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11.

Purpose  

Use of biosutures in animal models of colonic anastomoses is associated with decreased adhesions without affecting anastomotic strength. This study aimed to evaluate the effect of biosutures on colonic anastomoses kept free of adhesions by peritoneal instillation of icodextrin 4%.  相似文献   
12.
We report the case of a 70 years old patient hospitalized for renal insufficiency and deterioration of the general state. The electrophoresis of serum proteins on freezing of agarose reveals the presence of a discrete peak of monoclonal pace on the level of the gammaglobulines identified by serum immunofixation like IgM of the kappa type. The research of the cryoglobulinemia carried out in a laboratory of city was made positive and typified like a monoclonal cryoglobulinemia IgM kappa, thus directing the diagnosis towards a disease of Waldenstr?m. However, the result of the biopsy medullary made exclude any lymphoprolifératif syndrome. The positivity of the serology of hepatitis B justified a second request for study of the cryoglobulinemia, carried out within our laboratory. The cryoglobuline was typified like mixed (IgM kappa monoclonal and IgG polyclonales). This result associated with the immunological assessment and the renal biopsy made retain for our patient the diagnosis of a kidney vasculitis connected to an infection chronicle by the virus of hepatitis B. This observation points out the interest of the preanalytic, analytic and post analytic phases in the study of the cryoglobulinemias. A good technical control is today the only guarantee of the quality of the result of this examination which has large importance in internal medicine in the etiologic assistance with the diagnosis of certain clinical demonstrations.  相似文献   
13.
14.
This study evaluated in vitro the bond strength of Epiphany sealer prepared with resinous solvent of Epiphany system (Thinning resin) by using a push-out test. Forty maxillary canines were sectioned transversally below the cementoenamel junction to provide 4-mm-thick dentin disks that were centered in aluminum rings and embedded in acrylic resin. Root canals were prepared with tapered diamond bur. Intraradicular dentin was treated with 1% NaOCl for 30 minutes, 17% ethylenediaminetetraacetic acid for 5 minutes, and flushed with distilled water for 1 minute. The specimens were randomly distributed into 4 groups (n = 10) according to the filling material: GI, Epiphany without photoactivation; GII, Epiphany prepared with solvent without photoactivation; GIII, Epiphany followed by photoactivation; and GIV, Epiphany prepared with solvent followed by photoactivation. After the setting time, the specimens were submitted to the push-out test. The highest mean value (14.91 ± 2.82 MPa) was obtained with Epiphany prepared with solvent followed by photoactivation (GIV), which was statistically different (P < .01) from the other groups. Groups I (8.15 ± 2.47 MPa), II (9.46 ± 2.38 MPa), and III (9.80 ± 2.51 MPa) had inferior bond strength values and were statistically similar among themselves (P > .01). The resinous solvent of Epiphany system increased the bond strength of Epiphany sealer to dentin walls when followed by photoactivation.  相似文献   
15.
Two patients presenting with urinary fistulas following partial resection of hydronephrotic kidneys were successfully treated with selective arterial embolization causing functional ablation of the remaining renal parenchyma. This technique is simpler than surgical reexploration.  相似文献   
16.
Gene gun mucosal DNA immunization of sheep with a plasmid expressing the env gene of Maedi-Visna virus (MVV) was used to examine the protection against MVV infection in sheep from a naturally infected flock. For immunization, sheep were primed with a pcDNA plasmid (pcDNA-env) encoding the Env glycoproteins of MVV and boosted with combined pcDNA-env and pCR3.1-IFN-gamma plasmid inoculations. The pcDNA plasmid used in the control group contained the lacZ coding sequences instead of the env gene. Within a month post-challenge, the viral load in the vaccinated group was lower (p < or = 0.05) and virus was only detected transiently compared with the control group. Furthermore, 2 months later, neutralizing antibodies (NtAb) were detected in all the control animals and none of the vaccinated animals (p < or = 0.01). These results demonstrated a significant early protective effect of this immunization strategy against MVV infection that restricts the virus replication following challenge in the absence of NtAb production. This vaccine protective effect against MVV infection disappeared after two years post-challenge, when active replication of MVV challenge strain was observed. Protection conferred by the vaccine could not be explained by OLA DRB1 allele or genotype differences. Most of the individuals were DRB1 heterozygous and none was totally resistant to infection.  相似文献   
17.
2-Phenylselenenyl-1,8-cineole (PSC) increased both the pentobarbital-induced sleeping time and the reaction time (up to 2 h) in the tail immersion method. PSC also caused dose-dependent inhibition of acetic acid induced writhing with maximum inhibition of 93.4% and was approximately 8.5-fold more potent than 1,8-cineole. These findings show that PSC presents sedative effect and significant antinociceptive activity.  相似文献   
18.
Myosin-V is involved in organelle and vesicle trafficking in Saccharomyces cerevisiae and in other eukaryotic cells from yeast to human. In the present study, we determined by FACS that the major subpopulations of the peripheral blood mononuclear cells express myosin-V with similar fluorescence intensity. Confocal microscopy showed intense labeling for myosin-V at the centrosomal region and a punctate staining throughout the cytoplasm, frequently associated with the central microtubule arrays and the actin-rich cortex. Some degree of overlap with an endolysosomal marker and dynein light-chain 8 k was found at the cell center. Striking colocalization was observed with the major histocompatibility complex (MHC) class II molecules near the cell surface. Treatment with phytohemagglutinin, which induces T-lymphocyte activation, associated with MHC class II expression, increased the levels of myosin-V protein and mRNA for the three members of class V myosins. These data suggest that class V myosins might be involved in relevant functions in the immune response.  相似文献   
19.
Levonorgestrel (13beta-ethyl-17alpha-ethynyl-17beta-hydroxy-4-gonen-3-one), a potent contraceptive progestin stimulates growth and proliferation of cultured breast cancer cells through a receptor-mediated mechanism, even though levonorgestrel does not bind to the oestrogen receptor (ER). To assess whether the oestrogen-like effects induced by this synthetic progestin are exerted via its metabolic conversion products, we studied the binding affinity of three A-ring levonorgestrel derivatives to the ER and their capability to transactivate an oestrogen-dependent yeast system co-transfected with the human ER gene and oestrogen responsive elements fused to a beta-galactosidase reporter vector. The results demonstrated that the 3beta,5alpha reduced levonorgestrel derivative and to a lesser extent its 3alpha isomer interact with the oestrogen receptor, with a significantly lower relative binding affinity (2.4% and 0.4%, respectively) than that of oestradiol (100%), while levonorgestrel does not. Both levonorgestrel metabolites were able to activate, in a dose-dependent manner, the beta-galactosidase reporter gene in the yeast expression system, an effect that was precluded by a steroidal antioestrogen. The oestrogenic potency of levonorgestrel metabolites was significantly lower (750-fold) than that of oestradiol. Furthermore, high doses of 3beta,5alpha levonorgestrel (2.5 mg/day/6 days) induced an increase of oestrogen-dependent progestin receptor in the anterior pituitary of castrated rats. The overall data offer a plausible explanation for the weak oestrogenic effects induced by high, non-pharmacological doses of levonorgestrel.  相似文献   
20.
Protein misfolded oligomers are thought to be the primary pathogenic species in many protein deposition diseases. Oligomers by the amyloid-β peptide play a central role in Alzheimer's disease pathogenesis, being implicated in synaptic dysfunction. Here we show that the oligomers formed by a protein that has no link with human disease, namely the N-terminal domain of HypF from Escherichia coli (HypF-N), are also synaptotoxic. HypF-N oligomers were found to (i) colocalize with post-synaptic densities in primary rat hippocampal neurons; (ii) induce impairment of long-term potentiation in rat hippocampal slices; and (iii) impair spatial learning of rats in the Morris Water Maze test. By contrast, the native protein and control nontoxic oligomers had none of such effects. These results raise the importance of using HypF-N oligomers as a valid tool to investigate the pathogenesis of Alzheimer's disease, with advantages over other systems for their stability, reproducibility, and costs. The results also suggest that, in the context of a compromised protein homeostasis resulting from aggregation of the amyloid β peptide, a number of oligomeric species sharing common synaptotoxic activity can arise and cooperate in the pathogenesis of the disease.  相似文献   
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