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排序方式: 共有560条查询结果,搜索用时 218 毫秒
21.
Fernando Sánchez-Patán Rubén Blanco María Ángeles Aller Raquel Anchuelo Fidel San Román Jaime Arias 《Journal of investigative surgery》2013,26(2):135-138
A simplified technique of end-to-side portacaval shunt in the rat is described, consisting in using a microsuture with a looped end. By using this technique, combined with two-step portal vein venotomy, the portal vein and caval vein can be brought closer together in a single movement, with no need for a knot at the start of the shunt. As a result, this modified technique makes it easier and reduces the time required to perform the shunt, without any rise in associated mortality. 相似文献
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José Fidel Baizabal-Carvallo Cecilia Bonnet Joseph Jankovic 《Journal of neural transmission (Vienna, Austria : 1996)》2013,120(11):1579-1589
Movement disorders (MDs), particularly chorea, may be the presenting neurological complication of systemic lupus erythematosus (SLE) and the antiphospholipid syndrome (APS), but the association is not often initially recognized. Current evidence suggests an autoimmune mechanism related to antiphospholipid antibodies in these two conditions, although the antigenic target within the central nervous system has not yet been identified. Based on a comprehensive review of the literature, this article summarizes the current knowledge on MDs in SLE and APS. A high index of suspicion is required to make an early diagnosis and initiate appropriate treatment to provide symptomatic relief and to prevent other systemic complications related to the autoimmune process. 相似文献
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This paper estimates the effect of mother's insurance coverage on neonatal outcomes in Mexico using hospital‐based administrative data. Using an instrumental variable approach to identify the causal effects of health insurance on infant health, we find that mother's insurance coverage has positive impacts on neonatal outcomes. Children born to insured mothers weighed 108 g higher and had reduced probability of low birth weight by 7.5 percentage points. These effects appear to be stronger for mothers with higher levels of education and in municipalities with a higher development index. Findings indicate that expanding insurance coverage could be helpful in improving neonatal outcomes in resource‐constrained countries. 相似文献
26.
Israel Camacho‐Abrego Gullermina Tellez‐Merlo Angel I. Melo Antonio Rodríguez‐Moreno Linda Garcés Fidel De La Cruz Sergio Zamudio Gonzalo Flores 《Synapse (New York, N.Y.)》2014,68(3):114-126
Several studies in rodents have suggested the inactivation of the subthalamic nucleus (STN) as an alternative strategy to Parkinson's disease (PD) treatment. The STN is part of the basal ganglia and plays an important role in the motor function; however, recent data suggest that this structure has a critical role in the cognitive function of the limbic system. The STN receives direct projection from the prefrontal cortex (PFC), structure interconnected with the hippocampus and both structures send excitatory projections to the nucleus accumbens (NAcc). Here, we determined whether and which changes occurred 4 weeks after a STN lesion in the dendritic morphology of pyramidal neurons of the layers 3 and 5 of the PFC and basolateral amygdala, neurons of the ventral hippocampus, and the medium spiny neurons of the NAcc and caudate‐putamen. Dendritic morphology was measured using the Golgi‐Cox procedure followed by Sholl analysis. We also evaluated the effects of STN lesion on locomotor behavior assessed by an open field test, social interaction, acoustic startle response, prepulse inhibition, and locomotor activity induced by a novel environment and amphetamine. We found that STN damage induced a deficit in locomotion measured by open field test with neuronal hypertrophy in PFC (layer 5) and reduced spinogenesis in CA1 ventral hippocampus and PFC (layer 3). Taken together, these data suggest that the behavioral and morphological effects of STN lesion are, at least partially, mediated by limbic subregions with possible consequences for cognitive‐related behaviors observed in PD treatment. Synapse 68:114–126, 2014. © 2013 Wiley Periodicals, Inc. 相似文献
27.
Rafael A. Casuso Emilio Martínez-López Fidel Hita-Contreras Irene Ruiz-Cazalilla David Cruz-Díaz Antonio Martínez-Amat 《Journal of Sports Science and Medicine》2014,13(4):958-963
The aim of the present study is to test the hypothesis that sprint swimming performance is enhanced by in-water passive recovery (IN) after sprint swimming bouts in well-trained adolescent swimmers. Using a randomized crossover study design, twelve well-trained adolescent swimmers performed two tests at the swimming pool after preliminary testing. They performed 5 bouts of 100m all-out swimming separated by 5 minutes of passive rest. Their individual in- or out-of-water passive recovery condition was randomized on the first day. In their second visit to the swimming pool the opposite recovery condition was indicated. More than 60% of the subjects which rested in-water were faster in the 5th bout when compared to the OUT group. However, no significant differences were found in blood lactate when IN and OUT were compared. After the first bout peak heart rate (HR peak) was lower in subsequent bouts for IN recovery when compared with OUT (p < 0.001). Thus, coaches and researchers should take into account that IN passive recovery may decrease loss of performance and diminish HR peak during sprint swimming bouts. This is particularly important given the use that many coaches give to HR as a tool in daily training.
Key points
- In-water passive recovery minimizes the loss of performance during high intensity swimming
- Maximal HR is significantly reduced by in-water recovery
- Coaches should take this information into account when using HR to control swimming intensity
- Future research should study long-term effects induced by in-water passive recovery
28.
Garrett Lee M.D. Anthony N. DeMaria M.D. Ezra A. Amsterdam M.D. Fidel Realyvasquez M.D. Juan Angel M.D. Stephen Morrison M.D. Dean T. Mason M.D. 《The American journal of medicine》1976,60(7):949-955
The cardiocirculatory effects of the commonly used parenteral analgesics, morphine sulfate 15 mg, meperidine hydrochloride 100 mg and pentazocine 60 mg, each administered intravenously, were compared in 12 patients with acute myocardial infarction during cardiac catheterization and by echocardiogram. No untoward hemodynamic effects occurred following the administration of morphine or meperidine. In contrast, pentazocine produced significant (p < 0.01 to < 0.05) increases in systemic and pulmonary arterial pressures, left ventricular filling pressure, systemic vascular resistance, and systolic and diastolic dimensions; and decreases in left ventricular ejection fraction and mean velocity of circumferential fiber shortening. These deleterious actions of pentazocine appeared due to peripheral vasoconstriction and negative inotropic properties. Further, pentazocine-induced increases in left ventricular preload and afterload increased myocardial oxygen demands. Since this study demonstrates that pentazocine is hazardous in myocardial infarction, morphine and meperidine are the preferred analgesics in this condition. 相似文献
29.
Short-term antigen presentation and single clonal burst limit the magnitude of the CD8(+) T cell responses to malaria liver stages 总被引:4,自引:0,他引:4
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Hafalla JC Sano G Carvalho LH Morrot A Zavala F 《Proceedings of the National Academy of Sciences of the United States of America》2002,99(18):11819-11824
Malaria sporozoites induce swift activation of antigen-specific CD8(+) T cells that inhibit the intracellular development of liver-stage parasites. The length of time of functional in vivo antigen presentation, estimated by monitoring the activation of antigen-specific CD8(+) T cells, is of short duration, with maximum T cell activation occurring within the first 8 h after immunization and lasting approximately 48 h. Although the magnitude of the CD8(+) T cell response closely correlates with the number of parasites used for immunization, increasing the time of antigen presentation by daily immunizations does not enhance the magnitude of this response. Thus, once a primary clonal burst is established, the CD8(+) T cell response becomes refractory or unresponsive to further antigenic stimulation. These findings strongly suggest that the most efficient strategy for the induction of primary CD8(+) T cell responses is the delivery of a maximal amount of antigen in a single dose, thereby ensuring a clonal burst that involves the largest number of precursors to become memory cells. 相似文献
30.
Long‐term risk of adult overweight and obesity among achalasia patients who underwent Heller Myotomy