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Background:Ischemia-reperfusion injury is a histopathological event and is an important cause of morbidity and mortality after hepatobiliary surgery. We aimed to investigate the protective effect of uridine on hepatic ischemia-reperfusion injury in rats.Methods:he animals were divided into 4 groups (n = 8): group I (control), group II: ischemia-reperfusion (30 minutes ischemia and 120 minutes reperfusion), group III: ischemia-reperfusion + uridine (at the beginning of reperfusion), and group IV: ischemia-reperfusion + uridine (5 minutes before ischemia-reperfusion). Uridine was administered a single dose of 30 mg/kg IV. The 3 elements of the hepatoduodenal ligament (hepatic artery, portal vein, and biliary tract) were obliterated for 30 minutes. Then hepatic reperfusion was achieved for 120 minutes.Results:In the ischemia-reperfusion group, both liver tissues and serum chymase activity and high-temperature requirement A2 levels were higher. Severe central vein dilatation and congestion, widening sinusoidal range, diffuse necrotic hepatocytes and dense erythrocyte accumulation in sinusoids, and strongly inducible nitric oxide synthase expression were seen in the ischemia-reperfusion group. A clear improvement was seen in both uridine co-administration and pretreatment groups.Conclusion:Our results revealed that uridine limits the development of liver damage under conditions of ischemia-reperfusion, thus contributing to an increase in hepatocyte viability.  相似文献   
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AIM: To evalaute the effect of fixed-combination latanoprost 0.005%/timolol maleate 0.5% and dorzolamide hydrochloride 2%/timolol maleate 0.5% on postoperative intraocular pressure after phacoemulsification cataract surgery. METHODS: This study is a prospective, randomized, double-masked and placebo-controlled. The study included 90 eyes of 90 patients which were scheduled to have phacoemulsification surgery. Patients were randomly assigned preoperatively to 1 of 3 groups (30 eyes of 30 patients). Two hour before surgery, the patients received one drop latanoprost/timolol (group 1), dorzolamide/timolol (group 2) and placebo (group 3, control group). The IOPs were measured at preoperative and postoperative 4, 8, and 24 hours. RESULTS: The preoperative mean intraocular pressure was not statistically significant between both drug groups and control group. In group 1 and 2, the postoperative mean IOP [group1: (14.03±3.15)mmHg and group 2: (14.16±4.43)mmHg] at 24 hours were significantly lower than the control group [(16.93±3.70)mmHg, (P<0.05)]. In addition, the postoperative mean IOP of group 1 [(14.90±3.69)mmHg] at 8 hours was significantly lower than the control group [(17.70±3.89)mmHg, (P<0.05)], but there was no significant difference between group 2 [(16.16±5.23)mmHg] and control group at 8 hours (P>0.05). CONCLUSION: When compared with placebo, the use of preoperative fixed combination of latanoprost/ timolol and dorzolamide/timolol is an effective method for preventing intraocular pressure elevation in 24 hours after phacoemulsification surgery, but did not completely prevent IOP spikes.  相似文献   
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Objective: Autoimmune chronic thyroiditis (ACT) is characterized by lymphocyte infiltration in the thyroid gland and the presence of antithyroid antibodies in serum. Medical treatment does not affect antibody levels and treatment decision is not definite yet for the euthyroid patients. We aimed to evaluate cardiac autonomic function and global left ventricular performance in autoimmune euthyroid chronic thyroiditis and determine the need for medical treatment. Method: We studied 30 ACT patients and 25 healthy control subjects. Cardiac autonomic function is evaluated by heart rate recovery (HRR). Global left ventricular performance is evaluated by two‐dimensional echocardiography and pulsed‐wave tissue Doppler echocardiography. Results: There was no difference between patients and controls with respect to clinical and biochemical parameters except hemoglobin (13.67 ± 1.25 g/dL, 14.51 ± 1.35 g/dL, p:0.047) and low density lipoprotein (120.71 ± 24.91 mg/dL, 100.55 ± 14.73 mg/dL, p: 0.003). Tei index was significantly higher in ACT group (0.521 ± 0.074, 0.434 ± 0.034, P < 0.0001). E′/A′ was found to be significantly lower (1.234 ± 0.42, 1.750 ± 0.291, P < 0.0001) and E/E′ was found to be higher than the controls (8.482 ± 0.449, 6.039 ± 0.209, P < 0.0001). HRR was significantly lower than the controls (20 ± 4 BPM, 30 ± 8 BPM, P < 0.0001). Conclusion: Although left ventricular performance is found to be normal by conventional echocardiographic methods, it is found to be impaired when Tei index and tissue Doppler parameters are used. Cardiac autonomic function is also impaired in ACT patients. As a result of these cardiac changes, medical treatment may be considered earlier, even at the euthyroid stage. (Echocardiography 2011;28:15‐21)  相似文献   
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In this work, the flexure properties of nanostitched and nanoprepreg three dimensional (3D) para-aramid/phenolic composites were studied. Four types of composite were developed. They were called stitched/nano, stitched, base/nano and base. The flexure strength and modulus of the stitched/nano composites were slightly improved compared to those of the base composites due to the addition of the stitching yarn and multiwall carbon nanotubes (MWCNTs). The flexure failure of the base and base/nano structures was matrix peeling and large delaminated areas, whereas the stitched and stitched/nano composites had warp deformation and no visible matrix/fiber damage. In addition, the delaminated areas were severely restricted. The results showed that introducing the stitching fiber and multiwall carbon nanotubes in the base structure improved its out-of-plane failure properties as a form of restricted delamination and they acted as delamination barriers around the regions. Therefore, stitched/nano p-aramid/phenolic composites could be considered as damage tolerant materials.

The bending properties of four types of nanostitched and nanoprepreg three dimensional (3D) para-aramid/phenolic composite were studied. Stitched or stitched/nano p-aramid/phenolic composites could be considered as damage tolerant materials.  相似文献   
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OBJECTIVE: Recent studies have suggested an association between a deletion variant of the angiotensin-converting enzyme (ACE) gene and diabetic nephropathy. However, this finding has not been confirmed by all investigators. Furthermore, an M235T variant of the angiotensinogen (AGT) gene has been associated with hypertension, an important risk factor for the development and progression of diabetic nephropathy. RESEARCH DESIGN AND METHODS: We investigated the relationship of the ACE insertion/deletion (I/D) and AGT M235T gene polymorphisms in Turkish patients with type 2 diabetes mellitus (DM) with and without diabetic nephropathy. A total of 102 individuals were screened for the presence of the ACE I/D and AGT M235T polymorphism: 46 individuals who had type 2 DM with diabetic nephropathy and, as controls, 56 individuals who had type 2 DM without diabetic nephropathy. Gene polymorphisms were determined by the specific melting temperature (T(m)) values of the resulting amplicons after real-time online polymerase chain reaction and melting curve analysis. RESULTS: The frequencies of the ACE DD, ID, and II genotypes were 34.8%, 37.0%, and 28.3%, respectively, among type 2 diabetic patients with nephropathy, and 33.9%, 42.9%, 23.2%, respectively (P=.788), in the control subjects without diabetic nephropathy. On the other hand, the frequencies of the AGT MM, MT, and TT genotypes among the same groups were 26.1%, 52.2%, 21.7% and 26.8%, 57.1%, 16.1%, respectively (P=.758). CONCLUSIONS: There were no differences in the frequencies of the AGT M235T and ACE I/D genotypes between Turkish patients with type 2 DM with and without nephropathy.  相似文献   
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Erdogan S  Ergin M  Tuncer I 《Neoplasma》2003,50(5):326-330
The c-erbB-2 gene codes for a membrane receptor protein that is homologous to the epidermal growth factor receptor. Differential polymerase chain reaction (PCR) is an alternative semi-quantitative method for evaluating gene amplification and can be performed in formalin-fixed paraffin-embedded specimens. We aimed to compare differential PCR and IHC (immunohistochemistry) in the determination of c-erbB-2 status of breast cancers. Correlation between the prognostic impact of c-erbB-2 gene amplification and protein overexpression with conventional prognostic factors were also evaluated. Differential PCR and IHC for c-erbB-2 were performed on formalin-fixed paraffin sections of 60 invasive breast cancers. Results and the relation with the other prognostic parameters were compared. A highly significant degree of concordance between differential PCR and IHC in the evaluation of c-erbB-2 status of breast carcinoma was detected. Amplification and overexpression were significantly related to the number of metastatic lymph nodes, histologic grade, and lymphatic invasion but not age, histologic type, tumor size and estrogen status. We demonstrated and confirmed the importance of c-erbB-2 overexpression and amplification as a single and combined prognostic parameter together with conventional factors and confirmed that it can be detected by both immunohistochemistry and differential PCR techniques in breast carcinoma. This semi-quantitative technique provides reliable results and can be used routinely.  相似文献   
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