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111.
112.
BACKGROUND: This a prospective study of the incidence, etiology and epidemiological profile of human brucellosis in the regions of Pallars Jussà y Sobirà (Lleida) for the 1995-1998 period. METHODS: Fifty-five patients diagnosed as having brucellosis were studied. Information was recorded regarding the gender, age, town where residing, occupational hazard, contact with animals and intake of unsterilized dairy products, blood samples having been taken for blood cultures. RESULTS: A total of ten cases were reported in 1995, fourteen in 1996, fifteen in 1997 and sixteen in 1998, the average cumulative rates being 52 in Pallars Jussà and 129 in Pallars Sobirà. Four times more cases were reported among males (81.8%) than among females (18.2%) (RR: 4.4; CI95% 2.2-8.7). The largest number of cases occurred in March-April, and the fewest during the summer months. Seventy-one percent (71%) of these patients were working at an occupation involving this risk, the direct contagion mechanism being clearly prevalent (71%). The animal species most frequently considered to be the source of infection was that of sheep (65%), followed by cows (47%) and goats (25%). In Pallars Jussà, mainly sheep (RO: 0.3 CI95% 0.1-0.9) and in Pallars Sobirà, cows (RO: 6.6; CI95% 1.8-26.2). Twenty-seven strains of Brucella sp, all of the melitensis species, were isolated. CONCLUSIONS: The number of cases of brucellosis in the regions studied have risen in the 1995-1998 period. The results of study of this are indicative of the characteristic profile of an occupational disease. The etiological agent was Brucella melitensis, biovariety 1 clearly being the most prevalent. 相似文献
113.
Ghisleni G Porciúncula LO Cimarosti H Batista T Rocha J Salbego CG Souza DO 《Brain research》2003,986(1-2):196-199
Diphenyl diselenide (PhSe)2 is an organic selenium compound that has been little studied. In this study we investigated the effects of (PhSe)2 (0.1-3 microM) in a classical model of in vitro brain ischemia, which consists of exposing rat hippocampal slices to oxygen-glucose deprivation (OGD). Hippocampal slices were exposed for 60 min to OGD and the cellular viability (performed by MTT assay) as well as the immunocontent of nitric oxide synthase inducible (iNOS) were evaluated after 180 min of a recovery period. OGD decreased cellular viability by 50% and increased more than twice the immunocontent of iNOS of hippocampal slices. (PhSe)2 (1 and 3 microM) added during OGD and the recovery period abolished both effects. These results demonstrate for the first time the neuroprotective effects of (PhSe)2. Although the selenium analog--ebselen--has been widely used in ischemia models, our results suggest that other selenoorganic compounds could be investigated as pharmacological tools against brain disorders. 相似文献
114.
de Godoy CB 《Revista latino-americana de enfermagem》2002,10(4):596-603
The article had as its main goal to outline the history of the Nursing Curriculum of the State University of Londrina since its begining in 1972 until the present Curriculum, started in January 2000. The studying is based on a bibliographic research and the result has enabled us to outline all the changing process of the curriculum considering the professors disquiet and the work market demands. The studying, after substantiating all the curriculum changes, has contributed to better understand the pedagogical proposal that form the present integrated Curriculum of the Nursing Course of the State University of Londrina. 相似文献
115.
116.
The present study describes a monoclonal antibody-based enzyme immunoassay (ELISA) for the quantitation of lipoprotein(a), Lp(a), in human plasma. Two antibodies to Lp(a), 2F4E7 and 8G12G7, were produced and characterized as specific and high affinity antibodies against Lp(a). A reference control serum was utilized to prepare the standard curve in a Lp(a) concentration range from 0.015 to 0.5 ug/ml. A biotinylated monoclonal antibody against apoB-LDL was used as the second antibody. The comparison of the standardized ELISA using mAb 2F4E7 with an ELISA using a characterized mAb against Lp(a) (clone KO9) as capture antibody showed that the Lp(a) concentration of two standard sera was similar with both assays. Furthermore, when compared with an electroimmunoassay kit, similar Lp(a) concentrations for the standard were also obtained. 相似文献
117.
Godoy W Albano RM Moraes EG Pinho PR Nunes RA Saito EH Higa C Filho IM Kruel CD Schirmer CC Gurski R Lang MA Pinto LF 《Carcinogenesis》2002,23(4):611-616
Oesophageal cancer is one of the most common and lethal malignancies in the world. Despite many efforts, treatment is still ineffective for most cases; thus, the development of preventive strategies is crucial for decreasing the burden presented by this disease. Environmental factors, particularly nitrosamines, are thought to be involved in the genesis of oesophageal tumours, and knowledge about the expression of enzymes capable of activating pre-carcinogens in human oesophagus is very important for the development of preventive measures. We analysed the expression of CYP1A1, CYP1A2, CYP2A6/2A7, CYP2E1 and CYP3A4 mRNA in oesophageal mucosa of 50 patients by semi-quantitative RT-PCR. In five patients, who suffered from squamous cell carcinoma, we measured Nnitrosodimethylamine and N-nitrosodiethylamine metabolism in normal and tumorous tissue. CYP2A6/2A7 mRNA was expressed in 61% and CYP2E1 mRNA in 96% of the patients, but in the latter a lower degree of inter-individual variation was observed. These enzymes were expressed either in the distal or middle portions of the oesophagus of 90% of the patients. CYP1A1, CYP1A2 and CYP3A4 mRNA expression was not detected in any portion of the oesophagus. Oesophageal microsomes activated N-nitrosodimethylamine with a low degree of inter-individual variation and microsomes prepared from the tumour of a patient who strongly expressed CYP2A6/2A7 mRNA activated N-nitrosodiethylamine. We conclude that the human oesophagus expresses CYP2A6/2A7 and CYP2E1 and can activate nitrosamines. Notably, the expression of these enzymes is preferentially localized to the most common sites where tumours arise. 相似文献
118.
Cruz Portela LV Oses JP Silveira AL Schmidt AP Lara DR Oliveira Battastini AM Ramirez G Vinadé L Freitas Sarkis JJ Souza DO 《Brain research》2002,950(1-2):74-78
Adenine and guanine nucleotides have been shown to exert multiple roles in central and peripheral nervous systems, and the sequential breakdown of these nucleotides by enzymatic systems is an important step in the modulation of their extracellular effects. The aim of this study was to investigate whether nucleotide hydrolysis also occurs in the cerebrospinal fluid (CSF) of rats. CSF was able to hydrolyze all guanine and adenine nucleotides investigated (2.0 mM): GDPADP=ATP=GTPAMP=GMP. More detailed studies with the diphosphate nucleotides showed that the hydrolysis of ADP and GDP was linear with incubation time and protein concentration. The apparent KM (Henry–Michaelis–Menten constant) and V (maximal velocity) values for ADP and GDP were 164.3±54.7 μM and 12.2±3.8 nmol Pi/min per mg protein, and 841.0±90.2 μM and 22.8±8.0 nmol Pi/min per mg protein. The sum of ADP, GDP and UDP hydrolysis (2.0 mM) upon individual incubations with CSF was similar to the hydrolysis observed when all three nucleotides were incubated together. This pattern of hydrolysis strongly suggests the involvement of more than one enzyme activity. The higher maximum activity for GDP and UDP compared to ADP is compatible with presence of a soluble NTDPase5. 相似文献
119.
Eduardo S Ghisolfi Alice Schuch Ivo M Strimitzer Gustavo Luersen Fabíola F Martins Fernanda L P Ramos Jefferson Becker Diogo R Lara 《European neuropsychopharmacology》2006,16(3):204-210
The P50 suppression paradigm is an index of sensory gating assumed to reflect an inhibitory process. Adenosine is a neuromodulator with mostly inhibitory activity that is released by physiological stimuli and can be blocked by non-selective adenosine receptor antagonists such as theophylline and caffeine. A previous study showed that a single dose of theophylline decreased P50 suppression in healthy volunteers. Here we investigated the effect of caffeine (0, 100, 200 and 400 mg p.o.) on P50 sensory gating in 24 healthy volunteers (15 habitual caffeine high-users and 9 low-users). The 200 and 400 mg doses reduced P50 gating, whereas 100 mg produced a non-significant effect. The effect of caffeine was independent of gender and habitual caffeine intake. High caffeine users also showed baseline differences, with lower S(2) amplitudes compared to low-users. These results reinforce the participation of adenosine in the modulation of P50 sensory gating and suggest that caffeine ingestion should be controlled for in the P50 sensory gating paradigm. 相似文献
120.
Variables modulating stress and coping that discriminate drug consumers from low or nondrug consumers 总被引:4,自引:0,他引:4
López-Torrecillas F Godoy García JF Pérez García M Godoy Izquierdo D Sánchez-Barrera MB 《Addictive behaviors》2000,25(1):161-165
The present study assesses how certain stress and coping variables relate to drug use. A total of 124 subjects (85 men, 39 women) took part. They were divided into two groups: consumers and low or nonconsumers. Results indicate that consumers show significantly lower scores in self-control than low or nonconsumers. This research is of interest because it analyzes the relationship among assertiveness, self-control, self-efficacy, and drug use. We consider it worthwhile to take these variables into account when planning prevention programs. 相似文献