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Progress in understanding carcinogenesis has shown cancer to be a disease caused by gene abnormalities, and a variety of oncogenes and tumor suppressor genes have thus been identified. Advances in molecular biology have given us new tools for diagnosing, staging and predicting the outcome for cancer patients and gene therapy could therefore potentially revolutionize the treatment of gastrointestinal (GI) tract cancer. Progress has been made in several approaches related to genetic modification: (1) antisense oncogene and the restoration of tumor suppresor gene therapy; (2) suicide gene therapy; and (3) cancer immunotherapy. In situ in vivo gene transfer is a practical method of gene therapy for GI tract cancer. Although many hurdles need to be overcome to achieve effective gene transfer and targeting, our early results of in situ in vivo suicide gene therapy for canine gastric cancer are promising. The era of combined treatment consisting of surgery and molecular surgery for GI tract cancer is thus considered to soon be possible.  相似文献   
3.
The ascidian tadpole larva represents the basic body plan of all chordates in a relatively small number of cells and tissue types. Although it had been considered that ascidians develop largely in a determinative way, whereas vertebrates develop in an inductive way, recent studies at the molecular and cellular levels have uncovered several similarities in the way developmental fates are specified. In this review, we describe ascidian embryogenesis and its cell lineages, introduce several characteristics of ascidian embryos, describe recent advances in understanding of the mechanisms of cell fate specification, and discuss them in the context of what is known in vertebrates and other organisms. Developmental Dynamics 236:1748–1757, 2007. © 2007 Wiley‐Liss, Inc.  相似文献   
4.
T Matsukura  T Iwasaki  M Kawashima 《Virology》1992,190(1):561-564
In a plantar cyst composed of the wall of the squamous cell layer and the horny inner substance in the lower dermis, we found characteristic pathological changes, such as cytoplasmic eosinophilic inclusions and vacuolated structure, and, immunohistochemically, the papillomavirus capsid antigen. The human papillomavirus (HPV) DNA cloned from the cyst showed no homology with other known prototypes of HPV (HPV 1 through HPV 59) by Southern blot analysis under stringent conditions and was named as HPV 60. HPV 60 DNA was found in three other cases of plantar cyst with the identical pathological changes, but not in a plantar cyst without such changes. The results suggest that HPV 60 has unique biological properties to induce a plantar cyst as a distinct type of cutaneous HPV.  相似文献   
5.
A patient presenting with osteomyelitis of the pelvis is described. In this case it was difficult to establish a correct diagnosis by use of scintigraphic scanning, in spite of clear roentgenographic evidence of osteomyelitis.  相似文献   
6.
Seven human gastric cancer xenografts with different concentrations of EGF receptor were established in nude mice. The expression of EGF receptor in the tumors was demonstrated by Western blotting with anti-EGF receptor antibody, binding assay with 125I-EGF and immunohistochemistry with anti-EGF receptor antibody. Western blotting revealed EGF receptor doublet bands at molecular masses of 150 KDa and 170 KDa in all of the samples. The concentration of 125I-EGF binding activity in the tumors ranged from 36.0 to 11,000 fmol/mg protein, with a mean of 345 fmol/mg protein. EGF receptor was also demonstrated immunohistochemically on the apical border of the glands and the cell membrane of the tumor cells. There seemed to be a close correlation between the concentration of 125I-EGF binding activity and the doubling time of these tumors in nude mice (gamma = -0.68). However, no definite correlation was observed between EGF ligand binding and histological features of intestinal type or diffuse type. The expression of EGF receptor appears to facilitate the growth of human gastric cancer xenografts in nude mice.  相似文献   
7.
The characteristics of influenza-associated encephalopathy is the high mortality and nimble progress with coma which appears in general cases within 48 hours. Most of patients show no abnormalities in the standard blood checks on admission or in early stage. In this study we investigated if a rapid assay of interleukin (IL)-6 is useful in influenza-associated encephalopathy in early stages. The levels of IL-6 in patients with influenza-associated encephalopathy did not show any significant difference compared with those in patients with febrile convulsion and rotavirus-associated convulsion. However the levels of IL-6 in severe cases were significantly higher than those of mild cases with influenza-associated encephalopathy. Consequently the rapid assay of serum IL-6 is useful to evaluate and decide the therapies.  相似文献   
8.
The differences reported by various authors in regard to the inhibitory effect of the same antimitotic product on the production of antibodies, may be attributable in particular to the antigen used and to the technique of administration of the product. These differences have made it necessary to work out a test that is not subject to criticism in these respects.

After an investigation of the cytological reactions provoked in the mouse by various antigens, the authors have singled out three of these antigens: human albumin, the poliomyelitis virus and an allogeneic skin graft. The hyperbasophilic cells which are predominantly present in the lymphoid centres are, respectively, lymphocytes for the first, plasmocytes for the second and histiocytes for the third of these antigens.

In view of the different mechanisms of action that are possible with the different antimitotic products the authors used three methods of administration: entirely `before' the antigenic stimulus; total dose administered entirely `after' the antigenic stimulus; total dose administered partially `before' and partially `after' the antigenic stimulus.

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9.
Using cDNA microarray technology, the expression of chemokine genes in the elicitation site of 2,4,6-trinitrochlorobenzene-induced contact hypersensitivity (CHS) was examined in mice. Of the 33 genes analyzed, levels of 11 gene expressions changed, and these can be assigned to four groups based on their kinetic patterns; (1) LARC/CCL20 whose mRNA level increased rapidly at 3 h post-challenge and then gradually decreased, (2) JE/CCL2, MARC/CCL7, MIP-1gamma/CCL9, monocyte chemoattractant protein (MCP)-5/CCL12, ELC/CCL19 and BRAK/CXCL14 whose mRNA levels increased with time and reached the maximum at 6-9 h post-challenge, (3) LIX/CXCL5, Mig/CXCL9 and IP-10/CXCL10 whose mRNA levels increased gradually at least up to 12 h post challenge, and (4) SLC/CCL21 whose mRNA level decreased gradually with time after challenge. The findings suggest that sequential expression of chemokine genes is essential for orientating non-specific skin response to hapten-specific CHS response through the recruitment of inflammatory cells such as neutrophils, monocytes/macrophages and T-cells from the circulation into the tissue site.  相似文献   
10.
Nuclear beta-catenin plays crucial roles in the establishment of the embryonic axis and formation of mesendoderm tissues in ascidians and other animals. However, the cue responsible for nuclear accumulation of beta-catenin in the vegetal hemisphere is still unknown in ascidians. Here, we investigated the roles of Wnt5alpha and Dsh in the nuclear accumulation of beta-catenin and activation of its downstream genes in the ascidian Halocynthia roretzi. Wnt5alpha knockdown embryos lost nuclear accumulation of beta-catenin at the 64-cell stage but not at the 32-cell stage, and expression of Hr-lim, one of the targets of beta-catenin, was impaired in the anterior region of the embryo. Zygotic Wnt5alpha expression in the anterior-vegetal blastomeres was primarily responsible for these defects. Dsh knockdown showed no effect on nuclear localization of beta-catenin, but inhibited Hr-lim expression in the posterior region. These results suggest that maintenance of nuclear Hr-beta-catenin after the 64-cell stage is regulated by zygotic Hr-Wnt5alpha, and that expression of its target genes is modulated by both Hr-Wnt5alpha and Hr-Dsh. Our results also highlight the importance of nuclear accumulation of beta-catenin up to the 32-cell stage through a still unclarified mechanism.  相似文献   
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