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81.
Gjerset  GF; Martin  PJ; Counts  RB; Fast  LD; Hansen  JA 《Blood》1984,64(3):715-720
We evaluated 37 patients with moderate or severe hemophilia A and six patients with severe factor IX deficiency for clinical or laboratory evidence of immune abnormalities. Patients were assigned to one of four groups according to the type of clotting factor replacement. Twenty patients had received only cryoprecipitate during the two years preceding the evaluation (group I); 11 additional patients were treated predominantly with cryoprecipitate but had also received up to nine bottles of factor VIII concentrate (group II); six patients received factor VIII concentrate (group III); six patients received factor IX concentrate (group IV). There was no clinical or laboratory evidence of immunodeficiency among the 43 patients. The mean absolute number of Th cells was normal in all patient groups, but the mean absolute number of Ts cells was increased compared with controls, both in patients treated with cryoprecipitate and in patients treated with factor VIII or factor IX concentrate. There was no correlation between the Th/Ts ratio and patient age, alanine aminotransferase level, hepatitis serology, in vitro lymphocyte function, or amount of clotting factor administered. Our observations demonstrate that the volunteer or commercial origin of clotting factor replacement cannot fully explain the alterations in lymphocyte subset distribution previously described in patients with hemophilia A.  相似文献   
82.
A statistical analysis of murine stem cell suicide techniques   总被引:1,自引:0,他引:1  
Quesenberry  PJ; Stanley  K 《Blood》1980,56(6):1000-1005
The clinical application of soft agar cloning techniques for granulocyte-macrophage stem cells (CFU-C) has resulted in a number of contradictory reports that may in part be due to an inadequate data base. Growth of murine CFU-C is more reproducible and less variable than that of human CFU-C. We utilized in vivo hydroxyurea suicide of murine marrow CFU-C to address the question of how many experiments are needed to detect a specific difference with a p of less than 0.05. In 66 experiments the mean marrow CFU-C hydroxyurea kill was 23.3%; 6-9 separate experiments were necessary to detaect differences of 25%-30%. In order to be sure that a 25%-30% difference is not present, 15-21 experiments were required. Using a Dec-20 computer, 1000 samples of sample size 3, 4, or 10 were drawn from the 66 experiments; it was found that with 3 experiments and a true value of 23%, the actually observed value was below 10%, 17% of the time, and was over 40% in 10% of the samplings. In a smaller number of experiments similar results were obtained analyzing 3HTdR suicide of pluripotent stem cells and CFU- C. These data could provide a base from which to judge the validity of studies utilizing the CFU-C technique.  相似文献   
83.
The development of ultrasound contrast agents with excellent tolerance and safety profiles has notably improved liver evaluation with ultrasound(US)for several applications,especially for the detection of metastases.In particular,contrast enhanced ultrasonography(CEUS)allows the display of the parenchymal microvasculature,enabling the study and visualization of the enhancement patterns of liver lesions in real time and in a continuous manner in all vascular phases,which is similar to contrast-enhanced computed tomography(CT)and contrast-enhanced magnetic resonance imaging.Clinical studies have reported that the use of a contrast agent enables the visualization of more metastases with significantly improved sensitivity and specificity compared to baseline-US.Furthermore,studies have shown that CEUS yields sensitivities comparable to CT.In this review,we describe the state of the art of CEUS for detecting colorectal liver metastases,the imaging features,the literature reports of metastases in CEUS as well as its technique,its clinical role and its potential applications.Additionally,the updated international consensus panel guidelines are reported in this review with the inherent limitations of this technique and best practice experiences.  相似文献   
84.
The efficacy of a fixed‐dose rituximab schedule was prospectively explored in primary/acute refractory, relapsed or chronic (platelet count >10 × 109/l and ≤50 × 109/l) idiopathic thrombocytopenic purpura (ITP). Patients received two doses of rituximab (1000 mg) on days 1 and 15 and were followed‐up on weeks 1–8, 12, 26, 39 and 52. A total of 122 patients were included in the safety population; efficacy was analysed in 108 patients. Overall response rate (ORR) at week 8, defined as the proportion of patients achieving complete response (CR; platelet count >150 × 109/l) or partial response (PR; platelet count >50 × 109/l) was 44%. Therapeutic response, defined as achieving a response at week 8, with at least a minor response (MR; platelet count >30 × 109/l), sustained up to weeks 26 and 52 and accompanied by a reduction in ITP medications, was achieved in 44% (week 26) and 35% (week 52) of patients, respectively. Treatment was well tolerated with no safety concerns. While this study failed to meet its primary endpoint of an ORR of 50%, the efficacy of two fixed doses of rituximab appear to provide similar efficacy to the standard 375 mg/m2 four‐dose schedule in relapsed/chronic ITP.  相似文献   
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86.

Introduction

Pre-operative donation of autologous blood is a practice that is now being abandoned. Alternative methods of transfusing autologous blood, other than predeposited blood, do however play a role in limiting the need for transfusion of allogeneic blood. This survey of autologous blood transfusion practices, promoted by the Italian Society of Transfusion Medicine and Immunohaematology more than 2 years after the publication of national recommendations on the subject, was intended to acquire information on the indications for predeposit in Italy and on some organisational aspects of the alternative techniques of autotransfusion.

Materials and methods

A structured questionnaire consisting of 22 questions on the indications and organisational methods of autologous blood transfusion was made available on a web platform from 15 January to 15 March, 2013. The 232 Transfusion Services in Italy were invited by e-mail to complete the online survey.

Results

Of the 232 transfusion structures contacted, 160 (69%) responded to the survey, with the response rate decreasing from the North towards the South and the Islands. The use of predeposit has decreased considerably in Italy and about 50% of the units collected are discarded because of lack of use. Alternative techniques (acute isovolaemic haemodilution and peri-operative blood salvage) are used at different frequencies across the country.

Discussion

The data collected in this survey can be considered representative of national practice; they show that the already very limited indications for predeposit autologous blood transfusion must be adhered to even more scrupulously, also to avoid the notable waste of resources due to unused units.Users of alternative autotransfusion techniques must be involved in order to gain a full picture of the degree of use of such techniques; multidisciplinary agreement on the indications for their use is essential in order for these indications to have an effective role in “patient blood management” programmes.  相似文献   
87.
In the study of carotid arteries, modern techniques of imaging allow to analyze various alterations beyond simple luminal narrowing, including the morphology of atherosclerotic plaques, the arterial wall and the surrounding structures. By using CTA and MRI it is possible to obtain three-dimensional rendering of anatomic structures with excellent detail for treatment planning. This paper will detail the role of various imaging methods for the assessment of carotid artery pathology with emphasis on the detection, analysis and characterization of carotid atherosclerosis.  相似文献   
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