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At least 1,369 records · Page 76Linked to original sources
PubMed1992

[Quality assessment of the traditional Chinese medicine gentian by chemical pattern recognition].

Methanol extracts of 38 samples of the traditional Chinese medicine gentian of different origin were prepared. Data reflecting their chemical constituents as a whole were obtained by HPLC. The Chinese Pharmacopoeia (1990) specified four species of the getiana as authentic. Some samples from the authentic and non-authentic gentian were used as the training set of pattern recognition. Chemical features of the gentian samples were selected from among the matching data of HPLC by the SIMCA program. Finally, the selected chemical features were displayed as stars in a semicircular polar coordinate system, resulting in a constellation graph. Quality assessment of the traditional Chinese medicine gentian was accomplished by recognizing the position and path of the stars in the constellation graph. The clusters of the gentian samples in the constellation graph obtained from the HPLC features were consistent with and complement to their plant taxonomy. The vivid graph demonstrated that pattern recognition via chemical constellation promises well a reliable method for assessing traditional Chinese medicines.

Chromatography, High Pressure Liquid↗
PubMed2004

[Morphologic characteristics of anterior crossbite in early permanent dentition reviewed by superimposition on the template].

PURPOSE: To establish a computer-processing module to first, eliminate the factors which mislead the diagnosis of anterior crossbite and second, superimpose the individual tracing on the template to review the patient's morphologic characteristics. METHODS: First, the module would process the following steps:1.to create three templates; 2.to move the functional-shift-mandible posteriorly; 3.to standardize the potential of vertical dimension;4.to select a suitable template for superimposition; 5.to standardize the sizes of individual graph and template. Second, the module would process the five-step superimpositions: 1. X axis was superimposed and S were registered to measure the distances between Ptm points and Ar points on X axis; 2. X axis was paralleled and Ptm were registered to measure the distance between A points on X axis; 3. X axis was paralleled and A points were registered to measure the difference of anterior area between the mandibular graphs; 4.mandibular planes were superimposed and Po was registered to show the mandibular form variation; 5. Ar-Gn lines were superimposed and Ar was registered to measure the difference between the mandibular graphs. RESULTS: The module which could complete these steps was produced. With its help, the individual graph could be diagnosed with the position of maxilla and mandible, the amounts of maxillary discrepancy and jaws' dysplasia, the mandibular form and size variation. CONCLUSIONS: The module could eliminate the factors which mislead the diagnosis and review the morphologic characteristics of anterior crossbite in early permanent dentition.

Dentition, Permanent↗
PubMed2006

[Contribution of medical technologists in team medical care of diabetics].

For the effective treatment of diabetic mellitus (DM), patients are encouraged to self-manage their disease according to the doctor's instructions and advice from certified diabetes educators (CDE) and other comedical staff. Therefore, the cooperation of medical staff consisting of a doctor, CDE, nurse, pharmacist, dietitian, and medical technologist is important for DM education. Medical technologists licensed for CDE (MT-CDE) have been participating in the DM education team in Kobe University Hospital since 2000. MT-CDE are in charge of classes for medical tests, guidance for self-monitoring of blood glucose and teaching how to read the fluctuation graph of the blood glucose level in the education program for hospitalized DM patients. MT-CDEs teach at the bedside how to read the results of medical tests during the first few days of hospitalization using pamphlets for medical tests. The pamphlets are made comprehensible for patients by using graphics and photographs as much as possible. It is important to create a friendly atmosphere and answer frank questions from patients, since they often feel stress when having medical tests at the early stage of hospitalization. This process of questions and answers promotes their understanding of medical tests, and seems to reduce their anxiety about having tests. We repeatedly evaluate their level of understanding during hospitalization. By showing them the fluctuation graph of the glucose level, patients can easily understand the status of their DM. When prescriptions are written on the graph, their therapeutic effects are more comprehensible for the patients. The items written on the graph are chosen to meet the level of understanding of each patient to promote their motivation. In summary, the introduction of MT-CDE has been successful in the education program for DM patients in our hospital. We plan to utilize the skills and knowledge of MT-CDE more in our program so that our DM education program will help patients cope with life with DM.

Blood Glucose Self-Monitoring↗
PubMedDate not supplied

[Medical legal aspects of the requirement to report noise-induced hearing loss notified to INAIL to the judicial authorities].

BACKGROUND: Law 689/81 redefined how personal lesions could be prosecuted by means of explicit mention of occupational diseases among the type of offences subject to mandatory reporting. The high prevalence of noise-induced hearing loss (NIHL) among occupational diseases has monopolized attention towards identification of a method that can define the penal limits of this occupational disease; however, up to now no single univocal approach exists. For this reason operators in this field are perplexed as to the requirement of reporting judicial authorities (J.A.). On the other hand, the great changes that have occurred in compensation of occupational diseases by INAIL (sentence 179/88 of the Constitutional Court) and the evaluation of the same in terms of biological impairment (Law D.Lgs. 38/00 and Law D.M. 12.7.00) have led to an ample and accurately assessed protection against, work-related hearing loss. OBJECTIVES AND METHODS: From this perspective the authors analysed 52 cases of NIHL reported to INAIL. They compared the assessments made according to Law D.M. 12.7.00 and the guidelines for reporting to the J.A. according to four different methods generally used in the criminal field: Benciolini, Merluzzi, SIMLII guide lines and SIO guidelines. By stressing the need for a preliminary qualitative evaluation of NIHL in the penal report, the authors. restricted the analysis to the quantitative aspect with technically compatible graphs. RESULTS: Processing the data resulting from application of the different methods, led to the assumption that audiometric graphs that showed a percentage of biological impairment according to Law D.M. 12.7.00 higher than 2.40% must always be reported to the JA. For audiometric graphs that show impairment of less than 0.5% recommendations to report tare rather sporadic. For the graphs with intermediate values recommendations to report to the J.A, which are always present in at least one of the methods, are not constant, and in particular there is no linear correlation between the percent grading of biological impairment and the recommendation to report; this is probably due to a difference in concept of the various methods which reflects on the respective scale of values. CONCLUSIONS: On the basis of these results the authors suggest that reporting to the judicial authority can be recommended for all those cases whose quantification, according Marello's schedule, is higher than 0.5%, as these cases can, according to the penal code, supplement assessment of impairment.

Adult↗
PubMedDate not supplied

[Computed tomography symptomatology of liver hemangiomas].

The paper is concerned with analysis of CT-symptomatology of 72 liver hemangiomas in 43 patients. The authors employed standard and dynamic computerized tomography. All hemangiomas were divided into 2 groups: under 6 cm and over 6 cm. Small hemangiomas were characterized by clear-cut contours and regular density. Zones of low density, regular in structure with clear-cut contours were revealed by CT in hemangiomas over 6 cm. Morphologically, this zone corresponded to a hyaline structure (a hyaline slot) making it possible to differentiate hemangiomas from necrotic tumors. In serious cases dynamic CT with visual evaluation and plotting of time-density graphs was recommended. Visually hemangioma had a picture of contrast medium accumulation, beginning from a focal periphery. Graphically the time of appearance of a contrast medium and the time of reaching a maximum for hemangiomas is delayed as compared to the same intervals of contrast medium accumulation in the liver parenchyma. It tells hemangioma graphs from graphs of other tumors, of which intervals coincide with those of liver parenchyma graphs.

Adult↗
PubMedDate not supplied

Theorems speaking for the asymmetry of all animal brains.

In random graph theory it has been proved that with the increasing size of a graph, the proportion of the non-symmetric graphs increases and this class becomes the dominant one while the number of symmetric cases turns to be 'negligible'. Thus the asymmetry (AS) is the generic property. Since nervous systems are representable by graphs or better with special digraphs, the networks, it follows that the brains are asymmetric in a strong sense according to which all cells are distinguishable from each other alone by their internal connections. Such a consequence holds perfectly only if a random evolution or generation of neural networks is supposed. Thus apparent symmetries have to come from heavily controlled (i.e. non random) ontogenetic processes. At the present time the possible total cellular heterogeneity of the various nervous systems has still unclear functional implications. In small nervous systems the odd number of neurons alone is neither a sufficient nor a necessary condition of the asymmetry in the outlined sense.

Animals↗
PubMed1989

The effect on gait of lengthening of the medial hamstrings in cerebral palsy.

The purpose of this study was to analyze the effect of lengthening of the medial hamstrings on the gait of patients who had spastic cerebral palsy. Thirty-one patients had preoperative and postoperative gait analyses. Standard parameters, such as velocity, cadence, and stride length, were evaluated, as were motion graphs of the hip, knee, and ankle. There was little difference between the preoperative and postoperative mean values for velocity, cadence, and stride length, which were expressed as percentages of normal for the patient's age. The contours of the postoperative motion graphs of the knees changed very little compared with those of the preoperative graphs; when a graph showed restricted motion preoperatively, it did so postoperatively. Although extension of the knee in stance phase improved postoperatively, the improvement was accompanied by decreased flexion of the knee during swing phase. When spasticity of both the hamstrings and the quadriceps was noted on the preoperative electromyogram, motion of the knee in the sagittal plane was markedly restricted.

Adolescent↗
PubMedDate not supplied

[Factors affecting the qualitative and quantitative composition of the acari fauna of house dust. III. Seasons].

The seasonal variations in the number of mites present in the house dust of six homes in Barcelona were studied. The samples were taken at monthly intervals between September 1972 and January 1974. Tables I and II show the total number of mites and the number of Pyroglyphidae present in each of the samples. Table III shows the monthly average of the atmospheric temperature and relative humidity (R.H.). Graphing the average of mites present in the monthly samples and comparing them to the graph of the atmospheric R.H. an almost perfect correlation of the atmospheric R.H. with the number of mites was observed (Graph 1). The statistical analysis of the results shows the existence of a highly significant correlation (alpha less than 0.001) between the average of the atmospheric R.H. of a given month and the decimal logarithm of the number of mites present in the house dust the following month (Tables IV and V; Graphs 4 and 5). The following results can be pointed out: a) The quality of mites in the house dust of Barcelona changes considerably during the year. b) The quantity is greatest during spring and autumn. c) The annual variation differs from year to year. In conclusion, it is shown that the seasonal variations in the quantity of mites present in the house dust of Barcelona are proportional to the variations in atmospheric R.H.

Acari↗
PubMed1984

Use of the hand-held calculator in office ultrasound.

Office ultrasonographers may use various fetal measurements for indices of fetal growth. One index predicts birth weight from biparietal diameter (BPD) and abdominal circumference from a set of reference tables generated by a computer-assisted analysis. An inexpensive hand-held programmable calculator may be used instead of the reference table to estimate birth weight. It produces results by direct calculation from the original equation after BPD and abdominal circumference are entered as data. A step-by-step program for a representative calculator is provided, along with data entry instructions. The program also will calculate the head-to-abdomen circumference ratio. Other functions that could be placed on pocket calculators include fetal brain-weight calculations or gestational age determinations from limb measurements. Because it is possible to represent any graph or data point set as a polynominal equation, entering the equation into a programmable calculator can eliminate tedious searches through charts and graphs. A table or graph can use only two measured parameters at a time, representing their complex relationship with a result. It is not possible to represent a result in terms of more than two parameters using a single graph or chart. A calculator permits complex calculations relating more than two parameters by the office practitioner as well as the researcher.

Anthropometry↗
PubMed1980

New approach for studying macromolecular-ligand binding. Determination of the dissociation constant for macromolecule-bound ligand by gel filtration.

A graph is presented which permits facile determination of the dissociation constant constant for a macromolecule . ligand complex from gel filtration results; it can be used without a detailed understanding of the remainder of the text. When a solution of macromolecules and radioactive ligand is subjected to gel filtrations, the amount of ligand associated with the eluted macromolecule is easily measured. This quantity is then used for obtaining the corresponding dissociation constant from the graph. Values given in the graph had been determined from an equation, which is presented in the text, by means of a program which is run on a programmable calculator (Texas Instruments SR-52). It is also demonstrated how the validity of dissociation constants so obtained can be checked independently by means of a second calculation. A modification of these procedures permits determination of the dissociation constant for those situations where there is moderate dilution of the eluted sample relative to that applied to the gel filtration column, and the graph incorporates results from such calculations. The successful application of the present approach to the determination of the dissociation constants for a tubulin . [3H]GDP complex is described. Also, the potential importance of the present approach relative to other techniques for dissociation constant determination is discussed.

Chromatography, Gel↗
PubMed1995

Viewing genome data as objects for application development.

Genomics is becoming a data-intensive science, and an increasing number of laboratories are generating data which swamps storage in traditional paper-and-ink notebooks. Capturing the data flow requires large systems with multiple applications manipulating the same or similar data. Large systems often have conflicting requirements for data representation. Consistency across applications is a prime consideration, and appropriate data representation is an important issue in developing practical systems for molecular biologists. Graphs are a natural representation for describing genome data, while objects are good for modeling the behavior necessary for laboratory applications. We present a method for translating graph descriptions of genome data into objects using objects as views on graphs. Graph representations describe genome concepts while objects capture individual views for application development insuring consistency across genome applications.

Chromosome Mapping↗
PubMed1997

Growth and growth prediction of the fibula.

Growth prediction data and graphs have not been available previously for the fibula. In this report, this information is wholly derived from a longitudinal radiographic study of growth in children. Teleradiographs of the tibia and fibula in 244 children (123 boys and 121 girls) were made at 6-month intervals from age 7 until skeletal maturity. Length measurements determined the growth of the fibula. The subjects were healthy well nourished middle class Americans, mostly of Northwest European descent. Growth occurring at the fibular growth plates was determined by the relationship to the tibia. The contribution of the proximal and distal growth plates to total length was determined by multiplying the percentage of growth occurring at each age by the longitudinal growth remaining. Graphs then were constructed using the logarithmic adjustment of Colin Moseley to produce a straight line graph. The proportion of growth occurring at the proximal and distal growth plates is not equal. More growth occurs at the proximal growth plate of the fibula than at the proximal growth plate of the tibia. The overall growth contribution of the proximal fibular growth plate is 61% compared with 57% for the proximal tibia. The graphs provided allow accurate prediction of fibular growth.

Adolescent↗
PubMed1998

[Cerebrospinal fluid proteins in the diagnosis of disorders of the blood-cerebrospinal fluid barrier in central nervous system diseases].

BACKGROUND: Many neurological diseases are connected with the dysfunction of blood-CSF barrier. The quantitative determination of CSF proteins has already been used in the diagnosis of barrier impairments and inflammatory diseases of the central nervous system. PATIENTS: Serum and CSF, totaling 264 samples, were obtained from 15 controls and 117 patients with various diseases of the nervous system. Laurell's electroimmunoassay was used for estimation of albumin and IgG levels in serum and CSF. CSF-protein profile was evaluated according to Reiber's graph for the evaluation of the CSF-protein profile. RESULTS: The graph for the protein profile can be divided into 5 functionally different parts (1--normal range, 2, 3, 4--different types of barrier dysfunctions and 5--local humoral response in CNS without any barrier impairment). There was a good correlation of CSF-protein profiles and neurological diseases in our group of patients. CONCLUSIONS: According to our results, Reiber's graph was helpful for the diagnosis of blood-CSF-barrier dysfunctions. The graph has the following advantages: a) possibility of simultaneous assessment of the functional state of blood-CSF-barrier and the inflammatory response of the CNS, b)sensitivity for the determination of pathological local IgG-production in CNS and c) minimal number of protein assays necessary.

Blood-Brain Barrier↗
PubMed2026

Pan-genomics and multi-omics for deciphering genetic variation and accelerating genetic improvement in ruminant livestock.

Livestock reference genomes have transformed the discovery of variants associated with production, reproduction, health, and environmental adaptation. Nevertheless, a single linear reference represents only one mosaic haplotype and incompletely captures sequence diversity within a species, particularly structural variants, copy-number changes, repeat-rich regions, and breed-specific sequences. Pangenomes address this limitation by integrating multiple high-quality assemblies or population-scale variants into a unified sequence or graph representation. Concurrently, multi-omics approaches connect genomic variation with transcriptomic, epigenomic, manuscriptproteomic, metabolomic, and microbiome responses, thereby improving biological interpretation of genotype-phenotype relationships. This review synthesizes recent progress in livestock pangenomics and multi-omics, with emphasis on cattle, goats, sheep, water buffalo, and chickens. It describes advances in long-read and haplotype-resolved sequencing, graph construction, structural-variant discovery and genotyping, functional annotation, and integrative analysis. Recent pangenome studies have uncovered substantial non-reference sequence, reduced reference bias, identified breed- and population-specific structural variants, and resolved candidate variants underlying pigmentation, body size, tail morphology, cashmere production, altitude adaptation, and other economically relevant traits. However, translation into routine breeding remains constrained by uneven population representation, inconsistent structural-variant definitions, limited functional annotation, computational demands, and insufficient validation across environments. Future progress will depend on diverse near-complete assemblies, graph-aware imputation and genomic prediction, long-read transcriptomics, single-cell and spatial omics, rigorous causal validation, and open, interoperable resources. Together, these developments can support more accurate, resilient, and biologically informed livestock improvement. Importantly, current dairy-cattle evidence indicates that pangenome-derived structural variants can substantially improve variant discovery and functional interpretation while yielding only marginal average gains in routine genomic prediction, favoring targeted augmentation rather than wholesale replacement of established SNP-based evaluations.

Animals↗
PubMedDate not supplied

Ultrasound fetal biometry charts for a North American Caucasian population.

PURPOSE: This study was done to produce enhanced fetal biometry charts and graphs presenting percentile values as a function of fetal age. METHODS: The relationships between the ultrasound measurements of 10 fetal parameters and menstrual age were determined by a cross-sectional study. Data were obtained from 508 to 790 fetuses. Anatomic structures were scanned and measured 3 times during 1 routine sonographic examination. The study group consisted of 1,396 Caucasian women who had normal singleton fetuses with confirmation of menstrual dates by sonography before 14 weeks and for whom complete pregnancy outcome information was available. For each of the 10 parameters, percentile curves were derived for the 5th, 10th, 25th, 50th, 75th, 90th, and 95th percentiles. RESULTS: Ready-to-use fetal measurement charts and graphs are presented in a format giving the percentile values as a function of fetal age. There were no significant differences between male and female fetuses. CONCLUSIONS: These fetal biometry charts and graphs, obtained from a North American Caucasian population, enhance previously published data.

Abdomen↗
PubMed1997

Biologically effective doses in medium dose rate brachytherapy of cancer of the cervix.

The amount of dose reduction on changing from low dose rate (LDR) brachytherapy to medium dose rate (MDR) or high dose rate (HDR) afterloading has been the subject of much debate. The magnitude of reduction depends, together with other possible factors, on two radiobiological parameters: the alpha/beta ratio and the half-time of repair of the relevant tissues. In an attempt to extract these radiobiological parameters for the late rectal complications observed in our previously published clinical results four different schedules using MDR and one using LDR are analyzed. The percentage incidence of complications was a function of increasing biologically effective dose (BED), but would yield nonsense scattergrams if plotted against raw total dose. In addition, for three other published MDR series, three LDR series, and two HDR series, the incidence of rectal complications is plotted against BED to examine the predictive potential of using BED as the surrogate of total dose. Our own results were published in 1996, consisting of 102 patients treated at the LDR of 0.44 Gy/hr and 88 patients treated by four different schedules using an MDR of 1.6-1.7 Gy/hr. Follow-up is at least 3 years in all schedules. The linear quadratic formula including the "g" dose rate factor was used to analyze them, assuming exponential repair of the repairable beta term. First, multivariate and profile likelihood analyses were carried out to obtain estimates of alpha/beta and T1/2 for rectal late responding tissues. Then graphs of incidence of rectal complications vs. BED were constructed, assuming alpha/beta = 3 Gy and T1/2 = 1.5 hr, values which had not been contradicted by the multivariate analysis. Graphs were drawn both for "all grades including mild reactions" (grades 1 + 2 + 3) and for "serious" complications (grade 3 in our system). In addition, other published cervical brachytherapy series were reviewed, with calculation of their BEDs if not published by the authors. It was necessary to review and compare their grading systems, so that "mild and moderate" (grades 1 and 2) could be contrasted with "serious" (grades 3 and 4 or 5 in various systems). Comparisons were made with other published results, including three LDR, three MDR, and two HDR series spanning from 1982 to 1997. The BEDs at which the incidence of rectal complications rose above the arbitrary level of 10% were compared for all three ranges of dose rate. The multivariate analysis gave estimates of alpha/beta and T1/2 which were not significantly different from 3 Gy and 1.5 hr, respectively, so these values were used to compute the BEDs for the subsequent comparisons. It was found that the graphs of incidence of rectal complications for "all grades including mild" agreed rather better between all series than might have been expected, within a provisional (10%) threshold BED of range 100-123 Gy3 (60-74 Gy given as 2 Gy fractionated external beam or as LDR). The dose-response curves diverged above these values, as expected until common grading systems such as SOMA/ LENT become more widely used. For "serious" complications the 10% incidence occurred at a median BED of 140 Gy3 (84 Gy given as 2 Gy fractionated external beam or as LDR), range 124-155 Gy3. The use of BED (or extrapolated response dose), assuming alpha/beta = 3 Gy and T1/2 = 1.5 hr, instead of total dose, enabled incidence of late rectal complications in cervical brachytherapy with LDR, MDR, and HDR to be plotted in a reasonably consistent way. This does not mean that those parameter values have been definitively determined, but they appear to be provisional values that may be of use in comparing the expected effects of new schedules until better values are obtained from greater use of common grading systems.

Brachytherapy↗
PubMed1999

Radial force of coronary stents: a comparative analysis.

High radial force has become an essential feature of new coronary stents. These stents are expected to exhibit sufficient radial force and minimum radial recoil when deployed in atheromatous lesions of various morphologies. The aim of this study was to compare the radial force of 17 coronary stents in vitro (Anglodynamics, ACS Multilink, AVE Micro II and GFX, Bard XT, Biocompatibles PC, Cook GR II, Cordis Crossflex, Hexacath Freedom, Johnson & Johnson PS 153'PS 154, and Crown, Medtronic Wiktor and BeStent BEL-15, Saint-Come SC 1616, Scimed Nir 7 and 9). Two in vitro mechanical tests were performed to assess the stent radial force. The first test measured the deformation of coronary stents in a V-stand by using a deformation controlled by a dynamometer based on a longitudinal generatrix. The precision was of 1 micron. This comparative test highlighted the appreciable variation in behavior of the range of tested stents in terms of resistance to local compression. The line graphs obtained show a very small (and in some cases nonexistent) purely elastic behavior area in the stents, with this result reflecting a small (<0.4 Newtons) range of forces applied to all stents. Above this value, the stents did not return to their size before compression and the line graph remains approximately linear for a long period. It was therefore possible to distinguish between two families of stents on the basis of the presence or absence of this elastic area. In the second test, the stent was deployed in a 3.0-mm elastic tube and a pressure gradient created between the interior and exterior of the tube. The precision was of 50 microns. A typical line graph of the pressure-diameter relationship was recognizable for a given stent. No difference in behavior between the different coronary stents was noted up to 0.3 x 10(5) Pa; subsequently, after 0.3 x 10(5) Pa, sizable deformation differences were visible between the least resistant stent, the BeStent BEL-15, and the most resistant stent, the Crossflex.

Evaluation Studies as Topic↗
PubMed1987

Determination of the urinary cortisol production rate using (1,2,3,4-13C)cortisol. Isotope dilution analyses at very small enrichments.

An isotope dilution mass spectrometric method to determine the urinary cortisol production rate (CPR) in babies and children is described. The method uses stable isotopically labelled (1,2,3,4-13C)cortisol. The tracer is intravenously administered to the patient and urine is collected for the following three days. Following extraction, enzymic hydrolysis, purification and isolation by high-performance liquid chromatography (HPLC) the urinary cortisol metabolites tetrahydrocortisone, tetrahydrocortisol, alpha- and beta-cortolone are separately oxidized the common product, 11-oxo-aetiocholanolone. The methyl oxime tert-butyldimethylsilyl ether derivative (MO TBDMS) was analysed by gas chromatography mass spectrometry. Quantification of the isotope enrichment was carried out by unlabelled, and at m/z 348 for labelled 11-oxo-aetiocholanolone. HPLC isolation of the metabolites together with the oxidation step allowed very small isotope enrichments, sometimes down to 0.1% (1:1000), to be reliably measured against a linear calibration graph containing 0 to 1% (13C4) enrichments. The standards for the calibration graph were synthesized from mixtures of labelled (13C4) cortisol and natural cortisol, and the calibration graph was prepared each time samples were measured. The long term instrumental precision of the isotope dilution analyses was 0.91% for a derivatized sample containing a (13C4) enrichment of 0.5% (measured on six different days over seven months). The coefficient of variation of the complete procedure for the four cortisol metabolites was between 1.17 and 2.14%. The clinical applicability of the method is demonstrated by presenting the results of a CPR determination in a patient.

Adolescent↗