In this paper we report the oldest geologic world record of Ptychodus mortoni, from the Vallecillo Member (Agua Nueva Formation), at Vallecillo, Nuevo León, northeastern Mexico. The presence of the ammonite Watinoceras coloradoense, allows the placement of the sediments of…

The association between gastrointestinal H. pylori infection and thrombocytopenia was studied in a single institution in Mexico, over a 5-year period. In 99 individuals with H. pylori infection, the prevalence of thrombocytopenia was 14%, whereas in 23 consecutive patients with…

OBJECTIVE: To determine the associations of metabolic syndrome (MS) with residential area and lifestyle in men from Oaxaca, Mexico. MATERIAL AND METHODS: A cross-sectional study was conducted in 1998 in 325 apparently healthy men 35 to 65 years of age…

A new unusual Uropodina mite (Uroobovella vazquezae sp. nov.) is found in the tropical part of Mexico. The new species is easy to separate from the other known Uroobovella species on the basis of the cavities on dorsal and ventral…

OBJECTIVE: Evaluate the relationships between AgNORs polymorphisms and squamous intraepithelial lesions (SIL) and squamous cell carcinoma (SCC) with HPV infection. MATERIALS AND METHODS: A study was carried out on sixty women from the state of Guerrero, Mexico. HPV detection was…

OBJECTIVE: To quantify the physical activity (PA) of students and describe the school environment surrounding PA. MATERIAL AND METHODS: Between November 2005 and March 2006, in Mexico City, we conducted quantitative and qualitative observations to describe the PA and the…

Sixty species of calcareous nannoplankton from the Tepetate formation were recovered from a drill hole near Las Pocitas, Baja California Sur. In spite of its low abundance and erratic distribution throughout the sedimentary column, the great amount of reworked species,…

To investigate the effects of hydrothermal alteration on the chemistry of volcanic rocks, we analyzed the whole rock chemical composition (major and trace elements, including rare-earth elements - REE) of two distinct portions of a drill well core sample from…

The objective of this paper is to present a model to design effective Production Improvement Programs (PIP) in order to contribute in the solution of the problematic situations generally faced by the Mexican manufacturing micro, small and medium-sized enterprises (M-SME).…

A suite of mafic dikes intrudes polydeformed, greenschist facies, metapsammites and metapelites of the Salada unit in the eastern part of the Acatlán Complex, southern Mexico. The age of the dikes is constrained by the youngest detrital zircon in the…