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21.
G. Bert Donatella Lajolo Di Cossano Paola Pecco 《Clinical and experimental immunology》1969,5(6):669-672
The electrophoretic mobility of peripheral blood lymphocytes from human subjects with positive Mantoux tests was measured before and after treatment with purified protein derivative. Lymphocytes from subjects with negative Mantoux reactions were used as controls. A large number of the first group lymphocytes showed a reduction of electrophoretic mobility and hence of the surface electrical charge. The mobility of the control cells submitted to the same treatment was unchanged. The possible presence of cytophilic antibodies or of cellular specific receptors on the lymphocyte surface is discussed. 相似文献
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John M. Ruiz Bert N. Uchino Timothy W. Smith 《International journal of psychophysiology》2006,60(3):274-283
Recent models hypothesize that hostility confers increased risk of CHD through weaker parasympathetic dampening of cardiovascular reactivity (CVR). We tested this possibility using the forehead cold pressor task, a common maneuver which elicits the “dive reflex” characterized by a reflexive decrease in HR presumably through cardiac-parasympathetic stimulation. Participants were initially chosen from the outer quartiles of a sample of 670 undergraduates screened using the hostility subscale of the Aggression Questionnaire ([Buss, A.H., Perry, M., 1992. The Aggression Questionnaire. Journal of Personality and Social Psychology, 63, 452-459.]). The final sample of 80 participants was evenly divided between men and women and high and low hostility. Following a 10-min baseline, participants underwent a 3-min forehead cold pressor task. The task evoked a significant HR deceleration that was mediated by PNS activation, as assessed by respiratory sinus arrhythmia (RSA). Replicating prior research, men displayed greater decrease in HR. More important, low hostiles maintained larger HR deceleration over time compared to high hostiles although the autonomic basis for this effect was unclear. The findings broaden understanding of hostility and sex-related cardiovascular functioning and support the task as a method for evoking PNS-cardiac stimulation. 相似文献
25.
Juergen Thiele Bert Hoeppner Rudolf Zankovich Robert Fischer 《Virchows Archiv : an international journal of pathology》1989,415(3):191-202
Summary Histomorphometry was performed on representative trephine biopsies of the bone marrow on admission of 50 patients (21 male, 29 female-age 67 years) with so-called primary osteomyelofibrosis/-sclerosis (OMF) not preceded by any other subtype of chronic myeloproliferative disorders. This study was firstly aimed at testing correlations between histological features (amount of haematopoiesis, cytological aspects of mega-karyocytes, density of reticulin and collagen fibres and degree of osteosclerosis) and laboratory data, as well as spleen size and duration of relevant prediagnostic symptoms. Secondly, we concentrated on a discrimination of OMF patients into two sub-groups according to bone marrow morphology and clinical variables. Statistical evaluation of histomorphometric variables and haematological findings disclosed that there was a progressive fibro-osteosclerotic process in the evolution of disease features. Increase in medullary fibrosis was significantly paralleled by an abnormal or pleomorphic megakaryopoiesis in the bone marrow: there was an increase in irregularity of perimeters for megakaryocytes and naked nuclei combined with smaller sizes of these elements including the nuclei. Additionally, there was a greater number of pycnotic bare nuclei. A number of morphometric features (density of fibres, degree of osteosclerosis, amount of haematopoiesis) were associated with corresponding clinical data (spleen size, length of preclinical history). By consideration of a set of basic histomorphometric variables our co-hort of 50 patients could be divided into an early hyperplastic subtype with no or minimal medullary reticulin and another group with conspicuous fibrotic and osteosclerotic alterations of the bone marrow. It was noticeable that we found no significant correlation between amount of haematopoiesis or marrow cellularity with splenomegaly. This result suggests that splenic haematopoiesis (myeloid metaplasia) may represent an autonomous or neoplastic process and not only compensation for a failing fibro-osteosclerotic bone marrow.Supported by a grant from the Deutsche Forschungsgemeinschaft (DFG-Th 390/1-1) 相似文献
26.
Breast cancer risk associated with ovulation-stimulating drugs 总被引:4,自引:0,他引:4
Brinton LA Scoccia B Moghissi KS Westhoff CL Althuis MD Mabie JE Lamb EJ 《Human reproduction (Oxford, England)》2004,19(9):2005-2013
BACKGROUND: Despite the recognized role of hormones in the aetiology of breast cancer, there has been little evaluation of hormonal preparations used to treat infertility. METHODS: A retrospective cohort study of 12,193 women evaluated for infertility between 1965 and 1988 at five clinical sites identified 292 in situ and invasive breast cancers in follow-up through 1999. Standardized incidence ratios (SIRs) compared breast cancer risks with those of the general population. Analyses within the cohort estimated rate ratios (RRs) associated with medications after adjustment for other breast cancer predictors. RESULTS: Infertile patients had a significantly higher breast cancer risk than the general population [SIR = 1.29, 95% confidence interval (CI) 1.1-1.4]. Analyses within the cohort showed adjusted RRs of 1.02 for clomiphene citrate and 1.07 for gonadotrophins, and no substantial relationships to dosage or cycles of use. Slight and non-significant elevations in risk were seen for both drugs after > or = 20 years of follow-up (RRs = 1.39 for clomiphene and 1.54 for gonadotrophins). However, the risk associated with clomiphene for invasive breast cancers was statistically significant (RR = 1.60, 95% CI 1.0-2.5). CONCLUSIONS: Although there was no overall increase in breast cancer risk associated with use of ovulation-stimulating drugs, long-term effects should continue to be monitored. 相似文献
27.
The probability of synaptic transmitter release determines the spread of excitation and the possible range of computations at unitary connections. To investigate whether synaptic properties between neocortical pyramidal neurons change during the assembly period of cortical circuits, whole-cell voltage recordings were made simultaneously from two layer 5A (L5A) pyramidal neurons within the cortical columns of rat barrel cortex. We found that synaptic transmission between L5A pyramidal neurons is very reliable between 2 and 3 weeks of postnatal development with a mean unitary EPSP amplitude of ∼1.2 mV, but becomes less efficient and fails more frequently in the more mature cortex of ∼4 weeks of age with a mean unitary EPSP amplitude of 0.65 mV. Coefficient of variation and failure rate increase as the unitary EPSP amplitude decreases during development. The paired-pulse ratio (PPR) of synaptic efficacy at 10 Hz changes from 0.7 to 1.04. Despite the overall increase in PPR, short-term plasticity displays a large variability at 4 weeks, ranging from strong depression to strong facilitation (PPR, range 0.6–2.1), suggesting the potential for use-dependent modifications at this intracortical synapse. In conclusion, the transmitter release probability at the L5A–L5A connection is developmentally regulated in such a way that in juvenile animals excitation by single action potentials is efficiently transmitted, whereas in the more mature cortex synapses might be endowed with a diversity of filtering characteristics. 相似文献
28.
Tony Wawina-Bokalanga Bert Vanmechelen Valentine Lhermitte Joan Martí-Carreras Valentijn Vergote Fara Raymond Koundouno Joseph Akoi-Bor Ruth Thom Tom Tipton Kimberley Steeds Kita Balla Moussa Ablam Amento Lies Laenen Sophie Duraffour Martin Gabriel Paula Ruibal Yper Hall Mandy Kader-Kond Stephan Günther Guy Baele Cesar Muoz-Fontela Johan Van Weyenbergh Miles W. Carroll Piet Maes 《Emerging infectious diseases》2021,27(1):76
We investigated the genetic profiles of killer cell immunoglobulin-like receptors (KIRs) in Ebola virus–infected patients. We studied the relationship between KIR–human leukocyte antigen (HLA) combinations and the clinical outcomes of patients with Ebola virus disease (EVD). We genotyped KIRs and HLA class I alleles using DNA from uninfected controls, EVD survivors, and persons who died of EVD. The activating 2DS4–003 and inhibitory 2DL5 genes were significantly more common among persons who died of EVD; 2DL2 was more common among survivors. We used logistic regression analysis and Bayesian modeling to identify 2DL2, 2DL5, 2DS4–003, HLA-B-Bw4-Thr, and HLA-B-Bw4-Ile as probably having a significant relationship with disease outcome. Our findings highlight the importance of innate immune response against Ebola virus and show the association between KIRs and the clinical outcome of EVD. 相似文献
29.
Joseph S. Munn Sharon E. Culliton Dianne M. Bryant Steven J. MacDonald Bert M. Chesworth 《The Journal of arthroplasty》2021,36(6):1942-1946
BackgroundApproximately 20% of patients are dissatisfied with their total knee arthroplasty (TKA) at 1-year post-surgery. Met expectations have been found by some to significantly predict satisfaction. The role of met expectations in determining patient satisfaction has not been exhaustively explored. The primary aim of this study is to evaluate if met expectations moderate the relationship between pain and function variables and satisfaction.MethodsPatients who underwent primary TKA for osteoarthritis were included in the study (n = 304). Patient-reported outcomes at pre-surgery and 1-year post-surgery were collected. The Knee Society Score (KSS) satisfaction subscale was used as the dependent variable. Candidate independent variables included the following: demographics, KSS, Knee injury and Osteoarthritis Outcome Score (KOOS), 12-Item Short Form Health Survey (SF-12), Hospital Anxiety and Depression Scale, Pain Catastrophizing Scale, Self-Administered Comorbidity Questionnaire, and University of California Los Angeles activity score. Separate linear regression models were created to test interactions for KSS met expectations with pain and KSS met expectations with function.ResultsSignificant predictors of satisfaction were KSS symptoms (pain), KOOS activities of daily living (function), KSS met expectations, KOOS pre-surgery activities of daily living, body mass index, and SF-12 general health. A significant interaction between met expectations and pain was found (P = .043) and the met expectations and function interaction approached significance (P = .086). For both interactions, as met expectations increased, pain and function predicted satisfaction less strongly.ConclusionMet expectations were found to moderate the relationship between pain and satisfaction. There may be more value in improving pain for patients with low met expectations.Level of evidenceLevel IV. 相似文献
30.
Bert van Rietbergen Emmanuel Biver Thierry Chevalley Keita Ito Roland Chapurlat Serge Ferrari 《Journal of bone and mineral research》2021,36(7):1351-1363
During aging, changes in endosteal and periosteal boundaries of cortical bone occur that differ between men and women. We here develop a new procedure that uses high-resolution peripheral quantitative CT (HR-pQCT) imaging and 3D registration to identify such changes within the timescale of longitudinal studies. A first goal was to test the sensitivity of the approach. A second goal was to assess differences in periosteal/endosteal expansion over time between men and women. Rigid 3D registration was used to transform baseline and all follow-up (FU) images to a common reference configuration for which the region consisting of complete slices (largest common height) was determined. Periosteal and endosteal contours were transformed to the reference position to determine the net periosteal and endosteal expansion distances. To test the sensitivity, images from a short-term reproducibility study were used (15 female, aged 21 to 47 years, scanned three times). To test differences between men and women, images from a subset of the Geneva Retirees Cohort were used (248 female, 61 male, average age 65 years, 3.5 and 7 years FU). The sensitivity study indicated a least significant change for detecting periosteal/endosteal expansion of 41/31 microns for the radius and 17/26 microns for the tibia. Results of the cohort study showed significant net endosteal retraction only in females at the radius and tibia after 3.5 years (38.0 and 38.4 microns, respectively) that further increased at 7 years FU (70.4 and 70.8 microns, respectively). No significant net periosteal changes were found for males or females at 7 years. The results demonstrate that it is possible to measure changes in endosteal contours in longitudinal studies within several years. For the investigated cohort, significant endosteal retraction was found in females but not in males. Whether these changes in cortical geometry are related to fracture risk remains to be investigated in larger cohorts © 2021 The Authors. Journal of Bone and Mineral Research published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research (ASBMR). 相似文献