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I Alonso

Publications and source records attributed to I Alonso.

30 records · Page 2Linked to original sources
PubMed1997

Computation of time-specified tolerance intervals for hybrid time series with nonequidistant sampling, illustrated for plasma growth hormone.

The ideal reference interval for a variable of clinical interest would be specific for all deterministic factors affecting that variable, including the time of sampling in relation to biological rhythms. In particular, growth hormone is characterized in children by circadian and ultradian variability, with high peaks of secretion occurring mainly during sleep. For clinical applications, the use of tolerance intervals has been recommended, and they should substitute, whenever possible, for prediction limits. In the case of hybrid data (time series of data collected from a group of subjects), such a tolerance interval could be very difficult to determine following a parametric approach similar to the procedure used for the computation of prediction intervals, especially when consideration of both within-subjects and among-subjects variances is wanted. Accordingly, we have developed a nonparametric method for the computation of such tolerance intervals. Because the method is based on bootstrap techniques, it does not require the assumption of normality or symmetry in the data and is also more appropriate when dealing with small samples. The method was used to establish time-qualified reference limits for a series of growth hormone sampled around the clock in groups of prepubertal children differentiated according to stature. The use of these tolerance intervals may eliminate many false-positive and false-negative diagnoses that might be obtained when relying on time-unspecified single samples. The provision of such tolerance limits introduces time-specification and time-structure evaluation into prevention, diagnosis, and treatment of growth disorders.

Activity Cycles↗
PubMed1996

[The main causes of death in Spain, 1992; comment].

BACKGROUND: To study the mortality from the leading causes of death in Spain in 1992 and trends since 1980. POPULATION AND METHOD: The number of deaths was obtained from mortality statistics. We included the 12 causes with the highest mortality rates in 1992 and calculated for each cause of death the age adjusted mortality rates for each year in the study period, the percent change from 1990 to 1992 and from 1980 to 1992, and the adjusted ratio of rates between men and women in 1992. RESULTS: The leading causes of death in 1992 were malignant neoplasms, with 24.3% of deaths and a mortality rate of 205.6 per 100,000 population; diseases of the heart, with 22.6% and a rate of 191.8 per 100,000; and cerebrovascular disease, with 12.7% and a rate of 107.6 per 100,000 population. Between 1980 and 1992 the adjusted mortality rate increased for four causes of death: malignant neoplasms; chronic obstructive pulmonary disease and similar diseases; nephritis, nephrotic syndrome and nephrosis; and suicide. From 1990 to 1992, the adjusted mortality rate declined for all other causes of death. From 1990 to 1992, the adjusted mortality rate declined for all causes of death except for malignant neoplasms and human immunodeficiency virus (HIV) infection, which rose 0.4% and 69%, respectively. The adjusted mortality rate was higher in men than in women for all causes of death except for diabetes mellitus and atherosclerosis. CONCLUSIONS: Except for malignant neoplasms and HIV infection, mortality from all other leading causes of death declined in 1992 with respect to 1990, independently of the trend experienced by each cause of death in the eighties.

Cause of Death↗
PubMed1996

Study of lens autofluorescence by fluorophotometry in pregnant patients with diabetes.

PURPOSE: Lens autofluorescence originates from an accumulation of fluorescent substances such as the tryptophan-derived residues and glycosylated protein aggregations, which are associated with the process of cataractogenesis and lens aging. The purpose of this investigation is to determine whether pregnancy alters the typical constituents of the lens autofluorescence in patients with diabetes and, if so, to what degree this may occur. METHODS: Lens autofluorescence was studied with fluorophotometry in 127 eyes of 72 individuals: 23 control subjects, 6 healthy pregnant women, 21 patients with diabetes, and 44 pregnant patients with diabetes. RESULTS: The autofluorescence values were 311 +/- 130 ng/ml, 253 +/- 40 ng/ml, 378 +/- 110 ng/ml, and 562 +/- 164 Eq ng/ml (Eq ng/ml = Ng/ml equivalent fluorescein) in the four groups, respectively. The difference between the nonpregnant and pregnant patients with diabetes was significant (P < 0.001). CONCLUSION: These results suggest that there is an important deterioration in the metabolic state of the lens during gestation in patients with diabetes, as is the case for diabetic retinopathy.

Adult↗
PubMed1990

Ultrasound study of acute appendicitis in children with emphasis upon the diagnosis of retrocecal appendicitis.

Acute appendicitis in children frequently presents equivocal clinical manifestations. Delay of the proper diagnosis and unnecessary laparotomies are common. Abdominal ultrasound has proved to be useful in the diagnosis of acute appendicitis in adults. We have performed a preoperative ultrasound study in 368 children with acute appendicitis. Among the, 92 had a retrocecal appendicitis. Ultrasound established the correct diagnosis in 92.6% of patients, and in 94.5% of those with a retrocecal appendicitis. At our institution an abdominal sonography is performed on any child with a doubtful clinical diagnosis of acute appendicitis, helping the surgeon to take the decision to perform a laparotomy.

Acute Disease↗
PubMed1989

[New aspects of gallbladder pathology in children].

We have reviewed in a retrospective study 38 children treated in our Hospital, during the last seven years, because of non congenital gall-bladder disease. The diagnosis established were cholelithiasis 58 for 100, hydrops 26 for 100, acalculous cholecystitis 13 for 100 and hemobilia in one child. Cholelithiasis was more frequent in females at a rate of 2/1. Just the opposite incidence was found for acalculous gall-bladder pathology. Mean age at time of first hospitalization was 7.6 years for the cholelithiasis group and 6.6 years for the rest. Symptoms in order of frequency were abdominal pain, vomiting and fever. Abdominal sonography has been basic in establishing to correct diagnosis in practically all cases. Our most interesting finding has been the clinical manifestations of patients with "Hydrops", consisting of abdominal pain which disappears spontaneously after 24 to 48 hours. The diagnosis has been established only after performing abdominal sonographic studies in children with abdominal pain of unclear etiology.

Acute Disease↗
PubMedDate not supplied

Evaluation of the Functional Assessment of Cancer Therapy-General Questionnaire (FACT-G) in a South American Spanish speaking population.

There is an increasing interest by health care providers, not only in the effectiveness of cancer treatments, but also in patients' quality of life (QOL). The objective of the present study is to validate the Functional Assessment of Cancer Therapy-General (FACT-G) Version 2 as a measure of the QOL in a sample of 140 Uruguayan patients with cancer of varied sites, at different stages of the disease and under different forms of treatment. Reliability of the FACT-G was evaluated and showed high coefficients (Cronbach's alpha) in each of the subscales and in the total questionnaire score. It was also capable of discriminating among different groups of patients. We conclude that the FACT-G is a brief and easy to use questionnaire, that showed acceptable reliability and validity and good feasibility for use as a research instrument among Uruguayan cancer patients.

Adult↗
PubMedDate not supplied

[Bilateral chylothorax after gastric surgery].

Chylothorax is a lymphatic effusion of chylous in the pleural space due to thoracic duct obstruction or injury. The most frequent aetiology is cancer; it is also related to chest trauma and iatrogenic. We describe the case of bilateral chylothorax in a 76-year-old woman, right predominant, during the post-operational phase of gastric surgery. This presented itself with respiratory insufficiency and tachycardia without initial haemodynamic compromise. It presented a favourable evolution after conservative treatment, cessation of oral intake and TPN and chest tube during 10 to 14 days.

Aged↗