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Basophils are the main cell component in cutaneous basophil hypersensitivity (CBH) reactions, but the role of basophils and the factors which gather them into CBH reaction sites are unknown. To investigate these problems, we induced CBH reactions in guinea pigs and observed basophils and mast cells in the skin reaction sites using light and electron microscopy. Basophils infiltrated into CBH reaction site appeared at 5 h after the challenge with antigen, increased till 48 h and decreased thereafter. On the other hand, the number of mast cells and their granules decreased after the challenge with antigen and reached a minimum at 48 h, but recovered at 96 h. The changes in the number of basophils and mast cells were complementary. This result suggested that the granules of mast cells may have a factor to gather basophils into the CBH skin reaction site. Furthermore, basophils infiltrated in the CBH reaction site were degranulated by the rechallenge with antigen, which was considered to be by an anaphylactic reaction.  相似文献   
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Telomerase is an enzyme required by actively dividing cells to maintain the ends of chromosomes (telomeres). It is present in germline tissue, stem cells and cancer cells, but is repressed in somatic cells. Efforts are underway to exploit this selective expression of telomerase in cancer therapeutics. This review describes the status of telomerase research, which although at present predominantly preclinical, has the potential to enter clinical research.  相似文献   
4.
Soda T  Hori D  Onishi H  Miyakawa M 《Urology》1999,53(6):1228
A case of granulomatous nephritis after intrarenal bacille Calmette-Guérin (BCG) therapy is reported. High fever greater than 38.5 degrees C lasted for 1 month, without response to conservative therapy. Standard nephroureterectomy was subsequently carried out. Histopathologic findings from the surgical specimen were compatible with BCG-induced granulomatous nephritis. The use of a syringe pump for retrograde instillation of BCG was thought to be the major cause of this severe complication.  相似文献   
5.
OBJECTIVE: To describe epidemiological features of HIV prevalence among female commercial sex workers (CSWs) in Cambodia, a cross-sectional study using a questionnaire study and serological tests was carried out from December 1997 to January 1998. We report the main results of the analyses of serological tests in this article. METHODS: Two hundred ninety six CSWs working in Sisophon and Poi Pet, located in northwest Cambodia, Bantey Mean Chey province, were recruited for interview based on a questionnaire on sexual behavior, and serological tests. The blood samples were examined for HIV antibody, Chlamydia trachomatis IgG antibody, TPHA, Hepatitis B surface antigen, and Hepatitis B surface antibody. The relationship between HIV and the other STD's was analyzed by using logistic regression analysis. RESULTS: The HIV seroprevalence rate was 43.9% (130 out of 296). The seropositive rate of Chlamydia trachomatis IgG antibody (C.T.-IgG-Ab) was 73.3% (217 out of 296). Logistic regression analysis showed a significant association between C.T.-IgG-Ab positive and HIV prevalence. (Odds Ratio: 5.33; 95% Confidence Interval, 2.82-10.07). CONCLUSIONS: This study suggests that the existence of Chlamydia trachomatis is closely related with HIV prevalence among CSWs in Cambodia. Other STDs may also increase susceptibility to male-to-female sexual transmission of HIV. This suggests that appropriate prevention against STDs will be needed for the control of HIV prevalence in Cambodia.  相似文献   
6.
A huge phyllodes tumor of the breast that appeared grossly malignant in a 43-year-old woman is described. The patient suffered from a large breast tumor that suddenly increased in size over 5 months to occupy the entire breast. The tumor was hard, ulcerated and 20 cm in greatest diameter. Diagnostic imaging (US, CT and MRI) demonstrated a circumscribed mass with a large cystic cavity. She underwent total mastectomy under a diagnosis of malignant breast tumor. Grossly, the cut surface of the tumor showed a large cystic cavity surrounding a fleshy, hemorrhagic and necrotic mass with a lobulared or trabeculared appearance. Unexpectedly, benign phyllodes tumor (PT) without any stromal overgrowth was diagnosed histologically. She has been doing well since total mastectomy. In our case and in many other reported cases, PT does not show any distinctive correlation between pathologic findings and tumor behavior. Thus wide local excision is the preferred initial treatment for PT.  相似文献   
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Background: Telomerase is an important enzyme whose activity has been convincingly demonstrated in humans recently. It is required for maintenance of ends of chromosomes (telomeres) during cell division. Since its presence has been selectively demonstrated in dividing cells including tumor cells, it has generated considerable excitement as a potential anti-cancer strategy.Design: In this article, we review the current relevant biology of the enzyme, the challenges encountered in the preclinical phase of target development and the current efforts that focus on telomeres and telomerase as therapeutic targets. We also speculate on the potential toxicities and mechanisms of resistance that may be encountered during use of such therapies.  相似文献   
9.
We used an automated peptide synthesizer to produce a peptide, metalloselenonein, that contains selenocysteine residues substituted for all cysteine residues in Neurospora crassa copper metallothionein. Metalloselenonein binds 3 mol of Cu(I) per mol. This adduct shows a broad absorption band between 230 and 400 nm and a fluorescence band at 395 nm, which can be attributed to copper-selenolate coordination. The circular dichroism spectrum of the copper-metalloselenonein complex shows a positive band around 245 nm attributable to asymmetry in metal coordination.  相似文献   
10.
H. Soda    K. Kuriyama    M. Tomonaga    E. Yao    T. Amenomori    Y. Yoshida    T. Matsuo    I. Jinnai    N. Sadamori  M. Ichimaru 《British journal of haematology》1985,59(4):671-679
A case of Philadelphia (Ph1) chromosome negative chronic myeloid leukaemia (CML) developed lymphoid crisis. Immunological marker studies disclosed that the lymphoid cells were sheep erythrocyte-rosetting-, Leu-1+, Leu-5+, OKT-4+, OKT-8+, common ALL antigen-, HLA-DR-, cytoplasmic and surface immunoglobulin-, MAS 036C(antithymocyte)+ (after in vitro culture) and terminal deoxynucleotidyl transferase-, indicating T-cell phenotypes, probably of common thymocytes. Cytochemical staining also demonstrated immature T-cell characters: dot-positivity for acid phosphatase and beta-glucuronidase, and negative for acid alpha-naphthyl acetate esterase. All bone marrow metaphases exhibited normal karyotypes. Our observation suggests that the neoplastic features of a common stem cell for myeloid and lymphoid cell lines are very similar in Ph1 positive and negative CMLs, and that the stem cell can differentiate towards T-lineage.  相似文献   
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