation of all CAD lesions due to some limitations. Although sequential use of multiple modalities may sometimes be performed, there may be issues related to risk, time, and cost. To overcome these problems, several hybrids involving dual-probe combined IVUS-OCT catheters have been developed.The aim of this review article is to demonstrate some limitations of stand-alone imaging devices for evaluation of CAD, summarize the advances in hybrid IVUS-OCT imaging devices, discuss the technical challenges, and present the potential value in the clinical setting, especially in patients receiving medical or interventional CAD management.  相似文献   
58.
BackgroundNo established methodology exists for diagnosis of aortic stenosis (AS) using focused cardiac ultrasound (FOCUS). We evaluated the diagnostic accuracy of our developed visual AS score for screening AS in an emergency department.MethodsSeventy-two emergency outpatients with suspected cardiovascular disease were studied. Emergency physicians assessed the visual AS score in addition to conducting the standard FOCUS, and then the aortic valve area index (AVAI) was measured by expert sonographers in the echocardiography laboratory. AVAI values >0.85 cm2/m2, 0.6–0.85 cm2/m2, and <0.6 cm2/m2 were defined as no or mild AS, moderate AS, and severe AS, respectively.ResultsSeventeen (24%) patients had moderate or severe AS. Visual AS scores assessed by emergency physicians and by expert sonographers showed excellent agreement (κ = 0.93), and a strong association was noted between the visual AS score assessed by emergency physicians and the AVAI assessed by expert sonographers (R = –0.71, p < 0.0001). A visual AS score ≥3 assessed by emergency physicians had a sensitivity of 82%, specificity of 100%, positive predictive value of 100%, and negative predictive value of 95% for diagnosing moderate or severe AS. The prevalence of new-onset AS-related events during hospitalization was higher in patients with visual AS score ≥3 assessed by emergency physicians than in the remaining patients [7 (50%) vs. 2 (3%), p < 0.0001].ConclusionThe visual AS score is a useful AS screening tool for emergency physicians who are not expert cardiologists.  相似文献   
59.
We previously characterized the patients with autosomal recessive hypercholesterolemia (ARH) as having severe hypercholesterolemia and retarded plasma low-density lipoprotein (LDL) clearance despite normal LDL receptor (LDLR) function in their cultured fibroblasts, and we identified a mutation in the ARH locus in these patients. ARH protein is an adaptor protein of the LDL and reportedly modulates its internalization. We developed ARH knockout mice (ARH-/-) to study the function of this protein. Plasma total cholesterol level was higher in ARH-/- mice than that in wild-type mice (ARH+/+), being attributed to a 6-fold increase of LDL, whereas plasma lipoprotein was normal in the heterozygotes (ARH+/-). Clearance of 125I-LDL from plasma was retarded in ARH-/- mice, as much as that found in LDLR-/- mice. Fluorescence activity of the intravenously injected 1,1'-dioctadecyl-3,3,3',3'-tetramethylindocarbocyanine perchlorate (DiI)-LDL was recovered in the cytosol of the hepatocytes of ARH+/+ mice, but not in those of ARH-/- or LDLR-/- mice. Also, less radioactivity was recovered in the liver of ARH-/- or LDLR-/- mice when [3H]cholesteryl oleyl ether (CE)-labeled LDL was injected. In contrast, uptakes of [3H]CE-labeled LDL, 125I-LDL, and DiI-LDL were all normal or slightly subnormal when the ARH-/- hepatocytes were cultured. We thus concluded that the function of the hepatic LDLR is impaired in the ARH-/- mice in vivo, despite its normal function in vitro. These findings were consistent with the observations with the ARH homozygous patients and suggested that certain cellular environmental factors modulate the requirement of ARH for the LDLR function.  相似文献   
60.
We describe a gastric carcinoma cell line that has been maintained in vitro for more than 10 years and retains the capacity to produce a large amount of alpha-fetoprotein. This cell line was isolated from a metastatic lymph node of a 63-year-old male patient with advanced gastric carcinoma (T2N3P0H0M0) who showed high serum levels of alpha-fetoprotein. The primary tumor was moderately differentiated tubular adenocarcinoma and the lymph node was poorly differentiated adenocarcinoma without any particular pattern. The cultured cells grew as densely packed islet-like colonies with small polygonal cells. Electron microscopy revealed cells abundant in cytoplasmic organelles, with some cellular attachments being tight with junctional complexes and some being loose across intercellular spaces. The free cell surface had microvilli. The population doubling-time was 152 h at passage 58. Chromosomal analysis revealed the modal number to be 77, with numerous karyotype abnormalities. The tumorigenicity of the cultured cells in athymic nude mice was positive only when they were subcutaneously transplanted beneath a plastic plate, but when the cells were transplanted subcutaneously or administered by intrasplenic injection in intact or weakly irradiated nude mice, no tumorigenicty was shown. The cell line produced tumor-associated antigens, such as alpha-fetoprotein, carcinoembryonic antigen, and tissue polypeptide antigen. This cell line may be useful for comparative studies of different types of gastric carcinoma and alpha-fetoproteins of different origins.  相似文献   
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