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71.
Porocarcinoma is a rare malignancy with glandular adnexal differentiation. A 38‐year‐old Japanese man noticed a subcutaneous mass in right inguinal region about 20 years prior to being examined. Radiological examinations demonstrated the mass, 11 × 10 cm in size, was in the subcutaneous fat tissue. Recently, the mass grew rapidly, and it was biopsied by an orthopedist based on clinical diagnosis of primary soft tissue tumor. Histopathological examination of the resected specimens also revealed that the tumor lacked involvement to the skin. Microscopically, the tumor was mainly composed of poroid cells with partially obvious squamous differentiation, accompanied by focal ductal structures immunoreactive for CEA and EMA. The tumor contained a low‐grade area consisting of poroid cells and high‐grade area with squamous differentiation. This histopathological heterogeneity suggested malignant transformation from poroma. The patient had the tumor in almost same size over the period of 20 years, which is the longest in the previous reports. This unique case of subcutaneous porocarcinoma is reported.  相似文献   
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We encountered a broadly reactive red cell alloantibody in 1991, reacting unlike any other known antibody, and named it anti-KANNO after the first patient. A total of 28 cases of anti-KANNO in the Japanese literature were reviewed. To distinguish KANNO from other antibodies against high-frequency antigens, including anti-JMH, anti-Ch/Rg, and anti-Jra, we conducted serologic studies with proteolytic enzyme and chemical treatments, complement sensitization against red cells, and serum neutralization techniques. Reactivity of anti-KANNO against red cells lacking high-frequency antigens and antisera to high-frequency antigens against KANNO cells were tested. Among the 28 patients, 26 were female, of whom 25 had a history of pregnancy. Red cells from patient KANNO were reactive with antisera against antigens of high frequency. Anti-KANNO reacted weakly with all cells known to lack high-frequency antigens. It reacted with 2-aminoethylisothiouronium bromide, so it can be distinguished from anti-JMH. Differences among anti-KANNO, anti-Ch/Rg, and anti-Jra emerged with enzyme-treated cells, complement-sensitized cells, and the addition of normal serum. As yet, there are no reports of hemolytic transfusion reaction or hemolytic disease of the fetus and newborn attributable to anti-KANNO. It appears that anti-KANNO is a newly characterized antibody more likely stimulated by pregnancy than by transfusion and with little or no clinical significance. Further surveillance and investigation of anti-KANNO, its antigen biochemistry, and its genetics are warranted.  相似文献   
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Laryngeal cleft is an anomaly of failed posterior closure of the larynx. Most cases are diagnosed and need treatment early in life due to respiratory and swallowing problems. We report an unusual case of a 66-year-old man with an asymptomatic laryngeal cleft until treatment for hypopharyngeal cancer. During concurrent chemoradiotherapy (CCRT), despite reduced tumor volume, he presented severe dysphagia and dyspnea, followed by severe pneumonia twice. Because CCRT had to be discontinued, a pharyngolaryngectomy was performed for the cancer treatment. The resected specimen showed total removal of the tumor and a total longitudinal cleft of the cricoid cartilage, classified as a type III laryngeal cleft by the Benjamin and Inglis’ classification. A review of computed tomography images indicated that the redundant mucosa from bilateral edges closed the separation of the posterior cricoid cartilage and narrowed the laryngeal airway during CCRT. Adult presentations of laryngeal cleft are quite rare with only ten reported cases in English literature; the present case is of the oldest patient. Undiagnosed cases with laryngeal cleft may exist asymptomatically or without severe symptoms. The awareness of this condition may increase its diagnosis as a cause of diseases such as aspiration and recurrent pneumonia even in adult patients.  相似文献   
76.
Immune functions of liver natural killer T (NKT) cells induced by the synthetic ligand alpha-galactosylceramide enhanced age-dependently; hepatic injury and multiorgan dysfunction syndrome (MODS) induced by ligand-activated NKT cells were also enhanced. This study investigated how aging affects liver innate immunity after common bacteria DNA stimulation. Young (6 weeks) and old (50-60 weeks) C57BL/6 mice were injected with CpG oligodeoxynucleotides (CpG-ODN), and the functions of liver leukocytes were assessed. A CpG-ODN injection into the old mice remarkably increased tumor necrosis factor (TNF) production in Kupffer cells, and MODS and lethal shock were induced, both of which are rarely seen in young mice. Old Kupffer cells showed increased Toll-like receptor-9 expression, and CpG-ODN challenge augmented TNF receptor and Fas-L expression in liver NKT cells. Experiments using mice depleted of natural killer (NK) cells by anti-asialoGM1 antibody (Ab), perforin knockout mice, and mice pretreated with neutralizing interferon (IFN)-gamma Ab demonstrated the important role of liver NK cells in antitumor immunity. The production capacities of old mice for IFN-gamma, IFN-alpha, and perforin were much lower than those of young mice, and the CpG-induced antitumor cytotoxicity of liver NK cells lessened. Lethal shock and MODS greatly decreased in old mice depleted/deficient in TNF, FasL, or NKT cells. However, depletion of NK cells also decreased serum TNF levels and FasL expression of NKT cells, which resulted in improved hepatic injury and survival, suggesting that NK cells are indirectly involved in MODS/lethal shock induced by NKT cells. Neutralization of TNF did not reduce the CpG-induced antitumor effect in the liver. CONCLUSION: Hepatic injury and MODS mediated by NKT cells via the TNF and FasL-mediated pathway after CpG injection increased, but the antitumor activity of liver NK cells decreased with aging.  相似文献   
77.
OBJECTIVE: Despite multiple and repeated exposures to HIV-1, some individuals possess no detectable HIV genome and show T-cell memory responses to the viral antigens. HIV-1-reactive mucosal IgA detected in such uninfected individuals suggests their possible immune resistance against HIV. We tested if the above HIV-1-exposed but uninfected status was associated with genetic markers other than a homozygous deletion of the CCR5 gene. METHODS: Based on our mapping in chromosome 15 of a gene controlling the production of neutralizing antibodies in a mouse retrovirus infection, we genotyped 42 HIV-1-exposed but uninfected Italians at polymorphic loci in the syntenic segment of human chromosome 22, and compared them with 49 HIV-1-infected and 47 uninfected healthy control individuals by a closed testing procedure. RESULTS: A significant association was found between chromosome 22q12-13 genotypes and a putative dominant locus conferring anti-HIV-1 immune responses in the exposed but uninfected individuals. Distributions of linkage disequilibrium across chromosome 22 also differed between the exposed but uninfected and two other phenotypic groups. CONCLUSIONS: The data indicated the presence of a new genetic factor associated with the HIV-1-exposed but uninfected status.  相似文献   
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We describe a case of mucosal bile duct carcinoma with superficial spread in a 69-year-old man with gallstone pancreatitis. The patient was seen at the hospital because of abdominal pain, fever, and jaundice. Endoscopic retrograde cholangiography (ERC) demonstrated a protruding lesion in the lower third of the common bile duct (CBD) showing wall irregularity suggestive of malignancy. Percutaneous transhepatic cholangioscopy (PTCS) disclosed a papillary tumor with granular mucosa extending continuously to the middle third of the CBD. Cholangioscopic biopsy specimens taken from both the papillary tumor and surrounding granular mucosa revealed papillary adenocarcinoma. After this assessment of extent of cancer by PTCS, we performed pancreatoduodenectomy with extrahepatic bile duct resection and regional lymph node dissection. Pathology examination revealed papillary adenocarcinoma limited to the mucosal layer. The resected margin of the bile duct was free of tumor. We also reviewed 25 cases of early mucosal bile duct carcinoma described in detail in the Japanese literature, and we discuss the diagnostic advantages of PTCS.  相似文献   
80.
We report on a patient with uncommon-type atrioventricular (AV) nodal reentrant tachycardia with a short tachycardia cycle length (235-270 ms), in whom transient wide QRS tachycardia with both left bundle branch block and right bundle branch block aberrancy were followed by narrow QRS complexes. In addition, His-ventricular (H-V) block and a sudden prolongation of the H-V interval occurred during the tachycardia. As the determinant of these unusual findings, the possibility that the anterograde limb of the reentry circuit has an enhanced AV nodal conduction property is discussed, as is the clinical significance of this type of tachycardia.  相似文献   
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