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Hand preferences and whole (Galago senegalensis)   总被引:1,自引:0,他引:1  
The hand preferences in prey capture and whole-body turning biases after prey capture were assessed in 10 lesser bushbabies (Galago senegalensis) in 8 conditions designed to manipulate posture, visibility of prey and angle of reaching. Each subject received 60 trials in each test condition for a total of 480 trials. Seven subjects had a left-hand preference in food reaching, three right and none were ambipreferent. Eight subjects had a left whole-body turning bias, one right and one had no bias. No correlation was found between reach preference and turning bias. Bipedal posture facilitated the use of the dominant hand, whereas other manipulated conditions did not have a significant effect on hand use. A neuraxial arousal system is postulated as mediator of the bipedal effect on hand use.  相似文献   
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PURPOSE: Among patients at high risk for second molar (M2) periodontal defects after third molar (M3) removal, does active treatment at the time of extraction, when compared with no treatment, alter the risk of postextraction M2 periodontal defects? MATERIALS AND METHODS: We used a prospective cohort study design and a sample composed of subjects at high risk for developing M2 periodontal defects after M3 extraction, that is, age > or = 26 years, pre-existing periodontal defects (attachment level [AL] > or = 3 mm), and mesioangular or horizontal M3 impaction. The predictor variable was treatment status of the M3 extraction site. The M3 extraction sites were reconstructed with demineralized bone powder (DBP), bioresorbable guided tissue regeneration (GTR) therapy, or no treatment. The outcome variable was ALs measured at the M2 distobuccal line angle preoperatively and 26 weeks after extraction. Appropriate univariate, bivariate, and multivariate statistics were computed, and statistical significance was set at a value P < .05. RESULTS: The cohort was composed of 12 subjects contributing 18 high-risk M3s. Twenty-six weeks after M3 removal, the ALs for GTR-treated (3.0 +/- 1.2 mm), DBP-treated (1.4 +/- 0.5 mm), and control (3.8 +/- 0.9) M3 sites were statistically significantly different ( P = .002). Tukey post-hoc comparisons revealed a statistically significant difference between control and DBP ALs ( P = .001) and GTR-treated and DBP-treated ALs ( P = .037). There was no statistically significant difference in ALs between control and GTR-treated M3s ( P = .35). CONCLUSIONS: The results of this study suggest that subjects at high risk for developing M2 periodontal defects after M3 removal may benefit from the use of DBP placed at the time of M3 extraction to enhance periodontal healing.  相似文献   
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Many anaesthetists find themselves spending an increasing amount of time in the perioperative care of patients more than 65 years old. This article considers some aspects of anaesthesia for these patients which will help to ensure safe anaesthesia.  相似文献   
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Problems arising from controlled ovarian hyperstimulation for intrauterine insemination, such as premature luteinization and asynchronous ovarian follicular development, are identical to those encountered with controlled ovarian hyperstimulation for in vitro fertilization (IVF) and gamete intrafallopian transfer (GIFT). It has been suggested that the adjunctive use of GnRH agonists for controlled ovarian hyperstimulation improves the efficiency of GIFT and IVF cycles. We hypothesized that adjunctive use of leuprolide acetate, a GnRH agonist, would have a similarly beneficial effect on cycle quality and cycle fecundity in subfertile women treated with controlled ovarian hyperstimulation and intrauterine insemination. We randomly assigned the first cycle of controlled ovarian hyperstimulation and intrauterine insemination for each of 97 subfertile women to include either human menopausal gonadotropins (hMGs) alone or hMGs following midluteal pre-treatment with leuprolide. If a pregnancy did not occur in the first cycle, the woman was given the other treatment in the second cycle. Although the cycles that included leuprolide required a larger amount of hMGs and more days of stimulation per cycle, the mean estradiol concentrations and numbers of follicles were not different. Despite prevention of premature luteinization with leuprolide, the cycle fecundity was not different between groups (0.11 with adjunctive leuprolide treatment and 0.22 with hMGs alone). We conclude that in unselected subfertile patients, the adjunctive use of leuprolide for controlled ovarian hyperstimulation and intrauterine insemination does not improve cycle fecundity compared with treatment cycles that do not include adjunctive leuprolide therapy.  相似文献   
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OBJECTIVE: The object of this study was to apply evidence-based principles to answer the question, What is the risk of having periodontal defects on the distal aspect of the mandibular second molar (M2) following third molar (M3) removal? STUDY DESIGN: To identify relevant articles for review, we completed a computerized literature search of Medline. The inclusion criteria for articles included prospective cohort studies or randomized clinical trials with follow-up periods of 6 months or more, and preoperative and postoperative measurements of periodontal probing depths (PDs) or attachment levels (ALs). RESULTS: Eight articles met the inclusion criteria. Overall, the reported mean changes in ALs or PDs on the distal of M2 6 months after M3 removal were clinically insignificant, ie, less than 2 mm. Six months after M3 removal, 52% to 100% of subjects had no change or improvement in ALs or PDs. Given periodontal disease present preoperatively, the number needed to treat (NNT) ranged from 3 to 10. Given healthy periodontal status preoperatively, 48% had worsening of their periodontal measures after M3 removal and the number needed to harm (NNH) was 2. CONCLUSION: Commonly, the second molar periodontal probing depth or attachment levels either remain unchanged or improve after third molar removal. For subjects with healthy second molar periodontium preoperatively, the indication for third molar removal needs to be evaluated carefully as these subjects have an increased risk for worsening of probing depths or attachment levels after third molar removal.  相似文献   
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Special Pharmacokinetic Considerations in Children   总被引:4,自引:2,他引:2  
W. Edwin Dodson 《Epilepsia》1987,28(S1):S56-S69
Summary: Pediatric patients have greater degrees of pharmacokinetic variability and unpredictability than adults. This variability results from the effects of pharmacogenetics, age and growth, prior and current comedication, and disease. Newborns with seizures have the least predictable dosage requirements, and their needs change as drug-eliminating mechanisms mature in the neonatal period. Infants have the highest relative capacities to eliminate antiepileptics of any age group and require the largest relative doses. In addition to age-related trends, children demonstrate the same drug-specific, pharmacokinetic phenomena that adults do, including nonlinear phenytoin elimination, nonlinear valproate binding, and autoinduction of carbamazepine. Intercurrent illness and drug interactions further modify the age-related pharmacokinetic patterns in children and make dosage requirements even more unpredictable. Recent studies have shown that febrile illness can affect drug elimination, sometimes decreasing drug levels by 50% or more. Intermittent treatment with benzodiazepines administered either orally or rectally can be an important adjunct and help minimize this type of problem for children with marginally controlled epilepsy. Intermittent benzodiazepines are also helpful for children who have febrile seizures and who need only occasional antiepileptic protection.  相似文献   
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