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991.
In therapeutic plasmapheresis using cascade filtration, it is important to maximize albumin recovery while rejecting as many gamma-globulins as possible. Several membrane fractionation techniques were investigated using fresh bovine and human plasma and cellulose acetate filters (PF 100, AKZO). In dead end mode the sieving coefficients were found to decrease as transmembrane pressure increased. This was due to membrane plugging during the course of filtration after about 20 minutes which lead to a rapid increase in transmembrane pressure. In single pass mode the albumin recovery factor generally remains around 40% since the permeate flux is much less than the inlet flow. When strong pulsations (4 to 6 Hz) were superposed on the inlet plasma flow in single pass mode, the albumin sieving coefficient remained at about 0.95 while the permeate flux was increased by 106%. As a result a recovery factor of more than 80% could be sustained for at least 90 minutes without membrane plugging. Therefore pulsatile flow plasma fractionation seems to be an interesting approach to combine continuous operation with high albumin recovery.  相似文献   
992.
Maintenance of the body's perfusion by a total artificial heart (TAH) may result in physiological alterations to the circulatory system. Little has been said about modifications to systemic vascular resistances (SVR) during TAH assistance. This paper reports on two patients implanted with a Jarvik - 70 cc TAH, who died after 1 and 3 days, both with an irreversible drop of SVR related to a complete loss of vascular tone but not related to sepsis. Activation of multiple cascades of inflammation, triggered by the extracorporeal circulation (ECC), is maintained during TAH support. Desperately sick patients might not be able to face the vaso-active situations created by the inflammatory response.  相似文献   
993.
994.
Glomerulopathy and nephrotic syndrome were induced in rats by intravenous puromycin aminonucleoside. Ten days after the injection of puromycin, the animals have developed heavy proteinuria. During this phase, glomerular epithelial cell endocytosis was studied by injecting a conjugate of horseradish peroxidase and poly-L-lysine. This conjugate has been shown to be endocytosed by glomerular epithelial cells. The rats were serially sacrificed from 1 min to 24 h after this injection. Peroxidase was localised cytochemically and observed at light and electron microscopy. The early events of endocytosis in glomerulopathy (namely the binding to the plasma membrane, the membrane invagination and the formation of the early vesicles) were qualitatively similar to those in the normal. The later events (the fusion of the vesicles and their movement within the cells) were inhibited. The results show that puromycin aminonucleoside damages epithelial cell endocytotic activity and affects the later processing of the conjugate within the cells.  相似文献   
995.
996.
Choriocarcinoma is the most malignant tumor of gestational trophoblastic neoplasia. It grows rapidly and metastasizes to the lung, liver, and, less frequently, to the brain. Renal involvement is rare. Magnetic resonance imaging (MRI) is a useful modality to image the affected tissues; it contributes to the evaluation and management of the disease. One case of renal choriocarcinoma with MRI evaluation is reported. Received: 24 February 1997/Accepted: 14 April 1997  相似文献   
997.
Improvement of mouse beta-thalassemia by recombinant human erythropoietin   总被引:3,自引:1,他引:2  
Homozygous beta thalassemic mice received 50 U (1,660 U/kg) of recombinant human erythropoietin (rhEpo) 5 days a week for 2 weeks. Hemoglobin increased from 9.2 +/- 0.6 g/dL to 10.5 +/- 0.4 g/dL (P = .002) and hematocrit increased from 29.2% +/- 0.9% to 34.1% +/- 1.9% (P = .0014). The beta minor/alpha globin chain synthesis ratio increased slightly but significantly between day -4 (0.75 +/- 0.07) and day 4 (0.81 +/- 0.04) (P = .01) and reached a minimum ratio (0.67 +/- 0.03) on day 15 (P = .001), being parallel to reticulocyte counts and to the incorporated trichloracetic acid (TCA)-insoluble radioactivity, therefore parallel to the erythropoietic output in thalassemic mice, as in normal mice. Erythrocyte defects were improved in beta thalassemic mice treated by rhEpo: membrane-associated alpha globin was significantly decreased (P less than .01), thiol group reactivity of ankyrin was significantly improved (P less than .05), spectrin alterations were reduced, and deformability of mouse thalassemic red blood cells was normalized. These results provide experimental criteria for modulating globin chain imbalance necessary for the therapy of human beta thalassemia intermedia, and suggest that rhEpo might be of interest to improve the red blood cell mass and reduce erythrocyte alterations in this disease.  相似文献   
998.
For the empiric management of community-acquired pneumonia, ciprofloxacin (750 mg b.i.d.) was compared with two antibiotics frequently used in this indication, i.e., amoxicillin + clavulanic acid and erythromycin. One hundred and forty-two patients were randomized in this prospective study. Among them, the 63 patients with bacteriologically documented disease were evaluated. Clinical recovery was achieved in 73.3% of patients in the ciprofloxacin group (22/30) versus 81.8% of patients in the amoxicillin + clavulanic acid or erythromycin group (27/33) (non-significant difference). Clinical failures seen with ciprofloxacin were found to be correlated with recovery of Streptococcus pneumoniae. Ciprofloxacin is effective in pneumonia but should be used only in cases where Streptococcus pneumoniae can be excluded as the causative agent.  相似文献   
999.
Seventy-three patients with lip carcinoma were treated from 1970 to 1988 in the Otolaryngology Department of the Beilinson Medical Center. The most common histological type was squamous cell carcinoma which occurred in 68 patients; four tumours were basal cell carcinoma and one acinic cell carcinoma. Carcinoma of the lip is more frequent in males. Nevertheless, the frequency of carcinoma in females in our series was substantially higher than the average reported in the literature. Forty-nine patients were treated surgically and 24 patients were treated by irradiation. Analysis of the results among those treated by surgery and those treated by irradiation shows a difference in tumour local control which was statistically significant (p = 0.025). Surgical treatment is recommended because of the advantage of tumour margin assessment, avoidance of radiotherapy complications and rapid rehabilitation. Two rare cases of carcinoma of the lip in young patients (age under 20 years) are presented.  相似文献   
1000.
Ten cases of pediatric fulminant hemophagocytic syndrome, encountered between 1986 and 1989, are described. They occurred in the summer, and the patients presented with fever, jaundice, hepatosplenomegaly, pancytopenia, coagulopathy, and abnormal liver function. Bone marrow studies revealed infiltration by atypical T-lymphoid cells, rare B immunoblasts, and mature histiocytes with hemophagocytosis. Initially, histiocytic medullary reticulosis was suspected in six cases. The clinical course was characterized by rapid deterioration, with a mean period of 16 days from onset of fever to death. The main causes of death were coagulopathy with multiple organ failure and opportunistic infection. In seven of eight cases studied by serologic assay and Southern blot hybridization, acute or active Epstein-Barr virus (EBV) infection was documented. It is suggested that an atypical or fulminant form of primary EBV infection distinct from classic infectious mononucleosis was prevalent in previously healthy children in Taiwan. Younger age involvement and seasonal clustering were characteristic of the disorder described.  相似文献   
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