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1.
FM sonography - a signal-processing technique that uses frequency and phase information as well as amplitude data - shows promise in evaluation of patients with diffuse liver disease. In a prospective blinded review of 37 patients with biopsy-proved liver disease and 42 healthy volunteers, FM sonography was clearly superior to traditional amplitude-based (AM) sonography in distinguishing healthy from diseased subjects. Statistically significant differences were seen in accuracy (FM, 98.7%; AM, 84.8%), sensitivity (FM, 97.3%; AM, 70.3%), and negative predictive value (FM, 97.7%; AM, 78.8%). Our data also suggest that current FM sonographic techniques cannot differentiate among histologic findings associated with different hepatic parenchymal abnormalities. It is unclear, therefore, whether FM imaging can reduce the numbers of patients who require biopsy for diagnosis or the frequency of biopsy procedures in patients with known disease.  相似文献   
2.
Prior studies have shown that pneumothorax is one of the more difficult entities to diagnose with digitized radiography. This study was designed to test whether increasing resolution from 1.25 to 2.5 line pairs per millimeter (lp/mm) and image processing (edge enhancement from unsharp masking) would increase accuracy and confidence in the diagnosis of pneumothorax, as well as normal cases and other forms of lung disease. Conventional radiographs were digitized with use of a laser reader and then reformatted as film hard copy. Eleven observers read 35 cases reformatted in three different ways (1.25 lp/mm, 2.5 lp/mm, 1.25 lp/mm unsharp mask). The images with finer resolution (2.5 lp/mm) and unsharp mask images were superior to those with coarser resolution (1.25 lp/mm) for the diagnosis of pneumothorax. There was no difference in diagnostic accuracy for normal patients. For abnormalities other than pneumothorax, the unsharp mask images were significantly worse. Confidence in the diagnosis of pneumothorax and other abnormalities was highest with the finest resolution (2.5 lp/mm).  相似文献   
3.
In this article we present a patient with acute lymphoblastic leukemia (ALL) associated with eosinophilia, in which the eosinophilia preceded a meningeal and bone-marrow relapse of ALL. We analysed the purine and pyrimidine nucleotide content of the eosinophils (92% pure) and compared the nucleotide pattern with that of eosinophils from healthy donors and from patients with eosinophilia not associated with leukemia. The ratios of purine : pyrimidine and of uracil :cytosine nucleotides were decreased compared with those in eosinophils from healthy donors and from patients with eosinophilia with other aetiologies. The total nucleotide concentration was increased, especially the concentration of UDP-sugars and pyrimidine nucleotides.

The decrease in these ratios and the increase in concentration of the nucleotides and the UDPsugars were also detected in leukemic cells of patients with ALL (de Korte et al., Leukemia Res. 10, 389–396 (1986)) compared to normal lymphocytes. We suggest a malignant character of the eosinophils in our patient with ALL associated with eosinophilia, in contrast with the nonmalignant state suggested previously for these cells.  相似文献   

4.
A group of 5,000 patients, suspected of haemolytic anaemia, were investigated with molecular genetic methods for deletion types of alpha-thalassemia. In 776 (15.6%) patients a deletion of one or more alpha-globin genes was found. The same group of patients was also investigated for abnormal haemoglobins and beta-thalassaemia. In about 30% of the patients either an alpha-thalassaemia, an abnormal haemoglobin, a beta-thalassaemia, or a combination was diagnosed. In a group of patients with a haemoglobinopathy, the frequency of alpha-thalassaemia was much higher (i.e. 33%) than in individuals without haemoglobinopathy. Preselection of the patients based on the presence of microcytic erythrocytes and/or a decreased ADW0.5 of the erythrocytes gave a high incidence of false-negative and false-positive results. Therefore, haemoglobin examination should not be restricted to protein chemistry, but should include molecular genetic investigations for deletion types of alpha-thalassaemia.  相似文献   
5.
Background: Thrombotic complications are common in patients with endstage renal disease and contribute substantially to the morbidity and mortality in this population. The aim of the present study was to: I) determine the prevalence and the extent of hypercoagulability in patients undergoing dialysis treatment by measuring parameters that directly reflect thrombin concentrations, ii) assess changes in coagulation status during haemodialysis (HD); iii) quantify the relative impact of heparin, dialysis and their combined effects on coagulation status and iv) detect factors that modify coagulation haemostasis in dialysis patients. Method: A total of 39 patients (HD: n=29, CAPD: n=10) was analysed for procoagulatory and fibrinolytic activity determined by measurements of partial thromboplastin time, prothrombin fragments F1+2, thrombin-antithrombin complexes and D-dimer concentrations. HD patients were investigated prior to and during dialysis. A subgroup of patients was infused heparin alone without dialysis or was dialysed without heparin administration. Furthermore, subgroup and correlation analyses were performed for the type of dialysis (HD vs CAPD), dialyzer and shunt, Kt/V, underlying disease and treatment with recombinant erythropoietin (rhEPO). Results: Baseline levels of all parameters-procoagulatory and fibrinolytic- were substantially elevated in all patients, but to a higher degree among those on CAPD. Moreover, haemodialysis treatment increased procoagulatory markers even further, suggesting stimulated coagulation and/or insufficient anticoagulation during dialysis. However, after 3 h of dialysis thrombin concentrations, determined by quantification of prothrombin fragments, were inversely correlated with Kt/V. Selective heparin infusion diminished procoagulatory activity only slightly and incompletely, whereas HD without heparin resulted in excess thrombin accumulation. Finally, subgroup analyses revealed more pronounced thrombin formation among patients treated with polysulfon dialyzers, whereas erythropoietin dosage was positively related with lower procoagulatory activity. Conclusion: A majority of patients on dialysis are in a hypercoagulable state, which is further aggravated by the haemodialysis procedure itself and may not be sufficiently controlled with current anticoagulation regimens. Intensified heparin treatment and the use of rhEPO are likely to improve coagulation haemostasis, whereas the type of dialyzer should be considered as a relevant procoagulatory factor.  相似文献   
6.
Rat lenses with experimentally induced cataract (either by naphthalene or by streptozotocin) were analyzed biochemically. Both noxae had some effects in common. Water-soluble protein and aldose reductase activity decreased, and glucose-6-phosphate dehydrogenase, phosphofructokinase and glutathione reductase activity increased. A specific effect of streptozotocin was the rise in glucose, fructose and sorbitol. A specific effect of naphthalene was increased amounts of water-insoluble protein.  相似文献   
7.
Acute effects of lamotrigine (BW430C) in persons with epilepsy   总被引:26,自引:19,他引:7  
Sixteen epileptic patients took single doses of lamotrigine, 120 mg or 240 mg. Six photosensitive patients showed reduction (with abolition in two) in photosensitivity after lamotrigine administration. Five subjects with frequent interictal spikes showed reduction in spike frequency over 24 h after lamotrigine administration. The half-life (t1/2) of lamotrigine in subjects taking sodium valproate was prolonged, whereas the t1/2 in subjects taking carbamazepine and/or phenytoin was reduced. The area under the curve of co-medication plasma levels was not affected by a single dose of lamotrigine. Five patients reported mild and generally transitory side effects; some of which represented exacerbation of preexisting complaints.  相似文献   
8.
Proactive rodents show a larger behavioral response to apomorphine (APO) than reactive copers, suggesting a more sensitive DA system in proactive individuals. Previously, chicks from a high feather pecking (HFP) and low feather pecking line (LFP) have been suggested to display a proactive and reactive coping strategy, respectively. Therefore, at approximately 4 weeks of age, the behavior of 48 LFP and 48 HFP chicks in response to an APO injection was studied using an open field. Another objective of the present study was to determine whether behavioral variation (in an open field) between HFP and LFP birds, after APO injection, is also reflected by variation of D(1) and D(2) receptor densities in the brain. Receptor binding capacities were assessed by measuring specific binding of tritiated D(1) and D(2) receptor ligands in different regions of the brain of control HFP and LFP chicks. In the present study, it is shown that indeed HFP chicks display a more enhanced behavioral response to acute APO treatment (0.5 mg/kg BW) than LFP birds in an open field. This difference was not reflected by variation of D(1) and D(2) receptor densities in the brain between both lines.  相似文献   
9.

Objective

To investigate the relation between donor characteristics and TRALI incidence.

Background

Transfusion-related acute lung injury (TRALI) is a potentially fatal complication of transfusion. In pre-clinical studies and several clinical studies, TRALI has been related to loss of product quality during red blood cell (RBC) storage, called the “storage lesion”. Donor characteristics, as for example age, genetics and life style choices influence this “storage lesion”. We hypothesized that donor sex, age and blood type is related to TRALI incidence.

Methods/materials

We performed a secondary analysis of two cohort studies, designed to identify TRALI risk factors by matching TRALI patients to transfused controls. We obtained donor sex, age and blood type from the Dutch Blood Bank Sanquin and investigated TRALI incidence in patients who were exposed to a certain donor characteristic. We used Kruskal-Wallis testing to compare the number of transfused products and Chi2 testing to compare proportions of TRALI patients and transfused control.

Results

After implementation of the male-donor only plasma strategy, patients received more transfusion products from male donors. However, we did not detect a relation between TRALI incidence and donor sex. Both TRALI patients and transfused controls received mainly products from donors over 41 years old, but donor age did not influence TRALI risk. Donor blood type, the transfusion of blood type-compatible and blood type-matched products also had no influence on TRALI incidence.

Conclusion

We conclude that in two cohorts of TRALI patients, donor age, donor sex and donor blood type are unrelated to TRALI.  相似文献   
10.
Mean arterial pressure (MAP), heart rate (HR), plasma epinephrine (E), plasma norepinephrine (NE), and plasma corticosterone (CORT) were measured in 3-month- and 24-month-old male Wistar rats exposed to a conditioned emotional stress response (CER) paradigm and a conditioned defensive burying (CDB) paradigm. In the CER situation blood samples were taken during reexposure to the training environment one day after a single inescapable footshock (0.6 mA, AC for 3 s) had been administered. In the CER paradigm the young rats displayed passive behavior (immobility) accompanied by an increase in plasma levels of CORT and E, whereas both the control and conditioned animals showed increased NE responses. Previously shocked aged rats exhibited an attenuated plasma NE response, whereas levels of E remained elevated to a greater extent. Aged animals showed elevated basal levels of CORT one day after footshock administration. Stress-induced immobility was preserved in the aged rats. These animals had an increase in basal MAP values and a decrease in basal HR values compared to young ones. In the CDB paradigm, rats were exposed to a nonelectrified probe 1 day after the repeated shock (2 mA/contact) procedure. Young rats displayed defensive burying accompanied by increments in MAP, HR, CORT, and NE. The aged animals showed similar hormonal, autonomic, and behavioral stress responses. Thus, the age-related alterations in neuroendocrine and autonomic response patterns are apparent in stressed animals during behavioral passivity in absence of control (CER) rather than during active control (defensive burying).  相似文献   
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