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11.
Leon Ardekian Efrat Oved-Peleg Eli E Mactei Micha Peled 《Journal of oral and maxillofacial surgery》2006,64(2):277-282
PURPOSE: Augmentation of the maxillary sinus floor is a well-documented technique and is generally accepted as a pure implantology procedure to facilitate placement of dental implants in the posterior atrophic maxilla. The objective of this report was to evaluate the significance of the sinus membrane perforations on the incidence, complications, and success rate of this procedure. PATIENTS AND METHODS: Patients who received sinus floor augmentation and simultaneous placement of dental implant were included in this study. Subgroup I consisted of patients who had their sinus membrane perforated and repaired during the procedure with resorbable membrane. Subgroup II consisted of patients whose Schneiderian membrane was not perforated during the procedure. The patients were followed between 1 to 4 years after augmentation. RESULTS: All perforations were classified as class II or III. The success rate of the implants in the perforation group was 94.4%, and that for the nonperforation group was 93.9%. The difference between the 2 study groups was statistically not significant. A significant statistical correlation was found between the residual ridge height and the membrane perforation (P < .01). CONCLUSIONS: Mainly due to technical difficulties, maxillary sinus membrane perforation occurs more frequently with a small height of residual alveolar bone. In this study, no statistical difference was observed in the success rate of the immediate implants placed with sinus bone grafting in patients whose membrane was perforated versus those patients in whom an intact membrane was maintained. 相似文献
12.
Limited efficacy of chemotherapy in most solid tumors has revived interest in immunotherapeutic approaches for cancer. One novel form of immunotherapy is the use of cancer vaccines consisting of tumor cells genetically engineered to secrete cytokines. The rationale for this immunization strategy is based on the existence of tumor-specific antigens, on the importance of the cellular arm of the immune system in mediating an effective antitumor response, and on the role of cytokines in regulating the cellular immune response. Such tumor vaccines showed considerable promise in various animal models and induced potent antitumor immunity in the host, which led to regression of established tumors and, moreover, produced immunological memory protecting animals from a subsequent tumor challenge at a distant site. Translated to the human patient, this implies that genetically modified tumor vaccines may be able to eradicate or reduce existing tumor deposits to subclinical levels as well as provide long-term protection from regrowth of tumor cells. This report will review and discuss the concept and rationale for the use of cytokine-secreting tumor vaccines for the treatment of human malignancies. 相似文献
13.
14.
The effect of the proton pump inhibitor omeprazole on the anticoagulation and the pharmacokinetics of warfarin enantiomers was studied in rats. Omeprazole given intraperitoneally in a daily dose of 0.67 mg/kg over 8 days had no significant effect on the absorption, distribution and the total serum clearance values of the S- and R-enantiomers of warfarin. Omeprazole did not affect the pre-treatment baseline blood coagulation and the in vitro rat serum protein binding of warfarin enantiomers. In vitro study with rat liver microsomes showed that omeprazole had an inhibitory effect on the hydroxylation of warfarin enantiomers. Results obtained from in vivo urinary excretion study revealed that omeprazole inhibited the formation clearance of both S- and R-form oxidative metabolites, but increased that of the overall reductive metabolites, and the renal clearance of S- and R-enantiomers, of warfarin. As a consequence, the total serum clearance values for warfarin enantiomers remained unchanged and the hypoprothrombinaemic response produced by warfarin was not affected. 相似文献
15.
Prodrugs of -estradiol (1) were prepared with the objective of improving its oral bioavailability. -Estradiol-3-acetylsalicylate (2), -estradiol-3-salicylate (3), and -estradiol-3-anthranilate (4) were synthesized. With these prodrugs the 3-phenolic hydroxy group of estradiol was protected, so that first-pass conjugative metabolism could be reduced. Prodrug hydrolysis rates in dog and human plasma in vitro were determined. Deacetylation of estradiol-3-acetylsalicylate was much more rapid than its hydrolysis to estradiol. In dogs, oral estradiol bioavailability after administration of 2 and 4 was 17-fold and 5-fold higher, respectively, than after oral 1. 相似文献
16.
Naltrexone-3-salicylate (3), a prodrug of naltrexone (1), was prepared by a simple procedure from naltrexone-3-acetylsalicylate (2). The plasma (dog and human) hydrolysis half-life of 3 was found to be approximately 30 min. Compound 2 was previously shown to hydrolyze in dog and human plasma with a fast deacetylation step to 3, followed by slower hydrolysis of 3 to 1 (t
1/2, 30 min). Oral naltrexone bioavailability was greatly improved (30-fold) after oral administration of 3 to dogs, similar to the improvement observed after oral administration of 2. The half-life of naltrexone in dogs after oral administration of 3 was similar to that observed after oral administration of 2 (1 hr). 相似文献
17.
Gregory A Hale Laura C Bowman Richard J Rochester Eli Benaim Helen E Heslop Robert A Krance Edwin M Horwitz John M Cunningham Xin Tong Deo Kumar Srivastava Rupert Handgretinger Deborah P Jones 《Biology of blood and marrow transplantation》2005,11(11):912-920
Hemolytic uremic syndrome (HUS) is an uncommon but potentially life-threatening complication of hematopoietic stem cell transplantation. We retrospectively studied the medical records of 293 children who underwent allogeneic bone marrow transplantation at St. Jude Children's Research Hospital between 1992 and 1999 to describe the clinical course of and to identify risk factors for transplant-associated HUS. Conditioning regimens included cyclophosphamide, cytarabine, and total body irradiation for patients with hematologic malignancies (n = 244); patients with nonmalignant diseases (n = 49) received disease-specific regimens. Grafts from unrelated or mismatched related donors were depleted of T lymphocytes, whereas matched sibling grafts were unmanipulated. All patients received cyclosporine as prophylaxis for graft-versus-host disease. Recipients of grafts from matched siblings also received pentoxifylline or short-course methotrexate. HUS developed in 28 (9.6%) patients at a median of 171 days after transplantation. We identified older donor age (P = .029), use of antithymocyte globulin in the conditioning regimen (P = .008), and recipient CMV seronegativity (P = .011) as being associated with an increased risk of HUS. With a multiple regression analysis, the use of antithymocyte globulin (beta = .86; P = .04) and recipient cytomegalovirus seronegativity (beta = .93; P = .035) remained significant risk factors for the development of HUS. 相似文献
18.
Krásná E Kolesár L Slavcev A Valhová S Kronosová B Jaresová M Stríz I 《Inflammation》2005,29(1):33-37
IL-18 is a multifunctional cytokine that augments both innate and acquired immunity and potentiates Th1 and Th2 reactions.
We studied the expression of IL-18 receptor (IL-18R) on renal and respiratory epithelial cell lines. Both cell lines upregulated
IL-18R mRNA and IL-18R membrane expression in response to TNF alpha and other proinflammatory cytokines. The function of IL-18R
was confirmed by induction of IL-8 release from epithelial cells in response to recombinant IL-18. Epithelial cells may represent
an important target for IL-18, mainly under inflammatory conditions associated with TNF alpha release. 相似文献
19.
Sigmundsdóttir H Johnston A Gudjónsson JE Valdimarsson H 《Clinical immunology (Orlando, Fla.)》2004,111(1):119-125
At both cutaneous and mucosal sites, interleukin (IL)-10, IL-12 and transforming growth factor (TGF)-beta are important regulators of chronic inflammatory disease, where cutaneous lymphocyte-associated antigen (CLA) and alphaE integrin (CD103) may be expressed. Stimulation with streptococcal pyrogenic exotoxin C (SpeC) increased the expression of CD103 by CD8+ but not CD4+ T cells. While adding IL-12 augmented the expression of CLA, superantigen-induced expression of CD103 was markedly suppressed by IL-12, which could be reversed by TGF-beta. Antibodies against TGF-beta inhibited, and a combination of anti-TGF-beta and IL-12 completely abrogated the induced CD103 expression. IL-10 strongly decreased the frequency of CLA+ and although not increasing the frequency of CD103+CD8+ T cells, the amount of CD103 expressed per cell was markedly increased. Thus, the expression of CLA and CD103 may be antagonistically regulated by IL-10 and IL-12 and the balance between these cytokines could influence the T cell migration of inflammatory cells into epithelial tissues. 相似文献
20.