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71.
A total of 84 European hares collected from eleven Serbian regions investigated upon cadmium (Cd) and zinc (Zn) presence. Strong statistically significant correlations between Cd concentrations in kidney and liver were registered in animals older than 12 months. Significant differences between Zn concentrations in liver in comparison to kidney were found within every single age group with exception of the oldest. Negative correlation (Ps—Pearson’s correlation) between Zn and Cd concentrations were found in liver samples within the age group of 12 months (Ps = ?0.67, p = 0.004).  相似文献   
72.
Predicting human safety risks of novel xenobiotics remains a major challenge, partly due to the limited availability of human cells to evaluate tissue-specific toxicity. Recent progress in the production of human induced pluripotent stem cells (hiPSCs) may fill this gap. hiPSCs can be continuously expanded in culture in an undifferentiated state and then differentiated to form most cell types. Thus, it is becoming technically feasible to generate large quantities of human cell types and, in combination with relatively new detection methods, to develop higher-throughput in vitro assays that quantify tissue-specific biological properties. Indeed, the first wave of large scale hiSC-differentiated cell types including patient-derived hiPSCS are now commercially available. However, significant improvements in hiPSC production and differentiation processes are required before cell-based toxicity assays that accurately reflect mature tissue phenotypes can be delivered and implemented in a cost-effective manner. In this review, we discuss the promising alignment of hiPSCs and recently emerging technologies to quantify tissue-specific functions. We emphasize liver, cardiovascular, and CNS safety risks and highlight limitations that must be overcome before routine screening for toxicity pathways in hiSC-derived cells can be established.  相似文献   
73.
An albumin-simian virus 40 (SV40) large T-antigen (T-Ag) transgenic model and a chemically induced model of multistage hepatocarcinogenesis were created in our laboratory to study the molecular mechanisms involved in the genesis and progression of neoplasia in the rat liver. In the study presented here, these two models of rat hepatocarcinogenesis were used to perform a comparative mutational analysis of three tumor suppressor genes involved in hepatic neoplastic growth. By using polymerase chain reaction-single strand conformation polymorphism analysis and sequencing, exons 5-8 of the p53 tumor suppressor gene and a region between nt 4325 and 4479 of the rat mannose 6-phosphate/insulin-like growth factor 2 receptor (M6p/Igf2r) coding sequence were screened. The latter is homologous to the human M6P/IGF2r coding sequence which is mutated in human hepatocellular carcinoma. A complete single strand conformation polymorphism analysis of the entire coding region of the rat adenomatous polyposis coli (Apc) gene was also performed for the first time in rat tumorigenic samples. Twenty-six chemically induced rat hepatocellular carcinomas, 21 neoplasms from the livers of SV40 T-Ag animals, and five immortalized hepatic cell lines from the transgenic rats were evaluated. None of the hepatic tumors exhibited mutations in the regions analyzed. The albumin-SV40 T-Ag transgenic cell line L-60, derived from normal hepatic tissue, had two mutations in contiguous codons of exon 5 of the p53 gene: a GGT --> GTT missense transversion in codon 183 and a silent mutation in codon 184. The transversion, which may affect the DNA binding domain of the p53 protein, probably originated during cell culture and may have been positively selected because it gave a growth advantage to the mutated cells. The studied region of the M6p/Igf2r gene was not found to be mutated in these two models of rat hepatocarcinogenesis. Although M6p/Igf2r, Apc, and p53 have been shown to be mutated in a variety of human hepatic proliferative diseases, our results indicate that aberrations in these genes may not be necessary for liver carcinogenesis in the rat.  相似文献   
74.
    
Objectives:   Risk factors for surgical site infection (SSI) following urologic dirty operations have not been clearly identified. This study was conducted to describe incidence, potential risk factors and common causative pathogens of the SSI in such operations.
Methods:   Medical records of patients who had undergone simple nephrectomy or lumbotomy for suppurative renal infection at our institutions from 1999 to 2006 were retrospectively evaluated. The following data were retrieved: presence of SSI, demographic data, laboratory findings, comorbidities, microbiological data, type of renal suppuration, type of urological surgery and antibiotic regimen. Risk factors for SSI were evaluated using the multiple logistic regression model.
Results:   Sixty-five patients (mean age 55.6 ± 13.1 years) were eligible for data analysis. In 20 of them (30.8%) a SSI was identified. The most common isolated pathogens were gram-negative bacteria. At univariate logistic regression analysis risk factors significantly associated with SSI included: presence of emphysematous infection, hypoalbuminemia, number of predisposing conditions, emergency operations, isolation of Enterobacteriaceae, positive pus culture. The use of trimethoprim/sulfamethoxazole was associated with a decreased risk for SSI. Multiple logistic model identified only the emergency operations and isolated Enterobacteriaceae as independent predictors of SSI (odds ratio [OR] = 11.1) (95% confidence interval [CI] = 3.0–40.8) and OR = 3.9 (1.0–14.8), respectively.
Conclusions:   Patients with suppurative renal infections are submitted to life-saving emergency surgery. Urological surgeons should keep in mind that this carries a high risk for subsequent SSI. Effective preventive measures in these circumstance cannot be identified. Further research in this area is necessary to clarify this issue.  相似文献   
75.
    
Recent studies show a high prevalence of traumatic events in samples of patients with a substance use disorder. In the present study, the lifetime exposure to potentially traumatic events (PTEs) was estimated in a sample of 458 patients recruited at 17 randomly chosen alcohol-dependence treatment units in the public healthcare sector in Poland. Eighty percent of the patients reported a history of at least one potentially traumatic event. Sixty percent of them reported experiencing more than one probable trauma. However, only the patients who experienced physical assault reported worse clinical severity in posttraumatic stress and alcohol-use related symptomatology. The findings confirm the importance of trauma assessment in alcohol-dependent patients and the inclusion of trauma-related issues in the treatment of alcohol dependence.  相似文献   
76.
    
Objectives: To report a single‐center experience with robot‐assisted pyeloplasty. Methods: Medical records of 100 consecutive robot‐assisted pyeloplasty cases carried out between May 2004 and August 2010 were retrospectively reviewed, and major perioperative parameters were recorded. Patients underwent functional (renal scan) and/or anatomical (ultrasound or computerized tomoghraphy) imaging at 6 months. Results: The mean patient age was 39.8 years. A total of 12 patients underwent prior attempts at repair. Ureteral stents were placed in all patients except one, and closed‐suction drains were placed in 59 patients. There were two intraoperative complications and two postoperative complications requiring surgical intervention. One patient with a complex prior surgical history developed a urine leak that was managed with prolonged drainage. A total of 42 patients were discharged on postoperative day 1, and 44 were discharged on postoperative day 2. Mean length of follow up was 22.8 months. The operative success rate was 96%. Conclusions: The majority of patients undergoing robot‐assisted pyeloplasty can expect a short hospitalization with minimal morbidity. The operative success rate is high, even in patients with prior attempts at repair. Complication rates including urine leaks are quite low, and routine placement of a closed‐suction drain is likely to be unnecessary.  相似文献   
77.
    
Background and purpose — There is no consensus about the outcome of simultaneous vs. staged bilateral total knee arthroplasty (TKA). We examined this issue by analyzing 238,373 patients.

Patients and methods — Demographic, clinical, and outcome data were evaluated for TKA patients (unilateral: 206,771; simultaneous bilateral: 6,349; staged bilateral: 25,253) from the Canadian Hospital Morbidity Database for fiscal years 2006–2007 to 2012–2013. Outcomes were adjusted for age, sex, comorbidities, and hospital TKA volume.

Results — Simultaneous bilateral TKA patients were younger than staged bilateral TKA patients (median 64 years vs. 66 years), were more likely to be male (41% vs. 39%), and had a lower frequency of having ≥1 comorbid condition (2.9% vs. 4.2%). They also had a higher frequency of blood transfusions (41% vs. 19%), a shorter median length of stay (6 days vs. 8 days), a higher frequency of transfer to a rehabilitation facility (46% vs. 9%), and a lower frequency of knee infection (0.5% vs. 0.9%) than staged bilateral TKA patients, but they had higher rate of cardiac complications within 90 days (2.0% vs. 1.7%). Simultaneous patients had higher in-hospital mortality compared to the second TKA in staged patients (0.16% vs. 0.06%), but they had similar rates of in-hospital mortality compared to unilateral patients (0.16% vs. 0.14%). The cumulative 3-year revision rate was highest in the unilateral group (2.3%), but it was similar in the staged and simultaneous bilateral groups (1.4%).

Interpretation — We found important differences between the outcomes of simultaneous and staged bilateral TKA. Further clarification of outcomes would be best determined in an adequately powered randomized trial, which would remove the selection bias inherent in this retrospective study design.  相似文献   
78.
    
Objective: To analyse the incidence, clinical presentation, and outcome of heart insufficiency in patients with chronic arteriovenous fistulas (AVF). Methodology: From 1991 to 2000 we treated 49 patients with traumatic AVF. The present study included 19 patients with AVF present for 6 months or longer, as it was presumed that these AVF will have an impact on cardiac overload. There were 16 male and three female patients with a mean age of 36 years (17–59). The time from injury to admission varied from 6 months to 33 years. Cardiological examination checked for dyspnoea and palpitation. ECG, chest X‐ray and ECHO‐cardiography were also performed. All AVF were deleted, magistral vessels reconstructed, non‐magistral obliterated, either surgically or by percutaneous embolization. Results: Mean follow up was 44.2 months (3–93). Serious heart insufficiency was seen in two patients only, with AVF in the subclavial vessels. Both suffered from serious heart disease prior to the therapeutic procedures that resulted in iatrogenic AVF, so it was difficult to connect heart insufficiency to the AVF alone. Despite surgical closure of AVF and intensive medical treatment, signs of heart insufficiency remained in both patients. Signs of cardiac overload were seen in six patients with long‐standing AVF in major vessels. Except for one patient who refused surgical closure of femoral AVF, the remaining five were symptom free for cardiac overload during the follow‐up period. Conclusion: In our series, heart insufficiency was an infrequent complication in long‐standing AVF, even when major vessels were involved.  相似文献   
79.
Sympathetic reflex dystrophy of the upper extremity is among the most serious complications of trauma injuries. The aim of this paper was to assess the effectiveness of mobilization treatment, augmented by cryogenic temperatures of post trauma SRD of the upper extremity. The material comprised 113 patients treated at the Orthopedic Outpatient Clinic of the J. Babiński Hospital in Breslau during the years 1987-1995. All patients underwent conservative treatment because of post trauma SRD. The effectiveness of cryo-therapy was based on pre- and post-therapy ROM examination. These results were compared to the ROM of the healthy extremity and the degree of ROM limitation was hence calculated. Limitation of ROM was found in all joints of the upper extremity regardless to the stage of the disease. The greatest limitations were found in the joints directly adjacent to the area were the disease was most pronounced. The applied therapy in these cases was found to increase ROM in all patients, with the greatest increase of ROM during stage I and II of the disease.  相似文献   
80.
BACKGROUND: The aim of this study was to examine prothrombogenic factors and antioxidative defense in obese children and adolescents with pre-metabolic and metabolic syndrome, and to analyze insulin secretion and resistance, early glycoregulation disorders and lipid status. METHODS: Insulin sensitivity was determined using the homeostasis model assessment for insulin resistance (HOMA-IR), while insulin secretion was determined using the homeostasis model assessment beta (HOMA-beta). Prothrombogenic factors analyzed were plasma plasminogen activator inhibitor-1 (PAI-1) and fibrinogen. Superoxide dismutase and glutathione peroxidase were measured as markers of antioxidative defense. RESULTS: Patients with metabolic syndrome were characterized with increased body mass index (BMI), waist circumference, and HOMA-IR and HOMA-beta levels, and all had increased blood pressure and triglyceride levels, low high-density lipoprotein cholesterol levels, increased PAI-1 levels and reduced antioxidative defense levels. Patients with pre-metabolic syndrome had higher levels of basal and mean insulinemia during an oral glucose tolerance test, higher levels of HOMA-beta and lower levels of antioxidative defense compared to patients with metabolic syndrome. CONCLUSIONS: Negative correlations between antioxidative defense parameters and BMI, abdominal obesity, insulin secretion, systolic blood pressure and atherogenic lipid factors, as well as correlations between PAI-1 and insulin resistance and basal glycemia in the metabolic syndrome group contribute to accelerated atherosclerosis. Positive correlations between PAI-1 and waist circumference and BMI, and negative correlations between BMI and antioxidative defense in the pre-metabolic syndrome patients show that this early stage preceding the metabolic syndrome is also characterized by atherosclerotic complication risks and evident hyperinsulinism and insulin resistance.  相似文献   
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