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51.

Introduction

The objective of this study was to show the morphologic characteristics of allograft renal biopsies in renal transplant patients with stable renal function, which can potentially be early markers of allograft dysfunction, after 5 years of follow-up.

Methods

Forty-nine renal transplant patients with stable renal function were submitted to renal biopsies and simultaneous measurement of serum creatinine (Cr). Histology was evaluated using Banff scores, determination of interstitial fibrosis by Sirius red staining and immunohistochemical study of proximal tubule and interstitial compartment (using cytokeratin, vimentin, and myofibroblasts as markers). Biopsies were evaluated according to the presence or absence of the epitheliomesenchymal transition (EMT). The interstitial presence of myofibroblasts and tubular presence of vimentin was also analyzed simultaneously. Renal function was measured over the follow-up period to estimate the reduction of graft function.

Results

Median posttransplant time at enrollment was 105 days. Patients were followed for 64.3 ± 8.5 months. The mean Cr at biopsy time was 1.44 ± 0.33 mg/dL, and after the follow-up it was 1.29 ± 0.27 mg/dL. Nine patients (19%) had a reduction of their graft function. Eleven biopsies (22%) had tubulointerstitial alterations according to Banff score. Seventeen biopsies (34%) presented EMT. Fifteen biopsies (32%) had high interstitial expression of myofibroblasts and tubular vimentin. Using Cox multivariate analysis, HLA and high expression of interstitial myofibroblasts and tubular vimentin were associated with reduction of graft function, yielding a risk of 3.3 (P = .033) and 9.8 (P = .015), respectively.

Conclusion

Fibrogenesis mechanisms occur very early after transplantation and are risk factors for long-term renal function deterioration.  相似文献   
52.
Objective: To evaluate the influence of the local prenatal surveillance of twin pregnancies in the obstetrical results.

Methods: A prospective cohort study of multiple pregnancies delivered over a period of 16 years in a tertiary centre was conducted. In this study 861 twin pregnancies were included. They were compared for obstetric complications, gestational age at delivery, mode of delivery and birthweight, according to the place of the surveillance.

Results: Of the 861 cases examined, the following obstetric complications were significantly different: metrorrhagia (p?=?0.039), infections (p?p?=?0.007), PROMPT (p?p?=?0.024). The mode of delivery was similar but occurred mostly ≤32 weeks (p?p?Conclusion: Our results demonstrate the crucial importance of prenatal surveillance be carried in a differentiated referral centers with specific/strict protocols or the urgent implementation of same protocols in all other places of surveillance, since this straight surveillance greatly reduces the occurrence of prenatal complications, mainly PROMPT, PTD.  相似文献   
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Background:Although non-ischemic troponin elevation is frequently seen in patients admitted to the emergency department (ED), consensus regarding its management is lacking.Objectives:This study aimed to characterize patients admitted to the ED with non-ischemic troponin elevation and to identify potential mortality predictors in this population.Methods:This retrospective observational study included ED patients with a positive troponin test result between June and July of 2015. Patients with a clinical diagnosis of acute coronary syndrome (ACS) were excluded. Data on patient demographics and clinical and laboratory variables were extracted from medical records. Follow-up data were obtained for 16 months or until death occurred. The statistical significance level was 5%.Results:Troponin elevation without ACS was found in 153 ED patients. The median (IQR) patient age was 78 (19) years, 80 (52.3%) were female and 59(38.6%) died during follow-up. The median (IQR) follow-up period was 477(316) days. Survivors were significantly younger 76 (24) vs. 84 (13) years; p=0.004) and featured a higher proportion of isolated troponin elevation (without creatine kinase or myoglobin elevation) in two consecutive evaluations: 48 (53.9%) vs. 8 (17.4%), p<0.001. Survivors also presented a lower rate of antiplatelet treatment and same-day hospitalization. In the multivariate logistic regression with adjustment for significant variables in the univariate analysis, isolated troponin elevation in two consecutive evaluations showed a hazard ratio= 0.43 (95%CI 0.17–0.96, p=0.039); hospitalization, previous antiplatelet treatment and age remained independently associated with mortality.Conclusions:Isolated troponin elevation in two consecutive measurements was a strong predictor of survival in ED patients with troponin elevation but without ACS.  相似文献   
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Controversy exists concerning the degree of microbial contamination associated with the us of rigid lumened medical devices, the efficacy of standard cleaning techniques used to remove pathogenic microorganisms from lumen channels, and whether patients are placed at risk of cross infection because of microbial contamination. In this study the level and types of microorganisms found on rigid lumened medical devices before and after cleaning in a hospital environment were investigated. The bioburden level after clinical use was found to be relatively low, ranging from 101 to 104 colony forming units (CFU) per device. After the instruments were cleaned, none of the devices studied contained bioburden levels greater than 104 CFU and 83% had bioburden levels less than or equal to 102 CFU. The bioburden present before cleaning was comprised of organisms derived from the handling of the device, from the hospital environment, and from the patient. The bioburden present after cleaning was comprised of organisms typically derived from the handling of the device and from the hospital environment. The level of bioburden per device was also related to the anatomic site where the device was used, with lower numbers of organisms found on devices exposed to sterile body sites and the respiratory tract.  相似文献   
57.
A detailed investigation to understand the mechanism of the resist action at a fundamental level is essential for future Extreme Ultraviolet Lithography (EUVL) resists. The photodynamics study of a newly developed hybrid nonchemically amplified 2.15%-MAPDSA–MAPDST resist using synchrotron radiation excitation at 103.5 eV (12 nm) is presented. Antimony was incorporated in the resist as a heavy metal absorption center in the form of antimonate (2.15%). The results showed the fast decomposition rate of the radiation sensitive sulfonium triflate. HR-XPS and sulfur L-NEXAFS spectra of the copolymer films revealed that after irradiation the Ar–S+–(CH3)2 sulfonium group bonded to the phenyl ring resisted the EUV excitation. Those results confirmed the polarity switching mechanism from hydrophilic sulfonium triflates to hydrophobic aromatic sulfides obtained in previous results. The inorganic component SbF6 included in the resist formulations as an EUV absorption enhancer was particularly illustrative of the photofragmentation process. F 1s and O 1s HR-XPS spectra showed that fluorine remains linked to the antimony, even after 15 min of irradiation. A change of the antimony oxidation state was also observed with an increase in irradiation time. The presence of the heavy metal may control the high energy deposited on the resist which finally led to very well resolved 20 nm isolated line patterns by EUVL. The 10 times improved sensitivity compared with previous poly-MAPDST resists studied in the past showed the potential of this class of hybrid resists for next generation semiconductor industry applications.

Understanding the EUV photofragmentation mechanism in a highly sensitive hybrid n-CAR containing SbF6 as an absorption enhancer.  相似文献   
58.
The aims of this pilot study were to verify which muscle strength tests better explain bone mineral content (BMC) of the femoral neck and lumbar spine and to develop predictive equations to estimate femoral neck and lumbar spine BMC. Twenty-nine subjects aged 56–76 years old (12 women and 17 men) participated in the study. Femoral neck and lumbar spine BMC was evaluated by Dual X-ray absorptiometry (DXA). Muscle strength measurements included maximal isometric voluntary contractions of knee extensors and flexors, vertical jump, 5-repetition maximum of the leg press (5-RMLP) and seated leg curl (5-RMLC), and handgrip strength. Women presented a moderate to strong correlation between femoral neck BMC and 5-RMLP (r = 0.819), 5-RMLC (r = 0.879), knee extensors peak torque (r = 0.699), and handgrip strength (r = 0.663), as well as between lumbar spine BMC and the 5-RMLP test (r = 0.845) and manual grip strength (r = 0.699). For females, the 5-RMLP and 5-RMLC tests most fully explained femoral neck BMC (R2 = 0.859) and the 5-RMLP test and body mass explained lumbar spine density (R2 = 0.757) for females. Men did not present correlations between BMC and strength variables. For females, the 5-RMLP and 5-RMLC variables explained the variations of femoral neck BMC, while 5-RMLP and body mass explained lumbar spine BMC. Future studies should evaluate a larger sample size and prioritize the strength tests with a greater predictive capacity.  相似文献   
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Sport Sciences for Health - To investigate the hemodynamic responses, especially HPE following different resistance exercises RE protocols in young adult subjects. Eighty-nine men...  相似文献   
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