Search results for "PHASE"
showing 10 items of 6344 documents
Performance of amines as silanol suppressors in reversed-phase liquid chromatography
2016
In reversed-phase liquid chromatography, cationic basic compounds yield broad and asymmetrical peaks, as a result of their ionic interaction with the anionic free silanol groups present in the silica-based stationary phases (commonly derivatised with C18 groups). A simple way to improve the peak shape is the addition to the hydro-organic mobile phase of a reagent (usually called additive) with cationic character. This associates with the stationary phase to prevent the access of analytes to the free silanol groups. Cationic additives may interact electrostatically with the anionic silanols. The hydrophobic region of the additive may also associate with the alkyl chains bound to the stationa…
Dry adsorbed emulsion: 1. Characterization of an intricate physicochemical structure
2000
Abstract A recent solid pharmaceutical form called “Dry Adsorbed Emulsion” (DAE) was characterized in morphological and structural fields. A DAE is an intricate system initiated by a water‐in‐oil emulsion including the active drug (i.e., theophylline). Each emulsion phase is adsorbed on pulverulent adsorbents with a suitable polarity (silica) to obtain a free‐flowing powder with nonporous particles of size from 125 to 710 μm, with small specific surface area and a spherical shape. Different methods, such as scanning electron microscopy combined with chemical microanalysis, dying tests, and electron spin resonance studies, allow the formulator to follow the behavior of DAE aqueous and oily p…
Magnetic In-Tube Solid Phase Microextraction
2012
We report a new in-tube solid phase microextraction approach named magnetic in-tube solid phase microextraction, magnetic-IT-SPME. Magnetic-IT-SPME has been developed, taking advantage of magnetic microfluidic principles with the aim to improve extraction efficiency of IT-SPME systems. First, a magnetic hybrid material formed by Fe(3)O(4) nanoparticles supported on SiO(2) was synthesized and immobilized in the surface of a bared fused silica capillary column to obtain a magnetic adsorbent extraction phase. The capillary column was placed inside a magnetic coil that allowed the application of a variable magnetic field. Acetylsalicylic acid, acetaminophen, atenolol, diclofenac, and ibuprofen …
High-resolution physisorption techniques for the characterization of adsorbents and catalysts
1991
Abstract High-resolution physisorption techniques performed in the continuous volumetric mode have been developed to investigate the surface and pore structure properties of porous solids. Physisorption data on well-defined microporous solids (zeolites and aluminophosphates) provide novel information on the mechanism of micropore filling, the behavior of the adsorbed phase and the pore structure of the adsorbent. The combination of physisorption with high-resolution analytical techniques such as calorimetry and neutron diffraction further expands our knowledge and understanding of physisorption processes. The results are not only important for fundamental research but can be applied in the …
The Use of 15N NMR for the Understanding of Nitrogen Physisorption.
1994
Abstract Nitrogen adsorption at liquid nitrogen temperature, 77K, is universally employed to determine pore dimensions. The nature of nitrogen physisorbed within the micropores of ZSM-5 zeolite was studied by in situ15N NMR as it depends on the partial pressure of the nitrogen and the temperature above and below 77K. An increase in the volume of adsorption of nitrogen at 77K occurs at a relative pressure of ~0.18 for this zeolite. The nature of the nitrogen was studied below and above this increase in nitrogen adsorption. We find that two states (phases) of nitrogen are evident. We conclude that two phases can be present but that a solid phase of nitrogen is not evident even as the temperat…
Phase II Study of Taselisib (GDC-0032) in Combination with Fulvestrant in Patients with HER2-Negative, Hormone Receptor–Positive Advanced Breast Canc…
2018
AbstractPurpose: This single-arm, open-label phase II study evaluated the safety and efficacy of taselisib (GDC-0032) plus fulvestrant in postmenopausal women with locally advanced or metastatic HER2-negative, hormone receptor (HR)-positive breast cancer.Patients and Methods: Patients received 6-mg oral taselisib capsules daily plus intramuscular fulvestrant (500 mg) until disease progression or unacceptable toxicity. Tumor tissue (if available) was centrally evaluated for PIK3CA mutations. Adverse events (AE) were recorded using NCI-CTCAE v4.0. Tumor response was investigator-determined using RECIST v1.1.Results: Median treatment duration was 4.6 (range: 0.9–40.5) months. All patients expe…
Multicenter Phase II Study of Lurbinectedin in BRCA-Mutated and Unselected Metastatic Advanced Breast Cancer and Biomarker Assessment Substudy
2018
Purpose This multicenter phase II trial evaluated lurbinectedin (PM01183), a selective inhibitor of active transcription of protein-coding genes, in patients with metastatic breast cancer. A unicenter translational substudy assessed potential mechanisms of lurbinectedin resistance. Patients and Methods Two arms were evaluated according to germline BRCA1/2 status: BRCA1/2 mutated (arm A; n = 54) and unselected ( BRCA1/2 wild-type or unknown status; arm B; n = 35). Lurbinectedin starting dose was a 7-mg flat dose and later, 3.5 mg/m2 in arm A. The primary end point was objective response rate (ORR) per Response Evaluation Criteria in Solid Tumors (RECIST). The translational substudy of resist…
Outcomes of single versus double hormone receptor–positive breast cancer. A GEICAM/9906 sub-study
2018
Abstract Background Retrospective data suggest better outcomes for patients with double hormonal receptor (oestrogen [ER] and progesterone receptor [PgR])–positive (dHR+) early breast cancer, compared with single hormonal receptor–positive, sHR+, (ER+/PgR– or ER–/PgR+) disease. Here, we evaluate the classification according to intrinsic subtypes and clinical outcomes of sHR+ versus dHR+ in HER2-negative breast cancer patients enrolled in GEICAM/9906 study ( NCT00129922 ). Methods Archival tumours were retrieved retrospectively for the analysis of ER, PgR and HER2 status and classified into intrinsic subtypes using the PAM50 gene expression assay. Disease-free survival (DFS) and overall surv…
Cyclophosphamide plus Epidoxorubicin and 5-Fluorouracil with Folinic Acid as a Novel Treatment in Metastatic Breast Cancer: Preliminary Results of a …
1991
Twenty consecutive patients with advanced breast cancer were treated with a combination of cyclophosphamide 600 mg/m2 i.v. on day 1, epidoxorubicin 75 mg/m2 on day 1, and 5-fluorouracil 375 mg/m2 i.v. with folinic acid 200 mg/m2 i.v. on days 1----3. The overall response rate was 60%, with 10% of patients showing a complete response with a mean duration of 11.1 + months, and 50% of patients a partial response of 7.4 + months. A stabilization of 5.2 + months was obtained in 20% of cases, while 20% of patients progressed. The most frequently observed toxicity was leukopenia, while expected mucosal toxicities were rather mild.
Emotional interference and attentional processing in premenstrual syndrome
2017
Abstract Background and objectives Premenstrual syndrome (PMS) is characterized by menstrual cycle-related affective, behavioral, and/or somatic symptoms. By applying the emotional Stroop task (EST) the current study examined if changes in processing emotional information, which have been demonstrated in affective disorders, are also present in PMS. Methods Via online screening, telephone interviews, and daily records over two months 55 women for the PMS group (on the basis of the specific inclusion criteria and a prospectively confirmed PMS) and 55 ‘non-PMS’ controls were recruited. All participants completed three emotional Stroop tasks (EST) with neutral and negative word, picture, and f…