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91.
The ultrastructure and cytochemistry of merogonial, gamogonial, and early sporogonial stages of Eimeria sparis in the intestine of Sparus aurata were studied. Mature stages showed the typical pellicle, which was lost in some transitional stages. An apparent unit membrane
was seen in some immature stages. A parasitophorous vacuole, sometimes with membrane vesicular invaginations, was usually
observed. We propose that the stages located over the epithelium and the so-called epicellular stages be termed supraepithelial
stages. Endomerogony was observed in intraepithelial and supraepithelial positions. Intraepithelial stages apparently starting
ectomerogony were also detected. Electron-dense granules similar to wall-forming-like bodies of types 1 and 2 were observed.
Microgametes exhibited two flagella. Cytochemistry study revealed scarce polysaccharides, if any, in merogonial stages and
in microgamonts. The occurrence of polysaccharides and amylopectin granules increased progressively in macrogamonts, macrogametes,
zygotes, and early oocysts. Lipidic droplets were scarce or absent in merogonial stages and abundant in maturing macrogamonts.
Some glycoproteins were demonstrated in certain merogonial stages.
Received: 30 January 1996 / Accepted: 12 August 1996 相似文献
92.
A mathematical model of the feto-placental circulation which describes the development of the placental vasculature throughout pregnancy on the basis of simple assumptions is used to simulate some abnormalities of the villous vascular tree which may affect the values of Doppler indices. In normal cases, the model shows a decreasing trend of the pulsatility index (PI) throughout pregnancy which is comparable to that observed in vivo. When a pathological interruption of the villous growth is simulated, the PI does not decrease any further, unless the input pressure keeps increasing. When various degrees of obliteration of the villous tree are simulated, either through an occlusive process or a reduction of the lumen of the vessels, the PI values increase and the volume flow decreases to a greater extent. The data predicted by the model are compared to those obtained in clinical studies and in experimental animal models. 相似文献
93.
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
94.
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
95.
A Novelli E Periti G B Massi R Masi T Mazzei P Periti 《Journal of chemotherapy (Florence, Italy)》1991,3(1):23-27
Fourteen women, five with normal cervicovaginal mucosa (Group 1), five with cervical carcinoma (Group 2) and four with relapsing vulvovaginal candidiasis (Group 3) were enrolled and completed this open clinical trial. Each subject received a single dose of 1.82 +/- 0.3 g on average of vaginal paste (for ovules) containing about 1000 mg of 3H-fenticonazole nitrate (266 microCi). Twelve hours after vaginal administration, the paste was removed by vaginal washing. Blood, urine and stool samples were collected at specified time intervals for five days. Plasma, urine, stools and all used material in contact with the paste were assayed for radioactivity. No measurable levels of radioactivity were detected in plasma of subjects of Groups 1 and 3 while in 4 of the 5 subjects with cervical carcinoma (Group 2) fenticonazole was detected during the 24 h after administration with a peak level at about 8 hours. For a period of 5 days, 0.4-1.5% of the dose on average was recovered from urine, and 0.18-0.32% from feces. Based on the excretion data, the extent of vaginal absorption of fenticonazole nitrate in women with vulvovaginal candidiasis was 1.81 +/- 0.57% of the dose, while in women with normal cervicovaginal mucosa it accounted for 0.58 +/- 0.28% of the administered dose. In patients with cervical carcinoma, absorption was 1.12 +/- 0.53%. The maximum amount absorbed corresponds to an exposure of about 0.4 mg/kg of fenticonazole nitrate (for a subject weighing 50 kg). Consequently, the vaginal administration of one ovule containing 1000 mg of fenticonazole nitrate seems to be devoid of risk for patients. 相似文献
96.
M Ballester D Obrador I Carrió C Moya J M Augè R Bordes V Martí I Bosch L Bernà-Roqueta M Estorch 《Circulation》1992,85(1):61-68
BACKGROUND. Detection and treatment for rejection after transplantation are based on the identification of myocyte damage upon endomyocardial biopsy. Noninvasive detection of such damage is possible with 111In-labeled monoclonal antimyosin antibodies (MAA). Although the presence and degree of MAA uptake parallels the rejection activity detected by biopsy, the relation between the degree of uptake and the occurrence of severe rejection-related complications has not been previously assessed. METHODS AND RESULTS. Two hundred forty-seven MAA studies were performed coinciding with biopsies in 52 patients 1-71 months after transplantation. A heart-to-lung ratio (HLR) was used as a measure of relative MAA uptake, with an HLR of 1.55 discriminating normal from abnormal studies. Of the 247 antimyosin studies, 149 coincided with absent, 38 with mild, and 60 with moderate rejection at biopsy. HLR was 1.68 +/- 0.27, 1.79 +/- 0.22, and 1.91 +/- 0.33 in the three biopsy groups, respectively (p less than 0.0001). Two hundred thirty-eight of 247 antimyosin studies coexisted with absent rejection-related complications; in nine of 247 patients, such complications were detected (five congestive heart failure episodes due to rejection and four episodes of vascular occlusion, which resulted in five deaths), and mean HLR was 1.74 +/- 0.3 and 2.1 +/- 0.16 in the two groups, respectively (p less than 0.0001). No complications were noted in 193 studies of patients with HLR of less than 2.00, whereas in nine of 45 with HRL of 2.00 or greater, complications occurred (p less than 0.0001). None of the 23 patients prospectively followed since surgery who had a gradual decrease in MAA uptake during the first 3 months showed rejection-related complications, whereas persistent uptake was associated with complications in five of nine patients (p less than 0.001). CONCLUSIONS. No rejection-related complications are seen coinciding with HLR of less than 2.00, whereas patients who have complications have an HLR of more than 2.00. The early 3-month pattern of decreasing MAA uptake is associated with a clinical course free of rejection-related complications, whereas a persistent pattern is a signal of the possibility of such complications. 相似文献
97.
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
98.
P Ibern Regàs 《Gaceta sanitaria / S.E.S.P.A.S》1992,6(31):176-185
The satisfaction analysis in health services has been object of rising interest recently. The different instruments of measurement known show the diversity of conceptualism, range of applications and methodologies. The article revises selectively and not exhaustively different instruments as well as the approximations to the concept of satisfaction from the marketing disciplines and the investigations in health services. Special emphasis is dedicated to the analysis of satisfaction in hospital services and the use of questionnaires for its measurement. 相似文献
99.
Nitrate administration to enhance the detection of myocardial viability by technetium-99m tetrofosmin single-photon emission tomography 总被引:3,自引:1,他引:2
Albert Flotats Ignasi Carrió Montserrat Estorch Lluís Bernà Ana M. Catafau Carina Mart Manel Ballester 《European journal of nuclear medicine and molecular imaging》1997,24(7):767-773
A comparison was performed between technetium-99m tetrofosmin myocardial perfusion tomography at baseline and after nitrate administration, using a 2-day protocol, and rest-reinjection thallium-201 single-photon emission tomography (SPET) studies in order to assess whether nitrates enhance the detection of viable myocardium with99mTc-tetrofosmin. Fifteen patients with coronary artery disease, previous myocardial infarction and a left ventricular ejection fraction <40% underwent201T1 rest-injection and99mTc-tetrofosmin. baseline-postnitroglycerin (0.4 mg sublingually) SPET studies, within 48 h. Tomograms based on the three spatial planes were divided into 15 segments and regional tracer uptake was quantitatively analysed. Viability was defined as presence of tracer uptake >50% of peak activity on baseline studies or after reversibility. The percentage of peak activity of99mTc-tetrofosmin at baseline correlated with that of 201T1 (r=0.82,P <0.001). On baseline99mTc-tetrofosmin studies, 73 of the 225 segments that were analysed had <50% of peal. activity. Fifteen percent of these segments showed reversibility after nitrate administration, with an increase in99mTc-tetrofosmin uptake from 40%±9% to 57%±9% of peak activity (P=0.003). All reversible segments after nitrate administration had viability criteria on201Tl studies, but 20 segments that were non-viable on99mTc-tetrofosmin. studies were viable on201Tl studies. Using a threshold value of >40% of peak activity, only seven segments remained non-viable on99mTc-tetrofosmin studies. Overall agreement between99mTc-tetrofosmin with nitrates and201Tl-reinjection regarding the presence of myocardial viability was 90%. Detection of myocardial viability with99mTc-tetrofosmin. was enhanced after nitrate administration, correlating with viability criteria observed on thallium studies. 相似文献
100.
Power spectral analysis of heart-rate variations improves assessment of diabetic cardiac autonomic neuropathy. 总被引:10,自引:0,他引:10
F Bellavere I Balzani G De Masi M Carraro P Carenza C Cobelli K Thomaseth 《Diabetes》1992,41(5):633-640
Power spectral analysis (PSA) of heart-rate variations has recently proved a useful tool in evaluating cardiovascular autonomic activity. It offers the possibility of examining both the functioning of parasympathetic and sympathetic pathways through breakdown into two frequency bands, and of their effects on heart-rate cyclic variability. We applied an autoregressive model for PSA to study overall autonomic tone in 20 male age-matched control subjects and 53 insulin-dependent (type I) diabetic subjects, subdivided into three groups of 20, 15, and 18, each group presenting different degrees of autonomic involvement. We found that: 1) power spectrum density (PSD) values at high-frequency bands (parasympathetic dependent) were similar in diabetic subjects without cardiac autonomic neuropathy (CAN) and in control subjects, but differed significantly from diabetic subjects with mild CAN and severe CAN, both standing and lying; 2) PSD values at low frequency (mainly sympathetic dependent) were similar, or slightly different, in diabetic subjects without CAN and in control subjects, but differed significantly from diabetic subjects with mild and severe CAN, both standing and lying; 3) as an expression of parasympathetic versus sympathetic coherence, correlations, both standing and lying, existed between PSD values at low- and high-frequency bands in control and diabetic subjects without CAN, but not in diabetic subjects with CAN; and 4) different degrees of correlation characterized the PSD values of high and low frequencies versus traditional cardiovascular test values in the diabetic subjects. The best correlation was between PSD low-frequency values and the lying-to-standing maneuver.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献