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排序方式: 共有1458条查询结果,搜索用时 10 毫秒
41.
Influence of circadian rhythm on mortality after myocardial infarction: data from a prospective cohort of emergency calls 总被引:1,自引:0,他引:1
Manfredini R Boari B Bressan S Gallerani M Salmi R Portaluppi F Mehta RH 《The American journal of emergency medicine》2004,22(7):555-559
Myocardial infarction (MI) occurs more frequently in the morning as a result of the concomitant unfavorable timing of several physiological parameters and/or biochemical conditions. However, little is known about the possible influence of this circadian pattern on prognosis. To evaluate whether the time of symptom onset could potentially influence mortality from acute MI, this prospective study considered all consecutive MIs admitted to the ED of Ferrara, Italy, after a call to the Emergency Coordinating Unit from January 1, 1998, to December 31, 2001. The total sample consisted of 442 MIs (mean age, 68.7 years; males, 72%). Eighty patients (males, 82.5%) died in the ED; the remaining 362 were admitted to the hospital. Of these, 50 (males, 60%) died during their hospital stay. Based on the timing of their symptom onset, cases were categorized both into 24 1-hour intervals and four 6-hour intervals (midnight to 5:59 am, 6:00 am to 11:59 am, noon to 5:59 pm, and 6:00 pm to 11:59 pm), and the circadian distributions of fatal versus nonfatal MIs were compared. The circadian variation of MI peaked between 6:00 am and noon (P < .001), and in this period, there was a trend toward a higher frequency of fatal cases (41.5% vs. 35.2%; chi(2) = 1.911, P = .167). To verify whether this higher frequency of fatal events in the morning hours could be related to possible higher severity of cases observed in that hours, a further separate analysis considering age, infarct site, and peak levels of MB was made. Again, no significant temporal differences among the four 6-hour intervals were found between fatal and nonfatal Mis, although a trend toward older age was observed in morning MIs. Not only the frequency, but also the mortality, of acute MI could be increased in the morning hours. This could be of practical interest for emergency doctors and could have significant implications for acute treatment, because several studies have reported a lowered efficacy of thrombolytic drugs in the morning hours. 相似文献
42.
Erika Fantozzi Erlinda Rama Cinzia Calvio Benedetta Albini Pietro Galinetto Marcella Bini 《Materials》2021,14(11)
Spinel phases, with unique and outstanding physical properties, are attracting a great deal of interest in many fields. In particular, MgFe2O4, a partially inverted spinel phase, could find applications in medicine thanks to the remarkable antibacterial properties attributed to the generation of reactive oxygen species. In this paper, undoped and Ag-doped MgFe2-xAgxO4 (x = 0.1 and 0.3) nanoparticles were prepared using microwave-assisted combustion and sol–gel methods. X-ray powder diffraction, with Rietveld structural refinements combined with micro-Raman spectroscopy, allowed to determine sample purity and the inversion degree of the spinel, passing from about 0.4 to 0.7 when Ag was introduced as dopant. The results are discussed in view of the antibacterial activity towards Escherichia coli and Staphylococcus aureus, representative strains of Gram-negative and Gram-positive bacteria. The sol–gel particles were more efficient towards the chosen bacteria, possibly thanks to the nanometric sizes of metallic silver, which were well distributed in the powders and in the spinel phase, with respect to microwave ones, that, however, acquired antibacterial activity after thermal treatment, probably due to the nucleation of hematite, itself displaying well-known antibacterial properties and which could synergistically act with silver and spinel. 相似文献
43.
Maria Francesca Sfondrini Simone Gallo Benedetta Turcato Mona A. Montasser Nehal Fouad Albelasy Pekka K. Vallittu Paola Gandini Andrea Scribante 《Materials》2021,14(6)
This study aims to assess the efficacy of a universal adhesive (Scotchbond Universal, 3M ESPE) (SB) in total-etch mode, compared to a traditional orthodontic primer (Transbond XT Primer, 3M ESPE) (XT Primer), to perform bonding of orthodontic fixed retainers along with the Transbond XT Light Cure Adhesive Paste (3M ESPE). For the in vitro study, a round section wire (Ortosmail Krugg) was bonded using XT Primer for 20 bovine incisors (Group 1) and SB for other 20 (Group 2). Samples were debonded in a universal testing machine applying a tangential force to specimens (crosshead speed of 1 millimeter per minute). Shear bond strength (SBS) and adhesive remnant index (ARI) scores were calculated. For the in vivo study, 100 patients needing upper and lower canine-to-canine fixed retainers after orthodontic treatment were randomly assigned to two groups of 50 participants each, i.e., group 1 (retainer bonding with XT Primer) and group 2 (retainer bonding with SB). Over two years, examinations were carried out monthly, and detachments were registered by considering the teeth and arches affected. In vitro, no statistically significant differences in SBS and ARI scores were demonstrated between the two groups, both showing a mean bond strength of about 12 MPa and major frequency of ARI “2” (>50% remnant adhesive on the enamel). Conversely, a significantly lower failure rate over 2 years was assessed clinically for group 2 in both arches. Independently of the adhesive and arch, incisors reported a significantly higher failure rate than canines. Scotchbond Universal used in total-etch mode could be a valid alternative to the traditional orthodontic Transbond XT Primer. 相似文献
44.
45.
Risk factors of peptic ulcer in 4943 inpatients 总被引:1,自引:0,他引:1
46.
Luca Morelli Alessandra Perutelli Matteo Palmeri Simone Guadagni Maria Donatella Mariniello Gregorio Di Franco Vito Cela Benedetta Brundu Maria Giovanna Salerno Giulio Di Candio Franco Mosca 《International journal of colorectal disease》2016,31(3):643-652
Purpose
Sexual and urinary dysfunctions are complications in radical treatment of deep infiltrating endometriosis (DIE) with colorectal involvement. The aim of this article is to report the preliminary results of our single-institution experience with robotic treatment of DIE, evaluating intraoperative and postoperative surgical outcomes and focusing on the impact of this surgical approach on autonomic functions such as urogenital preservation and sexual well-being.Methods
From January 2011 through December 2013, a case series of 10 patients underwent robotic radical treatment of DIE with colorectal resection using the da Vinci System. Surgical data were evaluated, together with perioperative urinary and sexual function as assessed by means of self-administered validated questionnaires.Results
None of the patients reported significant postoperative complications. Questionnaires concerning sexual well-being, urinary function, and impact of symptoms on quality of life demonstrated a slight worsening of all parameters 1 month after surgery, while data were comparable to the preoperative period 1 year after surgery. Dyspareunia was the only exception, as it was significantly improved 12 months after surgery.Conclusions
Robot-assisted surgery seems to be advantageous in highly complicated procedures where extensive dissection and proper anatomy re-establishment is required, as in DIE with colorectal involvement. Our preliminary results show that robot-assisted surgery could be associated with a low risk of complications and provide good preservation of urinary function and sexual well-being.47.
48.
Vascular endothelial growth factor, left ventricular dysfunction and mortality in hemodialysis patients 总被引:1,自引:0,他引:1
Mallamaci F Benedetto FA Tripepi G Cutrupi S Pizzini P Stancanelli B Seminara G Bonanno G Rapisarda F Fatuzzo P Malatino LS Zoccali C 《Journal of hypertension》2008,26(9):1875-1882
OBJECTIVES: Vascular endothelial growth factor induces nitric oxide-dependent angiogenic effects and participates in the inflammatory response. This cytokine is over-expressed in the myocardium in experimental models of pressure overload and renal mass ablation, and vascular endothelial growth factor is increased in end-stage renal disease. We investigated the relationship between vascular endothelial growth factor, left ventricular function (by midwall fractional shortening) and mortality in a prospective cohort study in 228 hemodialysis patients. RESULTS: Serum vascular endothelial growth factor concentration was associated directly with interleukin-6 and tumor necrosis factor-alpha (P < 0.01) and inversely with albumin (P = 0.007) but was independent of the endogenous inhibitor of nitric oxide synthesis, asymmetric dimethylarginine. Vascular endothelial growth factor was inversely related with midwall fractional shortening (P = 0.002) and predicted mortality (P = 0.02). In multivariate analyses testing the involvement of this angiogenic cytokine in left ventricular dysfunction and death, these links remained substantially unmodified after adjustment for Framingham risk factors, risk factors peculiar to end-stage renal disease (Hb, Ca, P) and previous cardiovascular complications. However, these links became weaker and not significant when biomarkers of inflammation and asymmetric dimethylarginine were sequentially introduced into the multivariate models. In crude and adjusted analyses, left ventricular function was lowest in patients who displayed both high vascular endothelial growth factor and high asymmetric dimethylarginine, intermediate in patients with either high vascular endothelial growth factor or high asymmetric dimethylarginine and highest in those with low asymmetric dimethylarginine and low vascular endothelial growth factor (P = 0.001). CONCLUSION: Vascular endothelial growth factor is associated with left ventricular systolic dysfunction and mortality in hemodialysis patients. Vascular endothelial growth factor appears to be in the pathway whereby inflammation and nitric oxide inhibition lead to cardiomyopathy and death in hemodialysis patients. 相似文献
49.
Lugoboni F Migliozzi S Mezzelani P Pajusco B Ceravolo R Quaglio G 《Scandinavian journal of infectious diseases》2004,36(2):131-133
In the Western world, the population at the highest risk of HBV infection is probably that of illicit drug users (DUs). Since 1985, 1 Public Health Centre for Drug Users (PHCDU), in north-eastern Italy, has been asking all heroin DUs, whether in treatment or not, to undergo screening for HIV, HBV and, since 1989, for HCV infection. Since 1988 the Centre has proposed HBV vaccination to all patients who were negative for all HBV markers. From 1985 to 2001 895 heroin DUs were screened, 726 males and 169 females. 442 (49.4%) were negative to HBV markers at the first control and 72.4% received at least 1 dose of the vaccine. 320 DUs were vaccinated and a total of 995 doses of recombinant vaccine were administered. The anti-HBc antibody appeared in 2 vaccinated patients out of 258 DUs undergoing controls, while 13 seroconversions for anti-HBc occurred in 45 DUs who had refused to be vaccinated. On the basis of these results, HBV vaccination of DUs can be strongly recommended. Vaccination showed a good adherence in a population difficult to treat and can have a leading role in reducing HBV infection in DUs and their contacts. 相似文献
50.
We report the sixth occurrence of Hb Belfast [beta15(A12)Trp-->Arg], a mild, unstable beta chain variant, in a large family wherein nine subjects were affected. DNA analysis showed a TUG-->AGG mutation at codon 15 of the beta-globin gene, confirming a Trp-->Arg amino acid substitution. The oxygen affinity of the isolated variant was increased. The clinical phenotype is silent or very mild, the only clinical finding being an intermittent moderate jaundice. 相似文献