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121.
122.
ObjectiveTo observe and assess the compliance to sulfadoxine-pyrimethamine (SP) one and a half years after phasing out chloroquine (CQ) in Mkuranga District, Coast region, Tanzania.MethodsA randomly controlled baseline community study was conducted in rural areas of Mkuranga district, Tanzania. Semi-structured questionnaire consisted of open-and closed -ended questions including home stocking, home use, last fever episodes and treatment of underfives with malaria using CQ or SP.ResultsThe prevalence of fever or reported fever rate during the last 48 hours by their mothers or guardians was high (70%). Of all 117 blood samples, only 8 children after drug analysis were found to have CQ and 13 had SP concentrations within their blood respectively. None of these blood drug levels were above therapeutic ranges.ConclusionsCommunity interventions are urgently needed in rural communities and should specifically target households nucleus on early malaria fever recognition and provision of recommended antimalarials for the sick underfive children. However, sadly, there was an increase in underweight and undernourishment in the study areas, probably because of malaria in the area and poverty which are associated with poor nutrition in these youngsters.  相似文献   
123.
Video recording techniques have been used in educational settings for a number of years. They have included viewing video taped lessons, using whole videos or clips of tapes as a trigger for discussion, viewing video recordings to observe role models for practice, and being video recorded in order to receive feedback on performance from peers and tutors. Although this last application has been in use since the 1960s, it has only been evaluated as a teaching method with health care professionals in the past 10 years and mostly in the areas of medical and counsellor education. In nurse education, however, use of video recording techniques has been advocated without any empirical evidence on its efficacy. This study has used nursing degree students and nurse educationalists to categorize statements from four cohorts of students who took part in a 12-day clinical supervision course during which their interpersonal skills were recorded on videotape. There were two categories: positive and negative/neutral. Analysis of the data showed that between 61% and 72% of the subjects gave an overall positive categorization to the statements in the questionnaire. Chi-square tests were significant for all groups in both categories. This suggests that both nursing students and nurse lecturers thought that course participants' statements expressed a positive belief that video tape recording is useful in enhancing students' ability to learn effective interpersonal skills in clinical supervision.  相似文献   
124.
The records were reviewed of 58 patients receiving transplants in Seattle with unmanipulated marrow from HLA-identical siblings during the accelerated phase (AP) of chronic myeloid leukemia. Variables examined for association with survival and relapse included the interval from diagnosis to transplant, the reasons for categorization as AP, age, regimen, and cytomegalovirus serology. Four patients relapsed. The 4-year probabilities of survival, relapse-free survival, nonrelapse mortality, and relapse were 0.49, 0.43, 0.51, and 0.12, respectively. After completion of the stepwise multivariate analysis, age less than 38 years and categorization as AP solely on the basis of chromosomal abnormalities emerged as being independently significantly associated with improved survival. The 4-year probability of survival for the 16 patients categorized as AP because of chromosomal abnormalities and receiving transplant less than 1 year from diagnosis was 0.74. The low probability of relapse in these patients suggests that more aggressive preparative regimens are not indicated for patients receiving transplants in AP because of the increased risk of transplant-related mortality.  相似文献   
125.
Patients with Hb SC disease were found to have microcytic and hyperchromic red cell indices despite mild reticulocytosis. Iron deficiency anemia was ruled out by the finding of normal serum ferritin levels. In order to determine whether the microcytosis was due to coexistent alpha-thalassemia, restriction endonuclease mapping was performed on genomic DNA extracted from peripheral blood leukocytes. Patients with Hb SC disease had microcytic indices despite the presence of a full complement of four alpha-genes (alpha alpha/alpha alpha), suggesting that the microcytosis may be due to cellular dehydration (or xerocytosis), since the mean corpuscular hemoglobin concentration in Hb SC disease patients was significantly higher than in controls. This possibility was investigated further by the determination of RBC cation content. RBC Na levels were similar in SC and normal red cells. Hb SC RBCs, however, had significantly reduced K levels. These findings show that RBC cation content, and thus cell water, is decreased in Hb SC disease. The decreased RBC K level in the presence of normal cellular Na concentration suggests selective K loss that is not due to inhibition of the Na K pump. Ouabain-insensitive K+ efflux was increased to four times normal in SC cells. Cell dehydration was confirmed by the demonstration of increased high-density RBCs on discontinuous Stractan density gradients and by osmotic gradient ektacytometry. Cellular dehydration and its sequelae were worse in CC erythrocytes and milder in AC cells than in Hb SC red cells. Taken together, these data indicate that in Hb SC disease the RBCs are severely dehydrated and typically microcytic and hyperchromic. Hb SC RBCs seem to be dehydrated due to selective K loss. These findings suggest a functional interrelationship between Hb SC, the red cell membrane, and cation regulation.  相似文献   
126.
Zhong  RK; Donnenberg  AD; Rubin  J; Ball  ED 《Blood》1994,83(8):2345-2351
Autologous bone marrow (BM) transplantation after high dose therapy is widely used to treat acute leukemia, lymphoma, and selected solid tumors. In studies of BM purging with chemical agents, monoclonal antibodies (MoAbs), or other agents, the emphasis has been on the efficacy of tumor cell removal and sparing of hematopoietic progenitor cells. Two commonly used methods of BM purging for patients with acute myeloid leukemia have been the drug 4-hydroperoxycyclophosphamide (4- HC) and (MoAbs) directed to myeloid antigens such as CD14, CD15, and CD33. Although both methods of BM purging have potent activity against leukemia cells, 4-HC is also quite toxic to normal hematopoietic progenitor cells in the same concentrations that are used to deplete leukemia cells. To further characterize the cellular composition of BM after purging, we examined the effects of MoAbs plus complement and 4- HC on cells of the lymphoid lineage in the BM. 4-HC exerted a concentration-dependent cytotoxicity on clonogenic T lymphocytes, natural killer (NK) cells, and lymphokine (interleukin-2)-activated killer (LAK) cells, whereas the anti-CD14 and anti-CD15 MoAbs had little effect. At a concentration of 4-HC commonly used for BM purging (60 micrograms/mL), there were 4 to 5 logs of T-cell depletion and almost complete elimination of NK- and LAK-cell activity. In contrast, 4-HC at low concentrations (eg, 3 micrograms/mL) spared the majority of lymphoid cells suggesting that low concentration 4-HC combined with MoAb purging may be a desirable alternative to higher concentration 4- HC. These data indicate that purging with antimyeloid MoAbs, but not with 4-HC, spares the function of mature graft lymphocytes. Infusion of viable lymphocytes may be important for the transfer of immune memory against microbial and neoplastic antigens and may hasten immune reconstitution. In addition, mature graft lymphocytes may also be selectively activated and expanded in conjunction with interleukin-2 administration after BM transplantation.  相似文献   
127.
Sixty-two patients with acute nonlymphoblastic leukemia in first relapse or second remission were treated with allogeneic marrow transplantation from HLA-matched siblings. In 17 patients (group 1), no attempt at reinduction of remission was made prior to transplantation. In 20 patients (group 2), attempts at inducing a second remission prior to transplantation were unsuccessful; and in 25 patients (group 3), a second remission was achieved. Five of 17 patients (29%) in group 1, 2 of 20 (10%) in group 2, and 5 of 25 (20%) in group 3 are surviving disease-free 2-6 yr after grafting. Early mortality from nonleukemic causes was equal in the 3 groups, but the risk of recurrent leukemia after transplantation was less in patients transplanted without attempts at reinduction (group 1). Among patients transplanted in relapse, those in early relapse (less than 30% blast cells in the marrow) appeared to do better than patients in florid relapse. The results obtained in group 1 are as good as or better than those achieved in patients transplanted in second or subsequent remission. Thus, for patients with acute nonlymphoblastic leukemia not transplanted in first remission, the optimal time for transplantation would appear to be as soon as possible after the first relapse.  相似文献   
128.
Durnam  DM; Anders  KR; Fisher  L; O'Quigley  J; Bryant  EM; Thomas  ED 《Blood》1989,74(6):2220-2226
A Y-chromosome-specific in situ hybridization assay was used to assess the frequency with which host bone marrow cells are retained after marrow grafting. The majority of patients (74%) showed the presence of both host and donor marrow cells when assayed 14 days after transplant. By 84 days posttransplant only 4% of the patients retained host marrow cells. Only 1 of 19 evaluable patients analyzed over 1 year posttransplant showed minimal retention of host cells. No statistical correlation was found between retention of host cells posttransplant and the development of relapse or acute or chronic graft-versus-host disease. Pretransplant conditioning regimen, HLA-matching, diagnosis, disease status at transplant, ABO-matching, and patient age also showed no correlation with the retention of host cells posttransplant.  相似文献   
129.
Graziano  RF; Ball  ED; Fanger  MW 《Blood》1983,61(6):1215-1221
Antigenic changes detected by myeloid-specific monoclonal antibodies on HL-60 cells induced to differentiate by various chemical mediators were investigated using flow cytometry. Antigen levels detected by monocyte- granulocyte-specific monoclonal antibodies AML-2-23, 61D3, and 63D3 increased dramatically after differentiation of HL-60 cells along the granulocytic pathway by the addition of dimethyl formamide (DMF), dimethylsulfoxide (DMSO), or cis-retinoic acid. The expression of these same antigens also increased in conjunction with monocytoid differentiation when HL-60 cells were treated with supernatants from leukocytes stimulated with phytohemagglutinin (PHA-LCM) or with mixed lymphocyte conditioned medium (MLC). In contrast, treatment of HL-60 cells with phorbol 12-myristate 13-acetate (PMA), which also induced differentiation along the monocyte pathway, had no effect on the expression of these monocyte-associated antigens. The expression of antigens on HL-60 cells recognized by the granulocyte-specified monoclonal antibodies PMN 6 and PMN 29 decreased after treatment of HL- 60 cells with PMA, but remained constant after treatment with DMF, DMSO, cis-retinoic acid, PHA-LCM, or MLC. These results suggest that normal myeloid differentiation may be dependent on various signals and that morphological and cell surface marker maturity may, under some conditions, be separable. The utility of the HL-60 cell line as a model of myeloid differentiation and for evaluation of inductive signals is discussed.  相似文献   
130.
Appelbaum  FR; Fisher  LD; Thomas  ED 《Blood》1988,72(1):179-184
We previously published the results of a prospective comparison of continued chemotherapy or marrow transplantation for adults with acute nonlymphocytic leukemia (ANL) who had achieved a first remission. This report updates that study now that greater than 5 years have passed since the last patient was entered. Among 86 patients eligible for comparison, 43 had no donors and were treated with continued chemotherapy, 43 had donors, but 10 declined transplantation and 33 were transplanted. Five-year disease-free survivals are 21% for the chemotherapy group, 48% for the transplant group, and 10% for the group with matched siblings who declined transplantation.  相似文献   
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