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41.
AIMS: The high incidence of clinically diagnosed prostatic cancer is exceeded by the frequency of tumours detected at autopsy. The Ets-1 proto-oncogene is expressed by a variety of malignant and normal tissues. Therefore, in this study, expression of Ets-1 protein was investigated in 'latent' prostatic cancer detected at autopsy, compared with benign prostatic hyperplasia, normal prostatic tissues and clinical prostatic cancer. METHODS AND RESULTS: Using immunohistochemistry, we analysed Ets-1 expression in 95 prostatic specimens including 19 cases of latent prostatic carcinoma (LPC) and 55 cases of clinical prostatic carcinoma (CPC), 11 cases of benign prostatic hyperplasia (BPH) and 10 cases of normal prostate (NP). Differences in the incidence of LPC and CPC suggest different courses for the biological progression of prostatic cancer. There was a significant difference in the degree of Ets-1 expression in CPC and LPC (P < 0.05). Ets-1 was not expressed in BPH and NP, but in malignant cases (57 of 74; 77.0%) commonly demonstrated immunoreactivity in the tumour cells. In our study the expression of Ets-1 between benign and malignant, and well, moderately and poorly differentiated adenocarcinomas of prostatic cancer showed significant differences. The presence of Ets-1 mRNA was confirmed by in-situ hybridization in human prostatic tissues. CONCLUSION: Our results suggest that Ets-1 might play an important role in carcinogenesis and/or the progression of human prostatic carcinomas.  相似文献   
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Five anti-human deoxyribonuclease I (DNase I) monoclonal antibodies were obtained from BALB/c mice immunized with DNase I purified from human urine. Four of them inhibited DNase I enzyme activity, as did a rabbit polyclonal antibody; these 4 did not have immunostaining ability. The remaining one had immunostaining ability but no inhibitory activity. A Sepharose 4B column conjugated with 1 of the 4 antibodies that had inhibitory activity effectively adsorbed and eluted the DNase I enzyme; this did not occur with the rabbit polyclonal antibody. We showed that adding an immunoaffinity chromatography step made the purification of human DNase I easier and faster than the conventional procedure.  相似文献   
44.
An autopsy case of pulmonary candidiasis occurring in a neonatal girl was reported. The mycological examination of the lung taken at autopsy revealed only Candida albicans and followed by the elucidation under the microscopic sections prepared with special stains; periodic acid-Schiff and methenamine silver, in the lung, stomach, umbilical cord, and amnion. The presence of Candida vaginitis in her mother supported the concept that Candida albicans was the etiological agent of the pulmonary candidiasis.  相似文献   
45.
Alveolar macrophages (AM) from normal rats had immunosuppressive activity to mitogen-induced proliferative responses of splenic lymphocytes. We studied the mechanism and the implication of the nitric oxide synthetase pathway in AM-mediated suppression of concanavalin A (Con A)-induced lymphocyte proliferation. The culture supernatant from AM cultures alone did not have immunosuppressive activity to Con A-induced proliferative responses of non-adherent spleen cells (n-ad SC), but the culture supernatant from co-culture of AM and autologous n-ad SC had this activity. Con A-pulsed AM also liberated the immunosuppressive factor. When AM and autologous n-ad SC were cultured separately under the condition that medium could freely communicate, the culture supernatant did not suppress the Con A-induced proliferative response of n-ad SC. This indicated that the immunosuppressive factor was liberated when AM was activated by cell-to-cell contact with n-ad SC. Further, we examined the immunosuppressive activity of the culture supernatant of co-culture of AM and autologous n-ad SC to Con A-induced responses of allogeneic n-ad SC and xenogeneic murine n-ad SC, and allogeneic mixed leucocyte reaction, and found that this culture supernatant could suppress all these proliferative responses. Nitrate (NO2-) synthesis was markedly augmented in the culture supernatants of Con A-pulsed AM and co-culture of AM and n-ad SC. NG-monomethyl-L-arginine (MMA), a specific competitive inhibitor of the nitric oxide synthetase pathway (NOSP), extinguished both NO2- synthesis by AM and AM-mediated immunosuppressive activity. These data suggest that NOSP was important in AM-mediated suppression of Con A-induced lymphocyte proliferation.  相似文献   
46.
47.
A simple membrane immunoassay assay system, Quik Pack, for the detection of hepatitis C virus antibody was compared with two enzyme-linked immunosorbent assays (ELISAs) in a study of 600 serum samples. Quik Pack exhibited excellent sensitivity and specificity: 96.0 and 99.7%, respectively, versus the ELISA-2 and 99.7 and 99.4%, respectively, versus the ELISA-3.  相似文献   
48.
Mammalian cells that have been committed to a certain cell lineage cannot be directed to other lineages. However, some astrocytes in the mammalian brains have been reported to represent plasticity to redirect to other cell lineages. We found that mouse hippocampal astrocytes cultured in aggregate forms of "astrosphere", redirected to MAP2-positive immature neurons. In astrospheres, basic HLH factors positively regulating neuronal differentiation were up-regulated and Id3 inhibiting basic HLH factors was down-regulated. Ectopic Id3 induction repressed redirection of astrocytes to a neuronal lineage, suggesting that astrosphere formation induced plasticity of astrocytes by changing the gene expression patterns.  相似文献   
49.
OBJECTIVE: To describe the prevalence of crack cocaine use in an HIV-infected population and to examine the association between crack use after HIV diagnosis and high-risk sexual behaviors for heterosexual men, heterosexual women, and men who have sex with men (MSM). METHODS: Analysis of cross-sectional interviews conducted from January 1995 through December 1998 with HIV infected adults in 12 states. RESULTS: Of 10,415 persons with HIV or AIDS, 66.6% never used crack, 10.7% used crack before HIV diagnosis but not after, and 22.7% used crack after diagnosis. High-risk sexual behaviors were more prevalent among those who had ever used crack and were most prevalent among those who used crack after diagnosis. In multivariable analyses, crack use after diagnosis was associated with having multiple sex partners and trading sex for drugs/money in all three groups: heterosexual men, heterosexual women, and MSM. For heterosexual women and MSM, crack use after diagnosis was associated with unprotected sex with a main partner, and among heterosexual men and MSM, with unprotected sex with casual partners. CONCLUSIONS: Crack use after HIV diagnosis was associated with high-risk sexual behaviors. Treatment programs to assist people in quitting crack are needed to help reduce the risk of HIV transmission from this population.  相似文献   
50.
I Nakashima  N Kato 《Immunology》1975,29(4):643-652
In mice primed with a mixture of bovine serum albumin (BSA) and adjuvant (capsular polysaccharide of Klebsiella pneumoniae (CPS-K)) cell-associated immunological memory was increased secondarily after a second injection of BSA alone, whereas a primary injection of BSA alone into normal unprimed mice did not result in detectable memory. The optimum antigen doses for expression of the primary and secondary memories of adoptively transferred cells from unboosted primed donors or boosted donors in in vivo culture systems were very similar, although those observed in intact mice were very different, as reported previously. The size of the secondary memory of adoptively transferred cells from boosted donors was more than ten times greater than that of the primary memory of adoptively transferred cells from unboosted primed donors. The lag period for increase of the secondary memory was shorter than that for the primary memory. Both primary and secondary memories increased during a long period (up to 3 months) after the antigenic stimulus. From the results of this study it was concluded that cell-associated immunological memory could be amplified in a secondary fashion upon contact with a second stimulus.  相似文献   
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