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101.
The effects of clindamycin on polymorphonuclear leukocytes (PMNLs) were evaluated in vitro and in vivo in an experimental model and in immunocompromised patients with and without infection. Chemotaxis, chemiluminescence, and bactericidal capacity were evaluated using PMNLs preincubated with clindamycin in different concentrations. In the three phases of the study, clindamycin at a concentration of 2 mg/L significantly increased PMNL function. In contrast, when higher concentrations were used, PMNL function was not modified and in some cases it was decreased. Our findings suggest that clindamycin, in concentrations of 2 mg/L, positively modifies PMNL function. 相似文献
102.
We studied 12 non-demented PD patients in on state before and 3 months after posteroventral pallidotomy (PVP), in order to evaluate the effects of surgery upon an unconstrained, multijoint skilled movement as well as a single joint, repetitive, ballistic movement. A Selspot II System was used for three-dimensional data acquisition, processing and reconstruction of limb trajectories. Specific wrist kinematic features of spatial accuracy (linearity and planarity), temporal attributes (acceleration and velocity), spatiotemporal relationships (velocity-curvature coupling), and joint kinematic variables (relationships between wrist and elbow velocities and relative arm angle amplitudes) for each cycle of movement were graphically and numerically analysed. QMC was applied to single joint, repetitive, ballistic movements. QMC significantly improved after PVP (P < 0.0006). However, wrist as well as joint kinematic variables of the gestural movements failed to change significantly after PVP. The lack of improvement of the kinematic abnormalities of the gestural movement in PD patients would indicate that they are unrelated to the basic motor deficit; most likely they are the result of a disruption of a complex of sensorimotor integration processes due to abnormal parieto-frontal basal ganglia interaction. 相似文献
103.
Eduardo M. Salinas Jorge Cebada Alberto Valdés Anoland Garateix Abel Aneiros Julio L. Alvarez 《Toxicon》1997,35(12):1699-1709
The effects were studied of a toxin (Bainh) isolated from the secretion of the Caribbean sea anemone Bunodosoma granulifera on electrical and mechanical activities of rat ventricular muscle. The effects on the ionic currents of single rat and dog ventricular cardiomyocytes were studied using the whole-cell recording patch-clamp technique. In the concentration range from 1 to 10 mg/ml, Bainh increased the force of contraction and induced an increase in action potential duration of ventricular multicellular preparations. In single cardiomyocytes, at concentrations up to 10 mg/ml Bainh showed no significant effects on the sodium current. However, at 0.5–1 mg/ml it increased the L-type Ca current (ICaL) by 25–50%. This increase in ICaL was not voltage dependent and was reversible after washout. The transient outward current was not significantly affected by Bainh (1–10 mg/ml). In this concentration range, Bainh markedly (≈75%) increased the inward-going rectifier current, IK1. This effect that was not voltage dependent and was fully reversible upon returning to control solution. It is suggested that these effects on ionic currents could explain the positive inotropic action of Bainh on cardiac multicellular preparations. 相似文献
104.
Gabriel Manjarrez Leticia Manuel-A Rosalio Mercado-C Jorge Hernandez-R 《International journal of developmental neuroscience》2003,21(5):283-289
In this study, we report that 5-HT(1A) receptors are already present in fractions of axonal growth cones, from the normal rat fetal brain (E-17). Also, in utero undernourished (UN) rat pups at birth show a noteworthy enhancement in the B(max) of [3H]5-hydroxytryptamine (5-HT) and [3H]8-hydroxy-(2-N,N-dipropilamin)-tetralin (([3H])8-OH-DPAT), in the brainstem and cerebral cortex up to the second week after birth. Afterwards, there is a significant decrease in the binding of these ligands. [125I]Cyanopindolo binding in the cerebral cortex only showed a decrease in the same period. An elevation of brain serotonin in both regions was also present. These findings together, suggest that the mechanisms of regulation of serotonergic receptors' expression during the period studied, may not depend on the amount of neurotransmitter in the synaptic cleft, because in the early UN brain it would be expected only a lower receptor's density due to the chronic serotonin increase. On this basis, we propose that developmental activation of brain serotonin biosynthesis observed in early UN animals may disrupt the mechanism regulating the expression of 5-HT receptors during development. 相似文献
105.
J M González Santos J L Vallejo J C Sevilla K Abukassem P Garrido E Bastida M Riesgo R Fortuny R Arcas 《Revista espa?ola de cardiología》1991,44(10):639-647
We present here the clinical results with a second-generation porcine bioprosthesis, the Carpentier-Edwards supra-annular valve (CESA). Two-hundred and twenty-two CESA bioprostheses were implanted in 189 patients during a four-year period (from 1984 to 1987), either as an isolated procedure or associated to mitral or tricuspid repair. The mid-term clinical results have been evaluated after a mean follow-up of 3.4 years, being 96% complete. There were 16 in-hospital deaths (8.4%) and 6 late, potentially valve-related, cardiac deaths (1.1% patients/year). Overall, 86.7 +/- 2% of the patients were free from cardiac death at 6 years (95.1 +/- 2% of the patients surviving the operative period). Linearized rates of valve related complications were the following: 1.4% patients/year for thromboembolism (including valve thrombosis), 0.5% patients/year for treatment-related hemorrhage and 0.7% patients/year for endocarditis. We did not found any case of either intrinsic or extrinsic valve failure, unrelated to infection of thrombosis. Two patients were reoperated, one because of valve thrombosis and the other due to prosthetic valve endocarditis (reoperation rate of 0.3% patients/year). When lethal and nonlethal valve-related complications (including in-hospital deaths) were considered all together, 75.8 +/- 8.4% of the patients remained alive and free of morbid events at 6 years. When patients were grouped according to the valve replaced (aortic, mitral and multiple), best results were found with patients submitted to isolated aortic valve replacement. We conclude that the CESA bioprosthesis has an excellent mid-term clinical performance. However, longer follow-up is necessary to know if improvement in valve design and manufacturing results in increased valve durability. 相似文献
106.
G C Santos M R Araujo T C Silveira F A Soares 《Archives of pathology & laboratory medicine》1992,116(11):1152-1154
Increased amounts of brown adipose tissue have been reported to occur in association with several diseases. The objective of the present study was to determine whether brown adipose tissue accumulation is related to nutritional status. Histologic sections of periadrenal tissue prospectively obtained at consecutive autopsies from 366 adults were examined. The cases were separated into three groups: malnourished (101 autopsies), normotrophic (128 autopsies), and obese (137 autopsies), according to the Quetelet index. Of these patients, 89 had brown adipose tissue accumulation, 35 were malnourished, 32 were normotrophic, and 22 were obese. The results showed a correlation between brown adipose tissue and patient nutritional status and a higher brown adipose tissue accumulation in malnourished patients. Cardiovascular disease was the most common type of illness present in the cases with brown adipose tissue accumulation. 相似文献
107.
108.
109.
J. Ignacio Herrero Juan Felipe Lucena Jorge Quiroga Bruno Sangro Fernando Pardo Fernando Rotellar Javier Alvárez-Cienfuegos Jesús Prieto 《American journal of transplantation》2003,3(11):1407-1412
Older age is not considered a contraindication for liver transplantation, but age-related morbidity may be a cause of mortality. Survival and the incidence of the main post-transplant complications were assessed in 111 adult liver transplant recipients. They were divided in two groups according to their age (patients younger than 60 years, n=54; patients older than 60 years, n=57) and both groups were compared. Older patients were more frequently transplanted for hepatitis C (p= 0.03) and hepatocellular carcinoma (p= 0.05) and their liver disease was less advanced (Child-Pugh and MELD scores were significantly lower; p=0.004 and p=0.05, respectively). After transplantation, older patients had a significantly lower survival (p=0.02). Higher age was independently associated with mortality (hazard ratio for each 10-year increase: 2.1; 95% confidence interval: 1.1- 4.0; p=0.02). The incidence of de novo neoplasia and nonskin neoplasia were higher in older patients (p=0.02 and p =0.007, respectively). Malignancy was the cause of death in one patient younger than 60 years and in 12 patients older than 60 years (p =0.002). In multivariate analysis, a higher age and smoking were independently associated with a higher risk of dying of de novo neoplasia. In conclusion, older liver transplant recipients have a significantly lower survival than younger patients. Malignancy is responsible for this decreased survival. 相似文献
110.