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At least 19 recordsLinked to original sources
PubMed1979

[Computer tomographic demonstration of lymph node metastases from malignant testicular tumours. A comparison of lymphography and computer tomography (author's transl)].

Lymphography and computer tomography was performed on 64 patients with malignant testicular tumours in order to demonstrate lymph node metastases. In 60 patients it was possible to confirm the findings by surgery. In 43 patients there was agreement between the findings of the computer tomogram and the lymphogram. In 39 of these patients lymph node metastases had been demonstrated, in three there was a false negative and in one a false positive. Amongst the patients in whom there was a descrepancy between the two types of examination, the CT findings were confirmed histologically in twelve, and the lymphographic findings in nine. In 12.5% CT added significant additional information. Accuracy of lymphography was 73% and of computer tomography 80%. Specificity for each examination was 79%.

Adult↗
PubMedDate not supplied

Computational analysis and dosimetric evaluation of a commercial irregular-fields computer program.

The proper evaluation of the accuracy of a new computer program for radiation-therapy dosimetry requires consideration of both the mathematical algorithm used in the program and the performance required in clinical applications. As an example, our evaluation of the irregular-fields dosimetry program currently marketed by SHM for their Rad-8 system is described. The evaluation begins with an explanation of the mathematical computation described. The evaluation begins with an explanation of the mathematical computation method, with emphasis on the points where the calculation differs from previous methods. Next, the procedure for setting up the beam data file is discussed. Finally, a step-by-step procedure is described in which calculated doses are compared with measured doses, using a Varian Clinac-4 with lead flattening filter, and the limits within which a +/- 5% accuracy is attainable are estimated. Some sources of error and areas for possible improvements are mentioned.

Computers↗
PubMed1977

[Continuous automatic ECG analysis using a computer with the cardiac signal directly led in from the patient (II). The diagnosis of heart rhythm disorders using a computer].

It is shown that appraisal and comparison of the duration of the R-R intervals in continuous surveillance of patients by means of electronic computers on the on-line regimen provides for automatic diagnosis of most types of disorders of the cardiac rhythm. The elaborated criterion of arrhythmic cardiac contraction (ACR-R), which takes into account not only the absolute value of the time between heart contractions but also the trend of the changes in the next R-R interval, provides a high percentage of revealed arrhythmic contractions. Disorders of the rate of cardiac contractions may be diagnosed by means of an electronic computer by comparison between the mean value of intervals of normal duration and the preset threshold values. Disorders of the rhythm may be diagnosed by means of an electronic computer by assessment and comparison of the arrangement of the combinations of short, normal, and long R-R intervals. The elaborated algorithms are described in detail and the block diagrams of the programs are shown.

Arrhythmia, Sinus↗
PubMed1978

[Fast computer tomography for investigation of the heart--"computer cardiotomography". Methods and early results (author's transl)].

The early results in the investigation of normal and pathological hearts using fast computer tomography are presented. By means of tomographic sections of cadaver hearts, it has been shown that it is possible to distinguish the ventricular cavities and individual cardiac walls by this non-invasive method. Changes in volume of the ventricles and atria due to various forms of stress are easily distinguishable. Myocardial scars can be distinguished from other circumscribed myocardial defects. The particular advantages of this method, which is non-invasive, painless and easily repeatable, do not need to be stressed. The technique adds a significant dimension to previously available non-invasive diagnostic methods, such as ultrasound echo-cardiography.

Aortic Valve↗
PubMed1979

Computed tomographic cavo-urography: lower-extremity contrast infusion simultaneous with computed tomography of the retroperitoneum.

Successful opacification and distention of the inferior vena cava was obtained simultaneously with computed tomography by contrast infusion through a lower-extremity vein. Images obtained by this method displayed retroperitoneal anatomical relationships to better advantage, permitting more accurate interpretation of the upper retroperitoneum, particularly in lymphoma.

Contrast Media↗
PubMed1979

[Society of Nephrology, Computer Technology Commission. Dialysis computer program. VI. - Survival and risk factors].

The sixth report of the "Diaphane Dialyse Informatique" Program concerns 2,518 adult patients (age 15 and over) treated by chronic hemodialysis or hemofiltration in 33 French dialysis centres between June 1972 and December 1978. 1) The number of centers participating to the program is progressively increasing. Overall duration of follow-up represents 4,192 patient-years, allowing precise evolutive studies of terminal renal failure treated by hemodialysis. 2) Mean age at start of treatment continues to increase. Among 709 patients who started treatment in 1977-1978, 8,8 p. 100 of men and 11 p. 100 of women were over 69 years old. 3) Patients with diabetic nephropathy represent 4,4 p. 100 of all patients dialyzed between 1972 and 1978 and 5,9 p. 100 of the patients starting treatment in 1977-1978. 4) The percentage of patients temporarily treated by peritoneal dialysis before hemodialysis decreases from 32,9 p. 100 in 1973-1974 to 15,9 p. 100 in 1977-1978. 5) In 1978, 65,3 p. 100 of patients are dialyzed 3 times a week with a mean weekly duration of 14,0 h for male and 12,9 for female. 73 p. 100 of the patients are dialyzed during the night. 6) Disposable parallel plate hemodialyzers (71,8 per cent of dialysis sessions in 1978) and hollow fiber hemodialyzers (11,6 per cent) progressively replace disposable coil dialyzers and non disposable Kiil dialyzers. 7) Transient hypotensive episodes during dialysis sessions remain the most frequent complications (21,7 per cent of sessions in 1978). Transient hypotensive episodes are more frequently observed with coils than with parallel plate hemodialyzers or with hollow fiber dialyzers. 8) Mean diastolic blood pressure (DBP) +/- SD is 101,9 +/- 21,7 mmHg at start of dialysis and 81,4 +/- 11,8 mmHg when dialysed. During the course of treatment 28,7 per cent of the patients receive long term antihypertensive treatment. In spite of dialysis and antihypertensive treatments 11 per cent of all patients followed up maintain DBP greater than or equal to 95 mmHg. 9) Viral hepatitis remain the most prominent infectious problem with 30 per cent of patients being chronic Hbs antigen carriers. 10) Annual death rate calculated in the 2,518 patients dialyzed between 1972 and 1978 (78/1000) is 12 times superior to the death rate of the French population, adjusted for sex and age to the dialysis population. 43,1 per cent of deaths are of cardiovascular origin. Risk factors for overall mortality are age, sex (male), existence of a vascular or diabetic nephropathy, twice weekly dialysis strategy, elevation of systolic or diastolic blood pressure during the course of dialysis treatment, hypocholesterolemia and to a lesser extent hypotriglyceridemia. On the contrary, hypercholesterolemia, hypertriglyceridemia and hyperuricemia do not appear as risk factors for overall mortality or cardiovascular mortality. These results plead for a perfect control of hypertension and to the extension of thrice weekly dialysis for the whole population of patients treated by maintenance hemodialysis.

Adolescent↗
PubMed1976

Computer recognition of generalized spike-wave discharges.

Twelve 12h daytime telemetered EEGs were read for generalized spike-wave (S-W) bursts by a computer and independently by three experienced electroencephalographers. The computer system was a hybrid of analog devices (tape-recorder, voltage summator, and high-pass filters) and a multipurpose laboratory digital device (PDP-12). The computer was programmed to identify only the location on the record and the duration of the generalized S-W paroxysms. From 1,462 discharges identified by both the readers and the computer, a consensus list of 609 was derived by selecting only those bursts identified by all three readers. The computer recognized 516 (85%) of those bursts on the consensus list; the computer's accuracy, as compared with the consensus, rose to 92% when portions of the EEG containing sleep were discounted. The computer also recognized as generalized S-W paroxysms 15 high-voltage transients, which none of the three readers selected. Ten of these, however, occurred during sleep. When the computer results were added to those of the three readers to permit a four-way inter-reader comparison, the computer was found to have had about as many isolated decisions as any of the three readers. In the number of bursts recognized, the computer tended to be about as conservative as the reader under whose guidance it was originally programmed. The computer's accuracy in measuring burst duration was not evaluated statistically.

Computers, Hybrid↗
PubMed2025

Catalyzing computational biology research at an academic institute through an interest network.

Biology has been transformed by the rapid development of computing and the concurrent rise of data-rich approaches such as, omics or high-resolution imaging. However, there is a persistent computational skills gap in the biomedical research workforce. Inherent limitations of classroom teaching and institutional core support highlight the need for accessible ways for researchers to explore developments in computational biology. An analysis of the Scripps Research Genomics Core revealed increases in the total number and diversity of experiments: the share of experiments other than bulk RNA- or DNA-sequencing increased from 34% to 60% within 10 years, requiring more tailored computational analyses. These challenges were tackled by forming a volunteer-led affinity group of approximately 300 academic biomedical researchers interested in computational biology, referred to as the Computational Biology and Bioinformatics (CBB) affinity group. This adaptive group has provided continuing education and networking opportunities through seminars, workshops, and coding sessions while evolving along with the needs of its members. A survey of CBB's impact confirmed the group's events increased the members' exposure to computational biology educational and research events (79% respondents) and networking opportunities (61% respondents). Thus, volunteer-led affinity groups may be a viable complement to traditional institutional resources for enhancing the application of computing in biomedical research.

Computational Biology↗