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71.
L1, NCAM and N-cadherin are cell adhesion molecules (CAMs), present on neuronal growth cones, which promote cell-contact dependent axonal growth by activating a second messenger pathway in neurons that requires calcium influx through L- and N-type calcium channels. In the present study we show that two of these CAMs, (L1 and N-cadherin) can stimulate neurite regeneration from axotomised adult dorsal root ganglion (DRG) neurons cultured in vitro and that this response can be fully inhibited by agents that block or negate the effect of calcium influx into the neurons. However although the response required calcium influx into neurons, it was not associated with an increase in the steady state levels of calcium in neuronal growth cones. These results suggest that small localised changes, or increases in the rate of calcium cycling, in growth cones and/or filopodia, are more important for regulating axonal growth than changes in the steady-state level of calcium. 相似文献
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Hypodontia, congenitally missing teeth is more common in permanent than primary dentition. The present investigation reports the prevalence and pattern of hypodontia in the primary and permanent dentitions, excluding third molars in a sample of Saudi children. The sample consists of 1,300 children, aged 5 to 10 years of age. Clinical and radiographic examinations were performed. The prevalence of children with hypodontia was found to be 2.6 percent. The mandibular second premolar was the tooth most frequently absent and account for 45 percent of the total missing teeth. In primary dentition, the maxillary lateral incisor was the tooth most frequently absent (9%). A peg-shaped permanent maxillary lateral incisor was present in 0.7 percent of the sample. Congenitally missing teeth were almost equally distributed between maxillary (52%) and mandibular (48%) arches. 相似文献
75.
This study carried out in Hong Kong, identified 29 Chinese patients' perceptions of the importance of nursing care behaviours in an acute setting using a Chinese language translated version of the CARE-Q instrument. Patients ranked items concerned with 'giving the patients' treatments and medication on time' as the most important and 'sits down with the patient' as the least important. Comparisons are made with the results from other cultures and specific Chinese cultural interpretations are drawn to provide direction for nursing care of Chinese patients in Hong Kong and worldwide. 相似文献
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M Kunschak W Engl F Maritsch FS Rosen G Eder G Zerlauth HP Schwarz 《Canadian Metallurgical Quarterly》1998,38(6):540-549
BACKGROUND: No effective treatment exists in the United States for acute attacks of hereditary angioedema (HAE). STUDY DESIGN AND METHODS: To evaluate the efficacy and safety of C1 inhibitor concentrate in treating HAE, a large primary care and referral center hospital conducted a randomized, placebo-controlled, double-blind trial with intent-to-treat analysis. Of the 36 patients enrolled in the study, 23 received treatment, and 22 completed the trial. C1 inhibitor concentrate or albumin (placebo) infusions were administered in a blind fashion to HAE patients who came to the hospital for treatment no later than 5 hours after an attack began. RESULTS: Relief was almost twice as fast in persons receiving C1 inhibitor concentrate than in the controls: 7.62 hours (mean; SD 7.08) versus 15.35 hours (mean; SD 8.31), respectively. The difference for time-to-relief was highly significant (p = 0.007, Mann-Whitney U test). The median time-to-relief was 6.17 hours (interquartile range 0.33-15.35) in the treatment group and 15.35 hours (interquartile range 14.00-22.83) in the control group. Resolution of symptoms was one-third faster in the C1 inhibitor concentrate group than in the placebo group: 23.98 hours (mean; SD 14.81) and 34.58 hours (mean; SD 13.56), respectively (p = 0.09, Mann-Whitney U test). Recovery of functional C1 inhibitor was 119.65 percent (mean; SD 50.80), and half-life was 37.87 hours (mean; SD 19.75). Recovery of antigenic C1 inhibitor was 147.75 percent (mean; SD 97.68), and half-life was 24.01 hours (mean; SD 9.70). There were no viral infections or serious adverse effects from the drug after 70 attacks in the treatment group and 96 attacks in the control group. CONCLUSIONS: C1 inhibitor concentrate is a safe, effective treatment for acute attacks of HAE. 相似文献
78.
There have been numerous anecdotal reports of catastrophic falls in patients with fibrodysplasia ossificans progressiva. To determine the incidence of serious morbidity and mortality associated with falls in this patient population, the authors surveyed the 135 patient members of the International Fibrodysplasia Ossificans Progressiva Association and an age and gender matched control group. Eighty-one percent of the fibrodysplasia ossificans progressiva population suffered a fall resulting in injury compared with 44% of the controls. Sixty-seven percent of the falls initiated a painful flareup of fibrodysplasia ossificans progressiva leading to permanent loss of movement in almost all patients. Fifty-four percent of all falls suffered by the fibrodysplasia ossificans progressiva group led to permanent disability compared with 4% of all falls in the control group. Although trauma to the head was a common site of injury in both groups, the injury profile in the fibrodysplasia ossificans progressiva group included traumatic brain injuries, intracranial hemorrhage and death whereas the control group suffered mostly minor soft tissue lacerations. Deficiencies in coordinate gait and protective function likely accounted for the severity of injuries especially to the head in the fibrodysplasia ossificans progressiva population. Precautions are recommended that are intended to minimize the risk of injury without compromising a patient's functional level and independence. These recommendations include limitation of high risk activities, protective head gear, safety improvements in living environments, and augmentation of stabilizing and protective functions. 相似文献
79.
We randomised 50 patients with extracapsular fractures of the femoral neck to receive either a bupivacaine femoral nerve block or systemic analgesia alone. A femoral nerve block was found to be an easy and effective procedure which significantly reduced perioperative analgesic requirements and postoperative morbidity. 相似文献
80.
LA Baltina SA Ryzhova EV Vasil'eva GA Tolstikov GM Sakhautdinova FS Zarudi? 《Canadian Metallurgical Quarterly》1994,20(12):1365-1374
Triterpene glycopeptides, derivatives of glycyrrhizic acid, were synthesized with the use of tert-butyl esters of L-amino acids. The condensation of glycoside with esters was carried out with N-hydroxysuccinimide--N,N-dicyclohexylcarbodiimide or N-hydroxybenzotriazol--N,N'-dicyclohexylcarbodiimide in the presence of a base (triethylamine, N-methyl- or N-ethylmorpholine). The protection groups were removed with the use of trifluoroacetic acid. 相似文献