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101.
Morgan  E; Hsu  CC 《Blood》1981,57(5):879-882
Peripheral blood samples from 57 children with newly diagnosed E- rosette-negative, surface-immunoglobulin negative acute lymphocytic leukemia (ALL) were studied for the presence of a leukemia-associated antigen (ALLA). Ficoll-Hypaque separated cells were tested using a rabbit antiserum to human null lymphoblasts and an indirect immunofluorescent assay. The percentage of ALLA-positive cells were compared to the percentage of lymphoblasts determined by differential counts of a Wright-Giemsa-stained smear of a concurrently obtained peripheral blood sample. The mean ratio of percentage of lymphoblasts to percentage of ALLA-positive cells was 0.90. However, in 13 patients, the ratio of percent of ALLA-positive cells to percent of lymphoblasts was equal to or greater than 2:1. In the blood of 6 additional children (5 newly diagnosed, 1 relapsed patient) in whom no morphologically identifiable lymphoblasts were detected. ALLA-positive cells were present (7%-49%). These results indicate that testing for ALLA-positive cells in a sensitive technique for detection of leukemic cells in children with ALLA-positive ALL.  相似文献   
102.
ObjectiveAtrial natriuretic peptide (ANP) is a key regulator in the homeostasis of water excretion and has emerged as an important prognostic marker for symptomatic chronic heart failure (CHF). The stability of ANP represents a crucial factor in assessing its use as a cardiac biomarker. Accordingly, we assessed the stability of ANP in blood samples collected from healthy controls and CHF subjects for a 12 month period.MethodsBlood samples from 10 healthy controls and 12 symptomatic CHF subjects with left ventricular systolic dysfunction were drawn. Determination of plasma ANP was performed by a standardized radioimmunoassay protocol.ResultsThe ANP levels of healthy subjects were 68.5 ± 11.6 pg/mL at baseline and 69.9 ± 17.2 pg/mL at 12 months (p = 0.71). The ANP concentrations of CHF subjects were 199.25 ± 44.8 pg/mL at baseline and 197.83 ± 47.4 pg/mL at 12 months (p = 0.70) respectively.ConclusionANP is a stable molecule with no evidence of degradation when stored at ? 80 °C.  相似文献   
103.
104.
Huntington's disease (HD) is caused by mutated huntingtin (htt), a toxic protein ubiquitously expressed in nervous and non-nervous system tissues. Fragmentation of htt by caspases and further accumulation in cells of protein aggregates contribute to cell dysfunction and death. In the attempt to elucidate whether this mechanism depends on patients' genotype, we analysed the pattern of htt fragmentation, the caspase 3, 8 and 9 activities and their variation in lymphoblasts with heterozygous and homozygous CAG mutation and in controls. Cells homozygous for expanded mutation showed greater amount of mutated fragments than heterozygotes and controls, caspase 3, 8 and 9 activities greater in mutated than control cell lines, after cyanide treatment, the caspase 3 and 8 particularly increased in homozygotes. This data offers a biological explanation to the clinical in-patients evidence of mutation homozygosity associated with more severe phenotype.  相似文献   
105.
Penetrating chest trauma leading to selective coronary artery injury is uncommon. Their incidence is not accurately established because the clinical diagnosis is difficult and the lesion is often revealed only during autopsy. The mortality rate remains high. We report a fatal case of selective right coronary artery injury due to a penetrating wound directed to the right chest.  相似文献   
106.
In the context of a medical surveillance program aimed at preventing cancer risk from exposure to ionizing radiation, we investigated chromosomal damage in peripheral lymphocytes from 37 hospital workers exposed to low levels of ionizing radiation and 37 controls. The micronuleus (MN) assay was used as a biomarker of genetic damage. The influence of confounding factors like smoking status, age and gender was investigated by multiple regression analysis. The results indicated that, overall, MN frequency was higher in exposed workers than in controls, although the difference was not statistically significant. Interestingly, smoking status significantly raised MN frequency among the exposed workers but not among controls. This suggests that smoking can influence chromosomal damage induced in humans by ionizing radiation. Among both exposed workers and controls, MN frequency was found to increase with age. Female gender influenced the increase in MN frequency in the exposed group. Our results suggest that the effect of cigarette smoking should be carefully factored into genetic monitoring studies assessing the risks associated with low level radiation exposure.  相似文献   
107.
Deferiprone (DFO) at the standard daily dose of 75 mg/kg was given to 13 transfusion-dependent patients with thalassemia in whom conventional desferrioxamine (DFX) therapy had proven ineffective and caused adverse side effects. In six patients, serum ferritin and alanine aminotransferase levels decreased significantly and urinary iron excretion increased. In seven patients in whom DFO administration alone was ineffectual, DFX was added at a daily dose of 40 to 50 mg/kg given subcutaneously for 7 to 10 days following transfusion. All patients exhibited a significant decrease in serum ferritin levels and an increase in urinary iron excretion, with alanine aminotransferase levels decreased in four patients. The combined DFX and DFO therapy could represent an effective alternative to conventional DFX therapy not only in nonresponding patients with thalassemia but also, by lowering to less than 25% the DFX dosage, in patients who exhibit important DFX-related side effects.  相似文献   
108.
In older healthy men, aerobic exercise capacity is related to postischemic flow-mediated dilation of the brachial artery (FMD), but corresponding data in a younger population is not available. In addition, whether submaximal aerobic exercise performance also correlates with this kind of vasomotor reactivity is not known. Therefore, in 15 nonsmoking young healthy men [age 27 (5) years; body mass index: 24 (2) kg/m2; mean (SD)] with different levels of ordinary physical activity, but not performing upper-extremity training, we measured FMD at 1 min after reactive hyperemia, and pulmonary oxygen uptake (O2) at ventilatory anaerobic threshold (O2AT) and at peak effort (peak O2) during an incremental exercise on a treadmill. In our participants, FMD was 9.1 (3.4)%, O2AT was 40.72 (5.92) ml/kg per min, and peak O2 was 52.95 (8.13) ml/kg per min. Using bivariate Pearsons correlation, and in separate multivariate regression analyses, O2AT and peak VO2 showed a significant and reasonably good correlation with FMD (r=0.84, P<0.001 and r=0.77, P=0.001, respectively), independent of age, body mass index and serum total cholesterol (=0.77, P<0.001, R2 of the overall model=0.79 and =0.70, P<0.005, R2 of the overall model=0.69, respectively). Our data provide evidence suggesting that in young healthy men a higher submaximal and maximal aerobic exercise performance is associated with a greater FMD of peripheral conduit arteries.  相似文献   
109.
The aim of the present study was to investigate in vivo in a mouse model the stimulation of neoangiogenesis by synovial fluids of patients with rheumatoid arthritis (RA) and to determine the role of tumor necrosis factor (TNF)-α and platelet-activating factor (PAF) in the formation of new vessels. Angiogenesis was studied in a mouse model in which Matrigel, injected subcutaneously, was used as a vehicle for the delivery of potential angiogenic stimuli. Synovial fluids of patients with RA but not with osteoarthritis (OA) were shown to induce neoangiogenesis. Since synovial fluid of patients with RA contained significantly higher levels of TNF-α-like bioactivity and of PAF than that of patients with OA, the role of these mediators was evaluated by using an anti-TNF-α neutralizing monoclonal antibody (mAb) and a PAF receptor antagonist, WEB 2170. When added to Matrigel, anti-TNF-α mAb and particularly WEB 2170 significantly reduced neoangiogenesis induced by synovial fluids of RA patients. Moreover, PAF extracted and purified from synovial fluid induced angiogenesis. These results suggest that the neoangiogenesis observed in rheumatoid synovitis may be due, at least in part, to the angiogenic effect of locally produced TNF-α and PAF.  相似文献   
110.
We investigated the properties of neurons located in the distal forelimb field of dorsal premotor area F2 of macaque monkey using a behavioral paradigm for studying the neuronal discharge during observation (object fixation condition) and grasping of different 3-dimensional objects with and without visual guidance of the movement (movement in light and movement in dark conditions, respectively). The main result is that almost all studied neurons were selective for both the type of prehension and the wrist orientation required for grasping an object. Three categories of neurons were found: purely motor, visually modulated, and visuomotor neurons. The discharge of purely motor neurons was not affected by either object presentation or by the visual feedback of the hand approaching to and interacting with the object. Visually modulated neurons presented a different discharge in the 2 movement conditions, this determining a decrease in selectivity for the grip and wrist orientation in the movement in dark condition. Visuomotor neurons typically discharged during the object fixation task even in the absence of any grasping movement. Nine of them also displayed a different discharge rate between the 2 movement conditions. Congruence was observed between the neuron response during the most effective type of prehension and the neuron response during observation of the object requiring that particular prehension. These results indicate an important role of F2 in the control of goal-related hand movements.  相似文献   
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