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The treatment of deep cartilage defects in load-bearing joints is a problem that still has no satisfactory solution. Full-thickness defects of the articular cartilage rarely heal spontaneously, usually leaving damage that can lead to early arthrosis. Techniques currently available for the treatment of chondral defects include abrasion, drilling, micro-fracturing, transplantation of tissue autografts and allografts, and cell transplantation. Osteochondral autograft transplantation is currently the only surgical cartilage repair technique known to lead to the formation of genuine hyaline articular cartilage and its retention at least in the medium term. The Draenert method, in which a water-cooled diamond bone-cutting system is used, is an effective procedure for resurfacing the joints affected by localised cartilaginous defects, even when there is also severe bone loss. Donor-side morbidity can be kept to a minimum by filling the defect caused by harvesting with a press-fit cylinder of cancellous bone covered with periosteum for protection.  相似文献   
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The literature suggests that pain in the elderly, especially among seniors with dementia, is under-assessed and under-treated.This qualitative study solicited the perspectives of seniors, front-line nursing staff, nursing-home administrators, and informal caregivers of seniors with dementia on the current status of pain assessment and management. The views of these participants complement the research findings reported in the literature. While some of their explanations and potential solutions concerning under-treatment of pain in seniors echo views that have been presented in the literature, the participants also pointed to factors and avenues that have been given less formal consideration (e.g., systemic barriers to effective assessment and treatment of pain).They also highlighted the need for pain-control strategies beyond medication. The implications of these findings are discussed.  相似文献   
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We explored the relationship between striatal dopamine-2 (D(2)) receptor occupancy and extra-pyramidal symptoms (EPS) in bipolar patients receiving olanzapine. Seventeen patients with a DSM-IV diagnosis of bipolar disorder were treated with 5-45 mg/day olanzapine for at least 14 days. After that period, D(2) receptor occupancy was determined using Iodobenzamide (IBZM) and SPECT. EPS were assessed by the Simpson-Angus Scale (SAS) and Barnes-Akathisia Scale (BAS). We found a dose-dependent increase in occupancy: 5 mg led to 28-50%, 10 mg to 40-68%, 15 mg to 69%, 20 mg to 57-66%, 30 mg to 66% and 45 mg to 80% D(2) receptor occupancy; and a significant correlation between plasma levels and occupancy (R(2)=.55, P=.001). Similar to schizophrenic patients, bipolar patients did not exhibit EPS at D(2) occupancy levels of 28 to 80%. Although we did not find an increased vulnerability for acute EPS in bipolar patients receiving olanzapine at clinical relevant doses, this needs to be replicated with larger sample sizes.  相似文献   
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The bed nucleus of the stria terminalis (BNST) and its adrenergic input are key components in stress-induced reinstatement and maintenance of drug use. Intra-BNST injections of either beta-adrenergic receptor (beta-AR) antagonists or alpha2-adrenergic receptor (alpha2-AR) agonists can inhibit footshock-induced reinstatement and maintenance of cocaine- and morphine-seeking. Using electrophysiological recording methods in an in vitro slice preparation from C57/Bl6j adult male mouse BNST, we have examined the effects of adrenergic receptor activation on excitatory synaptic transmission in the lateral dorsal supracommissural BNST (dBNST) and subcommissural BNST (vBNST). Alpha2-AR activation via UK-14,304 (10 microM) results in a decrease in excitatory transmission in both dBNST and vBNST, an effect predominantly dependent upon the alpha2A-AR subtype. Beta-AR activation via isoproterenol (1 microM) results in an increase in excitatory transmission in dBNST, but not in vBNST. Consistent with the work with receptor subtype specific agonists, application of the endogenous ligand norepinephrine (NE, 100 microM) elicits two distinct effects on glutamatergic transmission. In dBNST, NE elicits an increase in transmission (62% of dBNST NE experiments) or a decrease in transmission (38% of dBNST NE experiments). In vBNST, NE elicits a decrease in transmission in 100% of the experiments. In dBNST, the NE-induced increase in synaptic transmission is blocked by beta1/beta2- and beta2-, but not beta1-specific antagonists. In addition, this increase is also reduced by the alpha2-AR antagonist yohimbine and is absent in the alpha2A-AR knockout mouse. In vBNST, the NE-induced decrease in synaptic transmission is markedly reduced in the alpha2A-AR knockout mouse. Further experiments demonstrate that the actions of NE on glutamatergic transmission can be correlated with beta-AR function.  相似文献   
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