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61.
Previous surveys have indicated that there is a substantial proportion of dentally anxious individuals in the general population. Many of these individuals avoid contact with dentistry as much as possible, while fearful individuals who present themselves for treatment are probably too uncomfortable or too afraid to make their views known. Consequently, a study of the feelings and attitudes of a group of dental phobics was carried out as part of a larger study of the efficacy of psychological treatments for excessive dental anxiety. The subjects were recruited by means of a newspaper advertisement and asked to complete a questionnaire designed to obtain information regarding their dental experiences and attitudes. Twenty-three individuals provided enough data for analysis. They were distributed widely in terms of age, education, income levels, and general fearfulness. They reported less satisfaction with the level of understanding or acceptance found in the last dentist they had seen than with the dentist's level of technical competence and the diagnostic information they received. Dental phobics who had been to a dentist in the past year were generally more satisfied with their dentist than those who had not. It is suggested that a good dentist-patient relationship based on understanding and acceptance is an important factor in overcoming the avoidance of fearful patients. 相似文献
62.
cDNA probes for human retinoic acid receptors α and β (RARα and RARβ) were modified for use as specific hybridization probes to study hepatocellular carcinomas (HCC) and cell lines, liver regeneration, and fetal development. RARβ mRNA was detected at low levels in adult liver and rose markedly during the early phase of liver regeneration. RARβ mRNA was present at very low levels in HCC and was not detected in fetal liver. In contrast, RARα mRNA was present at low levels in normal liver, but showed a marked elevation in several HCCs and cell lines. Growth of cell lines was altered by retinoic acid (RA), but the effects could not be predicted by the levels of either RARα or RARβ mRNA. However, the response correlated with cell phenotype. Three cell lines with an adult phenotype (high albumin and low α-fetoprotein) were inhibited by RA, two undifferentiated lines showed moderate growth stimulation, and two of three cell lines that had high levels of α-fetoprotein were markedly stimulated by RA. 相似文献
63.
Gary D. Slade David Locker James L. Leake Sherry A. Price Irene Chao 《Community dentistry and oral epidemiology》1990,18(5):272-286
Differences in oral health status between independent and institutionalized adults have been difficult to interpret because the latter population is typically older and has a higher proportion of women, confounding any association between institutionalization and disease levels. We undertook an analysis of oral disease amongst institutionalized (n = 149) and non-institutionalized (n = 246) samples of older adults randomly selected from the population in East York, Ontario. When the confounding effects of age and gender were controlled by constructing 67 matched pairs, institutionalized people were more than twice as likely to be edentulous (OR = 2.17, 95% CI = 1.09-4.29). This association was confirmed using data from all subjects in a logistic regression model. Analysis of covariance of data from dentate subjects revealed that the institutionalized seniors had fewer filled teeth (P less than 0.05, controlling for age and sex), but there were no statistically significant differences in the number of teeth which were missing, decayed, or requiring extraction. These findings suggest that antecedent, sociodemographic factors prior to institutionalization are responsible for the higher probability of oral disease in this group of older adults. 相似文献
64.
Transient synovitis of the hip in children: role of US 总被引:7,自引:0,他引:7
Marchal GJ; Van Holsbeeck MT; Raes M; Favril AA; Verbeken EE; Casteels- Vandaele M; Baert AL; Lauweryns JM 《Radiology》1987,162(3):825-828
Transient synovitis of the hip remains a common diagnostic problem for the clinician. The physical signs are not pathognomonic of the condition, and the classic technical examinations are of little help. Therefore, the authors retrospectively studied the value of hip arthrosonography in 46 children with clinical symptoms suggesting pathologic hip conditions. In 20 of the 21 patients with a final diagnosis of transient synovitis, articular effusion was detected on ultrasound (US). Conventional radiography showed an increased medial joint space in only eight of these patients. Increased echogenicity of the articular fluid was found in both transient synovitis and septic arthritis. The high sensitivity of US in detecting intraarticular fluid was demonstrated by cadaver studies. 相似文献
65.
A comparative analysis of nuclear DNA content and N-myc gene amplification in neuroblastoma 总被引:2,自引:0,他引:2
Nuclear DNA content and N-myc amplification have been found to have prognostic significance in neuroblastoma. To investigate the interrelationships between these two parameters, tumor samples from 18 patients with neuroblastoma were analyzed for both total DNA and N-myc gene content. Quantitative DNA analysis was performed by image analysis. Quantitative Southern blot hybridization was used to determine N-myc gene copy number and to distinguish between low level gene amplification or excess gene copies secondary to aneuploidy. Six of the 18 patients have died. Five of the six had nonaneuploid tumors, but only two of the six exhibited major N-myc amplification. Low-level amplification was detected in one Stage II patient. The authors' results suggest that neuroblastomas with N-myc amplification are a subset of nonaneuploid tumors. 相似文献
66.
Arthroscopy is an indispensable tool in the diagnosis, treatment, and postoperative follow-up of pigmented villonodular synovitis (PVNS) and enables classification of PVNS into three forms: diffuse, localized, and mixed. A series of 13 cases of PVNS of the knee is presented; 12 patients underwent surgery. According to the anatomic type of PVNS found, the authors used extensive classic surgery or endoscopy. Follow-up averaged 4.2 years (range, 1-10 years). The best results were obtained in cases of localized PVNS. Overall, nine patients were totally asymptomatic at follow-up. Four patients experienced some pain when fatigued or with changes in the weather. There was no recurrence of symptoms. 相似文献
67.
GJ Levy ; G Selset ; D McQuiston ; SJ Nance ; G Garratty ; LE Smith ; D Goldfinger 《Transfusion》1988,28(3):265-267
Several published reports have documented the variable survival of Yt(a+) red cells (RBC) in patients with anti-Yt(a) as measured by 51Chromium (Cr)-labeled RBC survival studies. Similar studies with anti-Yt(b) have not been reported. A 51Cr-labeled RBC survival study was performed using Yt(b+) RBCs and a monocyte monolayer assay in a young hemodialysis patient who required chronic transfusion therapy and who had developed anti-Yt(b). The survival of the transfused RBCs was 100 and 93 percent at 1 and 24 hours, respectively, with a half life of 21 days at termination of the study (normal, 28 to 32 days). These results showed no evidence of rapid destruction of the Yt(b+) RBCs, indicating that this patient could be transfused safely with blood from Yt(b+) donors. Long-term survival of the 51Cr-labeled Yt(b+) RBCs was shortened moderately, however, a finding that correlated with a slightly abnormal monocyte monolayer assay test. 相似文献
68.
Objectives: To describe changes in the case mix, demographics, waiting times (WTs; time from arrival in the emergency department (ED) until seen by a clinician) and treatment times (TTs; time from seeing a clinician until leaving the ED) of adult patients presenting to the EDs in Sheffield, UK, between 1993 and 2003. Design: A retrospective analysis of routinely collected data. Results: Of a total of 252 156 patients included in the study, the proportion of attendees aged 16–29 years decreased from 38.7% in 1993 to 28.8% in 2003 (rate of change (b) = –1.10% per year, 95% CI –1.20% to –0.82%, p<0.001) whereas the proportion aged 80–99 years increased from 6.2% to 10.4% (b = 0.37% per year, 95% CI 0.29% to 0.45%, p<0.001). The proportion of "minors" (patients not arriving by ambulance and subsequently discharged) fell from 71.1% in 1993 to 60.8% in 2003 (b = –1.04% per year, 95% CI –1.36% to –0.73%, p<0.001). WTs increased from a median of 21 minutes in 1993 to 48 minutes in 2003 (b = 3.5 min per year, 95% CI 2.23 min to 4.77 min, p<0.001). The median TT for minors was unchanged but that for majors (patients arriving by ambulance and admitted to hospital from the ED) increased from 55 to 205 minutes (b = 11.55 min per year, 95% CI 6.54 min to 16.55 mins, p = 0.01). Conclusion: The demographics, case mix, and waiting times of patients presenting to EDs in Sheffield changed considerably over an 11 year period. There is evidence that the service for minor case patients improved slightly at the end of the period studied, but this is possibly at the expense of a deteriorating experience for major case patients. 相似文献
69.
目的:探索膝关节前交叉韧带重建术的各个关键技术环节,为提高前交叉韧带修复的临床效果提供理论和实践依据。方法:通过分析与总结与前交叉韧带重建相关的文献资料,包括其手术方式、移植物的选择、骨道定位、髁间窝成形、移植物预张与张力、移植物固定等,同时结合作者的工作经验旨在进一步提高前交叉韧带重建技术。结果:①手术方式选择:膝关节镜下生物材料移植重建前交叉韧带取得比以往优良的临床效果,已得到广泛认可。多数采用单束重建,部分学者正在尝试双束重建以改善移植物生物力学性能。②移植材料的选择:包括自体和同种异体材料,其中自体骨-髌腱-骨与腘绳肌腱最为常用。骨-髌腱-骨由于两端带有骨块,固定牢靠,允许早期重返运动场,颇受年轻运动员青睐。腘绳肌腱取材切口小,术后很少出现膝前痛,但其稳定性不如骨-髌腱-骨,且术后相对容易出现骨隧道扩大。异体移植物在体内结合、重塑速度较自体移植慢,但若经过严格的供体筛选、合理的组织取材、消毒和保存,而不减弱移植物强度,仍可取得与自体移植相当的效果。③骨道位置:正确的骨道定位非常重要,骨道位置太靠前会造成髁间窝撞击和伸直受限。研究表明,术中采用骨性标志定位法要比采用软组织标志定位法准确,术中摄片有助于骨道位置的正确定位。④髁间窝成形术:髁间窝成形的目的是为了便于更清楚的观察髁间窝后侧,同时也是为了避免髁间窝撞击综合征的发生,由于髁间窝过度成形会增加关节出血、疼痛、肿胀以及骨赘生长,所以一般不主张广泛的髁间窝成形,除非术中确有必要时才进行。⑤移植物预张与张力:移植物初始张力不够会导致膝关节持续松弛,而张力过高会限制关节活动并加速关节退变。目前对于最佳的初始张力尚无确切说法。⑥固定:现在已经研制出许多不同类型的固定材料。对于骨-髌腱-骨而言,界面挤压螺钉单切口重建前交叉韧带时,股骨侧靠近关节腔侧固定,胫骨侧远离关节腔侧固定,双切口技术时胫骨侧靠近关节腔侧固定,股骨侧远离关节腔侧固定。股骨侧固定完毕后,膝关节取何角度对胫骨侧进行固定尚存争议。膝关节稍屈曲状态下固定不容易发生松弛,但正常的膝关节在前后方向上是允许有一定松弛度的。有些学者认为在膝关节完全伸直状态下固定可以避免屈曲挛缩畸形的发生并允许前后方向有轻度松弛。而有些学者认为在膝关节稍微屈曲状态下固定会更紧。结论:要真正做到解剖、生物力学、生理功能全方位重建,前交叉韧带重建技术,仍需不断完善,分子生物学、基因工程和组织工程技术的发展以及计算机辅助机器人手术的开展会使前交叉韧带重建技术日臻完善。 相似文献
70.
目的:建立血虚和免疫抑制动物模型,观察鸡胚胎低温提取物对其红细胞造血以及免疫器官质量的影响。方法:实验于2001-04/2002-09在新乡医学院药物研究室完成。①实验材料:健康昆明种小鼠50只,雌雄各半。鸡胚胎素[中国发明专利公开(公告)号:CN1748713],符合研究者申报专利时提出的质量检验标准。②鸡胚胎素对血虚模型小鼠红细胞数值及血红蛋白含量的影响:取20只小鼠,随机排列表法分为鸡胚胎素组、模型对照组,10只/组,建立失血性血虚动物模型。失血后24h当红细胞数<3.2×1012L-1、血红蛋白含量<84g/L,且小鼠外观出现皮色苍白、食欲不振等现象时,代表造模成功。次日,鸡胚胎素组给予鸡胚胎素5g/(kg·d)灌胃,模型对照组给予生理盐水20mL/(kg·d)灌胃,连续14d。分别于失血前、失血后24h、末次给鸡胚胎素后2h尾部采血测定两组红细胞数量及血红蛋白含量的变化。③鸡胚胎素对免疫抑制模型小鼠免疫器官质量的影响:取30只小鼠,随机排列表法分为鸡胚胎素组、模型对照组、正常对照组,10只/组。鸡胚胎素组给予鸡胚胎素5g/(kg·d)灌胃,模型对照组和正常对照组均灌服等量生理盐水,连续14d。在第11天上午鸡胚胎素灌胃2h后,鸡胚胎素组、模型对照组腹腔注射环磷酰胺60mg/(kg·d),连续4d,复制免疫抑制动物模型。末次给予环磷酰胺2h后颈椎脱位法处死小鼠,计算胸腺、脾脏质量指数。结果:50只小鼠均进入结果分析。①失血前及失血后24h鸡胚胎素组与模型对照组的红细胞数值、血红蛋白含量基本相似(P>0.05)。末次给鸡胚胎素后2h与模型对照组比较,鸡胚胎素组红细胞数值、血红蛋白含量均明显升高(t=3.39,P<0.01;t=2.52,P<0.05)。②末次给环磷酰胺2h后与模型对照组比较,鸡胚胎素组、正常对照组的胸腺质量指数和脾脏质量指数均明显升高(t=6.62,P<0.01;t=2.47,P<0.05)。结论:鸡胚胎素灌胃对血虚小鼠具有较好的促红细胞造血功能,同时对环磷酰胺造成的免疫器官质量下降具有明显的增重作用。 相似文献