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Furtado PS Costa MP Ribeiro do Prado Valladares F Oliveira da Silva L Lordêlo M Lyra I Barroso U 《International journal of hematology》2012,95(6):648-651
To evaluate priapism rates in individuals <18 years of age with sickle cell disease (SCD) at a referral center. An evaluation was made of 599 consecutive male patients with SCD, separated according to type of hemoglobinopathy (HbSS, HbSC and HbS-β-thalassemia). Age at first episode and number of episodes were recorded. Cases of sickle cell trait were excluded. Mean age was similar in all groups. Overall, priapism occurred in 3.6 % of patients (5.6 % of those with HbSS and 1.1 % of those with HbSC; P = 0.01). In HbSS patients, the prevalence rate of priapism was from 3.5 (CI 95 % 0.94-13.4) when compared with patients with HbSC. No patient with β-thalassemia had priapism. Mean follow-up was 39.7 months (range 1-202 months). Since 91 % of patients with priapism had HbSS, this group was evaluated separately, revealing a rate of priapism of 1.6 % in patients <10 years and 8.3 % in those ≥ 10 years of age (P = 0.002). Regarding priapism in HbSS patients ≥ 10 years (8.3 %) when compared with patients <10 years (1.6 %), the prevalence rate was from 3.3 (CI 95 % 1.1-9.5). Duration of follow-up was not correlated with priapism (P = 0.774). Forty-seven patients were lost to follow-up. Telephone contact was successful with 14/22 patients with priapism, 50 % of whom had required hospital treatment. Most episodes (86 %) occurred at night, always during sleep. Medical interventions were required in 13 cases as follows: intravenous hydration (n = 4), corpora cavernosa puncture and drainage (n = 7) and corpus cavernosum-corpus spongiosum shunts (n = 2). The prevalence of priapism in children <18 years of age with SCD was 3.6 %, lower than previously reported. Prevalence was higher in HbSS patients, increasing in patients >10 years of age. Most episodes occurred at night and half of the patients required some form of urological procedure. 相似文献
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Jo JA Blasi A Valladares EM Juarez R Baydur A Khoo MC 《Annals of biomedical engineering》2007,35(8):1425-1443
Using the Volterra–Wiener approach, we employed a minimal model to quantitatively characterize the linear and nonlinear effects
of respiration (RCC) and arterial blood pressure (ABR) on heart rate variability (HRV) in normal controls and subjects with
moderate-to-severe obstructive sleep apnea syndrome (OSAS). Respiration, R–R interval (RRI), blood pressure (BP) and other
polysomnographic variables were recorded in eight normal controls and nine OSAS subjects in wakefulness, Stage 2 and rapid
eye-movement sleep. To increase respiratory and cardiovascular variability, a preprogrammed ventilator delivered randomly
timed inspiratory pressures that were superimposed on a baseline continuous positive airway pressure. Except for lower resting
RRI in OSAS subjects, summary statistical measures of RRI and BP and their variabilities were similar in controls and OSAS.
In contrast, RCC and ABR gains were significantly lower in OSAS. Nonlinear ABR gain and the interaction between respiration
and blood pressure in modulating RRI were substantially reduced in OSAS. ABR gain increased during sleep in controls but remained
unchanged in OSAS. These findings suggest that normotensive OSAS subjects have impaired daytime parasympathetic and sympathetic
function. Nonlinear minimal modeling of HRV provides a useful, insightful, and comprehensive approach for the detection and
assessment of abnormal autonomic function in OSAS.
Supported by NIH Grants HL-58725, EB-001978, and M01 RR-43 相似文献
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Acute stimulation of aromatization in Leydig cells by human chorionic gonadotropin in vitro. 下载免费PDF全文
L E Valladares A H Payne 《Proceedings of the National Academy of Sciences of the United States of America》1979,76(9):4460-4463
Aromatization of testosterone in Leydig cells purified from mature rat testes was assessed. Leydig cells incubated for 4 hr with increasing concentrations of [3H]testosterone. At saturating concentrations of testosterone, human chorionic gonadotropin (hCG) acutely stimulated aromatization. This stimulation was first observed at 1 hr, an 8-fold increase being found during a 4-hr incubation. The maximal amount of estradiol produced at saturating concentrations of testosterone and hCG was 1.8 ng per 10(6) cells. These results demonstrate that purified Leydig cells have a high capacity for aromatization and that hCG can acutely stimulate aromatization independently of stimulating testosterone synthesis in vitro. 相似文献
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Magdalena Kraft Macarena Pia Knop Jean-Marie Renaudin Kathrin Scherer Hofmeier Claudia Pföhler Maria Beatrice Bilò Roland Lang Regina Treudler Nicola Wagner Thomas Spindler Jonathan O'B Hourihane Ioana Maris Alice Koehli Andrea Bauer Lars Lange Sabine Müller Nikolaos G. Papadopoulos Bettina Wedi Anne Moeser Luis F. Ensina Montserrat Fernandez-Rivas Ewa Cichocka-Jarosz George Christoff Blanca E. Garcia Iwona Poziomkowska-Gęsicka Victoria Cardona Tihomir B. Mustakov Uta Rabe Vera Mahler Linus Grabenhenrich Sabine Dölle-Bierke Margitta Worm The Network for Online Registration of Anaphylaxis 《Allergy》2020,75(4):901-910
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Kimberley A. Pitman Raphael Ricci Robert Gasperini Shannon Beasley Macarena Pavez Jac Charlesworth Lisa Foa Kaylene M. Young 《Glia》2020,68(2):376-392
Throughout life, oligodendrocyte progenitor cells (OPCs) proliferate and differentiate into myelinating oligodendrocytes. OPCs express cell surface receptors and channels that allow them to detect and respond to neuronal activity, including voltage-gated calcium channel (VGCC)s. The major L-type VGCC expressed by developmental OPCs, CaV1.2, regulates their differentiation. However, it is unclear whether CaV1.2 similarly influences OPC behavior in the healthy adult central nervous system (CNS). To examine the role of CaV1.2 in adulthood, we conditionally deleted this channel from OPCs by administering tamoxifen to P60 Cacna1c fl/fl (control) and Pdgfrα-CreER:: Cacna1c fl/fl (CaV1.2-deleted) mice. Whole cell patch clamp analysis revealed that CaV1.2 deletion reduced L-type voltage-gated calcium entry into adult OPCs by ~60%, confirming that it remains the major L-type VGCC expressed by OPCs in adulthood. The conditional deletion of CaV1.2 from adult OPCs significantly increased their proliferation but did not affect the number of new oligodendrocytes produced or influence the length or number of internodes they elaborated. Unexpectedly, CaV1.2 deletion resulted in the dramatic loss of OPCs from the corpus callosum, such that 7 days after tamoxifen administration CaV1.2-deleted mice had an OPC density ~42% that of control mice. OPC density recovered within 2 weeks of CaV1.2 deletion, as the lost OPCs were replaced by surviving CaV1.2-deleted OPCs. As OPC density was not affected in the motor cortex or spinal cord, we conclude that calcium entry through CaV1.2 is a critical survival signal for a subpopulation of callosal OPCs but not for all OPCs in the mature CNS. 相似文献
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Villagrán-García Macarena Muñiz-Castrillo Sergio Ciano-Petersen Nicolás Lundahl Vogrig Alberto Farina Antonio Villard Marine Psimaras Dimitri Alentorn Agusti Gonçalves David Fabien Nicole Rogemond Véronique Joubert Bastien Honnorat Jérôme 《Journal of neurology》2023,270(1):283-299
Journal of Neurology - The link between paraneoplastic neurological syndromes (PNS) and renal cell and bladder cancer (RCC/BC) is rare and uncertain. Our aim was to clinically evaluate, in light of... 相似文献
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