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2.
Visceral leishmaniasis: another HIV-associated opportunistic infection? Report of eight cases and review of the literature 总被引:5,自引:0,他引:5
J Altés A Salas M Riera M Udina A Galmés J Balanzat A Ballesteros J Buades F Salvá C Villalonga 《AIDS (London, England)》1991,5(2):201-207
Visceral leishmaniasis (VL) is considered an opportunistic infection in immunocompromised patients. We review the clinical, laboratory, and therapeutic data in 63 patients (eight new cases and 55 cases reported in the literature) with Mediterranean VL (kala azar) and HIV-1 infection to determine whether VL should be considered an opportunistic infection in HIV-infected adults. We conclude that: (1) in areas where both leishmaniasis and HIV-1 infection are endemic, VL may be more frequent among HIV-infected adults; (2) in HIV-infected patients, the clinical picture did not differ significantly from classical kala azar, although it often ran a recurrent course, with resistance to antimonial therapy. We propose the inclusion of VL in the IVC-2 subgroup of the Centers for Disease Control (CDC) clinical classification of HIV-1 infection while prospective and larger studies further define whether there are clinical presentations that could justify adding VL to the list of opportunistic infections indicative of AIDS. 相似文献
3.
Different mathematical expressions have been proposed in the literature with the aim to reflect the risk of calcium oxalate urolithiasis. Such expressions, as well as a number of new relationships proposed by us, have been evaluated in 76 patients and 34 normal subjects. Stone-formers were divided into two groups: patients with normal calcium and oxalate excretion and patients with hypercalciuria and/or hyperoxaluria. The results obtained were comparatively evaluated. Several formulae gave some acceptable results, but none of them were excellent. This can be explained by the fact that these discrimination indexes more or less reflect supersaturation and/or inhibition deficit, but none of them reflect promoting factors such as heterogeneous nucleation and/or aggregation capacity. 相似文献
4.
酞丁安对映体合成及其抗单纯疱疹病毒活性评价 总被引:1,自引:0,他引:1
酞丁安(3-酞酰亚胺-2-氧-正丁醛双缩氨硫脲,TDA)是药物研究所创制的抗病毒新药。为了研究其对映异构体(R),(S)-TDA对病毒活性及毒性是否有差异,并与消旋酞丁安(RS)-TDA的抗病毒活性及毒性进行比较,本文分别用已知构型的(R)-与(S)-丙氨酸为原料,通过缩合等6步反应,得到光学活性的(R)-,(S)-TDA,并与外消旋酞丁安比较其抗病毒活性及毒性。三者的抗单纯疱疹病毒活性与对细胞的毒性差别不大,说明消旋酞丁安临床使用是安全有效的。 相似文献
5.
M Avellanet RM Mirapeix D Escudero C Riera JM Domenech-Mateu 《Surgical and radiologic anatomy : SRA》1996,18(4):271-273
Summary We present a case with a characteristic magnetic resonance image (MRI) of bilateral open-lipped schizencephaly and atypical clinical presentation. The patient is still alive and in good health in her forties, she has never presented seizures, and although the motor dysfunction is well correlated with cerebral lobe involvement, neurobehavioral dysfunction is not proportional to the MR image of the cerebral malformation.
Un cas inhabituel de schizencéphalie bilatérale
Résumé Nous présentons un cas de schizencéphalie bilatérale ouverte caractérisé par une présentation clinique atypique et une imagerie par résonance magnétique nucléaire caractéristique. La patiente est encore vivante, en bonne santé, à plus de 40 ans, elle n'a jamais présenté de crise comitiale et, bien que les troubles moteurs soient bien corrélés aux altérations cérébrales, les troubles neuro-comportementaux ne sont pas proportionnels aux images IRM de cette malformation cérébrale.相似文献
6.
P. Valdés J. Bosch R. Grave J. Hernandez J. Riera R. Pascual R. Biscay 《Brain topography》1992,4(4):309-319
The structure of the normal resting EEG crosspectrum SVV(omega) is analyzed using complex multivariate statistics. Exploratory data analysis with Principal Component Analysis (PCA) is followed by hypothesis testing and computer simulations related to possible neural generators. The SVV(omega) of 211 normal individuals (ages 5 to 97) may be decomposed into two types of processes: the xi process with spatial isotropicity reflecting diffuse, correlated cortical generators with radial symmetry, and processes that seem to be generated by more spatially concentrated, correlated sources. The latter are reflected as spectral peaks such as the process. The eigenvectors of the xi process are the Spherical Harmonic Functions which explains the recurring pattern of maps characteristic of the spatial PCA of qEEG data. A new method for estimating sources in the frequency domain which fits dipoles to the whole crosspectrum is applied to explain the characteristics of the localized sources. 相似文献
7.
Payeras A Martinez P Milà J Riera M Pareja A Casal J Matamoros N 《Clinical and experimental immunology》2002,130(2):271-278
The aim of the study was to determine possible factors related to the risk of developing recurrent bacterial respiratory tract infections in HIV-1-infected patients, regardless of the degree of immune cellular impairment. Thirty-three HIV-1 seropositive patients with previous repetitive bacterial respiratory tract infections (case group), 33 HIV-1 seropositive controls (matched by CD4-cell counts) without these antecedents and 27 healthy controls were studied before and after administration of pneumococcal and Haemophilus influenzae type b vaccines. Clinical or toxicological variables, cutaneous tests, complement factors, beta2-microglobulin, serum IgM, IgA, IgG and subclasses, specific antibodies (IgG, IgG2, IgA) against pneumococcal vaccine and polyribosylribitol phosphate (PRP), their avidity, opsonophagocytosis and IgG(2)m and Fc(gamma)RIIa allotypes were determined. A history of drug abuse (P = 0.001), less likelihood of receiving high activity antiretroviral treatment high activity antiretroviral treatment (HAART) (P = 0.01), higher levels of HIV-1 viral load (P < 0.05), serum IgG (P < 0.01) and beta2-microglobulin (P < 0.01) were observed in the case group. Also, a lower increase in specific antibodies to pneumococcal vaccine and PRP was demonstrated in the cases in comparison with the two control groups. No differences were observed in the avidity of antibodies, opsonophagocytic capacity or IgG(2)m and Fc(gamma)RIIa allotypes between the three groups. These data indicate that vaccination strategies against encapsulated bacteria can be unsuccessful in the HIV-1-infected patients presenting repetitive bacterial respiratory tract infections if behavioural aspects or measures to improve adherence to HAART therapies are not considered. 相似文献
8.
Cytomegalovirus (CMV) replication in non-proliferating cells requires the coordinated expression of the host enzymes responsible for deoxyribonucleotide synthesis. Thymidylate synthase (TS) is an essential cellular enzyme that catalyzes de novo synthesis of thymidylic acid (dTMP). In this report we show that murine CMV (MCMV) replication and DNA synthesis are inhibited in quiescent 3T6 fibroblasts by raltitrexed, a quinazoline-based folate analog that specifically inhibits TS. This antiviral activity was abrogated in LU3-7 cells, a 3T6 derivative that overproduces TS by about 50-fold. These observations indicate that the anticytomegaloviral activity of raltitrexed is associated with TS inhibition and suggest that cellular TS activity is required for efficient CMV replication in quiescent cells. 相似文献
9.
Detection of Haemophilus influenzae type b antigenuria by Bactigen and Phadebact kits. 总被引:1,自引:2,他引:1 下载免费PDF全文
L Riera 《Journal of clinical microbiology》1985,21(4):638-640
Two commercially available reagents, latex particles (Bactigen) and Staphylococcus aureus suspensions (Phadebact), were compared for the detection of the capsular polyribitol phosphate antigen of Haemophilus influenzae type b in 18 pediatric patients with proven infections due to H. influenzae type b. Whereas both tests nearly equally detected the antigen in the first urine specimens from the patients, the latex test remained positive significantly longer than did the Phadebact test for serial urine specimens. We conclude that the Bactigen test is slightly more sensitive than the Phadebact test for detecting urinary H. influenzae type b antigen. 相似文献
10.
Severe hypoxia decreases oxygen uptake relative to intensity during submaximal graded exercise 总被引:1,自引:0,他引:1
J. Ibañez R. Rama M. Riera M. T. Prats L. Palacios 《European journal of applied physiology》1993,67(1):7-13
Summary The effect of severe acute hypoxia (fractional concentration of inspired oxygen equalled 0.104) was studied in nine male subjects performing an incremental exercise test. For power outputs over 125 W, all the subjects in a state of hypoxia showed a decrease in oxygen consumption (
O2) relative to exercise intensity compared with normoxia (P < 0.05). This would suggest an increased anaerobic metabolism as an energy source during hypoxic exercise. During submaximal exercise, for a given
O2, higher blood lactate concentrations were found in hypoxia than in normoxia (P < 0.05). In consequence, the onset of blood lactate accumulation (OBLA) was shifted to a lower
O2 (
O2 1.77 l·min–1 in hypoxia vs 3.10 l·min–1 in normoxia). Lactate concentration increases relative to minute ventilation (
E) responses were significantly higher during hypoxia than in normoxia (P < 0.05). At OBLA,
E during hypoxia was 25% lower than in the normoxic test. This study would suggest that in hypoxia subjects are able to use an increased anaerobic metabolism to maintain exercise performance. 相似文献