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31.
Ecotoxicology - This study aimed to investigate the mode of action of cadmium (Cd) toxicity at cell level, especially at early stages of plant exposure. Tomato seedlings were cultivated in growth...  相似文献   
32.
Two cases of swallowing of foreign material related to dental implants during dental practice are described. A conservative approach by clinical-radiographic follow-up was performed in both cases; however, one of the patients required colonoscopy under general anesthesia for the removal of the impacted foreign body from the intestinal region. These complications not only have associated economic cost but also carry the risk of malpractice litigation against the professional; thus, the surgeon was responsible for all the costs of hospital and surgery management of this case. Details of the clinical signs, radiographic examinations, type of treatment, and follow-up are presented.  相似文献   
33.

Background  

Glioblastoma remains one of the most devastating human malignancies, and despite therapeutic advances, there are no drugs that significantly improve the patient survival. Altered expression of the Aurora kinases was found in different malignancies, and their inhibition has been studied in cancer therapy. In this study, we analyzed the expression of Aurora A and Aurora B in glioblastoma samples and also analyzed whether the effects of Aurora kinase inhibition were associated with temozolomide or not on cell lines and primary cultures of glioblastoma.  相似文献   
34.
35.

Introduction

The high mortality and morbidity associated with resection for oesophagogastric malignancy has resulted in a conservative approach to the postoperative management of this patient group. In August 2009 we introduced an enhanced recovery after surgery (ERAS) pathway tailored to patients undergoing resection for oesophagogastric malignancy. We aimed to assess the impact of this change in practice on standard clinical outcomes.

Methods

Two cohorts were studied of patients undergoing resection for oesophagogastric malignancy before (August 2008 – July 2009) and after (August 2009 – July 2010) the implementation of the ERAS pathway. Data were collected on demographics, interventions, length of stay, morbidity and in-hospital mortality.

Results

There were 53 and 55 oesophagogastric resections undertaken respectively for malignant disease in each of the study periods. The median length of stay for both gastric and oesophageal resection decreased from 15 to 11 days (Mann– Whitney U, p<0.001) following implementation of the ERAS pathway. There was no significant increase in morbidity (gastric resection 23.1% vs 5.3% and oesophageal resection 25.9% vs 16.7%) or mortality (gastric resection no deaths and oesophageal resection 1.8% vs 3.6%) associated with the changes. There was a significant decrease in the number of oral contrast studies used following oesophageal resection, with a reduction from 21 (77.8%) in 2008–2009 to 6 (16.7%) in 2009–2010 (chi-squared test, p<0.0001).

Conclusions

The introduction of an enhanced recovery programme following oesophagogastric surgery resulted in a significant decrease in length of median patient stay in hospital without a significant increase in associated morbidity and mortality.  相似文献   
36.

Introduction

In vitro hydrodynamic characterization of prosthetic heart valves provides important information regarding their operation, especially if performed by noninvasive techniques of anemometry. Once velocity profiles for each valve are provided, it is possible to compare them in terms of hydrodynamic performance. In this first experimental study using laser doppler anemometry with mechanical valves, the simulations were performed at a steady flow workbench.

Objective

To compare unidimensional velocity profiles at the central plane of two bi-leaflet aortic prosthesis from St. Jude (AGN 21 - 751 and 21 AJ - 501 models) exposed to a steady flow regime, on four distinct sections, three downstream and one upstream.

Methods

To provide similar conditions for the flow through each prosthesis by a steady flow workbench (water, flow rate of 17L/min. ) and, for the same sections and sweeps, to obtain the velocity profiles of each heart valve by unidimensional measurements.

Results

It was found that higher velocities correspond to the prosthesis with smaller inner diameter and instabilities of flow are larger as the section of interest is closer to the valve. Regions of recirculation, stagnation of flow, low pressure, and flow peak velocities were also found.

Conclusions

Considering the hydrodynamic aspect and for every section measured, it could be concluded that the prosthesis model AGN 21 - 751 (RegentTM) is superior to the 21 AJ - 501 model (Master Series). Based on the results, future studies can choose to focus on specific regions of the these valves.  相似文献   
37.
ObjectiveCompare the anti-T. gondii IgG titer between HIV-1 infected and non HIV-1 infected pregnant women and report three cases of congenital toxoplasmosis resulting from reactivation of infection during pregnancy of HIV-1 infected women.MethodsThis study was conducted among 2,270 pregnant women with chronic Toxoplasma gondii infection (absence of IgM and presence of IgG), including 82 HIV-1 infected and 2,188 non-infected women.ResultsThe average anti-T. gondii IgG titer was 127 for the 2,188 non-HIV-1 infected women, and 227 for the 82 HIV-1-infected women (p = 0,007). These results suggested that higher anti-T. gondii IgG titers in HIV-1-infected pregnant women may not be indicative of an elevated risk for fetal infection. In this study three cases of congenital toxoplasmosis that resulted from infection reactivation during pregnancy of HIV-1-infected women were manifested by fetal death, symptomatic infection, and infant without symptoms, respectively. In two of these women, a ten-fold increase in IgG levels above used cutoff was observed (2,320 UI/mL and 3,613 UI/mL, respectively). In the third pregnant women anti-T. gondii IgG titers during pregnancy did not rise despite the occurrence of congenital toxoplasmosis (204; 198; 172 UI/mL).ConclusionsCongenital toxoplasmosis resulting reactivation of infection during pregnancy in the studied group leads us to believe that it is a public health problem, especially in our population, in which seroprevalence of T. gondii infections is high. These findings also suggest that special attention is necessary during pregnancy, because the serologic diagnosis may not be indicative of toxoplasmosis reactivation.  相似文献   
38.

Purpose

Malnutrition is a strong predictor of mortality in hemodialysis patients. Several scoring systems for evaluating nutritional status have been proposed. However, they rely on different sets of anthropometric and laboratory markers to make a diagnosis of malnutrition and assess its impact on prognosis. To validate them, nutritional scores should be compared with clinical outcomes. Thus, the purpose of this study was to assess malnutrition by three different nutrition scoring systems and determine which best predicts mortality in hemodialysis patients.

Methods

This prospective study included 106 adult chronic hemodialysis patients. Their mean age was 56.3 ± 14.9 years and mean body mass index 24.8 (21.8–28.9); 52 % were men and they had been on dialysis for 24 (5–55) months. Nutritional status was classified according to the diagnostic systems proposed by Wolfson et al. (Am J Clin Nutr 39(4):547–555, 1984), International Society of Renal Nutrition and Metabolism (ISRNM) (Fouque et al. in Kidney Int 73(4):391–398, 2008), and Beberashvili et al. (Nephrol Dial Transplant 25(8):2662–2671, 2010). During about 2 years of follow-up, mortality was assessed by Kaplan–Meier curves, log-rank, and Cox’s models adjusted for diabetes, sex, C-reactive protein, time on dialysis, age, and fractional urea clearance.

Results

Twenty-three deaths (21.5 %) occurred during the study period. According to the systems of Wolfson, Beberashvili, and the ISRNM, 54, 32, and 20 % of patients, respectively, had malnutrition. Both univariate and multivariate analyses showed that the ISRNM system was the only one that predicted poorer survival (fourfold higher death risk) in malnourished patients.

Conclusions

The scoring system proposed by the ISRNM most accurately identifies patients at higher risk of death.  相似文献   
39.
40.
The present study aimed to investigate the role of angiotensin II (Ang II) on sodium appetite in rats subjected to a normal or a low‐sodium diet (1% or > 0.1% NaCl) for 4 days. During sodium restriction, a reduction in water intake, urinary volume and sodium excretion was observed. After a low‐sodium diet, we observed decreased plasma protein concentrations and haematocrit associated with a slight reduction in arterial pressure, without any significant changes in heart rate, natraemia, corticotrophin‐releasing hormone mRNA expression in the paraventricular nucleus and corticosterone levels. After providing hypertonic saline, there was an increase in saline intake followed by a small increase in water intake, resulting in an enhanced saline intake ratio and the recovery of arterial pressure. Sodium deprivation increased plasma but not brain Ang I and II concentrations. A low‐sodium diet increased kidney renin and liver angiotensinogen mRNA levels but not lung angiotensin‐converting enzyme mRNA expression. Moreover, Ang II type 1a receptor mRNA expression was increased in the subfornical organ and the dorsal raphe nucleus and decreased in the medial preoptic nuclei, without changes in the paraventricular nucleus and the nucleus of solitary tract after a low‐sodium diet. Blockade of AT1 receptors or brain Ang II synthesis led to a reduction in sodium intake after a low‐sodium diet. Intracerebroventricular injection of Ang II led to a similar increase in sodium and water intake in the control and low‐sodium diet groups. In conclusion, the results of the present study suggest that Ang II is involved in the increased sodium appetite after a low‐sodium diet.  相似文献   
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