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排序方式: 共有451条查询结果,搜索用时 15 毫秒
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2.
G Bussone L La Mantia E A Parati F Frediani E Lamperti A Boiardi C Peccarisi A M Tortorano M A Viviani 《European neurology》1986,25(4):256-261
A case of cryptococcal meningoencephalitis, as presented by a hypertensive hydrocephalus, is described. To our knowledge, this is the 24th case described in Italy since 1953. The diagnosis was made with ventricular fluid examination: the patient was successfully treated with amphotericin B and 5-fluorocytosine, thus avoiding the risks of surgical treatment of hydrocephalus. Early diagnosis and proper therapy are necessary in order to decrease the high lethality of cryptococcosis. 相似文献
3.
We investigated the effect of sex hormones on the sex-dependent response of rat kidney ornithine decarboxylase (ODC) activity to cadmium (Cd) administration and the involvement of the renin-angiotensin system in mediating stimulation of the liver enzyme by the metal. The response of renal ODC to Cd, which occurs in intact adult males but not in females, is also detectable in prepubertal and castrated males. Upon treatment with 17 beta-estradiol, the basal levels of enzyme activity in intact or castrated adult males were enhanced and Cd administration failed to increase them further. In adult females the kidney enzyme became responsive after ovariectomy. Also, in prepubertal females renal ODC was induced by Cd, and this was prevented by treatment with 17 beta-estradiol. Under the same conditions, changes in the levels of Cd accumulation within the kidney, that might account for variations in the response of ODC activity, did not occur. Cd caused an increase in renin activity starting minutes after its injection. Captopril, which specifically inhibits the conversion of angiotensin I to angiotensin II, prevented completely the induction of liver ODC by this metal; stimulation of the enzyme by Co was not affected by the drug. A similar inhibitory effect was exerted by propranolol. Adrenalectomy had no influence on the response of hepatic ODC to Cd; the decarboxylase was unaffected by aldosterone administration. It is suggested that Cd may induce liver ODC through the increase in angiotensin II following stimulation of renin by the metal. 相似文献
4.
A. S. Pinto M. de Lana B. Bastrenta C. Barnabé V. Quesney S. Noël M. Tibayrenc 《Parasitology research》1998,84(5):348-353
A total of 15 mixtures involving 9 different stocks attributed to the 19/20, 32 and 39 major clonal genotypes of Trypanosoma cruzi were used to infect third-instar nymphs of Triatoma infestans via an artificial feeding device. Three biological parameters were considered: (1) the percentage of infected insects (%II),
(2) the number of flagellates per insect (NFI), and (3) the percentage of trypomastigotes per insect (%DIF). Genetic characterization
by both multilocus enzyme electrophoresis (MLEE) and random amplification of polymorphic DNA (RAPD) indicated that in almost
all cases (87%), mixtures remained present after completion of the whole cycle in the insect vector. Two lines of comparison
were performed: (1) pure clonal genotypes versus corresponding mixed clonal genotypes and (2) the␣actual behavior of mixed
clonal genotypes versus the expected behavior of the theoretical mixture (i.e. the␣arithmetic mean of the results observed
for each of the two clonal genotypes taken separately). Statistical analyses of the variables were made difficult because
of the presence of large standard deviations. Nevertheless, in several cases, mixtures differed significantly from pure clonal
genotypes, and in one case the actual mixture differed significantly from the theoretical mixture. In some cases, interaction
(either potentialization or reciprocal inhibition) could be suspected.
Received: 10 March 1997 / Accepted: 21 September 1997 相似文献
5.
Desmurget M Vindras P Gréa H Viviani P Grafton ST 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》2000,134(3):363-377
Several perceptual studies have shown that the ability to estimate the location of the arm degrades quickly during visual occlusion. To account for this effect, it has been suggested that proprioception drifts when not continuously calibrated by vision. In the present study, we re-evaluated this hypothesis by isolating the proprioceptive component of position sense (i.e., the subjects were forced to rely exclusively on proprioception to locate their hand, which was not the case in earlier studies). Three experiments were conducted. In experiment 1, subjects were required to estimate the location of their unseen right hand, at rest, using a visual spot controlled by the left hand through a joystick. Results showed that the mean accuracy was identical whether the localization task was performed immediately after the positioning of the hand or after a 10-s delay. In experiments 2 and 3, subjects were required to point, without vision of their limb, to visual targets. These two experiments relied on the demonstration that biases in the perception of the initial hand location induced systematic variations of the movement characteristics (initial direction, final accuracy, end-point variability). For these motor tasks, the subjects did not pay attention to the initial hand location, which removed the possible occurrence of confounding cognitive strategies. Results indicated that movement characteristics were, on average, not affected when a 15-s or 20-s delay was introduced between the positioning of the arm at the starting point and the presentation of the target. When considered together, our results suggest that proprioception does not quickly drift in the absence of visual information. The potential origin of the discrepancy between our results and earlier studies is discussed. 相似文献
6.
Telleria J Barnabé C Hide M Bañuls AL Tibayrenc M 《Molecular and biochemical parasitology》2004,135(1):133-141
Inositol is an essential precursor for the formation of glycosyl-phosphatidylinositol (GPI)-anchors found in the majority of surface molecules in trypanosomatids, in addition to its requirement for phoshatidylinositol signal transduction pathways. In Leishmania donovani, high-affinity inositol transport is catalyzed by the active myo-inositol/H+ transporter MIT, which is driven by a proton gradient across the parasite membrane. We have characterized the substrate specificity and pharmacology of L. donovani MIT in vitro and in promastigote cultures. High substrate specificity of myo-inositol transport was shown in competition studies with 14 different monosaccharides and MIT function was unaffected by the structurally similar pentose sugars or hexoses. L-Fucose and D-xylose, both inhibitors of the Na+-dependent inositol transport system in the human host, did not affect MIT transport function in the parasite. Competition studies with eight different inositol isomers revealed that proton bonds between the C-2, C-3 and C-5 hydroxyl groups of myo-inositol and the transporter protein played a critical role for substrate recognition, and the C-3 hydroxyl oxygen appears to act as an electron donor to form an H-bond with a positive charge of the MIT permease. The cytotoxic inositol analogue 3-fluoro-myo-inositol was recognized by MIT with similar affinity as myo-inositol and showed an IC50 value of 42 +/- 8 microM in L. donovani cultures. Finally, substrate affinities of MIT revealed apparent Km values of 84 +/- 8 microM for myo-inositol and 5.4 +/- 0.9 nM for H+, equal pH 8.27 + 0.08, suggesting that the L. donovani myo-inositol/H+ symporter is fully activated at physiological pH in the sandfly midgut or macrophage phagolysosome. We conclude that Leishmania MIT constitutes an attractive target for delivery of cytotoxic inositol analogues and differs significantly from the sodium-coupled myo-inositol transport system of the human host. 相似文献
7.
Viviani MA 《International journal of antimicrobial agents》1996,6(3):169-173
In the last decade, largely due to the increasing number of immunocompromised patients, particularly those with AIDS, there has been a dramatic increase in the incidence of cryptococcosis. The majority of human cryptoccoccal infections are caused by C. neoformans. Pulmonary cryptococcosis is the commonest form of infection and meningitis is the most severe, being fatal in most cases. Diagnosis is usually by culture and/or serology. Combined therapy with amphotericin B and flucytosine remains the initial treatment of choice, although a short course of amphotericin B alone followed by high dose fluconazole or itraconazole and the combination of flucytosine with fluconazole or with itraconazole may be effective alternatives. Both azoles, given as single agent maintenance therapy, have been shown to be beneficial as they are more effective and less toxic than the weekly infusion of amphotericin B. Primary prophylaxis with fluconazole has been advocated but problems of resistance are a concern. To date, itraconazole has not been associated with problems of resistance. 相似文献
8.
Thirty-one "top" level european free-climbers (FC) aged 26.1 +/- 4.3 years old, have been measured according to the Health/Carter anthropometric somatotype method, in order to collect data on the morphotypes needed to excel in this not well established sporting activity. The average somatotype for FC revealed to be: mesomorph-ectomorph (2.0 +/- 0.6; 4.0 +/- 0.8; 3.7 +/- 0.9), a facies found in the 54.8% of the performers. With their 8.3% FAT%, they fall inside the category of lean athletes, a well stated feature found in all those activities demanding endurance. When compared with 25 "sedentary" young italians aged 21.7 years old, FC showed to differ significantly in: weight, mean of the sum of the skinfolds, upper arm and geminal circumferences, RPI (reciprocal of the ponderal index), ectomorph component (less than .01). Concluding, their somatotype appeared to be similar to that of athletes whose fatness is lower, to some adolescent performers and to some extra-European cohorts of males living in stressing habitats. 相似文献
9.
The clinical problem of primary and secondary vertebral tumours is encountered with increasing frequency throughout North America as oncologic management protocols evolve and the population continues to age. These lesions can present problems of pain, instability and paralysis. Optimal surgical palliation is often of benefit when more conservative methods have been unsuccessful. Vertebral tumours can be approached either anteriorly or posteriorly. These alternatives have led to the evolution in the clinical community of two "camps" championing their respective approaches. The authors have reviewed the accumulated literature up to December 1988 and have found that anterior approaches offer improved clinical outcome without substantially increased morbidity. 相似文献
10.
Effect of aluminum adjuvants on safety and immunogenicity of Haemophilus influenzae type b-CRM197 conjugate vaccine 总被引:1,自引:0,他引:1
güler Kanra Simonetta Viviani Kadriye Yurdakök Elif Özmert Alessandra Anemona SongüL Yalçn Okan Demiralp Nihan Bilgili Ates Kara Ali BüLent Cengiz Belgin Mutlu Alexandra Baldini Elisa Marchetti Audino Podda 《Pediatrics international》2003,45(3):314-318
OBJECTIVE: The present study was carried out to evaluate the safety and immunogenicity of the Haemophilus influenzae type b-CRM197 (Hib-CRM197) conjugate vaccine in relation to the change of adjuvant from aluminum hydroxide to aluminum phosphate (AlPO4). METHODS: The present study was a clinical phase II, observer-blind, randomized, multicenter, controlled study. Subjects were healthy infants aged 6-12 weeks, eligible for expanded program of immunization (EPI) routine vaccination and admitted to Hacettepe University Department of Social Pediatrics and Gülveren Health Center, Ankara. A total of 520 healthy infants were randomized in a 2:2:1 ratio to receive at either Chiron Hib/AlPO4 vaccine or VaxemHib (aluminum hydroxide adjuvant) vaccine or HibTiter (no adjuvant). Vaccines were administered simultaneously with routine diphtheria, tetanus and pertussis (DTaP) and oral polio vaccine (OPV) vaccines at 2, 4 and 6 months of age. Blood samples for anti-plain polysaccharide (PRP) antibody measurement were collected before the first vaccination and 1 month after the last vaccination. After each vaccination parents filled out a diary for 7 days. RESULTS: Out of 520 subjects enrolled, 514 received three doses and were included for safety analysis. Local and systemic reactions occurred with low and similar frequencies in all groups. Only erythema was more common in Chiron Hib/AlPO4 vaccine (19, 10, 11% in Chiron Hib/AlPO4, VaxemHib and HibTiter, respectively, P < 0.05). Nine serious adverse events were reported in seven cases of which none were related to vaccines. A total of 504 subjects were included in the immunogenicity analysis. The three vaccines were highly immunogenic and equivalent in terms of percentage of acquisition of long-term protective levels. The anti-PRP geometric mean titers were 9.9, 8.3 and 5.14 micro g/mL, respectively (P < 0.05). CONCLUSIONS: The use of aluminum compounds adjuvants in Hib-CRM197 conjugate vaccines does not impact the safety profile, while it does increase the magnitude of anti-PRP antibody titers. 相似文献