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101.
Objective
To describe the scientific production in medical education in Latin America in Scopus, in the period 2011-2015.Methods
Bibliometric cross-sectional study. A search of scientific papers for the period 2011-2015 was carried out in Scopus, using terms related to medical education and specifying that at least one author should be affiliated with a Latin American country. Each paper was reviewed to select original papers that have studied medical education topics. Finally, its features were recorded and analysed using Microsoft Excel 2010.Results
In the period 2011 - 2015, a total of 850 original medical education papers were published with authors from Latin America in Scopus, of which 49.1% had an author from Brazil. The number of publications per year was stationary. The most frequent study population were medical students (54.0%). The most frequent topic was the evaluation of competences (30.7%). Of the papers found, 21.1% were of international collaboration, but there was little (4.1%) collaboration with authors from other Latin American countries.Conclusions
Research in medical education in Latin America in the period 2011-2015 is still deficient and stationary. The main topic was the assessment of competences, while the most frequent studied population were medical students. International collaboration was low, and collaboration among Latin American countries was lower than collaboration with countries outside Latin America. 相似文献102.
Zúñiga MC 《Virus research》2002,88(1-2):17-33
The poxviruses have evolved a diverse array of proteins which serve to subvert innate and adaptive host responses that abort or at least limit viral infections. Myxoma virus and its rabbit host are considered to represent an ideal poxvirus-host system in which to study the effects of these immunomodulatory proteins. Studies of laboratory rabbits (Oryctolagus cuniculus) infected with gene knockout variants of myxoma virus have provided compelling evidence that several myxoma virus gene products contribute to the pathogenic condition known as myxomatosis. However, myxomatosis, which is characterized by skin lesions, systemic immunosuppression, and a high mortality rate, does not occur in the virus' natural South American host, Sylvilogus brasiliensis. Moreover, in Australia where myxoma virus was willfully introduced to control populations of O. cuniculus, myxomatosis-resistant rabbits emerged within a year of myxoma virus introduction into the field. In this review I discuss the characterized immunomodulatory proteins of myxoma virus, their biochemical properties, their pathogenic effects in laboratory rabbits, the role of the host immune system in the susceptibility or resistance to myxomatosis, and the evidence that immunomodulatory genes may have been attenuated during the co-adaptation of myxoma virus and O. cuniculus in Australia. 相似文献
103.
HIV-1 vertical transmission is thought to mainly take place by virus crossing the placental barrier. However, the mechanism by which HIV-1-infects placental cells remains to be elucidated. We have found that purified cytotrophoblasts as well as trophoblastic cell lines are susceptible to infection by different HIV-1 isolates as detected by DNA-PCR and release of infectious virus, although with very low efficiency. Purified trophoblast or trophoblastic cell lines express low levels of chemokine receptors CCR-5 and CXCR-4 but not CD4 on the cell surface. To test if those molecules were used as receptors for HIV-1 infection, placental cells were pretreated with antibodies to CD4, CC-chemokines, C-X-C chemokines. None of those treatments inhibited HIV-1 infection. In contrast, we have found that HIV-1 infection of placental cells was increased in cocultures of infected T-cell blasts and placental cells. More interestingly, antibodies to beta(2) integrins and to LFA-1 were able to significantly block infection of placental cells. Cell surface expression of ICAM-1, an adhesion molecule involved in attachment of leukocytes to placenta, was upregulated in HIV-1-infected placental cells. Placental cells were able to transfer HIV-1 infection to T-cell blasts. This transmission required cell to cell contact and was also inhibited by anti-LFA-1 antibodies. In summary our results suggest that placental trophoblast could be infected by HIV-1 by a mechanism involving T cell to placental contact. Moreover, placental infection enhanced ICAM-1 expression and leukocyte adherence, an event which was required to transfer HIV-1 infection to T cells. This provides an explanation of the virus passing through the placental barrier during in utero HIV-1 vertical transmission. 相似文献
104.
Prevalence of fragilysin gene in Bacteroides fragilis isolates from blood and other extraintestinal samples 总被引:1,自引:0,他引:1 下载免费PDF全文
Foulon I Piérard D Muyldermans G Vandoorslaer K Soetens O Rosseel P Lauwers S 《Journal of clinical microbiology》2003,41(9):4428-4430
Of 166 Bacteroides fragilis isolates, 26.2% of 103 isolates from blood and 20.6% of 63 extraintestinal isolates harbored the fragilysin gene (difference not statistically significant). Clinical characteristics and evolution were comparable in patients with B. fragilis bacteremia with or without this enterotoxin. Fragilysin seems not to be an important virulence factor in B. fragilis disease. 相似文献
105.
Thiols decrease cytokine levels and down-regulate the expression of CD30 on human allergen-specific T helper (Th) 0 and Th2 cells 下载免费PDF全文
Bengtsson A Lundberg M Avila-Cariño J Jacobsson G Holmgren A Scheynius A 《Clinical and experimental immunology》2001,123(3):350-360
The thiol antioxidant N-acetyl- L-cysteine (NAC), known as a precursor of glutathione (GSH), is used in AIDS treatment trials, as a chemoprotectant in cancer chemotherapy and in treatment of chronic bronchitis. In vitro, GSH and NAC are known to enhance T cell proliferation, production of IL-2 and up-regulation of the IL-2 receptor. The 120-kD CD30 surface antigen belongs to the tumour necrosis factor (TNF) receptor superfamily. It is expressed by activated T helper (Th) cells and its expression is sustained in Th2 cells. We have analysed the effect of GSH and NAC on the cytokine profile and CD30 expression on human allergen-specific T cell clones (TCC). TCC were stimulated with anti-CD3 antibodies in the presence of different concentrations of GSH and NAC. Both thiols caused a dose dependent down-regulation of IL-4, IL-5 and IFN-gamma levels in Th0 and Th2 clones, with the most pronounced decrease of IL-4. Furthermore, they down-regulated the surface expression of CD30, and the levels of soluble CD30 (sCD30) in the culture supernatants were decreased. In contrast, the surface expression of CD28 or CD40 ligand (CD40L) was not significantly changed after treatment with 20 m M NAC. These results indicate that GSH and NAC favour a Th1 response by a preferential down-regulation of IL-4. In addition, the expression of CD30 was down regulated by GSH and NAC, suggesting that CD30 expression is dependent on IL-4, or modified by NAC. In the likely event that CD30 and its soluble counterpart prove to contribute to the pathogenesis in Th2 related diseases such as allergy, NAC may be considered as a future therapeutic agent in the treatment of these diseases. 相似文献
106.
Transmission of Pneumocystis carinii DNA from a patient with P. carinii pneumonia to immunocompetent contact health care workers 总被引:1,自引:0,他引:1
Vargas SL Ponce CA Gigliotti F Ulloa AV Prieto S Muñoz MP Hughes WT 《Journal of clinical microbiology》2000,38(4):1536-1538
The transmission of Pneumocystis carinii from person to person was studied by detecting P. carinii-specific DNA in prospectively obtained noninvasive deep-nasal-swab samples from a child with a documented P. carinii pneumonia (PCP), his mother, two contact health care workers, and 30 hospital staff members who did not enter the patient's room (controls). Nested-DNA amplification was done by using oligonucleotide primers designed for the gene encoding the mitochondrial large subunit rRNA of rat P. carinii (P. carinii f. sp. carinii) that amplifies all forms of P. carinii and internal primers specific for human P. carinii (f. sp. hominis). P. carinii f. sp. hominis DNA was detected in samples from the patient and all of his contacts versus none of the 30 hospital staff members. The results, as previously shown in murine models of P. carinii pneumonia, document that person-to-person transmission of P. carinii is possible. This observation suggests that immunocompromised patients not on PCP prophylaxis should not enter the room of a patient with PCP, and it also raises the question as to whether healthy contacts can transmit the disease to immunocompromised patients at risk. 相似文献
107.
Ibáñez L Potau N Enriquez G Marcos MV de Zegher F 《Human reproduction (Oxford, England)》2003,18(8):1565-1569
BACKGROUND: Fetal growth restraint has been associated with FSH hypersecretion in early infancy and in early post-menarche, and with reduced uterine and ovarian size in adolescence. It is unknown whether these reproductive anomalies persist, respectively, into late infancy and into the reproductive age range. METHODS: We report follow-up findings in two age groups of girls. A cohort of infants [n=26; n=10 born appropriate-for-gestational-age (AGA) and n=16 born small-for-gestational-age (SGA)], who had been studied at the age of approximately 4 months, was assessed again at the age of 12 months. A cohort of teenagers (n=28), who had been studied at the age of approximately 14 years, was assessed again at the age of approximately 18 years; this group was complemented by a transversal cohort of similar age (n=19) for a total of 47 young women (n=27 AGA; n=20 SGA). In infants, only serum FSH was measured; adolescents underwent endocrine-metabolic screening, ultrasound assessment of uterine-ovarian size, and evaluation of body composition by dual X-ray absorptiometry. RESULTS: Serum FSH levels were higher in SGA than AGA infant girls at 4 and 12 months, and higher in SGA than AGA adolescents at 14 and 18 years (all P<0.01). Longitudinal ultrasound assessments disclosed a late-adolescent increment of uterine size that was less obvious in SGA than AGA girls. In contrast, ovarian volume remained stable in both subgroups. Compilation of longitudinal and transversal results at 18 years of age corroborated the persistent reduction in the uterine size of SGA girls (by approximately 20%; P<0.005) and in their ovarian volume (by approximately 40%; P<0.0001); moreover, SGA girls displayed not only a persistent elevation of FSH (by approximately 50%; P<0.001), but also a rise of LH and fasting insulin, as well as an excess of abdominal fat (all P<0.01). CONCLUSIONS: The gynaecology of young women born SGA was found to be characterized by hypergonadotrophinaemia and by a reduced uterine and ovarian size. 相似文献
108.
109.
Añez G 《Investigación clínica》2005,46(1):1-3
In November 2004, sponsored by the World Bank, the Venezuelan Foundation of Science, Technology and Innovation (Fonacit) and the Venezuelan Institute of Scientific Research (IVIC), delegates from the different virology research groups of the country, met in Caracas-Venezuela, with the aim to establish the "Venezuelan Virology Network". The symposium entitled "Molecular biology applied to virus of health importance in Venezuela", was divided into three areas, including human and animals viruses related to public health: 1) Dengue, others arboviruses and Hemorrhagic Fevers; 2) diarrhea-related and others veterinary viruses and 3) Hepatitis, HIV and others sexually transmitted viruses. This symposium allowed the delegates to evaluate the current strengths, weaknesses and needs of the different laboratories, becoming evident the necessity of developing collaborative work between the groups that share the same interests or lines of research; and also their need to exchange technical resources, human and bibliographical material and consequently, avoiding the duplication of efforts and the unnecessary cost of resources. One of the main strengths of Venezuelan virology is the presence, in most laboratories, of researchers with studies of fourth level and multidisciplinary teams of work. We aspire to achieve the raised objectives in the event, to the benefit of our virology and even more important, of our people. 相似文献
110.
Antonio López-Beltrán Alfonso S. Calañas Pilar Jimena Alberto L. Escudero Telma R. Campello Manuel Muñoz-Torres Fernando Escobar-Jiménez Rafael E. Carvia F. F. Nogales 《Virchows Archiv : an international journal of pathology》1997,431(2):149-151
Three further cases of mature benign cystic teratomas of the ovary associated with virilization are added to the three previously
reported in the literature. They were found in postmenopausal, obese, diabetic women aged 52, 61, and 67 years. The patients
presented with hirsutism and voice changes and clitoromegaly was present in one. Testosterone and androstenedione levels were
elevated but promptly regressed after removal of the tumours. Histologically, sheets of stromal luteinized cells were found
peripherally at the interface between the neoplasm and ovarian tissue. Luteinization of ovarian stroma induced by an unknown
factor related to diabetes mellitus is the origin of the virilization.
Received: 8 January 1997 / Accepted: 28 February 1997 相似文献