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Results for “parameter optimization”

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At least 1,081 records · Page 60Linked to original sources

PubMed2005

[Optimal reconstruction of destructed teeth by pin constructions].

327 patients with dentures supported by 318 pulpless teeth reinforced by pin constructions were under observation. Main types of complications after pin use were identified. By math simulation the system "covering construction-artificial stump-root pin-root of the tooth" was studied for teeth 11, 13, 15, 16, 41, 43, 45, 46 in two projections--vestibulo-oral and mesio-distal. Margins of strength properties of teeth armed by special pin constructions (made as individual casting) and artificial stump with standard pins made of different materials were determined. Optimal parameters of height and width of off-root part and intra-root pin sizes in different teeth groups in conformity with their individual anatomic peculiarities were established.

Dental Pins↗

PubMed2006

[Methodological quality assessment of clinical trials in traditional Chinese medicine: the principles of evidence-based medicine].

The quality of clinical trials in traditional Chinese medicine (TCM) was analyzed with respect to their methodology and outcome assessment according to the concepts of evidence-based medicine (EBM). It was suggested that the essential methodological principles of EBM should be applied in clinical trials of TCM, including randomization, control and blindness. The sample size estimation, optimal parameter selection for outcome assessment, compliance and intention-to-treat analysis are all important aspects of randomized controlled trials. To bring the benefits of EBM into clinical trials will improve the quality of research in TCM and also promote international co-operation and communications. It is necessary to establish an assessment system of clinical outcome for TCM on the basis of EBM in order to evaluate the efficacy and safety of TCM objectively and scientifically.

Evidence-Based Medicine↗

PubMedDate not supplied

[The effect of dispersed silicon dioxide--aerosil A-300--on the growth of Saccharomyces cerevisiae yeasts].

High-dispersed silicon dioxide--aerosil A-300 has been studied for its effect on the growth of yeast Saccharomyces cerevisiae. It is shown that at heterophase cultivation of these microorganisms under periodical conditions introduction of aerosil A-300 induces a decrease of the lag phase duration and an increase of the maximum specific growth rate and economic coefficient of the carbon substrate utilization. This high-dispersed material has exerted the similar effect under the conditions of chemostatic cultivation. Optimal parameters of this process are determined.

Culture Media↗

PubMed2006

High energy density processing of a free form Nickel-alumina nanocomposite.

The development of a free form bulk Nickel reinforced Alumina matrix nano composites using Air Plasma Spray and laser processing has been presented. The process consumes less time and requires further minimal machining and therefore is cost effective. The relative differences in using APS over laser processing in development of bulk metal-ceramic nanocomposites have been discussed. The process intricacies involved during processing such as material specific mandrel selection, plasma-particle interaction are highlighted. Electroless coating has been used to uniformly disperse Nickel in alumina matrix as a source material. The electroless Ni coated alumina particles are subjected to both laser processing and Air Plasma Spraying with optimized parameters. Consolidation by laser processing could not be achieved as the laser beam was reflective to Nickel. On the other hand, APS Ni-alumina nanocomposite with a cylindrical shape of 1.2" OD x 1" ID x 1.5" length has been fabricated with minimum or no surface defects. HRTEM pictures revealed the nanostructure retention thereby corroborating the fact that bulk nanostructures can be made using Air Plasma Spray. XRD analysis confirmed the phase transformation from alpha alumina to gamma alumina and oxidation of Ni to NiO. Subsequent reduction of NiO to metallic nickel using hydrogen atmosphere has also been demonstrated. Mechanical properties such as, hardness (1025 HV) and fracture toughness (5 MPa m1/2) for the nanocomposite are presented herein.

Aluminum Oxide↗

PubMedDate not supplied

[E-health application for home monitoring of neuro-muscular rehabilitation].

In many medical fields the recovery of muscular activity or its improvement up to the level of the optimal parameters is required. Apart from the classical solution for rehabilitation (physical exercises) the use of electrical stimulation has become quite frequent of late. The paper presents an interface that detects the electromyographic (EMG) activity, assesses it, and generates appropriate electrical stimuli, by means of a specific type of fuzzy control system, in order to control the dynamics of the EMG. The proposed interface will detect the motion and muscular activity, it will evaluate and generate the electrical stimulus using a fuzzy system tuned by dynamic of motion. The application will transmit e-Health information to the physician via Internet, synthetic, at request using TCP/IP stack and SMS services for wireless communication.

Electromyography↗

PubMed2006

[Using compost of agricultural solid waste to produce organic-inorganic compound fertilizer].

Techniques of compound fertilizer production from solid waste compost were studied. Different ratio of water moisture, proportion between organic and inorganic and infection of different granularity to the effect of granulation is separately determined through experiments at the pilot scale in the field. The optimal parameters of the techniques are determined. The moisture content is 35%-40%; the rate of organic matter is 80%-90%; granularity is 20 mu. According the data of the organism's concentration, height and weight in crop, the crop was fertilized compound fertilizer is batter than chemical fertilizer. And the ability of increasing the production of the compound fertilizer was testified.

Agriculture↗

PubMed2006

[Experimental study of non-invasive percutaneous electrical stimulator for treatment of obstructive sleep apnea syndrome and its clinical effect].

To study the stimulation of the genioglossus with percutaneous biphasic current pulses as a new therapeutical method to treat the obstructive sleep apnea syndrome (OSAS), polysomnography (PSG) was used to synchronously monitor the patient. When OSAS was occurring, the stimulation with the optimal parameter was given in time to make the tongue move forward, the glossopharyngeal airway dilated, the resistance of the upper respiratory tract reduced, the hypoxia at night to be improved and the sleeping structure to be ameliorated because of the function of the dilated muscle of the upper airway. The results of the clinical therapeutic effect indicated that 17 of 22 patients with OSAS had cured effects, 2 of whom improved and 3 of whom were without effect. The effective rate was 77.27%. It is preliminarily proved that this is a new method in the treatment of patients suffered from OSAS.

Adult↗

PubMed2006

Enhanced oligonucleotide delivery to mouse retinal cells using iontophoresis.

PURPOSE: To study the combination of oligodeoxynucleotides (ODNs) intravitreous injection and saline transpalpebral iontophoresis on the delivery of ODNs to photoreceptors in the newborn rd1/rd1 mice. METHODS: Cathodal or anodal transpalpebral iontophoresis (1.43 mA/cm(2) for 5 min) was applied to eyes of postnatal day 7 (PN7) rd1/rd1 mice immediately before the intravitreous injection of ODNs. The effect of cathodal iontophoresis after ODNs injection was also evaluated. The influence of current intensity (0.5, 1.5, and 2.5 mA) was assayed with cathodal iontophoresis performed prior to ODNs injection. The duration of current-induced facilitation of ODNs delivery to photoreceptors was evaluated for 6 h following iontophoresis. One group of control eyes received cathodal iontophoresis prior to the intravitreous injection of phosphate buffered saline (PBS) or hexachlorofluorescein (Hex). The second control group received ODN or Hex intravitreous injection without iontophoresis. The penetration of fluorescent ODNs in the outer nuclear layer (ONL) was quantified by image analysis of the ONL fluorescence intensity on cryosection microphotographs. Integrity of ODN was assessed using acrylamide gel migration after its extraction from the retina of treated mice. The integrity of retinal structure, 1 and 24 h after iontophoresis, was analyzed using light and electron microscopy. RESULTS: Transpalpebral anodal or cathodal saline iontophoresis enhanced the penetration of ODNs in all retinal layers. Cathodal iontophoresis was more efficient than anodal iontophoresis in enhancing the tissue penetration of the injected ODN. Photoreceptor delivery of ODN was significantly higher when cathodal saline transpalpebral iontophoresis was applied prior than after the injection. The extent of enhanced tissue penetration decreased in parallel to the increased interval between iontophoresis application and the intravitreous injection. Current of 1.5 mA was safe and optimal for the delivery of ODNs to the ONL. One hour after iontophoresis followed by injection, ODN extracted from the retina of treated eyes remained intact. Histology and electron microscopy observations demonstrated that iontophoresis using the optimal parameters did not induce any permanent tissue alterations or structure damage. CONCLUSIONS: Saline transpalpebral iontophoresis facilitates the penetration of injected ODNs in photoreceptors for at least 3 h. This method may be considered for photoreceptor targeted gene therapy.

Animals↗

PubMed1991

[Roentgen diagnosis of pulmonary complications following allogeneic bone marrow transplantation--application of and experience with digital luminescence radiography].

Pulmonary complications exercise a decisive influence on the prognosis of leukaemia patients after bone marrow transplantation. Very early diagnosis is a mandatory prerequisite to successful therapeutic intervention. Of great importance besides the clinical findings and bronchoalveolar lavage is the analysis of the x-ray morphology of pneumonic infiltrates to narrow down the differential diagnostic spectrum. Since the patients are at high risk of infection, they are under isolated care, so that x-ray examinations can only be performed by means of projection radiography using mobile units. Due to these difficulties in performing relevant radiography the required optimal and constant image quality cannot be achieved by means of conventional x-ray film, so that very early detection of pulmonary complications is not always possible. The use of digital luminescence radiography (DLR) with luminescent storage foils enables a highly constant and hence comparable image quality thanks to increased image dynamics, a larger area of the examined object, and histogram evaluation of the image data for determining the optimal parameters for assessment. In addition, details can be better identified to supply answers to specific questions, because the image can be reprocessed to select relevant image parameters by monitoring. Pulmonary complications in 86 patients were analysed retrospectively. These patients had received an allogeneic bone marrow transplant for acute myeloic leukaemia, after they had been treated with high-dose radio-/chemotherapy. The x-ray morphology, clinical and sometimes autopsy findings were correlated with the occurrence of pulmonary complications subsequent to bone marrow transplant.

Adolescent↗

PubMed1991

[Determination of serum activity of placental alkaline phosphatase].

The authors have developed an enzymatic method for the measurement of serum placental alkaline phosphatase (PLAP) based on the hydrolysis of paranitrophenyl phosphate into para-nitrophenol. The specificity for the isoenzyme involved is achieved by means of its characteristics thermostability. After one hour incubation at 60 degrees C, PLAP still maintains its full activity, while other isoenzymes are completely inactivated. The sensitivity of the method was improved (less than 1 U/l) by optimizing parameters such as the volume of specimen, the nature of the buffer (2-methyl-amino-ethanol), the reaction time and the pH. Analysis of the method performances has revealed a lower detection limit of 0.12 U/l, a linearity from 0 to 50 U/l, a precision lower than 10% for most of the analytical range and a complete enzyme recovery. The reference range was estimated from 0 U/l to 0.33 U/l in a group of 125 non-smokers without any cancerous disease.

Alkaline Phosphatase↗

PubMed1991

[Laser seromyotomy of the stomach in duodenal ulcers].

The use of laser surgical equipment permits to simplify considerably a method of gastric seromyotomy. On the basis of the results of treating 38 patients, the optimal parameters of laser energy, used in dissection of the gastric wall, are recommended, the advantages and shortcomings of the different sources of radiation are studied.

Duodenal Ulcer↗

PubMed1991

[The role of computed tomography in dystrophic diseases of the hip joint].

Computer tomography data on 124 patients with degenerative-dystrophic diseases of hip joint of different etiology are presented. As indicated the results of investigations, computer tomography of hip joint is the effective method of early diagnosis of femoral head aseptic necrosis. Computer tomography application allows to detect precise location, size and character of the pathology process in hip joint and propose the optimal parameters of surgical correction. Femoral head densitometry in case of femoral head aseptic necrosis revealed the curves of two types: with unimodal and bimodal density distribution. Patients with bimodal histograms demonstrated worse results of surgical treatment.

Acetabulum↗

PubMed1990

[Multifactor analysis of the combined use of an antibiotic and a low molecular weight immunomodulator of microbial origin in experimental plague infection].

Multifactorial analysis of the combined effect of rifampicin and a low molecular immunomodulator of microbial origin in experimental plague infection was performed. Synergism of the antibiotic used in the subtherapeutic doses and the immunomodulator was shown. By the results of the study polynomial statistic models of the second order describing the survival rate and average life-span of the experimental animals were developed and nomographs (equal level curves) were plotted for rapid estimating the therapy quantitative parameters. Optimization of the combined use of rifampicin and the immunomodulator on the basis of the multifactorial analysis was achieved.

Adjuvants, Immunologic↗

PubMed1990

[Determination of abrasive properties of toothpastes by means of copper abrasion].

The results are presented of the investigations of the proposed method for determination of the abrasive properties of toothpastes and raw materials used for their production. The method is based on brushing of copper surface with the studied paste in a device of own design, followed by chemical analysis of copper content in the mass after brushing. The optimal parameters of the work of the abrasive device were determined and the method for determination of copper content is described. For chemical analysis absorption spectroscopy in visible light and atomic absorption spectroscopy were used. The advantages of the proposed method of abrasive force determination was discussed comparing them to those of radioisotope assay.

Copper↗

PubMed1990

[A radiobiologic model for optimizing the radiotherapy of malignant tumors within the framework of the Ellis concept].

A radiobiological model is represented, that allows to estimate the number of surviving tumor cells at the end of radiotherapeutic series with equivalent NSD. On this base a programme for computer-assisted calculation was elaborated. The programme allows to estimate optimal conditions of dose fractionation, in which a devitalization of a maximum number of tumor cells is guaranteed. For the radiotherapy of radioresistant tumors, characterized by the extrapolation number n greater than 2, optimal parameters can be obtained by means of simple mathematical formulas. The elaborated model allows to increase the efficiency in radiotherapy of malignant tumors with known radiobiological parameters.

Humans↗

PubMed1990

[Examination of the rectosphincteric reflex by means of endoscopic electrical stimulation. A new device].

An endoscopic electrical stimulation method (the new method) for the examination of the rectosphincteric reflex was devised to overcome difficulties attributable to the manometric method using balloon stimulation. Safety of the electrical stimulation under the conditions used routinely, was confirmed symptomatically and histologically. It was found that the optimal parameters of electrical stimulation to obtain the recto-sphincteric reflex were: 1 ms, 20 Hz, 5 to 7mA, and for 3 sec. The degree of the reflex relaxation became less and the time lag of the response to the stimulation became longer, as the distance of the stimulation site from the anal verge was increased. These relationships were significant. In the cases which received anterior resection of the rectum, the rectosphincteric reflex was examined using the new method. In 12 of 39 cases the recto-sphincteric reflex was induced by stimulation at the oral side of the anastomosis. In all of them the reflex was observed at 9 or more months postoperatively. Incidence of postoperative reflex appearance tended to be higher after end-to-end anastomosis than after side-to-end anastomosis. In two cases which received Duhamel-Okamoto's operation and in one which received Soave-Denda's operation, it was possible to analyze the relationship between the stimulating site and presence or absence of the reflex-like phenomenon.

Adult↗

PubMed1987

Cancer therapy by biological response modifiers.

Biological response modifiers (BRMs) are agents or approaches that modify the relationship between the tumor and host by modifying the host's biological responses to tumor cells, with resultant therapeutic effects. BRMs include immunomodulators and components of the immune system, e.g. cytokines, antibodies and effector cells. A central challenge in the development of BRMs for therapy of cancer patients is to determine the main mechanism of action of each agent and by monitoring for effects of treatment on the key parameters, optimize the treatment protocol. The experience to date with interferons and with interleukin-2 (IL-2) is summarized, to illustrate both the promise of BRMs and the difficulties in determining the optimal therapeutic regimen and in turn this potential for more effective treatment of cancer. A new sequence of clinical trials for clinical evaluation of BRMs is described, with an emphasis on treatment of patients with minimal tumor burden.

Animals↗

PubMed1989

The immunogenicity of soluble haptenated polymers is determined by molecular mass and hapten valence.

T cell-independent Ag are believed to stimulate antibody formation in the relative absence of Ag processing and T cell help. Previous studies on the type 2 T cell independent (TI-2) Ag DNP-polyacrylamide, have shown that when one systematically varies the molecular mass and hapten valence, the immunogenic potential of this type of molecule depends on definable molecular characteristics. It was found that to be immunogenic, these molecules had to exceed a threshold molecular mass of 100,000 Da and a threshold hapten valence of 20. The present study was undertaken to determine whether such findings could be generalized to other molecules belonging to the TI-2 class of Ag. The molecular characteristics of five chemically different fluoresceinated (FL)-polymers were systematically varied, and their ability to stimulate an IgM antihapten immune response was measured. The polymers used as carriers were carefully size-fractionated and consisted of one natural polymer (dextran), one modified natural polymer (carboxymethyl cellulose), and three synthetic polymers (Ficoll, polyvinyl alcohol, and polyacrylamide). The carriers varied in physical structure from the highly cross-linked Ficoll, to the somewhat branched dextran, to the linear polyacrylamide, carboxymethyl cellulose, and polyvinyl alcohol. Polymers were haptenated with FL and size-fractionated so as to yield a panel of molecules with varying molecular mass, hapten valence, and hapten density. Anti-FL IgM response to these haptenated polymers was measured in vivo after i.p. injection of the FL-polymer in saline, and measured in vitro after culture with unfractionated spleen cells from naive mice. In agreement with the previous studies on DNP-polyacrylamide, it was found that to be immunogenic, each of the FL-polymers had to exceed a comparable threshold value of molecular mass and of hapten valence. Optimal immunogenicity occurred when the FL-polymers had values of mass and hapten density lying within a predictable range. Immunogenicity decreased when these optimal parameters were substantially increased or decreased. We conclude that the immunogenicity of soluble haptenated polymers depends on predictable physical molecular characteristics, and is relatively independent of the chemical composition and conformation of the carrier polymer.

Animals↗