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21.
Neuronal plasticity can manifest itself in alterations in the sensitivity of memory to the effects of drugs. After the production of a brain lesion, the memory processing of a passive-avoidance task in mice gradually becomes sensitive to the effect of morphine, i.e., an improvement in retention performance is seen after 6 weeks, but not after 1 or 2 weeks. The results presented demonstrate that, even if they lead to no discernible changes in behaviour, plastic processes can still be detected by means of behavioural tests.  相似文献   
22.
The expression of heat shock proteins (HSP) of the 65 kD family (groEL) has been observed by flow cytometry using murine monoclonal antibody (MoAb) anti-HSP 65 kD (ML30) on the surface of B (Daudi) or T (H9) lymphoma cells, on a monocyte cell line (U937) and also on a primary culture of a human pancreatic carcinoma (HPC). Moreover, the MoAb ML30 was coupled to Saporin 6, a ribosome-inactivating protein recovered from the seeds of Saponaria officinalis, to kill HSP-expressing cells with a specific immunotoxin. An indirect method using first MoAb ML30 and then anti-mouse IgG1 immunotoxin was also performed. With this method a human serum positive for HSP65-antibodies was tested using anti-human IgG1 or IgM immunotoxins. All cell lines were inhibited when preincubated with the specific immunotoxin directed to HSP65 (ML30 SO6), although H9 cells were susceptible to immunotoxin only after thermal stress. Daudi and HPC cells were inhibited both after long-term culture and when freshly explanted from SCID mice. Proliferation of the U937 monocytic cell line, that constitutively expresses high levels of HSP65 on the surface (as determined by flow cytometry), was completely inhibited (100% inhibition) by the ML30 SO6. However, not all tumour cells constitutively express high levels of surface HSP65, as determined by cytometric analysis. For this reason it was not always possible to obtain complete inhibition of cellular proliferation.  相似文献   
23.
A patient with end-stage renal failure inadvertently received high-dose hydrochlorothiazide as treatment for hypertension, resulting in CNS and cardiac toxicity. These toxic manifestations were successfully treated with hemodialysis. A hydrochlorothiazide dialysance of 62.5 mL/min was demonstrated. The possibility of hydrochlorothiazide toxicity should be considered in any patient with renal insufficiency who exhibits unexplained arrhythmias or symptoms related to the CNS.  相似文献   
24.
Amiodarone was injected endoneurially at increasing doses into the exposed tibial nerve of rats to study its electrophysiologic and pathologic effects on peripheral nerve fibers. Forty-five male Wistar rats were used, and each of the following concentrations was injected into 15 nerves: 25 micrograms/mL, 50 micrograms/mL, and 100 micrograms/mL. Microinjection of a 25 micrograms/mL concentration of amiodarone resulted in a subacute, incomplete conduction block evident at day 3 postinjection. This conduction block remained stable until day 10 and recovery was complete at day 35. Microinjection of a 50 micrograms/mL concentration of amiodarone produced a faster evolving conduction block, and significant axon degeneration (approximately 40% of fibers). Injection of a 100 micrograms/mL concentration resulted in severe acute motor axon degeneration followed by complete but delayed regeneration. Results of morphological studies closely correlated with electrophysiological findings. Amiodarone thus seems to have a direct toxic effect on axons at high concentrations in the peripheral nerve, and we suggest that different pathological changes described in human amiodarone neuropathy could be related to different concentrations of the drug in the nerve, perhaps due to variability of blood-nerve barrier efficacy.  相似文献   
25.
Atherosclerosis was induced in 20 Hanford miniature swine. Subsequently, one iliac artery lesion in each of 16 pigs was stented with either a self-expanding (8 pigs) or a balloon-expanded (8 pigs) stent. Immediately after stent placement, 4 animals in each group were taken off the atherogenic diet and continued on normal chow for the remainder of the study. Four months after stents were placed, atherosclerosis and the mural changes associated with the stent were more clearly evident in the arteries of the pigs continued on the atherogenic diet. These pigs also exhibited significantly more neointimal proliferation. In addition, the arteries containing the balloon-expanded stents showed more extensive and complex intimal changes when compared with arteries with self-expanding stents. Although both stent designs were equally effective in maintaining vascular patency, the balloon-expanded stent was more traumatic to the vessel wall which resulted in a significantly greater neointimal thickness.  相似文献   
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27.
This review focuses on estrogen role on human male physiology. Biological estrogen actions on male reproductive system are summarized with particular regard to the effects of congenital estrogen deprivation in men. The effects of estrogen on spermatogenesis, hormonal secretion and gonadotropin feedback and on sexual behavior are discussed. It is remarked that the role of estrogens in male reproduction is a very recent acquisition in reproductive endocrinology, but it promises new future fields of research to be investigated as well as the possible disclosure of new strategies in clinical practice.  相似文献   
28.
PURPOSE: To verify the emotional components expressed by the relatives of adult patients with a diagnosis of epilepsy, and whether they are related to adjustment to the illness and the course of the illness over time. METHODS: We studied a consecutive sample of 43 outpatients suffering from epilepsy and 43 key relatives using the Camberwell Family Interview (CFI), with the expressed emotion (EE) of the relatives being rated at baseline (T0). EE refers to a construct representing some key aspects of interpersonal relationships: the relatives were assigned to the high-EE group if they scored 3 or more on the emotional over involvement (EOI) scale, or showed hostility, or made 6 or more critical comments. The patients were clinically evaluated at baseline and for 1 year of appropriate treatment by an epileptologist who was blinded to the EE ratings. They also completed STAI XI, STAI X2 and Beck's Depression Inventory at baseline. RESULTS: Twenty-six relatives (60%) were rated as showing a high degree of EE. In the 12-month follow-up study, high EE and high EOI were found to be associated with a significantly higher seizure frequency than that recorded for the patients living in low-EE households (p<0.05). The patients from households assessed as reflecting a high degree of criticism showed poor drug compliance (p<0.01), whereas those with relatives assessed as having a high degree of warmth showed better clinical and pharmacological compliance (p<0.01). High family criticism scores also correlated with higher study entry levels of depression (p<0.05) and trait and state anxiety (p<0.05) among the patients. CONCLUSIONS: The study findings highlight the impact of particular components of the family emotional climate on the clinical course and psychological adjustment of patients with epilepsy.  相似文献   
29.
30.
The changes of intestinal permeability before and after a gluten load were studied. The study group comprised 27 patients with coeliac disease (mean age 12.3 years) and 19 healthy controls matched by sex and age. Intestinal permeability was studied by measuring the urinary excretion of two sugars, lactulose and L-rhamnose, before and six hours after the ingestion of five palatable biscuits made with 50 g of gluten powder. The patients with coeliac disease had been on a gluten free diet during the previous two years. After the gluten load lactulose and L-rhamnose urinary excretion changed significantly in patients, and a significant increase in the lactulose: L-rhamnose ratio was also observed. No significant changes were observed in the controls. In view of the modification of the three biopsies diagnostic protocol made by the European Society for Paediatric Gastroenterology and Nutrition, permeability tests associated with single gluten challenges may be an added contribution to the accuracy of the diagnosis in childhood.  相似文献   
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