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51.
A 68-year-old man developed right homonymous hemianopic paracentral scotomas from acute infarction of the left extrastriate area. He was studied over the ensuing 12 months with visual fields, conventional MRI, functional MRI (fMRI), and diffusion tensor imaging (DTI). As the visual field defect became smaller, fMRI demonstrated progressively larger areas of cortical activation. DTI initially showed that the lesioned posterior optic radiations were completely interrupted. This interruption lessened in time and had disappeared by one year after onset. fMRI and DTI are innovative measures to follow functional and structural recovery in the central nervous system. This is the first reported application of these imaging techniques to acute cerebral visual field disorders.  相似文献   
52.
This study evaluated the effectiveness of early orthodontic treatment with the Twin-block appliance for the developing Class II Division 1 malocclusion. This multicenter trial was carried out in the United Kingdom. A total of 174 children, aged 8 to 10 years old, with Class II Division 1 malocclusion were randomly allocated to receive treatment with a Twin-block appliance or to an untreated, control group. Data were collected at the start of the study and 15 months later. Results showed that early treatment with Twin-block appliances resulted in reduction of overjet, correction of molar relationships, and reduction in severity of malocclusion. Most of this correction was due to dentoalveolar change, but some was due to favorable skeletal change. Early treatment with the Twin-block appliance is effective in reducing overjet and severity of malocclusion. The small change in the skeletal relationship might not be considered clinically significant.  相似文献   
53.
The purpose of this paper is to present the psychoanalytic individual psychodrama, as practiced in France within a psychiatric institution. After an overview of historical and theoretical issues, authors present a case report concerning the outcome of an adolescent suffering from schizophrenia, after ten years of treatment. The case analysis highlights the re-investment of mental functioning and the recover of the free association ability. Specially, authors describe the last year of the treatment and the pathways by which main psychical conflicts have been elaborated.  相似文献   
54.
Summary We report a case of a male patient suffering from a severe hemorrhagic radiation proctitis which gradually ceased with hyperbaric oxygen. We discuss the mechanisms of chronic radiation injury and the effect of the hyperbaric oxygen. This therapy is proposed as an alternative to surgical intervention for this abnormality.  相似文献   
55.
Toxoplasma encephalitis is the commonest cause of intracranial mass lesions in AIDS patients. Effective therapy includes pyrimethamine plus sulfadiazine, clindamycin with pyrimethamine, and co-trimoxazole. This study examines the efficacy of oral co-trimoxazole in 20 AIDS patients with toxoplasmosis and seeks to confirm the experience of Torre et al.  相似文献   
56.
Forty-four evaluable patients with intracranial meningiomas were assessed for the expression of the cell-cycle regulator cyclin D1 and of proteins involved in proliferation and apoptosis such as PCNA, MIB-1, p53 and bcl-2. Analyses were carried out by western blot and immunohistochemistry after immediate processing of fresh tumor specimens. By western blot, expression of cyclin D1 significantly correlated with p53 (p=0.02) and with proliferative activity, as assessed by PCNA expression (p=0.0009). By immunohistochemistry, a significant relationship between cyclin D1 and the proliferation marker MIB-1 was confirmed (p=0.05), whereas significance with bcl-2 expression was not found (p=0.01). Moreover, although the association with tumor grade appeared of borderline statistical significance (p=0.07), all the grade II/III meningiomas showed increased expression of cyclin D1 and high proliferative activity. In conclusion, data from this preliminary study seem to suggest a potential value of the combined expression of cyclin D1 and proliferation indicators in defining subgroups of meningiomas with a more aggressive biological behavior.  相似文献   
57.
Treatment of Ah-responsive C57BL/10ScSn mice with iron greatly sensitizes them to induction of hepatic porphyria and tumour formation by the polychlorinated biphenyl mixture Aroclor 1254. In the present studies, male C57BL/10ScSn mice received a single dose of iron-dextran (600 mg Fe/kg) and were fed a diet containing 0.01% Aroclor 1254 for 1, 3 and 5 weeks. By use of HPLC with electrochemical detection, 8-hydroxydeoxyguanosine (8-OHdG) was then measured in liver DNA as a marker for oxidative damage. Treatments with iron or Aroclor alone did not result in a significant increase in 8-OHdG except at 3 weeks following iron treatment. At 1 and 3 weeks 8-OHdG levels were induced approximately 3- and 5-fold above control groups respectively in iron- and Aroclor-treated animals. Although there was an apparent 5- to 10-fold increase in the level of 8-OHdG at 5 weeks, this was partially attributed to the in vitro effects of porphyrins, levels of which were massively elevated in liver at this time point. The iron/Aroclor-induced synergistic elevation of 8-OHdG at 1 and 3 weeks was concluded to be due to in vivo damage, thus suggesting the importance of DNA oxidation in the early events of carcinogenesis in this system.  相似文献   
58.
This study evaluated factors influencing fracture (n = 197) and osteotomy (n = 200) healing in children with moderate to severe OI. Pamidronate treatment was associated with delayed healing after osteotomy, but not after fracture. The data suggest that both pamidronate and mechanical factors influence bone healing in this cohort. INTRODUCTION: Intravenous pamidronate is widely used to treat children with moderate to severe osteogenesis imperfecta (OI). However, the effect of this treatment on bone healing is not well characterized. We therefore retrospectively analyzed the healing of lower limb fractures and osteotomies in children with moderate to severe OI, both before and after the start of pamidronate treatment. MATERIALS AND METHODS: Bone healing was evaluated on standard radiographs after 197 lower limb fractures (132 femur and 65 tibia) in 82 patients (age at fracture, 0.0-19.9 years) and 200 intramedullary rodding procedures in 79 patients (age at surgery, 1.2-19.8 years). Delayed healing was diagnosed when a fracture or osteotomy line was at least partially visible 12 months after the event. RESULTS: Delayed fracture healing was observed more frequently during than before pamidronate treatment. However, the effect of pamidronate was no longer significant when age differences were taken into account (odds ratio [OR], 1.76; 95% CI, 0.61-5.10). Better mobility status was a strong independent predictor of delayed healing after fractures that occurred during pamidronate treatment. After osteotomies, delayed healing was more frequent when pamidronate had been started before surgery (OR, 7.29; 95% CI, 2.62-20.3), and this effect persisted after adjustment for multiple confounders. During pamidronate treatment, older age (OR per year of age, 1.25; 95% CI, 1.06-1.47) and osteotomy of the tibia (OR, 3.51; 95% CI, 1.57-7.82) were independent predictors of delayed healing. CONCLUSIONS: This study suggests that pamidronate therapy is associated with delayed healing of osteotomy sites after intramedullary rodding procedures. Better mobility status, but not pamidronate treatment, seems to be predictive of delayed healing after fractures.  相似文献   
59.
Background: Tyrosine protein kinase proteins exert a prominent control on signaling pathways and may couple rapid events, such as action potential and neurotransmitter release, to long-lasting changes in synaptic strength and survival. Whether anesthetics modulate tyrosine kinase activity remains unknown. The aim of the current study was therefore to examine the effects of intravenous and volatile anesthetics on the phosphorylation of focal adhesion kinase (pp125FAK), a functionally important nonreceptor tyrosine kinase, in the rat hippocampus.

Methods: Phosphorylation of pp125FAK was examined in hippocampal slices by immunoblotting with both antiphosphotyrosine and specific anti-pp125FAK antibodies. Experiments were performed in the absence (control) or presence of various concentrations of pharmacologic or anesthetic agents or both.

Results: Clinically relevant concentrations of thiopental, propofol, etomidate, isoflurane, sevoflurane, and desflurane induced a concentration-related increase in tyrosine phosphorylation. In contrast, ketamine (up to 100 [mu]m) and the nonimmobilizer F6 (1,2-dichlorohexafluorocyclobutane, 25 [mu]m) did not significantly affect pp125FAK phosphorylation. The anesthetic-induced increase in pp125FAK phosphorylation was blocked by GF 109203X, RO 318220, and chelerythrin (100 [mu]m), three structurally distinct inhibitors of protein kinase C and U 73122 (50 [mu]m), an inhibitor of phospholipase C. The propofol- and isoflurane-induced increase in pp125FAK phosphorylation was reversible and showed nonadditivity of effects with phorbol 12-myristate 13-acetate (an activator of protein kinase C, 0.1 [mu]m). In contrast, ketamine (up to 100 [mu]m), MK801 (10 [mu]m, an N-methyl-d-aspartate receptor antagonist), bicuculline (10 [mu]m, a [gamma]-aminobutyric acid type A receptor antagonist), and dantrolene (30 [mu]m, an inhibitor of the ryanodine receptor) were ineffective in blocking anesthetic-induced activation of tyrosine phosphorylation.  相似文献   

60.
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