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H Martínez

Publications and source records attributed to H Martínez.

At least 19 recordsLinked to original sources
PubMed2004

Negative ion formation and motion in a mixture of CCl4 and Ar.

This paper deals with the measurement of the mobility of negative ions in the mixtures of CCl4 with Ar with the CCl4 ratio up to 33.3%. The pulsed Townsend technique was employed to produce an integrated ionic avalanche over a range of the density-reduced electric field E/N for which ionization is either negligible or absent, and attachment processes are dominant, leading to the formation of mostly CCl-4. The E/N range of measurement was 1-50 Td (1 Td=10(-17) V cm(2)). Our measurements strongly suggest that attachment is the dominant process and only negative ions are formed.

Journal Article↗
PubMed2004

Nutritional status of indigenous children at boarding schools in northern Mexico.

OBJECTIVE: To assess the nutritional status of Tarahumara children at indigenous boarding schools. DESIGN: Cross-sectional comprehensive nutritional survey. SETTING: The schools sampled were located in indigenous municipalities of the northern Mexican state of Chihuahua. SUBJECTS: The study was carried out in 2001 among 331 children aged 6-14 y from a sample of five schools. Anthropometric measurements, a thyroid exam and capillary haemoglobin levels were obtained from the children. Serum concentrations of ferritin, iron, total iron-binding capacity, vitamin B(12), folic acid and zinc were collected from a subsample of 100 children. RESULTS: The prevalence of wasting and overweight (children 6-9 y) was 1.1 and 4.6%, respectively, and of underweight, risk of overweight and overweight (10-14 y) was 3.2, 5.1 and 0.6%, respectively. Stunting (6-12 y) was present in 22.3% of the children. The total goitre rate was 5.4%. The prevalence of anaemia was 13% (boys 11.4, girls 14.5%). Overall, 24.2% of the children were iron deficient (depletion 11.1%, deficient erythropoiesis 3%, iron deficiency anaemia 10.1%). No child had folic acid values <3 ng/ml, but 20.2% had low (<200 microg/dl) and 27.3% marginal (200-300 microg/dl) vitamin B(12) levels, and 80.2% had low zinc concentrations (<60 microg/dl). CONCLUSIONS: Nutritional underweight and stunting were similar to those reported in rural localities at the national level, but overweight was less prevalent in children aged 10-14 y. Various micronutrient deficiencies was identified including zinc and vitamin B(12), but the prevalence of iron and folic acid deficiency was lower than expected. These results suggest that Tarahumara children attending boarding schools may be the better-off children from these extremely poor and marginalized areas. SPONSORSHIP: Swedish Agency for Research Cooperation with Developing Countries and the Mexican Social Security Institute.

Adolescent↗
PubMed2003

[Complications of endoscopic retrograde cholangiopancreatography].

INTRODUCTION: Endoscopic sphincterotomy (ES) is commonly used to remove bile-duct stones and to treat other problems. We prospectively investigated complications and mortality of endoscopic retrograde cholangiopancreatography (ERCP). PATIENTS AND METHODS: Between june 6, 1998 and june 6, 1999 553 ERCP were performed in our centers. Inclusion criteria for protocol were: ERCP indication, complete follow-up and informed consent. We prospectively studied complications of ECRP in consecutive patients treated at 2 institutions (San Martin Hospital, La Plata, Argentina and Hadassah University Hospital, Jerusalem, Israel). The follow-up was done during 365 days with a clinical examination, laboratory test and ultrasonography to determine the possible complications. RESULTS: Of 553 ERCP, 43 had a complications; including pancreatitis in 16 cases, cholangitis in 12, hemorrhage in 5, perforation in 3 and miscellaneous in 7. 3-1) ES frequency: 241 patients (pts). 3-2) FOLLOW-UP: 365 days in 504 pts. 3-3) Sex and age: women 274 pts, men 230 pts. Age range 1 month to 90 year old. 3-4) Final diagnoses: choledocholitiasis (38.8%), strictures (18%), pancreatic cancer (4.3%), ampullary cancer (2.3%) and normal ERCP (24.4%). CONCLUSIONS: The rate of complications after ES can vary in different circumstances and is primarily related to the indication for the procedure and to endoscopic technique. Our percentage of complications (7.53%) coincide with consulted studies. Today, diagnostic ERCP has been challenged by magnetic resonance cholangiography (MRC). MRC provides images of the billary and pancreatic ducts that are nearly equal to those of ERCP without the procedural risk associated.

Adolescent↗
PubMed2001

The impact of a clinical training unit on integrated child health care in Mexico.

This study had two aims: to describe the activities of a clinical training unit set up for the integrated management of sick children, and to evaluate the impact of the unit after its first four years of operation. The training unit was set up in the outpatient ward of a government hospital and was staffed by a paediatrician, a family medicine physician, two nurses and a nutritionist. The staff kept a computerized database for all patients seen and they were supervised once a month. During the first three years, the demand for first-time medical consultation increased by 477% for acute respiratory infections (ARI) and 134% for acute diarrhoea (AD), with an average annual increase of demand for medical care of 125%. Eighty-nine per cent of mothers who took their child for consultation and 85% of mothers who lived in the catchment area and had a deceased child received training on how to recognize alarming signs in a sick child. Fifty-eight per cent of these mothers were evaluated as being properly trained. Eighty-five per cent of primary care physicians who worked for government institutions (n = 350) and 45% of private physicians (n = 90) were also trained in the recognition and proper management of AD and ARI. ARI mortality in children under 1 year of age in the catchment area (which included about 25,000 children under 5 years of age) decreased by 43.2% in three years, while mortality in children under 5 years of age decreased by 38.8%. The corresponding figures for AD mortality reduction were 36.3% and 33.6%. In this same period, 11 clinical research protocols were written. In summary, we learned that a clinical training unit for integrated child care management was an excellent way to offer in-service training for primary health care physicians.

Child↗
PubMed2000

Diagnostic value of tachypnoea in pneumonia defined radiologically.

OBJECTIVE: To evaluate whether sensitivity and specificity of tachypnoea for the diagnosis of pneumonia change with age, nutritional status, or duration of disease. METHODS: Diagnostic testing of 110 children with acute respiratory infection, 51 of whom presented with tachypnoea. The gold standard was a chest roentgenogram. Thirty five children had a radiological image of pneumonia; 75 were diagnosed as not having pneumonia. Sensitivity, specificity, and percentage of correct classification of tachypnoea, by itself or in combination with other clinical signs for all children, by age groups, nutritional status, and disease duration were calculated. RESULTS: Tachypnoea as the sole clinical sign showed the highest sensitivity (74%) and a specificity of 67%; 69% of cases were classified correctly. Sensitivity was reduced when other clinical signs were combined with tachypnoea, and there was no significant increase in correct classification, although specificity increased to 84%. In children with a disease duration of less than three days, tachypnoea had a lower sensitivity and specificity (55% and 64%, respectively), and a lower percentage of correct classification (62%). In children with low weight for age (< 1 Z-score), tachypnoea had a sensitivity of 83%, a specificity of 48%, and 60% correct classification. Sensitivity and specificity did not vary with age groups. CONCLUSIONS: Tachypnoea used as the only clinical sign is useful for identifying pneumonia in children, with no significant variations for age. In children with low weight for age, tachypnoea had higher sensitivity, but lower specificity. However, during the first three days of disease, the sensitivity, specificity, and percentage of correct classification were significantly lower.

Child, Preschool↗
PubMed2000

Does being a woman make a difference in professional practice? A qualitative view to the practice of rheumatology.

OBJECTIVE: To explore to what extent female rheumatologists perceived that gender had an influence on their professional practice or on their choice of specialty. METHODS: We collected data from 29 female rheumatologists and used qualitative and quantitative methods to describe the findings. RESULTS: Three groups of respondents were identified (cluster analysis). Most of these rheumatologists perceived that gender influenced the way they practiced, although the specific weights of the topics were different in the 3 groups. Gender also influenced these physicians' choice of specialty field. CONCLUSION: The differences in practice style may have a potential effect on health systems as feminization of the medical profession increases.

Female↗
PubMed1999

Nutritional preferences of a group of Streptosporangium soil isolates.

The nutritional preferences of twelve strains of genus Streptosporangium were studied as a first step in the design of production media to be used in a natural products screening program. The media ingredients included 20 alpha-amino acids, 35 carbon sources (monosaccharides, oligosaccharides, polysaccharides, polyalcohols and others), 22 complex sources (meals, peptones, yeast derivatives, etc.). The growth of these strains in the presence of these culture media ingredients and the production of inhibitory substances against Bacillus subtilis were analyzed in solid-phase cultures. The results show that the isolates studied did not exhibit a common trend in their preference of nutrient sources, either for to support their growth or the production of anti-B. subtilis substances.

Journal Article↗
PubMed1999

Seasonal diarrhoeal mortality among Mexican children.

The study investigated the effects on diarrhoeal deaths among under-5-year-old Mexican children of the following variables: season (summer or winter), region (north versus south), age group, and place of death. Examination of death certificates indicated that the distribution of deaths in 1989-90 was bimodal, with one peak during the winter and a more pronounced one during the summer. In 1993-94, however, the winter peak was higher than that in the summer (odds ratio (OR) = 2.04). These findings were due mostly to deaths among children aged 1-23 months (OR = 1.86). Diarrhoeal mortality was highest among children aged 6-11 months (OR = 2.23). During the winter, there was a significant increase in the number of deaths that occurred in medical care units and among children who had been seen by a physician before they died, but deaths occurring at home showed no seasonal variation. In the northern states, the reduction in diarrhoeal mortality was less in winter than in summer (OR = 2.62). In the southern states, the proportional reduction during the winter was similar to that in the summer.

Child, Preschool↗
PubMed1999

A clinical training unit for diarrhoea and acute respiratory infections: an intervention for primary health care physicians in Mexico.

In Tlaxcala State, Mexico, we determined that 80% of children who died from diarrhoea or acute respiratory infections (ARI) received medical care before death; in more than 70% of the cases this care was provided by a private physician. Several strategies have been developed to improve physicians' primary health care practices but private practitioners have only rarely been included. The objective of the present study was to evaluate the impact of in-service training on the case management of diarrhoea and ARI among under-5-year-olds provided by private and public primary physicians. The training consisted of a five-day course of in-service practice during which physicians diagnosed and treated sick children attending a centre and conducted clinical discussions of cases under guidance. Each training course was limited to six physicians. Clinical performance was evaluated by observation before and after the courses. The evaluation of diarrhoea case management covered assessment of dehydration, hydration therapy, prescription of antimicrobial and other drugs, advice on diet, and counselling for mothers; that of ARI case management covered diagnosis, decisions on antimicrobial therapy, use of symptomatic drugs, and counselling for mothers. In general the performance of public physicians both before and after the intervention was better than that of private doctors. Most aspects of the case management of children with diarrhoea improved among both groups of physicians after the course; the proportion of private physicians who had five or six correct elements out of six increased from 14% to 37%: for public physicians the corresponding increase was from 53% to 73%. In ARI case management, decisions taken on antimicrobial therapy and symptomatic drug use improved in both groups; the proportion of private physicians with at least three correct elements out of four increased from 13% to 42%, while among public doctors the corresponding increase was from 43% to 78%. Hands-on training courses thus seemed to be effective in improving the practice of physicians in both the private and public sectors.

Acute Disease↗
PubMed1998

The quality of private and public primary health care management of children with diarrhoea and acute respiratory infections in Tlaxcala, Mexico.

In Tlaxcala, Mexico, 80% of the children who died from diarrhoea or acute respiratory infections (ARI) in 1992-1993 received medical care; in more than 70% of cases it was provided by a private general practitioner (GP). The present study evaluated the quality of case management by private and public GPs to children under five years of age with diarrhoea and ARI. During the clinical observation, the treatment and counselling given to the mother were assessed with the WHO guidelines as reference standard. A total of 41 private and 40 public GPs were evaluated for the management of diarrhoea, and 59 private and 40 public GPs for the management of ARI. For diarrhoea, half of the private GPs gave inadequate rehydration therapy, 63% gave incorrect advice on diet, 66% and 49% made an incorrect correct decision in the prescription of antimicrobial and symptomatic drugs, respectively. Public GPs generally performed better in diarrhoea management: 7% gave inadequate rehydration therapy, 13% gave wrong advice on diet, 3% made a wrong decision in the prescription of symptomatic drugs and 28% gave a wrong decision in antimicrobial prescription. In the management of ARI, 66% and 58% of private GPs made a wrong decision in the prescription of antimicrobial and symptomatic drugs, respectively, compared to 30% and 20% of public GPs, respectively. Counselling to the mother given by both private and public GPs was considered inadequate in most cases of diarrhoea and ARI. These results clearly show that private doctors, as important providers of medical care, need to be included in the strategies to improve the quality of care of children with diarrhoea and ARI. Future research needs to address the determinants of the clinical practice of private doctors in countries like Mexico.

Child↗
PubMed1997

Implementation of conditions of the inoculum stage for Streptosporangium cultures.

Different factors concerning the inoculum stage of cultures classified within the genus Streptosporangium have been studied. These factors include a comparison among several inoculum media and sources, the influence of aeration and volume of medium in the growth of the cultures, and the effect of the inoculum size on the course of the production of two antibacterial substances. The results suggest that a slight variation in the status of the seed culture (age, biomass concentration, etc.) affect the course of the batch culture during its initial exponential phase (3-5 days), whereas, at longer times, the behavior of the culture does not depend greatly on the characteristics of the inoculum. The results obtained have allowed to define a set of conditions producing the maximum increase of biomass in the minimum time.

Actinomycetales↗
PubMed1996

[Superstitions around teeth].

Popular beliefs in magical medicines or manneuvers to cure dental pains, have been at every time subject of curiosity and even of credulity for common people. Writers and story-tellers describe medicines and habits used to relief or get rid of toothache, in interesting and humorous tales.

History, Modern 1601-↗
PubMed1996

Impact of oral rehydration and selected public health interventions on reduction of mortality from childhood diarrhoeal diseases in Mexico.

Reported are the results of an analysis of mortality trends from diarrhoeal diseases among under-5-year-olds in Mexico between 1978 and 1993 in relation to the impact of education, basic sanitation, and selected medical care practices. The study period was divided into three stages; the first pre-dated the widespread application of oral rehydration therapy (ORT); the second, covered the implementation of a nationwide programme promoting ORT; and the third included additional measures, such as immunization and improvements in basic sanitation. Mortality rates decreased progressively, at an average of 1.8% per year in the first stage, 6.4% in the second, and 17.8% in the third. The importance of literacy campaigns for women and the promotion of ORT was confirmed. Both of these measures reduced mortality; however, a greater reduction resulted from a massive immunization campaign against measles and improvements in sanitation (expansion of the drainage and piped water systems, improved water chlorination procedure, and effective prohibition of the use of sanitary sewage for vegetable irrigation).

Adult↗
PubMed1996

Methodological issues for eliciting local signs/symptoms/illness terms associated with acute respiratory illnesses.

Acute respiratory infections (ARI) are among the principal causes of mortality of children under 5 years of age. Most deaths are due to pneumonia, which, when timely identified and properly treated, could be avoided. An effective case management scheme, based on early recognition of pneumonia and prompt antibiotic treatment, relies on early recognition of alarm signs by mothers and community health workers. For mothers to understand and act on advice from health workers, language and concepts commonly used by mothers should be utilized. The present study was carried out to compare the relative effectiveness of two different methods to elicit local terms used by mothers to refer to ARI symptoms/signs/treatments. A comparison was made among the terms elicited by a free listing of common terms mentioned by mothers in relation to ARI, and the terms they recognized when looking at a video that showed children with different ARI signs. The video was shown in a community and a clinical setting, in order to identify strengths and weaknesses of showing it in these settings. The video elicited more signs dealing with serious illness, respiratory distress and general malaise, but missed non-visual signs, such as fever, lack of appetite or pain. Also, mothers tended to be distracted by trivial signs, such as skin color. Free listing was easier to administer and elicited more non-life-threatening symptoms/signs, but mothers were more prone to drift away and mention terms not related to respiratory illness. Showing the video in the clinic elicited more medical-related terms, and was easier to show than in the community. In conclusion, choice of either of the two methods depends on the researcher's purpose. Using both methods produced a larger list of terms associated with ARI.

Academies and Institutes↗
PubMed1995

[Fictions and stories].

A short and interesting work, where the author of "The secret tooth", exposes some opinions about fiction and story, words he considers should not be opposed, but really on the contrary, be harmonized to contribute with their alliance for personal joy of readers. Writers like Joyce, Caillois, Updike, and others, are quoted for renewing texts with reports referred to Dentistry.

Dentistry↗
PubMed1995

From research to public health interventions. I. Impact of an educational strategy for physicians to improve treatment practices of common diseases.

Errors in treating common diseases occur very frequently in primary health care practice. While many of these mistakes are not life-threatening, the costs of abuse in drug prescription may be greatly increased. An educational strategy aimed to improve physicians' prescribing practices for acute diarrhea (AD) and acute respiratory infection (ARI) was developed as a research study, involving three medical care units. The strategy was largely based on promoting active participation of the trainees in the whole process, including: (a) group participation in a literature review of updated articles related to management of AD and ARI; (b) analysis of prescribing practices before the intervention; (c) participation in the development of a clinical algorithm for the therapeutic management of these illnesses; and (d) discussion of the usefulness of the algorithm during peer review committee meetings. Successful results of this intervention, as judged by the improvement of treatment practices and the persistence of changes for up to 2 years after the intervention, as well as its ease of application and low costs, motivated its extension to a health District and a State. In these sites, the intervention was in charge of medical leaders from the clinics and medical heads of the local health systems, respectively. The extension of the educational strategy was accompanied by a relative reduction in AD from 46.7% to 6.5% and in ARI from 32.6% to 8.5%. However, the benefit-cost ratio showed a dramatic increase when comparing results from the research study and from the State intervention, for both AD (from 3.3 to 4.4) and ARI (from 16.2 to 21.6), for an overall net increase of 33.3%. Based on these results, the educational strategy was adopted by the National Program for the Control of Diarrheal Diseases, and was used to train public health physicians throughout the country, from 1992 to 1994.

Acute Disease↗