Search results for "Time factor"
showing 10 items of 3219 documents
Optimal selection of individuals for repeated covariate measurements in follow-up studies
2016
Repeated covariate measurements bring important information on the time-varying risk factors in long epidemiological follow-up studies. However, due to budget limitations, it may be possible to carry out the repeated measurements only for a subset of the cohort. We study cost-efficient alternatives for the simple random sampling in the selection of the individuals to be remeasured. The proposed selection criteria are based on forms of the D-optimality. The selection methods are compared with the simulation studies and illustrated with the data from the East–West study carried out in Finland from 1959 to 1999. The results indicate that cost savings can be achieved if the selection is focuse…
Evaluation of the antiproliferative, proapoptotic, and antiangiogenic effects of a double-stranded RNA mimic complexed with polycations in an experim…
2015
Objective To assess the antiproliferative, proapoptotic, and antiangiogenic effects of the double-stranded RNA mimic polyinosine-polycytidylic acid (pIC) complexed with polyethylenimine [pIC PEI ] in xenografted human leiomyomas. Design Heterologous leiomyoma mouse model. Setting University-affiliated infertility center. Animal(s) Ovariectomized and hormone-replaced nude mice (n = 16) who received human leiomyoma fragment transplantation. Intervention(s) Leiomyoma fragments placed in the peritoneum of 5-week-old nude female mice and treated with the vehicle (n = 8) or 0.6 mg/kg [pIC PEI ] (n = 8) for 4 weeks. Main Outcome Measure(s) The size of the leiomyoma implants, and cellular prolifera…
Detection of IgM antibodies specific for measles virus by capture and indirect enzyme immunoassays.
1995
Summary During a measles outbreak, 112 serum specimens from 88 hospitalized patients were received in our laboratory for investigation of a morbilliform rash. These specimens (88 acute- and 24 convalescent-phase) were tested for the presence of measles-specific IgM antibodies by a capture EIA (enzyme immunoassay) using peroxidase-conjugated measles virus antigens and by an indirect EIA. Commercially available indirect EIA kits for measles-specific IgM antibodies were also used and compared with our homemade EIAs. Specificity studies included a collection of serum specimens containing rheumatoid factor, antinuclear antibodies or IgM antibodies specific to other viruses, and sera from blood d…
From laparoscopic assisted radical vaginal hysterectomy to vaginal assisted laparoscopic radical hysterectomy
2011
Radical hysterectomy with pelvic lymphadenectomy is the standard surgical treatment for patients with early stage cervical cancer. The majority of radical hysterectomies are performed with the open technique. However, laparoscopic, combined laparoscopic and vaginal, and robotic-assisted approaches may also be used. Compared with the abdominal radical hysterectomy (ARH), laparoscopic techniques are associated with less blood loss, shorter hospital stay, better cosmesis, and faster recovery. A further breakthrough in laparoscopic technique can only be made if safety and oncological clearance are comparable with ARH. We describe the technique and results of laparoscopic assisted radical vagina…
Long-term outcome prediction by clinicopathological risk classification algorithms in node-negative breast cancer--comparison between Adjuvant!, St G…
2009
Background: Defining risk categories in breast cancer is of considerable clinical significance. We have developed a novel risk classification algorithm and compared its prognostic utility to the Web-based tool Adjuvant! and to the St Gallen risk classification. Patients and methods: After a median follow-up of 10 years, we retrospectively analyzed 410 consecutive node-negative breast cancer patients who had not received adjuvant systemic therapy. High risk was defined by any of the following criteria: (i) age 2 cm. All patients were also characterized using Adjuvant! and the St Gallen 2007 risk categories. We analyzed disease-free survival (DFS) and overall survival (OS). Results: The Node-…
Time-Varying Surrogate Data to Assess Nonlinearity in Nonstationary Time Series: Application to Heart Rate Variability
2009
We propose a method to extend to time-varying (TV) systems the procedure for generating typical surrogate time series, in order to test the presence of nonlinear dynamics in potentially nonstationary signals. The method is based on fitting a TV autoregressive (AR) model to the original series and then regressing the model coefficients with random replacements of the model residuals to generate TV AR surrogate series. The proposed surrogate series were used in combination with a TV sample entropy (SE) discriminating statistic to assess nonlinearity in both simulated and experimental time series, in comparison with traditional time-invariant (TIV) surrogates combined with the TIV SE discrimin…
Improving ovarian tissue cryopreservation for oncologic patients: slow freezing versus vitrification, effect of different procedures and devices.
2013
Objective To compare slow freezing (SF) with four vitrification techniques (VT) for cryopreservation of ovarian tissue (OT) and to evaluate the best protocol for human OT in a xenograft model. Design Experimental study. Setting University hospital. Patient(s) Patients undergoing fertility preservation. Animal(s) Ovariectomized nude mice. Intervention(s) Cryopreservation of bovine OT after SF and four VTs (VT1, VT2, VT3, and VT4) by combining two cryoprotectant vitrification solutions (VS1 and VS2) and two devices (metallic grid and ethyl vinyl acetate bag), after which the cryopreservation of human OT by SF and VT1 and xenograft into nude mice. Main Outcome Measure(s) Follicular densities, …
Effect of cost on early removal of contraceptive implants: a prospective cohort study
2019
OBJECTIVES To evaluate the effect of the cost of subdermal etonogestrel implant (SEI) on the continuation rate one year after insertion, and to assess the reasons given by users to remove the implant before the expiration date. METHODS Prospective cohort study conducted among 265 women who chose the SEI as a contraceptive method in a sexual and reproductive health center in the eastern region of Spain, between October/2012 and October/2017. The sample was divided into two cohorts depending on the cost of the implant for the user (free-of-charge or requiring partial payment). Kaplan-Meier survival curves were used to compare the cumulative removal rates of free implants with partially paid i…
Perceiving musical tension in long chord sequences
1999
We attempted to predict perceived musical tension in longer chord sequences by hierarchic and sequential models based on Lerdahl and Jackendoff's and Lerdahl's cognitive theories and on Parncutt's sensory-psychoacoustical theory. Musicians and nonmusicians were asked to rate the perceived tension of chords which were drawn either from a piece composed for the study (Exp. 1) or from a Chopin Prelude (Exps. 2-4). In Exps. 3 and 4, several experimental manipulations were made to emphasize either the global or the local structure of the piece and to verify how these manipultions would affect the respective contribution of the models in the ratings. In all experiments, musical tension was only w…
Photobleaching effects onin vivoskin autofluorescence lifetime
2015
The autofluorescence lifetime of healthy human skin was measured using excitation provided by a picosecond diode laser operating at a wavelength of 405 nm and with fluorescence emission collected at 475 and 560 nm. In addition, spectral and temporal responses of healthy human skin and intradermal nevus in the spectral range 460 to 610 nm were studied before and after photobleaching. A decrease in the autofluorescences lifetimes changes was observed after photobleaching of human skin. A three-exponential model was used to fit the signals, and under this model, the most significant photoinduced changes were observed for the slowest lifetime component in healthy skin at the spectral range 520 …