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41.
Daniel T Richardson Thomas B Dodson 《Oral surgery, oral medicine, oral pathology, oral radiology, and endodontics》2005,100(2):133-137
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
42.
T H Richardson J B Schenkman R Turcan P S Goldfarb G G Gibson 《Xenobiotica; the fate of foreign compounds in biological systems》1992,22(6):621-631
1. A polyclonal, monospecific antibody to a constitutive, diabetes-inducible and insulin-reversible cytochrome P-450 isozyme (RLM6) was used to screen a male rat liver cDNA library in lambda gt 11. Six clones harbouring the RLM6 cDNA insert were isolated initially from the expression library and three of these were further plaque-purified and sub-cloned. A 1.1 Kb cDNA insert, representing approximately 65% of the expected full length cDNA was characterized by restriction endonuclease mapping and sequenced by the dideoxy chain-termination method. Comparison of the nucleotide sequence of RLM6 cDNA to that of ethanol-inducible P4502E1 rat cDNA showed the two cDNAs to be identical, the RLM6 cDNA corresponding to nucleotides 310-1402 of the P4502E1 sequence. 2. RLM6 cDNA probe was used in Northern blot and RNA dot blot hybridization analysis to demonstrate that both streptozotocin-induced diabetes and fasting significantly elevated the steady-state level of RLM6 mRNA in male rat liver. Increased RLM6 mRNA level in the diabetic rat resulted in increased RLM6 apoprotein synthesis when polysomal RNA was used in a cell-free, protein-synthesizing system, indicating that the elevated RLM6 level observed in diabetic rats was correlated directly with the increased RLM6 mRNA concentration. 3. Daily insulin treatment of diabetic rats reversed the diabetes-dependent increase in RLM6 mRNA in a time-dependent manner, returning to control values after approximately 2 weeks of continuous insulin treatment. This insulin-dependent decrease of the RLM6 mRNA level was paralleled by a similar time-dependent decrease in serum acetone concentration. 4. Treatment of the male diabetic rat with testosterone also resulted in a decrease in both RLM6 mRNA and in vitro translated apoprotein. 5. Modulation of RLM6 mRNA level in the diabetic rat by insulin and testosterone, and the nucleotide sequence similarity with that of P4502E1 confirms that diabetes-inducible P450RLM6 and ethanol-inducible P4502E1 are coded for by the same gene. 相似文献
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Patients with intracerebral haematomas (ICH) secondary to aneurysmal bleeds usually have a poor prognosis or die if treated conservatively. Younger patients with rupture of a middle cerebral artery (MCA) aneurysm and temporal haematomas have the potential to return to useful life. They should be assessed separately from other subarachnoid haemorrhage (SAH) patients and considered for emergency surgery. Seven such cases are presented, five made an acceptable recovery. The experience of other units as represented in the literature is considered. 相似文献
45.
46.
T C Richardson J A Humphreys K M Townsend 《British journal of experimental pathology》1987,68(3):359-368
An experimental system has been devised for the study of tissue reaction to the subcutaneous implantation of double velour Dacron into the mouse. Animals were given Dacron implants for 3 months, 2 months, 1 month, 3 weeks, 2 weeks and 1 week and the infiltration of the material was assessed using light-microscopy, autoradiography, electron-microscopy and angiography. It was found that the implants became extensively infiltrated with host cells, the response being at a peak in the second and third weeks post-implantation. Macrophages were seen from an early stage, fibroblasts were numerous, and new capillaries penetrated the material. The observations, especially the angiogenic response, are discussed with reference to published information on the actions of the cell types that were seen, in particular the macrophage. 相似文献
47.
A double blind, randomised, parallel group study to investigate
the dose equivalence of Dysport® and Botox®
in the treatment of cervical dystonia 下载免费PDF全文
T Odergren H Hjaltason S Kaakkola G Solders J Hanko C Fehling R Marttila H Lundh S Gedin I Westergren A Richardson C Dott H Cohen 《Journal of neurology, neurosurgery, and psychiatry》1998,64(1):6-12
OBJECTIVE—This study was designed toestablish whether a ratio of three units of Dysport® isequivalent to one unit of Botox® for the treatment ofcervical dystonia.
METHODS—Patients with predominantly rotationalcervical dystonia, and a minimum of four previous Botox treatments,were randomised to receive either the clinically indicated dose ofBotox or three times that dose in Dysport units. Study botulinum toxinwas administered in a double blind fashion, to one or more clinicallyindicated muscles, at one or more sites per muscle. Patients returnedfor assessment two, four, eight, and 12 weeks after treatment.
RESULTS—A total of 73 patients (Dysport, 38;Botox, 35) were entered. The Dysport group received a mean (SD) dose of477 (131) (range 240-720) Dysport units, and the Botox group receiveda mean (SD) dose of 152 (45) (range 70-240) Botox units. The mean(SEM) post-treatment Tsui scores for the Dysport group (4.8 (0.3)) andthe Botox group (5.0 (0.3)) were not statistically different (p=0.66).The study had 91% power to detect a clinically significant differenceof two points. Both groups showed substantial improvement in Tsui scoreby week 2 (mean (SD); Dysport, 46 (28)%; Botox, 37 (28)%), with apeak effect at week 4 (mean (SD); Dysport, 49 (29)%; Botox, 44 (28)%). A similar response profile was seen for other assessments ofefficacy. The duration of effect, assessed by time to retreatment, wasalso similar (mean (SD); Dysport, 83.9 (13.6) days; Botox, 80.7 (14.4)days; p=0.85). During the study 22 of 38 (58%) Dysport patientsreported 39 adverse events, and 24 of 35 (69%) Botox patients reported56 adverse events (p=0.35). A global assessment of efficacy and safetyconsidered that 29 of 38 (76%) Dysport patients and 23 of 35 (66%)Botox patients were treatment successes (p=0.32).
CONCLUSION—Patients with predominantly rotationalcervical dystonia treated with the clinically indicated dose of Botoxor three times that dose in Dysport units show similar improvements anddo not have significantly different safety profiles.
相似文献
METHODS—Patients with predominantly rotationalcervical dystonia, and a minimum of four previous Botox treatments,were randomised to receive either the clinically indicated dose ofBotox or three times that dose in Dysport units. Study botulinum toxinwas administered in a double blind fashion, to one or more clinicallyindicated muscles, at one or more sites per muscle. Patients returnedfor assessment two, four, eight, and 12 weeks after treatment.
RESULTS—A total of 73 patients (Dysport, 38;Botox, 35) were entered. The Dysport group received a mean (SD) dose of477 (131) (range 240-720) Dysport units, and the Botox group receiveda mean (SD) dose of 152 (45) (range 70-240) Botox units. The mean(SEM) post-treatment Tsui scores for the Dysport group (4.8 (0.3)) andthe Botox group (5.0 (0.3)) were not statistically different (p=0.66).The study had 91% power to detect a clinically significant differenceof two points. Both groups showed substantial improvement in Tsui scoreby week 2 (mean (SD); Dysport, 46 (28)%; Botox, 37 (28)%), with apeak effect at week 4 (mean (SD); Dysport, 49 (29)%; Botox, 44 (28)%). A similar response profile was seen for other assessments ofefficacy. The duration of effect, assessed by time to retreatment, wasalso similar (mean (SD); Dysport, 83.9 (13.6) days; Botox, 80.7 (14.4)days; p=0.85). During the study 22 of 38 (58%) Dysport patientsreported 39 adverse events, and 24 of 35 (69%) Botox patients reported56 adverse events (p=0.35). A global assessment of efficacy and safetyconsidered that 29 of 38 (76%) Dysport patients and 23 of 35 (66%)Botox patients were treatment successes (p=0.32).
CONCLUSION—Patients with predominantly rotationalcervical dystonia treated with the clinically indicated dose of Botoxor three times that dose in Dysport units show similar improvements anddo not have significantly different safety profiles.
相似文献
48.
MY Mancao LJ Sindel PH Richardson FM Silver 《Acta paediatrica (Oslo, Norway : 1992)》1996,85(1):118-120
Croup is an acute infectious illness usually occurring in children; it is characterized by brassy cough and stridor. The main pathogens include mainly parainfluenza and influenza viruses. Recently there have been reports of prolonged croup caused by the herpes simplex viruses. We report two cases of prolonged croup due to herpes simplex types 1 and 2. We also review and summarize the reported pediatric cases of herpetic croup. 相似文献
49.
50.
J. Blasi G. Egea M. J. Castiella M. Arribas C. Solsona P. J. Richardson J. Marsal 《Journal of neural transmission (Vienna, Austria : 1996)》1992,90(2):87-102
Summary Torpedo electric organ has been used to study the binding of botulinum neurotoxin type A to pure cholinergic synaptosomes and presynaptic plasma membrane.125I-labeled botulinum neurotoxin type A exhibits specific binding to cholinergic fractions. Two binding sites have been determined according to data analysis: a high affinity binding site (synaptosomes: Kd=0.11±0.03 nM, Bmax=50±10 fmol · mg prot–1; presynaptic plasma membrane: Kd=0.2±0.05 nM, Bmax=150±15 fmol · mg prot–1) and a low affinity binding site (synaptosomes: Kd 26 nM, Bmax 7.5 pmol · mg prot–1; presynaptic plasma membrane: Kd 30 nM, Bmax 52 pmol · mg prot–1). The binding of125I-botulinum neurotoxin type A is decreased by previous treatment of synaptosomes by neuraminidase and trypsin, and by a preincubation with bovine brain gangliosides or antiserum raised against Torpedo presynaptic plasma membrane. When presynaptic plasma membranes are blotted to nitrocellulose sheet, either125I-botulinum neurotoxin or botulinum toxin-gold complexes bind to a Mr 140,000 protein. Botulinum toxin-gold complexes have also been used to study the toxin internalization process into Torpedo synaptosomes. The images fit the three step sequence model in the pathway of botulinum neurotoxin poisoning. 相似文献