81 patients living at La Paz (3,600-4,000 m altitude) and suffering from chronic polycythaemia, with an haematocrit greater than 57% were studied. They were selected on clinical and spirometric criteria to exclude from the study patients with associated pulmonary diseases. 45% of them were overweight (group O). The group of patients having a normal weight was divided into two equal groups: "young" patients (less than 35 years, J) and "old" patients (greater than 35 years, V). The important findings of this study were: 1) the existence of hypoxaemia in all groups: compared to the control group, the mean differences are -2 kPa for O and V groups and -1.3 kPa for J group; 2) the presence of slight hypercapnia (+0.3 kPa in J and V groups; +0.5 kPa in O group), excluding diurnal hypoventilation as the major source of hypoxaemia; 3) a significant linear correlation between the increase in PaCO2 and haematocrit in O and (J + V) groups; 4) a significant linear correlation between hypoxaemia and the increase in haematocrit, particularly in group J, but also in O and (J + V) groups; hypoxaemia is also well correlated with age in (J + V) group: PaO2 (kPa) = 11.42 -0.025 Age (yr) -0.061 Hct (%) The classical assumption of a chronic hypoventilation syndrome producing a progressive increase in haematocrit is discussed. Haematocrit is suspected as a causative factor of hypoxaemia, itself a well known factor producing polycythaemia. This mechanism could be the source of a vicious circle.

Adolescent↗

PubMedDate not supplied

[A study of some conditioning factors for hydatidic endemic in Tierra del Fuego Province (Chile) (author's transl)].

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Animals↗

PubMedDate not supplied

[Determination of alpha fetoproteins in patients infected with virus B and C. Preliminary report].

The presence of detectable levels of aFP was investigated through RIA in 78 serum samples classified as follows: 32 samples from healthy volunteers (group A), 15 anti-HCV positive sera, 19 samples from HBV Chronic carriers (Group B), and 12 sera from a group of anti-core positive individuals, (Group C). Increased aFP levels, upper to the calculated maximal limit (Above 2.6 ng/ml) were detected in 2 individuals from Group A, in 2 HCV positive sera and in 6 HBV chronic carriers. None of the Group C demonstrated increased aFP value. Two B positive sera with augmented aFP activity showed significantly elevated values of this protein 13 and 20 fold upper than maximal limit. In Venezuela, aFP levels the HBV chronic carriers do not appear to be comparable to the reported values in HBV hyper-endemic countries. The need to analyze aFP values in normal groups is emphasised.

Adult↗

PubMedDate not supplied

ACTH secreting pituitary microadenomas disclosed only by gadolinium DTPA enhanced MRI.

PURPOSE: To assess the usefulness of Gd-DTPA enhancement in disclosing microadenomas of the pituitary gland that had not been demonstrated by non enhanced MRI in patients with Cushing's disease. METHODS: Six patients with Cushing's disease underwent pre and post enhancement MRI scanning and the findings were correlated at surgery and confirmed by histological and immunohistochemistry studies of the surgical specimen. RESULTS: In all cases post enhancement MR scans demonstrated circumscribed hypointense foci that corresponded well with the location and extension of the adenomatous tissue found at surgery. Selective removal of the microadenomas failed to improve the clinical and laboratory abnormalities in two of the six patients. Such cases did not present residual hypointense foci in the post-operative Gd-DTPA enhanced MRI. CONCLUSION: Results suggest that Gd-DTPA enhanced MRI is useful to detect pituitary microadenomas; however, the abnormalities of the pituitary tissue may extend beyond the abnormal imaging.

Adenoma↗