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11.
目的X-Rite’sShadeVision System和Vitapan Classical比色板的匹配性。方法采用X-Rite’sShadeVision System对Vitapan Classical比色板进行测色。结果X-Rite’s ShadeVision System测量结果排序与原排序一致,排列差异最大有6个色片的差距。相邻比色板的色差ΔEab参差不齐,最大的色差6.92,而最小的色差只有1.21。结论X-Rite’s ShadeVision System与Vitapan Classical比色板不完全匹配。  相似文献   
12.
根管预备并发症及充填质量的临床评价   总被引:10,自引:1,他引:10  
目的:对根管预备并发症及充填质量进行临床评价。方法:从Digora图像系统中抽取我科2002—04—05所完成的根管治疗病例805例,分别对前牙、前磨牙和磨牙根管预备并发症的发生和充填质量进行分析。结果:形成台阶和侧穿的比例在前磨牙分别为4%,而在磨牙中则分别为33%和5%。前牙、前磨牙和磨牙适充的比例分别为74%、69%和50%。结论:磨牙根管预备和充填的质量仍有待进一步提高。  相似文献   
13.
目的 利用蛋白质组技术探讨牙髓对中龋和热刺激的反应.方法 用双向电泳得到牙髓在中龋和热刺激状态下的二维电泳图谱,对差异点进行质谱鉴定.结果 经Image Master2-D Platinum 5.0软件分析显示,正常牙髓和中龋牙髓的蛋白表达无显著差异;热损伤牙髓有2个蛋白点缺失,8个蛋白点下调.质谱分析鉴定了7种蛋白质.结论 本实验条件下,中龋牙髓的蛋白质表达与正常牙髓无显著差异,热刺激可造成部分蛋白表达的下调.  相似文献   
14.
2447例唇腭裂患者的临床资料分析   总被引:13,自引:0,他引:13  
目的 了解先天性唇腭裂的患病状况及特点 ,寻找与唇腭裂发生有关的影响因素 ,为唇腭裂的预防与治疗提供依据。方法 对 1989~ 1998,10年间在原华西医科大学口腔医院颌面外科手术治疗的 2 4 4 7病例进行回顾性临床统计学分析。结果 在本组病例中 ,唇裂 6 4 8(2 6 5 % )、唇腭裂 996 (40 7% )、单纯腭裂 80 3(32 8% )。唇裂伴或不伴腭裂中 ,男多于女 (2 .14∶1) ,单纯腭裂女多于男 (0 77∶1)。单侧唇腭裂明显多于双侧 ,两者之比为 4 84∶1,其中左侧者多于右侧者 ,两者之比为 2 14∶1。有遗传史的病例占病例总数的 7 4 % ,其中唇裂伴或不伴腭裂有遗传史者占唇裂伴或不伴腭裂患者的 8 2 % ,单纯腭裂有遗传史者占单纯腭裂患者的 6 5 %。母亲怀孕前 3月经历危险因素有 95 4例 ,占 39 0 % ,其中唇裂伴或不伴腭裂者 70 0例 ,占唇裂伴或不伴腭裂患者数的 4 2 6 % ,单纯腭裂2 5 4例 ,占单纯腭裂的 31 6 %。A型和O型血患者比例高于正常人群比例 ,而B型血者比例低于正常人群比例 ,单纯唇裂出生于 4~ 6月者人数小于其他季度 ,而单纯腭裂出生于 7~ 9月者人数少于其他季度 ;19例双生子中 ,均为其中之一发病 ,无同时发病者。唇腭裂伴发畸形者共 4 1例 ,占总病例数的 1 7%。结论 本资料提示唇腭裂的发生可?  相似文献   
15.
Problem-based learning (PBL) is a widely accepted educational method centered on the discussion and learning that emerge from a clinically based problem; however, little has been reported on the details of PBL case-writing in the dental education literature. This article outlines some principles of writing a PBL case as it is practiced at a Chinese dental school and presents, as an example, an actual case based on a clinical problem (ameloblastoma of the jaw) intended to provide a learning focus for predoctoral dental students. A good PBL case should allow for progressive, interdependent actions to be taken in the evaluation and overall management of the patient in context and should trigger inquiry and discussion among students in both the basic sciences (anatomy, physiology, biochemistry, pharmacology, pathophysiology, etc.) and related clinical sciences. The epidemiological, sociological, and ethical considerations related to each problem should also be emphasized as an essential component of effective health care provision.  相似文献   
16.
Objective The relationship between serum uric acid(SUA)levels and glycemic indices,including plasma glucose(FPG),2-hour postload glucose(2 h-PG),and glycated hemoglobin(HbA1 c),remains inconclusive.We aimed to explore the associations between glycemic indices and SUA levels in the general Chinese population.Methods The current study was a cross-sectional analysis using the first follow-up survey data from The China Cardiometabolic Disease and Cancer Cohort Study.A total of 105,922 community-dwelling adults aged≥40 years underwent the oral glucose tolerance test and uric acid assessment.The nonlinear relationships between glycemic indices and SUA levels were explored using generalized additive models.Results A total of 30,941 men and 62,361 women were eligible for the current analysis.Generalized additive models verified the inverted U-shaped association between glycemic indices and SUA levels,but with different inflection points in men and women.The thresholds for FPG,2 h-PG,and HbA1 c for men and women were 6.5/8.0 mmol/L,11.0/14.0 mmol/L,and 6.1/6.5,respectively(SUA levels increased with increasing glycemic indices before the inflection points and then eventually decreased with further increases in the glycemic indices).Conclusion An inverted U-shaped association was observed between major glycemic indices and uric acid levels in both sexes,while the inflection points were reached earlier in men than in women.  相似文献   
17.
Objective This study was performed to compare the genetic diversity, virulence, and antimicrobial resistance of Aeromonas strains isolated from patients and healthy individuals. Methods A total of 38 clinical strains and 19 strains from healthy individuals were isolated from the samples collected in Ma'anshan City, Anhui Province. Their taxonomy was investigated using concatenated gyrB-cpn60 sequences, and their resistance to 12 antibiotics was evaluated. The pathogenicity of these strains was examined through beta-hemolysis, protease activity, and virulence gene assays. Results The 57 Aeromonas strains were divided into 55 sequence types. Of these types, 21 were novel, suggesting that their genetic diversity was high. These Aeromonas isolates could be divided into 7 species, and the positive rates of beta-hemolysis and protease activity were 49.1% and 73.7%, respectively. The detection rate of clinical patients in terms of beta-hemolysis and protease activity was higher than that of healthy individuals. Among the four most common Aeromonas strains, A. dhakensis had the highest detection rate of virulence genes. The multidrug resistance rate of the clinical isolates was much higher than that of the strains isolated from healthy individuals. Conclusions The taxonomy, virulence properties, and antibiotic resistance of Aeromonas isolates from patients differ from those of the isolates from healthy individuals.  相似文献   
18.
Application of volatile anesthetics after brain ischemia provides neuroprotection in adult animals (anesthetic postconditioning). We tested whether postconditioning with sevoflurane, the most commonly used general anesthetic in pediatric anesthesia, reduced neonatal brain injury in rats. Seven-day-old Sprague–Dawley rats were subjected to brain hypoxia–ischemia (HI). They were postconditioned with sevoflurane in the presence or absence of 5-hydroxydecanoic acid, a mitochondrial KATP channel inhibitor. Sevoflurane postconditioning dose-dependently reduced brain tissue loss observed 7 days after brain HI. This effect was induced by clinically relevant concentrations and abolished by 5-hydroxydecanoic acid. These results suggest that sevoflurane postconditioning protects neonatal brain against brain HI via mitochondrial KATP channels.  相似文献   
19.
Achromobacter xylosoxidans is part of an emerging group of Gram negative bacterial infections with potentially severe sequelae, especially in the immunocompromised population such as burn patients. While antimicrobial therapy for patients with A. xylosoxidans bacteremia has been reported, the literature is scarce with regard to treatment in patients with positive tissue cultures only. Herein, we report our institution''s experience with such a case and a brief review of the current literature on this micro-organism in the setting of non-bacteremic infection.KEY WORDS: Achromobacter xylosoxidans, alcaligenes xylosoxidans, burn, tissue culture  相似文献   
20.

Purpose

To determine the risk factors of neurologic deficits during PVCR correction, so as to help improve safety during and after surgery.

Methods

A consecutive series of 76 patients with severe and rigid spinal deformities who were treated with PVCR at a single institution between October 2004 and July 2011 were included in our study. Of the 76 patients, 37 were male and 39 female, with an average age of 17.5 years (range 10–48 years). There were 52 adolescent patients (with an age <18 years) and 24 adult patients (with an age ≥18 years). Preoperatively, postoperatively and 6 months after surgery, we performed systemically neurologic function evaluations of each patients through meticulous physical examination. Any new abnormality or deterioration in evaluation of neurologic function than preoperative is reckoned postoperative neurologic deficits. Ten variables that might affect the safety of neurologic deficits during PVCR procedures, including imaging factors, clinical factors and operational factors, were analyzed using univariate analysis. Then the variables with statistical difference were analyzed by using multi-factor unconditional logistic regression analysis.

Results

No patient in this series had permanent paraplegia and nerve root injury due to operation. Change of neurologic status was found in six patients after surgery. Results of single-factor comparison demonstrated that the following seven variables were statistically different (P < 0.05): location of apex at main curve (X 3), Cobb angle at the main curve at the coronal plane (X 4), scoliosis associated with thoracic hyperkyphosis (X 5), level of vertebral column resected (X 6), number of segmental vessels ligated (X 7), preexisting neurologic dysfunction (X 8), and associated with intraspinal and brain stem anomalies (X 9). The multi-factor unconditional logistic regression analysis revealed that X 8 (OR = 49.322), X 9 (OR = 18.423), X 5 (OR = 11.883), and X 6 (OR = 8.769) were independent and positively correlated with the neurologic deficit.

Conclusions

Preexisting neurologic dysfunction, associated with intraspinal and brain stem anomalies, scoliosis associated with thoracic hyperkyphosis and level of vertebral column resected are independent risk factors for neurologic deficits during PVCR procedure.  相似文献   
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