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991.
992.
PURPOSE: Chlamydia psittaci (Cp) has been associated to ocular adnexal lymphomas (OAL) with variable geographic distribution. Herein, we used multiple Chlamydia detection tools to identify Cp elementary bodies-containing cell and to assess Cp prevalence in both nodal and extranodal lymphomas. EXPERIMENTAL DESIGN: TETR-PCR, immunohistochemistry, immunofluorescence, electron microscopy, and laser-capture microdissection were done in 35 OALs to define their effect in Chlamydia detection and, moreover, to identify the Cp cellular carrier. Cp prevalence was screened by TETR-PCR in 205 extraorbital lymphomas and 135 nonneoplastic controls. RESULTS: Twenty-six (74%) OALs were associated with Cp infection: immunohistochemistry, immunofluorescence, and laser-capture microdissection-assisted PCR showed that monocytes/macrophages were the Cp carriers; electron microscopy showed the presence of intact Cp elementary bodies into these cells. Immunohistochemistry and TETR-PCR showed a 70% concordance rate (P = 0.001). Cp DNA was equally prevalent in non-OAL, nodal, and extranodal lymphomas: among the latter, it was more common in diffuse large B-cell lymphomas of the skin (P = 0.03) and Waldeyer's ring. CONCLUSIONS: This multiparametric approach shows, for the first time, that monocytes/macrophages are the carriers of Cp, Cp seems preferentially associated with lymphomas arising in organs primarily exposed to antigens. The clinical implications of these findings deserve to be prospectively investigated.  相似文献   
993.
Two ketolides, telithromycin and HMR 3004, were evaluated for their in vitro activity against erythromycin-susceptible and -resistant strains of Streptococcus pyogenes and Streptococcus pneumoniae. On the basis of their resistance to macrolide, lincosamide and streptogramin (MLS) antibiotics, erythromycin-resistant test strains were assigned to the constitutive resistance (cMLS) phenotype, the inducible resistance (iMLS) phenotype or the M phenotype. iMLS S. pyogenes strains were further subdivided into the three recently described subtypes iMLS-A, -B and -C. Telithromycin and HMR 3004 were uniformly and highly active against pneumococci (regardless of their susceptibility or resistance to erythromycin and/or penicillin), erythromycin-susceptible S. pyogenes and erythromycin-resistant S. pyogenes strains of the M phenotype (in which resistance is mediated by an efflux system) or iMLS-B or -C phenotype (in which resistance is mediated by a methylase encoded by the ermTR gene). Both ketolides were less active against erythromycin-resistant S. pyogenes strains with the cMLS phenotype or the iMLS-A subtype (where resistance is mediated by a methylase encoded by the ermAM gene), these strains ranging in phenotype from the upper limits of susceptibility to low-level resistant.  相似文献   
994.
The quantity variations of glycosaminoglycans (GAGS) in urothelial samples from patients with malformations presenting infectious, obstructive or lithiasis signs have been investigated. They showed a highly significant deficiency in GAGS in patients with recurrent infections of the urinary ways, a more limited deficiency in sufferers from lithiasis and values within the normal range in patients with obstructive malformations.  相似文献   
995.
996.
The Authors report the results based on 20 years of practice on obstetric psycho-prophylaxis (PPO). Data on presence at course, on frequency, on primipares/pluripares ratio, on labour, on timing and mode of delivery, are assembled. Moreover, neonatal status at birth and at 10th day of life, are investigated. The data obtained were compared with a control group, constituted by women without any treatment before delivery. The acquired experience confirm the utility of PPO in the ordinary clinical practice.  相似文献   
997.
It has been shown that a marked increase in the levels of Rlα sub-units and a decrease in RIIβ sub-unit levels correlate with neoplastic transformation or with the mitogenic response of normal cells to hormones and growth factors. The selective down-regulation of RIα and the following induction of RIIβ determine cell-growth arrest and differentiation of several cancer cells. To directly address the question whether the 2 protein-kinase-A(PKA) isoforms play different roles in the control of proliferation and cell-cycle distribution, we introduced and over-expressed the different PKA sub-units in Chinese-hamster-ovary (CHO) cells via retroviral-vector-mediated gene transfer. Whereas CHO cells treated with RIα anti-sense oligodeoxynucleotides were growth arrested and accumulated in the G0/G1 phases of the cell cycle, infection of CHO cells with a retroviral vector in order to over-express RIα determined growth advantages in monolayer conditions and substantially increased their cloning efficiency in soft agar. These events correlated with a sustained percentage of cells in S phase induced by RIα over-expression in the infected cells. In contrast, CHO cells infected with retroviral vectors over-expressing either a RIIβ sub-unit or a Cα catalytic sub-unit of PKA exhibited growth arrest within a few days of culture and accumulated in the G2-M phase of the cell cycle. The results of our study demonstrate that the different PKA sub-units play different and specific roles in the control of cell growth and cell-cycle distribution.  相似文献   
998.
Antigen 90K is produced by several tumor-cell lines and by patients with cancer. Its function has not yet been clarified, although recent reports suggest that it plays a role in the tumor—host relationship—for example by stimulation of natural killer and lymphokine-activated killer-cell activity. Previous studies have indicated that 90K expression may be under the influence of interferon-α. Here, we provide evidence that both interferon-α and -γ can enhance the secretion of 90K and augment the level of specific mRNA expression in 3 ovarian carcinoma cell lines (OVCAR-3, HTB-77 and SKOV-6). However, interferon-γ leads to depletion of cellular 90K whereas interferon-α increases both secreted and cellular 90K levels. In equimolar concentrations, Interferon-α was always superior to interferon-γ in augmenting 90K protein or mRNA levels. Combinations of TNF with interferon-γ were highly synergistic both in reducing cell proliferation and in increasing 90K secretion and mRNA expression. This synergism was seen to a lesser extent with interferon-α.  相似文献   
999.
Eight families with two or more first-degree relatives affected with ovarian carcinoma were identified among a series of 138 consecutive ovarian cancer patients. History of breast cancer was reported in six of the eight families. Five of 19 patients with familial cancer developed ovarian cancer as a second primary tumor following breast carcinoma, whereas only 6/130 sporadic cases had a previous history of breast cancer. No significant difference was detected in clinical and pathological features between sporadic and familial cases. However, in three high-risk families ovarian cancer tended to develop at a younger age compared with other familial cases and with sporadic occurrences, and nulliparity was less frequent in the familial group. These observations emphasize the need to take into account multiple factors-in addition to positive family history-for the evaluation of genetic predisposition to ovarian carcinoma.  相似文献   
1000.
From 1977 to 1987, 45 patients with FIGO stage I endometrial adenocarcinoma with high-risk attributes and disease confined to the pelvis were prospectively treated with postoperative pelvic radiation. By study design, all patients underwent staging laparotomy with pelvic and paraaortic lymphadenectomy. All patients had either grade 1 or 2 adenocarcinoma and greater than 50% myometrial invasion or grade 3 adenocarcinoma with less than or greater than 50% myometrial invasion. The estimated 5-year survival for all 45 patients was 77% and the 5-year disease-free interval was 82%. Regional control was achieved in 89% of all patients, with 4% recurring at distant sites. When patients were stratified according to surgical-pathologic findings, 33 patients with disease confined to the uterus or uterus and pelvic nodes (surgical stage I) had estimated 5-year survival and disease-free interval of 88%. Of these 33 patients, 10 with grade 1 or 2 adenocarcinoma and deep myometrial invasion had 5-year disease-free intervals of 100%, while 23 patients with grade 3 adenocarcinoma with less than or greater than 50% myometrial invasion had disease-free intervals of 79 and 91%, respectively. From these results, it was concluded that patients with high-risk attributes demonstrated to have disease confined to the uterus or uterus and pelvic nodes can achieve excellent survival following surgical staging and postoperative pelvic radiation.  相似文献   
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