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61.
Quality systems and total process control in blood banking 总被引:3,自引:0,他引:3
Blood banking has dramatically changed in the past few years. Is the old business hierarchy and medical model for management still workable? How do we want to organize our work today for success in the future? Implementation of quality systems may seem overwhelmingly complex at this time to many blood banking establishments. However, by methodically adhering to the requirements of organization development described in this review, blood centers can achieve goals of quality improvement and TPC. The FDA and the pharmaceuticals and medical device industries have set the direction and provided guidance to blood establishments. The AABB, American Society for Quality Control, the American Society for Training and Development, and numerous other professional organizations can contribute information and materials. The FDA's document on quality assurance and the CFR are the basic texts guiding the approach presented in this paper. The organization's structure and processes may need to be reengineered to meet the requirements of a culture based on quality and process control. 相似文献
62.
P Hochain P Ducrotté B Paillot J Y Touchais J M Thorel A Petit D Ouvry P Hecketsweiler 《Gastroentérologie clinique et biologique》1992,16(6-7):552-557
Our aim was to assess the efficacy of photodynamic therapy in inoperable patients with small esophageal carcinoma. Eleven patients were treated for squamous cell carcinomas ranging in size from 1 to 3 cm2. Hematoporphyrin (between 3 and 5 mg/kg) was injected intravenously and then the tumor irradiated at endoscopy 72 hours later with a dye laser (630 nm) at an energy of 250 joules/cm2. Complete destruction of the lesion was obtained in 6 cases with negative biopsies at 1 month. In all 6 patients, no recurrence was seen after a median follow-up of 4 months (range: 2-38). Partial destruction of the tumor was obtained in 4 cases while treatment was a complete failure in the last patient. Two instances of mild cutaneous photosensitization occurred. Two patients treated for recurrence after radiotherapy, died of esophageal perforation directly related to the procedure. Photodynamic therapy appears to be a possible effective treatment for esophageal squamous cell carcinoma in inoperable patients when other curative treatment modalities are not possible. 相似文献
63.
The heterogeneity of type IIA von Willebrand's disease: studies with protease inhibitors 总被引:6,自引:0,他引:6
Batlle J; Lopez Fernandez MF; Campos M; Justica B; Berges C; Navarro JL; Diaz Cremades JM; Kasper CK; Dent JA; Ruggeri ZM 《Blood》1986,68(6):1207-1212
The absence of large von Willebrand factor (vWF) multimers from plasma is a characteristic of Type IIA von Willebrand's disease (vWD) and is thought to contribute to the clinical expression of this disorder. Recently, three IIA patients have been reported in whom intermediate and large multimers could be restored if blood were collected in 5 mm EDTA, 6 mmol/L N-ethylmaleimide, and 1 mmol/L leupeptin. This suggested that absence of large multimers resulted from in vitro proteolysis. We have now collected blood from ten Type IIA vWD patients in these inhibitors but were not able to detect large multimers in the plasma of any of them. In addition, intermediate-sized multimers were reduced or completely absent in all. The inclusion of inhibitors in the citrate anticoagulant, as compared to citrate alone, was found to increase the relative proportion of intermediate multimers in some patients but had no effect in others, and in none did it restore large multimers to plasma. The results with platelet vWF were more varied. Four patients showed an absence or decrease of large multimers, whereas in seven patients large multimers were present. When compared with citrate anticoagulant alone, the inclusion of inhibitors in the anticoagulant had little or no effect on the platelet multimeric pattern. 1-Deamino-8- D-Arginine Vasopressin (DDAVP) was administered to six patients from five families. Two patients from one family showed complete correction and a third patient showed almost complete correction of her bleeding time. Two patients showed minimal correction and one showed no detectable correction. An increase in multimer size after DDAVP tended to be associated with correction of the bleeding time. However, in no case did the largest multimers appear in plasma even in patients with complete bleeding time correction. The presence or absence of inhibitors in the anticoagulant had little or no effect on the multimeric pattern after DDAVP. These results indicate that Type IIA vWD is a heterogeneous disorder in which absence of largest and intermediate multimers is an in vivo phenomenon. 相似文献
64.
Comparison between published clinical success of direct resin composite restorations in vital posterior teeth in 1995–2005 and 2006–2016 periods
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Composites are increasing in popularity as restorative materials. This growing role indicates the necessity of studies on their clinical outcome. In this study, clinical studies published on the performance of posterior composite restorations were included except those of less than a 24‐month assessment period. Results of non‐vital, anterior or primary teeth and cervical single‐surface restorations were also excluded. Records about composite type, number of final recall restorations, failure/survival rate, assessment period and failure reasons were analysed for each decade. Overall survival/failure rates for studies in 1995–2005 were 89.41%/10.59% and for 2006–2016 were 86.87%/13.13%, respectively. In 1995–2005, the reasons for failure were secondary caries (29.47%) and composite fracture (28.84%) with low tooth fracture (3.45%) compared with reasons of failure in 2006–2016, which were secondary caries (25.68%), composite fracture (39.07%), and tooth fracture (23.76%). An increase in incidence of composite fracture, tooth fracture and need for endodontic treatment as failure reasons was noted in the latter decade in addition to a decrease in secondary caries, postoperative sensitivity, unsatisfactory marginal adaptation and wear. The overall rates of failure showed little difference, but the causes showed a notable change. This is believed to be a reflection of increased use of composites for larger restorations and possibly changes of material characteristics. 相似文献
65.
Neonatal neutrophils (PMN) show a well-documented defect in chemotaxis that is associated with several abnormalities of PMN structure and function, including deficient surface expression of CR3 (CD11b), a critical adhesion molecule, on chemoattractant-activated PMN. After activation of PMN with additional stimuli including calcium ionophores, we also found deficient surface CR3 (but normal CR1) expression on neonatal PMN suggesting that abnormal signaling mechanisms are not likely to explain the deficient CR3 expression on activated neonatal PMN. Therefore, we hypothesized that deficient surface expression of CR3 on stimulated neonatal neutrophils is caused by a deficiency in total cell content of CR3. We tested this hypothesis using three different methods to compare the total quantity of CR3 in neonatal versus adult PMN. Western blotting of serial twofold dilutions of PMN lysates from five adult and neonatal pairs, using a monoclonal antibody (MoAb) against CR3 (21PM19C), consistently showed diminished CR3 content in neonatal PMN. A sandwich enzyme-linked immunosorbent assay, in which the CR3 heterodimers in PMN lysates were captured by MoAb to the beta-chain, CD18 (R15.7), then detected with a biotinylated MoAb to the alpha-chain, CD11b (anti-Mac-1), showed that neonatal PMN lysates contain about 66% of adult PMN levels of CR3 (P < 0.03; n = 6). PMN fixed with paraformaldehyde and permeabilized with saponin were studied by immunofluorescence flow cytometry to determine total (surface plus intracellular) CR3 content using phycoerythrin-conjugated MoAb to CR3 (anti-Leu15). Mean total cell CR3 content (in relative fluorescence units) was 58 +/- 14 for adult PMN and 27 +/- 6 for neonatal PMN (n = 5; P = 0.013). In each method, total cell content of CR1 was equivalent for neonatal versus adult PMN. We conclude that neonatal PMN are markedly deficient in total cell CR3 content compared with adult PMN. This result provides a primary explanation for deficient CR3 surface expression on activated neonatal PMN that, in turn, may be important in the chemotactic defect of these cells. 相似文献
66.
Groopman JE; Hartzband PI; Shulman L; Salahuddin SZ; Sarngadharan MG; McLane MF; Essex M; Gallo R 《Blood》1985,66(3):742-744
The human T-lymphotropic virus type III (HTLV-III) is the primary cause of the acquired immunodeficiency syndrome (AIDS) and related disorders (ARC). Prior studies have reported that nearly all symptomatic patients with AIDS or ARC manifest antibody to HTLV-III. This observation has engendered efforts to screen for HTLV-III, especially prior to blood donation, with assays for antibody to HTLV-III. We report the first two cases, one with AIDS and one with ARC, that are HTLV-III virus positive but antibody negative. Accurate diagnosis of HTLV-III infection in some cases may require direct virus culture or tests for antigen. In addition, lack of HTLV-III antibody may indicate an atypical clinical course of AIDS. 相似文献
67.
CD34 expression is regulated reciprocally with adhesion molecules in vascular endothelial cells in vitro 总被引:11,自引:1,他引:11
Delia D; Lampugnani MG; Resnati M; Dejana E; Aiello A; Fontanella E; Soligo D; Pierotti MA; Greaves MF 《Blood》1993,81(4):1001-1008
Freshly cultured vascular endothelial cells express the CD34 antigen in a diffuse cell surface pattern with some concentration on microvilli. Expression is downregulated with proliferation in continuous culture and undetectable after nine population doublings but can be maintained by restraining cell proliferation and promoting cell contact. Expression of CD34 at the antigen and mRNA levels on early passage cells is rapidly downregulated by interleukin-1 beta (IL-1 beta), interferon-gamma (INF-gamma), and tumor necrosis factor-alpha (TNF- alpha) under conditions in which these ligands upregulate the adhesion molecules: endothelial leukocyte adhesion molecule 1 (ELAM-1) and intracellular adhesion molecule 1 (ICAM-1). This reciprocal pattern of expression and the topographic distribution of CD34 molecules on the lumenal interdigitated microprocesses of adjacent endothelial cells in vivo suggest that CD34 might have a negative modulating role on adhesion functions of endothelia. 相似文献
68.
Prognostic significance of bcl-2 protein expression in aggressive non- Hodgkin's lymphoma. Groupe d'Etude des Lymphomes de l'Adulte (GELA) 总被引:9,自引:16,他引:9
Hermine O; Haioun C; Lepage E; d'Agay MF; Briere J; Lavignac C; Fillet G; Salles G; Marolleau JP; Diebold J; Reyas F; Gaulard P 《Blood》1996,87(1):265-272
69.
70.
The biochemical and clinical consequences of 2'-deoxycoformycin in refractory lymphoproliferative malignancy 总被引:4,自引:1,他引:4
Grever MR; Siaw MF; Jacob WF; Neidhart JA; Miser JS; Coleman MS; Hutton JJ; Balcerzak SP 《Blood》1981,57(3):406-417
A deficiency of adenosine deaminase, an enzyme important in purine nucleoside catabolism, is associated with a severe combined immunodeficiency disease in children. Inhibition of this enzyme in vitro and in vivo results in an impairment in lymphoblast proliferation. We have investigated the pharmacologic inhibition of this enzyme by 2'-deoxycoformycin in 15 patients with hematologic malignancies. Biochemical consequences of the administration of this agent were closely monitored in erythrocytes, nucleated peripheral blood and bone marrow cells, serum, and urine. A marked rise in erythrocyte dATP was accompanied by a depletion of ATP in those patients exhibiting toxicity. Most patients excreted large amounts of deoxyadenosine but not adenosine in the urine. Serum deoxyadenosine rose in patients demonstrating a marked decrease in cell mass. The biochemical disturbances and clinical toxicity, including hepatic, renal, and conjunctival abnormalities, were usually reversible. Central nervous system toxicity, which potentially was the most serious consequence, was associated with high erythrocyte dATP/ATP ratios and high levels of cerebrospinal fluid deoxyadenosine. In patients with lymphoma and leukemia, objective responses were observed but were short- lived. Patients with chronic lymphocytic leukemia receiving weekly low doses of the drug demonstrated minimal toxicity and some efficacy. The chemotherapeutic potential o 2'-deoxycoformycin, as either a single agent or in combination with Ara-A, merits further exploration. 相似文献