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731.
732.
BACKGROUND: The clinical utility of polymorphonuclear neutrophil (PMN) transfusion therapy has been compromised, in part, by the inability to obtain sufficient quantities of functional neutrophils from donors. To define the optimal conditions for mobilization of PMNs in granulocyte donors, the effects of granulocyte-colony-stimulating factor (G-CSF) and dexamethasone, separately and in combination, on PMN counts in normal volunteers were compared. STUDY DESIGN AND METHODS: Five normal subjects were randomly assigned to each of the following single-dose regimens in 5 consecutive weeks: 1) G-CSF, 300 micrograms given subcutaneously; 2) G-CSF, 600 micrograms subcutaneously: 3) dexamethasone, 8 mg given orally; 4) G-CSF, 300 micrograms subcutaneously, plus dexamethasone, 8 mg orally; and 5) G-CSF, 600 micrograms subcutaneously, plus dexamethasone 8 mg orally. Venous blood was collected at 0, 6, 12, and 24 hours after drug administration for the determination of absolute neutrophil counts (ANCs). RESULTS: Maximal ANC was achieved at 12 hours after each regimen, except dexamethasone alone (maximum, 24 hours). Dexamethasone significantly increased the maximal ANC induced by either dose of G-CSF alone (p < 0.05). The greatest mobilization of PMNs occurred after the administration of G-CSF (600 micrograms) and dexamethasone (8 mg); the ANC increased from a mean baseline value of 3,594 per microL to 43,017 per microL at 12 hours. All of the drug regimens were well tolerated. CONCLUSION: Dexamethasone significantly increases the level of neutrophilia induced in normal subjects by G-CSF. The combination of dexamethasone and G-CSF (at the dosages used in this study) is a convenient, well-tolerated regimen for the mobilization of PMNs in the peripheral blood of granulocyte donors. Moreover, the optimal quantitative yield of PMNs is likely to be achieved by leukapheresis 12 hours after drug administration.  相似文献   
733.
Community donor plateletpheresis programs must have adequate numbers of HLA-typed donors to support the transfusion needs of alloimmunized patients, and donor pool size calculations should reflect the fact that each patient needs more than one donor to provide his or her support. The average number of donors needed to provide a patient's support was estimated as a function of donor usage and commitment. A model was developed for determining an appropriate size of the donor pool for a community donor plateletpheresis program that would incorporate the average number of donors needed per patient, the level of HLA compatibility to be maintained between patient and donor, and the frequencies of patient and donor HLA phenotypes. A database of 4338 plateletpheresis transfusions given to 591 patients from a pool of up to 870 community donors over a 3-year period was analyzed retrospectively to validate the estimates of the average number of donors needed to support a patient, which ranged from 4 to 33 donors. This database was also used to illustrate the application of the pool size determination model. Model results suggest that plateletpheresis donor pools of 1000 to 3000 donors are capable of meeting the transfusion needs of most patients at an HLA-match grade of B2 or better.  相似文献   
734.
SUMMARY In this study we investigated the possible relationship of laryngeal cancer and subclinical lead intoxication, using the depression of aminolevulinic acid dehydratase (ALAD) activity in blood as indicator. Twenty-six patients with laryngeal cancer and 53 normal controls met the criteria to enter the study. Blood ALAD activity values in the patients with laryngeal cancer ranged from 27.1 to 75.3 U/l with a mean of 50.79 U/l. The respective values in the control group ranged from 36.2 to 98 U/l with a mean of 59.76 U/l. There was a statistically significant difference between the two means (0.001 <p<0.01), whereas blood lead concentrations in all patients were within normal limits. These findings support the hypothesis that low level lead intoxication (subclinical blood lead levels), from cars, industries and products, may contribute to the risk of laryngeal cancer. Further investigation is needed to clarify the exact relationship between lead and cancer of the larynx.  相似文献   
735.
BACKGROUND: The collection of adequate numbers of neutrophils (polymorphonuclear leukocytes, PMNs) from normal donors has long hampered the development of neutrophil transfusion therapy. The stimulation of donors with granulocyte-colony-stimulating factor (G- CSF) plus dexamethasone is a promising way of improving PMN collections. STUDY DESIGN AND METHODS: Sixteen normal subjects received G-CSF (600 micrograms subcutaneously) and dexamethasone (8 mg by mouth) 12 hours before leukapheresis. Measurements included PMN morphology, immunophenotype analysis, chemiluminescence, bactericidal activity, in vivo kinetics, and adverse effects. RESULTS: A mean of 77.4 +/− 6.4 × 10(9) PMNs was collected with each leukapheresis; 14 percent were bands. PMNs had increased surface expression of CD11b, CD18, CD14, CD32, and CD64. Bactericidal capacity against Staphylococcus aureus was normal. Inducible respiratory burst was maintained, although the responses to some agonists were diminished. Returned leukapheresis cells labeled with 3H-diisopropylfluorophosphate had a modestly decreased percentage of recovery and circulated with a prolonged half- life. Migration of these cells to skin chambers was approximately equal to that of the subjects' own blood PMNs. Adverse effects included transient bone pain, headache, hunger, and insomnia. CONCLUSIONS: Precollection treatment of leukapheresis donors with G-CSF plus dexamethasone is an effective way to enhance the collection of PMNs with normal or near-normal functional properties for PMN transfusion therapy.  相似文献   
736.
737.
中药材X-射线衍射图谱研究   总被引:66,自引:0,他引:66  
为探讨中药材道地性的客观规律,以期建立相应的评估指标系统,本文选择常用中药材茜草类、贝母类、山药类三组样品,应用X-射线粉末衍射法进行图谱分析,获得了可用于标识中药材的衍射图形几何拓扑规律与图谱特征标记峰,由此观察到:不同产地茜草样品的相似性及其与欧茜草的差别;同属不同种贝母样品的相似性与差异;不同产地山药样品的相似性及与伪品的区别。本文结果预示着这一方法在揭示中药材道地性客观规律方面的广阔应用前景。  相似文献   
738.
739.

Objective

To characterize patterns in whole-person health of public health nurses (PHNs).

Design and Sample

Survey of a convenience sample of PHNs (n = 132) in 2022. PHNs self-identified as female (96.2%), white (86.4%), between the ages 25–44 (54.5%) and 45–64 (40.2%), had bachelor's degrees (65.9%) and incomes of $50-75,000 (30.3%) and $75-100,000/year (29.5%).

Measurements

Simplified Omaha System Terms (SOST) within the MyStrengths+MyHealth assessment of whole-person health (strengths, challenges, and needs) across Environmental, Psychosocial, Physiological, and Health-related Behaviors domains.

Results

PHNs had more strengths than challenges; and more challenges than needs. Four patterns were discovered: (1) inverse relationship between strengths and challenges/needs; (2) Many strengths; (3) High needs in Income; (4) Fewest strengths in Sleeping, Emotions, Nutrition, and Exercise. PHNs with Income as a strength (n = 79) had more strengths (t = 5.570, p < .001); fewer challenges (t = -5.270, p < .001) and needs (t = -3.659, p < .001) compared to others (n = 53).

Conclusions

PHNs had many strengths compared to previous research with other samples, despite concerning patterns of challenges and needs. Most PHN whole-person health patterns aligned with previous literature. Further research is needed to validate and extend these findings toward improving PHN health.  相似文献   
740.
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