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81.
陆奔 《医学美学美容》2023,32(22):142-145
评估上颌唇侧倒置埋伏中切牙患者正畸矫治后埋伏牙发生及牙根吸收的影响因素。方法收集2019年3月-2021年3月于溧阳市人民医院就诊的1021例上颌唇侧倒置埋伏中切牙患者临床资料进行回顾性调查,查阅锥形束CT及X线图像。其中113例发现埋伏牙,按照是否出现牙根吸收分为牙根吸收组(51例)和牙根未吸收组(62例)。调取资料,包括性别、初诊年龄、平均体质量指数、埋伏牙位置、近远中分区、是否拔牙、正畸治疗时间、埋伏牙发生个数等。统计上述指标情况,分析正畸矫治后埋伏牙牙根吸收的单因素和多因素。结果 1021例患者中埋伏牙113例(11.07%);牙根吸收组平均年龄、2~4区占比均低于牙根未吸收组(P <0.05);牙根吸收组拔牙率、正畸治疗时间>2年占比均高于牙根未吸收组(P <0.05);两组性别、平均体质量指数、埋伏牙位置、病变位置、埋伏牙发生个数比较,差异无统计学意义(P >0.05);Logistic结果显示,高龄、近远中分区(0~1区)、拔牙、正畸治疗时间>2年均为正畸矫治后埋伏牙牙根吸收的高危因素(P <0.05)。结论 上颌唇侧倒置埋伏中切牙正畸矫治后埋伏牙牙根吸收与年龄、近远中分区、拔牙、正畸治疗时间有关,对于高危因素患者,临床应给予重视,采用早期干预措施,减少损伤。  相似文献   
82.
Background: Dental injury is well recognized as a potential complication of laryngoscopy and tracheal intubation. The flange of the Macintosh blade may contact teeth during laryngoscopy causing damage. The Callander modification of the Macintosh blade (Callander blade) with a shortened heel at the proximal end has been shown to increase the blade–tooth distance and reduce contact rates in adults. Aim: This study was designed to evaluate the effectiveness of the Callander blade on reducing dental contact in children. Methods: One hundred children, aged 4–14 years, scheduled for general anesthesia requiring endotracheal intubation were studied prospectively. The children were preoperatively evaluated for Mallampati score and dental defects, looseness, and avulsions. Following induction of anesthesia, laryngoscopy was performed twice on each child in succession, once with a standard Macintosh blade and once with a Callander blade of the same size in a random order. The blade–tooth distance and contact rate were compared between the two blades. Results: With the Callander blade, the blade–tooth distance was greater than with the Macintosh (1.78 ± 1.77 vs 0.28 ± 0.76 mm, P = 0.001). The frequency of direct contact was less with the Callander blade than it was with the Macintosh blade (33% vs 86%, respectively, P = 0.008). However, difficult laryngoscopy rate did not differ between the blades. Tracheal intubation was successful in all children and there was no dental injury. Conclusion: Our findings suggest that the Callander blade decreases the risk for dental injury and provides tracheal intubating conditions in children with normal airways similar to those obtained with a traditional Macintosh blade.  相似文献   
83.
Germ cell tumours are highly curable, especially when still at the localized stage, which is the case for most testicular tumours. Various options are available for organ-confined disease; depending on the histological review, patients with clinical stage I seminomas can be offered radiotherapy, surveillance or chemotherapy, whereas those with clinical stage I nonseminomas can be offered retroperitoneal lymph node dissection, surveillance or chemotherapy. As it is unlikely that any of these approaches will have a clear survival advantage, the most appropriate variables to be considered are acute and late side-effects, acceptability and quality of life. In recent years adjuvant chemotherapy has been extensively evaluated in patients with seminoma or nonseminoma. In this review we discuss the advantages and disadvantages of the different strategies for treating seminomas and nonseminomas, and their associated prognostic factors, and then consider future developments.  相似文献   
84.

Objectives:

The aim of the present study was to analyse the mineralization pattern of enamel and dentin in patients affected by X-linked hypophosphatemic rickets (XLHR) using micro-CT (µCT), and to associate enamel and dentin mineralization in primary and permanent teeth with tooth position, gender and the presence/absence of this disease.

Methods:

19 teeth were collected from 5 individuals from the same family, 1 non-affected by XLHR and 4 affected by XLHR. Gender, age, tooth position (anterior/posterior) and tooth type (deciduous/permanent) were recorded for each patient. Following collection, teeth were placed in 0.1% thymol solution until µCT scan. Projection images were reconstructed and analysed. A plot profile describing the greyscale distance relationship in µCT images was achieved through a line bisecting each tooth in a region with the presence of enamel and dentin. The enamel and dentin mineralization densities were measured and compared. Univariate ANOVA and post hoc Tukey tests were used for all comparisons.

Results:

Teeth of all affected patients presented dentin with a different mineralization pattern compared with the teeth of healthy patients with dentin defects observed next to the pulp chambers. Highly significant differences were found for gray values between anterior and posterior teeth (p < 0.05), affected and non-affected (p < 0.05), as well as when position and disease status were considered (p < 0.05).

Conclusions:

In conclusion, the mineralization patterns of dentin differed when comparing teeth from patients with and without FHR, mainly next to pulp chambers where areas with porosity and consequently lower mineral density and dentin defects were found.  相似文献   
85.
AIM: To evaluate the feasibility and usefulness of high dose chemotherapy including paclitaxel (T-ICE) combined with peripheral blood stem cell transplantation (PBSCT) for male germ cell tumor. METHODS: Five male patients with advanced germ cell tumor underwent 1-6 courses of high dose chemotherapy including paclitaxel (T-ICE; 175 mg/m2 of paclitaxel, 1250 mg/m2 of carboplatin, 1500 mg/m2 of etoposide and 7.5 g/m2 of ifosfamide) with PBSCT after 2-3 courses of induction chemotherapy (PEB or VIP). RESULTS: In all patients, serum marker levels decreased to within the normal range by T-ICE. Two patients underwent resection of residual tumor. In one patient, viable cancer cells were detected in resected lymph node tissue and adjuvant chemotherapy was then performed. Although the follow-up period was short (7-15.5 months), four of the five patients (80%) showed no evidence of recurrent disease. No significant differences in side-effects were noted between T-ICE and conventional high dose ICE, which was previously performed in 39 patients at the Division of Urology, Kobe University Graduate School of Medicine, Japan. CONCLUSIONS: High dose chemotherapy, including T-ICE, combined with PBSCT showed an almost identical degree of side-effects as seen in previous high dose chemotherapy without paclitaxel. Although 80% of the patients showed no evidence of disease so far, the efficacy of T-ICE should be evaluated with more patients and longer follow up.  相似文献   
86.
目的探讨上颌前牙美观区单牙即刻非功能性负重人工牙种植的临床效果。方法对26例26颗上颌前牙种植者,在置入种植体的同时,接入临时基台行复合树脂暂时冠临时修复,2~6个月后,更换永久性烤瓷冠修复体。结果种植体置入后,随访12-72个月,没有种植体丢失。前12个月平均边缘骨丧失为0.78mm,随访期内,累积平均骨丧失为1.17mm。结论严格掌握适应证,上颌前牙单牙即刻非功能负重种植,能满足患者临时的美观需求,临床效果良好。  相似文献   
87.
实验性睾丸缺血超声表现与再灌注后组织变化相关性研究   总被引:1,自引:1,他引:1  
目的:探讨不同程度急性单侧睾丸缺血的二维、彩色多普勒(CDU)及超声造影表现与再灌注后睾丸病理变化的相关性。方法:32只大白兔随机分成对照组、缺血组(A、B、C组),每组8只。缺血组在超声监测下制成不同程度的单侧睾丸缺血模型,A组,睾丸回声均匀、血流信号轻度减少;B组,睾丸回声不均匀、血流信号明显减少;C组,睾丸出现放射状或小片状低回声、血流信号消失。各组在出现上述声像图变化后予以再灌注。缺血前及再灌注前分别行双侧睾丸超声造影。1个月后观察各组缺血睾丸病理变化。比对分析各组超声表现与生精功能之间的关系。结果:超声造影:与对照组比较,A、B组缺血睾丸造影参数到达时间、速度、达峰时间、峰值减半时间有显著差异(P<0.05),峰值基础强度差A组无明显差异(P>0.05)、B组有显著差异(P<0.05);C组无造影剂充盈。1个月后缺血睾丸Johnsen评分:与对照组(9.10±0.11)比较,A组(8.70±0.39)无显著差异(P>0.05),B组(6.01±0.88)有显著差异(P<0.05),C组(3.16±1.05)有极显著差异(P<0.01)。结论:与CDU相比,超声造影能较好地反映缺血睾丸组织的血流灌注情况,睾丸缺血的不同超声表现与再灌注后生精功能明显相关,超声检查能对再灌注后睾丸生精功能的预测提供帮助。  相似文献   
88.
Objective:   To report our experience with post-chemotherapy nerve-sparing retroperitoneal lymph node dissection (RPLND) for advanced germ cell tumor (GCT).
Methods:   Between 1994 and 2008, 92 patients with advanced GCT underwent RPLND after multiple treatments with systemic chemotherapy at our institution. A nerve-sparing RPLND was carried out in 78 patients (84.8%; median age 32 years). Of them, 19 had a seminoma and 59 had a non-seminoma.
Results:   Lumbar splanchnic nerves controlling ejaculatory function were macroscopically preserved during RPLND. Bilateral and unilateral lumbar splanchnic nerves were preserved in 40 patients and 38 patients, respectively. Sixty-five patients could be evaluated for ejaculation. Fifty-four patients (83.1%) achieved antegrade ejaculation with a median postoperative interval of 3 months (range: 1–10 months). Twenty-eight patients (28/30: 93.3%) and 26 patients (26/35: 74.3%) undergoing bilateral and unilateral nerve-sparing RPLND had antegrade ejaculation, respectively ( P  = 0.041). Only two patients (2.6%) had mediastinal and retroperitoneal recurrences during a median follow-up of 42 months (range: 1–138 months), respectively. However, these patients were cured by chemotherapy and surgery.
Conclusions:   Post-chemotherapy nerve-sparing RPLND preserves ejaculatory function in the majority of patients with advanced GCT without increasing the risk of local recurrence.  相似文献   
89.
Cubilin (cubn) is a receptor for vitamins and various protein ligands. Cubn lacks a transmembrane domain but anchors to apical membranes by forming complexes with Amnionless or Megalin. In an effort to better understand the uptake of nutrients in testis, we analysed cubn expression in the developing mice testes. In testes, cubn mRNA increased from birth to adulthood. In the inter‐stitium and isolated seminiferous tubules, neonatal increase in cubn mRNA until 14 days post‐partum (pp) was followed by a marked increase at puberty (28 days pp). Cubn was found in the gonocytes, spermatogonia, spermatocytes and spermatids in the developing testes. In adult testes, strong Cubn immunoreactivity was found in the elongating spermatids, suggesting the role of Cubn in endocytosis during early spermiogenesis. In Sertoli cells and peritubular cells, Cubn immunoreactivity was weak throughout the testis development. In the inter‐stitium, Cubn immunoreactivity was found in foetal Leydig cells, was weak to negligible in the stem cells and progenitor Leydig cells and was strong in immature and adult Leydig cells, demonstrating a positive association between Cubn and steroidogenic activity of Leydig cells. Collectively, these results suggest that Cubn may participate in the endocytotic uptake of nutrients in germ cells and somatic cells, supporting the spermatogenesis and steroidogenesis in mouse testes.  相似文献   
90.
目的:探讨腹腔镜改良性腹膜后淋巴清除术初步经验,评估其手术可行性和近期临床疗效。方法:2004年10月~2006年7月,对7例临床诊断为Ⅰ期睾丸非精原细胞瘤患者,施行了经腹腔途径腹腔镜改良性腹膜后淋巴清除术,年龄26~36岁,平均年龄为30岁,睾丸肿瘤大小为3.0 cm×2.5 cm×2.0 cm~6.5 cm×4.5 cm×3.0 cm,左侧3例,右侧4例,均通过B超、腹膜后CT、胸片检查,并施行了根治性睾丸切除和病理证实。术后淋巴结阳性患者施行了3个疗程的化疗。结果:7例均获得成功,无1例改开放手术。手术时间为120~210 min,平均160 min,手术失血量50~200 ml,平均150 ml,均未输血。术后1~3 d肛门排气,于1~2 d拔除引流管;术后平均住院时间5.5 d。病理报告6例均无转移性淋巴结,其中1例为1/18淋巴结转移,术后无明显并发症。随访6~32个月,平均14个月,阴茎勃起功能良好,射精功能正常。定期复查血hCG、AFP均阴性,B超复查均未发现腹膜后淋巴结,胸片表现均正常。其中淋巴结阳性1例患者术后接受3个疗程的辅助化疗,随访6个月,无瘤存活。结论:腹腔镜改良性腹膜后淋巴清除术具有损伤小、并发症少、术后恢复快等特点,可以代替传统开放手术。  相似文献   
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