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991.
SA Khan MRCP JE Pace MRCP ML Cox MRCP DW Gau FRCGP SAL Cox MRCGP HM Hodkinson FRCP 《International journal of clinical practice》1994,48(5):240-242
SUMMARY The incidence of climacteric symptoms was determined in 247 healthy premenopausal women in a community setting. These volunteers had been recruited to a longitudinal study of bone density. Of these subjects, 46 ceased to menstruate during the study, and in this subgroup symptoms were compared before and after cessation of menstruation. Only hot flushes increased after cessation of menstruation in the longitudinal study and showed age correlation in the cross-sectional study. Hot flushes thus emerged as a true menopausal symptom. Although evidence for this is weaker, cold sweats and suffocation seem likely to be genuinely menopausal. Breast discomfort and the four mood symptoms of irritability, excitability, depression and poor concentration improved after cessation of menstruation, and this study gives no support for their being part of the menopausal syndrome; it suggests that these symptoms are more likely to be related to menstruation than to the menopause. 相似文献
992.
Evaluation of platelet concentrates prepared from buffy coats and stored in a glucose-free crystalloid medium 总被引:3,自引:0,他引:3
F Bertolini ; P Rebulla ; D Riccardi ; M Cortellaro ; ML Ranzi ; G Sirchia 《Transfusion》1989,29(7):605-609
Comparison was made between platelet concentrates prepared from pools of buffy coats removed from standard blood donations and stored in a glucose-free, commercially available crystalloid solution (BC-PCs) and standard platelet concentrates prepared from platelet-rich plasma (PRP-PCs). Platelet yield in BC-PCs and PRP-PCs was 59 and 75 percent of donated platelets, respectively. The number of total white cells in 1 BC-PC unit, prepared from a pool of 7 buffy coats, was 21 x 10(6), i.e., 50 times lower than that of 7 units of PRP-PCs. The in vitro values of adequate platelet quality were maintained for 10 days in BC-PCs stored in 1000-mL polyolefin bags. Prolonged bleeding times were reduced or corrected in three of three thrombocytopenic leukemic patients evaluated before and after transfusion of stored BC-PCs. Pretransfusion and 1- and 24-hour posttransfusion median platelet counts in 57 leukemic recipients during 4 months of routine transfusion of BC-PCs (n = 93) were 14, 35, and 27 x 10(9) per L, while those of PRP-PCs (n = 246) were 13, 37, and 31 x 10(9) per L, respectively. No reactions to BC-PCs were reported, but a 1.3 percent rate of reaction to PRP-PC transfusions was reported. This study indicates that BC-PCs are a good alternative to PRP-PCs for platelet support of thrombocytopenic patients. 相似文献
993.
Somatically mutated forms of a major anti-p-azophenylarsonate antibody variable region with drastically reduced affinity for p-azophenylarsonate. By-products of an antigen-driven immune response? 总被引:1,自引:5,他引:1 下载免费PDF全文
T Manser B Parhami-Seren MN Margolies ML Gefter 《The Journal of experimental medicine》1987,166(5):1456-1463
The pivotal role played by antigen in the clonal selection of B cells for initial participation in an immune response is well established. Antigen selective mechanisms ensure that antigen-binding antibodies are produced during all stages of the immune response. However, antibodies that lack specificity for the immunogen might also be produced during the course of an antigen-driven immune response . It has been suggested that, through idiotype-antiidiotype network interactions within the immune system, production of antibodies that lack specificity for the immunogen but that share idiotopes with antigen-binding antibodies could result (1). In addition, data obtained by a number of investigators suggest that somatic mutation of antibody V region genes occurs at a rate of 10(-3)/basepair/cell division in B cells participating in an immune response (2, 3). One outcome of such V region structural alteration could be antibodies that lack, or have drastically reduced affinity for the immunogen . We sought to identify and characterize some of the antibody by-products of the antigen-driven immune response that are expected to be created by the mechanisms described above. 相似文献
994.
Kirby RL Dupuis DJ Macphee AH Coolen AL Smith C Best KL Newton AM Mountain AD Macleod DA Bonaparte JP 《Archives of physical medicine and rehabilitation》2004,85(5):794-804
OBJECTIVE: To evaluate the measurement properties of the Wheelchair Skills Test (WST), version 2.4. DESIGN: Cohort study. SETTING: Rehabilitation center. PARTICIPANTS: A total of 298 subjects (169 wheelchair users, 129 able-bodied subjects) ranging in age from 17 to 88 years. INTERVENTION: We videotaped subjects as they attempted the 50 skills of the WST 2.4. MAIN OUTCOME MEASURES: The test-retest, intrarater, and interrater reliabilities were determined on a subset of 20 wheelchair users. We assessed construct validity by evaluating whether the WST detected expected changes and concurrent validity by seeing how well total WST scores correlated with criterion measures. RESULTS: The mean time +/- standard deviation taken to administer the WST was 27.0+/-9.3 minutes. There were no serious adverse incidents, and the test was well tolerated. For the test-retest, intrarater and interrater reliabilities, the intraclass correlation coefficients for the total scores were.904,.959, and.968. For individual skills, the percentage concordance ranged from 73% to 100%. Regarding construct validity, there was a slightly negative Pearson correlation between total WST score and age (-.434). Gender was identified as a significant factor on multiple regression analysis (P<.001). Wheelchair users with more than 21 days of experience scored higher than those with less experience (65.0% vs 59.6%; P=.01). Participants with stroke and related disorders had a mean score (55.0%+/-13.9%) that was significantly lower than those in other diagnostic categories (P<.05). Participants using conventional wheelchairs had lower scores than those in lightweight ones (66.4% vs 75.1%; P<.001). Regarding concurrent validity, Spearman rank correlations between total WST scores and the global assessments of the wheelchair users' therapists and admission and discharge FIM instrument scores were.394,.38, and.31. CONCLUSIONS: The WST 2.4 is practical and safe, and its measurement properties are very good to excellent. Further study is needed to determine its usefulness in various clinical settings. 相似文献
995.
Parminder S Suchdev Sorrel ML Namaste Grant J Aaron Daniel J Raiten Kenneth H Brown Rafael Flores-Ayala 《Advances in nutrition (Bethesda, Md.)》2016,7(2):349-356
Anemia remains a widespread public health problem. Although iron deficiency is considered the leading cause of anemia globally, the cause of anemia varies considerably by country. To achieve global targets to reduce anemia, reliable estimates of the contribution of nutritional and non-nutritional causes of anemia are needed to guide interventions. Inflammation is known to affect many biomarkers used to assess micronutrient status and can thus lead to incorrect diagnosis of individuals and to overestimation or underestimation of the prevalence of deficiency in a population. Reliable assessment of iron status is particularly needed in settings with high infectious disease burden, given the call to screen for iron deficiency to mitigate potential adverse effects of iron supplementation. To address these information gaps, in 2012 the CDC, National Institute for Child Health and Human Development, and Global Alliance for Improved Nutrition formed a collaborative research group called Biomarkers Reflecting Inflammation and Nutrition Determinants of Anemia (BRINDA). Data from nationally and regionally representative nutrition surveys conducted in the past 10 y that included preschool children and/or women of childbearing age were pooled. Of 25 data sets considered for inclusion, 17 were included, representing ∼30,000 preschool children, 26,000 women of reproductive age, and 21,000 school-aged children from all 6 WHO geographic regions. This article provides an overview of the BRINDA project and describes key research questions and programmatic and research implications. Findings from this project will inform global guidelines on the assessment of anemia and micronutrient status and will guide the development of a research agenda for future longitudinal studies. 相似文献
996.
Primary hyperparathyroidism in a paediatric hospital 总被引:1,自引:0,他引:1
Lawson ML; Miller SF; Ellis G; Filler RM; Kooh SW 《QJM : monthly journal of the Association of Physicians》1996,89(12):921-932
We retrospectively reviewed the presentation and management of children
with primary hyperparathyroidism (PHPT) from 1973 to 1995 at a paediatric
tertiary-care centre. There were 11 patients (6 females), aged 12.3-17.7
years at presentation, with sporadic PHPT confirmed by histopathology
(single adenoma). Presentation consisted of renal colic, or non-specific
gastrointestinal, musculoskeletal or neurological symptoms. Misdiagnosis
was common until hypercalcaemia was identified, 0.5-24 months after onset
of symptoms (mean 7.7 months). All patients had hypercalcaemia and
low-normal serum phosphate. The parathyroid hormone (PTH) radioimmunoassay
used before 1986 was elevated in 1/4 patients; the intact PTH assay used
after 1986 was elevated in 7/7 patients. At presentation, six had end-organ
damage: band keratopathy, renal lesions, and/or bone disease. Preoperative
localization was accurate in 0/4 patients diagnosed before 1986, but 5/7
patients diagnosed after 1986: three by ultrasound or sestamibi scan alone,
and two by ultrasound and technetium scan. Surgical outcome was not
dependent upon the accuracy of pre-operative localization. PHPT is rare in
children but usually associated with end-organ damage, presumably due to
delayed diagnosis. It should be considered in the differential diagnosis of
unexplained non-specific complaints. The intact PTH assay greatly assists
pre-operative diagnosis. The usefulness of pre- operative localization
requires further research.
相似文献
997.
Blood collections by community blood centers, 1988 through 1992 总被引:1,自引:0,他引:1
BACKGROUND: The provision of a safe and sufficient supply of blood is critical to patient care. STUDY DESIGN AND METHODS: A survey was conducted of the blood collection activity of the 189 community blood centers operating in the United States from 1988 through 1992. Data were analyzed by source of the donation (allogeneic or autologous), by center's collection volume, and by geographic region. Total collection figures were compared to historical blood collection activity since 1970. RESULTS: A total of 12.31 million units of blood were collected in 1992, an increase of 2.6 percent over the total number of units collected in 1988. For the 5-year period (1988-1992), total collections increased at a compound annual growth rate of 0.6 percent. The collection of allogeneic blood units declined by 0.2 percent annually, while that of autologous units increased by 23.2 percent annually. Autologous blood units accounted for 5.7 percent of total collections in 1992. Nationally, 48 units were collected per 1000 people in 1992, although substantial geographic variation (range, 38–64 units/1000) was observed across nine US census regions. CONCLUSION: The data from this study provide evidence that the total supply of blood grew more slowly from 1988 through 1992 than in the years before 1988. 相似文献
998.
A one-step Du test, developed for use in automated microplate systems, uses anti-D with 0.6 percent dextran to potentiate the reaction. Because the washing and reagent-adding steps of the antiglobulin test are not required, the Du test can be performed in the same microplate as the ABO/Rh test. A set of reactions prepared with this technique was visually interpreted and also classified by an automated microplate ABO/Rh system. Visual interpretation of reactions resulted in a sensitivity and specificity close to those of the antiglobulin test, although the sensitivity of the test was reagent-dependent. When the automated microplate blood grouping system was used, the test was not as sensitive or as specific as the antiglobulin test, although it may be sufficient for many applications. 相似文献
999.
Winkler U; Gottstein C; Schon G; Kapp U; Wolf J; Hansmann ML; Bohlen H; Thorpe P; Diehl V; Engert A 《Blood》1994,83(2):466-475
To evaluate the effects of deglycosylated ricin A-chain (dgA) immunotoxins against disseminated Hodgkin's lymphoma, we used RFT5.dgA (CD25) and IRac.dgA (70 kD) to treat L540Cy Hodgkin cells in severely immunodeficient SCID mice. In this model, more than 90% of the animals developed multiple lymphomas in various organs such as the lymph nodes, liver, bone marrow, and extranodal sites that killed untreated animals after a mean survival time (MST) of 36.3 days. A single intraperitoneal injection of 8 micrograms of either immunotoxin rendered 95% (RFT5.dgA) and 93% (IRac.dgA), respectively, of mice tumor-free when applied 1 day after tumor challenge. The MST of the RFT5.dgA-treated group was extended by more than 80 days (P < .00001). SCID mice treated 12 days after tumor challenge had lower remission rates (46%), suggesting that the antitumor effect of the immunotoxins depends on the number of tumor cells present. We conclude that ricin A-chain immunotoxins have potent antitumor effects against disseminated Hodgkin's tumors in SCID mice and that this model is ideally suited for the evaluation of different immunotoxin treatment modalities. 相似文献
1000.