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41.
Radiological findings in 12 cases of "Mediterranean" lymphoma are analyzed, 4 of which are associated with gammapathy. These findings have not permitted differentiation of this type of lymphoma from those classically described, although there are two signs that strongly suggest this diagnosis: extension of the lesions along wide areas of the small intestine, almost always including the duodenum, and spiculation of the mucosal fold edges, representing massive plasmocyte infiltration of the lamina propria. The principal clinical, immunological, and pathological aspects are described, as well as the radiological differential diagnosis.  相似文献   
42.
In order to simplify breeding of triatominae in the laboratory, for performing xenodiagnosis and other biologic studies, we tried to feed the insects "in vitro" with citrated or defibrinated blood from commercially abated chicken. Two types of efficacy observations were carried out with Triatoma infestans: a) analysis of the chaining of successive nymphal stages, viability of satisfactory matching, fertile oviposition and adequate reproduction; b) assessment of viability and infectivity of Trypanosoma cruzi in the insects. As a conclusion, it became evident that, despite operational easiness, the objectives were not achieved, since the classical procedure used as the control, was always superior.  相似文献   
43.
A number of neurotoxins from venoms of invertebrates and plants are ligands for voltage-gated Na+ channels and are useful tools for studying Na+ channel function and structure. Using whole-cell recordings from vagal afferent nodose neurons, we studied neurotoxins that target Na+ channels. We asked whether Ts3 (an α-scorpion toxin) and/or veratridine (a lipid-soluble toxin), could modify the TTX-resistant Na+ current generated by vagal afferent nodose neurons. Nodose TTX-resistant current was not affected by Ts3, whereas Ts3 slowed inactivation of the current generated by TTX-sensitive current component. We found that veratridine inhibited the TTX-resistant Na+ currents on rat nodose neurons. Interestingly, veratridine-modified Na+ channels developed a persistent current that accounted for the large tail current observed. We propose that veratridine modifies TTX-resistant Na+ channels through a mechanism distinct from its actions on other voltage-gated Na+ channels.  相似文献   
44.
PURPOSE: To assess whether tumour proliferation as measured by Ki67 immunostaining has any predictive value for local control in bladder cancer patients treated by radiotherapy. PATIENTS AND METHODS: Fifty-five patients suffering from infiltrating bladder carcinoma recommended for radical radiotherapy (66 Gy/6-7 weeks) were included in this study. Paraffin-embedded pre-treatment tumour sections were stained with the Ki67 antibody. The percentage of Ki67-positive nuclei was correlated with established prognostic factors, local control and survival. RESULTS: The Ki67 index was not related to local control in our patients when the median was selected as the cut-off value. Patients with tumours with a very low (<27%) Ki67 index had better local control at 5 years (69%) than patients with tumours with greater (>27%) Ki67 expression indices (31.5%) (P<0.05; log-rank test). CONCLUSIONS: Ki67 immunostaining was a feasible method to estimate tumour proliferation. Patients with very low proliferating tumours seemed to achieve better local control after fractionated radiotherapy compared to other patients. Further studies are needed with a greater number of patients to accurately define the role of Ki67 expression in predicting tumour repopulation during fractionated radiotherapy.  相似文献   
45.
OBJECTIVES: The fibreoptic device is a type of intracranial pressure monitor which seems to offer certain advantages over conventional monitoring systems. This study was undertaken to analyse the accuracy, drift characteristics, and complications of the Camino fibreoptic device. METHODS: One hundred and eight Camino intracranial pressure (ICP) devices, in their three modalities, were implanted during 1997. The most frequent indication for monitoring was severe head injury due to road traffic accidents. RESULTS: Sixty eight probe tips were cultured; 13.2% of the cases had a positive culture without clinical signs of infection, and 2.9% had a positive culture with clinical signs of ventriculitis. The most common isolated pathogen was Staphylococcus epidermidis. All patients were under cephalosporin prophylaxis during monitoring. Haemorrhage rate in patients without coagulation disorders was 2.1% and 15.3% in patients with coagulation abnormalities. Drift characteristics were studied in 56 cases; there was no drifting from the values expected according to the manufacturer's specifications in 34 probes. There was no relation between direction of the drift and duration of placement, nor between drift and time. CONCLUSIONS: Although the complication and drift rates were similar to those reported elsewhere, there was no correlation between the direction of the drift and long term monitoring despite the fact that some published papers refer to overestimation of values with time with this type of device.  相似文献   
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Bites of brown spiders (Loxosceles spp.) are responsible for dermonecrotic lesions and potentially systemic envenoming that can lead to death. The only effective therapy is the use of the antivenom, usually produced in horses. However, little is known about the consequences of the systematic use of the Loxosceles venom and adjuvants and of the bleedings on antivenom-producing horses. Thus, the aim of this study was to evaluate the clinical changes in horses in their first immunization protocol for Loxosceles antivenom production. Eleven healthy horses, never immunized, were evaluated in three different periods: T0 (before immunization); T1 (after their first venom immunization); and T2 (after their first bleeding). Horses were clinically evaluated, sampled for blood, and underwent electrocardiographic (ECG) recordings. Several suppurated subcutaneous abscesses occurred due to the use of Freund’s adjuvants and thrombophlebitis due to systematic venipunctures for the bleeding procedures. ECG showed arrhythmias in few horses in T2, such as an increase in T and R waves. In summary, the immunization protocol impacted on horses’ health, especially after bleeding for antivenom procurement.  相似文献   
49.

Ethnopharmacological relevance

The study was aimed at evaluating medicinal and therapeutic potentials of two Lycopodiaceae species, Lycopodium clavatum (L.) and Lycopodium thyoides (Humb. & Bonpl. ex Willd), both used in South American folk medicine for central nervous system conditions. Alkaloid extracts were evaluated for chemical characterization, acetylcholinesterase and antioxidant activities.

Materials and methods

The alkaloid extracts obtained by alkaline extraction were determined for each species by GC/MS examination. The evaluation of the anticholinesterase and the antioxidant activities of the extracts were tested by determining in vitro and ex vivo models. Effects on acetylcholinesterase (AChE) were tested in vitro using rat brain homogenates and ex vivo after a single administration (25, 10 and 1 mg/kg i.p.) of the alkaloid extracts in mice. The in vitro antioxidant effects were tested for the 2-deoxyribose degradation, nitric oxide (NO) interaction, 2,2-diphenyl-1-picryl hydrazyl (DPPH) radical scavenging activity and total reactive antioxidant potential (TRAP). After an acute administration (25 and 10 mg/kg i.p.) of the extracts in middle-aged (12 months) mice, the antioxidant effects were estimated through the thiobarbituric acid reactive substances test (TBARS), and the antioxidant enzymes activities for catalase (CAT) and superoxide dismutase (SOD) were measured.

Results

AChE activity was inhibited in vitro by the alkaloid-enriched extracts of both Lycopodium species in a dose and time-dependent manner in rat cortex, striatum and hippocampus. A significant inhibition was also observed in areas of the brain after acute administration of extracts, as well as decreased lipid peroxidation and increased CAT activity in the cortex, hippocampus and cerebellum. A moderate antioxidant activity was observed in vitro for the extracts. Chemically, the main alkaloids found for the two species were lycopodine and acetyldihidrolycopodine.

Conclusion

This study showed that the biological properties of the folk medicinal plants Lycopodium clavatum and Lycopodium thyoides include AChE inhibitory activity and antioxidant effects, two possible mechanisms of action in Alzheimer's related processes.  相似文献   
50.
Purpose The purpose of the study was to evaluate the effect on visual function of orally administered CDP-choline in addition to patching for the treatment of amblyopia in children. Methods This was an open label parallel group study comparing patching plus oral CDP-choline with patching alone. Sixty-one participants (aged between 5 and 10 years) suffering from anisometropic or strabismic amblyopia were divided at random into two groups: Group A, 800 or 1,200 mg (according to the body weight) of orally administered CDP-choline and 2-h patching a day; Group B, 2-h patching a day. Both groups were treated for 30 consecutive days. A follow-up visit was set 60 days after the treatment was discontinued. The main outcome measure was the change in visual acuity of amblyopic eyes as measured by Snellen’s E charts. The secondary outcome measures were changes in the visual acuity of amblyopic eye as measured by isolated letters (Snellen’s E) and changes in the contrast sensitivity of amblyopic eyes. Results The addition of CDP-choline to patching therapy was not found to be more effective than patching alone after 30-day treatment. The present results showed that adding CDP-choline to patching stabilised the effects obtained during the treatment period. In fact, whereas the participants treated only with patching showed a decrease in visual acuity at 90 days, these receiving CDP-choline and patching combined appeared to maintain the results obtained (two-way ANOVA: P = 0.0042). Similar results were obtained when measuring visual acuity by isolated Snellen’s E letters. Conclusions In amblyopic patients, CDP-choline combined with patching contributes to obtaining more stable effects than patching alone. Fabio De Gregorio works as an advisor for Tubilux Pharma S.p.A. The authors have full control of all primary data and they agree to allow Graefe’s Archives for Clinical and Experimental Ophthalmology to review their data if requested.  相似文献   
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