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21.
In vivo and in vitro study of the effects of chlorpromazine on tooth mineralization in rats and mice
Akifumi Togari Makoto Kondo Michitsugu Arai Shosei Matsumoto 《Archives of oral biology》1993,38(12):1065-1070
The effects of chlorpromazine (CPZ) on tooth mineralization were examined using incisor dentine in adult rats and cultured tooth germs of mandibular first molars dissected from mouse embryos. CPZ (10, 50 and 250 mg/kg, s.c.) substantially inhibited dentine mineralization as evaluated by contact microradiographs. Plasma calcium and phosphorus concentrations were not decreased by CPZ (10 and 50 mg/kg). Physicochemical effects were not involved in the action of CPZ on the mineralization. In vitro experiments showed that CPZ (1 and 10 μM) inhibited mineralization and alkaline phosphatase (ALP) activity in the tooth germs. As CPZ has the properties of a calmodulin antagonist, the calmodulin antagonists W-7 and W-5 were also examined. Both inhibited mineralization and ALP activity in tooth germs; W-5 had less effect than W-7. These in vivo and in vitro findings suggest that CPZ inhibited cell-mediated mineralization in dentine without affecting the calciumdashregulating system and physicochemical mineral deposition. In addition, calmodulin could be involved in cell-mediated mineralization. 相似文献
22.
L.F. Del Castillo R. Schlegel Gómez M. Pelka O.P. Hornstein A.C. Johannessen P. von den Driesch 《Journal of periodontal research》1996,31(1):36-42
The β1-integrins (VLA family) are cellular adhesion molecules (CAM) that play a major role in cell-cell and cell-matrix interactions. The expression pattern of CAM was studied in 5 clinically normal volunteers with healthy gingiva and in 18 patients with clinically different stages of periodontitis. In healthy human gingiva α2. α3 and α6 integrin chains were found in a characteristic distribution, showing a broad continuous expression on the junctional and sulcular epithelium sites. The expression of these integrins was demonstrated primarily on the basal cell layers and in some cells of the stratum spinosum. Inflammatory stages of periodontitis revealed further upregulation of α2, α3 and α6 integrins into the junctional and sulcular epithelial cells, which correlated with the stage of the periodontitis and the extent of the cellular infiltration. α4 and α6 were found to be the predominant β1 integrin chains on inflammatory cells. The amount of δ4 and ş6 positive infiltrative cells increased with the number of inflammatory cells. VCAM-1. the corresponding cell-cell ligand of VLA-4 (α4) was present on the majority of subepithelial vessels in all stages of gingivitis and periodontitis. The α5 subunit was expressed on both endothelium and gingival connective tissue cells. Samples from advanced periodontitis cases showed a higher number of a5 positive mononuclear cells. In comparison to normal epidermis, a human gingival epithelial cells express higher levels of integrins. This expression is further upregulated in advanced stages of periodontitis, indicating changes of the β1 integrin organization. 相似文献
23.
C. Y. Wu-Wang S. -L. Wang M. Brigham A. Correa A. Slomiany B. L. Slomiany 《Archives of oral biology》1993,38(12):1045-1050
Adult male Syrian hamsters were treated by swabbing the apex of the buccal pouch with corn oil (control, C), 1 mM benzo(a)pyrene (BP), nicotine (NC), or BP + NC in corn oil, twice daily, 5 days a week. After a 4-week treatment, the pouches and submandibular glands were dissected and used for the determination of endogenous prostaglandin (PG) production and studies on in vitro PG synthesis. Of the three PGs analysed (PGE2, PGF2 and 6-keto-PGF1), PGE2 was predominant in the pouch and the glands. BP or NC alone had only a weak effect on PG synthesis in both tissues. However, the combination of BP and NC had a synergistic effect, causing diminished PG synthesis in both tissues. In buccal pouch, BP + NC significantly decreased the concentrations of endogenous PGE2 and PGF2 (PGE2: 0.669 + 0.254 versus 1.698 + 0.460, PGF2: 0.273 ± 0.090 versus 0.625 ± 0.272 ng/g tissue; BP + NC versus C; mean ± SD, n = 5, p < 0.05). Similarly significant results were also found for in vitro PG synthesis (PGE2: 0.541 ± 0.249 versus 1.399 ± 0.340, PGF2: 1.045 ± 0.428 versus 2.133 ± 0.510 ng/g tissue; BP + NC versus C; mean ± SD, n = 5, p < 0.05). In submandibular glands, BP + NC significantly diminished the concentration of endogenous PGE2 (1.183 ± 0.175 versus 2.379 ± 0.488 ng/g tissue; BP + NC versus C; mean ± SD, n = 5, p < 0.05). The synthesis of 6-keto-PGF1 in both tissues, and the synthesis of PGF2 in submandibular gland, were slightly decreased with all treatments. 相似文献
24.
Y. Tsukamoto S. Fukutani T. Shin-ike T. Kubota S. Sato Y. Suzuki M. Mori 《Archives of oral biology》1992,37(12):1045-1055
Pulp fibroblasts were isolated from human deciduous and supernumerary teeth and cultured in vitro. With continued culture in normal tissue-culture medium, six pulp fibroblast strains formed cell nodules after 10–15 days. By electron microscopy the nodules had matrix vesicles, and needle-shaped crystals associated with a dense network of collagen fibrils. The crystalline material exhibited a pattern consistent with hydroxyapatite when nodules were examined by X-ray diffractometry. Furthermore, the cells showed high levels of alkaline phosphatase activity, which could be increased more than seven-fold by the addition of 1,25(OH)2D3 (5 × 10−9−5 × 10−8M). In addition to the production of type I collagen, these cells also synthesized fibronectin and osteonectin. The formation of mineralized tissue nodules by pulp cells in vitro provides a useful system for study of the pathological calcification of pulp tissues. 相似文献
25.
重症肌无力(MG)是一种神经-肌肉接头传递功能障碍的自身免疫性疾病。MG的发病机制主要涉及免疫因素和遗传因素。免疫因素包括多种致病抗体、细胞免疫、细胞因子、补体及胸腺等。随着免疫学研究的不断进展,MG的发病机制也有了更深入的研究。 相似文献
26.
目的:探索一种保留育龄期孕前患者哺乳功能的乳头内陷矫正方法。方法:临床纳入乳头内陷程度为Ⅰ型、Ⅱ型的孕前育龄患者各60例,随机分为Ⅰ型手术组、Ⅰ型对照组、Ⅱ型手术组及Ⅱ型对照组各30例。手术组孕前进行手术,并佩戴矫正器6个月,对照组不予手术处理。同时以乳头发育正常的30例孕前育龄者作为正常组。纳入成功妊娠、生产并尝试哺乳患者,统计乳头高度,母乳喂养情况,乳头皲裂及乳腺炎的发生情况。结果:对于Ⅰ型和Ⅱ型患者,手术组术后即刻及孕晚期,其乳头高度相对术前及对照组均有显著性改善(P0.01),母乳喂养4个月成功率显著提高(P0.05),乳头皲裂和乳腺炎的发生率显著降低(P0.05),且除Ⅱ型患者的术后乳头高度外,与正常组比较差异无统计学意义(P0.05)。结论:对于Ⅰ型及Ⅱ型乳头内陷,佩戴乳头内陷矫正器除可增加乳头高度外,可在保留哺乳功能的同时,降低产后乳头皲裂和乳腺炎发生率。 相似文献
27.
目的探讨输血治疗是否是老年股骨粗隆间骨折围手术期隐性失血量的影响因素,并为是否需要输血治疗提供参考。方法回顾性分析2009年3月至2012年10月期间接受股骨近端防旋髓内钉(proximal femoral nail anti-rotation,PFNA)内固定手术的176例老年股骨粗隆间骨折患者的临床相关资料,依据是否接受输血治疗将患者分为输血组(56例)及未输血组(120例),对两组患者术前、术后血常规指标以及根据Gross线性方程计算得到的总失血量、隐性失血量进行分析,比较输血治疗对隐性失血量的影响。结果输血组平均隐性失血量为353.0 mL,占平均总失血量比例为83.1%,未输血组患者平均隐性失血量为427.0 mL,占总失血量比例为84.6%。两组平均隐性失血量相比,有统计学意义(P0.05),平均隐性失血量占总失血量比例,两组比较无统计学意义(P0.05)。结论输血治疗能减少围手术期隐性失血量,但并不能降低老年粗隆间骨折的隐性失血量占总失血量的比例,术后应根据红细胞压积(hematocrit,Hct)及血红蛋白量(hemoglobin,Hb)的变化,合理选择输血治疗,减少并发症的产生。 相似文献
28.
国医大师薛伯寿在临床应用《内经》"木郁达之"之法治疗内科疾病常获显效,以三例医案胃脘痛、小儿反复呼吸道感染及咳嗽为基础,探讨和分析"木郁达之"治则的重要性及其在临床上的应用。薛老推崇《内经》"木郁为先""木郁为重",认为木郁是常见的发病病因和病机,"木郁达之"为中医重要治法,对指导临床实践具有重要的意义。 相似文献
29.
Ann Harrison PhD 《Journal of pain and symptom management》1991,6(8):466-475
The aims of the present study were to characterize the childbirth experiences of three groups of Arab mothers delivering in Kuwait and to evaluate the use of visual analog scales (VAS) for assessing their pain (N = 301). Kuwaiti, Palestinian, and Bedouin women who were expected to have an uncomplicated vaginal delivery were studied. 73% of the women described their maximum labor pain as “unbearably painful,” and more than one-half reported that they were “very frightened” or “terrified.” The deliveries of Bedouin mothers were remarkable for the absence of pain behaviors; yet their VAS reports indicated that they experienced no less pain. Painful menstruation and fear of childbirth emerged as risk factors for a painful labor. Among the issues discussed are the validity of the VAS data, the difficulties of managing Bedouin mothers' pain, and the importance of excluding physical factors before cultural differences in pain perception are assumed. 相似文献
30.
目的:研究金欣口服液含药血清对呼吸道合胞病毒(RSV)黏附、膜融合的影响。方法:在病毒和细胞接触期间采用转换温度方法观察金欣口服液含药血清对RSV黏附、侵入的影响。结果:温度转换前(黏附阶段)加入金欣口服液含药血清,实验组和对照组OD值无差异;温度转换后(侵入阶段)加入金欣口服液含药血清组OD值明显升高,与对照组比有显著性差异。结论:金欣口服液含药血清的抗病毒作用在呼吸道合胞病毒黏附后的膜融合及侵入阶段。 相似文献