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61.
Background and objectives: Concern about primary fistula failure may contribute to the underuse of arteriovenous fistula. The objective of this study was to investigate the baseline clinical parameters associated with primary fistula success.Design, setting, participants, & measurements: Consecutive incident patients who commenced dialysis during a 28-mo period in a regional renal program were studied. Data on patient-related variables and on surgical approach (e.g., whether the surgeons routinely assess vessel size during the operation) were collected. Primary fistula success was defined as an arteriovenous fistula that was able to afford successful dialysis for 3 h with blood pump speed of ≥300 ml/min for three consecutive sessions.Results: A total of 205 (69%) patients had an AVF attempted as their first vascular access. The overall primary success rate was 64% and was similar for radiocephalic and brachiocephalic fistula. Logistic regression was done separately for patients with the two types of fistula because of the presence of statistical interaction. For radiocephalic fistula, male gender was the only parameter associated with primary fistula success (odds ratio 3.57; P = 0.01). The presence of comorbidity was not significantly associated with primary fistula failure.Conclusions: Despite significant patient comorbidity, there was a high primary fistula success rate among this incident hemodialysis cohort. Given that vessel size may be the ultimate determinant of fistula success, if surgeons assess vessel size perioperatively, then the presence of significant comorbidity might not preclude arteriovenous fistula from being attempted as the initial access.Given the well-documented advantages of arteriovenous fistula (AVF) over arteriovenous graft and central venous catheter (CVC), the current Kidney Disease Outcomes Quality Initiative (K/DOQI) guidelines suggest that AVF should be attempted as the initial vascular access in at least 50% of incident patients and that at least 40% of prevalent hemodialysis (HD) patients should undergo dialysis with an AVF (15). Despite these recommendations, it is clear that AVF are underused in many centers in North America, especially when compared with European centers (6,7). Recent data suggest that only 32% of prevalent US HD patients undergo dialysis with an AVF (8). In Canada, AVF are used by 53% of prevalent and only 26% of incident HD patients (7).One of the fears that may reduce the use of AVF is the high primary fistula failure rate (i.e., failure of AVF to mature) (9). Identifying risk factors that contribute to primary fistula failure may help clinicians and patients make an informed decision as to for whom to attempt an AVF. Only a few studies have prospectively examined the risk factors associated with primary fistula failure, which has been reported in 20 to 50% of patients (912).Most studies that have evaluated factors that are associated with primary fistula failure have typically used a retrospective design. For instance, Miller et al. (10) reported higher primary fistula failure rate in older and female patients with diabetes, although small numbers and a highly selected patient population limit the generalizability of these results. Feldman et al. (13) published data from a larger cohort (348 patients), reporting a primary success rate of 54%. Preexisting cerebrovascular disease, older age, and commencement of dialysis before access creation were noted to be associated with higher primary fistula failure in their study. Ravani et al. (11) noted that cardiovascular disease and late referral to nephrologists were associated with lower primary AVF success in patients from northern Italy.More recently, Lok et al. (14) studied a cohort of 422 HD patients who were undergoing their first AVF placement to identify preoperative clinical characteristics that are predictive of fistula failure to mature and to use this information to develop a prediction rule to estimate the risk for fistula failure to mature. This prediction rule was validated in an external data set from five North American centers. Age, peripheral vascular disease, coronary artery disease, and white race all were associated with fistula failure to mature in their study; however, in this and the previously mentioned studies, it is not clear whether there was any consistent surgical assessment performed perioperatively to guide fistula placement; as such, the results may not be applicable to programs that use pre- or intraoperative surgical assessment to guide fistula placement.Given these uncertainties, we sought to determine the association of various baseline clinical parameters with primary fistula success in a cohort that consisted of all incident dialysis patients between July 1, 1999, and November 1, 2001, in Calgary, Alberta, Canada, the majority of whom had an indirect assessment of vessel diameter intraoperatively to guide the location of fistula placement.  相似文献   
62.
OBJECTIVES: The aim of this study was to investigate the various features of infectious disease (ID) consultations and the usage of antibiotics in a Turkish university hospital. METHODS: A total of 395 consultation requests were recorded during a three-year period. RESULTS: The departments most frequently requesting the consultation services of the ID department were Orthopedics (29.6%), Neurology (18.5%), Cardiology (11.8%) and Internal Medicine (10.4%). The main reasons were for diagnosis of unexplained fever (42.3%) and for antibiotic modification according to culture results (18%). Diagnoses made by the ID consultant were pneumonia (16.7%), urinary tract infections (9.3%), bone and joint prosthesis infections (9.1%) and in 15.7% of the investigated patients, no infectious focus was determined. It was recognized that the use of antibiotics had already been initiated in the great majority of patients (67.1%) before the consultation request. While the current therapy was changed in 57.4% of these patients, antibiotics were not necessary for 9.8%. CONCLUSIONS: Since the most common diagnoses were respiratory and urinary tract or bone and joint prosthesis infections, the ID specialists should have detailed knowledge of these problems. Usage of antibiotics without ID consultation was prevalent, therefore a continuous educational program is a necessity for healthcare workers in the hospital.  相似文献   
63.
BACKGROUND/AIMS: Apoptotic and anti-proliferative effects of heparin on a number of cancers have been described. There have been no studies analyzing the effect of heparin on human hepatoma cells. The aim of this study was to investigate the effect of heparin on human hepatoma cell line, HepG2. METHODOLOGY: HepG2 cell line was cultured with different concentrations of heparin. Colony count, viability assay, percentage of the apoptosis and proliferative index were assessed at the end of the 7th day. Trypan blue was used to assess viability. Apoptosis and proliferative indexes were assessed by flow-cytometry. RESULTS: Hepatoma cells were arrested at the G0/G1 phase with heparin incubation and proliferative indexes decreased significantly in 20, 40 and 80 U/mL of heparin concentrations in comparison with the control (36 +/- 1%, 30 +/- 5% and 29 +/- 8% vs. 44 +/- 1%, p < 0.01). Flow cytometry revealed a statistically significant increase in apoptosis in groups incubated with 40 and 80 U/mL of heparin in comparison with the control (39 +/- 26% and 58 +/- 18% vs. 0.83 +/- 1.3%, p < 0.01). Colony counts per well and viable cells per microL decreased significantly in 80 U/mL of heparin. CONCLUSIONS: Heparin leads to a significant anti-proliferative and an apoptotic effect on human hepatoma cells in vitro.  相似文献   
64.
Tissue injury resulting from ischemia-reperfusion is of fundamental importance. Experimental evidence suggests that the generation of reactive oxygen species is significantly responsible for this type of injury. In the present study, besides investigating the protective role of melatonin on tissue damage caused by intestinal ischemia-reperfusion, the protective activity of this compound was also analyzed in both pre- and post ischemia melatonin-treated rats. The activities of the main antioxidative enzymes, catalase, superoxide dismutase and glutathione peroxidase in the intestine showed significant (P < 0.05) increases in melatonin-treated animals that were subjected to ischemia/reperfusion compared with those subjected only to ischemia/reperfusion. Also, results clearly indicate that the level of malondialdeyhde, an index of lipid peroxidation, decreased significantly (P < 0.05) when rats subjected to intestinal/reperfusion were given melatonin either before ischemia or before reperfusion.  相似文献   
65.
The aim of this study was to measure the alterations in serum trace elements, including zinc and copper in patients with chronic hepatitis C and to compare them with the results of healthy individuals. Seventeen patients with chronic hepatitis C and 17 healthy individuals were included in this study. Serum zinc and cooper concentrations were measured by using atomic absorption spectrophotometer of patients with chronic hepatitis C and the results were statistically compared with those of healthy individuals. Serum zinc concentrations were 105.6+/-22.8 microg/dl in patients with chronic hepatitis C and 94.41+/-19 microg/dl in healthy controls, respectively. Serum copper concentrations were 103.17+/-20.8 microg/dl in patients with chronic hepatitis C and 90.8+/-14.3 microg/dl in healthy subjects, respectively. Serum zinc and copper concentrations were not found statistically different in patients with chronic hepatitis C compared with those of healthy individuals (p>0.05). In conclusion, serum trace element concentrations did not show statistical alterations in patients with chronic hepatitis C compared to healthy subjects.  相似文献   
66.
Iron deficiency anemia (IDA), mostly due to chronic occult bleeding from the gastrointestinal tract, is a common problem in the elderly. This study aimed to determine the prevalence of IDA in the elderly and to investigate the gastrointestinal tract in elderly patients with IDA. 1,388 patients over 65 years were prospectively evaluated for IDA in our outpatient clinic. IDA was defined if decreased hemoglobin concentrations (<13 g/dl for men and <12 g/dl for women) were associated with low serum ferritin levels (<15 ng/ml in men and <9 ng/ml in women). We evaluated the gastrointestinal system of all patients with IDA by upper gastrointestinal endoscopy and colonoscopy regardless of fecal occult blood loss. The prevalence of anemia was found to be 25% (n = 347) in our study population, and 30.5% (n = 106) of these patients with anemia had iron deficiency. Upper gastrointestinal endoscopy and colonoscopy were performed in 96 patients with IDA. Fifty-eight upper gastrointestinal system lesions (55 patients, 57.3%) and 27 colonic lesions (26 patients, 27.1%) were detected. We diagnosed gastrointestinal malignancy in 15 (15.6%) elderly patients with IDA (8 colon, 1 esophageal and 6 gastric cancers). IDA is a common problem in elderly patients; consequently, before iron replacement therapy, patients should be thoroughly investigated regarding a possible association with gastrointestinal malignancy.  相似文献   
67.
BackgroundThe information on electrocardiographic features of patients with coronavirus disease 2019 (COVID-19) is limited. Our aim was to determine if baseline electrocardiographic features of hospitalized COVID-19 patients are associated with markers of myocardial injury and clinical outcomes.MethodsIn this retrospective, single center cohort study, we included 223 hospitalized patients with laboratory-confirmed COVID-19. Clinical, electrocardiographic and laboratory data were collected and analyzed. Primary composite endpoint of mortality, need for invasive mechanical ventilation, or admission to the intensive care unit was assessed.ResultsForty patients (17.9%) reached the primary composite endpoint. Patients with the primary composite endpoint were more likely to have wide QRS complex (>120 ms) and lateral ST-T segment abnormality. The multivariable Cox regression showed increasing odds of the primary composite endpoint associated with acute respiratory distress syndrome (odds ratio 7.76, 95% CI 2.67–22.59; p < 0.001), acute cardiac injury (odds ratio 3.14, 95% CI 1.26–7.99; p = 0.016), high flow oxygen therapy (odds ratio 2.43, 95% CI 1.05–5.62; p = 0.037) and QRS duration longer than >120 ms (odds ratio 3.62, 95% CI 1.39–9.380; p = 0.008) Patients with a wide QRS complex (>120 ms) had significantly higher median level of troponin T and pro-BNP than those without it. Patients with abnormality of lateral ST-T segment had significantly higher median level of troponin T and pro-BNP than patients without.ConclusionsThe presence of QRS duration longer than 120 ms and lateral ST-T segment abnormality were associated with worse clinical outcomes and higher levels of myocardial injury biomarkers.  相似文献   
68.
The herpesviruses infections in equides are caused by five different serotypes of viruses, belonging to family Herpesviridae. The goal of this study was to conduct a seroepidemiological investigation of equine herpesvirus type 1 (EHV-1) and type 4 (EHV-4) in horses and donkeys raised in two provinces and their villages in northeastern Turkey. A total of 666 samples from 423 horses and 243 donkeys that were not immunized against these infections were tested with ELISA. While 52.48% of tested horse sera was found to carry specific antibodies to EHV-1, 83.69% of these serums were found to carry specific antibodies to EHV-4. 51. Eighty-five percent of analyzed donkey samples tested positive for EHV-1 and 64.20% of these samples tested positive for EHV-4 antibodies. When the horse and donkey samples were evaluated together, 52.25% were seropositive for EHV-1 and 76.58% were seropositive for EHV-4. This study showed that EHV-1 and EHV-4 infections are quite common in the horses and donkeys being raised in the areas where the study was carried out. In addition, since the area where the study was carried out in the borders of Armenia and Georgia, the high level of seropositive results for these infections leads to the conclusion that we should consider the risk of diseases spreading to neighboring countries. This is the first study to serologically identify EHV-1 and EHV-4 infections in donkeys raised in Turkey.Key Words: Donkey, Equine herpesvirus type-1, Equine herpesvirus type-4, Horse  相似文献   
69.
Use of pleural fluid C-reactive protein in diagnosis of pleural effusions   总被引:8,自引:0,他引:8  
The aims of the study were to assess whether C-reactive protein (CRP) is a sensitive marker for discriminating between transudative and exudative and pleural effusions to evaluate whether it can be used to distinguish inflammatory pleural effusions from other types of effusion. Pleural fluid and serum CRP levels were obtained in 97 patients with pleural effusion, using an immunoturbidimetric method (Olympus AU-600 autoanalyser). We compared CRP levels between transudates and exudates, inflammatory effusions and other types of effusion. According to the criteria used, 16 patients were included in the transudate group and 81 patients in the exudate group. Pleural fluid CRP levels were significantly lower in the transudate group (P<0.04; 14.9 +/- 4.9 mg l(-1) and 35.5 +/- 4.9 mg l(-1) respectively). Also, the ratio of pleural fluid to serum was significantly lower in the transudate group (P<0.009; 0.8 +/- 0.5 mg l(-1) and 2.8 +/- 0.7 mg l(-1), respectively). In the exudate group, 35 patients had neoplastic effusions, 10 chronic non-specific pleurisy, 19 tuberculous pleurisy, 16 parapneumonic effusion and one Dressler Syndrome. When these sub-groups were compared, the parapneumonic effusion subgroup CRP levels (mean 89 +/- 16.3 mg l(-1)) were significantly higher than those in the other subgroups, other exudate of neoplastic effusion, tuberculous pleurisy and chronic non-specific effusion and the transudate group (P<0.0001; P<0.0001; P<0.0004 and P<0.0001, respectively). The ratio between pleural fluid and serum CRP was significantly higher in the parapneumonic effusion subgroup than in the neoplastic subgroup (P<0.0002; 6.6 +/- 2.7 mg l(-1) and 1 +/- 0.2 mg l(-1), respectively). Pleural fluid CRP levels > 30 mg l(-1) had a high sensitivity (93.7%) and specificity (76.5%) and a positive predictive value of 98.4%. In the differential diagnosis of pleural effusions, higher CRP levels may prove to be a rapid, practical and accurate method of differentiating parapneumonic effusions from other exudate types. Although the high level of CRP obtained in the exudate group may be due to the number of patients with parapneumonic effusion who were included, the pleural CRP level may also be helpful in discriminating between exudative and transudative pleural effusions.  相似文献   
70.
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