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31.
Aortic valve stenosis is one of the most common valvular abnormalities, which can manifest as angina, syncope, dyspnoea and sudden cardiac death. Transcath  相似文献   
32.

Aims

To describe the safety and performance of STENTYS self-expandable bare metal stents (BMS) versus paclitaxel-eluting stents (PES) in saphenous vein grafts (SVGs).

Methods and Results

A randomised controlled trial was performed in four hospitals in three European countries between December 2011 and December 2013. Patients with de novo lesions (>50% stenosis) in an SVG with a diameter between 2.5–6?mm were included. Primary endpoint was late lumen loss at 6 months. Secondary endpoints included procedural success and the occurrence of major adverse cardiac events (MACE) at 12 months. A total of 57 patients were randomised to STENTYS self-apposing BMS (n = 27) or PES (n = 30). Procedural success was obtained in 89.5%. No significant differences in late lumen loss were found between BMS and PES at 6 months (0.53?mm vs 0.47; p = 0.86). MACE rates at 12 months were comparable in both groups (BMS 22.2% vs. PES 26.7%; p = 0.70).

Conclusions

Treatment of SVGs with STENTYS self-expandable stents is safe and effective. No significant differences were found in late lumen loss and MACE between BMS and PES.
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33.
34.
Iron is an indispensable element for vital activities in almost all living organisms. It is also a cofactor for many proteins, enzymes, and other essential complex biochemical processes. Therefore, iron trafficking is firmly regulated by Hepcidin (Hamp), which is regarded as the marker for iron accumulation. The disruption of iron homeostasis leads to oxidative stress that causes various human diseases, but this mechanism is still unclear. The aim of this study is to provide a better in vivo and in vitro understanding of how long‐term iron overload affects the gene expression and activities of some antioxidant enzymes, such as glucose 6‐phosphate dehydrogenase (G6PD), 6‐phosphogluconate dehydrogenase (6PGD), and glutathione reductase (GR) in the spleen. The findings of this study show that iron overload reduces the gene expression of G6pd, 6pgd, and Gr, but its actual effect was on the protein level.  相似文献   
35.
Drug-eluting stents (DES) are widely used as first choice devices in percutaneous coronary interventions. However, certain concerns are associated with the use of DES, i.e. delayed arterial healing with a subsequent risk of neo-atherosclerosis, late stent thrombosis and hypersensitivity reactions to the DES polymer. Bioresorbable vascular scaffolds are the next step in percutaneous coronary interventions introducing the concept of supporting the natural healing process following initial intervention without leaving any foreign body materials resulting in late adverse events. The first-generation devices have shown encouraging results in multiple studies of selected patients up to the point of full bioresorption, supporting the introduction in regular patient care. During its introduction in daily clinical practice outside the previously selected patient groups, a careful approach should be followed in which outcome is continuously monitored.  相似文献   
36.
We aimed to investigate whether or not the estrogen is playing any role in the effect of thyroid hormones on bone metabolism. The rats were divided into five groups. In the first group L-thyroxine-induced hyperthyroid rats were ovariectomized (OVX) while the OVX rats were administered L-thyroxine in the second group. 17beta-Estradiol (E2) was replaced in OVX rats in Group III. L-thyroxine and E2 were simultaneously administered to OVX rats in Group IV. The fifth group received sham operation. Blood samples taken from the tail vein of rats were analyzed for plasma T3, T4, TSH and serum interleukin (IL)-1beta, IL-6, tumor necrosis factor (TNF)alpha, calcium (Ca), phosphorous (P), parathyroid [corrected] hormone (PTH), alkaline phosphatase (t-ALP), bone-specific alkaline phosphatase (b-ALP) and E2. The levels of cytokines, t-ALP and b-ALP increased but PTH decreased, while there was no change in Ca and P levels in L-thyroxine-administrated rats. However, the levels of cytokines, Ca, P, PTH, t-ALP and b-ALP did not change in L-thyroxine-administered OVX rats. In OVX rats, the cytokines, t-ALP and b-ALP increased while Ca, P remained the same, but PTH decreased. L-thyroxine administration to OVX rats did not change the cytokines, Ca, P, PTH, t-ALP and b-ALP levels. The replacement of E2 in OVX rats decreased the cytokines, t-ALP and b-ALP values, increased PTH levels while there was no change in Ca and P. L-thyroxine and E2 administration to OVX rats increased the cytokines, t-ALP and b-ALP levels and decreased PTH, but Ca and P remained the same. In sham-operated rats, there was no change in all parameters compared to initial values. This study suggests that estrogen may play a role in the effects of thyroid hormones on bone metabolism.  相似文献   
37.
Rhizobium sp. strain NGR234 produces a flavonoid-inducible rhamnose-rich lipopolysaccharide (LPS) that is important for the nodulation of legumes. Many of the genes encoding the rhamnan part of the molecule lie between 87 degrees and 110 degrees of pNGR234a, the symbiotic plasmid of NGR234. Computational methods suggest that 5 of the 12 open reading frames (ORFs) within this arc are involved in synthesis (and subsequent polymerization) of L-rhamnose. Two others probably play roles in the transport of carbohydrates. To evaluate the function of these ORFs, we mutated a number of them and tested the ability of the mutants to nodulate a variety of legumes. At the same time, changes in the production of surface polysaccharides (particularly the rhamnan O antigen) were examined. Deletion of rmlB to wbgA and mutation in fixF abolished rhamnan synthesis. Mutation of y4gM (a member of the ATP-binding cassette transporter family) did not abolish production of the rhamnose-rich LPS but, unexpectedly, the mutant displayed a symbiotic phenotype very similar to that of strains unable to produce the rhamnan O antigen (NGRDeltarmlB-wbgA and NGROmegafixF). At least two flavonoid-inducible regulatory pathways are involved in synthesis of the rhamnan O antigen. Mutation of either pathway reduces rhamnan production. Coordination of rhamnan synthesis with rhizobial release from infection threads is thus part of the symbiotic interaction.  相似文献   
38.
High specific cellular nisin production was aimed by cycle changing the medium of Lactococcus lactis N8 and LAC48. The highest level of nisin production was reached with the 120 min cycles but maximal production was unstable. In shorter cycles (30 and 60 min) cells could be maintained in a high production state up to the end of the fermentation (28 and 14 cycles). N8 produced 19-fold and LAC48 15-fold more nisin with cycle changing the medium than without cycle incubation.  相似文献   
39.
Succinoglycans are bacterial exopolysaccharides with an octasaccharide repeating unit, composed of glucose and galactose in a 7:1 molar ratio of, and non-carbohydrate substituents, including pyruvate, succinate and acetate. The succinoglycans produced by four different strains of Sinorhizobium meliloti, gram-negative soil bacteria, were analyzed for their molecular weight distribution and degree of non-carbohydrate substitution, as well as their chemical properties were related to their rheological properties. These results showed that the ratio of high molecular weight to low molecular weight succinoglycan was varied from 0.50 to 2.36. Degree of succinylation among the bacterial strains was in the range of 0.30–1.90. Therefore, we concluded that each strain produced succinoglycans with different average degrees of polymerization and succinylation; and that these characteristics were correlated to the rheological properties of the solutions. The effect of molecular weight on the rheological properties appeared to be less than that of the succinyl group abundance.  相似文献   
40.

Background

The management of brachial plexus injuries due to gunshot wounds is a surgical challenge. Better surgical strategies based on clinical and electrophysiological patterns are needed. The aim of this study is to clarify the factors which may influence the surgical technique and outcome of the brachial plexus lesions caused by gunshot injuries.

Methods

Two hundred and sixty five patients who had brachial plexus lesions caused by gunshot injuries were included in this study. All of them were male with a mean age of 22 years. Twenty-three patients were improved with conservative treatment while the others underwent surgical treatment. The patients were classified and managed according to the locations, clinical and electrophysiological findings, and coexisting lesions.

Results

The wounding agent was shrapnel in 106 patients and bullet in 159 patients. Surgical procedures were performed from 6 weeks to 10 months after the injury. The majority of the lesions were repaired within 4 months were improved successfully. Good results were obtained in upper trunk and lateral cord lesions. The outcome was satisfactory if the nerve was intact and only compressed by fibrosis or the nerve was in-contunuity with neuroma or fibrosis.

Conclusion

Appropriate surgical techniques help the recovery from the lesions, especially in patients with complete functional loss. Intraoperative nerve status and the type of surgery significantly affect the final clinical outcome of the patients.  相似文献   
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