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11.
Hematologic profiles of 462 persons, mostly active-duty service members, were studied to determine whether hematologic differences between blacks and whites exist in a healthy population. Whites had significantly greater mean concentrations of leukocytes (6.73 vs 5.95 x 10(9)/L), neutrophils (3.96 vs 3.16 x 10(9)/L), and hemoglobin (153 vs 135 g/L for men, 147 vs 125 g/L for women). The mean differences were largely due to relatively symmetric shifts in the frequency distributions for these cell concentrations. No significant correlation was found between neutrophil count and morbidity from infection as measured by a standardized questionnaire. The use of separate hematologic reference values for blacks and whites should be considered. 相似文献
12.
J. Thiele T. K. Zirbes J. Lorenzen H. M. Kvasnicka S. Scholz A. Erdmann U. Flucke V. Diehl R. Fischer 《Annals of hematology》1997,75(1-2):33-39
In order to determine the dynamics of hematopoietic cell turnover, proliferative activity and incidence of apoptosis (programmed
cell death) were evaluated in bone marrow trephine biopsies. Selection of patients (20 in each group) included in addition
to a control group, idiopathic thrombocytopenia (ITP), reactive thrombocytosis (TH), secondary polycythemia-smokers' polyglobuly
(PG), primary (essential-hemorrhagic) thrombocythemia (PTH), polycythemia vera (PV), and finally acute myeloid leukemia (AML).
Apoptosis was demonstrated by the in situ end-labeling technique (ISEL) and proliferative activity by applying the monoclonal
antibody PC10 raised against proliferating cell nuclear antigen (PCNA). To assess dynamic features of hematopoiesis, an index
was calculated consisting of the ratio between PCNA-positive nuclei and the apoptotic cell fraction. This factor was termed
the hematopoietic turnover index (HTI). Morphometric analysis revealed that the HTI was significantly increased in AML and
PV. According to cell culture studies both disorders are characterized by either a prevalent proliferation of the myeloid
or erythroid cell mass. On the other hand, PG, PTH, and TH showed no relevant enhancement of this index in comparison to the
control specimen. In vitro experiment results are in keeping with the finding that PG and PTH are not associated with a significant
expansion of the erythroid lineage (CFU-E). Similar to ITP and TH, in PTH megakaryocyte proliferation (CFU-MEG) is the predominant
feature of cell turnover. Differences between PTH and TH are in line with the reduced in vitro formation of CFU-MEG in the
latter disorder. In conclusion, our in situ study on turnover rates of the bone marrow in various neoplastic and reactive
lesions extends previous experimental data on hematopoietic cell kinetics.
Received: 10 March 1997 / Accepted: 18 May 1997 相似文献
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Reducing waste of intravenous solutions. 总被引:1,自引:0,他引:1
A program to minimize the waste of i.v. drug solutions is outlined, and the results of audits to determine the effectiveness of the program are presented. The program for reducing i.v. solution waste at a 500-bed acute-care center involves measures to compound admixtures for individual shifts, recycle solutions, remove unused solutions from nursing units, use a standardized administration schedule and automatic stop orders, standardize total parenteral nutrient (TPN) solutions, use commercially prepared products when possible, verify telephone orders, and prepare labile products just before use. From January 1987 to January 1990, six 30-day audits were performed to determine the number of i.v. admixtures discarded. The audits showed the hospital's average rate of waste to be 3.27%, well below other published values. The medical and surgical intensive-care units, pediatrics wards, and general medicine units accounted for most of the waste, which was largely attributable to dosage changes and stat-type drugs ordered but never used. Poor communication between the pharmacy and the nursing units also contributed to sterile product waste. Although the audits showed that waste was already at a low level, they pointed out areas for further improvement. A computer linkup that gives physicians the formulas for i.v. solutions is being set up, the list of standardized TPN solution formulas is being expanded to include condition-specific solutions, and clinical pharmacists are establishing better communication with the nursing units. By using several methods to reduce the waste of i.v. solutions, a pharmacy department has limited the rate of waste to only 3.27%. 相似文献
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A. M. Diehl MD M. A. Chacon PhD J. J. Potter MS D Rolfes MD D. F. Cruess MD E Mezey MD 《Alcoholism, clinical and experimental research》1987,11(4):385-391
It has been suggested that pyridoxine deficiency may potentiate ethanol-induced liver injury. Our purpose was to clarify the effect of pyridoxine deficiency on ethanol-associated liver injury by comparing liver histology, serum liver enzymes, and the viability of cultured hepatocytes from pyridoxine-deficient and pyridoxine-sufficient rats that had been chronically fed ethanol-enriched diets. Our data fail to substantiate that pyridoxine-deficient animals are more susceptible to the hepatotoxic effects of ethanol than pair-fed pyridoxine-sufficient controls. Furthermore, the addition of pyridoxine to hepatocyte cultures fails to prevent in vitro cytotoxicity of added ethanol. Pyridoxine deficiency may augment ethanol-induced enhancement of hepatic urea synthesis. These data suggest that pyridoxine deficiency may contribute to the abnormal plasma amino acid profiles and nitrogen balance of chronic alcoholics, but that it does not potentiate ethanol-induced liver injury. 相似文献
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PURPOSE: Although the angle of deviation in patients with congenital esotropia has been shown to increase during the early preoperative period, few data exist regarding this change in other forms of childhood esotropia. The primary objective of this study was to investigate whether the angle of deviation increases with time in patients with acquired nonaccommodative esotropia (ANAET). METHODS: The medical records of all children whose ANAET was diagnosed at East Tennessee State University College of Medicine from August 1, 1995, through October 1, 2001, were retrospectively reviewed. All patients were assessed for any change in the amount of their strabismic angle and associated risk factors. RESULTS: Eighty-two patients with ANAET were identified, and all except 3 underwent more than one examination. Of the 79 children who underwent more than one examination, 26 (32.9%) displayed an angle increase of > or =10 prism diopters (PD) during a median follow-up period of 2.9 months. The ANAET of those patients whose angle increased by > or =10 PD was diagnosed (28.4 months of age vs 45.5 months of age, P =.003), and they underwent surgery (35.9 months of age vs 53.3 months of age, P =.003) at a significantly younger median age than those whose angle increased <10 PD. CONCLUSIONS: The angle of deviation of approximately one third of patients with ANAET in this study increased at least 10 PD in the early preoperative period. This increase occurs more often in younger patients and underscores the importance of performing serial measurements of the deviating angle before surgical intervention is undertaken. 相似文献
20.
The possibility of reducing the number of animals in sensitization studies (maximization method) is discussed on the basis of results from 20 sensitization tests. It appears that the number of test animals in sensitization studies may be reduced to ten treated animals and five control animals without prejudice to the quality of the test. 相似文献