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Skeletal scintigraphy following incidental trauma   总被引:3,自引:0,他引:3  
Kim  HR; Thrall  JH; Keyes  JW  Jr 《Radiology》1979,130(2):447
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Objective

The placement of orthodontic bands usually increases plaque accumulation due to numerous mechanical retention sites. The purpose of this investigation was to evaluate the amount and distribution pattern of biofilm in the oral (palatal and lingual) and interproximal regions surrounding orthodontic bands.

Materials and Methods

We evaluated the formation of biofilm on 32 orthodontic bands which had been placed intraorally for 6?C37?months. Two parameters were measured: the percentage of surface covered by biofilm (quantity) and the biofilm distribution pattern of accumulation. We measured these two parameters in four regions of interest: the mesial and distal interproximal regions, as well as the mesial and distal regions of the oral attachment.

Results

The quantity of biofilm formation was similar in all four regions of interest, ranging from 13.3% to 16.8%. In contrast to biofilm quantity, distribution patterns differed in the four regions. In the mesial and distal interproximal regions it appeared as extensive insular areas in 87.5% and 71.9%, respectively, whereas it appeared more often supragingival and linear in nature in regions adjacent to the oral attachment, i.e. in 65.6% and 68.8%, respectively.

Conclusion

Our results indicate that firstly, oral hygiene in the palatal and lingual regions of orthodontic bands seems as difficult as it is in the interproximal areas, thus requiring thorough hygiene in both areas. Secondly, orthodontic patients with a history of periodontal disease require special attention regarding the use of orthodontic bands.  相似文献   
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Background

Endothelial progenitor cells (EPC) which are characterised by the simulateous expression of CD34, CD133 and vascular endothelial growth receptor 2 (VEGF 2) are involved in the pathophysiology of congestive heart failure (CHF) and their number and function is reduced in CHF. But so far our knowledge about the number of circulating hematopoietic stem/progenitor cells (CPC) expressing the early hematopoietic marker CD133 and CD34 in CHF is spares and therefore we determined their number and correlated them with New York Heart Association (NYHA) functional class.

Methods

CD34 and CD133 surface expression was quantified by flow cytometry in the peripheral venous blood of 41 healthy adults and 101 patients with various degrees of CHF.

Results

CD34+, CD133+ and CD34+/CD133+ cells correlated inversely with age. Both the number of CD34+ and of CD34+/CD133+ cells inversely correlated with NYHA functional class. The number of CD133+ cells was not affected by NYHA class. Furthermore the number of CD133+ cells did not differ between control and CHF patients.

Conclusion

In CHF the release of CD34+, CD133+ and CD34+/CD133+ cells from the bone marrow seems to be regulated differently. Modulating the releasing process in CHF may be a tool in CHF treatment.  相似文献   
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目的 :寻找具有正性肌力活性的化合物。方法 :根据文献报道的二氢喹啉酮类正性肌力药物的结构特点 ,设计、合成了其类似物。以苯胺为起始原料经多步合成 ,对所得化合物用离体豚鼠心脏与主动脉观察了心肌收缩力、扩血管作用及心率。结果 :合成了 1 0个 6 ( 4 酰基 1 哌嗪乙酰氨基 ) 3 ,4 二氢 2 ( 1H) 喹啉酮类化合物 ( 4a~ 4j) ,均为未见文献报道的化合物。结论 :初步药理试验表明 ,化合物 ( 4h)显示了正性肌力及扩血管活性。  相似文献   
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Eruptive syringoma is a very rare variant of syringoma. It is a benign adnexal tumor of the intraepidermal portion of eccrine sweat ducts. Here we report a 32-year-old female presented with classical asymptomatic eruptive syringomas involving her face and extremities.  相似文献   
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Background: Spinal anaesthesia for caesarean section may cause hypotension, jeopardizing the foetus and its mother. We aimed to identify the spectrum of definitions of hypotension used in the scientific literature. In a second part, we applied these definitions to a prospective cohort in order to evaluate the effect of different definitions on the incidence of hypotension. Methods: A systematic literature search in PubMed was performed from 1999 to 2009 with the search terms ‘hypotension’ and ‘caesarean section’. Consecutive parturients undergoing caesarean section under spinal anaesthesia were included in a prospective study. Results: Sixty‐three eligible publications (7120 patients) were retrieved, revealing 15 different definitions of hypotension. A decrease below 80% baseline and the combined definition of a blood pressure below 100 mmHg or a decrease below 80% baseline were the two most frequent definitions, found in 25.4% and 20.6% of the papers, respectively. When applying the spectrum of definitions to a prospective cohort, the incidences of hypotension varied between 7.4% and 74.1%. The incidence increased from 26.7% to 38.5% when using a value below 75% of baseline instead of below 70% of baseline. Conclusion: There is not one accepted definition of hypotension in the scientific literature. The incidence of hypotension varies depending on the chosen definition. Even minor changes of the definition cause major differences in the frequency of hypotension. This makes it difficult to compare studies on interventions to treat/prevent hypotension and probably hampers progress in this area of research.  相似文献   
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