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91.
92.
K. W. Stephen J. I. Russell S. L. Creanor C. K. Burchell 《Community dentistry and oral epidemiology》1987,15(2):90-94
Fibre optic transillumination (FOTI) has been employed during the course of a 3-yr clinical dentifrice trial which initially involved 3003 children. At the initial examination, a subgroup of 813 13-yr-olds, and at the following annual visit, 2247 14-yr-olds, were examined using a 150 W lamp and 0.5 mm diameter probe. Routine clinical and radiographic examinations were performed separately. Compared to the clinical scores for anterior teeth, FOTI detected an additional 64% of interproximal lesions at the first visit while, for the larger number of children at the second visit, the increase in lesion detection level using FOTI was 37%. For the posterior teeth the comparable figure at the second examination was 92%. When FOTI data were compared to radiographic data for more than 52,000 posterior interproximal surfaces, FOTI could only detect 17% of radiographic Grade 2 lesions and 48% Grade 3 lesions. Thus any assumption that FOTI diagnoses may be a substitute for bitewing radiography appears premature. 相似文献
93.
Abstract – The dental records made on presentation of 1367 consecutive patients (731 females and 636 males) for orthodontic treatment at a private orthodontic practice between 1998 and 2002 were examined for data relating to trauma to the permanent incisors. The results showed that 10.3% of these patients had suffered from dental trauma before the onset of orthodontic treatment. The highest prevalence of dental trauma was determined in the 11–15 years age group, corresponding to the dental developmental stage of the late mixed dentition. The most frequently affected teeth were the maxillary central incisors (79.6%), and the most common types of trauma were fracture of enamel–dentin without pulpal involvement (42.7%) and fracture of enamel (33.8%). Compared to patients with normal overjet and adequate lip coverage, the frequency of dental trauma was significantly higher in patients with increased overjet and adequate lip coverage ( P = 0.028) or with increased overjet and inadequate lip coverage ( P = 0.003). The results of the present study indicate that a significant percentage of candidates for orthodontic treatment, and especially those with increased overjet and inadequate lip coverage, suffer trauma to their permanent incisors before the onset of orthodontic treatment. It might also be concluded that preventive orthodontic treatment of such patients should be initiated and completed before the age of 11, i.e. in the early to middle mixed dentition. 相似文献
94.
目的:比较不锈钢K锉常规根管预备(SSPT)法与镍钛机用根管器械逐步深入预备(NRPT)法在磨牙根管治疗中的近期临床效果和成本/效果(C/E)值。方法:入选患者随机分为SSPT法(49例)和NRPT法(45例)2组,记录治疗后不良反应、补救治疗措施和所花费用,评价近期疗效并进行成本-效果分析,用SPSS11.5统计分析软件进行数据统计。结果:NRPT组治疗满意率优于SSPT组(P=0.034),但前者人均治疗成本显著高于后者(P=0.001)。对重度弯曲根管,NRPT组治疗满意率优于SSPT组(P=0.007);前者的C/E值较后者低394.52元;轻中度弯曲根管前者的C/E值较后者高192.04元。根尖正常患者,NRPT组治疗满意率高于SSPT(P=0.012),但前者C/E值比后者高32.32元;而根尖阴影患者NRPT组的C/E值较SSPT组高376.47元。结论:NRPT法的疗效优于SSPT法,但治疗成本较高;对重度弯曲根管患牙,NRPT法可使患者受益;对中轻度弯曲根管患牙,应选用SSPT法。对根尖正常的患者,NRPT法近期疗效更高,而治疗前有根尖病变的患者,SSPT法可节约治疗成本。 相似文献
95.
Mariana Villarroel Dorrego Paul M. Speight A. William Barrett 《Journal of oral pathology & medicine》2006,35(5):268-273
BACKGROUND: CD40 has a role in the regulation of immune responses, cell proliferation and migration, and apoptosis. Little is known of its distribution in oral mucosal pathology. METHODS: Oral keratinocyte lines were tested for CD40 protein by Western blotting. Immunohistochemistry was used to stain paraffin sections of oral mucosa in health and in inflammatory, reactive, dysplastic and malignant disease. RESULTS: Western blotting confirmed the presence of CD40 in oral keratinocytes. CD40 was generally expressed by keratinocytes in the basal layer, with variable parabasal expression. Langerhans cells also stained positively. Expression was lost in nine of 33 (27%) epithelial dysplasias, seven of which were severe. Eighty-one percent of well, 69% of moderately and 50% of poorly differentiated oral squamous cell carcinomas (OSCC) expressed CD40. Overall, 45 of 65 (69%) OSCC were positive. The pattern of expression was unrelated to tumour differentiation. CONCLUSION: CD40 expression by basal and parabasal oral keratinocytes is physiological. Expression is lost in approximately one-third of oral epithelial dysplasias and OSCC. The significance of such loss remains unknown, but may be related to immunological or other abnormalities of keratinocyte homeostasis. 相似文献
96.
微波干燥法对腊叶标本压制的实验研究 总被引:2,自引:1,他引:1
目的:寻求一种不受气候条件影响而能成功制作腊叶标本的新技术。方法:采用微波干燥法,即用微波炉,由创制的直径31cm瓦楞纸板、吸水纸与玻璃皿组成的压制程序进行微波干燥。结果:微波干燥法可用于腊叶标本压制,且优于传统的常规腊叶标本压制方法。结论:本研究为腊叶标本的制作提供了一个新方法,收到了便捷、高效、且保色的理想效果。 相似文献
97.
离体肺组织切片的制备和孵育 总被引:1,自引:0,他引:1
目的建立一种简便有效的离体肺组织切片孵育方法。方法利用肺组织精细切片技术制备肺组织切片 ,以 0 .5mLKrebs Henseleit(K H)缓冲液作为孵育液 ,在 37℃培养箱内分别孵育 1、2、3、4h ,测定肺片的四甲基偶氮唑盐 (MTT)比色、乳酸脱氢酶 (LDH)释放率和三磷酸腺苷 (ATP)含量 ,以反映肺组织活性。结果肺片在 37℃培养箱内孵育 1、2、3、4h后MTT比色、LDH释放率和ATP含量均无统计学差异 (P >0 .0 5 )。结论应用 0 .5mLKrebs Henseleit(K H)缓冲液作为孵育液、在 37℃培养箱对肺片进行孵育时组织活性没有明显变化 ,可作为一种简便有效的孵育方法用于离体肺片研究 相似文献
98.
Previously reported attenuation of skin postural vasoconstriction in women during the luteal menstrual cycle phase may be
due to a progesterone-mediated decrease in myogenic or veno-arteriolar (VAR) mechanisms. Skin perfusion was measured in the
shin and foot dorsum by Laser Doppler Fluxometry during leg dependency that increased vascular transmural pressure below (myogenic
constriction only) and above (myogenic and VAR) the 25 mmHg threshold for activation of the VAR, and during venous distension
to activate the VAR alone (cuff inflation to 50 mmHg). In six young women with normal menstrual cycles, vasoconstrictor responses
to all interventions did not differ between days 7–13 (follicular) and 18–23 (luteal) of the normal menstrual cycle when progesterone
levels were low and at their peak respectively. In eight women taking combined oral contraceptives (OC) and tested during
pill consumption days, reductions in foot skin perfusion were smaller (P = 0.05) than in the luteal phase of the normal cycle for leg dependency below (−36.9 ± 5.2% OC vs. −52.5 ± 7.8% luteal, mean ± S.E.M.)
and above (−43.7 ± 3.4% OC vs. −55.1 ± 4.8% luteal) the VAR threshold, and for venous distension (−53.1 ± 2.6% OC vs. 66.4 ± 5.5%
luteal). In women with normal menstrual cycles, impaired postural vasoconstriction may be confined to those who experience
pre-menstrual symptoms rather than a direct effect of endogenous hormones. Reduced vasoconstriction in the dependent foot
during OC use is consistent with the known vasodilator action of exogenous hormones and its long-term effects 相似文献
99.
Correction by oral adsorbent of abnormal digestive tract milieu in rats with chronic renal failure 总被引:1,自引:1,他引:0
In order to examine the mechanism by which the oral carbonaceousadsorbent, AST-120 delays the appearance of glomerular sclerosis,experiments were carried out in 120 male Sprague-Dawley ratsweighing 285320 g. The rats were first subjected to 2/3,3/4, and 4/5 nephrectomy (n=40). The experiments were begunat 2 weeks after the surgery, and were performed over an 8-weekperiod. Half of each group (n=20) was administered 1 g/day ofliquid AST-120, and the other half received liquid vehicle solutionwith pair feeding in each group. In the 2/3 nephrectomized groupthe administration of AST-120 delayed the occurrence of glomerularhypertrophy and prevented the appearance of glomerular sclerosiswithout any significant differences in renal function, systemicblood pressure (SBP), and urinary protein excretion (U-P). Inthe 3/4 nephrectomized group the administration of AST-120 delayedthe appearance of glomerular hypertrophy and sclerosis withsignificant decreases in SBP and U-P. In the 4/5 nephrectomizedgroup the administration of AST-120 delayed the appearance ofglomerular sclerosis and prevented a decrease in renal function.It is concluded that administration of the oral adsorbent AST-120delays the occurrence of glomerular sclerosis by delaying theappearance of glomerular hypertrophy, systemic hypertension,and the increase in proteinuria. It can be therefore mentionedthat the accumulating substances in the digestive tract worsenthe abnormal milieu of chronic renal failure. 相似文献
100.
目的探讨中药复方地甘口服液(DGOL)对辐射损伤小鼠脾细胞凋亡及凋亡相关基因bcl-2和bax mRNA表达的作用.方法建立辐射损伤模型(一次性7.0Gy的X射线照射),喂饲100%地甘口服液每次0.2 ml/10 g小鼠,每日2次.第10天用原位末端标记的TUNEL技术检测脾组织细胞凋亡和原位杂交法检测凋亡相关基因bcl-2和bax mRNA的表达.结果地甘口服液组与对照组比脾脏的细胞凋亡率和bax mRNA表达显著减少(P<0.01),bcl-2 mRNA的表达显著增强(P<0.01).结论中药复方地甘口服液可能通过促进bcl-2和降低bax mRNA的表达,促进造血细胞的增生,提高机体免疫力. 相似文献