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991.
Ebrahim AK Wadachi R Suda H 《Australian endodontic journal : the journal of the Australian Society of Endodontology Inc》2006,32(2):64-69
The aim of this in vitro study was to evaluate the accuracy of three electronic apex locators (EALs): Root ZX, Foramatron D10 and Apex NRG, in the detection of fractures in teeth having simulated horizontal and vertical root fractures. A total of 90 extracted intact, straight, single-rooted teeth were divided into six groups of 15 teeth each. In Groups A, B and C, an incomplete horizontal fracture was simulated by preparing a horizontal incision in the coronal, middle or apical portion of the root until the circumferential half of the canal was exposed in the horizontal plane respectively. In Groups D, E and F, an incomplete vertical root fracture was simulated by preparing a vertical straight incision to expose the canal in the coronal, middle or apical portion of the root all the way in the longitudinal plane respectively. The simulated fractures were 0.25 mm in thickness in all groups. The teeth were embedded in 1% agar and the canals were irrigated with saline solution during electronic measurement. Detection of the simulated root fractures was established with a size 10 K-file when the meter value reached 'APEX' on each EAL. In Groups A, B and C, Kruskal-Wallis tests revealed that there were no statistically significant differences between the three EALs. However, statistically significant differences were found among the EALs in Groups D, E and F (P < 0.0001, one-way anova and Tukey's post-hoc test). In conclusion, the three EALs tested were accurate and acceptable clinical tools in the detection of horizontal root fractures. However, the three EALs were unreliable in detecting the position of vertical root fractures. 相似文献
992.
993.
Adiponectin and adiponectin receptors in insulin resistance, diabetes, and the metabolic syndrome 总被引:38,自引:0,他引:38 下载免费PDF全文
Kadowaki T Yamauchi T Kubota N Hara K Ueki K Tobe K 《The Journal of clinical investigation》2006,116(7):1784-1792
Adiponectin is an adipokine that is specifically and abundantly expressed in adipose tissue and directly sensitizes the body to insulin. Hypoadiponectinemia, caused by interactions of genetic factors such as SNPs in the Adiponectin gene and environmental factors causing obesity, appears to play an important causal role in insulin resistance, type 2 diabetes, and the metabolic syndrome, which are linked to obesity. The adiponectin receptors, AdipoR1 and AdipoR2, which mediate the antidiabetic metabolic actions of adiponectin, have been cloned and are downregulated in obesity-linked insulin resistance. Upregulation of adiponectin is a partial cause of the insulin-sensitizing and antidiabetic actions of thiazolidinediones. Therefore, adiponectin and adiponectin receptors represent potential versatile therapeutic targets to combat obesity-linked diseases characterized by insulin resistance. This Review describes the pathophysiology of adiponectin and adiponectin receptors in insulin resistance, diabetes, and the metabolic syndrome. 相似文献
994.
Wijelath ES Rahman S Namekata M Murray J Nishimura T Mostafavi-Pour Z Patel Y Suda Y Humphries MJ Sobel M 《Circulation research》2006,99(8):853-860
We describe extracellular interactions between fibronectin (Fn) and vascular endothelial growth factor (VEGF) that influence integrin-growth factor receptor crosstalk and cellular responses. In previous work, we found that VEGF bound specifically to fibronectin (Fn) but not vitronectin or collagens. Herein we report that VEGF binds to the heparin-II domain of Fn and that the cell-binding and VEGF-binding domains of Fn, when physically linked, are necessary and sufficient to promote VEGF-induced endothelial cell proliferation, migration, and Erk activation. Using recombinant Fn domains, the C-terminal heparin-II domain of Fn (type III repeats 13 to 14) was identified as a key VEGF-binding site. Mutation of the heparin-binding residues on FnIII(13-14) abolished VEGF binding, and peptides corresponding to the heparin-binding sequences in FnIII(13-14) inhibited VEGF binding to Fn. Fn fragments containing both the alpha5beta1 integrin-binding domain (III 9 to 10) and the VEGF-binding domain (III 13 to 14) significantly enhanced VEGF-induced EC migration and proliferation and induced strong phosphorylation of the VEGF receptor and Erk. Neither the cell-binding or VEGF-binding fragment of Fn alone had comparable VEGF-promoting effects. These results suggest that the mechanism of VEGF/Fn synergism is mediated extracellularly by the formation of a novel VEGF/Fn complex requiring both the cell-binding and VEGF-binding domains linked in a single molecular unit. These data also highlight a new function for the Fn C-terminal heparin-binding domain that may have important implications for angiogenesis and tumor growth. 相似文献
995.
Satoh K Kagaya Y Nakano M Ito Y Ohta J Tada H Karibe A Minegishi N Suzuki N Yamamoto M Ono M Watanabe J Shirato K Ishii N Sugamura K Shimokawa H 《Circulation》2006,113(11):1442-1450
996.
Location of Early Colorectal Cancers at Fold-Top May Reduce the Risk of Lymph Node Metastasis 总被引:1,自引:0,他引:1
Pan W Terai T Abe S Sakamoto N Nagahara A Ohkusa T Ogihara T Sato N 《Diseases of the colon and rectum》2006,49(5):579-587
Purpose This study was designed to look for significant correlations between location of early colorectal cancer, distance from muscularis
mucosae to muscularis propria, and the frequency of lymph node metastasis.
Methods A total of 166 early colorectal cancers, including 67 surgically resected lesions, were evaluated. The cancers were divided
into two groups: metastatic and nonmetastatic. Cancer lesions were further subtyped at the fold-top or fold-bottom. Macroscopic
classifications and histology were performed. Absolute invasive depth and distance from muscularis mucosae to muscularis propria
was measured. Multivariate analysis was used to assess relationships among the variables.
Results The percentage of polypoid cancer lesions at fold-bottom was higher than at fold-top (74.5 vs. 51.8 percent), whereas flat-type cancer lesions at fold-bottom occurred less often than at fold-top (8.2 vs. 30.4 percent). Logistic regression showed that deep absolute invasive depth, lymphatic and vessel invasion, and cancer location
(at fold-bottom) were the significant risk factors for early colorectal cancers leading to lymph-node metastasis. The distance
from muscularis mucosae to muscularis propria with lymph-node metastasis (1,396.7 ± 728.4 μm) was shorter than without lymph-node
metastasis (3,533.9 ± 2,507.8 μm; P < 0.01). Multivariate analysis showed that distance from muscularis mucosae to muscularis propria was a statistically significant
factor for early colorectal cancers leading to lymph node metastasis (P = 0.0054).
Conclusions We conclude that early colorectal cancers at the fold-top or with a long distance from muscularis mucosae to muscularis propria
have less tendency to metastasize to lymph nodes. Clinically, these results provide evidence of a new indicator of endoscopic
mucosal resection for early colorectal cancers at the fold-top. 相似文献
997.
Many studies have suggested that human papillomavirus (HPV) infection plays an important role in the carcinogenesis of the cervical adenocarcinoma. However, the prevalence of HPV infection in cervical adenocarcinoma and adenosquamous carcinoma varies among the studies. Cervical adenocarcinoma (24 cases) and adenosquamous carcinoma (16 cases), including the underlying non-neoplastic epithelium were examined for HPV-DNA using in situ polymerase chain reaction (PCR), which enabled visualization of the localization on a glass slide. In adenocarcinoma, HPV-DNA was found in 13 cases (54%) and in eight cases in underlying non-neoplastic epithelium, resulting in a total of 21 positive cases (88%). In adenosquamous carcinoma, HPV-DNA was detected in 12 cases (75%) and and the HPV-DNA localization of each component was pure adenocarcinoma, 28.6%; mixed, 54.5%; and pure squamous cell carcinoma, 83.3%. In the underlying non-neoplastic epithelium, HPV-DNA was found more frequently in the squamous epithelium (73.3%) than the cervical glands (6.3%). In conclusion, HPV-DNA was detected in 54% of adenocarcinoma, and the rate was elevated by HPV localization in the underlying non-neoplastic epithelium. HPV infection in the underlying squamous epithelium might be related to the carcinogenesis, even in cervical adenocarcinoma. HPV-DNA localization was different in each component of adenosquamous carcinoma. 相似文献
998.
Yuri T Shimano N Ohashi Y Miki K Tsukamoto R Tsubura A 《Medical molecular morphology》2006,39(1):49-53
An autopsy case of a 19-year-old male Japanese student with a primary mixed choriocarcinoma and mature teratoma in the thymic
region is reported. The patient died 7 days after he first noticed fever and dyspnea. On autopsy, an anterior mediastinal
mass was found to be in contact with the thymic gland. The mass weighed 270 g and measured 12.5 cm × 10 cm × 5 cm. The left
thoracic cavity contained 2200 ml bloody pleural effusion and 200 g coagula due to hemorrhage from the tumor. Metastasized
choriocarcinoma was seen in both lungs and the liver. High serum levels of human chorionic gonadotropin (HCG, 1 634 000 mIU/ml)
and a decreased weight of the testes (2.0 g each) with Leydig cell hyperplasia/hypertrophy and the seminiferous tubules with
hyaline ghost tubules or Sertoli cell only tubules were seen; other male reproductive organs were histologically normal. Although
the serum testosterone level was within the normal range (5.75 ng/ml), luteinizing hormone (LH, 0.1 mIU/ml) and follicle-stimulating
hormone (FSH, 0.3 mIU/ml) levels were decreased. High serum levels of HCG and characteristic testicular changes are drscribed. 相似文献
999.
CAM5.2-positive subserosal myofibroblasts in appendicitis 总被引:2,自引:2,他引:0
Hamauzu T Kuroda N Guo L Miyazaki E Hayashi Y Toi M Hiroi M Enzan H 《Medical molecular morphology》2006,39(4):209-213
In this study, we examined the distribution and origin of myofibroblasts around the perforations of appendicitis. Stromal
cells of 45 cases were studied by immunohistochemistry. In the normal appendix, myofibroblasts were restricted to the mucosa,
and CD34-positive stromal cells were distributed in the submucosal and subserosal layers. Some mesothelial cells were positive
for cytokeratin CAM5.2, cytokeratin 5, or mesothelial cells (HBME-1). In perforation of appendicitis with both abscess and
granulation tissue, a small to moderate or a moderate to large number of myofibroblasts appeared in the subserosal area around
the perforation, respectively, but CD34-positive stromal cells were completely absent there. In the subserosal area of the
perforation of appendicitis with abscess, cytokeratin 5-positive stromal cells were absent. However, a small to moderate number
of cytokeratin CAM5.2-positive stromal cells were observed there. Double immunostaining showed the coexpression of alpha-smooth
muscle actin (ASMA) and cytokeratin CAM5.2 and the coexpression of cytokeratin 5 and cytokeratin CAM5.2 in many or some stellate-shaped
or spindle-shaped stromal cells existing in the subserosal area with granulation tissue around the perforation of appendicitis,
respectively. Finally, many myofibroblasts appearing in the subserosal area of the perforation of appendicitis may be derived
from submesothelial cells or mesothelial cells. 相似文献
1000.
Inspection by infection control team of the University Hospital, Faculty of Dentistry, Tokyo Medical and Dental University 总被引:1,自引:0,他引:1
Sunakawa M Matsumoto H Harasawa H Tsukikawa W Takagi Y Suda H 《Kōkūbyō Gakkai zasshi. The Journal of the Stomatological Society, Japan》2006,73(2):184-191
Factors affecting infection are the existence of infectious microorganisms, sensitivity of hosts, number of microorganisms, and infectious routes. Efforts to prevent infection focus on not allowing these factors to reach the threshold level. Inspection by an infection control team (ICT) of a hospital is one countermeasure for preventing nosocomial infection. We summarize here the problems for complete prevention of nosocomial infection based on the results of inspection by our ICT, so that staff working in the hospital can recognize the importance of preventing nosocomial infection. The following were commonly observed problems in our clinics found by the ICT : (1) incomplete practice of standard precautions and/or isolation precautions, (2) noncompliance with guidelines for the prevention of cross-infection, and (3) inappropriate management of medical rejectamenta. Infection control can be accomplished by strictly observing the standard precautions and isolation precautions. The ICT inspection round in the hospital could be an effective metaff working in the hod to clarify and overcome the problems involved in infection. 相似文献