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Biomedical subjects

G Sanchez

Publications and source records attributed to G Sanchez.

88 records · Page 5Linked to original sources
PubMedDate not supplied

Changes in the rectal mucosa induced by hypertonic enemas.

The aspect of the rectal mucosa after administration of hypertonic enemas is occasionally confused with the macroscopic appearance of quiescent ulcerative colitis. Criteria for a diagnosis of enema reaction were derived from a retrospective series and tested prospectively on 11 healthy volunteers. Photographs and biopsies were obtained before and after administration of a sodium phosphate hypertonic enema. Three observers evaluated blindly the "before" and "after" macroscopic and microscopic pictures, graded the features, and made an overall diagnosis. In random studies, two observers mistakenly classified a macroscopic picture, but all correct histologic diagnoses of "before" and "after" biopsies. In decreasing order of discriminating power, the following features of an enema reaction were found to be useful: separation and mucous depletion of the glands (no observer variation), increase in mucosal fragility in 91 per cent of cases (82--100 per cent), edema of the lamina propria in 88 per cent (73--100 per cent), straightening of the basal membrane in 82 per cent (73--91 per cent) and an increase in extruded mucus in 70 per cent (18--100 per cent). In 39 per cent of cases (36--45 per cent), erythrocytes appeared focally in the lamina propria. The effects of hypertonic enemas can be recognized on biopsy.

Adult↗
PubMedDate not supplied

An integrated methodological approach to the computer-assisted gas chromatographic screening of basic drugs in biological fluids using nitrogen selective detection.

This paper presents the methodological aspects of a computerized system for the gas-chromatographic screening and primary identification of central nervous system stimulants and narcotic analgesics (including some of their respective metabolites) extracted from urine. The operating conditions of a selective nitrogen detector for optimized analytical functions are discussed, particularly the effect of carrier and fuel gas on the detector's sensitivity to nitrogen-containing molecules and discriminating performance toward biological matrix interferences. Application of simple extraction techniques, combined with rapid derivatization procedures, computer data acquisition, and reduction of chromatographic data are presented. Results show that this system approach allows for the screening of several drugs and their metabolites in a short amount of time. The reliability and stability of the system have been tested by analyzing several thousand samples for doping control at major international sporting events and for monitoring drug intake in addicts participating in a rehabilitation program. Results indicate that these techniques can be used and adapted to many different analytical toxicology situations.

Body Fluids↗
PubMedDate not supplied

Ultrastructure of the organ of Jacobson and comparative study with olfactory mucosa.

The organ of Jacobson has been studied in lizards, rats, guinea pigs, rabbits and dogs by means of embedding in nitrocellulose, semithin sectioning, and electron microscopy. The various elements of the organ in the species studied have been analysed and a comparative study carried out between the sensory portion of the organ and the olfactory epithelium.

Animals↗
PubMedDate not supplied

[Immunofluorescent deposits in normal rheumatoid skin].

Predominantly IgM immunofluorescent deposits have been found in 30% of normal, non exposed skin in a group of rheumatoid arthritis patients. Neither clinical nor biological correlation have been found. Because one case with cryoglobulinemia was positive, study of other non lupus, cryoglobulinemic, immune complexe type of diseases has been done. The results were negative. Further investigations are needed to explain this observation.

Arthritis, Rheumatoid↗
PubMedDate not supplied

Endomyocardial biopsy after heart transplantation in children.

Clinical evaluation, physical examination, and noninvasive testing have been suggested as adjuncts to endomyocardial biopsy for diagnosing acute graft rejection in children after heart transplantation. Because the consequences of delayed diagnosis or unnecessary treatment of rejection may be serious in pediatric transplant recipients, we reviewed our experience with repeated endomyocardial biopsy in seven children (aged 6 months to 19 years) and assessed the sensitivity and specificity of clinical and noninvasive data for diagnosing acute rejection. There were no serious complications in 71 biopsy procedures. In no patient did the presence of abnormal clinical findings or noninvasive testing coincide with treatable rejection that was proved on biopsy. However, there were nine episodes of treatable rejection in the absence of abnormal physical findings or noninvasive studies. At this time we consider repeated endomyocardial biopsy to be a feasible and safe procedure in infants and children and do not consider clinical findings and noninvasive testing sufficient to make therapeutic judgments in regard to acute graft rejection.

Adolescent↗
PubMedDate not supplied

Chondrosarcoma of the hand.

A case of chondrosarcoma of the hand recurred 4 times over a period of 32 years. Forty-seven cases of hand chondrosarcomas have been found in the literature. Histological diagnosis is difficult in differentiating chondrosarcomas from benign chondromas. Pain and swelling are the main symptoms of recurrence. The diagnosis is established by arteriography and excisional biopsy. Extraskeletal hand chondrosarcomas do not metastasize and other hand chondrosarcomas do so only rarely. Block excision of localized amputation is the treatment of choice.

Aged↗