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81.
Thrombo-embolic events in coronary and peripheral arteries, and cerebral, pulmonary, portal, hepatic, and deep veins are seen in 27-45% of patients with polycythemia vera (PV). A 79-year-old man was admitted with complaints of pruritus increasing after bath and left upper abdominal pain radiating to left shoulder for two months. On physical examination, ruddy and hyperemic appearances of his face and conjunctiva, tenderness on the left upper quadrant, and splenomegaly were noted. Hemoglobin level was 16.6g/dl, hematocrit 53.8%, white blood cell count 26x10(9)/l, and platelet count 1.032x10(9)/l. Bone marrow aspiration and biopsy revealed hypercellularity, megakaryocytic hyperplasia and dysplasia. The leukocyte alkaline phosphatase score was 190. The levels of serum vitamin B12 and D-dimer were 316 pg/ml and 744 ng/ml, respectively. Arterial O2 saturation was 96%. Red cell mass was measured as 43 ml/kg using radionuclide 51Cr labelled erythrocyte scintigraphy. On cytogenetic analysis, deletion of 20q was found. Computed tomography of whole abdomen showed diffuse splenomegaly and two hypodense areas indicating splenic infarction in 2.5x2 and 3.5x3 cm diameters in subcapsular localization of the spleen. The patient was treated with therapeutic platelet-apheresis, 40 mg/day aspirin, analgesic drugs, and 3g/day hydroxyurea. After 1.5 months, platelet counts dropped to less than 500x10(9)/l and splenic infarcts were not detected on computed tomography. Splenic infarction may be the first evidence of thrombosis in PV. The reduction of platelet counts with platelet-apheresis, anti-platelet drugs, and careful clinical observation may be satisfactory in the treatment of splenic infarction.  相似文献   
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83.
Our objective was to determine if highly active antiretroviral therapy (HAART), previously shown to ameliorate several pathological features of HIV encephalitis (HIVE) in a SCID mouse model, would also reduce additional established pathological features of HIV: cognitive dysfunction, TNF-α, production, and reduced MAP-2 expression. SCID mice with HIVE and control mice inoculated with uninfected monocytes were administered HAART or saline. The HIV pathological features evaluated included astrogliosis, viral load, neuronal apoptosis, MAP-2 expression, mouse TNF-α mRNA production and learning acquisition and retention. HAART reduced the HIV-induced viral load, and the astro- and microgliosis as previously observed; this effect was extended to HIV-induced increases in TNF-α mRNA production. In contrast, although HIV produced the cognitive deficits previously observed and also decreased MAP-2 expression in the area surrounding the injected HIV-infected human monocytes, HAART did not attenuate these effects. Interestingly, there was no neuronal apoptosis evident at the time point reflecting the above pathology. The results of this study combined with previous reports indicate that HAART reduces TNF-α mRNA, viral load and astrogliosis; however, HAART does not improve HIV-induced cognitive dysfunction or MAP-2 decreases. These results suggest that viral load, astrogliosis, TNF- α and apoptosis are not prominent in the pathogenesis of early functional deficits related to decreased MAP-2 expression or cognitive dysfunction in HIVE in SCID mice.  相似文献   
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85.
Hyperthyroidism causes a variety of adverse effects on the cardiovascular system. Left ventricular (LV) asynchrony is defined as loss of the simultaneous peak contraction of corresponding cardiac segments. The aim of this study was to assess systolic asynchrony in patients with overt hyperthyroidism. Asynchrony was evaluated in 27 patients with overt hyperthyroidism and 21 controls. All the patients and controls were subjected to a tissue synchronization imaging (TSI). The time to regional peak systolic tissue velocity (Ts) in LV by the six-basal-six-mid-segmental model was measured on ejection phase TSI images and four TSI parameters of systolic asynchrony were computed. All TSI parameters of LV asynchrony increased in hyperthyroid patients compared to controls: the standard deviation (SD) of the 12 LV segments Ts (35.7±14.4 vs 20.1±10.1, P<0.0001); the maximal difference in Ts between any 2 of the 12 LV segments (111.9±40.7 vs 65.9±30.7, P<0.0001); the SD of the 6 basal LV segments (31.2±18.2 vs 16.8±9.7, P=0.01); and the maximal difference in Ts between any 2 of the 6 basal LV segments (76.6±42.0 vs 44.4±25.7, P=0.005). Patients with overt hyperthyroidism present evidence of LV asynchrony by TSI.  相似文献   
86.
Intraluminal filling defects are occasionally encountered on coronary angiography and often related with coronary thrombi. However, other conditions affecting the coronary arteries may present with similar angiographic findings causing diagnostic uncertainty. Accurate characterization of the angiographic filling defect is critical, particularly in patients planned for a percutaneous coronary intervention (PCI), as diagnosis of a coronary thrombus not only increases the risk of post procedural adverse events but also requires a specific therapeutic approach. In this paper, we report three patients in whom coronary angiography revealed intraluminal filling defects mimicking coronary thrombi. When further investigated with intravascular ultrasound (IVUS) as a part of the planned PCI, the thrombus was excluded and alternate etiology of the filling defect was confirmed in all patients. The angiographic "pseudothrombi" were produced by coronary dissection in one and by heavy calcification within the atherosclerotic plaque in two patients. The use of IVUS allowed accurate characterization of the angiographic filling defect and provided important information to guide management and optimize therapeutic approach.  相似文献   
87.
OBJECTIVE: Crohn's disease (CD) and ulcerative colitis (UC) are chronic inflammatory diseases of the bowel, the causes of which are not fully known. Ethnic differences in disease prevalence, familial aggregation of the disease and studies of twins provide the most important evidence to suggest that genetic factors play a role in the pathogenesis of inflammatory bowel disease (IBD). The aim of this study was to examine the allelic polymorphisms that can determine the immune response levels in tumor necrosis factor alpha (TNFalpha), interleukin-1beta (IL-1B), interleukin-1 receptor antagonist ( IL-1RN) and interleukin-10 (IL-10) genes and to investigate their roles in the inflammatory pathway in IBD. MATERIAL AND METHODS: The study included 120 patients with UC and 70 patients with CD who were diagnosed either endoscopically or histopathologically. The control group comprised 105 healthy individuals who stated that they had never had any bowel disease during their life span. The polymerase chain reaction restriction fragment length polymorphism (PCR-RFLP) method for polymorphisms in the TNFalpha gene at positions -308 and -238, the IL-10 gene at positions -1082 and -627, the IL-1B gene at -511 regions and the variable number of tandem repeat (VNTR) method for polymorphism in the intron 2 of the IL-1RN gene were performed. The results were analyzed on agarose gel electrophoresis. RESULTS: No significant differences were found in the allele and genotype frequencies of the polymorphisms in the IL-1B, IL10, TNFalpha and IL-1RN genes between the patients with UC and CD and controls. CONCLUSIONS: The results suggest that these polymorphisms were not important risk factors in the susceptibility to IBD in Turkish patients.  相似文献   
88.
The aim of the present research was to modify wheat gluten by binding methionine to gluten proteins to develop bread for celiac disease (CD) patients. The highest protein content, wet gluten content, dry gluten content and sodium dodecyl sulphate-sedimentation value were shown by the wheat variety AARI-11, therefore, it was selected for gluten modification. The bound methionine to gluten proteins was found increasing along the reaction time as the reaction proceeds and at a maximum near to 60 minutes and then it starts decreasing. The lowest immunoreactivity of the modified gluten was obtained near to 60 min of reaction at pH 10. The results for immunoglobulin A (IgA) index showed that the serum of each patient had positive IgA index to gliadins from unmodified gluten, but just sera of two patients had positive IgA index to gliadins from modified gluten and when these proteins were digested, the sera of no patient's serum had positive IgA reactivity. Among physical characteristics of breads 2 hours after baking, the specific volume of the modified gluten containing bread (4.13 ± 0.14 cm3/g) was lower than the control bread (4.59 ± 0.21 cm3/g). However, bread made with modified gluten had higher specific volumes than other gluten-free breads. Texture of the modified gluten was also affected by modification. Finally, the gluten content in the modified gluten bread was 79 ppm which is under the limits set by the Codex Alimentarius for food with reduced gluten content should have from 20 to 100 ppm. The study concludes that the incorporation of steric immensity into gluten proteins in order to shun immune recognition is the most promising approach to acquire wheat-based products that are tolerated by CD patients.  相似文献   
89.
Congenital defects involving anomalous chordae of the mitral valve with attachment in the left atrium are an extremely rare finding and may result in valvular insufficiency. Few cases have been reported in the literature with multiple variations in anatomical location and insertion of aberrant chordae within the left ventricle and left atrium. Reported cases have presented with cardiovascular symptoms leading to diagnosis of anomalous mitral valve chordae. We present a case of a young female in which an aberrant mitral valve chorda was an incidental finding on transesophageal echocardiography.  相似文献   
90.
The treatment of choice for well-differentiated thyroid carcinoma is surgery, radioactive iodine ablation and thyroid stimulating hormone suppression [Richard in Cancer 82:375–388, 1988; James et al. in Endocrinol Metab Clin North Am 37(2):497–509]. We report a case with an extensive papillary carcinoma of thyroid gland treated by external beam radiotherapy as a cytoreductive therapy followed by total thyroidectomy. Postoperatively the patient was given radioactive iodine. The patient is free from tumor a year after the treatment.  相似文献   
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