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521.
CYLIC PEPTIDES     
Two diastereomeric cyclic tetrapeptides with a sequence of cyclo (-D (and L)-Tyr (Me)-L-Ile-L-Pro-L-Leu-) (ID and IL) have been synthesized, which are simplified analogs of a phytotoxic peptide Cyl-2, and contain an L-proline and an L-leucine residue in place of an L-pipecolic acid and a 2-amino-8-oxo-9,10-epoxydecanoic acid residue, respectively, in Cyl-2. The cyclization of the H-D-Tyr(Me)-L-Ile-L-Pro-L-Leu-ONSu proceeded smoothly to give ID in excellent yield (50%), but the cyclization of H-L-Tyr(Me)-L-Ile-L-Pro-L-Leu-ONSu gave IL in much lower yield (10%). Based on the results of 1H- and 13C-n.m.r. studies, differential N-methylation and model buildings of ID, the backbone structure of ID has been proposed to be a unique trans-trans-cis-trans conformation, the L-Ile-L-Pro bond being cis.  相似文献   
522.
ABSTRACT Azosemide produced bent long bones such as wavy ribs in rat fetuses, but these abnormalities could not be found in the adult offspring. In the present study, the morphological sequence from appearance to disappearance of wavy ribs was examined in cartilage-bone double stained specimens of fetuses and pups from mothers treated with azosemide on day 16 of gestation. The first detected change of the skeletal abnormalities was inhibition of bone deposition in the ossification centers of fetuses on day 17 of gestation. A bend first appeared on day 18 of gestation, and consisted of cartilage and portion stained neither alcian blue nor alizarin red S. Ossification began at this stage. From day 19 of gestation onward, ossification progressed toward the ends of the cartilage model including the bent region. The bend disappeared in most pups as bone in the bent region grew on days 10–14 postpartum. The present findings imply that the bend may be caused by difference in growth between cartilaginous and unstained portions, and a surface remodeling of bones may straighten the bend in the subsequent bone growth.  相似文献   
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525.

Objective:

To evaluate the biocompatibility and the setting time of Portland cement clinker with or without 2% or 5% calcium sulfate and MTA-CPM.

Material and Methods:

Twenty-four mice (Rattus norvegicus) received subcutaneously polyethylene tubes filled with Portland cement clinker with or without 2% or 5% calcium sulfate and MTA. After 15, 30 and 60 days of implantation, the animals were killed and specimens were prepared for microscopic analysis. For evaluation of the setting time, each material was analyzed using Gilmore needles weighing 113.5 g and 456.5 g, according to the ASTM specification Number C266-08 guideline. Data were analyzed by ANOVA and Tukey''s test for setting time and Kruskal-Wallis and Dunn test for biocompatibility at 5% significance level.

Results:

Histologic observation showed no statistically significant difference of biocompatibility (p>0.05) among the materials in the subcutaneous tissues. For the setting time, clinker without calcium sulfate showed the shortest initial and final setting times (6.18 s/21.48 s), followed by clinker with 2% calcium sulfate (9.22 s/25.33 s), clinker with 5% calcium sulfate (10.06 s/42.46 s) and MTA (15.01 s/42.46 s).

Conclusions:

All the tested materials showed biocompatibility and the calcium sulfate absence shortened the initial and final setting times of the white Portland cement clinker.  相似文献   
526.
Tetra-spans transmembrane family (TSTF) members (CD9, CD37, CD53, CD63, CD81 and CD82) have potent effects on cell growth, motility and adhesion in various cells. However, little is known about their expression in human skin. Using immunohistological techniques, we have studied the localization of all six members of TSTF in normal and carcinomatous human keratinocytes. CD9, CD81 and CD82 were expressed in the entire living layers of the epidermis. Their staining pattern was quite similar, and was mainly intercellular with occasional intracellular immunoreactivity. CD53 expression was confined to the intercellular spaces of the upper spinous or granular layer in the normal epidermis. No clear-cut expression of CD63 could be detected in the epidermis. CD37 was not detected at all. Cultured human keratinocytes also expressed CD9, CD81 and CD82 at the surface membrane of cell-cell boundaries. Expression of CD37 and CD53 was negative in cultured keratinocyte, while CD63 was clearly localized in the cytoplasmic lysosomes. An immunoprecipitation assay revealed that α3β1 integrin is molecularly associated with CD9. The expression of CD9, CD81 and CD82 was markedly down-regulated in basal cell carcinoma but not in Bowen's disease. The abundant and differential expression of TSTF molecules and the selective association of CD9 with α3β1 integrin suggest that the TSTF molecules may be involved in the regulation of epidermal differentiation and integrity in vivo.  相似文献   
527.
The autologous mixed lymphocyte reaction (auto-MLR) was studied to test the interactions between immunocompetent cells in patients with psoriasis. The auto-MLR in 20 patients with psoriasis was significantly lower than in 16 normal controls. Lower values were found in untreated psoriatic patients than in those in remission following treatment. The values in the latter group were significantly lower than in controls and in six patients with atopic dermatitis in remission. The tendency for an increase in the auto-MLR with a decrease in disease activity was further confirmed in five patients studied before and after treatment. In contrast, the allogeneic lymphocyte reaction (allo-MLR) in psoriatics was similar to that in normal controls.  相似文献   
528.
Aim : The effect of lansoprazole plus amoxycillin on curing Helicobacter pylori infection and peptic ulcer recurrence was evaluated.
Method : The study group was composed of 68 patients with gastric ulcers and 51 with duodenal ulcers, all were H. pylori -positive. The participants were assigned at random to the lansoprazole alone group (lansoprazole 30 mg o.m. for 6 or 8 weeks) or the lansoprazole plus amoxycillin group (lansoprazole alone regimen plus amoxycillin at 500 mg q.d.s. concomitantly for the first 2 weeks). Healed patients were not given maintenance treatment with acid secretion inhibitors. The cure rate for H. pylori infection and the ulcer recurrence rate after 1 year were investigated.
Result : The cure rate for H. pylori infection was 4.2% in patients receiving lansoprazole alone and 38.5% in patients receiving lansoprazole plus amoxycillin ( P < 0.01) for gastric ulcers, and 0% in patients receiving lansoprazole alone and 61.9% in patients receiving lansoprazole plus amoxycillin ( P <0.001) for duodenal ulcers. The recurrence rate was 42.3% in patients receiving lansoprazole alone and 28.6% in patients receiving lansoprazole plus amoxycillin for gastric ulcers, and 66.7% for patients receiving lansoprazole alone and 11.1% for patients receiving lansoprazole plus amoxycillin ( P <0.001) for duodenal ulcers. None of the patients with gastric or duodenal ulcers cured of H. pylori infection had a recurrence.
Conclusion : Concomitant use of lansoprazole and amoxycillin increased the curative effects on H. pylori infection. However, the cure rates with this regimen remained inadequate.  相似文献   
529.
Dabigatran and warfarin are oral anticoagulant drugs widely used for the prevention of stroke in patients with atrial fibrillation. The objective of this study was to evaluate the interaction between aging and dabigatran- and warfarin-induced gastrointestinal (GI) and nervous system hemorrhage using data available in the FDA Adverse Event Reporting System (FAERS) database.We analyzed reports of hemorrhagic events in the GI and nervous system recorded in the FAERS database between 2004 and 2014 using an adjusted reporting odds ratio (ROR).We demonstrated that dabigatran-associated GI hemorrhage was significantly increased in patients over the age of 80 years. The RORs of dabigatran increased with increasing age, although aging had little effect on warfarin-associated GI hemorrhage. The ROR for anticoagulant-associated nervous system hemorrhage was not significantly affected by aging, as compared to GI hemorrhage.Our results indicate that the excretion of dabigatran may be affected by aging, as compared to warfarin, likely due to renal function decline. Our results emphasize the need for physicians to closely monitor GI bleeding in aging patients, because it is closely related to renal function deterioration.  相似文献   
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