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51.
The present study shows that the ability of soluble immune complexes (IC), prepared with human IgG and rabbit IgG antibodies against human IgG, to trigger platelet activation was markedly higher for IC prepared with cationized human IgG (catIC) compared with those prepared with untreated human IgG (cIC). CatIC induced platelet aggregation and adenosine triphosphate release in washed platelets (WP), gel-filtered platelets (GFP), or platelet-rich plasma (PRP) at physiologic concentrations of platelets (3 x 10(8)/mL) and at low concentrations of catIC (1 to 30 micrograms/mL). On the contrary, under similar experimental conditions, cIC did not induce aggregation in PRP, WP, or GFP. Low aggregation responses were only observed using high concentrations of both WP (9 x 10(8)/mL) and cIC (500 micrograms/mL). Interestingly, catIC were also able to induce platelet activation under nonaggregating conditions, as evidenced by P-selectin expression. Cationized human IgG alone did not induce platelet aggregation in PRP but triggered either WP or GFP aggregation. However, the concentration needed to induce these responses, was about eightfold higher than those required for catIC. The responses induced either by catIC or cationized human IgG were completely inhibited by treatment with heparin, dextran sulphate, EDTA, prostaglandin E1, or IV3, a monoclonal antibody against the receptor II for the Fc portion of IgG (Fc gamma RII). The data presented in this study suggest that IgG charge constitutes a critical property that conditions the ability of IC to trigger platelet activation.  相似文献   
52.
Factor V deficiency has been identified in 8 of 8 patients 7--20 yr of age, with Philadelphia-positive (Ph1+) chronic myelogenous leukemia (CML). In these 8 patients, factor V deficiency was not due to hepatic dysfunction, factor V inhibitors, or disseminated intravascular coagulation. In 3 patients, factor V activity rose 10%--12% (0.10--0.12 U/ml) after the infusion of 28--31 ml/kg body weight of fresh frozen plasma (FFP). The rise persisted less than 14 hr. The mean measured postinfusion rise in factor V was 18% of the expected rise calculated from the volume of FFP infused in the patients' plasma volume. In 4 patients, a small transient rise in factor V activity occurred after splenectomy or plateletpheresis. Factor V deficiency was completely corrected after a marked reduction in bone marrow cellularity in 2 patients with Ph1+ CML treated with extensive chemotherapy, total body irradiation, and bone marrow transplantation. Factor V deficiency was retrospectively observed in 6 of 20 patients, ages 20--80 yr, with Ph1+ CML and 3 of 6 patients with other myeloproliferative disorders. The factor V deficiency appears to be associated with the large myeloid- megakaryocytic cell mass characteristic of CML and other myeloproliferative disorders.  相似文献   
53.
In order to compare the long-term safety of flecainide and propafenone,an open label, randomized, parallel group study was performedin 335 patients with paroxysmal atrial fibrillation (n=200)or paroxysmal supra ventricular tachycardia (n=135), and nohistory of heart disease. Patients were treated with an initialdaily dose of flecainide 100 mg (n=72) or propafenone 450 mg(n=63) for paroxysmal supraventricular tachycardia and flecainide200 mg (n=97) or propafenone 450 mg (n=103) for paroxysmal atrialfibrillation. Dose escalations were permitted after 2 attacks,up to a maximum of flecainide 300 mg or propafenone 900 mg.day–1. Follow-up duration was 12 months, or when patientsstopped the treatment as a result of inadequate efficacy oradverse experiences. Twelve patients on flecainide reported 16 cardiac adverse experiences,of whom six discontinued the treatment. Seven propafenone patientshad eight cardiac adverse experiences, of whom five discontinuedthe treatment. Serious proarrhythmic events were infrequent:one case of ventricular tachycardia on propafenone; two casesof atrial fibrillation with rapid ventricular response on flecainide,associated in one patient with pulmonary oedema. An intention-to-treat analysis showed that the probability of12 months' safe and effective treatment of paroxysmal supraventriculartachycardia was 93% for flecainide and 86% for propafenone (P=0·24),whereas in paroxysmal atrial fibrillation it was 77% for flecainideand 75% for propafenone (P=0·72). In conclusion, flecainide and propafenone were safe in the long-termtreatment of patients with paroxysmal supraventricular tachyarrhythmiasand without evidence of clinically significant heart disease.  相似文献   
54.
The Gay Bowel Syndrome   总被引:4,自引:0,他引:4  
Our experience in the management of 260 male homosexuals with coloreetal problems is described. The increased incidence of amebiasis, shigellosis and hepatitis, specific and nonspecific protocolitides, venereal disease and anal warts, is emphasized. It is important to recognize homosexual patients and the conditions to which they are predisposed.  相似文献   
55.
本文旨在就接受治疗的高血压患者经用动态血压监测(ABPM)所评测的诊室外血压控制疗效进行大样本调查分析。对象与方法受试对象为12867例接受治疗的高血压患者,均适应接受ABPM监控,年龄皆≥18岁,平均年龄61.9岁,男性52.4%。其高血压均属原发性高血压,并皆已接受了降压药治疗。尔  相似文献   
56.
Stem Cell Migration and Proliferation During Severe Anemia   总被引:3,自引:2,他引:3  
The pluripotential stem cell (CFU) compartment of marrow and spleen wasevaluated in mice subjected to an intense erythroid stimulus associated withphenylhydrazine-induced anemia. Erythroid hyperplasia occurred in both marrow and spleen. CFU in the marrowgradually declined to approximately 50per cent of control levels (day 5) whiletheir numbers in the spleen increased(fourfold) by day 3 and were maintainedat this level for several days. Thesechanges in numbers of marrow andsplenic CFU were not associated withCFU proliferation. Thereafter, CFU inthe marrow, but not in the spleen, entered active cell cycle. The data suggestthat CFU migrate from marrow to spleenduring the demands of severe anemia.The induction of marrow CFU into cyclefurther suggests a negative feedback,which, perhaps through cell-cell interaction, maintains stem cells at a criticalcompartment size. The failure of splenicCFU to cycle may reflect the converseeffect, i.e. an inhibition on stem cell proliferation in the wake of an expandedstem cell pool.

Submitted on March 17, 1970 Revised on May 14, 1970 Accepted on June 9, 1970  相似文献   
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A commercially available lactobacillus-containing preparation has been used extensively in the treatment of diarrhea but few laboratory tests have been performed to determine the efficacy of this product. The rabbit ileal loop reaction was used here to determine the effect of the lactobacillus preparation and its ingredients on E. coli enterotoxin-induced loop fluid response. Enterotoxigenic E. coli cells grown overnight in shake cultures were washed and resuspended in saline to the original volume. They were then diluted in TSB suspensions of the lactobacillus preparation or its ingredients and injected into ileal loops. E. coli diluted in TSB served as positive controls. Fluid response was measured after 18 hours and the loop fluid ratio (LFR) (ml./cm.) of the lactobacillus preparations was compared to the positive controls. The positive controls always showed a high loop fluid ratio (> 1.1 ml./cm.) and negative saline controls showed no fluid response. The lactobacillus granules and tablets had low LFR's (0.08 and 0.05, respectively). Ingredients (whey, talc, sugar, evaporated milk, mineral oil) had variable LFR's (0.65, 0.78, 1.39, 1.46 and 1.54, respectively). Individual ingredients used to make this preparation show little antifluid response when used separately but the final product exhibits a significant antienterotoxin response.  相似文献   
60.
Cerebral edema may complicate the course of fulminant hepatic failure. Response to conventional therapy has been disappointing. We present a patient with fatal acetaminophen-induced fulminant hepatic failure, with signs and symptoms of cerebral edema, unresponsive to conventional medical therapy. Cranial decompression was carried out. A justification of the need for further evaluation of cranial decompression in such patients is presented.  相似文献   
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