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101.
Hasegawa DK; Bennett AJ; Coccia PF; Ramsay NK; Nesbit ME; Krivit W; Edson JR 《Blood》1980,56(4):585-595
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
102.
103.
A retrospective analysis was made of the data on 60 patients with stage T1 glottic carcinoma (43 T1a, 17 T1b) who received radiation therapy and 17 patients with T1a disease who underwent laser excision as the primary treatment modality. Patients who received radiation therapy achieved 3- and 5-year actuarial local control rates of 92% and 89% for T1a and 77% and 77% for T1b disease, respectively. In patients who underwent laser excision (all with T1a disease), the 3-year local control rate was 77%. Of the 42 evaluable irradiated T1a patients, 31 (74%) had a normal to near-normal voice, eight (19%) had mild or intermittent hoarseness, and three (7%) had persistent hoarseness. Of the 13 evaluable patients in the laser-excision group, four (31%) had a normal to near-normal voice, five (38%) had mild or intermittent hoarseness, and four (31%) had persistent hoarseness. The difference in the quality of voice between these two groups is statistically significant (P = .012), although the ultimate local control rate after salvage therapy for irradiated patients (97%) was similar to that for laser-excision patients (94%). 相似文献
104.
Visual identification of bacterially contaminated red cells 总被引:1,自引:0,他引:1
There have been increasing numbers of reports of transfusion-acquired Yersinia enterocolitica bacteremia (including several fatal cases). Fifteen units of whole blood were inoculated with various concentrations of Y. enterocolitica serotype 0:3 and processed into AS-3 preserved red cells (RBCs). Consistent growth of the organism was found at inoculum concentrations greater than or equal to 10 colony-forming units per mL. In all 13 units of RBCs that supported the growth of Y. enterocolitica, a darkening in color (due to hemolysis and a decrease in pO2) was observed in the bag. The attached sample segments, which were sealed from the main unit, remained sterile and did not darken. This color change was apparent in all the contaminated units by Day 35, which was 1.5 to 2 weeks after the bacteria were first detected in cultures of the blood. Hence, by comparison of the color of the segment tubing with that of the unit itself, units grossly contaminated with Y. enterocolitica can be identified prior to transfusion. Moreover, review of photographs on file at the Centers for Disease Control revealed this dramatic color change in 2 units of blood that caused transfusion-transmitted sepsis (Enterobacter agglomerans and an unidentified gram-negative bacillus, not Yersinia sp.), which demonstrated that the color change was not limited to Y. enterocolitica. This method of visual identification of contaminated units of blood could decrease the incidence of posttransfusion bacterial sepsis. 相似文献
105.
ME Pichichero S McLinn HA Rotbart MA Menegus M Cascino BE Reidenberg 《Pediatrics》1998,102(5):1126-1134
OBJECTIVE: To characterize the acute clinical course and economic burden of nonpolio enteroviral (NPEV) illness in the summer/fall season as seen in private pediatric practice. METHODS: We prospectively studied 380 children aged 4 to 18 years with systemic NPEV syndromes presenting to private suburban pediatric practices. Seventy-three asymptomatic controls were concurrently enrolled. Clinical diagnosis of NPEV illness was based on the presence of fever plus at least one of the following: headache and stiff neck (n = 2); myalgia and malaise (n = 105); nonpuritic maculopapular rash (n = 10); papulovesicular stomatitis (n = 214); papular rash of the hands, feet, and mouth (H/F/M) (n = 30); or pleurodynia (n = 11). Study participants were enrolled during a 4-month time span (July-October, 1994) and followed daily for 14 days. A parent symptom diary card and twice weekly phone contacts by study nurses characterized the illness to include the frequency of health care contacts, the necessity for laboratory tests, medication use, and school/work absenteeism. RESULTS: Three hundred seventy-two (98%) children completed the study; 122 (33%) of the patients were confirmed to be infected with NPEV. Confirmed NPEV infection was more frequently observed in Rochester, NY (85/147 = 58%) than in Scottsdale, AZ (32/224 = 14%). The age group 4 to 12 years comprised 79% to 90% of the enrollees, depending on the syndrome. Median duration of illness and median number of missed days of school/summer camp/work for the enrolled patients was: meningitis (7 days ill, 2 days missed), myalgia/malaise (9 days ill, 3 days missed), rash (6 days ill, 4 days missed), stomatitis (7 days ill, 2 days missed), H/F/M (7 days ill, 1 day missed), and pleurodynia (8 days ill, 3 days missed). Direct medical costs varied from $69 per case to $771 per case and indirect costs, attributable primarily to parent missed work and/or sick-child care, varied from $63 per case to $422 per case for H/F/M and meningitis, respectively. In households, H/F/M spread to 50% of siblings and 25% of parents. CONCLUSIONS: In our study population, NPEV infection: 1) caused sufficient illness to prompt physician visits in summer and fall; 2) occurred more frequently in 4 to 12 year olds than in adolescents; 3) produced various clinical syndromes concurrently during the same months in the same season of a given year; 4) varied in occurrence geographically; 5) was characterized by numerous symptoms of longer duration than previously recognized; and 6) produced a significant economic impact by generating both direct and indirect costs. 相似文献
106.
Cytotoxic T lymphocytes specific for I region determinants do not require interactions with H-2K or D gene products 下载免费PDF全文
P Billings S Burakoff ME Dorf B Benacerraf 《The Journal of experimental medicine》1977,145(5):1387-1392
Gene products coded for by the major hisocompatibility complex (MHC) can serve as target antigens for cytotoxic T lymphocytes (CTL) (1). A variety of test systems are available which have yielded information consistently reinforcing the importance of this complex of genes in the generation and effector phases of the cytotoxic immune response. Originally, it was shown that allogeneically-induced CTL had specificity primarily for the products of the K and D loci of the mouse H-2 complex (2). More recently this has also been found to be the case for xenogeneic immunizations (3,4). Additional examples of T cell-mediated lysis have been reported involving viral-infected or chemically- modified syngeneic stimulating and target cells in which homology at H-2K or H-2D was required between the responding and target cells for appreciable lysis to occur (5-7). Moreover, CTL specific for minor histocompatability antigens are able to lyse only target cells bearing these membrane antigens and sharing a common H-2K or H2-D gene product with the effector (8,9). Two hypotheses have been proposed to explain the requirement for H-2 identity between effector and targets in these systems. CTL may recognize new antigenic determinants created by the interaction of the modifier with syngeneic K and D gene products. Alternately, a dual recognition system my exist, requiring an antigen-specific receptor as well as a second receptor with specificity for homologous H-2K or H-2D determinants (5). Neither model can be excluded at this time. The I region also contains genes coding for histocompatibility loci since animals differing at the I-A or I-C regions of the H-2 complex reject skin grafts (10-12), though less rapidly than mice differing at the H-2K or H-2D regions, Also CTL can be generated to I region determinants but less efficiently than CTL specific for H-2K or H-2D gene products (12-14). The question can therefore be raised, whether the I region minor histocompatibility loci function independently from the H-2K or H-2D loci or whether I region-specific cytolysis requires the participation of H-2K or H-2D gene products of the target cell. This communication illustrates the generation of CTL showing specificity for I region determinants in primary mixed lymphocyte cultures. Further, we demonstrate by genetic analysis and byt eh use of speficit alloantisera that CTL directed to Ia determinants (a) do not see these antigens as modifications of H-2K or H-2D gene products but as independent gene products coded for by the I region, and (b) they do not require interaction with target cells bearing the same H-2K or H-2D gene product as the effect CTL. 相似文献
107.
The I-J subregion codes for determinants on suppressor factor(s) which limit the contact sensitivity response to picryl chloride 下载免费PDF全文
The cell-mediated immune reactivity (CMI) of mice to contact chemicals such as picryl chloride (PCI) is influenced by thymus-derived suppressor T lymphocytes (1,2). The development of these suppressor T lymphocytes is stimulated by the intravenous administration of 2,4,6-trinitrobenzene sulfonic acid (TNBS). Zembala and Asherson have further demonstrated that a specific suppressor factor(s) can be detected in the supernates of cultured suppressor T cells. This factor suppresses the transfer of contact sensitivity (CS) to PCl (1,2). In experiments reported elsewhere (3), we have shown that the PCl suppressor supernates of Zembala and Asherson can also suppress the development of contact sensitivity to PCl. The immunochemical analysis of suppressor factor (SF) operative in the CS response to PCl has revealed many similar properties (3) to other suppressive moieties functioning to limit the plaque-forming cell (PFC) response to dinitrophenylated-keyhole limpet hemocyanin (DNP-KLH) as well as the strict antigen specificity of each respective suppressive factor, suggested that there might be a common origin of these substances. Indeed, in each case these respective factors were found to bear determinants controlled by the H-2 gene complex (4,5). Recently, in selected systems, the I-J subregion has been found to code for the Ia determinants present on suppressor cells (6) and suppressor factors (4,5). In accord with these findings, we report that antigen-specific SF which limit the CS response to PCl bear I-J determinants, implying that analogous suppressive regulatory mechanisms in CMI as well as antibody responses may be determined by genes of one subregion of the H-2 complex. 相似文献
108.
P Debre C Waltenbaugh ME Dorf B Benacerraf 《The Journal of experimental medicine》1976,144(1):277-281
Previous reports from our laboratory have demonstrated the stimulation of specific suppressor T cells in genetic nonresponder mice after immunization with the terpolymer of L- glutamic acid, L-alanine, and L-tyrosine (GAT) (1,2) and with the copolymer of L-glutamic acid and L-tyrosine (GT) (3-5). These findings raise two important questions: (a) do the specific suppressor T cells inhibit an antibody response which would otherwise develop in nonresponder mice; and, (b) can specific helper T cells inhibit an antibody response which would otherwise develop in nonresponder mice; and, (b) can specific helper T-cell activity be detected in these animals. Responsiveness appears to be completely dominant over suppression in (responder x suppressor)F(1) hybrids, therefore, we have been unable to detect suppressor cells in these hybrids after conventional immunization with GAT (2). However , using special conditions of antigen administration, GAT helper activity could be demonstrated in nonresponder DBA/1 (“suppressor”) mice. Thus, GAT-specific helper activity was not detected in these nonresponder animals after immunization with GAT irrespective of the adjuvant used, but could be stimulated by macrophage-bound GAT or by GAT complexed with methylated bovine serum albumin GAT-MBSA (6). In the current report we have taken advantage of the fact that suppressor T-cell activity is more sensitive to cyclophosphamide treatment than T-cell helper activity (7) to demonstrate the presence of GT-specific helper activity in “nonresponder” BALB/c mice. We describe: (a) the dose of cyclophosphamide and conditions of treatment which inhibits the well-documented stimulation of specific suppressor T cells in BALB/c mice injected with GT previous to immunization with GT-MBSA, and (b) the ability of cyclophosphamide to permit the development of primary PFC responses to GT in these “nonresponder” mice. These cyclophosphamide-induced responses are not characterized by the high levels of antibody detected in genetic responder animals. 相似文献
109.
Richter's syndrome with different immunoglobulin light chains and different heavy chain gene rearrangements 总被引:2,自引:0,他引:2
van Dongen JJ; Hooijkaas H; Michiels JJ; Grosveld G; de Klein A; van der Kwast TH; Prins ME; Abels J; Hagemeijer A 《Blood》1984,64(2):571-575
In a patient with Richter's syndrome, the chronic lymphocytic leukemia (CLL) expressed lambda, mu, and delta immunoglobulin (lg) chains and the non-Hodgkin lymphoma (NHL) kappa, mu, and delta lg chains. The difference in lg light chain expression suggests that the CLL and NHL are independent malignancies, or that the oncogenic event occurred in a B cell differentiation stage after the heavy chain gene rearrangements but before the selection of the light chain. Analysis of DNA by Southern blotting revealed that the lg heavy chain genes of the two malignancies were rearranged in a different way. We therefore conclude that in this patient the NHL cannot be regarded as a progression of the CLL but should most likely be considered as an independent B cell malignancy, which arose in a susceptible host. 相似文献
110.
Pharmacokinetics of midazolam in Vietnamese subjects 总被引:2,自引:0,他引:2
KR BALSON DJ MORGAN BH RICHMOND ME McALINDON SL ELLIOTT ND YEOMANS 《Journal of gastroenterology and hepatology》1996,11(10):1177-1180