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21.
Modulatory effect of prolactin on the resting and mitogen-induced activity of T, B, and NK lymphocytes 总被引:4,自引:0,他引:4
Lina Matera Alessandra Cesano Graziella Bellone Emanuela Oberholtzer 《Brain, behavior, and immunity》1992,6(4):409-417
Prolactin (PRL) has been shown to contribute to the development of lymphoid tissues and maintenance of physiological immune function. Here we show that the role of the hormone extends to the control of the effector phase of the immune response. In addition to triggering resting lymphocytes to cell division, the hormone can also control the magnitude of their response to polyclonal stimuli. Concentrations of PRL in the physiological range increased the [3H]thymidine, [3H]uridine, and [3H]leucine incorporation of unstimulated NK cells cultured in serum-free conditions. The same concentrations of the hormone increased the response of NK, T, and B cells to the mitogenic stimuli interleukin 2 (IL2), phytohemagglutinin (PHA), and staphylococcus aureus cowan, respectively, the effect being maximally evident in the presence of suboptimal concentrations of the mitogens. By contrast concentrations of PRL five- to tenfold the physiological levels inhibited the mitogenic response to IL2 and PHA. These data indicate a double-faceted regulatory role of this hormone in vivo. 相似文献
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Lucia Carvalho Monica Lipay Francisco Belfort Ivan Santos Joyce Andrade Alessandra Haddad Flavia Brunstein Lydia Ferreira 《Journal of plastic, reconstructive & aesthetic surgery》2006,59(9):961-968
BACKGROUND: Telomerase activity (TA) is believed to play a role in the regulation of senescence and to limit the number of cell divisions. The deregulation of telomerase appears to contribute to oncogenesis and the formation of immortal cell lines. As a result, it is believed that it could be used as a prognostic marker in melanoma. METHODS: TA was assayed by the polymerase chain reaction PCR-ELISA-based telomeric repeat amplification protocol (TRAP assay). One hundred and eight samples were distributed in four histological groups: 30 samples from primary cutaneous melanomas, 24 from peritumoural skin sites, 28 from benign melanocytic lesions, and 26 from normal skin sites as a control. RESULTS: TA was different among the four tested groups (Kruskall-Wallis test p<0.001), and increasing values of TA were observed progressing from normal skin to benign and then to malignant lesions. Among melanoma samples, there was a significant association between TA and ulceration (p=0.025), TA and vascular invasion (p=0.018) and TA and mitotic rate (p=0.029) (Mann-Whitney test). A linear regression analysis showed significant associations between the increase of TA with Breslow thickness (p=0.004) and the presence of satellites (p=0.002). CONCLUSIONS: We observed that TA had increased from control skin to peritumoural skin, and then to benign melanocytic lesions and finally to melanoma, suggesting tumour progression. TA showed higher values in the presence of some important histopathologic parameters related to poor prognosis in cutaneous melanoma such as ulceration, vascular invasion, satellites, high rates of mitosis, and in thicker tumours. 相似文献
24.
Fabricio B Teixeira 《Practical procedures & aesthetic dentistry》2006,18(3):S7-11
Several factors can contribute to the clinician's ability to achieve success in endodontic therapy. The importance of the coronal seal to positive endodontic outcomes has been established in numerous studies; fracture strength also has a significant influence on the prognosis of an endodontically treated tooth. This presentation discusses the role of these two factors in contemporary endodontic therapy and demonstrates how the utilization of an adhesively bonded, synthetic root-filling system can support the practitioner's management of nonvital teeth. 相似文献
25.
Inhibition by N-acetylcysteine of carcinogen-DNA adducts in the tracheal epithelium of rats exposed to cigarette smoke 总被引:1,自引:0,他引:1
Izzotti Alberto; Balansky Roumen; Scatolini Leonardo; Rovida Alessandra; De Flora Silvio 《Carcinogenesis》1995,16(3):669-672
The ability of the aminothiol N-acetylcysteine (NAC) to preventthe formation of carcinogen-DNA adducts in tracheal epithelialcells was investigated in Sprague-Dawley rats exposed whole-bodyto mainstream cigarette smoke for either 40 or 100 consecutivedays. 32P-Postlabelling analyses showed the occurrence of DNAadducts (12.49 adducts/108 nucleotides) after 40 days of exposure,with a trend to formation of characteristic diagonal radioactivezones. Total adduct levels were not further enhanced after 100days of exposure to smoke, although significant changes occurredin the amounts of individual adducts. NAC, given by gavage inthe 40 day study and in drinking water in the 100 day study,significantly inhibited the formation of smoke-related carcinogen-DNAadducts in the tracheal epithelium, to such an extent that adductlevels were not significantly higher than those detected insham-exposed control rats. Together with a variety of othermolecular, clastogenicity, metabolic, cytological and histopathologicalend-points investigated in rodents and with the preliminaryevidence arising from a study in humans, these results documentthe considerable efficacy of oral NAC in inhibiting smoke-relatedcarcinogen-DNA adducts. 相似文献
26.
Pierpaolo Sileri Vito Maria Stolfi Giampiero Palmieri Alessandra Mele Alessandro Falchetti Sara Di Carlo Achille Lucio Gaspari 《Journal of gastrointestinal surgery》2007,11(12):1662-1668
Stapled hemorrhoidopexy is widely accepted to treat hemorrhoids, but serious complications have been reported. In this prospective
audit, we correlated clinical outcome with pathological findings. From January 2003 to April 2007, 94 patients underwent hemorrhoidopexy.
Macroscopic appearance of the specimen (shape, size, and depth) was recorded. Microscopically, the presence of columnar, transitional,
and squamous epithelium, the involvement of circular/longitudinal smooth muscle, and features of mucosal prolapse were assessed.
Clinical outcome was evaluated by a validated questionnaire. Postoperative pain, secretion, and bleeding durations were 12.7 +/− 10.6,
5.6 +/− 9.6, and 6.3 +/− 8.4 days. Patient’s return to work averaged 16.7 +/− 10.7 days. Fissure, skin tags, and anal strictures
were observed in 23.4%. Seven patients experienced pain for a significantly longer period of time. All specimens contained
columnar mucosa, but 29.8% contained columnar and transitional epithelium and 12.8% contained columnar, anal transitional,
and stratified squamous epithelium. Smooth muscle was observed in 62.7%. Pain was significantly increased if transitional
epithelium was present in the specimen. No correlation or differences were observed if smooth muscle was present, although
postoperative bleeding was more frequent. Hemorrhoidopexy is safe and effective. The specimen should always be sent for pathology
examination. Only columnar epithelium should be present and, although the presence of smooth muscle does not influence the
outcome in terms of functional results, its presence may play a role in postoperative bleeding.
Presented as poster at the Digestive Disease Week, May 2007, Washington, USA 相似文献
27.
Luzitano Brando Ferreira Celso Teixeira Mendes Cludia Emília Vieira Wiezel Marcelo Rizzatti Luizon Aguinaldo Luiz Simes 《American journal of human biology》2006,18(5):702-705
Allelic frequencies of eight autosomal short‐tandem repeat (STR) loci (TH01, TPOx, CSF1PO, vWA, FES/FPS, F13A1, F13B, and CD4) were determined in 400 individuals born in the State of São Paulo. No significant deviations from Hardy‐Weinberg equilibrium were found in any loci analyzed. The Unweighted Pair‐Group Method with Arithmetic Mean (UPGMA) tree constructed based on genetic distances revealed that the present population was grouped with Europeans, and separated from African and Amerindian populations. Estimates of admixture components based on the gene identity method revealed 79% European, 14% African, and 7% Amerindian contributions to this Brazilian population sample. Am. J. Hum. Biol. 18:702–705, 2006. © 2006 Wiley‐Liss, Inc. 相似文献
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30.
F. Teixeira Brandt C. D. Costa Albuquerque J. W. Barros Leal 《International urogynecology journal》1997,8(6):332-335
We report on the vaginal mucosal folds (VMF) at the urethral external meatus. Resection of the VMF reduces the dispersed micturition
and other urinary symptoms.
EDITORIAL COMMENT: The investigators describe the presence of a vaginal mucosal fold (VMF) just dorsal to the urethral meatus
and its relationship to voiding abnormalities. VMF were found on physical examination in 8.9% of the clinic population, all
of whom complained of dispersed micturition, and 79% also experienced other voiding abnormalities. The complaint of dispersed
micturition was successfully treated with excision of the VMF, and the other associated symptoms were improved. This structure
should be routinely looked for on physical examination, especially in patients with voiding symptoms. Only further investigation
of this newly described entity at other centers around the world will determine the incidence of the anatomic finding and
the prevalence of associated voiding disturbances across different populations. 相似文献