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Calculation of received dose intensity for combinations of drugs using small-cell lung carcinoma treatment regimens as examples.

Programs are presented for the calculation of received dose intensity in combination chemotherapy regimens. These provide methods for determining the final dose intensity, the mean cumulative dose intensity together with its standard error, and other tabular and graphic summaries. Two ways of dividing patients into high and low received-dose-intensity groups are proposed. Methods are illustrated using data from Mid-Atlantic Oncology Program (MAOP) 2183, a phase III evaluation of a six-drug alternating combination vs a three-drug "standard" combination treatment for extensive small-cell lung cancer. Comparisons of received dose intensity with demographic and outcome variables are presented.

Antineoplastic Combined Chemotherapy Protocols

The determination of the absolute bioavailability for drug substances with long elimination half-lives (with PC-programs for the method of truncated areas).

A survey is given of the methods for the determination of the absolute bioavailability for drug substances with long elimination half-lives. All methods depend on the assumption of linear pharmacokinetics. Emphasis is laid on Urso and Aarons' regression method of truncated areas-under-the-curve (AUC) to obtain estimates of the absolute bioavailability, F, and the absorption rate constant, ka, without obeying the otherwise general rule of following blood or plasma levels for at least three times the terminal half-life. It is shown by simulation when the linear and when the logarithmic trapezoidal rule is to be used for the calculation of the AUC. Two PC-programs for the regression method of truncated areas are presented: one program (SIMF&KA.EXE) simulates, based on tentative pharmacokinetic parameters, whether a blood sampling scheme, together with the precision of the analytical assay, is adequate to obtain accurate and precise estimates of F and ka; the method is insensitive to large variations in the tentative value of the elimination half-life. The other program (ESTF&KA.EXE) provides estimates of F and ka, with standard deviations of the estimates, from empirical data.

Biological Availability

An automatic system for chromosomal analysis applied to prenatal diagnosis.

Computer-assisted metaphase analysis for prenatal diagnosis can be economically performed by a preexisting hardware-software system. The program can be run by technician-level (i.e. nonspecialist) personnel who can opt for the automatic operational mode for good quality metaphases or for the semimanual mode for problem metaphases (numerous superpositions, artifacts, etc.). The karyotype can be obtained in conversational mode. Hardcopy output is available for all modes.

Chromosomes

Computer-aided determination of haemodynamic properties of human heart from cine left ventriculography.

The silhouettes of the left ventricle seen on a cine ventriculogram were used as the graphic input to a pattern analysis programme. The programme measured the coordinates of points around silhouette. It selected the longest chord within the perimeter and determined its length, the area within the perimeter, and the volume of the resulting ellipsoid of revolution. The output from the programme was a global clinical report which included scaled reproductions of the silhouettes, maximum and minimum ventricular volumes, the stroke volume, and the ejection fraction. Local analysis consists in comparison of the contraction profile for the specific patient with the mean pattern obtained from a control group of 24 patients with no myocardial pathology. The graphical and numerical results help in following the progress of disease, in choosing candidates for coronary artery bypass, and in evaluating the results of medical or surgical treatment.

Cineradiography

Survival prediction for clear cell renal cell carcinoma based on deep multimodal synergistic survival network.

Objective.To propose a deep multimodal synergistic survival analysis framework (Deep Multimodal Synergistic Survival Network, DMSSN) to achieve accurate prognostic analysis for clear cell renal cell carcinoma (ccRCC).Methods.This study (DMSSN) utilized matched multimodal data from the Cancer Genome Atlas-KIRC database, including CT imaging data, whole slide images, copy number variation (CNV) features, and clinical data. Deep Canonical Correlation Analysis was employed to map heterogeneous modalities into a shared latent space. Contrastive learning was introduced to enhance semantic consistency across multimodal features, and a gating network was utilized for the adaptive fusion of multimodal information to achieve precise survival risk prediction for patients.Results.Experimental results demonstrated that DMSSN achieved a Concordance Index (C-index) of 0.8153 ± 0.0994, with a Log-rank testp-value of 1.6553×10-11. DMSSN exhibited significant performance advantages over traditional statistical methods like Log-rank-Cox (0.7055 ± 0.0670) and machine learning methods such as Random Survival Forest (RSF) (0.6836 ± 0.1048). Furthermore, in comparison with similar deep learning approaches, DMSSN outperformed late fusion strategies (0.7493 ± 0.1211) and discrete-time survival models such as DeepHit (0.7655 ± 0.1041) and Nnet-surv (0.7694 ± 0.0635). Notably, DMSSN still achieved the best predictive performance when compared to the classic deep survival model DeepSurv (0.7919 ± 0.0978) and advanced state-of-the-art multimodal fusion frameworks like Context-Aware Transformer (0.7735 ± 0.0818) and Multimodal Co-Attention Transformer (0.8102 ± 0.0972). Ablation studies showed that removing any single modality led to a decline in performance, with the largest numerical decrease occurring after removing CT imaging features (C-index decreased to 0.7327), validating the complementarity of multimodal data and the pivotal role of radiomic features in prognostic assessment. Module ablation experiments further confirmed the effectiveness of the core components.Conclusion:By effectively integrating imaging, pathology, genomic, and clinical features, the DMSSN framework demonstrates superior performance and robustness in the survival prediction of ccRCC.

Carcinoma, Renal Cell

Kanner's syndrome or early-onset psychosis: a taxonomic analysis of 142 cases.

Case history data on 142 psychotic children were obtained using the Rimland Diagnostic Check List. A particular variety of the method known as numerical taxonomy was used to classify the children into subgroups on the basis of responses on the Check List. A comparison was made between a classification of Kanner's syndrome vs. "no Kanner's syndrome" and a classification using random classes as starting points. The "best" classification of the data was one in which 2 classes were obtained, one containing all the Kanner's syndrome children plus other early-onset, nonrelating psychotic children and the other containing children with later onset and more varied symptoms. Those attributes which significantly differentiated between the classes both in the "best" classification and in the Kanner's syndrome classification were extracted. A distinction between Kanner children and other similar children was found only for 3 specific behaviors: obsessive desire for sameness, islets of special ability, and skillful manipulation of small objects.

Adolescent

A neuromuscular monitoring system based on a personal computer.

We have developed a computerized neuromuscular monitoring system (NMMS) using commercially available subsystems, i.e., computer equipment, clinical nerve stimulator, force transducer, and strip-chart recorder. This NMMS was developed for acquisition and analysis of data for research and teaching purposes. Computer analysis of the muscle response to stimulation allows graphic and numeric presentation of the twitch response and calculated ratios. Since the system can store and recall data, research data can be accessed for analysis and graphic presentation. An IBM PC/AT computer is used as the central controller and data processor. The computer controls timing of the nerve stimulator output, initiates data acquisition, and adjusts the paper speed of the strip chart recorder. The data processing functions include establishing control response values (when no neuromuscular blockade is present), displaying force versus time and calculated data graphically and numerically, and storing these data for further analysis. The general purpose nature of the computer and strip chart recording equipment allow modification of the system primarily by changes in software. For example, new patterns of nerve stimulation, such as the posttetanic count, can be programmed into the computer system along with appropriate data display and analysis routines. The NMMS has functioned well in the operating room environment. We have had no episodes of electrocautery interference with the computer functions. The automated features have enhanced the utility of the NMMS.(ABSTRACT TRUNCATED AT 250 WORDS)

Computer Systems

[Evaluating the independence of paraplegic patients at the end of the first rehabilitation--a multicenter project of computer-assisted quality control in rehabilitation].

Rehabilitation of patients who became handicapped due to illness or trauma is a difficult process, involving many therapeutic sections. The necessity to document the results of different rehabilitation programs led to the development of numerous scoring systems in the USA within the last 25 years, considering mainly functional results. The present functional assessment score (DMGP-Selbständigkeitserfassung für Tetraplegiker) for the documentation of self-sufficiency in tetraplegic patients after primary rehabilitation has been designed to record the quality of rehabilitation programs and has been exclusively designed for patients with quadriplegia, it there fore has the advantage of a better and more precise documentation over other general functional scoring systems, especially for the interests of different sections (occupational therapy, physiotherapy) being involved in this special rehabilitation program. The aim of the documentation is to record the degree of independence of tetraplegic patients after primary rehabilitation, considering the individual requirements of aids and the assumption of circumstances suitable for wheel-chairs. Since all data are collected on a computer-readable form each participating clinic has the opportunity for an individual analysis of the own results, as well as the opportunity of comparing it with the collective results.

Activities of Daily Living

Quantitation of rodent catalepsy by a computer-imaging technique.

Catalepsy is usually defined as a behavioral state in which an animal maintains an unnatural posture for an extended period of time. While numerous laboratory models have been developed for assessing catalepsy, a common problem encountered with most procedures is the difficulty in quantitating immobility. Measurement of catalepsy is still frequently subjective in nature. To eliminate this subjectivity, a computer-based technique was developed for quantitating catalepsy in mice and rats as measured on the elevated ring. The system consisted of a video camera that was focused on either three mice or two rats. Their behavior was recorded during a 5-min session on videotape that was subsequently transmitted to a Macintosh II microcomputer via a Scion Image-Capture 2 board. A modification of the NIH Image 1.17 public domain program allowed the image of the rat to be transformed to a purely black or white image by assigning pixel values of either 0 or 256. The subsequent captured image was preprocessed in an identical manner and each pixel was subtracted from its corresponding pixel in the previous frame. Thus, changes in animal posture between the two frames can be quantitated. One subtraction cycle (acquisition, bilevel processing, and subtraction) was repeated at an average rate of approximately one per second. To quantitate immobility by image analysis, each frame was subtracted from the previous frame during a 5-min session. The resulting data were sorted according to the magnitude of movement (number of changed pixels) and plotted vs. time.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals

Automated, rapid identification of bacteria by pattern analysis of growth inhibition profiles obtained with Autobac 1.

A scheme for identifying bacteria has been devised which utilizes the inhibition patterns obtained by Autobac 1 with routine and unusual antimicrobial agents and with other differentially inhibitory chemical compounds. Over 600 compounds were initially identified from the literature, and over 125 of these were selected for further testing on the basis of antibacterial activity most conducive to the instrument-generated differential scheme. Numerical growth index information derived by light scatter comparisons from the instrument were analyzed by computer, utilizing the quadratic discriminant function statistical technique. In comparison with conventional methods, accuracy for the 10 bacterial genera studied was 95% or greater. Results indicate a potential for both bacterial identification and antimicrobial agent susceptibility testing in the clinical laboratory within 3 to 5 h when using this automated approach.

Acinetobacter

Results of computer-aided diagnosis of peripheral bronchial carcinoma.

Radiographic images can be converted into numerical sequences that can be evalueate by computer to determine the significance of certain radiographic findings in peripheral pulmonary nodules. Of three methods (discriminant analysis. Bayes' theoroem, and the Calm system), discriminant analysis has proven the best with an accuracy rate of 85%. By taking into account serial radiographs and statements on the possible growth of the neoplasm, the accuracy of the method can be increased to 90%. A simplified, inexpensive and effective method for application of this diagnostic tool is described.

Adult

Computer analysis of defined populations of lymphocytes irradiated in vitro. II. Analysis of thymus-dependent versus bone marrow-dependent cells.

Three uniform populations of T and B cells exposed to varying amounts of x-irradiation are examined utilizing computer-assisted morphometric analysis. These populations are: thoracic duct lymphocytes (TDL) from congenitally athymic (nude) mice (B cells); TDL from CBA mice treated with anti-Ig plus complement (T cells); and computer-selected untreated T cells from CBA TDL. Irradiated B cells show a more even dispersion of the nuclear chromatin and a dose-dependent increase in relative nuclear area beginning with the lowest dose evaluated (50 rads); no significan change in total optical density (OD) is demonstrable over the dose range evaluated (0 to 2000 rads). Anti-Ig-treated irradiated T cells demonstrate an initial shift toward lower OD values as a function of dose followed by a marked rise of OD values at 2000 rads, where numerous densely staining Feulgen-positive aggregates are identified. The relative nuclear area of this cell population also shows a biphasic response to radiation injury with an initial increase at the lower dose levels followed by a progressive decline to approximate control levels at 2000 rads. This effect is mirrored by the alteration in total OD which, after a decrease at low dose levels, approximates control values at 2000 rads. The computer-selected T cells show little change in OD values at the low-dose levels but show a marked increase in the more densely staining Feulgen-positive material following 2000 rads. This population reveals no apparent change in either relative nuclear area or total OD as a function of dose. Thus, untreated computer-selected T cells exhibit remarkably little evidence, morphologically, of radiation injury of doses associated with pronounced alterations on the part of B cells. In addition, treatment of a mixed cell population (CBA TDL) with anti-Ig plus complement to remove the B cells appears to alter the response of the residual T cells to radiation injury. These results, in conjunction with recent evidence to support the concept that T cells possess surface Ig, suggest that an Ig-anti-Ig interaction may alter the radiosensitivity of T cells.

Animals

Enlarged acid-base and blood gas calculations by electronical data computing in the blood gas laboratory.

A rapid anaysis of parameters of the acid-base equilibrium and blood gases during open heart surgery and emergency therapy is absolutely necessary. Computing of the several parameters of the acid-base status by slide rules or nomograms is time consuming and can be shortened by computer applications. The central blood gas laboratory consists of a blood gas analyzer for PO2, PCO2 and pH, an electronic desktop calculator, a four color X-Y-plotter and two data lines to the cardiac surgery unit and to the intensive care unit. The time needed for computing and feedback of the parameters could be decreased to one quarter. In addition to numerical data printout, a graphical representation of the several parameters is possible on a X-Y-plotter and includes the Rahn-Fenn-O2-CO2-Diagram with venous admixture, ventilation perfusion ratio, alveolar dead space ventilation and the standard and actual oxygen dissociation curve as well as the pH/HCO3- Acid-Base nomogram. Furthermore, a computer diagnosis of the actual disturbances can be plotted.

Acid-Base Equilibrium

[Multivariant discriminance analytical computation methods for the evaluation of clinico-chemical parameters in liver and biliary tract diseases].

Multivariate variance and discriminance-analytic investigations on the value of evidence of clinico-chemical tests in the diagnostics of diseases of the liver and the biliary tract gave the following results: 1. By means of clinico-chemical methods and discriminance-analytic functions we succeed in 50% of the cases in formulating a correct diagnosis, in more than 75% of the cases a correct probability diagnosis (3 first places in the rank of diagnoses). Sensitivity and specificity of discrimination were established for 15 classes of diagnoses. 2. Due to the intercorrelations of test results biochemical maximum programmes contain numerous redundant parameters measured on diagnostic information values. With the help of a test for indispensability (redundance test) among 20 parameters owy 5-6 were characterized as indispensable. An optimal combination of parameters should not transgress an extent of 14 tests. 3. Results of reclassifications with discriminance analytic functions confirmed that the discriminance analysis is an extraordinarily suitable method for the computer-supported finding of a decision, on which basis aimed additional investigations might be performed.

Analysis of Variance

[Nystagmus analysis by computer (author's transl)].

Automatic quantitative nystagmus analysis by means of a digital computer primarily gives a lot of data. Analysis then means reducing this amount of numerical data to a few relevant results. Because the diagnostic importance is not known yet for all available nystagmus parameters, this implies the risk of losing essential informations. Therefore, limitations of the number of parameters as well as of the duration of the investigated intervals by the method of analysis have to be avoided. This then allows studying the diagnostic value of new parameters (e.g. of the fast components) or the time course of reaction intensity. From this point of view a method of quantitative nystagmus analysis is described.

Computers

[Objectivation of tremor and motion disorders via computerisation (author's transl)].

The quantitative analysis of motion disorders of the upper extremities can be performed by means of a joystick connected with a minicomputer. Therefore a random squarewave curve is drawn on a computer display and the patient must follow it with the joystick. The deviation of the two curves are recorded, analysed and documented numerically and graphically.

Diagnosis, Computer-Assisted