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排序方式: 共有955条查询结果,搜索用时 15 毫秒
1.
The hemolysin-producer coelomocytes in Holothuria polii 总被引:1,自引:0,他引:1
Calogero Canicatti Donatella Ciulla Elvira Farinalipari 《Developmental and comparative immunology》1988,12(4):729-736
Using sodium metrizoate discontinuous gradients, two hemolysin-producer amebocyte populations have been separated from total circulating Holothuria polii coelomocytes. The amebocytes of population 1 are responsible for the production of the calcium-dependent and temperature-labile hemolysin, whereas those of population 2 produce the calcium-independent and temperature-stable one. The intracytoplasmic hemolysins were evidenced also by immunofluorescence. Petaloid and filipodial amebocytes were the only positive cell types. 相似文献
2.
A. CalabrO B. Orsini S. Milani M. Psilogenis C. Surrenti 《Pharmacological research》1992,26(4):403-407
The effect of sulglycotide, a polysulphated glycopeptide isolated from pig duodenum, on PGE2, 6-ketoPGF1 alpha and TxB2 production from isolated biopsy specimens of human antral mucosa was investigated in vitro, in comparison with carbenoxolone. In addition to a tendency toward increased PGE2 production just short of statistical significance, both sulglycotide and carbenoxolone significantly increased 6-ketoPGF1 alpha accumulation in the incubation medium. TxB2 levels were not significantly modified by the two drugs. Therefore, changes in the prostanoid production by human antral mucosa could, at least partially account for the cytoprotective effects of sulglycotide in man. 相似文献
3.
Ilaria Capua Calogero Terregino Giovanni Cattoli Franco Mutinelli J.F. Rodriguez 《Avian pathology》2003,32(1):47-55
The present paper reports of the development and validation of a control strategy for avian influenza infections in poultry. The "DIVA" (Differentiating Infected from Vaccinated Animals) strategy is based on the use of an inactivated oil emulsion vaccine containing the same haemagglutinin (H) subtype as the challenge virus, but a different neuraminidase (N). The possibility of using the heterologous N subtype, to differentiate between vaccinated and naturally infected birds, was investigated through the development of an "ad hoc" serological test based on the detection of specific anti-N1 antibodies. This was achieved using a baculovirus expressing a recombinant N1 protein. The A/ck/Pakistan/H7N3 virus was used as a vaccine and birds were challenged with the HPAI A/ty/Italy/4580/V99/H7N1 strain. The homologous H group ensured a clinical protection of 93% regardless of the vaccination scheme used, and was able to prevent viraemia and muscle colonization in the clinically healthy challenged birds. However, it was not able to prevent viral shedding. The "ad hoc" serological assay was developed as an indirect immunofluorescence test, and was validated using 608 field sera, and showed an "almost perfect agreement" (Kappa value) with the HI test, with relative sensitivity and specificity values of 98.1 and 95.7, respectively. The results of the present investigation suggest that the "DIVA" control strategy may represent a tool for the control of avian influenza infections in poultry. 相似文献
4.
encapsulating structures occurred inHolothuria tubulosa. Histologically, they were formed by nodules entrapping foreign material. By an internodular mass, two or more nodules were assembled in an encapsulating body that was brown-pigmented. This pigment could be melanin, since an enzyme (i.e., phenoloxidase) responsible for its synthesis was proven. The enzyme exerted oxidase activity against dopa, dopamine and norepinephrine but not against tyrosine. The components of the sea-cucumber phenoloxidase-activating system were present in the circulating cells, which could therefore be responsible for melanin deposition during processes of foreign-body encapsulation. 相似文献
5.
6.
Substance P (neurokinin-1) and neurokinin A (neurokinin-2) receptor gene and protein expression in the healthy and inflamed human intestine 总被引:7,自引:0,他引:7 下载免费PDF全文
Renzi D Pellegrini B Tonelli F Surrenti C Calabrò A 《The American journal of pathology》2000,157(5):1511-1522
Increasing evidence suggests that tachykinins are involved in the control of pathophysiological states, such as inflammation. The precise localization of tachykinin receptors is of paramount importance in the search for their possible physiological and pathological role; in this study, therefore, we attempted to define cellular sites of substance P (NK-1R) and neurokinin A (NK-2R) receptor expression in the healthy and the inflamed human intestine by in situ hybridization and immunohistochemistry. In the normal ileum and colon, NK-1R and NK-2R were localized to smooth muscle cells of the muscularis mucosae and propria and a few inflammatory cells of the lamina propria; NK-1R expression was also found in the muscular wall of submucosal blood vessels, enteric neurons and, to a lesser degree, in surface epithelial cells. Patients with Crohn's disease and ulcerative colitis showed a dramatic increase in NK-1R density relative to controls, in both the inflamed and the uninvolved mucosa. Up-regulation of NK-1R was particularly evident on epithelial cells lining the mucosal surface and crypts, as well as on endothelial cells of capillaries and venules. Also, a marked increase in NK-2R expression was found in both groups of patients on inflammatory cells of the lamina propria, especially eosinophils. Our findings demonstrate that in the normal human intestine NK-1R and NK-2R are expressed in multiple cell types, which are endowed with different physiological functions; in addition, they demonstrate that both NK-1R and NK-2R are up-regulated in patients with Crohn's disease and ulcerative colitis. Taken together, these observations may have important physiological and pathophysiological implications, and provide the rationale for the use of NK-1R and NK-2R antagonists in the treatment of inflammatory bowel disease. 相似文献
7.
8.
Differential Expression of Matrix-Metalloproteinase-1 and -2 Genes in Normal and Fibrotic Human Liver 总被引:17,自引:9,他引:17 下载免费PDF全文
9.
Calogero Caruso Patrizia Palmeri Lorenzo Oliva Ambrogio Orlando Mario Cottone 《Tissue antigens》1985,25(1):47-49
HLA antigens were investigated in 41 Sicilian patients with ulcerative colitis and in 151 healthy controls. Frequencies of HLA-B5 and DR2 were increased in the group of patients with ulcerative colitis whereas the DR3 antigen frequency was decreased. However the corrected p values were not significant. Thus, present results indicate that in ulcerative colitis HLA linked genetic factors play a marginal role, if any. 相似文献
10.
Calogero Caruso Giuseppina Candore Diego Cigna Gabriele Di Lorenzo Guido Sireci Francesco Dieli Alfredo Salerno 《Immunologic research》1996,15(1):84-90
It is well known that aging is associated with various alterations in lymphoid cell functions, particularly with a progressive decline in immune responsiveness to exogenous antigens and increasing incidence of autoimmune phenomena. Many studies have been focused on the mechanisms of the immunologic features of aging. This review describes our results of studies performed to determine the influence of age on the capacity to produce interleukin-2 (IL-2), interferon-γ (IFN-γ), interleukin-4 (IL-4), interleukin-5 (IL-5), interleukin-6 (IL-6) and tumor necrosis factor (TNF). Mitogen-stimulated cultures of mononuclear cells (MNC) from human beings were assessed for cytokine-producing capacity. A significant decrease in IFN-γ and IL-2 production by MNC cultures from elderly individuals was observed. No significant difference was instead observed between cultures from elderly individuals and those from young ones as regards TNF-α, IL-4 and IL-6 production. Mitogen or antigen-stimulated cultures of MNC from aged mice also displayed a significant decrease in IFN-γ and IL-2 production as well as TNF-β. Instead IL-4 and IL-5 production significantly increased in these cultures. We suggest that this imbalanced cytokine production may well account for the pattern of immune response which may be observed in the elderly, i.e. a normal or increased humoral response (including autoimmune responses) in face of a low T cell immune responsiveness. 相似文献