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At least 19 recordsLinked to original sources
PubMed1990

Operation in hip fracture patients--analysis of the time factor.

The time that elapsed between the fracture, arrival at the hospital and subsequent surgery was studied retrospectively in 274 hip fracture patients. In 8.8 per cent of the patients the time of fracture could not be established. In 14.6 per cent there was delay before arrival at the hospital. Operative delay for medical conditions occurred in 6.6 per cent. When these groups were excluded, there was no difference in the mortality or hospital stay between patients from their own homes or old people's homes who had immediate surgery (within 8 h of arrival) and those in whom surgery was delayed for up to 48 h.

Aged↗
PubMed1976

[Time factors factors in radiotherapy. Introduction (author's transl)].

The role of time factors, the fractioning and spread of irradiation, continue to occupy an important place in conference, symposia and meeting of radiotherapists and our own Society has followed this tradition by devoting to the subject this session of the Journées de Radiologie 1975. The problem is a constant feature of everyday clinical practise. Whilst the majority of radiotherapists are prudently attached to the traditional method of 5 sessions per week, they are frequently forced to change this rhythm for pathological reasons, the personal convenience of the patient or problems with apparatus. The association of transcutaneous and curietherapeutic irradiation adds new parameters : the rate of the curie-therapy, the relative contribution of the 2 methods of irradiation, their sequence and the interval which separates them. Poor results of radiotherapy in certain situations indicates the possible value of determining whether other methods of the distribution per session and in time might lead to an improvement. Under these numerous circumstances, one is led to compare different forms of irradiation and to assess their possible biological differences. Objective description of the type of irradiation may be limited to the contents of the treatment sheet. However this does not easily express the biological quantity of the irradiation. As soon as the differences between two types of irradiation involves two parameters, they can no longer be effectively compared. The usefulness of a single figure to express the biological value of irradiation is obvious. With this aim, Cohen proposes calculation of levels of cell survival resulting from irradiation and extracts the parameters of this calculation from clinical results published in the literature. By similar analysis, Ellis has deduced the overall role of time factors which is expressed by the simple relation of the N.S.D., which has itself been at the origin of other expressions seeking to be more convenient and universal. Thus various solutions to the problem are available to radiotherapists. However a wide degree of disagreement exists between them, increasing with differences between the forms of irradiation...

Humans↗
PubMed1988

Benzodiazepine dependence--aetiological factors, time course, consequences and withdrawal symptomatology: a study of five cases.

The development and time course of benzodiazepine (BZD) dependence is reported for five case histories. The underlying psychiatric disorders, life-events as potential initiators of BZD use/abuse and psychosocial consequences are discussed. The abstinence symptoms appearing during a course of standardized withdrawal therapy are described in detail. The case reports clearly demonstrate the chronic nature of the development of BZD dependence and of the tendency to increase the dosage which may occur only after years of intake and the gradual appearance of negative effects of chronic BZD intake.

Adult↗
PubMed1977

[Time factor in local radiotherapy (author's transl)].

This study was aimed at determining the influence of time factor in local radiotherapy in patients with spindle cell neoplasms of the skin or basal cell carcinomas of the face, treatable in a single plane. These neoplasma were treated using identical doses (6,000 rads distributed over the envelope isodose), but divided at random into two groups corresponsing to two different spreads (60 +/- 12 hours and 156 +/- 12 hours). The biological effects observed (rate of disappearance of the lesion, intensity of skin reaction, duration of skin reaction) showed no difference between the two types of treatment. This results is unexpected considering the important influence of time factor in the case of fractionated irradiation. In fact, if it is accepted that between 60 and 156 hours, cellular multiplication phenomena are equivalent to approximately 30 rads per day, the difference in spread the two types of treatment is not sufficient to give a significant result.

Basal Cell Carcinoma↗
PubMed1990

Trend surface models in the representation and analysis of time factors in cancer mortality.

A method of graphic representation of time factors in cancer mortality is presented, based on different tonalities of grey applied to the surface of the matrix defined by various age-specific rates. It is illustrated using mortality data from cancers of the mouth or pharynx, oesophagus, larynx and lung in Italian and Swiss males. Progressively more complex regression surface equations are defined, on the basis of two independent variables (age and cohort) and a dependent one (each age-specific rate). General patterns of trends were thus identified, showing important similarities in cohort and period effects, but also noticeable differences in time-related factors in mortality from various neoplasms of the upper digestive and respiratory tract. For instance, there were declines in mortality from cancers of the mouth or pharynx in the oldest age groups, whereas rates were appreciably upwards at younger and middle age, particularly in Italy. Likewise, cancers of the oesophagus and, chiefly, of the larynx were substantially increasing, on a cohort basis, in oldest Italian males. Temporal pattern for laryngeal cancer in Italy was similar to that of lung cancer, thus suggesting that (cigarette) smoking has a greater impact on this cancer site as compared with alcohol. However, it is difficult to explain, on this basis alone, the totally diverging pattern for cancer of the larynx (downwards) and of the lung (upwards) observed among older Swiss males. These examples indicate that trend surface models are a useful summary guide to illustrate and understand the general patterns of age, period and cohort effects in cancer mortality.

Adult↗
PubMed1979

Time factor in oxygen transfer from mother to fetus.

The time factor in the oxygen transfer from mother to fetus was studied by the tcPO2 technique. When a fairly constant fetal circulation made estimation possible, the decrease in fetal tcPO2 synchronous with and due to the uterine contractions in more than 400 events was always delayed 50--60 sec. Since the time lag in the increase in fetal tcPO2 following administration of pure oxygen to the mother was found to be of the same order of magnitude, the placental part of the delay in the oxygen transfer from mother to fetus can be assumed to be 50--60 sec. This determination supports the prevalent hypothesis that type II dips or late decelerations in the fetal heart rate are caused by hypoxia while type I dips or early decelerations are initiated by other factors.

Female↗
PubMed1992

Treatment acceleration in radiotherapy: the relative time factors and dose-response slopes for tumours and normal tissues.

A published collation of data for control of head and neck cancer in over 4500 patients has been subjected to direct analysis to deduce dose-response, fractionation, and time parameters. The analysis confirms the presence of a significant time factor of the order of 0.5-0.6 Gy/day, deduced previously using various assumptions and normalisation procedures. In addition, the dose-response curve was characterised by Da = 29 Gy which contributed to long "effective" doubling times being deduced for tumour clonogens in the patient population as a whole. Some late-reacting normal tissues also show significant time factors, and furthermore, their dose-response curves are in general steeper than for tumours. Hence, care should be taken in accelerating treatments to improve local control, if the treatments are truly at tolerance regarding late-appearing major complications.

Dose-Response Relationship, Radiation↗
PubMed1991

Gait analysis of slope walking: a study on step length, stride width, time factors and deviation in the center of pressure.

Determination was made of step length, stride width, time factors and deviation in the center of pressure during up- and downslope walking in 17 healthy men between the ages of 19 and 34 using a force plate. Slope inclinations were set at 3, 6, 9 and 12 degrees. At 12 degrees, walking speed, the product of step length and cadence, decreased significantly (p less than 0.01) in both up- and downslope walking. The most conspicuous phenomenon in upslope walking was in cadence. The steeper the slope, the smaller was the cadence. The most conspicuous phenomenon in downslope walking was in step length. The steeper the slope, the shorter was the step length.

Adult↗
PubMed1979

Time factors in total body irradiation.

The role of time dose factors in the irradiation effect of the bone marrow has been investigated in mice by assessing the lethal dose 50% as a function of fraction number and dose rate. It is compared to the time dose effect in intestinal mucosa and lung, considered as critical tissues, for discussing the differential effect between these tissues.

Animals↗
PubMed1976

Antihemophilic factor concentrate therapy in von Willebrand disease. Dissociation of bleeding-time factor and ristocetin-cofactor activities.

Treatment of von Willebrand disease with two plasma antihemophilic factor (AHF) concentrates, cryoprecipitate and glycine-precipitated AHF, was compared. Both concentrates were equally effective in immediately raising the plasma levels of factor VIII, the factor VIII-related antigen, and the ristocetin-related von Willebrand factor (vWF) and in stimulating a secondary rise in plasma factor VIII. Given either concentrate, the vWF activity, the antigen, and factor VIII levels were normalized in a patient with von Willebrand disease. However, correction of the prolonged bleeding time and control of bleeding occurred only with the cryoprecipitate. The bleeding-time corrective factor and the ristocetin-related vWF or platelet-aggregating factor are dissociable, distinct activites.

Antigens↗
PubMed1976

[Time factors in human skin desquamations (author's transl)].

A clinical study of human skin desquamation has provided the variation of the isoeffect curve as a function of the fraction number and overall time. These results have been compared to ELLIS formula (N.S.D.). These results have been compared to relationships related to intestinal mucosa and lung. Differential effects are put in evidence between these tissues as a function of fractionation and overall time. Such differential effects are likely to exist between tumors and normal tissues; however the basic data are still missing for optimizing the time factors of the therapeutic irradiations.

Humans↗
PubMed1988

The neglected time factor and antihypertensive therapy. A pitfall in evaluating side effects in a cross-over study.

The aim of this study was to examine the influence of a time factor that may lead to inaccurate interpretation of data on the incidence of side effects in a double-blind study with drug cross-over. After a washout period, 58 patients with essential hypertension received either 20 mg of enalapril or 50 mg of atenolol. After two weeks, the dosage was doubled (to 40 mg of enalapril and 100 mg of atenolol) in those patients with diastolic blood pressure higher than 95 mm Hg. After four weeks of active treatment and a second two-week washout period, patients received the alternative antihypertensive agent under the same procedure and time schedule as in the first treatment phase. Four patients dropped out. Side effects were evaluated by questionnaire at weeks 2, 4, 8, and 10. In the 54 patients who completed the study, enalapril and atenolol led to almost identical blood pressure reduction in both treatment phases, indicating that pooling these data is a sound method. However, incidence of side effects was twice as high in phase 1 as in phase 2 and markedly decreased in each treatment phase, with no differences being observed between enalapril and atenolol. These results clearly demonstrate that pooling side effects data from a cross-over study may lead to quite wrong interpretations.

Antihypertensive Agents↗