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91.
R. Christopher Pierce Amy J. Clemens Laura A. Shapiro George V. Rebec 《Psychopharmacology》1994,116(1):103-109
Acute administration of neuroleptic drugs alters the extracellular level of ascorbate in the neostriatum, and increasing evidence suggests a role for this vitamin in the behavioral, and possibly therapeutic, effects of these drugs. To shed further light on this issue, extracellular ascorbate was recorded in the neostriatum and nucleus accumbens of awake, behaving rats following chronic treatment with either classical (haloperidol) or atypical (clozapine) neuroleptics or ascorbate itself. Electrochemically modified, carbon-fiber microelectrodes were lowered in place the day after the last of 21 daily injections of either haloperidol (0.5 mg/kg, SC), clozapine (20 mg/kg, IP), sodium ascorbate (500 mg/kg, IP) or vehicle. Voltammetric measurements were obtained during quiet rest and following administration ofd-amphetamine (2.5 mg/kg). Repeated treatment with either haloperidol or ascorbate elevated basal extracellular ascorbate and potentiated the amphetamine-induced increase in ascorbate release in neostriatum but not nucleus accumbens. Both treatment groups also showed a significant increase in amphetamine-induced sniffing and repetitive head movements compared to vehicle-treated animals. In contrast, repeated clozapine had no effect on extracellular ascorbate in either neostriatum or nucleus accumbens, but increased the locomotor response to an amphetamine challenge. Thus, to the extent that increases in neostriatal ascorbate exert neuroleptic-like effects, such effects are likely to parallel haloperidol rather than clozapine. 相似文献
92.
Christopher J. Holmgren Esmonde F. Corbet L. P. Lim 《Community dentistry and oral epidemiology》1994,22(5):396-402
Abstract The aim of this study was to describe the periodontal conditions in 372 35–44-yr-old and 537 noninstitutionalized 65–74-yr-old Hong Kong Chinese who were examined clinically for loss of attachment, recession, probing depth, calculus, and bleeding after probing. Community Periodontal Index (CPI) data and treatment need indications were compiled from index teeth or their substitutes. The prevalence of loss of attachment varied considerably in both cohorts according to the definition of the threshold (≥6, ≥9, and ≥12 mm, respectively). The mean numbers of teeth with loss of attachment at the ≥6-mm threshold and at higher thresholds were small. In both age cohorts, about one-fifth of subjects had probing depths ≥6-mm, while al the ≥9-mm threshold only 2–3% were so affected. Although recession was an important component of loss of attachment in the younger cohort, in the older cohort the prevalence and extent of recession were greater than for probing depths at thresholds ≥4 mm. All subjects had one or more teeth with calculus, bleeding, or both, most teeth being so affected. Eighty-four of the 537 65–74-yr-old subjects were excluded either because of edentulousness or because extractions indicated for the remaining teeth would have rendered the subjects edentulous. The distribution of subjects according to their highest CPI score was remarkably similar for the two cohorts. No subjects in either age group were assessed as “healthy” (CPI code 0) or had “bleeding only” (code 1) as their highest score. While most subjects scored CPI code 2 or 3 us their highest score, only 17% of the younger and 15% of the older cohort scored Community Periodontal Index of Treatment Needs (CPITN) code 4. Differences in the mean number of sextants affected by CPI codes between the two cohorts were mainly due to a greater number of excluded sextants in the older cohort. CPI findings for 35–44-yr-olds differed little from those reported in 1984. 相似文献
93.
Evidence for in vivo incorporation of D-lactate into peptidoglycan precursors of vancomycin-resistant enterococci. 总被引:8,自引:0,他引:8 下载免费PDF全文
M Arthur C Molinas T D Bugg G D Wright C T Walsh P Courvalin 《Antimicrobial agents and chemotherapy》1992,36(4):867-869
The VanA ligase encoded by the vancomycin resistance plasmid pIP816 of Enterococcus faecium BM4147 condenses D-alanine with various D-2-hydroxy and D-2-amino acids in vitro. D-Lactate added to the culture medium restored the vancomycin resistance of a strain that does not produce the VanH dehydrogenase and therefore appears to be a substrate of VanA in vivo. 相似文献
94.
Developmentally-based AIDS/HIV Education 总被引:2,自引:0,他引:2
A growing number of health and education professionals argue that AIDS/HIV education curricula should be developmentally-based. They suggest the principles of developmental psychology be used to design curricula based on the sequentially ordered ways children of different ages understand AIDS. Relying on findings of research on development of children's conceptions of illness, a specific developmentally-based approach to educating school-age children about AIDS/HIV is presented in this paper. For each of three major age groups, the paper describes general characteristics for children's thought processes, ways in which children assimilate information about various aspects of AIDS, and implications for educating children about causes, prevention, and fear of AIDS. The focus of AIDS/HIV education can move from reducing fear in the younger group, to identifying and differentiating causes and noncauses of AIDS in the intermediate groups, to articulating strategies for AIDS prevention in the older group. 相似文献
95.
P C Walsh D M Quinlan R A Morton M S Steiner 《The Urologic clinics of North America》1990,17(3):679-684
The striated urethral sphincter is the predominant muscular structure divided posteriorly during the apical dissection in radical prostatectomy. The authors have long realized the value of this maneuver in obtaining excellent apical surgical margins and in identifying the correct plane on the anterior surface of the rectum. Recently, they also have recognized the importance of incorporating this musculature into the vesicourethral anastomosis to fix the bladder neck and thus re-establish anatomic continuity. Identification of the striated urethral sphincter ranks in importance with elucidation of the anatomy of the dorsal vein complex and the anatomic identification of the neurovascular bundle in improving the patient's quality of life postoperatively. 相似文献
96.
97.
Christopher Griffin MRACOG Michael John Peek PhD FRACOG DDU 《The Australian & New Zealand journal of obstetrics & gynaecology》1997,37(2):235-237
EDITORIAL COMMENT": The editorial committee found this case report irresistible as an example of triumph over misfortune and disability. Iatrogenic, accidental, prolonged and complete amnioreduction is unique in the editor's clinical experience and knowledge of the literature. Importantly the case also illustrates that conservative management of 'premature rupture of the membranes'can be successful. The favourable outcome may have been related to the abdominal rather than the usual cervical route of amnioreduction, and the restoration of normal liquor volume after the amnioreduction was discontinued. Moreover, in spontaneous rupture of the membranes the cause of the problem is likely to be persistent.
Summary: A successful outcome for an infant following complete iatrogenic amnioreduction at 20 weeks gestation is possible without any invasive medical treatment. 相似文献
Summary: A successful outcome for an infant following complete iatrogenic amnioreduction at 20 weeks gestation is possible without any invasive medical treatment. 相似文献
98.
99.
William V. Giannobile Rafaél A Hernandez Richard D. Finkelman Susan Ryarr Christopher P. Kiritsy Mark D'Andrea Samuel E. Lynch 《Journal of periodontal research》1996,31(5):301-312
Platelet-derived growth factor (PDGF) and insulin-like growth factor I (IGF-I) in combination have previously been shown to enhance periodontal regeneration. The objective of this study was to further characterize the biological effects of this combination of growth factors in non-human primates and compare the effects to those of each growth factor individually. Ligature-induced periodontitis was initiated in 10 cynomolgus monkeys. After periodontal lesions were established, surgery was performed, and either a methylcellulose gel vehicle or vehicle containing 10 μg each of either PDGF-BB, IGF-I or both PDGF-BB and IGF-I was applied to exposed root surfaces. Biopsies were taken 4 and 12 wk after treatment and the extent of periodontal regeneration was assessed by histomorphometry. At both 4 and 12 wk vehicle-treated lesions generally revealed minimal osseous defect fill (ODF) (8.5±2.1% and 14.5±5.7%, respectively) and new attachment (NA) (34.1±5.2% and 26.6±10.5%, respectively). IGF-I treatment did not significantly alter healing compared to vehicle in any parameter at both 4 and 12 wk. PDGFBB-treated sites exhibited significant (p<0.05) regeneration of NA (69.6±12.0%) at 12 wk; trends for PDGF-BB treatment effect were also observed in other parameters at 4 and 12 wk. although these increases were not statistically significant. Treatment with PDGF-BB/IGF-I resulted in 21.6±5.1 % and 42.5±8.3% ODF at 4 and 12 wk, respectively, and 64.1±7.7% and 74.6±7.4% NA at 4 and 12 wk, respectively (all significantly greater than vehicle, p<0.05). The results from this study demonstrated that: 1) IGF-1 alone at the dose tested did not significantly alter periodontal wound healing; 2) PDGF-BB alone significantly stimulated NA, with trends of effect on other parameters; and 3) the PDGF-BB/IGF-I combination resulted in significant increases in NA and ODF above vehicle at both 4 and 12 wk. 相似文献
100.
Andrew R. Hoellein MD Christopher A. Feddock MD Charles H. Griffith III MD MSPH John F. Wilson PhD Donald R. Barnett MD MSPH Pat F. Bass III MD MS T. Shawn Caudill MD MSPH 《Journal of general internal medicine》2004,19(5P2):562-565
Due to recent public debate and newly imposed resident work hour restrictions, we decided to investigate the relationship of resident call status to their ambulatory patients' satisfaction. Resident continuity clinic patients were asked to rate their level of satisfaction on a 10-point Likert-type scale. Using multiple regression approaches, these data were then assessed as a function of resident call status. We found that in 646 patient encounters, patient satisfaction scores were significantly less when the resident was postcall, 8.99 ± 1.8, than when not postcall, 9.31 ± 1.3. We herein discuss etiologies and implications of these findings for both patient care and medical education. 相似文献