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91.
Connectivity as an alternative to boundary integral equations: Construction of bases 总被引:1,自引:1,他引:1 下载免费PDF全文
Herrera I Sabina FJ 《Proceedings of the National Academy of Sciences of the United States of America》1978,75(5):2059-2063
In previous papers Herrera developed a theory of connectivity that is applicable to the problem of connecting solutions defined in different regions, which occurs when solving partial differential equations and many problems of mechanics. In this paper we explain how complete connectivity conditions can be used to replace boundary integral equations in many situations. We show that completeness is satisfied not only in steady-state problems such as potential, reduced wave equation and static and quasi-static elasticity, but also in time-dependent problems such as heat and wave equations and dynamical elasticity. A method to obtain bases of connectivity conditions, which are independent of the regions considered, is also presented. 相似文献
92.
Guillermo A. Herrera MD 《Digestive diseases and sciences》1985,30(7):698-698
93.
94.
Ricardo A. Chvez Montes Anna Haber Jeremy Pardo Robyn F. Powell Upendra K. Divisetty Anderson T. Silva Tania Hernndez-Hernndez Vanildo Silveira Haibao Tang Eric Lyons Luis Rafael Herrera Estrella Robert VanBuren Melvin J. Oliver 《Proceedings of the National Academy of Sciences of the United States of America》2022,119(5)
95.
Enrique Herrera‐Acosta Gustavo G. Garriga‐Martina Jorge A. Surez‐Prez Eliseo A. Martínez‐García Enrique Herrera‐Ceballos 《Dermatologic therapy》2020,33(3)
There are no studies which directly compare efficacy in Psoriasis Area and Severity Index (PASI) response of secukinumab and ixekizumab. The main aim of this study was to compare the efficacy and safety of both drugs used to treat moderate‐to‐severe psoriasis patients over 52 weeks. Secondary objectives were to identify which factors related to prior biologic treatment influenced their efficacy and analyze data obtained at 12 weeks. A retrospective observational study was carried out, in which a group of the first 59 patients treated with secukinumab after its commercialization, was compared with another group of the first 29 patients treated with ixekizumab. The PASI 75, 90, and 100 response obtained at 52 weeks was 64.4%, 49.2%, and 41.4% for secukinumab and 75.9%, 62.1%, and 41.4% for ixekizumab, respectively, with no statistically significant differences. Regarding previous biological treatment, both treatments showed a decrease in efficacy as the number of prior biologics increases. No differences were found between secukinumab and ixekizumab in bio‐naïve or bio‐experienced patients, with the exception of a higher PASI 75 response at week 52 for ixekizumab in those patients with two or more previous biologics (P = .039) Secukinumab and ixekizumab have demonstrated high efficacy and safety, with no statistically significant differences. 相似文献
96.
C F Sanchez-Ferrer J Marin J Benitez N Herrera I Rico M Salaices 《Brain research》1987,411(2):304-309
Pentobarbital (PB) induced concentration-dependent vasodilation in cylindrical segments of cat cerebral and femoral arteries precontracted with 75 mM K+ or 10(-5) M serotonin (5-HT). PB (10(-4) or 10(-3) M, 10 min preincubations) caused concentration-dependent inhibition of the contraction produced by both agents. The exposure of the vessels to a Ca2+-free medium annulled the response elicited by K+ in both kinds of arteries. In this medium, the contraction induced by 5-HT in cerebral arteries was abolished, whereas in femoral ones it was significantly reduced. This residual response was abolished by PB. The intracellular 45Ca2+ uptake (La3+ method) elicited by K+ in both kinds of arteries and by 5-HT in cerebral ones was reduced in a concentration-dependent manner by PB (10(-4)-10(-3) M). The spontaneous 45Ca2+ efflux from these arteries and that induced by La3+ (10 mM) were unaffected by PB (10(-3) M). These results indicate that the vasodepressor effects induced by PB are essentially due to an interference of the barbiturate with the Ca2+ entry into the vascular smooth muscle cell in both kinds of arteries and with the intracellular Ca2+ movements in femoral ones. It does not seem to exist a clear selectivity of PB for brain or peripheral arteries for antagonizing the responses caused by K+ or 5-HT. 相似文献
97.
Triarylphosphines substituted with carboxylic and trifluoromethlyl groups have been prepared by the hydrolysis of trifluoromethyl groups using fuming sulfuric acid and boric acid. The reaction has been studied in a set of homoleptic and heteroleptic trifluoromethylated triarylphosphines and offers a new synthetic procedure for the preparation of carboxylic phosphines with a relatively simple methodology. The degree of carboxylation is modulated by the reaction conditions and is sensitive to the substitution pattern of the starting trifluoromethylated phosphines. A pH-dependent procedure based on the amphiphilic character of these phosphines was developed for their separation and purification. The electronic properties of the synthesized carboxylic-trifluoromethylated phosphines have been analyzed by 31P NMR of the corresponding selenide derivatives. Finally, the structures of two palladium complexes, containing the para and meta carboxylic-trifluoromethylated phosphines are also described, showing different dimeric structures.Preparation of carboxylic triarylphosphines by hydrolysis of the trifluoromethyl group in acid media. 相似文献
98.
Acupuncture in patients with acute low back pain: A multicentre randomised controlled clinical trial
J Vas JM Aranda M Modesto N Benítez-Parejo A Herrera DM Martínez-Barquín I Aguilar M Sánchez-Araujo F Rivas-Ruiz 《Pain》2012,153(9):1883-1889
Reviews of the efficacy of acupuncture as a treatment for acute low back pain have concluded that there is insufficient evidence for its efficacy and that more research is needed to evaluate it. A multicentre randomized controlled trial was conducted at 4 primary-care centres in Spain to evaluate the effects of acupuncture in patients with acute nonspecific low back pain in the context of primary care. A total of 275 patients with nonspecific acute low back pain (diagnosed by their general practitioner) were recruited and assigned randomly to 4 different groups: conventional treatment either alone or complemented by 5 sessions over a 2-week period of true acupuncture, sham acupuncture, or placebo acupuncture per patient. Patients were treated from February 2006 to January 2008. The primary outcome was the reduction in Roland Morris Disability Questionnaire scores of 35% or more after 2weeks' treatment. The patients in the 3 types of acupuncture groups were blinded to the treatments, but those who received conventional treatment alone were not. In the analysis adjusted for the total sample (true acupuncture relative risk 5.04, 95% confidence interval 2.24-11.32; sham acupuncture relative risk 5.02, 95% confidence interval 2.26-11.16; placebo acupuncture relative risk 2.57 95% confidence interval 1.21-5.46), as well as for the subsample of occupationally active patients, all 3 modalities of acupuncture were better than conventional treatment alone, but there was no difference among the 3 acupuncture modalities, which implies that true acupuncture is not better than sham or placebo acupuncture. 相似文献
99.
Valencia-Flores M Orea A Herrera M Santiago V Rebollar V Castaño VA Oseguera J Pedroza J Sumano J Resendiz M García-Ramos G 《Obesity surgery》2004,14(6):755-762
Background: We evaluated the impact of surgically-induced weight loss on Obstructive Sleep Apnea/Hypopnea Syndrome (OSAHS),
electrocardiographic changes, pulmonary arterial pressure and daytime sleepiness in morbidly obese patients. Methods: 16 women
and 13 men (n=29) underwent bariatric surgery in a 3-year period. The following tests were performed before and 1 year after
surgery: nocturnal polysomnography, daytime Multiple Sleep Latency Test (MSLT), and echocardiogram. Results: Mean age was
37.9±11 years (range 20-56). Preoperative body mass index was 56.5±12.3 kg/m2 and it was 39.2±8.5 kg/m2 at 13.7±6.6 months follow-up. Performed surgical procedures included: vertical banded gastroplasty in 6, Roux-en-Y gastric
bypass in 12, and Distal Roux-en-Y gastric bypass in 11. Weight loss induced by surgery eliminated OSAHS in 46% of obese patients
with an important improvement in oxygen saturation. Neck, thorax, waist and hip circumferences decreased significantly after
surgical intervention but only neck circumference correlated significantly with the apnea/hypopnea index (Spearman rho=0.63, P <0.0001). Electrocardiographic abnormalities were present in 9 patients (31%) before surgery (sinus arrhythmia, ventricular
arrhythmias, and sinus arrest). The number of electrocardiographic abnormalities decreased after surgery but new abnormalities
appeared in some patients. Systolic pulmonary arterial pressure significantly decreased in the group of patients in whom OSAHS
disappeared after surgery. Daytime sleepiness persisted after surgery in most patients. Conclusion: Bariatric surgery effectively
reduces respiratory disturbances during sleep and improves pulmonary hypertension. Electro cardiographic abnormalities change
after surgery. Daytime sleepiness appeared not to be related to respiratory disturbances during sleep. 相似文献
100.
Effect of resisted exercise on autonomic cardiac modulation in elderly women: STROBE-compliant study
Naerton Jos Xavier Isidoro Fernando Rocha Oliveira Rodrigo Daminello Raimundo 《Medicine》2022,101(10)
Heart rate variability (HRV) is an important cardiac health marker, with lower values indicating a reduction in vagal control of cardiac rhythm and decreasing significantly with advancing age. In this study, we evaluated the effects of strength exercises for the upper and lower limbs on cardiac autonomic modulation in elderly women.We registered 29 participants using a portable RS800CX heart rate monitor to record the RR intervals. For the collection of HRV data, the volunteers remained seated at rest for 10 minutes. After the rest period, the participants performed the exercises. Immediately after the exercise protocol, the subjects remained seated at rest for 30 minutes. HRV indices were analyzed in the following periods: rest, 0 to 10 minutes, 5 to 10 minutes, 10 to 20 minutes, and 20 to 30 minutes. Systolic arterial pressure and diastolic arterial pressure were measured in the following periods: rest, immediately after exercise, and 30 minutes after exercise.Regarding the mean of the RR intervals, heart rate, and indexes of the time and frequency domains surveyed, there were no statistically significant differences between the 4 moments in the protocols for upper and lower limbs. No significant differences were found in systolic and diastolic pressures between the 3 time points surveyed in the protocols for the upper and lower limbs.Resistance exercises performed with low-intensity loads and a greater number of repetitions did not promote significant variations in cardiac autonomic modulation and blood pressure levels, showing good safety in elderly women. 相似文献