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Immunologic studies performed in a case of autoimmune chronic hemolytic anemia with low titer cold agglutinins (1/16) demonstrated that the cold agglutinins corresponded to monoclonal IgG with anti-Pr specificity. This antibody had a large thermal amplitude, being active at 37 degrees C. These unusual characteristics may define a distinct subset of chronic cold agglutinin disease. 相似文献
54.
E Aubeny M Buhler JC Colau E Vicaut M Zadikian M Childs 《The European journal of contraception & reproductive health care》2013,18(4):267-277
Objectives This follow-up study was planned to establish the frequency with which women miss their contraceptive pill, and to observe their behavior when they forget it. In those women who changed from a continuous cycle to an interrupted type of cycle, or vice versa, the study also aimed to evaluate the impact of this change on the pattern of omission of pills. Methods The longitudinal, prospective cohort study included healthy women of child-bearing age for whom a change of pill was being prescribed by their gynecologist. Data were recorded during the 6 months preceding inclusion in the study, and for the 6 months of follow-up; the women were asked to complete a diary in which they recorded the number and exact times of pill omission, and their behavior at each omission. Results A total of 617 gynecologists included 3316 women into the study; of these, a group of 2418 (73%) revisited the same gynecologist at follow-up. The groups who either visited the same or a different gynecologist were similar with respect to age, oral contraception type, omission type and frequency. A large non-compliance rate and women's difficulties in maintaining safe contraception after missing a pill were observed in the group with follow-up. Women were never risk-free when they missed a pill; they turned to numerous sources for discordant or conflicting information; 15% of 'not-forgetting' women at the pre-inclusion cycle recorded at least one omission at the last cycle of the 6-month follow-up period. Omission fluctuations during the observational period make it difficult to designate 'forgetful' or 'non-forgetful' classes of women. Administration of the pill in a continuous cycle, and probably 'study' and 'auto-questionnaire' effects, contributed to an improvement in compliance. In the group taking the continuous cycle pill, the omission number slightly decreased, particularly on the first day and week of the cycle, irrespective of the initial cycle type. Conclusions The importance of the phenomenon of non-compliance rate is confirmed as well as women's difficulties in knowing how to maintain contraceptive safety. The continuous cycle regimen is likely to improve women's compliance during the critical period of the cycle. 相似文献
55.
T2 values in the human brain: comparison with quantitative assays of iron and ferritin 总被引:8,自引:0,他引:8
Chen JC; Hardy PA; Clauberg M; Joshi JG; Parravano J; Deck JH; Henkelman RM; Becker LE; Kucharczyk W 《Radiology》1989,173(2):521-526
Magnetic resonance (MR) imaging with a whole-body imager was performed in 10 fresh, unfixed whole human brains selected randomly from cadavers. All subjects were neurologically intact before death. T2 time constants were measured within the caudate nucleus, putamen, globus pallidus, cortical gray matter, subcortical white matter, and optic radiation. These regions were then excised, and T2 values were measured again with a 1.5-T MR spectrometer. Quantitative assays of iron, ferritin, and protein from these areas were then performed. Iron concentration varied significantly among brain regions, whereas ferritin and protein concentrations were constant among brain regions and among individuals. Neither iron nor ferritin concentration showed any consistent correlation with T2 values. Histologic examination of brain micro-sections with iron- and ferritin-specific stains of demonstrated poor correlation with biochemical assays of ferritin and iron concentrations. Results indicate that T2 values correlate poorly with iron and ferritin concentrations found in neurologically intact brains. 相似文献
56.
Normal and stenotic renal arteries: experimental balloon-expandable intraluminal stenting 总被引:2,自引:0,他引:2
Palmaz JC; Kopp DT; Hayashi H; Schatz RA; Hunter G; Tio FO; Garcia O; Alvarado R; Rees C; Thomas SC 《Radiology》1987,164(3):705-708
Elastic recoil of the vessel wall is a common cause of failure of percutaneous transluminal angioplasty in renal arteries. To oppose such recoil, balloon-expandable metal stents were implanted in artificially stenotic renal arteries in pigs and normal renal arteries in dogs and pigs. The stents were then examined angiographically and histologically at regular intervals. All stents were completely covered with endothelialized neointima in 3 weeks. There was no difference in intimal thickness between the stenotic and nonstenotic renal arteries. A large stent diameter and a large open or nonmetal surface may cause less intimal hyperplasia, but nonturbulent, fast arterial flow is probably the most important factor in ensuring long-term patency of the vessel. 相似文献
57.
Pernes JM; Vitoux JF; Brenoit P; Raynaud A; Parola JL; Roth JP; Angel CY; Fiessinger JN; Roncato M; Gaux JC 《Radiology》1986,158(2):481-485
Thirty-five patients hospitalized for recent angiographically documented arterial occlusion in the legs (27 femoropopliteal arteries and eight grafts) benefited from local fibrinolytic therapy delivered at the site of the occlusion with a 4- or 5-F catheter. This therapy combined a continuous urokinase (UK) infusion of 1,000 U/kg/hour and a lysyl plasminogen (LYS-PLG) infusion of 15 microkatals every 30 minutes. Angiographically confirmed lysis was obtained in 85% of the cases. Only 3% of the patients had major and 6% had minor groin hematomas. Only two patients had concentrations of fibrinogen as low as 100 mg/dl. Intravascular infusion of UK-LYS-PLG is as effective as streptokinase. Its excellent tolerance makes it a good alternative in the treatment of acute ischemia in the lower limbs. 相似文献
58.
Direct sagittal computed tomographic scanning (DSCT) of the shoulder was performed in 42 symptomatic patients, six healthy volunteers, and two cadaver shoulders. Axial CT scanning and double-contrast arthrography with plain radiographs were performed in 41 patients for comparison. DSCT enabled correct identification of 27 of 29 lesions in 24 patients. Seventeen patients had normal shoulders. Axial CT scanning and DSCT together enabled correct identification of all lesions and were markedly superior to plain-film arthrography. DSCT enabled diagnosis of all cases of complete rotator cuff tear plus three cases of incomplete tear and three of rotator cuff atrophy not identified by the other techniques. Axial CT scanning was better than DSCT for diagnosis of Bankart lesions. 相似文献
59.
Urine-compatible polymer for long-term ureteral stenting 总被引:1,自引:0,他引:1
Internal double-J ureteral stents were designed from a urine-compatible polymer (C-Flex), and 35 stents were placed in patients. The overall patency rate for the stents was 80%, with most stent failures occurring before 2 months; the follow-up period ranged from 2 to 16 months, with a mean follow-up for all stents of 5.0 months. Stents were considered patent at last follow-up only if they had been in place for at least 2 months. No migration or fracture of the stents occurred. Physical properties of urine-exposed stents were compared with those of virgin tubing and tubing exposed for 1 year to shelf conditions. Stent patency was optimized by increasing urine flow by increasing the patient's voluntary oral intake, administering prophylactic oral antibiotics, and avoiding placement of stents into grossly bloody or infected collecting systems. 相似文献
60.
Enhancement of chemotactic factor-stimulated neutrophil oxidative metabolism by leukotriene B4 总被引:4,自引:0,他引:4
Leukotriene B4 (LTB4) is a potent primary stimulator of neutrophil chemotaxis, aggregation, and degranulation and induces superoxide production at higher concentrations. In order to determine whether LTB4 modulates neutrophil responses to oxidative stimuli, human neutrophils (PMNs) were incubated with LTB4 prior to stimulation with f-Met-Leu-Phe (fMLP, 10(-7) mol/L), opsonized zymosan (OZ, 250 micrograms/mL), or phorbol myristate acetate (PMA, 32 nmol/L). Superoxide (O2-) production by stimulated PMNs was assessed by the superoxide dismutase-inhibitable reduction of cytochrome c. LTB4 alone did not stimulate O2- production in concentrations below 10(-7) mol/L and had no effect on the O2- assay. In the concentration range of 10(-12) to 10(-8) mol/L, LTB4 did not alter O2- release induced by OZ or PMA. In contrast, LTB4-treated cells demonstrated enhanced O2- production following exposure to fMLP, and in the presence of 10 nmol/LLTB4, generated 180% +/- 41% of O-2 quantities produced by control cells (n = 23). Enhancement was LTB4 dose-dependent, was maximal in the range of 1 to 10 nmol/L LTB4, was not reversed by removal of the lipid from the medium prior to fMLP stimulation, and was not dependent on the presence of Ca++ or Mg++ in the suspending medium. Chemiluminescence of fMLP-stimulated neutrophils was increased to 323% of controls in neutrophils preincubated with 10 nmol/L LTB4. Unlike augmentation of oxidative responses to fMLP seen with other degranulating stimuli, enhancement by LTB4 was not correlated with an increase in 3H-fMLP receptor binding. These results indicate that, in addition to its primary effects on neutrophil function, LTB4 modulates PMN oxidative responses to the chemotactic peptide and, thus, may amplify the release of oxygen metabolites at inflammatory foci. 相似文献