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71.
Hepatic angiomyolipoma is a rare tumor composed of spindle-shaped and epithelioid smooth muscle cells, adipose tissue, and proliferating blood vessels. We report the first documented case of this tumor developing in a patient with ulcerative colitis. A solitary tumor (7.5×7.5×7cm) was detected in the left lateral segment of the liver and a left hepatic lobectomy was performed. The diagnosis of angiomyolipoma was confirmed by a pathological examination. We also review the literature on previously reported cases of hepatic angiomyolipoma.  相似文献   
72.
Transcatheter arterial embolization (TAE) with the concurrent use of caerulein was assessed for the purpose of preventing gallbladder complications often seen after TAE of hepatic carcinoma. Ninety-six cases with primary hepatic carcinoma, who had undergone TAE in the right hepatic arterial region over the past 4 years, were divided into three groups: 22 cases for which embolization was possible on a selective basis by passing the catheter to the peripheral side beyond the bifurcated region of the cystic artery; 40 cases who had undergone TAE in which caerulein was not administered, from the central side of the bifurcated region of the cystic artery; and 34 cases given 20 g caerulein 15–30 min before TAE. A comparison was made using the abdominal pain, pyrexia, rate of leukocytosis and the US findings of the gallbladder as the indices of the gallbladder complications. As a result, it become evident that it was possible to prevent or alleviate gallbladder complications if caerulein were administered before TAE in cases where the embolizing substances were infused in the right hepatic artery from the central side of the bifurcated region of the cystic artery. It was conclusively shown that the gallbladder blood flow decreases if the organ is contracted by caerulein, which in turn causes a decrease in the inflow of the embolizing substances whereby complications are alleviated.  相似文献   
73.
Sema3A, a prototypical semaphorin, acts as a chemorepellent or a chemoattractant for axons by activating a receptor complex comprising neuropilin-1 as the ligand-binding subunit and plexin-A1 as the signal-transducing subunit. How the signals downstream of plexin-A1 are triggered upon Sema3A stimulation, however, is unknown. Here we show that, in the presence of neuropilin-1, the FERM domain-containing guanine nucleotide exchange factor (GEF) FARP2 associates directly with plexin-A1. Sema3A binding to neuropilin-1 induces the dissociation of FARP2 from plexin-A1, resulting in activation of FARP2's Rac GEF activity, Rnd1 recruitment to plexin-A1, and downregulation of R-Ras. Simultaneously, the FERM domain of FARP2 sequesters phosphatidylinositol phosphate kinase type I isoform PIPKIgamma661 from talin, thereby inhibiting its kinase activity. These activities are required for Sema3A-mediated repulsion of outgrowing axons and suppression of neuronal adhesion. We therefore conclude that FARP2 is a key molecule involved in the response of neuronal growth cones to class-3 semaphorins.  相似文献   
74.
75.
We have previously reported that immunization of the severe combined immunodeficiency (SCID) mice reconstituted with human peripheral blood mononuclear cells (PBMC) (hu-PBL-SCID mice) with inactivated human immunodeficiency virus type-1 (HIV-1)-pulsed-autologous dendritic cells (HIV-DC) elicits HIV-1-reactive CD4(+) T cells that produce an as yet to be defined novel soluble factor in vitro with anti-viral properties against CCR5 tropic (R5) HIV-1 infection. These findings led us to perform studies designed to identify the lineage of the cell that synthesizes such a factor in vivo and define the epitopes of HIV-1 protein that have specificity for the induction of such anti-viral factor. Results of our studies show that this property is a function of CD4(+) but not CD8(+) T cells. Human CD4(+) T cells were thus recovered from the HIV-DC-immunized hu-PBL-SCID mice and were re-stimulated in vitro by co-culture for 2 days with autologous adherent PBMC as antigen presenting cells, APC previously pulsed with inactivated HIV in IL-2-containing medium to expand HIV-1-reactive CD4(+) T cells. Aliquots of these re-stimulated CD4(+) T cells were then co-cultured with similar APC's that were previously pulsed with 10 microg/ml of a panel of HIV peptides for an additional 2 days, and their culture supernatants were examined for the production of both the R5 HIV-1 suppression factor and IFN-gamma. The data presented herein show that the HIV-1 primed CD4(+) T cells produced the R5 suppression factor in response to a wide variety of HIV-1 gag, env, pol, nef or vif peptides, depending on the donor of the CD4(+) T cells. Simultaneous production of human interferon (IFN)-gamma was observed in some cases. These results indicate that human CD4(+) T cells in PBMC of HIV-1 naive donors have a wide variety of HIV-1 epitope-specific CD4(+) T cell precursors that are capable of producing the R5 HIV-1 suppression factor upon DC-based vaccination with whole inactivated HIV-1.  相似文献   
76.
Traf6 is essential for murine tooth cusp morphogenesis.   总被引:5,自引:0,他引:5  
Ectodermal appendages such as skin, hair, teeth, and sweat glands are affected in patients with hypohidrotic (anhydrotic) ectodermal dysplasia (HED). It has been established that mutations in the tumor necrosis factor (TNF) superfamily of molecules, i.e., ectodysplasin (EDA), EDA receptor (EDAR), and EDAR-associated death domain (EDARADD; the intracellular adaptor for EDAR), are responsible for several forms of HED in humans and mice. We show here by in situ hybridisation that another TNF family (orphan) receptor, TROY (also known TAJ, TAJ-alpha, TRADE, and TNFRSF19), is strongly coexpressed with Edar in the epithelial enamel knot signalling centres that are believe to regulate cuspal morphogenesis during murine tooth development. Traf6 is known to function as an intracellular adaptor protein for Troy and examination of Traf6 mutant mice revealed abnormalities in molar teeth that are similar but more severe than those produced by mutations in Eda signalling molecules. This finding suggests that, in additional to ectodysplasin, another TNF pathway involving Troy/Traf6 is involved in molar tooth cusp formation and identifies an essential role for a Traf in tooth development. Developmental Dynamics 229:131-135, 2004.  相似文献   
77.
MSM/Ms is an inbred strain derived from the Japanese wild mouse, Mus musculus molossinus. It is believed that subspecies molossinus has contributed substantially to the genome constitution of common laboratory strains of mice, although the majority of their genome is derived from the west European M. m. domesticus. Information on the molossinus genome is thus essential not only for genetic studies involving molossinus but also for characterization of common laboratory strains. Here, we report the construction of an arrayed bacterial artificial chromosome (BAC) library from male MSM/Ms genomic DNA, covering approximately 1x genome equivalent. Both ends of 176,256 BAC clone inserts were sequenced, and 62,988 BAC-end sequence (BES) pairs were mapped onto the C57BL/6J genome (NCBI mouse Build 30), covering 2,228,164 kbp or 89% of the total genome. Taking advantage of the BES map data, we established a computer-based clone screening system. Comparison of the MSM/Ms and C57BL/6J sequences revealed 489,200 candidate single nucleotide polymorphisms (SNPs) in 51,137,941 bp sequenced. The overall nucleotide substitution rate was as high as 0.0096. The distribution of SNPs along the C57BL/6J genome was not uniform: The majority of the genome showed a high SNP rate, and only 5.2% of the genome showed an extremely low SNP rate (percentage identity = 0.9997); these sequences are likely derived from the molossinus genome.  相似文献   
78.
Ossification or calcification of the ligamentum flavum (LF) is relatively common in the middle and lower cervical, thoracic, and lumbar spine but extremely rare in the upper cervical region. This clinical fact suggests that there exist local factors promoting or preventing ossification or calcification of LF. However, little is known about the differences in the ultrastructure and cellular alterations of the LF between the different spinal levels, even in the cervical spine. With electron microscopy, we examined samples of LF collected surgically from the upper and lower cervical spine regions; we then studied the apoptotic appearance of ligament cells using a preferential labeling method. We found direct evidence of apoptosis of ligament cells in the LF. Apoptosis was more apparent in the upper region samples than in the lower region samples. The spaces around the normal fibroblasts were filled with thick collagen fibrils, but the collagen fibrils disappeared around the apoptotic bodies and thin fibrils were formed. The difference of the level of apoptosis may correlate to the ultrastructual difference of LF, and our data will benefit further investigations seeking to clarify the mechanism of various pathological conditions in the human LF.  相似文献   
79.
80.
We report the results of reduced-intensity unrelated cord blood transplantation (RI-UCBT) in patients with advanced malignant lymphoma. Twenty patients (median age, 46.5 years; range, 27-66 years) underwent RI-UCBT with a preparative regimen consisting of fludarabine 125 mg/m2 , melphalan 80 mg/m 2 , and 4 Gy of total body irradiation. The median infused total cell dose was 2.75 x 10(7)/kg (range, 2.3-3.4 x 10(7)/kg). Graft-versus-host disease (GVHD) prophylaxis was composed of cyclosporine or tacrolimus alone. Fifteen patients achieved primary neutrophil engraftment after a median of 20 days. Eight patients developed grade II to IV acute GVHD, and 2 developed chronic GVHD. Of the 16 patients with evaluable disease, 10 achieved a complete response. Primary disease recurred in 1 patient, and transplant-related mortality within 100 days occurred in 8 of 20 patients. The estimated 1-year probability of progression-free survival was 50%. These data suggest that RI-UCBT is a feasible option for patients with refractory lymphoma who lack an HLA-matched donor.  相似文献   
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