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31.

Objective:

The aim of this study was to evaluate the degree of microbial contamination in packaged gutta-percha cones before and during use in clinical conditions.

Material and Methods:

Sealed packages of #15-40 gutta-percha cones were opened under aseptic laboratory conditions. Two gutta-percha cones from each size were randomly drawn and added to tubes containing glass beads and 750 μL of saline. The tubes were vortexed, serially diluted and samples of 250 μL were cultured on agar plates. The plates were incubated at 37°C for 3 days and colonies were counted. The initially sampled packages were distributed to 12 final year dental students. The packages were collected at the end of the first and the third clinical practice days and sampled as described above.

Results:

Baseline microbial counts did not exceed 3 CFU. At the end of the first and the third day, additional contamination was found in five and three of the packages, respectively. The ratio of contaminated packages at the first day and the third day was not significantly different (z-test; p > 0.05). The numbers of microorganisms cultured at the first day (8 ± 9.9 CFU) and the third day (4.5 ± 8.3 CFU) were not significantly different (Wilcoxon signed-rank test; p > 0.05). No significant correlation was found between the number of filled root canals and cultured microorganisms at either the first day (Spearman''s rho; r = 0.481, p = 0.113) or the third day (r = -0.034, p = 0.917).

Conclusions:

Gutta-percha cones taken directly from manufacturer''s sealed package harbored microorganisms. Clinical use of the packages has been found to be associated with additional contamination of the gutta-percha cones. The counts of cultured microorganisms did not correlate well with the number of filled root canals.  相似文献   
32.
AIM: To examine skin perfusion in dependency on insulinemia in healthy subjects.METHODS: All volunteers were informed in detail about the procedures and signed informed consent. The protocol of this study was approved by the ethical committee. In our study, a two stage hyperinsulinemic euglycemic clamp was performed, with insulinemia 100 and 250 mIU/mL and glycemia 5.0 mmol/L (3% standard deviation). Before the clamp and in steady states, microcirculation was measured by laser Doppler flowmetry and transcutaneous oximetry and energy expenditure was measured by indirect calorimetry. Results (average and standard deviation) were evaluated with paired t-test.RESULTS: Physiological (50 mIU/L) insulinemia led to higher perfusion in both tests; hyperemia after heating to 44%-1848% (984-2046) vs 1599% (801-1836), P < 0.05, half time of reaching peak perfusion after occlusion release 1.2 s (0.9-2.6) vs 4.9 s (1.8-11.4), P < 0.05. Supraphysiological (150 mIU/L) insulinemia led to even higher perfusion in both tests; hyperemia after heating to 44%-1937% (1177-2488) vs 1599% (801-1836), P < 0.005, half time to reach peak perfusion after occlusion release 1.0 s (0.7-1.1) vs 4.9 s (1.8-11.4), P < 0.005. A statistically significant increase occurred in tissue oxygenation in both insulinemia. The difference in perfusion and oxygenation between physiological and supraphysiological hyperinsulinemia was not statistically significant.CONCLUSION: The post occlusive hyperemia test in accordance with heating test showed significantly increasing skin perfusion in the course of artificial hyperinsulinemia. This effect rises non-linearly with increasing insulinemia. Dependency on the dose was not statistically significant.  相似文献   
33.
The occurrence of membranous nephropathy in pediatric series of systemic lupus erythematosus has been reported only rarely, probably due to a very low frequency. One hundred fifty-four children who were seen in 100 French pediatric centers between January 2002 and April 2005 were included. Fifteen (12 girls and three boys) out of the 81 (18.5 %) children with renal involvement presented histological features of membranous nephropathy. Their ages ranged from six to 15 years old (mean=11.3) at the age of SLE diagnosis and 8/15 children were of African origin. Isolated membranous nephropathy was observed in nine patients, of whom five patients displayed a complete recovery following immunosuppressive treatment. Associated proliferative lesions were observed on the first kidney specimen in two patients and in a further renal biopsy in four other patients, leading to a less favorable course of lupus nephropathy.  相似文献   
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摘要 背景:微囊化已经普遍应用于各种实验研究,微囊包裹的干细胞治疗糖尿病问题也成为当今的热点,但是囊内包裹的细胞浓度与胰岛素释放量的关系成为目前需要解决的问题之一。 目的:运用海藻酸钠-多聚赖氨酸-海藻酸钠微囊包裹胰岛素产生细胞,观察细胞浓度对胰岛素和C肽释放情况的影响。 方法:制备大鼠胰腺损伤提取物,将小鼠骨髓间充质干细胞诱导分化为胰岛素产生细胞。免疫荧光和双硫腙染色鉴定诱导后细胞内胰岛素的表达。然后将胰岛素产生细胞制成浓度分别为1×107 L-1,5×107 L-1,1×108 L-1,5×108 L-1,1×109 L-1,5× 109 L-1的细胞悬液,气体吹喷法制成微囊,用6-羧基乙二酸荧光素检测囊内细胞活力,用葡萄糖刺激微囊内细胞检查其胰岛素和C肽的分泌情况。 结果与结论:胰腺损伤提取物诱导后双硫腙染色和细胞免疫荧光鉴定出胰岛素产生细胞内有胰岛素的表达;胰岛素产生细胞制成的微囊直径约为400 µm,大小均一,6-羧基乙二酸荧光素检测到囊内细胞的活力很好。用葡萄糖刺激不同细胞浓度的微囊,发现细胞浓度为1×108 L-1时,胰岛素和C肽的分泌达到最高。 关键词:微囊化;骨髓间充质干细胞;胰岛素产生细胞;胰岛素;C肽 doi:10.3969/j.issn.1673-8225.2011.03.046  相似文献   
36.
A multidisciplinary study on pre-cancerous and early cancerous lesions of uterine cervix was carried out at our Institute from which the subjects (cases and one group of control) for the present study were selected with the objective to identify the possible risk factors related to high-grade cervical lesions including invasive cancer through an epidemiological study by selecting two different types of controls and to assess the feasibility whether the cancers of other organs could be taken as controls at the same time studying the risk factors associated with cervical cancer. One group of control was women with negative Pap smear and second group of control was the women with breast cancer but negative Pap smear. A total of 100 biopsy-proven cases of high-grade cervical intraepithelial lesions and Invasive cancer were recruited. The results of the study show that some of the risk factors associated with the cervical cancer get exaggerated when breast cancer cases were used as controls because risk factors of both cancers are opposite to each other. So it is concluded that in order to remove any bias, normal hospital controls or controls selected from multiple cancers should be taken to study the risk factors involved in cervical carcinogenesis.  相似文献   
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The authors report on a boy with typical course of recent nephrotic syndrome, who developed massive thrombosis involving the iliac inferior holden veins during the standard therapy with corticosteroid. The first sign of this complication was pulmonary embolism. Thrombosis was treated by surgery, during which 3 large thrombi from veins were removed. The patient developed recurrent thrombosis occurring at the previous sites in the later stage and he died 23 days after the first sign of thromboembolic complication. Autopsy showed only minimal glomerular changes. The cause of the death was massive pulmonary embolisation. The aethiopathogenesis of the complication and preventive approach in children with nephrotic syndrome are discussed.  相似文献   
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Cervical pregnancy in Asherman's syndrome   总被引:1,自引:0,他引:1  
  相似文献   
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