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M Montes

Publications and source records attributed to M Montes.

At least 19 recordsLinked to original sources
PubMed1992

Quantitative structure-activity relationship study of the biophysicochemical behavior of nitrosamine.

The partition coefficients of 14 aliphatic nitrosamines were measured in six water-organic solvent systems. Correlations between Hansch's hydrophobic parameter (pi) and Kier and Hall's topological index (1 chi) allowed pi to be substituted by 1 chi in the structure-activity correlations of the carcinogenicity data of the nitrosamines studied. The use of high-performance liquid chromatographic capacity factors of nitrosamines in these correlations is also discussed.

Chemical Phenomena↗
PubMed1992

Low risk of mother to infant transmission of hepatitis B virus in Guipúzcoa (Basque country, northern Spain).

The prevalence of HBsAg carriers in 18,196 pregnant women (64% of women who gave birth in Guipúzcoa in 1986-1991) was 0.61% (0.43% for the last two years of the study). Three of the carriers were also HBeAg/HBV-DNA positive and two were anti-HDV positive. Anti-HBc prevalence was 6.5% in 602 20-40 year old women and 1.6% in 428 girls 10-11 years old (0.47% of gypsy ethnic subjects are not included).

Adult↗
PubMed1992

[Peritoneal pneumococcal infections].

The clinical-microbiological characteristics of 13 patients iun whom Streptococcus pneumoniae (Pneumococcus) was isolated from the peritoneum over eight and a half years in a third grade hospital are reviewed. It is noteworthy the fact that only in 7 cases primary or spontaneous peritonitis were treated; the remaining cases were secondary to perforation or genital infection in females. The presence of antibiotic resistance in pneumococcus was high and global mortality was low.

Adolescent↗
PubMed1991

Primary gallbladder carcinoma: imaging findings in 50 patients with pathologic correlation.

Different diagnostic imaging modalities [contrast cholangiography, ultrasonography, and computed tomography (CT)] in a large group of patients with proven gallbladder carcinoma are reviewed. Noninvasive cross-sectional imaging methods strongly correlated with the different gross pathologic types of gallbladder carcinoma. The most common observed type was a mass replacing the gallbladder (39%). Other types observed either by sonography and/or CT were a focal/diffuse gallbladder wall thickening and the presence of an intraluminal polypoid mass. Despite the improvement in several imaging modalities, most of the preoperatively diagnosed gallbladder carcinomas were in advanced stage (84%). A combined approach using noninvasive diagnostic methods and percutaneous aspirative biopsies may reduce the number of explorative laparotomies in the final diagnosis of gallbladder carcinoma.

Aged↗
PubMed1991

[Resistance to erythromycin in Streptococcus pneumoniae].

A total of 640 S. pneumoniae isolates from different clinical samples obtained from patients (not including carriers) over a 10 years period were studied. Global resistance to erythromycin (MIC greater than or equal to 1 microgram/ml) was 9.1% (8.1% with MIC greater than or equal to 8 micrograms/ml). Resistance was more prevalent in serotypes 6, 14, and 19, either in absolute number or in relation to the total number of strains in each serotype. A total of 16% of strains isolated from ear fluid specimens and bronchial secretions were resistant, but only a 4.5% of blood culture isolates showed also resistance to erythromycin. Resistance was found more frequently on pediatric patients. Although the highest resistance rate was found during the last year (15% of all 1990 isolated strains or 13.9% if the period also includes the first 1991 quarter) we did not find a gradual increase over time. Most of the resistant strains showed also resistance to tetracycline and other antimicrobial agents. Overall, 94.8% of strains showed multiple resistance (combined resistance to at least 2 other different antibiotics, not including clindamycin resistance, which always matches erythromycin resistance), and 60.3% showed resistance to penicillin. The multiply-resistant pattern and the similarity of isolated strains suggest an epidemiologic behaviour that not necessarily has to be linked to higher erythromycin use.

Adult↗
PubMed1990

Acoustic artifacts and reverberation shadows in gallbladder sonograms: their cause and clinical implications.

From among more than 7000 sonographic examinations of the gallbladder performed over a period of 2 years, different types of acoustic artifacts were observed in 42 patients. Artifacts originated in the gallbladder wall in 37 cases and within the lumen in 5 cases. Eighteen patients had symptoms related to the hepatobiliary area. Twenty-four patients were fully asymptomatic although cholelithiasis was demonstrated in 8. In 21 cases (50%) some type of gallbladder pathology was associated with the presence of acoustic artifacts. Thirteen patients were cholecystectomized and the associated gallbladder pathology consisted of cholelithiasis (N = 5), cholesterolosis (N = 2), adenomyomatosis (N = 2), emphysematous cholecystitis (N = 2), and acute cholecystitis (N = 2). In 3 of these patients a sonographic/pathologic correlation was established. Only 5 of the 18 symptomatic patients presented acoustic artifacts in an otherwise normal gallbladder. Recognition of those pathological conditions favorable to the appearance of artifacts and reverberation shadows is extremely useful for differentiating merely clinically irrelevant anomalies from those that require prompt management.

Acoustics↗
PubMed1990

Hydatid disease of the spleen: imaging findings in nine patients.

Splenic involvement is uncommon in patients with hydatid disease. The radiologic and clinical findings in nine patients with splenic hydatidosis are described. The three men and six women were 41-76 years old (mean, 58 years). Their histories and physical findings, the results of serologic tests for hydatidosis, and imaging procedures were evaluated. Plain abdominal radiographs were obtained in all nine patients, sonograms in six, and CT scans in seven. Plain films showed calcification of the cyst wall in four of the nine patients. On sonograms, five lesions were anechoic and one was echogenic. On CT scans, all lesions except one were of lower attenuation than the surrounding spleen. None of the lesions enhanced after administration of IV contrast material. Although rare, splenic hydatidosis should be included in the differential diagnosis when a cystic splenic lesion is identified with sonography or CT.

Adult↗
PubMed1979

Benign prostatic hyperplasia in an XX man.

A sixty-nine-year-old white phenotypic male who was being investigated for a myeloproliferative disorder, was found to have an XX karyotype in all cells examined in bone marrow, lymphocytes, and skin fibroblast cultures. Despite essentially no testosterone in the plasma, he also suffered from severe prostatic hyperplasia, a finding not reported previously in patients with this genotype. While endocrine studies showed normal follicle-stimulating hormone, the luteinizing hormone level was twice the upper limit of normal and estrogens were in the normal female range. Except for complete absence of Leydig cells, testicular histology resembled that usually found in Klinefelter syndrome. The patient died of the combined effects of the myeloproliferative disease and urinary tract obstruction. The mechanism of occurrence of the sex chromosome anomaly as well as the cause and implication of the unusual finding of prostatic hyperplasia are discussed.

Aged↗