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81.
We investigated the role of donor bone marrow cell (DBMC) infusions in immunosuppression withdrawal in adult liver transplantation. Patients enrolled were at least 3 years post-transplantation, with stable graft function. Forty-five (study group: G1) received DBMC, and 59 (control group: G2) did not. Immunosuppression was reduced by one third upon enrollment, by another third the second year of the study and was completely withdrawn the third year. Patient and graft survival were similar between the two groups. Although rejection episodes were significantly less in G1 the first 2 years of the study (35% vs. 57%, p = 0.016), there was no significant difference overall (74% vs. 81%, p = 0.14). Until February 2004, 20 patients, 10 in each group, were immunosuppression free for 1-3 years. Approximately 20% of long-term survivors of liver transplantation can successfully discontinue their immunosuppression. DBMC infusions, do not increase this likelihood.  相似文献   
82.
The anterior cruciate ligament (ACL) serves as the primary restraint to anterior tibial translation. In addition to this biomechanical function, the ACL appears to have a function in neuromuscular control. This hypothesis was formulated after the discovery of mechanoreceptors within the ACL. The full somatosensory pathway from the ACL to the cerebrum has yet to be elucidated. In order to map this sensory pathway, we conducted a viral trans-synaptic tracing experiment using the neurotropic pseudorabies virus (PRV). The pseudorabies virus was injected into the ACL of rats and allowed to replicate and spread trans-synaptically for 6-7 days. The brain and spinal cord of each sacrificed rat was then removed and processed immunohistochemically to detect the presence of PRV. PRV-immunoreactive neurons were found to be localized in several different regions from the spinal cord to the cerebrum. Four nuclei in the reticular formation of the brain stem demonstrated strong positive labeling: the mesencephalic reticular nucleus, magnocellular reticular nucleus, paragigantocellular reticular nucleus, and gigantocellular reticular nucleus. This finding suggests that the nerve endings of the rat ACL project into the cerebrum and that the reticular formation may play an important role in the afferent pathway of those nerve endings.  相似文献   
83.
OBJECTIVE: Behavioral disturbances in dementia are extremely prominent and distressful, and often result in serious physical, social, and economic consequences. The authors compared the efficacy and tolerability of risperidone and haloperidol in the treatment of behavioral and psychological symptoms of dementia (BPSD) in institutionalized elderly Korean patients with Alzheimer disease, vascular dementia, or mixed dementia. METHODS: This was an 18-week double-blind, crossover study involving 120 patients who were randomly assigned to receive flexible doses (0.5-1.5 mg/day) of risperidone or haloperidol. BPSD were assessed using the Korean version of the Behavioral Pathology in Alzheimer's Disease Rating Scale (BEHAVE-AD-K), the Korean version of the Cohen-Mansfield Agitation Inventory (CMAI-K), and the Clinical Global Impression of Change scale (CGI-C). Safety and tolerability assessments included the Extrapyramidal Symptom Rating Scale and the incidence of adverse events. RESULTS: Both risperidone and haloperidol were efficacious in alleviating BPSD. However, when receiving risperidone, patients showed significantly greater improvement than when receiving haloperidol in the total and subscale scores of the BEHAVE-AD-K, the total and subscale scores of the CMAI-K, and the scores on the CGI-C scale. Also, risperidone had an additional benefit on aggressiveness and anxieties/phobias. The risk of antipsychotic-induced parkinsonism throughout this study was significantly lower with risperidone than with haloperidol. CONCLUSION: Risperidone had a favorable efficacy and tolerability profile compared with haloperidol in the treatment of BPSD in this patient population.  相似文献   
84.
Context Previous research on ethical issues encountered by medical professionals in training and practice have presented the thematic content of the cases they encounter rather than the activities in which clinicians engage and in which they most often encounter ethical issues. We conducted a direct observation study of paediatrics residents and their preceptors seeing patients in an out‐patient general paediatrics clinic. Our objectives were to describe the everyday ethics‐related issues paediatrics residents encounter as they interact with patients. Our ultimate goal is to use this knowledge to enhance current efforts to teach ethics to paediatrics residents. Methods The study team directly observed paediatrics residents discussing patients with their faculty preceptors (19 half‐day sessions, 76 hours) in an out‐patient general paediatrics clinic located in an urban academic medical centre. Each interaction between resident and preceptor about a single patient was considered a case for further analysis. Results A total of 247 cases were recorded. Forty‐one of the cases were coded as having ethics‐related content. A constant comparative method of qualitative data analysis revealed that residents were most likely to encounter ethical issues when engaged in the following activities: (i) maintaining a therapeutic alliance with the caregiver (e.g. the parent); (ii) prioritising patient or family needs; (iii) adjusting to the power embodied by the role of doctors, and (iv) distinguishing suboptimal care from abuse or neglect. In addition, our findings indicate that it is through their efforts to maintain the therapeutic alliance with the caregivers of their patients that residents engage in and integrate three processes: developing their medical knowledge; adhering to professional norms, and balancing the power inherent in the doctor’s role with their responsibility to serve the patient’s interests. Conclusions Medical faculty tasked with teaching ethics to paediatrics residents can utilise the results of this project to better target and enhance their ethics education efforts directed at residents in the out‐patient setting. Future research could further examine and test these findings in other clinical settings (e.g. adult general medicine).  相似文献   
85.
To evaluate the inhibitory activity of wogonin against lipopolysaccharide (LPS)-induced bone resorption, we investigated the effect of wogonin on osteoclastogenesis induced by LPS. Wogonin inhibited LPS-induced osteoclastogenesis in co-cultures of mouse calvaria-derived osteoblasts and bone marrow-derived pre-osteoclasts. Wogonin also suppressed osteoclastogenesis in LPS-injected mouse calvaria. In osteoblasts, the upregulation of receptor activator of nuclear factor-κB (RANKL) expression and the downregulation of osteoprotegerin (OPG) expression by LPS were inhibited by wogonin. Wogonin and NS-398, a COX-2 inhibitor, suppressed LPS-stimulated PGE2 production in osteoblasts. NS-398 inhibited the effect of LPS on RANKL and OPG expression in osteoblasts. These results suggest that wogonin acts as an inhibitor of LPS-induced osteoclastogenesis through downregulation of RANKL and upregulation of OPG expression via blockage of PGE2 production. Based on these results, wogonin has potential for use as a therapeutic agent in bacteria-induced bone resorption. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   
86.
87.
The stereoselective metabolism of lansoprazole enantiomers was evaluated by incubation of human liver microsomes and cDNA-expressed cytochrome p450 (p450) enzymes to understand and predict their stereoselective disposition in humans in vivo. The intrinsic clearances (Clint) of the formation of both hydroxy and sulfone metabolites from S-lansoprazole were 4.9- and 2.4-fold higher than those from the R-form, respectively. The sums of formation Clint of both metabolites were 13.5 and 57.3 microl/min/mg protein for R- and S-lansoprazole, respectively, suggesting that S-lansoprazole would be cleared more rapidly than the R-form. The p450 isoform selective inhibition study in liver microsomes, and the incubation study of cDNA-expressed enzymes, demonstrated that the stereoselective sulfoxidation is mediated by CYP3A4 and that the hydroxylation is mediated by CYP2C9 and CYP3A4 as well as by CYP2C19. Total Clint values of hydroxy and sulfone metabolite formation catalyzed by all these p450 enzymes were consistently higher for S-lansoprazole than for the R-form. The CYP3A4 produced the greatest difference of Clint between S- and R-enantiomers, mainly due to a difference of sulfoxidation metabolism (Clint 76.5 versus 10.8 microl/min/nmol of p450, respectively), whereas CYP2C19-catalyzed hydroxylation resulted in a minor difference of Clint between S- and R-enantiomers (179.6 versus 143.3 microl/min/nmol of p450, respectively). However, the affinity of CYP2C19 on hydroxylation was 5.7-fold higher for S-enantiomer than for the R-form (Km 2.3 versus 13.1 microM), suggesting that the role of CYP2C19 on stereoselective hydroxylation would be more prominent at concentrations around the usual therapeutic level. These findings suggest that both CYP2C19 and CYP3A4 are major enzymes contributing to the stereoselective disposition of lansoprazole, but stereoselective hydroxylation of lansoprazole enantiomers is mainly influenced by CYP2C19, especially at the usual therapeutic doses.  相似文献   
88.
The relationship between primary tumor proliferative activity and clinical and pathologic characteristics was analyzed in relation to menopausal status in 32 patients with malignant or benign breast disease. The thymidine labeling index (TLI) showed significantly higher median values in the cancer patients (3.48 per cent) than in the patients with benign diseases (1.02 per cent). TLI was not significantly affected by delayed incubation at room temperature for about 1 hour. In the breast cancer patients, TLI did not significantly correlate to tumor size, the presence of axillary lymph node metastasis or pathologic nuclear grading. The only significant difference was limited to the breast cancer patients without axillary lymph node metastasis in relation to menopausal status; the TLI in the premenopausal patients (5.10 per cent) was significantly higher (p<0.05) than that in the postmenopausal patients (2.28 per cent). These data thus suggest that among premenopausal patients without axillary lymph node metastasis, those with a high TLI could be potential candidates for adjuvant chemotherapy.  相似文献   
89.
The sperm penetration assay is an expensive, time-consuming test to assess male fertility in vitro. Although some investigators are enthusiastic in its application, others feel that it is not sensitive or specific enough to be used as part of the routine infertility evaluation. Indeed, this bioassay is not a faithful reproduction of in vivo conditions. However, if the SPA is abnormal, it is unlikely that sperm will fertilize a human ovum in vivo. Conversely, a normal SPA does not guarantee successful in vivo fertilization. No bioassay can be absolute in its predictive value, but false-negative results must be kept to a minimum for this bioassay to be of any clinical significance. Each laboratory performing the SPA should optimize the assay for sensitivity, reproducibility, and minimization of false-negative results and then establish normal and abnormal ranges of its own. If the limitations of the SPA are kept in mind, and if we employ it very selectively, it may still be useful.  相似文献   
90.
We report a case of congenital fistula from ectopic accessory parotid gland to the cheek demonstrated by CT sialography and CT fistulography. The right parotid gland was abnormally located lateral to masseter muscle. The fistula was arising from an ectopic accessory parotid gland with ectopic duct positioned anterior to masseter muscle. CT sialography and CT fistulography were very helpful in the diagnosis and surgical planning.  相似文献   
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