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111.
112.
The liver is the primary site of synthesis for the majority of coagulation factors. There are published accounts of liver donor-to-recipient transmission of protein C deficiency with dysfibrinogenemia and factor XI deficiency. In this article, we report what we believe to be the first observation, of transmission of factor VII deficiency, a rare, autosomal recessive coagulation disorder, from an affected liver donor to a naive liver recipient. At 300 days after transplantation, the recipient remains with an isolated prolongation of the prothrombin time and a below-normal level of factor VII, and has had no bleeding complications. Received: 6 November 1998 Received after revision: 26 April 1999 Accepted: 4 May 1999  相似文献   
113.
The complications of right atrial catheters (RACs) in pediatric oncology patients are unknown for centers in developing countries. This study examined the complications of RACs at Ankara University Medical School, Turkey. A total of 90 RACs were placed in 61 children for long-term chemotherapy with a total experience of 15,536 catheter days. The rate of catheter-related sepsis was 4.9 episodes per 1000 catheter days. Coagulase-negative staphylococci and Candida species were the most common organisms, accounting for 25.0 and 13.1% of all organisms, respectively. The most common reasons for the removal of the RACs were infection (42.4%) and dislodgement (32.2%). The rates of complications were significantly higher in this study than in western studies. This increase could be explained by the differences in catheter care practices in the Turkish center. In conclusion, the use of RACs in a developing country necessitates an appraisal of the benefits and risks for each patient and improvement of catheter care procedures.  相似文献   
114.
OBJECTIVES: The oxygen toxicity risk of hyperbaric oxygen (HBO) treatment has long been of interest. However, there are no comprehensive articles describing the relationship between HBO protocols and oxidative parameters used clinically. The purpose of this study was to determine the effects of various HBO pressure modalities on the oxidative values of rat lung, brain, and erythrocytes. DESIGN AND METHODS: A total of 64 male Sprague-Dawley rats was randomly divided into 7 groups. Group A was used as a control. Groups C to G were subjected to 100% oxygen at a pressure of 1, 1.5, 2, 2.5, and 3 ATA (atmosphere absolute), respectively, for 2 h. Group B was exposed to normal atmospheric air at 3 ATA for the same duration. The rat's lung, brain, and blood were taken immediately after the exposure and thiobarbituric acid reactive substances (TBARS) and superoxide dismutase (SOD) levels were determined. RESULTS: Both TBARS levels and SOD activity increased concordantly with the pressure increase. Although a statistically significant change in TBARS levels started from 100% oxygen exposure at 1 ATA (normobaric), SOD activity was affected after 2 ATA. A significant correlation exists between exposure pressure and the aforementioned parameters. Ambient air exposure at 3 ATA did not affect any parameters besides the brain TBARS levels. CONCLUSIONS: It is clear that HBO exposure causes oxidative stress. The main reason for this effect seems to be exposure to pure oxygen, since pure high pressure has no significant effect on the aforementioned parameters. However, clinicians should use as low pressures as possible since all oxidative parameters appear to be directly proportional to the extent of HBO exposure.  相似文献   
115.

Background

Assessment of left ventricular (LV) thrombosis risk after acute myocardial infarction (AMI) is important because of potential embolic sequelae that are reduced by oral anticoagulant agents. The goal of this study was to investigate whether early assessment of LV systolic and diastolic performance with pulsed wave tissue Doppler ultrasound scanning (PWTD) predicts LV thrombosis after AMI.

Methods

Two-dimensional and Doppler ultrasound scanning echocardiographic examinations were performed in 92 consecutive patients (age, 58 ± 10 years; 11 women) with first anterior AMI within 24 hours after arrival to the coronary care unit. From the apical 4-chamber view, the mitral annular velocities were recorded at the lateral corner of the mitral annulus with PWTD. The myocardial performance index (MPI), which combines parameters of both systolic and diastolic ventricular function, was calculated from the PWTD recordings. To analyze LV thrombus formation, the 2-dimensional echocardiographic examination was repeated on days 3, 7, 15, and 30. The patients were divided in 2 groups according to LV thrombus formation.

Results

LV thrombus was found in 32 of 92 patients (35%; group 1) and was not found in 60 patients (65%; group 2). The MPI was significantly higher in group 1 than in group 2 (0.73 ± 0.20 vs 0.53 ± 0.14; P <.001). When an MPI >0.6 was used as the cutoff, LV thrombus formation could be predicted with a sensitivity rate of 81%, a specificity rate of 73%, a positive predictive value of 62%, and a negative predictive value of 88%. In multivariate analyses, only MPI and LV wall motion score index were independent predictors of LV thrombus formation (P = .038 and P = .047, respectively).

Conclusions

The MPI derived with PWTD soon after admission appears to be a useful parameter for assessing the risk of LV thrombosis after AMI. Patients with an MPI >0.6 after AMI seem to be at a higher risk for thrombus formation.  相似文献   
116.
BACKGROUND & AIMS: The mechanisms by which mutations in the familial intrahepatic cholestasis-1 gene cause Byler's disease (progressive familial intrahepatic cholestasis type 1) are unknown. METHODS: Interactions among the apical sodium-dependent bile acid transporter, the farnesoid X receptor (FXR), and familial intrahepatic cholestasis-1 were studied in the ileum of children with progressive familial intrahepatic cholestasis type 1 and in Caco-2 cells. RESULTS: Increased ileal apical sodium-dependent bile acid transporter messenger RNA (mRNA) expression was detected in 3 patients with progressive familial intrahepatic cholestasis type 1. Paradoxically, ileal lipid-binding protein mRNA expression was repressed, suggesting a central defect in bile acid response. Ileal FXR and short heterodimer partner mRNA levels were reduced in the same 3 patients. In Caco-2 cells, antisense-mediated knock-down of endogenous familial intrahepatic cholestasis-1 led to up-regulation of apical sodium-dependent bile acid transporter and down-regulation of FXR, ileal lipid-binding protein, and short heterodimer partner mRNA. In familial intrahepatic cholestasis-1-negative Caco-2 cells, the activity of the human apical sodium-dependent bile acid transporter promoter was enhanced, whereas the human FXR and bile salt excretory pump promoters' activities were reduced. Overexpression of short heterodimer partner but not of the FXR abrogated the effect of familial intrahepatic cholestasis-1 antisense oligonucleotides. FXR cis-element binding and FXR protein were reduced primarily in nuclear but not cytoplasmic extracts from familial intrahepatic cholestasis-1-negative Caco-2 cells. CONCLUSIONS: Loss of familial intrahepatic cholestasis-1 leads to diminished nuclear translocation of the FXR, with the subsequent potential for pathologic alterations in intestinal and hepatic bile acid transporter expression. Marked hypercholanemia and cholestasis are predicted to develop, presumably because of both enhanced ileal uptake of bile salts via up-regulation of the apical sodium-dependent bile acid transporter and diminished canalicular secretion of bile salts secondary to down-regulation of the bile salt excretory pump.  相似文献   
117.
The effects of statins have been investigated mostly in hyperlipidemic states so far. We analysed blood cholesterol, triglyceride, albumin, fibrinogen and gammaglobulin levels, haematocrite, hemoglobin, erythrocyte, leukocyte and platelet counts, blood and plasma viscosity and erythrocyte rigidity in 12 rabbits fed on a normal diet (chow) which were given 1 mg/kg/day atorvastatin for 4 weeks. Compared to the baseline levels, erythrocyte rigidity (k=0.12+/-0.05 vs. k=0.7+/-0.02) and gammaglobulin levels (1.03+/-0.23 g/dl vs. 0.78+/-0.27 g/dl) decreased significantly (p=0.008 and p=0.025, respectively). Blood lipids, hematological variables, blood and plasma viscosity did not change statistically. Our findings imply that in a normolipemic state, statins given in low doses may improve erythrocyte rigidity without altering blood lipids in short term. Decreased plasma gammaglobulin levels may be reflecting their immunomodulatory effects.  相似文献   
118.
119.

Objective

Changes in serum neurosteroid levels have been reported in stress-related disorders such as anxiety and depression, but not in patients with obsessive-compulsive disorder (OCD). We thus investigated such changes in patients with OCD.

Methods

We compared the serum levels of progesterone, pregnanolone, dehydroepiandrosterone (DHEA), dehydroepiandrosterone sulphate (DHEA-S), cortisol and testosterone in 30 patients with OCD and 30 healthy controls.

Results

When male and female patients were evaluated together, DHEA and cortisol levels were significantly higher in patients with OCD than the control group. When the genders were evaluated separately, DHEA and cortisol levels were higher in female patients than the female controls. The increase in DHEA levels in female patients is likely an effect of the hypothalamic-pituitary-adrenal (HPA) axis. In contrast, cortisol levels in male patients were higher than the control group, while testosterone levels were lower. The increased cortisol and decreased testosterone levels in male patients likely involves the hypothalamic-pituitary-gonadal (HPG) axis.

Conclusion

These findings suggest that neurosteroid levels in patients with OCD should be investigated together with the HPA and HPG axes in future studies.  相似文献   
120.
AIMS: We studied tissue Doppler parameters in patients with atrial fibrillation following acute myocardial infarction, and their relation to P wave durations and P dispersion. METHODS: Echocardiographic examination was performed in 84 consecutive patients with first anterior acute myocardial infarction. In addition to other conventional echocardiographic parameters, the peak systolic (Sm), early diastolic (Em) and late diastolic (Am) velocities were obtained at the lateral corner of the mitral annulus by pulsed wave tissue Doppler. The Em/Am ratio and the ratio of early diastolic mitral inflow velocity to Em (E/Em), which is a marker of diastolic filling pressure, were calculated. Electrocardiogram was recorded from all patients on admission; P wave measurements were also performed. RESULTS: Atrial fibrillation occurred in 20 (23.8%) of 84 patients. The patients with atrial fibrillation had significant reduction of Em (5.6+/-1.5 vs. 8.7+/-2.7 cm/s, p < 0.001), Em/Am (0.61+/-0.27 vs. 0.84+/-0.23, p = 0.001) and Sm (7.1+/-1.0 vs. 8.3+/-1.9 cm/s, p < 0.001) values compared with those without. The E/Em ratio (14.45+/-4.62 vs. 7.47+/-2.79, p < 0.001), P maximum (102+/-11 vs. 95+/-11 ms, p = 0.02) and P dispersion (35+/-7 vs. 26+/-7 ms, p < 0.001) were significantly higher in patients with atrial fibrillation than in those without. In all patients, P dispersion showed significant correlation with Em (r = -0.33, p = 0.002), Sm (r = -0.40, p < 0.001) and E/Em (r = 0.32, p = 0.003). When E/Em > or = 10 was used as cutpoint, atrial fibrillation could be predicted with a sensitivity of 90%, and a specificity of 84%. CONCLUSIONS: The patients with atrial fibrillation following acute myocardial infarction have reduced systolic and diastolic mitral annular velocities and increased E/Em ratio, P maximum and P dispersion values compared to those without. P dispersion is correlated with systolic and diastolic left ventricular function after acute myocardial infarction. The E/Em ratio appears to be a useful parameter for assessing the risk of atrial fibrillation occurrence after anterior acute myocardial infarction.  相似文献   
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