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91.
The present study was designed to investigate the possibility of activation of GABA(B) receptors during the motor inhibition caused by cannabimimetics. Adult male rats were injected with an acute dose of arachidonylethanolamide (AEA), Delta(9)- tetrahydrocannabinol (THC), beclofen or vehicle, after pretreatment with CGP 35348, a specific antagonist for GABA(B) receptors, or vehicle, and the behavioral response produced by these compounds tested in an open field. As expected, the administration of either AEA or THC produced a very pronounced motor inhibition, reflected by decreased ambulation and increased time spent in inactivity. The administration of baclofen also produced a marked motor deficit, with similar changes to those observed with both cannabimimetics. Pretreatment with the GABA(B) antagonist, CGP 35348, prevented the motor inhibition induced by baclofen and also attenuated the motor deficit caused by both cannabimimetics, suggesting a role for this receptor. In summary, a GABAergic influence, acting through GABA(B) receptors, seems to be involved in mediating motor effects of cannabimimetics, since the blockade of these receptors attenuates cannabimimetic-induced signs of motor inhibition.  相似文献   
92.
The effect of eight antimicrobial and three antineoplastic drugs on the uptake of fluconazole by human neutrophils and culture epithelial cells was evaluated. Fluconazole reached higher concentrations intracellularly than extracellularly (cellular to extracellular concentration ratio C/E 1.3) in the presence of therapeutical concentrations of the antimicrobial and antineoplastic agents evaluated.  相似文献   
93.
A Portuguese female, aged 47 years, who had emigrated to Spain, was admitted to the hospital in 1991 for pontine haematoma. The patient, four siblings and her father were affected by a peripheral neuropathy, indicating autosomal dominant inheritance. The patient presented in the 2nd decade with sensory and motor neuropathy beginning in the lower extremities. Alternating constipation and diarrhoea, and urinary incontinence became uncontrollable. She had to be colostomised, and, eventually, confined to a wheelchair from the age of 43. Neurological examination showed bilateral facial involvement, and severe signs of sensory and motor peripheral neuropathy, and later right hemiplegia. There were abnormalities of atrial rhythm and left bundle branch block. Computerised axial tomography and magnetic resonance images demonstrated left-sided pontine haemorrhage. Nerve conduction studies revealed severe diminution of motor conduction velocity and absence or reduction of amplitude of sensory and motor action potentials. Inanition and a respiratory infection led to her death. Clinical diagnosis was type I familial amyloid polyneuropathy (FAP). Postmortem examination demonstrated amyloid deposits in peripheral nerves, including spinal roots and cranial nerves, leptomeninges, thyroid, breasts, heart, adrenal glands, kidneys, intestines, pancreas, and meningeal and some pontine vascular structures. Advanced pontine haematoma was verified. Cerebral haemorrhage usually occurs with cerebrovascular amyloidosis, but exceptionally with FAP. A minority of patients presenting with CNS haemorrhage showed arteriovenous malformation or embolism [Da Silva Horta and Dias Coelho (1960) Arch de Vecchi Anal Patol Med Clin 31=163–172]. However, amyloid deposition in some small pontine vessels could have played a role in the pathogenesis of haemorrhage in the present case.  相似文献   
94.
95.
Summary The ultrastructure of melanosomes in mammalian epidermis has been studied using the freeze-fracture technique. The internal structure of the melanosome, as seen in cross-fractured granules, consists of a very fine particulate matter. There is no evidence of an internal membranous structure in melanosomes, indicating that the internal matrix which is characteristic of ultrathin sectioned material most likely represents cross-linked protein fibers.Fracture en-face of the melanosome limiting membrane reveals a random distribution of intramembrane particles on both the P- and E-faces of the membrane. There is a significantly higher density of IMPs on the P-face. The IMPs of the melanosome membrane may be involved in (a) selective passage of ions through the membrane, (b) membrane transducing events, and/or (c) anchoring sites for cytoplasmic fibrils and microfilaments.Research supported by USPHS Grant AM-20669 from the National Institute of Arthritis, Metabolism, and Digestive Diseases  相似文献   
96.
Contribution of a retrospective series of 16 patients with type II absorptive hypercalciuria over a total of 1.041 patients undergoing metabolic study due to relapsing renal lithiasis. Clinical history of lithiasis, biochemistry prior to treatment and instituted therapy were examined in all cases. Stones composition, radiologic appearance of lithiasis and evolution of biochemical parameters after medical treatment with a mixture of phosphates were also studied.  相似文献   
97.
The schwannoma is a tumor resulting from the Schwann cells of neural shwath, being its retroperitoneal localization quite unusual. This tumor is clinically unspecified and in most of the cases it originates symptoms coming from the compression of the close structures when its localization is retroperitoneal. Its diagnosis is quite often fortuitous being confirmed by anatomopathological study afterwards. The treatment is surgical radical exeresis with subsequent followup. We report a new case of this uncommon retroperitoneal pathology in a female patient showing a nonspecific clinic. Two years after the surgery she remains asymptomatic without any radiological evidence of recidive.  相似文献   
98.
Inverted papilloma is a rare tumour (2.2% of urothelial tumours) considered to be benign. The bladder is the most frequent site and growth tends to be endophytic towards the submucosa. Haematuria and obstruction symptoms appear to be the most typical clinical manifestations. Contribution of two cases of inverted bladder papilloma; one showing very unusual clinical development with relapsing acute urinary obstruction. Strict follow-up is recommended in spite of its benign behaviour as it may become associated to transitional cell carcinoma. Literature review on this tumoral entity in terms of etiology, clinical manifestations, diagnosis and treatment.  相似文献   
99.
100.
Microtia has been treated over the years with autogenous tissues, although the results continue to improve, it is technically a very demanding procedure, even in the hands of a well trained surgeon. Osseointegrated implant-supported ear prosthesis, is less demanding, more straightforward, and offers a better cosmetic result. Since 1996 we have treated 8 patients with microtia types III and IV, with titanium osseointegrated implant-supported ear prosthesis in the bone of the mastoid process. The surgical procedure consists in two stages. First stage: when the three titanium screws are drill in the mastoid process of the temporal bone, with a previous CT scan of the area, that is used to measured the bone thickness. Second stage is done 3 to 6 months later. Ear remnants are removed at the beginning of the procedure, three titanium couplings are then secured to the integrated fixtures, a plastic cap is attached to each of the abutments, until healing takes place; three to four weeks later the auricular prosthesis made out of silicone over a metallic structure, will we plug in the titanium screws. Cosmetic results and patients acceptability have been good in all 8 cases, with few postoperative complications. This procedure has become and option for the patients with ear malformations.  相似文献   
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