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991.
Ana María Salinas-Martínez Jimena Estefanía Gaspar-Rivera Oscar Juárez-Pérez José Roberto Montañez-Sauceda Georgina Mayela Núñez-Rocha Francisco Javier Guzmán-de-la-Garza Álvaro Mathiew-Quirós 《Journal of community health》2017,42(2):252-259
Failures in repeat mammography decrease the potential benefits of screening; however, it is notable that the recent use of mammography is more frequently studied than repeat use. We estimated the prevalence and analyzed determinants for repeat mammography among women from Mexico, a developing country of Latin America. It was a two-stage study with an initial cross-sectional design (n?=?1045) and a final case-control design that involved women of at least 45 years of age with no history of breast, ovarian, or uterine cancer. Case subjects were those with three or more mammograms in the last 5 years, with the last one carried out within the last two years (n?=?444); control subjects included those who underwent ≥3 mammograms throughout their life with the most recent carried out >2 years ago (n?=?444). Through interviews, we evaluated context-dependency, fulfillment of expected outcomes, self-efficacy, and risk perception, among other factors. We estimated the prevalence with 95?% confidence intervals (CI), and odds ratios (OR) using multivariate binary logistic regression. The prevalence of repeat mammography was 40.4?% (95?% CI 37.4–43.4). Self-efficacy demonstrated the highest effect on repeat use (OR 7.7, 95?% CI 4.7–12.6), followed by awareness context-dependency (OR 4.9, 95?% CI 3.3–7.2), the use of Papanicolaou testing (OR 3.5, 95?% CI 2.3–5.2), the fulfillment of expected waiting time outcome (OR 2.4, 95?% CI 1.2–4.7), and context-dependency related to self-referral/health provider referral (OR 2.4, 95?% CI 1.7–3.4), independent of risk perception, age, education, and positive emotional state of mind. The study showed a need for increasing the prevalence of promoting awareness of the determining factors of repeat mammography, which is a necessary component in the early detection of breast cancer. 相似文献
992.
Daniel Limonta Virginia Capó Griselda Torres Ana B Pérez María G Guzmán 《Journal of clinical virology》2007,40(1):50-54
BACKGROUND: Apoptosis, or programmed cell death, has been implicated in dengue hemorrhagic fever/dengue shock syndrome (DHF/DSS) pathogenesis. OBJECTIVES: To determine the in vivo apoptosis contribution to the pathogenesis of fatal DHF/DSS during a Cuban dengue epidemic. STUDY DESIGN: We detected apoptosis by the TdT-mediated dUTP Nick-End Labeling (TUNEL) technique and dengue virus (DENV) antigens by an immunohistochemical assay in different tissues from six individuals who died of DHF/DSS during the Santiago de Cuba DENV-2 epidemic in 1997. RESULTS: DENV antigens were immunolocalized mainly in hepatocytes. Apoptotic cells were found in five of the six cases studied. Apoptosis was demonstrated in liver, brain, intestinal and lung tissues. Severe brain hypoxia and ischemia in the studied subjects during DHF/DSS probably might induce apoptosis in cerebral cells. Apoptotic microvascular endothelial cells (ECs) in pulmonary and intestinal tissues, a finding only previously reported in vitro, are likely related to vascular plasma leakage manifested by the individuals. CONCLUSIONS: Apoptosis was demonstrated in cerebral cells, white blood cells, intestinal and pulmonary microvascular ECs from Cuban fatal cases of DHF/DSS. As far as we know, these findings have not been previously reported in DHF/DSS. Our results indicate there is very likely an in vivo contribution of apoptosis to the pathophysiological mechanisms of DHF/DSS. 相似文献
993.
Mohamed F Fogal T Dominguez S Scardapane L Guzmán J Piezzi RS 《The Anatomical record》2000,258(3):252-261
Randomly distributed extracellular colloidal accumulations were observed in the pars distalis of viscacha (Lagostomus maximus maximus). They were preferentially located in the peripheral zone of the gland and showed variability in shape and size. Two different types of colloidal accumulations were found by electron microscopy: 1) those surrounded by nongranulated follicular cells that correspond to characteristic follicles, and 2) those surrounded by granulated cells. In the follicles lined by nongranulated follicular cells, long, prominent microvilli and cytoplasmic processes protruded into the lumen. The frequency of these accumulations varies during the year in adult male animals, showing an increase in number during summer and a decrease during winter. The lowest value was registered in August (winter). The mean follicular diameter did not vary seasonally. The number of colloidal accumulations did not vary seasonally in adult female viscachas, but a significant difference in the mean follicular diameter between pregnant and non-pregnant females was observed. Pituitaries of immature animals contain fewer colloidal accumulations than those of adults. In fetuses, these accumulations were absent. The administration of melatonin provoked a decrease in the number of these structures. The numeric changes of the colloidal accumulations observed in this study are associated with: 1) the seasonal reproductive activity in adult males, and 2) the reproductive condition, body weight and sexual maturity in males and females. The fact that melatonin administration decreases the population of colloidal accumulations in males suggests participation of the pineal gland in these changes. 相似文献
994.
Sánchez-Seco MP Rosario D Domingo C Hernández L Valdés K Guzmán MG Tenorio A 《Journal of virological methods》2005,126(1-2):101-109
Flaviviruses are a widespread and numerous group of arboviruses that can cause serious illness in humans. The continuous and slow spread of certain flaviviruses, such as Dengue viruses, and the recent entry and spread of West Nile virus to the American continent, point to the need to control these infections. This control requires the use of suitable techniques for diagnostic and surveillance programmes. A generic RT-nested-PCR that is, theoretically, able to detect each member of the group has been designed. The identification of the detected virus is carried out by sequencing. The introduction of an internal control would reduce the number of false negative results and could be used to quantify the viral load in clinical samples where the method works well. 相似文献
995.
A mentally retarded young female having 47 chromosomes with a triple X karotype produced a child with Turner's syndrome associated with mental defeciency. To our knowledge this is the first example of a triple X female giving birth to a child with Turner's syndrome. 相似文献
996.
G. Kour�� M. G. Guzm��n L. Vald��s I. Carbonel D. del Rosario S. Vazquez J. Lafert�� J. Delgado M. V. Cabrera 《Emerging infectious diseases》1998,4(1):89-92
After 15 years of absence, dengue reemerged in the municipality of Santiago de Cuba because of increasing migration to the area by people from disease-endemic regions, a high level of vector infestation, and the breakdown of eradication measures. The 1997 epidemic was detected early through an active surveillance system. Of 2,946 laboratory-confirmed cases, 205 were dengue hemorrhagic fever, and 12 were fatal. No deaths were reported in persons under 16 years of age. Now the epidemic is fully controlled. 相似文献
997.
The role of priority programmes in the provision of health services in the state of Oaxaca, Mexico 总被引:2,自引:0,他引:2
Nigenda G Orozco E Guzmán M Mora G Lockett L Pacheco C 《Health policy (Amsterdam, Netherlands)》1998,43(2):125-139
An assessment of the performance of five priority health programmes (basic sanitation, tuberculosis, vaccination, acute respiratory infections and acute diarrheal diseases) was carried out using ethnographic techniques in the region of La Ca?ada in the state of Oaxaca, Mexico. The region presents a large percentage of Indian and peasant population living in extreme poverty and health care is mainly provided by the Ministry of Health. Both characteristics of the population and the health services are used to analyze the performance of the programmes. With access to abundant resources, vaccination and diarrheal disease programmes have been highly successful in involving the population and achieving their operative targets. Consequently this capacity to concentrate resources results in a lack of resources for other programmes. Despite partial successes, all programmes face serious operational difficulties demonstrating, in turn, the lack of capacity of health services to respond to the specific demands of local populations. The information presented is relevant for the discussion of selective versus comprehensive PHC. 相似文献
998.
Avilés A Guzmán R García EL Díaz-Maqueo JC 《Cancer biotherapy & radiopharmaceuticals》1996,11(1):21-24
To assess the efficacy and toxicity of biological modifiers in combination etetrinate, 0.8 mg/kg/day, po and interferon alfa 2a 9.0 MU, three times at week) in the treatment of refractory cutaneous T-cell lymphoma (CTLC) we began a clinical study on 12 heavily treated patients. After 1 year on treatment 10/12 patients (83%) achieved complete response. Two patients were considered failures with disease progression. After a median follow-up of 3 years, seven patients (56%) remained in complete remission. Toxicity was mild. All patients received 93% of the planned dose of etetrinate and interferon. We feel that biological modifiers, as etetrinate and interferons, are agents with limited hematological toxicity even in higher doses. The combination of two agents, with different mechanisms of action, could improve the outcome in patients with refractory CTCL. Controlled trials are necessary to define the roles of this type of therapy as first line of treatment. 相似文献
999.
In previous work, we demonstrated that dehydroleucodine (DhL), a lactone isolated from Artemisia douglasiana Besser, prevents gastroduodenal damage induced by absolute ethanol (EtOH). The present study examined the effects of DhL - applied alone or before EtOH - on gastroduodenal cells containing 5-hydroxytryptamine (5-HT), to clarify the mechanism of action of the drug. Mice were divided into four groups: (I) control; (II) DhL; (III) EtOH, and (IV) DhL + EtOH. Stomachs and duodena were studied by immunohistochemistry and image analysis. EtOH decreased the immunopositive cell number and the area occupied by these cells. This effect was prevented by DhL. DhL alone did not affect the gastric immunopositive cell number and area. Duodena treated only with DhL exhibited a reduction of immunopositive cell number, but no change in area was observed. We propose that the drug probably inhibits the release of the inflammatory mediator 5-HT from endocrine cells, acting as a 'cell stabilizer' in response to injury. 相似文献
1000.
G García M Arango A B Pérez L Fonte B Sierra R Rodríguez-Roche E Aguirre I Fiterre M G Guzmán 《Journal of clinical virology》2006,37(1):53-57
Acute and late convalescent sera (collected at day 5 of disease onset and 1 year later) from dengue fever (DF) and dengue hemorrhagic fever/dengue shock syndrome (DHF/DSS) laboratory confirmed cases, were tested for antibody-dependent cell-mediated cytotoxicity (ADCC) activity using dengue 1 (DENV-1) or dengue 2 (DENV-2) infected cells as target. All patients experienced their first dengue virus (DENV) infection 20 years before. ADCC activity was detected in acute sera from DHF/DSS but not in sera from DF patients. However, 1 year after illness, ADCC activity was observed in all cases. This preliminary report represents one of the few studies of ADCC in dengue patients and suggests that ADCC could be implicated in dengue pathogenesis. 相似文献