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71.
A number of idiopathic, pathological and pharmacological reactions may result in an overgrowth of the gingiva. This review concentrates on those overgrowths associated with various pharmacological agents. The pharmacokinetics and side effects of each drug associated with gingival overgrowth are discussed along with the clinical and histological features and treatment. By examining the possible pathogeneses for these overgrowths we propose a unifying hypothesis for the causation based around inhibition of apoptosis and decreased collagenase activity modulated by cytoplasmic calcium.  相似文献   
72.
The facial nerve conduction velocity was measured in 30 healthy subjects (60 sides) and in 51 patients with a unilateral Bell's palsy. The normal value was 47.8 ± 5.1 m/s. Incomplete recovery was common in Bell's palsy when the velocity was below 30 m/s. Mild synkinesis was observed in only one patient when the nerve conduction velocity was above 30 m/s. When the degree of degeneration revealed by electroneuroneography did not exceed 60%, the conduction velocity was in the normal range. For degrees of degeneration in excess of this, the conduction velocity decreased in parallel with the increase in the degree of degeneration.  相似文献   
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OBJECTIVE: We have used the combination of midazolam, a short-acting benzodiazepine, and ketamine, a "dissociative anesthetic," to provide conscious sedation for invasive or lengthy procedures. METHODS: A total of 350 procedures (74 lumbar punctures, 97 bone marrow aspirations or biopsies, 84 radiotherapy sessions, and 95 imaging studies) were performed on 68 children, 4 months to 17 years of age, in both inpatient and ambulatory settings. All patients had an intravenous line in place and were monitored for heart rate and O2 saturation by pulse oximetry for the duration of the procedure and recovery time. Blood pressure was monitored periodically (every 5 to 30 minutes). Oxygen and suction equipment was available during the procedure. In addition to the individual performing the procedure, a second staff member trained in airway management (eg, physician, nurse practitioner, or registered nurse) was present to monitor vital signs and respiratory status. Patients were sedated initially with midazolam (0.05 to 0.1 mg/kg intravenously; maximum single dose of 2 mg, maximum total dose of 4 mg), followed by ketamine (1 to 2 mg/kg intravenously). During lengthy procedures, additional doses of ketamine (0.5 to 1 mg/kg) were given as necessary. Effectiveness of the sedation, recovery time, and adverse events associated with the sedative regimen were documented. RESULTS: All patients were effectively sedated with this regimen. Four patients experienced transient decrease in O2 saturation (<85%) requiring temporary interruption of the procedure and oxygen by blow-by; the procedure was subsequently completed without incident in each case. Two patients experienced significant agitation during recovery from sedation. This side effect resolved spontaneously after 5 to 10 minutes in one patient and was effectively treated with diphenhydramine hydrochloride in the other. Twenty-four lumbar punctures were associated with transient decrease in O2 saturation (88% to 92%), which improved by relief of neck flexion and/or blow-by oxygen. No hypotension, bradycardia, or respiratory depression requiring respiratory support or reversal of sedation was noted. Anesthesia recovery time ranged from <15 minutes to 120 minutes with >70% of patients recovering within 30 minutes. Most patients demonstrated an increase in oral secretions requiring occasional suctioning. Transient sleep disturbances were reported in only two patients. CONCLUSIONS: This sedative regimen of intravenous midazolam and ketamine was found to be safe and effective. Its use has greatly reduced patient and parent anxiety for diagnostic and therapeutic procedures.  相似文献   
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目的:探讨过氧化物酶体增殖物激活型受体γ(PPARγ)及其配体(15-脱氧-前列腺素J2,15-d-PGJ2)对细胞滋养细胞表达基质金属蛋白酶-2(MMP-2)和MMP-9的调控作用。方法:采用免疫荧光细胞化学方法检测细胞滋养细胞中PPARγ的表达;利用免疫荧光共聚焦技术观察15-d-PGJ2作用前后细胞滋养细胞MMP-2和MMP-9表达强度的变化;通过荧光定量PCR(Real-timePCR)和Westernblot方法定量检测MMP-2和MMP-9mRNA和蛋白的表达变化。结果:在细胞滋养细胞中有PPARγ蛋白表达,且主要定位在细胞滋养细胞核中;15-d-PGJ2作用后细胞滋养细胞中MMP-2和MMP-9的表达明显下降,与对照组相比差异显著(P<0.01);15-d-PGJ2对MMP-2的作用强于MMP-9。结论:PPARγ及其配体15-d-PGJ2调节滋养细胞浸润作用可能是通过调节MMP-2和MMP-9的表达实现的。  相似文献   
77.
目的:确定胬肉下浸润麻醉联合个体化的结膜切口在翼状胬肉逆行切除联合自体角膜缘干细胞移植手术中的疗效.方法:采用胬肉下浸润麻醉联合个体化的结膜切口在翼状胬肉逆行切除联合自体角膜缘干细胞移植手术方式对108例(128眼)胬肉患者实施手术治疗.其中男46例(60眼),女62例(68眼);年龄29~77岁,其中复发胬肉12眼,鼻侧胬肉124眼,颈侧胬肉4眼,侵入角膜2~6 mm;病程最短的1.5年,最长的40年,从事户外工作者80例,其它28例.结果:术后3d内患眼有不同程度的红、异物感、流泪症状,1~3d角膜上皮愈合,移植片均存活,1周左右水肿消退.随访观察半年至3年,1眼复发,复发率为0.93%.均无睑球粘连、眼球活动受限等出现.无植片排斥、融解现象.原取瓣区之角膜缘未见因取瓣而引起的角膜新生血管及浑浊变性和结膜增生入角膜等手术并发症.并有15例(17眼)视力有不同程度提高.结论:胬肉下浸润麻醉和个体化的结膜切口在逆行胬肉切除手术中有其突出的优点,手术更彻底、副损伤非常少,手术时间短,且具有复发率低、治愈率高的优点,值得推广应用.  相似文献   
78.
特应性皮炎(AD)是一种常见的慢性反复性炎症性皮肤疾病.遗传因素是特应性皮炎发生、发展的重要因素.丝聚蛋白基因(FLG)被定位于人类染色体1q21的EDC区域内,该基因发生突变后导致丝聚蛋白功能缺失进而皮肤屏障发生破坏,与AD的发生密切相关.研究表明,不同种族和不同区域间AD患者FLG基因突变位点可能不同.FLG基因突变与AD发病关系的研究有利于进一步加深对AD发病机制的认识,并可能为AD的治疗提供新的方向.  相似文献   
79.
Polycyclic aromatic hydrocarbons (PAHs) are formed during incomplete combustion. Domestic wood burning and road traffic are the major sources of PAHs in Sweden. In Stockholm, the sum of 14 different PAHs is 100-200 ng/m(3) at the street-level site, the most abundant being phenanthrene. Benzo[a]pyrene (B[a]P) varies between 1 and 2 ng/m(3). Exposure to PAH-containing substances increases the risk of cancer in humans. The carcinogenicity of PAHs is associated with the complexity of the molecule, i.e., increasing number of benzenoid rings, and with metabolic activation to reactive diol epoxide intermediates and their subsequent covalent binding to critical targets in DNA. B[a]P is the main indicator of carcinogenic PAHs. Fluoranthene is an important volatile PAH because it occurs at high concentrations in ambient air and because it is an experimental carcinogen in certain test systems. Thus, fluoranthene is suggested as a complementary indicator to B[a]P. The most carcinogenic PAH identified, dibenzo[a,l]pyrene, is also suggested as an indicator, although it occurs at very low concentrations. Quantitative cancer risk estimates of PAHs as air pollutants are very uncertain because of the lack of useful, good-quality data. According to the World Health Organization Air Quality Guidelines for Europe, the unit risk is 9 X 10(-5) per ng/m(3) of B[a]P as indicator of the total PAH content, namely, lifetime exposure to 0.1 ng/m(3) would theoretically lead to one extra cancer case in 100,000 exposed individuals. This concentration of 0.1 ng/m(3) of B[a]P is suggested as a health-based guideline. Because the carcinogenic potency of fluoranthene has been estimated to be approximately 20 times less than that of B[a]P, a tentative guideline value of 2 ng/m(3) is suggested for fluoranthene. Other significant PAHs are phenanthrene, methylated phenanthrenes/anthracenes and pyrene (high air concentrations), and large-molecule PAHs such as dibenz[a,h]anthracene, benzo[b]fluoranthene, benzo[k]fluoranthene, and indeno[1,2,3-cd]pyrene (high carcinogenicity). Additional source-specific indicators are benzo[ghi]perylene for gasoline vehicles, retene for wood combustion, and dibenzothiophene and benzonaphthothiophene for sulfur-containing fuels.  相似文献   
80.
OBJECTIVES: Associations between shift work, chronic psychosocial work stress, and 2 important cardiovascular risk factors, hypertension and atherogenic lipids were studied.The hypothesis was tested that psychosocial work stress, as defined by the model of effort-reward imbalance, mediates the effects of shift work on cardiovascular risk. METHODS: Altogether 2288 male participants aged 30-55 years in the baseline screening of the Swedish WOLF (work organization, lipids, and fibrinogen) study underwent a clinical examination and answered a standardized questionnaire measuring shiftwork schedules, effort-reward imbalance at work, and health-adverse behavior. RESULTS: In addition to the direct effects of shift work on cardiovascular risk, mediating effects of effort-reward imbalance at work were found. The respective odds ratios (OR) ranged from 2.18 to 2.27 for hypertension and from 1.34 to 1.45 for atherogenic lipids. While the effects remained significant after extensive confounder control concerning hypertension, part of the observed effect on atherogenic lipids was due to behavioral influences. CONCLUSIONS: Despite obvious limitations, the results indicated that a stressful psychosocial work environment acts as a mediator of health-adverse effects of shift work on hypertension and, partly, atherogenic lipids. In terms of occupational health the findings call for a more comprehensive assessment of the health risks associated with shift work.  相似文献   
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