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排序方式: 共有5363条查询结果,搜索用时 15 毫秒
31.
Tsai MY Aras O Sozen H Hanson NQ Woll PS Arends VL Hunninghake DB Matas AJ 《The Journal of laboratory and clinical medicine》2004,143(6):340-343
An increased prevalence of hyperhomocysteinemia has been observed among patients with end-stage renal disease, and numerous studies have demonstrated that kidney function is one of the most important determinants of plasma total homocysteine (tHcy) concentration. In an effort to understand the mechanism of hyperhomocysteinemia in renal disease, we chose, as our model, living kidney donors who had undergone uninephrectomy. We studied 10 living kidney donors and measured fasting plasma tHcy, plasma creatinine, folate, vitamins B(12) and B(6), and high-sensitivity C-reactive protein (hsCRP) 24 hours before nephrectomy and 2 days, 6 weeks, and 6 months after nephrectomy compared to the values 24 hours before nephrectomy. Mean fasting tHcy and creatinine concentrations were significantly higher in donors 2 days, 6 weeks and 6 months after nephrectomy they were 24 hours before nephrectomy. Both the increases in tHcy levels 2 days after nephrectomy and subsequent decreases 6 weeks and 6 months after are paralleled by the changes in plasma creatinine values, although neither returned to its presurgery value. Decreases in tHcy are significantly correlated with decreases in creatinine values. The B vitamins were unchanged, and the hsCRP level was increased 2 days after surgery but had returned to the baseline level after 6 weeks. We conclude that tHcy and creatinine levels parallel each other after uninephrectomy and that the gradual decrease in tHcy is accounted for by hypertrophy of the remaining kidney. Our results, the first to be obtained from living kidney donors, support the hypothesis that renal metabolism of tHcy is the mechanism responsible for the correlation between renal function and plasma tHcy level. 相似文献
32.
Altin T Akyurek O Vurgun K Beton O Sayin T Kilickap M Karaoguz R Guldal M Erol C 《Pacing and clinical electrophysiology : PACE》2007,30(11):1356-1362
BACKGROUND: Pacemaker and implantable cardioverter defibrillator (ICD) implantation increases cardiac troponin I (cTnI) levels which indicates myocardial injury. During implantation of a cardiac resynchronization therapy (CRT) device, balloon inflation for coronary sinus (CS) venogram, cannulation of CS side branch, and electrode advancement may interfere with CS drainage and, hence, may decrease the washout of toxic metabolites from the heart. Thus, CRT implantation may further increase cTnI levels. In this study, we investigated the effects of CRT implantation on cTnI release. METHODS: We included 10 patients (mean age = 57 +/- 15 years) in whom a successful transvenous CRT system was implanted (CRT group). Twenty patients (mean age = 65 +/- 10 years) who underwent a transvenous pacemaker or ICD implantation were included as the control group. Blood samples for cTnI were drawn at baseline and at six, 12, 18, and 24 hours thereafter. RESULTS: Baseline median cTnI levels were similar in CRT and control groups (0.03 ng/mL vs 0.02 ng/mL, respectively; P = 0.1). Postoperative cTnI levels during 24 hours were significantly higher in the CRT group (P < 0.05) by two-way repeated measures of analysis of variance. Post hoc analysis revealed that cTnI levels were higher at the 6th, 12th, 18th, and 24th hours compared to baseline levels (P < 0.001, P < 0.001, P < 0.01, and P < 0.01, respectively). There was a significant difference in the area under the curves (AUCs) of cTnI measurements (1.79 hr.ng/mL in the CRT group and 0.78 hr.ng/mL in the control group, P < 0.05). CONCLUSION: Postoperative cTnI levels were higher after CRT implantation than simple pacemaker/ICD implantation. This may be due to CS manipulation during CRT implantation. 相似文献
33.
Yasemin Gulcan Kurt Bulent Kurt Omer Ozcan Turgut Topal Abdullah Kilic Tuba Muftuoglu Cengizhan Acikel Kenan Sener Fatih Sahiner Nuri Yigit Ibrahim Aydin Semih Alay Safak Ekinci 《Annals of Indian Academy of Neurology》2015,18(2):187-193
Context:
Muscle biopsy samples must be frozen with liquid nitrogen immediately after excision and maintained at -80°C until analysis. Because of this requirement for tissue processing, patients with neuromuscular diseases often have to travel to centers with on-site muscle pathology laboratories for muscle biopsy sample excision to ensure that samples are properly preserved.Aim:
Here, we developed a preservative solution and examined its protectiveness on striated muscle tissues for a minimum of the length of time that would be required to reach a specific muscle pathology laboratory.Materials and Methods:
A preservative solution called Kurt-Ozcan (KO) solution was prepared. Eight healthy Sprague-Dawley rats were sacrificed; striated muscle tissue samples were collected and divided into six different groups. Muscle tissue samples were separated into groups for morphological, enzyme histochemical, molecular, and biochemical analysis.Statistical method used:
Chi-square and Kruskal Wallis tests.Results:
Samples kept in the KO and University of Wisconsin (UW) solutions exhibited very good morphological scores at 3, 6, and 18 hours, but artificial changes were observed at 24 hours. Similar findings were observed for the evaluated enzyme activities. There were no differences between the control group and the samples kept in the KO or UW solution at 3, 6, and 18 hours for morphological, enzyme histochemical, and biochemical features. The messenger ribonucleic acid (mRNA) of β-actin gene was protected up to 6 hours in the KO and UW solutions.Conclusion:
The KO solution protects the morphological, enzyme histochemical, and biochemical features of striated muscle tissue of healthy rats for 18 hours and preserves the mRNA for 6 hours. 相似文献34.
35.
Antibiotic resistance of faecal enterococci in poultry, poultry farmers and poultry slaughterers 总被引:6,自引:0,他引:6
van den Bogaard AE Willems R London N Top J Stobberingh EE 《The Journal of antimicrobial chemotherapy》2002,49(3):497-505
The prevalence of resistance in enterococci to antibiotics, commonly used for therapy in poultry or as antimicrobial growth promoters (AMGPs), was determined in faecal samples of two chicken populations: broilers in which antibiotic and AMGP use is common and laying-hens with a low antibiotic usage. In addition faecal samples were examined from three human populations: broiler farmers, laying-hen farmers and poultry slaughterers. MICs of an extended panel of antibiotics for a randomly chosen gentamicin- or vancomycin-resistant enterococcal isolate from each faecal specimen were also determined. The prevalence of resistance for all antibiotics tested was higher in broilers than in laying-hens. Resistance in faecal enterococci of broiler farmers was for nearly all antibiotics higher than those observed in laying-hen farmers and poultry slaughterers. The overall resistance in broilers was correlated with the resistance in broiler farmers and in poultry slaughterers. No correlation between the results obtained in the laying-hens with any of the other populations was found. The 27 gentamicin-resistant isolates all showed high-level resistance to gentamicin and two of these isolates, both Enterococcus faecium, were resistant to all antibiotics tested, except vancomycin. The 73 vancomycin-resistant enterococci (VRE) isolated from the five populations belonged to four different species and in all isolates the vanA gene cluster was detected by blot hybridization. The pulsed-field gel electrophoresis (PFGE) patterns of these vancomycin-resistant enterococci were quite heterogeneous, but Enterococcus hirae isolates with the same or a closely related PFGE pattern were isolated at two farms from the broiler farmer and from broilers. Molecular characterization of vanA-containing transposons of these isolates showed that similar transposon types, predominantly found in poultry, were present. Moreover, similar vanA elements were not only found in isolates with the same PFGE pattern but also in other VRE isolated from both humans and chickens. The results of this study suggest transmission of resistance in enterococci from animals to man. For VRE this might be clonal transmission of animal strains, but transposon transfer seems to occur more commonly. 相似文献
36.
Ergun Tozkoparan Omer Deniz Ergun Ucar Hayati Bilgic Kudret Ekiz 《Clinical chemistry and laboratory medicine》2007,45(8):1009-1013
BACKGROUND: Recent studies show that platelets have important roles in the immune system. Little is known about the clinical significance of platelet indices. Changes in platelet indices, including platelet distribution width (PDW), mean platelet volume (MPV) and plateletcrit, in pulmonary tuberculosis were investigated. METHODS: Platelet indices were quantified in 82 patients with active tuberculosis and 87 patients with inactive or non-tuberculous disease (controls). Radiological extent of the disease was assessed. RESULTS: There were significantly higher PDW (40.9+/-23.5% vs. 27.0+/-14.5%), MPV (10.05+/-2.36 vs. 8.83+/-1.47 fL) and plateletcrit (0.330+/-0166% vs. 0.266+/-0.128%) values in the active tuberculosis group, which decreased significantly with anti-tuberculous therapy. Erythrocyte sedimentation rate and plateletcrit showed significant correlation (r=0.54 and r=0.66) with radiological extent of tuberculosis, while PDW and MPV correlations with radiological extent of tuberculosis were also significant but weaker (r=0.31 and r=0.23). In a subpopulation of controls with pneumonia, which leads to acute phase reaction, PDW, MPV and plateletcrit values were significantly lower than in the tuberculosis group. CONCLUSIONS: We suggest that PDW, MPV and plateletcrit change in tuberculosis and that these changes may not reflect only acute phase reaction and disease activity. The potential role of platelet indices in tuberculosis immunopathogenesis remains to be investigated. 相似文献
37.
Mustafa Adem Tatlisu Adem Atici Fatma Betul Ozcan Mehmet elik Eray Kirac Omer Faruk Baycan Mustafa Caliskan 《Arquivos brasileiros de cardiologia》2022,119(3):436
BackgroundThe soluble tumor necrosis factor-like weak inducer of apoptosis (sTWEAK) is a member of the TNF superfamily that plays a critical role in proliferation and inflammation in the arterial circulation.ObjectivesThis prospective study aimed to show the relationship between the sTWEAK levels and coronary artery calcification (CAC) in patients with chronic kidney disease (CKD).MethodsThis prospective study included 139 consecutive patients undergoing computed coronary angiography for any reason except for acute coronary syndromes from August 2020 to February 2021. A total of 12 patients were excluded from the study due to exclusion criteria. Patients were divided into two groups with regard to having a CAC score of less than 400 (n=84) and 400 or more (n=43). Significance was assumed at a 2-sided p<0.05.ResultsAs the CAC score increased, sTWEAK levels presented a statistically significant decrease, and a strong relationship between sTWEAK levels and the CAC score (r: -0.779, p<0.001) was observed. The ROC analysis revealed that the optimal cut-off level of sTWEAK for predicting the CAC score of 400 was 761 pg/mL with a sensitivity of 71% and a specificity of 73% (AUC: 0.78; 95% CI:0.70-0.85; p < 0.001)ConclusionsEven though the large-scale studies showed a positive correlation between eGFR and the sTWEAK levels, some studies found the increased sTWEAK levels to be associated with mortality and the severity of the coronary artery system in patients with CKD. Our results support our hypothesis that the sTWEAK level shows coronary calcification rather than other types of atherosclerotic plaques. 相似文献
38.
ObjectiveKörner's septum is a dense bony lamina dividing the mastoid cavity into superficial squamous and deeper petrosal portions at the level of antrum. In this study, we aimed at investigating the association of the Körner's septum with the length of the Cog process and the volume of anterior epitympanic recess (AER), using the 3-dimensional reconstruction models based on high resolution computed tomography sections of the temporal bone.MethodsUsing OsiriX software for MacOS (version 3.8.1, Pixmeo), we measured the volumes from three- dimensional models of anterior epitympanic recess. Anterior epitympanic recess volumes and Cog process lengths of the temporal bones with and without Körner's septum were compared.ResultsCog process length was significantly higher, and AER volume was significantly lower in patients with Körner's septum compared to the patients without. (p < 0.001). Additionally, Cog process length was significantly (p = 0.008), negatively, but weakly (rho= ?0.24) correlated with AER volume.ConclusionTemporal bones with Körner's septum had a longer Cog process and a smaller AER. 相似文献
39.
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