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991.
ObjectiveThe aim of our study was to analyze sonication and Maki techniques for diagnosis of catheter tip colonization and catheter-related bloodstream infection (CRBSI) on patients admitted to ICU.Material and methodsObservational and prospective study in one Intensive Care Unit. Patients with some central venous catheter (CVC) at least for 7 days and catheter-related infection (CRI) suspicion (new episode of fever or sepsis) were included. We performed Maki technique followed by sonication of catheter tip. We compared area under the curve (AUC) of Maki, sonication, and techniques combination to diagnosis catheter tip colonization and CRBSI.ResultsWe included 94 CVC from 87 CRI suspicion episodes. We found 14 cases of catheter tip colonization and 10 cases of CRBSI. Of the 14 catheter tip colonization cases, 7 (50.0%) were detected by Maki and sonication techniques, 6 (42.9%) were detected only by Maki technique, and 1 (7.1%) was detected only by sonication technique. Of the 10 CRBSI, 6 (60.0%) were detected by Maki and sonication techniques, 4 (40.0%) were detected only by Maki technique, and any only by sonication technique. We found higher AUC in Maki technique than in sonication technique to diagnosis of CRBSI (p=0.02) and to diagnosis of catheter tip colonization (p=0.03). No significant differences were found in AUC between Maki technique and combination techniques for diagnosis of catheter tip colonization (p=0.32) and of CRBSI (p=0.32).Conclusion.:Sonication did not provide reliability to Maki technique for diagnosis of catheter tip colonization and CRBSI.  相似文献   
992.
Free zinc is considered to be the exchangeable and biological active form of zinc in serum, and is discussed to be a suitable biomarker for alterations in body zinc homeostasis and related diseases. Given that coronavirus disease 2019 (COVID-19) is characterized by a marked decrease in total serum zinc, and clinical data indicate that zinc status impacts the susceptibility and severity of the infection, we hypothesized that free zinc in serum might be altered in response to SARS-CoV-2 infection and may reflect disease severity. To test this hypothesis, free zinc concentrations in serum samples of survivors and nonsurvivors of COVID-19 were analyzed by fluorometric microassay. Similar to the reported total serum zinc deficit measured by total reflection X-ray fluorescence, free serum zinc in COVID-19 patients was considerably lower than that in control subjects, and surviving patients displayed significantly higher levels of free zinc than those of nonsurvivors (mean ± SD; 0.4 ± 0.2 nM vs. 0.2 ± 0.1 nM; p = 0.0004). In contrast to recovering total zinc concentrations (r = 0.706, p < 0.001) or the declining copper–zinc ratio (r = −0.646; p < 0.001), free zinc concentrations remained unaltered with time in COVID-19 nonsurvivors. Free serum zinc concentrations were particularly low in male as compared to female patients (mean ± SD; 0.4 ± 0.2 nM vs. 0.2 ± 0.1 nM; p = 0.0003). This is of particular interest, as the male sex is described as a risk factor for severe COVID-19. Overall, results indicate that depressed free serum zinc levels are associated with increased risk of death in COVID-19, suggesting that free zinc may serve as a novel prognostic marker for the severity and course of COVID-19.  相似文献   
993.
994.
Papillary tumor of the pineal region is a rare neuroepithelial tumor characterized by papillary architecture and epithelial cytology, immunopositivity for cytokeratin and ependymal differentiation. It is considered grade II–III by the World Health Organization and was first described by Jouvet in 2003. We present a 34-year-old male with headaches, blurred vision and normal examination. Radiological study showed a nodulocystic lesion in the pineal region compatible with pineocytoma. Surgery was performed using an infratentorial supracerebellar approach, finding a cystic tumor in the quadrigeminal cistern which was completely resected. Histopathology reported a papillary tumor of the pineal region. The patient made good progress without adjuvant therapy, and after 57 months of follow-up he remained asymptomatic and free of recurrence. A review of the literature was performed to collect all the cases published with gross total resection and no complementary treatment. In conclusion, there is still much to be learned about the pathogenesis, prognosis and management of this tumor.  相似文献   
995.
Spontaneous modulations of corticospinal excitability during action observation have been interpreted as evidence for the activation of internal motor representations equivalent to the observed action. Alternatively or complementary to this perspective, growing evidence shows that motor activity during observation of rhythmic movements can be modulated by direct visuomotor couplings and dynamical entrainment. In‐phase and anti‐phase entrainment spontaneously occur, characterized by cyclic movements proceeding simultaneously in the same (in‐phase) or opposite (anti‐phase) direction. Here we investigate corticospinal excitability during the observation of vertical oscillations of an index finger using Transcranial Magnetic Stimulation (TMS). Motor‐evoked potentials (MEPs) were recorded from participants’ flexor and extensor muscles of the right index finger, placed in either a maximal steady flexion or extension position, with stimulations delivered at maximal flexion, maximal extension or mid‐trajectory of the observed finger oscillations. Consistent with the occurrence of dynamical motor entrainment, increased and decreased MEP responses – suggesting the facilitation of stable in‐phase and anti‐phase relations but not an unstable 90° phase relation – were found in participants’ flexors. Anti‐phase motor facilitation contrasts with the activation of internal motor representation as it involves activity in the motor system opposite from activity required for the execution of the observed movement. These findings demonstrate the relevance of dynamical entrainment theories and methods for understanding spontaneous motor activity in the brain during action observation and the mechanisms underpinning coordinated movements during social interaction.  相似文献   
996.
We analyzed the clinical, angiographic, and late intravascular ultrasonographic findings from 140 patients whose in-stent restenosis was treated with sirolimus-eluting stents. In-stent restenosis remains the main limitation to percutaneous coronary revascularization and has a high recurrence rate after bare stent implantation. From May 2002 through July 2003, we studied 140 patients with clinical restenosis after bare-stent treatment. In 107 patients, in-stent restenosis occurred de novo; in 28 patients, this was the 2nd restenosis; and in another 5, it was the 3rd occurrence. A sirolimus-eluting stent was implanted directly after angiographic evaluation of the in-stent restenosis in 79 patients and after pre-dilation in 61 patients. All patients were given the following antithrombotic regimen: low-molecular-weight heparin, ticlopidine, and aspirin for 1 month, followed by clopidogrel and aspirin for 1 year. Primary success was achieved in 137 patients. Three patients had a non-Q wave myocardial infarction. At the 1-month evaluation, 2 patients had died: 1 due to subacute stent thrombosis and another due to acute mesenteric ischemia. After a mean follow-up of 16 +/- 4 months, the major adverse cardiac events were acute myocardial infarction due to late stent thrombosis in 2 patients and the need for target lesion revascularization in 15 patients. Late angiographic evaluation was performed in 97 patients (69%), 16 of whom had new restenosis: 14 of the restenoses were intrastent, and 2 were at the edges of the stent. Our results suggest that sirolimus-eluting stents are effective in the prevention of in-stent restenosis and, therefore, may become the leading treatment alternative for patients with in-stent restenosis.  相似文献   
997.
Eighteen-month-old Sprague-Dawley rats present age-related alterations in lipid and glucose metabolism and are resistant to the effect of PPARalpha-activating hypolipidemic drugs, such as gemfibrozil. We tested if these animals were responsive to the administration of rosiglitazone, an insulin-sensitizer acting on PPARgamma. We determined in 18-month-old female Sprague-Dawley rats treated for 21 days with a daily dose of 3mg gemfibrozil/kg or 3mg rosiglitazone/kg: (i) plasma concentrations of total cholesterol (TC), triglycerides (TG), nonesterified fatty acids (NEFA), glucose, insulin and leptin, (ii) hepatic concentrations of TG, NEFA and cholesteryl esters (CE), and (iii) the liver expression and binding activity of peroxisome proliferator-activated receptor alpha (PPARalpha), and several of its target genes, hepatic nuclear factor-4 (HNF-4), and liver X receptor alpha (LXRalpha). Although gemfibrozil induced mild effects on hepatic PPARalpha, HNF-4, and LXRalpha, only rosiglitazone significantly reduced plasma TG (59%), glucose (19%), insulin (61%), and leptin (66%), and liver TG (43%), CE (49%), and NEFA (27%). These changes were associated to an increased body weight gain and a decrease in visceral fat (8.7-fold and 37% vs. control females, respectively). The beneficial effect of rosiglitazone treatment in 18-month-old female rats could be related to a direct effect on white adipose tissue.  相似文献   
998.
Whatever the cause, it is extraordinary that dozens of genera of large mammals became extinct during the late Quaternary throughout the Western Hemisphere, including 90% of the genera of the xenarthran suborder Phyllophaga (sloths). Radiocarbon dates directly on dung, bones, or other tissue of extinct sloths place their "last appearance" datum at approximately 11,000 radiocarbon years before present (yr BP) or slightly less in North America, approximately 10,500 yr BP in South America, and approximately 4,400 yr BP on West Indian islands. This asynchronous situation is not compatible with glacial-interglacial climate change forcing these extinctions, especially given the great elevational, latitudinal, and longitudinal variation of the sloth-bearing continental sites. Instead, the chronology of last appearance of extinct sloths, whether on continents or islands, more closely tracks the first arrival of people.  相似文献   
999.
PURPOSE: Preanastomotic recurrence and stricturing after surgery for ileocolic Crohn's disease is a frequent, unexplained phenomena that may lead to prompt reoperation. The aim of this study was to determine whether a wide-lumen stapled anastomosis (side-to-side, functional end-to-end) provides better outcome than a conventional sutured end-to-end anastomosis METHOD: A case-control comparative analysis of patients with Crohn's disease from two inflammatory bowel disease centers treated with wide-lumen stapled anastomosis and a matched (age and gender) group treated with conventional sutured end-to-end anastomosis was performed. RESULTS: A total of 138 patients with Crohn's disease were treated, 69 with wide-lumen stapled anastomosis and 69 with conventional sutured end-to-end anastomosis. Preoperative therapy, number of previous resections, indication for operation, and length of bowel resected were similar in both groups. Fewer complications occurred after wide-lumen stapled anastomosis (P=0.048). A total of 55 patients developed recurrent Crohn's disease symptoms, 39 (57 percent) in the conventional sutured end-to-end anastomosis and 16 (24 percent) in the wide-lumen stapled anastomosis group. Median follow-up was 70 and 46 months, respectively. After conventional sutured end-to-end anastomosis 18 reoperations were required, 15 for anastomotic stricture and 3 for fistulization. After wide-lumen stapled anastomosis three reoperations were necessary, two for stricture and one for fistulization. The cumulative reoperation rate for anastomotic recurrence was significantly lower (P=0.017; log-rank test) for the wide-lumen stapled anastomosis group. CONCLUSION: Wide-lumen stapled anastomosis is as safe as conventional sutured end-to-end anastomosis and results in a lower incidence of symptomatic recurrent Crohn's disease and need for reoperation. Further prospective study of the wide-lumen stapled anastomosis technique is necessary to define the precise role of this operation in patients with Crohn's disease.Read at The American Society of Colon and Rectal Surgeons' 100th Anniversary and Tripartite Meeting, Washington, D.C., May 1 to 6, 1999.  相似文献   
1000.
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