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991.
Dentsply Cavitron Diamond Inserts provide improved efficacy in removing calculus from furcations. A total of 60 extracted human mandibular molar teeth had artificial calculus applied to the furcations, then were randomly treated with either sharp universal Gracey curettes (HAND), a plain ultrasonic TFI-10 tip in a cavitron instrument (CAV), or one of 2 diamond-coated cavitron instruments (TFI-10 fine-grit (FIN) and TFI-10 medium-grit (MED)) When the time needed to completely clean the furcations was evaluated, MED was the fastest, followed by FIN, CAV, and HAND, respectively. All of the powered instruments were faster than hand curettes with regard to effective in vitro calculus removal in furcations. The use of these types of instruments would reduce the time required to perform periodontal surgery and might improve regenerative therapy.  相似文献   
992.
The effectiveness and transportability of multisystemic therapy (MST) were examined in a study that included 118 juvenile offenders meeting DSM-III-R criteria for substance abuse or dependence and their families. Participants were randomly assigned to receive MST versus usual community services. Outcome measures assessed drug use, criminal activity, and days in out-of-home placement at posttreatment (T2) and at a 6-month posttreatment follow-up (T3); also treatment adherence was examined from multiple perspectives (i.e., caregiver, youth, and therapist). MST reduced alcohol, marijuana, and other drug use at T2 and total days in out-of-home placement by 50% at T3. Reductions in criminal activity, however, were not as large as have been obtained previously for MST. Examination of treatment adherence measures suggests that the modest results of MST were due, at least in part, to difficulty in transporting this complex treatment model from the direct control of its developers. Increased emphasis on quality assurance mechanisms to enhance treatment fidelity may help overcome barriers to transportability.  相似文献   
993.
BACKGROUND: Insomnia is a very common symptom, particularly in the elderly. Thus, all hypnotic medications should be carefully evaluated in the elderly population. Zaleplon, a new nonbenzodiazepine hypnotic with a short elimination half-life (approximately 1 hour), was evaluated in the current study. METHOD: This multicenter, randomized, placebo-controlled outpatient study evaluated the efficacy and safety of zaleplon, 5 and 10 mg, in elderly patients with insomnia (as defined by DSM-IV); zolpidem, 5 mg, was the active comparator. Sleep was assessed in 549 elderly patients (>/= 65 years old) by using morning questionnaires completed after each of 7 baseline nights during which placebo was given, 14 nights of double-blind treatment, and 7 nights of placebo after discontinuation of active treatment. RESULTS: Zaleplon, 10 mg, and zolpidem, 5 mg, significantly reduced sleep latency during both weeks of the study. Zaleplon, 5 mg, reduced sleep latency only during week 2. Sleep duration was increased with zolpidem, 5 mg, during weeks 1 and 2 and with zaleplon, 10 mg, during week 1. No clinically significant rebound insomnia was observed after discontinuation of treatment with zaleplon, whereas evidence of rebound effects was seen with zolpidem. There was no significant difference between either zaleplon dose and placebo in the frequency of any central nervous system adverse events. CONCLUSION: Zaleplon is effective in reducing latency to sleep without evidence of undesired effects in elderly patients with insomnia.  相似文献   
994.
Involvement of the central nervous system in epithelial ovarian carcinoma is rare. A 46-year-old woman with ovarian carcinoma relapsing with brain metastasis is described. She received radiotherapy for the metastasis and survived for 18 months.  相似文献   
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 The present study investigated the pathogenesis and the time course of kidney injury in experimental IgA nephropathy. In order to determine an appropriate period in the course of experimental IgA nephropathy to study renal injury and repair, we examined proteinuria and IgA deposition in the renal mesangium after 4, 8, and 16 weeks of mucosal challenge by bovine gamma globulins (BGG) provided in the drinking water. The hallmark of IgA deposition in the mesangium was present after 4 weeks and 8 weeks of BGG inoculation, but by 16 weeks, the mesangial IgA deposition had resolved. In addition, we confirmed our previous report on the beneficial effects of α-tocopherol in reducing proteinuria in IgA nephropathy at 8 weeks, and extended this observation to investigate the effects of dietary supplementation of α-tocopherol at both 4 weeks and 16 weeks. Proteinuria resolved spontaneously at 16 weeks. There is oxidative stress, as suggested by the elevation in plasma and renal malondialdehyde content, and increased fibrogenic cytokine message, as suggested by elevated transforming growth factor β1 mRNA. These increases were clearly blunted by α-tocopherol at both 4 weeks and 8 weeks. Treatment with α-tocopherol was associated with a significant reduction in the severity of proteinuria. Thus, our data suggest that the period between 4 and 8 weeks of BGG vaccination could be relevant in designing an appropriate model to study the molecular biology of the pathogenesis of renal injury and the effects of treatment. The 16-week model may be useful in exploring gene expression involved with spontaneous resolution. Received: 17 February 1998 / Revised: 2 June 1998 / Accepted: 3 June 1998  相似文献   
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999.
Apoptosis of neurones, macrophages, and microglia occurs in the brains of paediatric patients with human immunodeficiency virus (HIV) type 1 encephalitis, which is often associated with pre-mortem neurological disease (progressive encephalopathy). We have previously reported that TUNEL-positive neurones in brain tissue from paediatric patients with HIV type 1 encephalitis and progressive encephalopathy are strikingly devoid of the pro-apoptotic gene product Bax, in marked contrast to brain-resident macrophages and microglia. Using immunocytochemical methods, the present study demonstrate that neurones in patients with HIV type 1 encephalitis and progressive encephalopathy, as well as macrophages and microglia, but not astrocytes, overexpress caspase-3, a pro-apoptotic enzyme that is proteolytically activated downstream of Bax-Bcl-2 dysregulation. Co-localization of neuronal cytoplasmic caspase-3 and nuclear TUNEL staining, a marker for fragmented DNA, was also infrequently observed in brain tissue from patients with HIV type 1 encephalitis and progressive encephalopathy. These findings suggest that vulnerable neurones in brain tissue from patients with HIV virus type 1 encephalitis and progressive encephalopathy undergo apoptosis by a mechanism that involves upregulation of caspase-3 in a pathway that is independent of Bax-Bcl-2 dysregulation. Furthermore, caspase-3 upregulation in apoptotic neurones likely occurs prior to DNA fragmentation.  相似文献   
1000.
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