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991.
An attempt was made to explore the possibility of using the masticatory muscle reflexes as pain indices in human subjects. It was found that the digastric reflex, so readily evoked by electrodental stimulation in experimental animals, could not be consistently elicited in man. The reflex silent period of the masseteric muscles, on the other hand, may be used as a pain index for evaluating dental analgesia, provided that analgesic interference is anticipated at points along the reflex arc. 相似文献
992.
Humphreys K Al Badri S Kinirons M Welbury RR Cole BO Bryan RA Campbell O Fung DE 《Pediatric dentistry》2003,25(5):475-478
PURPOSE: The objectives of the present study were to determine the prevalence of residual extrusion, pulpal necrosis, and resorption for extruded permanent teeth and to establish the effect of presentation and treatment factors. METHODS: Seventy-two traumatically extruded permanent incisors were studied at the Departments of Paediatric Dentistry in Belfast, Newcastle upon Tyne, and Glasgow. The mean age of the patients was 10.1 years (range=6 to 18 years). Clinical and radiographic outcomes were analyzed and related to presenting and treatment factors. RESULTS: The initial degree of extrusion was moderate for 46 teeth (64%), and the median delay prior to repositioning was 3 hours (range=1 to 168 hours). Pulp necrosis occurred in 31 teeth (43%), residual extrusion was present in 16 teeth (23%), and inflammatory resorption occurred in 11 teeth (15%). Residual extrusion was significantly associated with a delay in repositioning the tooth, pulpal necrosis was significantly more common in teeth with closed apices and in severely extruded teeth, and inflammatory resorption was more common after pulpal necrosis. CONCLUSIONS: Residual extrusion could be minimized by earlier presentation and repositioning. The risk of pulpal necrosis is greatest for severely extruded teeth and for those with closed apices. 相似文献
993.
The duration of the masseteric EMG silent period as induced by tapping on the chin was measured at different levels of sustained bite force. Under both open bite and normal occlusion, the duration of the silent period was inversely related to the magnitude of the bite force. For bite force of the same magnitude, the value of the silent period remained relatively constant for the same subject in different trials (SEM ? 1 per cent), whereas the absolute values of the silent periods ranged far and wide for different individuals even under similar experimental conditions. 相似文献
994.
995.
Evaluating Efficacy and Safety of Combination Medication of Atorvastatin and a Herbal Formula Containing Salvia miltiorrhiza and Pueraria lobata on Hyperlipidemia 下载免费PDF全文
Pui‐Han Wong Ka‐Chun Yau Elaine Wat Angela Sze‐Man Hung Yan‐Ping Wang Kit‐Man Lau Chun‐Hay Ko Judy Yuet‐Wa Chan Mary Miu‐Yee Waye Kwok‐Pui Fung 《Phytotherapy research : PTR》2017,31(10):1579-1589
Despite being a potent hypolipidemic drug, atorvastatin (AS) possesses certain adverse effects. Using AS and an herbal formula (Danshen and Gegen, DG) in combination may achieve potentiated hypolipidemic effects and also reduce its adverse effects. Hence, this study aimed to investigate the efficacy and safety of an AS and DG combination on high‐fat diet‐induced hyperlipidemia. Treatment outcomes were assessed by measuring parameters including body weight, adipose tissue, liver, total cholesterol, triglyceride, and low‐density and high‐density lipoprotein cholesterol. Measurements of adverse effects were achieved by determining aspartate aminotransferase (AST), alanine transaminase (ALT), and creatine kinase (CK). Danshen and Gegen, as well as AS alone, reduced body weight, adipose tissue, liver weight, liver fat vacuoles, total liver lipids, total cholesterol, triglyceride, low‐density lipoprotein cholesterol, and high‐density lipoprotein cholesterol in high‐fat diet‐fed mice but increased AST, ALT, and CK. A combination of AS and DG was able to enhance reduced effects on the aforementioned parameters in relation to hyperlipidemia over AS or DG alone. It also reduced the elevation of AST, ALT, and CK induced than by AS or DG alone. Results demonstrated that an AS and DG combination resulted in stronger hypolipidemic effects than with AS or DG alone. Additionally, DG might attenuate adverse effects of AS on the liver and skeletal muscle. Copyright © 2017 John Wiley & Sons, Ltd. 相似文献
996.
John V Messer LB Arora R Fung S Hatzis E Nguyen T San A Thomas K 《Australian dental journal》1999,44(4):259-267
Child abuse is a disturbingly common finding in society today. In view of the high proportion of orofacial injuries seen in victims of child abuse, dentists are in a strategic position to recognize and report suspected cases. The present study of 347 dentists in Victoria, Australia, assessed the level of knowledge and attitudes among dental professionals on the important issue of child abuse. While a high level of interest was shown by the participants towards this issue, a need for further information and training in the recognition and reporting of child abuse was seen in the survey findings. While dentists at present are not legally mandated in all states of Australia to report suspected cases of child abuse, the dental profession is in a key position to play an active role in the identification and reporting of this substantial community problem. 相似文献
997.
It has been suggested that due to its vasoconstrictive action, nicotine may have a deleterious effect on the periodontium. This study examined the effects of topical and systemic nicotine administration on gingival blood flow. Eighteen young adult dogs were divided into three groups receiving the following treatments for 28 days; topical nicotine in orabase, systemic nicotine via osmotic mini-pumps, and topical orabase or systemic saline via osmotic mini-pumps. Blood flow to the gingiva was measured (at days 0 and 28) by the radiolabeled microsphere method. Blood flow was consistently increased from day 0 to day 28 in the nicotine-treated animals. Comparison of days 0 and 28 blood-flow values demonstrated a statistically significant change (p less than 0.05) in the anterior regions of the topical-nicotine group as compared with the control group. The increased flow may be a reflection of the mode of nicotine delivery and timing of the blood-flow determination procedures. 相似文献
998.
Tak Yeung Leung Lin Wai Chan Lai Wa Law Daljit Singh Sahota Tak Yuen Fung Tse Ngong Leung 《The journal of maternal-fetal & neonatal medicine》2013,26(4):300-304
Objective.?To examine the effectiveness of first trimester fetal Trisomy 21 (T21) screening using a combination of maternal age, nuchal translucency, maternal serum levels of free β-hCG and PAPP-A in a predominantly Chinese population in Hong Kong.Methods.?Consecutive women who underwent the combined screening for T21 between 11 and 13 + 6 weeks of gestation between 2003 and 2007 were recruited. Risk of T21 was calculated using Fetal Medicine Foundation algorithm and karyotyping was advised when the risk was 1:300 or above. All women were followed up for pregnancy and fetal outcome.Results.?10,363 fetuses underwent screening. 99% of the women were Chinese and 27.4% were at or above 35 years old. 618 fetuses were screened positive (5.9%), which included 31 cases of T21, 14 cases of T18, 7 cases of T13, 10 cases of 45XO and 7 cases of other chromosomal abnormalities. Among the 9745 screened negative fetuses all but 50 (0.5%) had a known outcome, which included three T21 and four other chromosomal abnormalities. All were subsequently identified at the morphology scan except for one case of T21. The detection rate and false positive rates for T21 were 91.2% and 5.4%, respectively and the positive predictive value for all chromosomal abnormalities was 1 in 9.Conclusions.?Combined screening for T21 is highly effective among Chinese women. Training, quality control, regular auditing and follow up are essential to maintain screening standards. 相似文献
999.
1000.
Antonovich DD Berke A Grant-Kels JM Fung M 《Journal of the American Academy of Dermatology》2004,50(2):315-318
Neutrophilic eccrine hidradenitis is a nonspecific clinical reaction pattern classified as a neutrophilic dermatosis that typically occurs in the setting of chemotherapy for hematologic malignant disease. Neutrophilic eccrine hidradenitis more rarely has been reported in association with infectious agents, including Serratia, Enterobacter, Staphylococcus, and HIV. We describe the first case of infectious eccrine hidradenitis occurring in a patient with cutaneous Nocardia infection. 相似文献