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41.
BACKGROUND: Iron deficiency anemia (IDA) and thalassemia trait (TT) are the most common forms of microcytic anemia. Some discrimination indices calculated from red blood cell indices are defined and used for rapid discrimination between TT and IDA. However, there has been no study carried out in which the validity of all of the defined indices are compared in the same patient groups. Youden's index is the most reliable method by which to measure the validity of a particular technique, because it takes into account both sensitivity and specificity. METHODS: We calculated eight discrimination indices (Mentzer Index, England and Fraser Index, Srivastava Index, Green and King Index, Shine and Lal Index, red blood cell (RBC) count, red blood cell distribution width and red blood cell blood distribution width index (RDWI)) in 26 patients with IDA and in 37 patients with beta TT (betaTT). We determined the number of correctly identified patients by using each discrimination index. We also calculated sensitivity, specificity, positive and negative predictive value and Youden's index of each discrimination index. RESULTS: None of the discrimination indices showed a sensitivity and specificity of 100%. Youden's indices of RBC count and RDWI were the highest with the value of 82 and 80%, respectively. Ninety percent and 92% of the patients were correctly identified with RBC and RDWI, respectively. CONCLUSIONS: Red blood cell count and RDWI are the most reliable discrimination indices in differentiation between betaTT and IDA.  相似文献   
42.
Thrombocytopenia is a common hemostatic abnormality in the newborn infant. The early diagnosis of thrombocytopenia and the underlying primary pathology process play an important role in reducing the risk of severe complications and mortality. We performed a 2-year prospective study of 643 neonates admitted to our neonatology unit to determine the frequency, predisposing factors, and clinical impact of thrombocytopenia. Thrombocytopenia developed in 18.2% of the preterm neonates and 0.8% of the term neonates. Prematurity, sepsis, hypoxia, intrauterine growth retardation, and disseminated intravascular coagulation were identified as predisposing factors for thrombocytopenia. The incidence of complications and mortality were higher in thrombocytopenic infants. Especially the prognosis was worse in cases who had mucosal hemorrhage, without a relation with the degree of thrombocytopenia. The thrombocytopenia occurred by day 2 in 43% of the infants, and resolved by day 8 in 61%. The platelet count nadir occurred by day 2. Since thrombocytopenic infants are at greater risk for bleeding, and the thrombocytopenia itself may have contributed to the high mortality, predisposing factors such as prematurity, infections, hypoxia must be eliminated by prividing better care, giving adequate hygiene of both mother and the baby during the prenatal, natal, and neonatal period.  相似文献   
43.
Hemorrhagic shock causes mucosal damage in intestine and it results in translocation of bacteria to distant organs. In this study, effects of various doses of L-Tryptophan on the prevention of bacterial translocation in hemorrhagic shock induced rabbits were investigated. This study was carried out on six groups, each was consisting of 10 rabbits. While any procedure was conducted on the rabbits in group 1 (as a control group), 1 x 10(10)Escherichia coli isolate were administered rabbits in the other groups by gavage. In groups 3, 4, 5, and 6, hemorrhagic shock was induced. After induction of hemorrhagic shock, 10, 50, and 200 mg/kg L-Tryptophan were intragastrically administered to animals in groups 4, 5, and 6, respectively. Blood and terminal ileum samples were taken to detect bacterial translocation by polymerase chain reaction and mucosal damage by histopathological examination at 24 h after hemorrhagic shock. The occurrence of bacterial translocation increased as well when intestinal bacterial intensity was increased (P < 0.05). The most intensive bacterial translocation was formed in group 3 as a result of the additive effect of hemorrhagic shock to bacterial augmentation. It was observed that bacterial translocation was significantly reduced in groups 5 and 6 that are 50 and 200 mg/kg L-Tryptophan were administered (P < 0.01). Histopathological changes on mucosa and submucosa support these results. As a result, we concluded that augmentation of intestinal bacterial intensity induces bacterial translocation, the addition of hemorrhagic shock to bacterial augmentation makes more excessive translocation and mucosal changes have effective roles in these events. L-Tryptophan decreased the intestinal mucosal damage and bacterial translocation induced by hemorrhagic shock, in a dose-dependent manner.  相似文献   
44.
A 20-year-old pregnant woman was admitted to our department with symptoms of deep venous thrombosis in the left lower extremity and excessive lumbar pain. Low-molecular-weight heparin was administered. She recovered with this treatement, however, severe lumbar pain continued. A lumbar magnetic resonance imageg showed dilated epidural veins compressing the roots and acute thrombosis of the inferior vena cava extending to renal veins. During the same period she had acute deep venous thrombosis in her right leg. An urgent venous thrombectomy was performed. Sciatica and deep venous thrombosis resolved after the operation. Low-molecular-weight heparin was administered until the end of her pregnancy.  相似文献   
45.
OBJECTIVE: To study the anatomical dimensions of the anterior bundle of ulnar collateral ligament and its role in elbow instability. METHODS: We studied 20 elbows of 10 cadavers. Anterior bundle of ulnar collateral ligament was dissected in all elbows and its anatomical length and width were measured. After measuring it, we assessed the role of the anterior bundle of ulnar collateral ligament in the medial elbow joint stability, with the capsule, the radial head and anterior bundle of ulnar collateral ligament being cut. RESULTS: The mean right length of the anterior bundle of ulnar collateral ligament was 21.10 +/- 6.29 mm and the mean left length was 21.70 +/- 5.31 mm. The mean right width of the anterior bundle of ulnar collateral ligament was 12.70 +/- 2.79 mm and the mean left width was 13.90 +/- 2.37 mm. Anterior bundle of ulnar collateral ligament was found to be the main stabilizer of the valgus stress. The anterior capsule and the radial head also make contributions to this stability. However, when anterior bundle of ulnar collateral ligament is cut, the radial head and the anterior capsule fails to maintain the stability against valgus stress. CONCLUSIONS: The anatomical dimensions of the anterior bundle of ulnar collateral ligament are important for a surgeon when graft is used in reconstructing this ligament. Our study is an initiator of this topic and we believe that with larger series, more reliable anatomical measurements can be obtained. We also showed that the anterior bundle of ulnar collateral ligament is the main medial stabilizer of the elbow joint.  相似文献   
46.
Thrombocytopenia and absent radii (TAR) syndrome is a rare disorder. It may be associated with, for example, as cardiovascular, genitourinary, gastrointestinal, skeletal, neurological, ophthalmic, and facial anomalies. Esophageal atresia is also a rare anomaly associated with genitourinary, skeletal, and cardiovascular anomalies, among others. Here, the authors present a child with TAR syndrome and esophageal atresia with tracheoesophageal fistula. This association has been reported in only one other case in literature.  相似文献   
47.
Differentiating between brain abscesses and cystic brain tumors such as high-grade gliomas and metastases is often difficult with conventional MRI. The goal of this study was to evaluate the diagnostic utility of perfusion MRI to differentiate between these pathologies. MRI was performed in 19 patients with rim-enhancing brain lesions (4 pyogenic abscesses, 8 high-grade gliomas, 7 metastases). In addition to standard MR sequences, trace diffusion-weighted MRI with apparent diffusion coefficient (ADC) maps and perfusion-weighted MRI by using a first-pass gadopentetate dimeglumine T2*-weighted gradient echo single-shot echo-planar sequence were performed. Relative cerebral blood volume (rCBV) ratios were obtained via the values of the capsular portions of the lesions and the normal white matter. All the abscesses had markedly hyperintense signals in trace diffusion images, whereas they had significant hypointense signals in ADC images. In perfusion-weighted images, the capsular portions of the abscesses demonstrated low colored areas compared with the normal white matter and the rCBV ratio calculated was 0.76 +/- 0.12 (mean +/- SD). All but two of the cystic tumors showed low signal intensity on trace diffusion-weighted images and high signal intensity on ADC maps. Hyperintense signal was found in two brain tumors mimicking brain abscesses on trace diffusion images. The rCBV values in high-grade gliomas and metastases were 5.51 +/- 2.08 and 4.58 +/- 2.19, respectively. The difference between abscesses and cystic tumors was statistically significant (P = 0.003). Perfusion MRI may allow the differentiation of pyogenic brain abscess from cystic brain tumors, making it a strong additional imaging modality in the early diagnosis of these two entities.  相似文献   
48.
PURPOSE: To compare diffusion-weighted echo-planar imaging (DW) with spin-echo (SE), and fluid-attenuated inversion recovery (FLAIR) sequences in the evaluation of epidermoid cysts (ECs), and to evaluate T2 shine-through effect. MATERIALS AND METHODS: Fifteen patients were imaged prospectively in two different 1.5 T magnetic resonance (MR) units with standard head coils with SE, FLAIR and DW echo planar imaging sequences. The qualitative and quantitative assessments were performed by two radiologists in consensus. Apparent diffusion coefficient (ADC) values were obtained from all ECs. Exponential DW images are obtained in 11 cases to eliminate T2 shine-through effects. The results are analyzed with variance analysis (ANOVA) and Bonferroni t method. RESULTS: FLAIR sequence was superior to T1- and T2-weighted sequences in showing ECs. In 13 cases, the borders of the lesions could be delineated from the surrounding structures with only DW imaging where ECs were markedly hyperintense. The ADC values of ECs are significantly lower than CSF (P < 0.001), and significantly higher than deep white matter (P < 0.01). On exponential DW images, ECs had similar intensity with brain parenchyma showing that the real cause of the hyperintensity of the lesions on trace images is the enhanced T2 effect of the tissue. CONCLUSION: FLAIR sequence is superior to the conventional MR sequences in demonstrating the ECs and DW imaging is superior to other MR sequences in delineating the borders of the ECs. Exponential DW images had shown that the hyperintensity in the trace images are caused by increased T2 effect of the lesion rather than the decrease in ADC values.  相似文献   
49.
We investigated prognostic importance of electrocardiographic (ECG) changes in ischaemic stroke patients without primary heart disease because of the limited evidence. This study consisted of 162 patients (92 male, age 64 +/- 14 years) with first ischaemic stroke presenting to hospital during 18 months. One-month mortality was analysed by means of ischaemia-like ECG changes, long QT and arrhythmia. Ischaemia-like ECG changes were observed in 79% of stroke patients and long QTc in 26% and arrhythmias in 44%. Early mortality rate was 27% (n = 44). Age, ST-segment change and abnormal U wave were univariate predictors of early mortality (each p < 0.05). In multivariate analysis, age > 65 years (OR = 1.4, p = 0.02) and presence of ST-segment change (OR = 2.6, p = 0.01) were only independent predictors. Although sensitivity and specificity of ST-segment change were relatively low to identify patients at risk of death, its negative predictive value was 82%. The ECG changes are frequently seen in selected patients with ischaemic stroke. Regardless of origin, ST-segment change can be a predictor of early mortality.  相似文献   
50.
PURPOSE: To evaluate the functions of the magnocellular and parvocellular pathways in strabismic amblyopia. METHODS: Visual evoked potentials produced by achromatic and chromatic stimuli in 14 children with strabismic amblyopia were compared with those in 14 age-matched control subjects. The achromatic sine-wave grating with low spatial frequency was used to stimulate the magnocellular pathway, whereas the parvocellular pathway was stimulated by the chromatic sine-wave grating (isoluminant red-green) with low and high spatial frequencies. RESULTS: When the achromatic stimuli with low spatial frequency were used, the latencies of the N1 and P1 components and the amplitude of the N1-P1 complex were similar in the children with strabismic amblyopia and the control subjects. There also were no differences between the amblyopic and non-amblyopic eyes of the children with strabismic amblyopia. When chromatic stimuli with low and high spatial frequencies were used, the latencies of the N1 and P1 components were significantly longer and the amplitude of the N1-P1 complex was significantly smaller in the children with strabismic amblyopia than in the control group. When the amblyopic and non-amblyopic eyes of the children with strabismic amblyopia were compared, the latencies of the N1 and P1 components were longer and the amplitude of the N1-P1 complex was smaller in the amblyopic eyes. CONCLUSION: In strabismic amblyopia, the cells in the parvocellular pathway may be more involved, whereas the magnocellular pathway may be relatively spared.  相似文献   
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