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11.
As the biological width is established around neighboring implants, there is a flattening of the interimplant bone and a change in the position of the soft tissue. As a result, a normal progression of papilla from natural teeth through the adjacent implant area is lost. This presentation describes various techniques and strategies to improve the aesthetic outcome of anterior implant restorations, together with the use of a scalloped implant designed to sustain the interdental bony peaks, and in doing so, maintain the interimplant papillae. 相似文献
12.
K Andersson 《Acta physiologica Scandinavica》1989,135(4):449-457
The effects of SCH 23390 (D1 dopamine receptor antagonist), SK&F 38393 (D1 dopamine receptor agonist), raclopride and remoxipride (D2 dopamine receptor antagonists) and ketanserin (5-hydroxytryptamine 2 receptor antagonist) on TSH serum levels (radioimmunoassay) and on brain catecholamine levels (Falck-Hillarp methodology in combination with quantitative histofluorimetry) were studied. SCH 23390 produced a dose-dependent increase in serum TSH levels in the lower dose range (0.01-0.03 mg kg-1, i.p.) administered 30 min before decapitation and in the higher dose range (1.0-3.0 mg kg-1) when given 2 h before decapitation. Following 30 min of treatment with the high doses of SCH 23390, reductions in serum TSH levels were found. The changes observed following SCH 23390 treatment occurred without affecting catecholamine levels in the median eminence and the peri- and paraventricular hypothalamic regions. Raclopride (0.1-10 mg kg-1, i.p.), remoxipride (1.0 mg kg-1, i.p.) or ketanserin (0.3 mg kg-1, i.p.) changed neither serum TSH levels nor brain catecholamine levels, SK&F 38393 (1.0-10 mg kg-1, i.p.) produced an increase in serum TSH levels. The results suggest the existence of inhibitory and facilitatory mechanisms regulating TSH secretion mediated via D1 dopamine receptors. 相似文献
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Antonio Gómez Mercedes Salgado Manuel Valladares-Ayerbes Mónica Jorge Ana Carballo Sonia Candamio Pilar Izquierdo Paula Peleteiro Rafael López 《Clinical & translational oncology》2010,12(12):843-848
Objective
The aim of the project was to assess the effectiveness and safety of weekly epoetin-beta (EB) in patients with gastrointestinal cancer (GIC) subjected to concomitant chemoradiotherapy (CCTRT). 相似文献15.
16.
Mozammil Hussain Raghu N. Natarajan Amir H. Fayyazi Brian R. Braaksma Gunnar B.J. Andersson Howard S. An 《The spine journal》2009,9(12):1016-1023
Background contextAnterior corpectomy and reconstruction with bone graft and a rigid screw-plate construct is an established procedure for treatment of cervical neural compression. Despite its reliability in relieving symptoms, there is a high rate of construct failure, especially in multilevel cases.PurposeThere has been no study evaluating the biomechanical effects of screw angulation on construct stability; this study investigates the C4–C7 construct stability and load-sharing properties among varying screw angulations in a rigid plate-screw construct.Study designA finite element model of a two-level cervical corpectomy with static anterior cervical plate.MethodsA three-dimensional finite element (FE) model of an intact C3–T1 segment was developed and validated. From this intact model, a fusion model (two-level [C5, C6] anterior corpectomy) was developed and validated. After corpectomy, allograft interbody fusion with a rigid anterior screw-plate construct was created from C4 to C7. Five additional FE models were developed from the fusion model corresponding to five different combinations of screw angulations within the vertebral bodies (C4, C7): (0°, 0°), (5°, 5°), (10°, 10°), (15°, 15°), and (15°, 0°). The fifth fusion model was termed as a hybrid fusion model.ResultsThe stability of a two-level corpectomy reconstruction is not dependent on the position of the screws. Despite the locked screw-plate interface, some degree of load sharing is transmitted to the graft. The load seen by the graft and the shear stress at the bone-screw junction is dependent on the angle of the screws with respect to the end plate. Higher stresses are seen at more divergent angles, particularly at the lower level of the construct.ConclusionThis study suggests that screw divergence from the end plates not only increases load transmission to the graft but also predisposes the screws to higher shear forces after corpectomy reconstruction. In particular, the inferior screw demonstrated larger stress than the upper-level screws. In the proposed hybrid fusion model, lower stresses on the bone graft, end plates, and bone-screw interface were recorded, inferring lower construct failure (end-plate fractures and screw pullout) potential at the inferior construct end. 相似文献
17.
Jenny Andersson Barbro Linderholm Jonas Bergh Goran Elmberger 《Applied immunohistochemistry & molecular morphology》2004,12(1):14-20
We have studied the intratumor HER-2/neu heterogeneity in 78 consecutive and population-based primary invasive breast carcinomas. Within the invasive component, heterogeneity was detected in only 1 of 78 tumors. In 48 tumors (62%), we found both in situ and invasive components in analyzed tissue sections. Twelve of these 48 tumors had a difference of at least 2 arbitrary units in the in situ compared with the invasive part of the tumor with regard to the HER-2/neu status analyzed by HercepTest (immunohistochemistry). Eight of these 12 tumors were reanalyzed with fluorescent in situ hybridization and immunohistochemistry with and without a new Automated Cellular Imaging System. In this limited material, immunohistochemistry in combination with the Automated Cellular Imaging System seemed to have a better correlation with fluorescent in situ hybridization than immunostaining analyzed manually. In conclusion, HER-2/neu expression is not seldom heterogeneous in invasive compared with in situ components within a tumor. This finding should be considered in the choice of evaluation method. To avoid heterogeneity as a confounding factor in HER-2/neu analyses, detection methods such as immunohistochemistry and fluorescent in situ hybridization, which can provide evaluation in a preserved tissue architecture, should be used. Perhaps the intratumor HER-2/neu heterogeneity can explain some of the unexpected failures of trastuzumab therapy. 相似文献
18.
Jennifer P. Friedberg Marios N. Adonis Heather A. Von Bergen Sonia Suchday 《Stress and health》2005,21(1):53-60
Exposure to trauma and stress has been linked with poor health, while forgiveness appears to be positively associated with health outcomes. The current study investigates whether traits such as forgiveness and ruminative tendencies predict levels of trauma and stress experienced by New York City residents on the 1‐year anniversary of the September 11th terrorist attack. Seventy‐one students and staff members (57 females, 14 males) of a graduate school in New York City were administered the Impact of Events Scale, the Perceived Stress Scale, and questionnaires designed for the purpose of this study to measure ruminative tendencies and forgiveness on September 11, 2002. Rumination predicted levels of trauma (p < 0.05) and perceived stress (p < 0.01). Lower levels of forgiveness predicted perceived stress (p < 0.05), but not trauma. Rumination mediated the relationship between forgiveness and perceived stress. These findings suggest that individuals with higher levels of rumination have an elevated risk of experiencing trauma and stress‐related symptoms following a traumatic event. Forgiveness is associated with lower levels of stress, but not trauma, perhaps because trauma is an extreme form of stress. Forgiveness appears to serve as a buffer against stress more so in individuals with low levels of rumination than in individuals with high levels of rumination. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
19.
Abstract Caries experience and enamel fluorosis prevalence in 8-year-old children belonging to different socio-economic classes were determined in two Chilean twin cities that are served by optimally fluoridated community water from the same waterworks facility. Low socio-economic status (LSES) children had a higher mean dm ft and DMFT indices (P<0.001) than high socioeconomic status (HSES) children. Prevalence of enamel fluorosis in the permanent teeth of LSES children was 0.79, significantly higher (X2= 9.0; P<0.003) than the value 0.59 found in HSES children. The proportion of Dean's scores 2. 3, 4 and 5 in first molars, mandibular and maxillary incisors in LSES children was higher than in HSES children (P<0.001). Differences in prevalence and seventy of enamel fluorosis between both groups are tentatively attributed lo a different pattern of tap water and tea consumption at pre-school ages. Suggestions are advanced to minimize the undesirable prevalence and severity of enamel fluorosis. 相似文献
20.