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131.
The sequential changes observed during the mycelium to yeast transformation in Paracoccidioides brasiliensis were studied microscopically. The mycelial elements produced terminal and intercalary swellings which, later on, became chlamydospore-like structures. These increased in size, acquired a double contour and, finally, gave rise to multiple budding cells. Transformation was asynchronous. During the observation period, multiple budding cells and chlamydospores remained attached to the parent mycelium. 相似文献
132.
A Restrepo 《Sabouraudia》1985,23(5):323-334
Some aspects pertaining to the ecology of the dimorphic fungus, Paracoccidioides brasiliensis, are reviewed. The available facts concerning the interactions among the only known host (man), the environment (limited to certain Latin-American countries) and the parasite (with an unknown habitat), are analysed. Efforts are made to detect clue circumstances which may lead to discovery of the fungus micro-niche. An analysis of P. brasiliensis mycelial form reveals that such a form has the required capabilities to be the natural infectious form. Its requirements for a moist environment in vitro as well as the high relative humidity predominating in the heart of the endemic areas point towards the possibility of an aquatic--or at least, an extremely humid--habitat for P. brasiliensis. 相似文献
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134.
Background
Experimental studies support an important role for endothelial nitric oxide synthase (eNOS) in the regulation of angiogenesis. In humans, a common polymorphism exists in the eNOS gene that results in the conversion of glutamate to aspartate for codon 298. In vitro and in vivo studies have suggested a decreased NOS activity in patients with the Asp298 variant. We hypothesized that a genetic-mediated decreased eNOS activity may limit collateral development in patients with chronic coronary occlusions.Methods
We selected 291 consecutive patients who underwent coronary angiography and who had at least one chronic (>15 days) total coronary occlusion. Collateral development was graded angiographically using two different methods: the collateral flow grade and the recipient filling grade. Genomic DNA was extracted from white blood cells and genotyping was performed using previously published techniques.Results
Collateral development was lower in patients carrying the Asp298 variant than in Glu-Glu homozygotes (collateral flow grade: 2.64 ± 0.08 and 2.89 ± 0.08, respectively, p = 0.04; recipient filling grade: 3.00 ± 0.08 and 3.24 ± 0.07, respectively, p = 0.04). By multivariable analysis, three variables were independently associated with the collateral flow grade: female gender, smoking, and the Asp298 variant (p = 0.03) while the Asp298 variant was the sole variable independently associated with the recipient filling grade (p = 0.03).Conclusion
Collateral development is lower in patients with the Asp298 variant. This may be explained by the decreased NOS activity in patients with the Asp298 variant. Further studies will have to determine whether increasing eNOS activity in humans is associated with coronary collateral development. 相似文献135.
Guhl F Restrepo M Angulo VM Antunes CM Campbell-Lendrum D Davies CR 《Trends in parasitology》2005,21(6):259-262
In recent years, there has been a revitalization of large-scale programmes to control parasitic disease in developing countries. In 1997, the Governments of Colombia, Venezuela, Ecuador and Peru committed themselves to replicate the cost-effective elimination of Trypanosoma cruzi transmission achieved in the Southern Cone by using insecticides against the domestic triatomine vectors (in combination with blood-bank screening). Central American Governments launched a complementary initiative. All plan to interrupt vectorial transmission throughout the region by 2010 but specific targets are decided nationally. In this article, we highlight the novel approach taken by the Colombian Government for determining the geographic distribution of Chagas disease risk to select where to intervene first. 相似文献
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López JA Cuartas MC Molina OL Restrepo AC Maya CY Jaramillo S 《Biomédica : revista del Instituto Nacional de Salud》2004,24(3):318-323
The improvement of microbiological information processing in clinical laboratories depends on retention of information concerning who, what, when, how, and why each process was performed, the implementation of quality control procedures, and finally, its evaluation. The four objectives to be addressed are as follows: (1) to improve the collection of information concerned with microbiological processes, (2) to evaluate results of implemented strategies, (3) to offer a model data base to be used in research projects, and (4) to propose an evaluation model for comparative studies. To do this, microbiological cultures were collected from hospitalized patients from June 1997 to June 2003. Data for the analytical matrix were obtained from lab requests, medical history and the microbiological data. Statistical analyses were performed in Epi-Info 6. The laboratory records for 46,072 microbiological cultures were analyzed. Completion levels in data collection were compared between years 1997 and 2003. Samples from 1997 and 2003 showed 11% and 99% of the request forms specifically requesting microbiological culture, 11% and 99% were completed in 1997 and 2003, respectively. For the same years, 9% and 85% specifically stated the time of the request. Ten percent and 68%, respectively, provided complete information. Zero and 83% respectively stated who had collected the sample. Zero and 77%, respectively, specified the time of sample collection. Forms containing all relevent microbiological data were most complete with 78% and 96%, respectively. A database with 44 variables related to microbiological processes was created. In conclusion, improvement of microbiological data processing depends not only on the method of collection and completion of recorded information, but also on constant quality control and evaluation. 相似文献
139.
Pineda-Tamayo R Arcila G Restrepo P Anaya JM 《Biomédica : revista del Instituto Nacional de Salud》2004,24(4):366-374
The causes of admission and the distribution of direct medical costs were examined to establish the clinical predictors of high hospitalization costs in patients with rheumatoid arthritis. This retrospective study included all rheumatoid arthritis patients who were hospitalized in the Clínica Universitaria Bolivariana in Medellín, Colombia, between January 1999 and June 2003. Data were obtained from the medical records and from the hospital statistical section using a cost-analysis spreadsheet. A total of 41 patients were hospitalized 62 times (0.34 hospitalization per patient per year). Disease activity was the most important cause of admission (60%), followed by surgery (18%), and infection (10%). In 30 (48%) hospitalizations, at least one comorbidity was recorded, with cardiovascular disease being the most frequent (32%). The mean length of stay per patient was 5+/-6 days. The mean total cost was 1,277 US dollars, and the mean cost per day of hospitalization was 235 US dollars. Medications represented 54% of the total cost, whereas that representing medical care was only 3%. Variance analysis disclosed cardiovascular disease as the most important determinant of high costs (p<0.01). In conclusion, the direct costs for inpatients with rheumatoid arthritis were considerable, and arose mainly from organic complications. Prevention and treatment of cardiovascular disease are indispensable not only to reduce the economic burden of rheumatoid arthitis, but also to diminish the risk of mortality. These data assist in the estimation of health care resources and in the selection of public health policies for the improvement of patient outcomes. 相似文献
140.