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11.
Extracts of the tunicate Cynthia savignyi from the Moroccan Atlantic sea have been investigated in five bioassays. The first is an antibacterial test against Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus and Agrobacterium tumefaciens; the second is an antifungal test against three tomato pathogenic fungi, Botrytis cinerea, Fusarium oxysporum and Verticillium albo-atrum; the third is a test based to the ability to reduce DNA peak size in procedures using an HPLC system for detection of antitumour agents; the fourth is a toxicity test using larva of Artemia salina; and the last is an enzymatic inhibitory test against papain and trypsin. For all the bioassays, extracts of C. savignyi were found to be bioactive. This result suggests that this tunicate is able to produce biologically active agents required for an overall defence against their predators.  相似文献   
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The numbers and diversity of microbes in ecosystems within and around us is unmatched, yet most of these microorganisms remain recalcitrant to in vitro cultivation. Various high-throughput molecular techniques, collectively termed multi-omics, provide insights into the genomic structure and metabolic potential as well as activity of complex microbial communities. Nonetheless, pure or defined cultures are needed to (1) decipher microbial physiology and thus test multi-omics-based ecological hypotheses, (2) curate and improve database annotations and (3) realize novel applications in biotechnology. Cultivation thus provides context. In turn, we here argue that multi-omics information awaits integration into the development of novel cultivation strategies. This can build the foundation for a new era of omics information-guided microbial cultivation technology and reduce the inherent trial-and-error search space. This review discusses how information that can be extracted from multi-omics data can be applied for the cultivation of hitherto uncultured microorganisms. Furthermore, we summarize groundbreaking studies that successfully translated information derived from multi-omics into specific media formulations, screening techniques and selective enrichments in order to obtain novel targeted microbial isolates. By integrating these examples, we conclude with a proposed workflow to facilitate future omics-aided cultivation strategies that are inspired by the microbial complexity of the environment.  相似文献   
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This paper investigates the behavior of large diameter bearing bolted joint in order to evaluate fatigue resistance of the screws. Based on experimental results, a sector of a slewing bearing is modeled using 3D finite elements. The model is built via hypothesis of sine-distributed efforts on the roller tracks. The simulations are carried out for the most loaded screw, which is located in the symmetry plane. Experimental measures on equipped screws are checked against numerical 3D simulations. This validates the numerical modeling method. Then the numerical model is used to evaluate the influence of several geometrical and physical parameters. The preload intensity reveals to be the major parameter. The bushes’ height affects load filtering and improves fatigue strength of the screws. The height of the mounting tubes smoothes potential stiff points. The friction coefficient between the ring and the mounting is investigated as well. Eventually, several observations are made which lead to design recommendations for fatigue sizing of the slewing bearing screwed joints.  相似文献   
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The major indication for pancreas or islet transplantation is diabetes mellitus type I. This process has to supply the insulin necessity keeping glucose under control. We have studied isogenic islet transplantation on the rat (WAG-RT1u) liver. The method of isolation and purification of the islets obtained 2.834 +/- 551.64 islets with purity of 83 +/- 2.45%. Diabetes was induced by streptozotocin and seric glucose prior transplantation was 35 mmol/L. The islet transplantation of 2.834 +/- 551.64 islets in the rat liver has normalized glucose test from 9.62 +/- 2.65 mmol/L 10 days after transplantation to 7.43 +/- 0.27 mmol/L later in the follow-up (P < 0.05). The median survival time of the islets was 73 days. In conclusion both the method of isolation and purification of the islets and islet transplantation was effective in the control of the diabetes induced by streptozotocin with median survival time of both islet and rat more than 73 days when rats were sacrified.  相似文献   
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Twenty patients in whom sphincteroplasty was performed are presented. In 12 cases the indication was choledocholithiasis with stone impacted in the distal bile duct; 5 cases with choledocholithiasis and oddian stenosis, and 3 cases with residual choledocholithiasis associated with oddian stenosis. The average length of the incision of the ampullary area was 25 mm. The postoperative control made by tube cholangiography evidenced the presence of a wide open choledochoduodenal opening. Amylase activity was followed in all patients. One case of acute pancreatitis and one case of choledochal fistula were recorded as postoperative complications.  相似文献   
20.

Background

In patients with heart failure, left bundle branch block (LBBB) seems to be associated with an increased risk of cardiovascular mortality.

Purpose

The purpose of this study is to determine the in-hospital outcome of congestive heart failure patients with LBBB versus those without.

Methods

We conducted a prospective observational study at the Department of Intensive Care and Rhythmology at the Mohammed V Military Hospital of Rabat, where 330 patients were admitted for heart failure between January 2008 and September 2012. Screening out patients with missing data yielded a cohort of 274 patients. Among the 274 patients, only 110 had LBBB and a left ventricular ejection fraction lower than 50%. We randomly selected a subset of 110 patients diagnosed as non-LBBB to ensure a significant statistical comparison between LBBB and non-LBBB patients. We therefore considered two groups in our analysis: 110 heart failure (HF) patients with LBBB and 110 HF patients without LBBB. Patients with incomplete records were excluded.

Results

Male gender was dominant in both groups (82.7% vs. 66.7%, p = 0.005). Patients with LBBB had a higher prevalence of idiopathic dilated cardiomyopathy (39.1% vs. 4.8%, p < 0.001); and a higher prevalence of previous hospitalization for heart failure (64.5% vs. 23.3%, p < 0.001). The left ventricular ejection fraction was significantly lower in the group with LBBB (25.49% vs. 39.53%, p < 0.001). Age, cardiovascular risk factors, rhythmic and thromboembolic complications did not significantly differ. In patients with LBBB, 61.8% received cardiac resynchronization therapy performed both during the index hospital stay (50.9%) and previously (10.9%). Hospital outcome was marked by 20 in-hospital deaths in the group with LBBB and eight deaths in the group without LBBB (p = 0.008).

Conclusion

Our analysis emphasizes increased in-hospital mortality and higher disease severity, over a short period of stay, in heart failure patients with left bundle branch block.  相似文献   
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