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11.
OBJECTIVE: The purpose of this study was to compare the left atrial appendage (LAA) tissue Doppler imaging (TDI) with the classical LAA function parameters in patients with mitral valve disease. METHODS: Twenty patients who had pure mitral regurgitation (group 1), 20 patients who had pure rheumatic mitral stenosis (group 2), and 20 healthy patients (group 3) were included in this study. All the cases were sinus rhythm. In order to determine the LAA functions, LAA late filling (LAALF), and late emptying (LAALE) flow velocities and LAA fractional area change (LAAFAC) were measured. LAA tissue Doppler evaluations were obtained from the PW Doppler, which was placed on the LAA lateral wall in a transverse basal short-axis approach. LAA late systolic (LAALSW) and late diastolic (LAALDW) wave velocities were obtained from TDI records transesophageal echocardiography (TEE). RESULTS: There were no significant differences among groups 1, 2, and 3 in terms of age, left ventricular (LV) ejection fraction, gender, and heart rate. No differences were observed between group 1 and the control group with respect to LAALE, LAALF, and LAAFAC. LAALE velocity and LAAFAC were significantly decreased in group 2 than group 1. LV diastolic diameter was significantly greater, whereas LAALSW and LAALDW velocities were significantly decreased in group 1 compared with group 3. There were no differences between groups 1 and 2 regarding to LAALSW and LAALDW velocities. LAALE, LAALF, LAALSW, LAALDW velocities, and LAAFAC were significantly decreased in group 2 than group 3. CONCLUSION: The TDI method may detect the LAA systolic dysfunctions, which cannot be detected using classical methods, on tissue level in patients with mitral regurgitation. In addition, the deterioration of the LAA functions at tissue level in patients with rheumatic mitral stenosis was also detected.  相似文献   
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13.
This experimental study was performed to investigate the role of ischemia–reperfusion injury on retinal nitric oxide activity and to determine whether octreotide, the synthetic analogue of natural somatostatin, modifies the nitric oxide activity during retinal ischemia–reperfusion in a quinea pig model. Three groups of seven pigmented male quinea pigs were formed; Control, Ischemia and the Ischemia/Octreotide groups. 90 minutes of pressure-induced retinal ischemia and 24 h of reperfusion were established in the ischemia and ischemia/octreotide groups. Saline for the ischemia group and 50 g/kg of octreotide for the ischemia/octreotide group were administered intraperitoneally five times with 6-h intervals. At the end of the reperfusion period both eyes of the animals of the three groups were enucleated. One eye of each animal was randomly selected for biochemical assay and the other for histopathological analysis. Retinal nitrate levels were measured and histopathological changes were evaluated in the groups. The mean retinal nitrate levels of the control, ischemia and ischemia/octreotide groups were 157.6±25.2, 106.4±20.1 and 96.4±17.7 mol/l, respectively. Nitrate levels decreased significantly both in the ischemia (p<0.01) and ischemia/octreotide (p<0.01) groups versus control. In the ischemia group, retinal histopathological changes, which were different from the control group, were prominent edema, polymorphonucleated leukocytes infiltration and vacuolated spaces in the inner retina. No significant change was observed in the histopathological specimens of the ischemia/octreotide group. Significant increase in the thickness of the inner plexiform layer of the retina of the ischemia group was observed versus the control and ischemia/octreotide groups (p<0.01 and p<0.01, respectively).The thickness of the inner plexiform layer of the retina of the ischemia/octreotide group did not change versus the control group. It was concluded that nitric oxide activity decreased during retinal ischemia–reperfusion and, although octreotide prevented the histopathological damage, it could not ameliorate the nitric oxide activity of the retina.This study was presented in part at the 23rd Congress of the European Society of Ophthalmology.  相似文献   
14.
BACKGROUND: Peritoneal adhesions are pathological fibrotic bands developing after mesothelial damage. Transforming growth factor beta-1 (TGF-beta1) has mitogenic activities for macrophages and fibroblasts. Over-expression of TGF-beta1 has been implicated in the pathogenesis of several fibrotic disorders. Angiotensin II increases the expression of the TGF-beta1 in fibroblasts. The aim of the study was to investigate the effect of angiotensin converting enzyme inhibitor (ACE) on intraperitoneal adhesions. MATERIALS AND METHODS: Thirty male Wistar albino rats were divided into two groups. In the first procedure, laparotomy was performed through a 3-cm midline incision. Ileum was divided above 10 cm from ileocecal valve and a single-layer ileoileal anastomosis was performed. Although no treatment was given to rats in group 1, lisinopril (an ACE inhibitor) was given to rats in group 2 for postoperative 7 days in drinking water. Estimated amount of supplied lisinopril was 6.5 mg/kg/day. On postoperative 8th day, relaparotomy was performed and adhesions were evaluated. At the same time, blood samples were taken for TGF-beta1 measurements. RESULTS: Adhesion severity was significantly less in the ACE inhibitor group (P < 0.001). While mean TGF-beta1 level was 860.3 +/- 108.1 pg/dl (mean +/- SD) in control group, it was 335.8 +/- 52.4 pg/dl in ACE inhibitor group (P < 0.001). There was a significant correlation between serum TGF-beta1 levels and grade of adhesions (r = 0.948). CONCLUSION: It was concluded that ACE inhibitors might be useful for preventing peritoneal adhesions.  相似文献   
15.
The objective of this prospective study was to determine the levels of manganese (Mn), copper (Cu), and zinc (Zn) levels in both nail and serum from patients with epilepsy. For this purpose, levels of these elements were measured in 31 patients with epilepsy and 19 healthy subjects. Element analyses were carried out by atomic absorption spectrophotometer (AAS). Increased Mn levels were detected in nail of patients with epilepsy compared to healthy controls (P<.008). The main nail Zn and Cu levels were found to be unchanged in epileptic patients compared to control subjects. There were no significant differences in serum Mn and Zn levels between epileptic patients and control subjects. However, there was a statistically significant increase in serum Cu levels in patients with epilepsy in comparison with control group (P<.009). Our results demonstrate that some trace element levels may vary in epileptic patients, and because of the more stable status, the analysis of these element levels in some tissues such as nail might be superior to serum analysis.  相似文献   
16.
A child with epidermolysis bullosa and aplasia cutis congenita is presented. This is a very rare condition that represents an unusual manifestation of epidermolysis bullosa. Management of aplasia cutis congenita is controversial and may be conservative, surgical, or a combination of the two. In this patient, surgical treatment with split-thickness skin grafts failed, and conservative treatment using silver-sulfadiazine cream dressings was instituted.  相似文献   
17.
The apoptotic bodies were observed aging in osteoarthritic cartilage and meniscus but there is still a lack of knowledge in the literature about the relationship between meniscal injury and apoptosis. The aim of this study is to investigate the apoptotic changes on meniscal tears caused by degeneration and trauma. Thirty-eight specimens of human meniscal tissues harvested from cadavers and patients were selected from groups below the age of 40. There were 14 normal meniscal tissues from cadavers in the control group. There were 24 meniscal tissues harvested from patients who had had arthroscopic operations for meniscal tear due to degeneration or trauma. The torn meniscal samples were divided into two groups according to their etiologies, either degenerative or traumatic. Apoptotic cells were investigated in each of the three groups in the histopathological examination. There was statistically significant difference among the groups according to apoptotic index (p < 0.01). The mean indexes of apoptosis in both groups of torn meniscus (group 2 = 0.497 and group 3 = 0.725) were significantly higher than that in the normal tissue (group 1 = 0.237) (p < 0.01) but the difference between groups 2 and 3 was not significant (p > 0.001). This study indicates that an increase in the amount of apoptosis appeared to have a close relationship with meniscal tear caused by either trauma or degenerative changes.  相似文献   
18.
Bone tunnel enlargement associated with anterior cruciate ligament (ACL) reconstruction has recently become a topic of interest in the literature. This association was examined, along with the effect of femoral and tibial tunnel enlargement on the clinical results of ACL reconstruction performed with either bone-patellar tendon-bone (BPTB) or hamstring (HST) autografts. Forty-six patients underwent arthroscopic ACL reconstruction (23 receiving BPTB autograft and 23 HST) between March 1999 and July 2001. Thirty patients (13 receiving BPTB autograft and 17 HST) completed the last clinical and radiologic evaluations and were included in the study. The mean age of patients in the HST group was 29.8 years (range 18–39) and that in the BPTB group was 27.6 years (range 20–37). The mean follow-up period was 24.6 months (range 12–36) in HST group and 18.5 months (range 12–40) in BPTB group. The effect of tunnel enlargement on the clinical results was evaluated by comparing preoperative and postoperative Lysholm, Tegner, and International Knee Documentation Committee scores and ligament laxity measurements between and within the groups. Postoperative femoral and tibial tunnel diameters in both groups were significantly larger than their corresponding preoperative tunnel diameters. In an intergroup evaluation, the enlargement of the tibial tunnel was similar in both groups (P=.556), but the femoral tunnel diameter was significantly larger in the HST group than in the BPTB group (P>.001). Preoperative laxity of the knees significantly improved after the operations in both groups, but no difference between the groups was evident at the final follow-up visit. No correlation between tunnel widening and the clinical results of the BPTB and HST procedures was observed.  相似文献   
19.
Vascular endothelial growth factor and oxidative damage in cancer   总被引:1,自引:0,他引:1  
OBJECTIVES: VEGF may be an indicator for the angiogenic potential of a tumor and stimulates NO which plays complex roles in cancer. In our study, we investigated the levels of MDA, NO and VEGF in the plasma of various types cancer patients (untreated, yet). DESIGN AND METHODS: The level of VEGF was determined by using ELISA. Plasma MDA, NO and VEGF levels were measured in 45 patients with various cancer types and in 21 healthy subjects. RESULTS: Plasma MDA and VEGF levels were significantly higher than those of the healthy subjects (p < 0,0001). NO levels of the patients were significantly lower vs. the healthy subjects (p < 0,001). CONCLUSIONS: Increased plasma VEGF and MDA concentrations and decreased plasma NO levels have been found in patients with various types of human cancer. Howewer, the prognostic and clinical significance of plasma VEGF in cancer patients is unknown.  相似文献   
20.

Background

Macintosh laryngoscopes are widely used for endotracheal intubation training of medical students and paramedics whereas there are studies in the literature that supports videolaryngoscopes are superior in endotracheal intubation training. Our aim is to compare the endotracheal intubation time and success rates of videolaryngoscopes and Macintosh laryngoscopes during endotracheal intubation training and to determine the endotracheal intubation performance of the students when they have to use an endotracheal intubation device other than they have used during their education.

Methods

Endotracheal intubation was performed on a human manikin owing a standard respiratory tract by Macintosh laryngoscopes and C-MAC® videolaryngoscope (Karl Storz, Tuttligen, Germany). Eighty paramedic students were randomly allocated to four groups. At the first week of the study 10 endotracheal intubation trials were performed where, Group‐MM and Group‐MV used Macintosh laryngoscopes; Group‐VV and Group‐VM used videolaryngoscopes. Four weeks later all groups performed another 10 endotracheal intubation trial where Macintosh laryngoscopes was used in Group‐MM and Group‐VM and videolaryngoscopes used in Group‐VV and Group‐MV.

Results

Success rates increased in the last 10 endotracheal intubation attempt in groups MM, VV and MV (p = 0.011; p = 0.021, p = 0.290 respectively) whereas a decrease was observed in group‐VM (p = 0.008).

Conclusions

The success rate of endotracheal intubation decreases in paramedic students who used VL during endotracheal intubation education and had to use Macintosh laryngoscopes later. Therefore we believe that solely videolaryngoscopes is not enough in endotracheal intubation training programs.  相似文献   
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