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141.
A cephalometric study was conducted on 50 male and 54 female Sotho-Tswana children 11-16 years of age. The subjects were selected for excellence of occlusion and balance of facial proportions. Various analyses, including Steiner, Wits, and McNamara, were used for the evaluations. The mean measurements were compared with those of other Southern African Black groups and Caucasoids. Our study shows that cephalometric analyses for other groups cannot be used with confidence for the Sotho-Tswana people and our data provides norms for them. 相似文献
142.
The Dental Subscale of the Children's Fear Survey Schedule (CFSS-DS) is a well-known instrument for assessing dental fear in children. Previous studies have shown that the scale has acceptable reliability and validity. Factor analysis using scores of a group of Finnish schoolchildren resulted in three factors. No other data on the factor structure have been published. In order to report on the factor structure of the Dutch parental version of the CFSS-DS, the present study was undertaken. Factor analysis using scores from a group of Dutch children (n= 150) demonstrated a factor pattern fairly similar to the results found in the Finnish study. Three factors were found: 1) fear of highly invasive dental procedures, 2) fear of less invasive aspects of treatment and 3) fear of medical aspects. Considering that almost all items load substantially (> or =0.20) on more than one factor, it seems that one primary underlying dimension exists: fear of invasive treatment aspects. The CFSS-DS is proposed as a reliable, one-dimensional measure of dental fear. 相似文献
143.
We studied the interaction of azole antimycotics with intravenous (IV) and oral midazolam using a cross-over design in 12 volunteers, who ingested placebo, itraconazole, or fluconazole for 6 days. A 7.5-mg dose of midazolam was ingested on the first day, 0.05 mg/kg was administered IV on the fourth day, and 7.5 mg orally on the sixth day. Itraconazole reduced the clearance of IV midazolam by 69% and fluconazole reduced the clearance of IV midazolam by 51% (P < 0.001). A single dose of itraconazole and fluconazole increased the area under the oral midazolam concentration-time curve [AUC(0-infinity)] 3.5-fold (P < 0.001) and the peak concentration two-fold (P < 0.05) compared to placebo. On the sixth day the AUC(0-infinity) of oral midazolam was almost seven times greater with itraconazole (P < 0.001) and 3.6 times greater with fluconazole (P < 0.001) than without the antimycotics. The psychomotor effects of midazolam were also profoundly increased (P < 0.001). The psychomotor tests demonstrated only a weak interaction between the antimycotics and IV midazolam. When bolus doses of midazolam are given for short- time sedation, the effect of midazolam is not increased to a clinically significant degree by itraconazole and fluconazole, and it can be used in normal doses. However, the use of large doses of IV midazolam increases the risk of clinically significant interactions also after IV midazolam. Use of oral midazolam with itraconazole and fluconazole should be avoided. 相似文献
144.
The molecular mechanisms involved in luteolysis are still unclear in the primate. This study aimed to investigate the effect of induced luteolysis on the ovarian luteinizing hormone (LH) receptor and the steroidogenic enzyme, 3beta-hydroxysteroid dehydrogenase (3beta-HSD) in the marmoset monkey. Luteolysis was induced in the mid-luteal phase either directly by systemic prostaglandin F2alpha (PGF2alpha), or indirectly by LH withdrawal using systemic gonadotrophin releasing hormone antagonist (GnRHant) treatment. The LH receptor was studied by isotopic mRNA in-situ hybridization and in-situ ligand binding and 3beta-HSD expression was studied using isotopic mRNA in-situ hybridization and immunohistochemistry. Induced luteolysis was associated with a reduction in the expression of LH receptor (P < 0.0001) and 3beta-HSD mRNA, closely followed by a reduction in the LH receptor (P < 0.05) and 3beta-HSD protein concentrations within 24 h. There were no differences in the findings whether luteolysis was induced with PGF2alpha or GnRHant. This study shows that disparate mechanisms to induce luteolysis in the primate result in an identical rapid loss of the LH receptor and 3beta-HSD. In conclusion, induced luteolysis leads to rapid loss of the steroidogenic pathway in luteal cells. 相似文献
145.
PJ Klingler S Strolz C Profanter A Klingler D Kendler K Lhotta E Bodner G Riccabona 《Canadian Metallurgical Quarterly》1998,22(3):301-7; discussion 307-8
In an endemic goiter area patients with hyperparathyroidism (HPTH) frequently also have thyroid abnormalities. In a retrospective study of 95 patients with HPTH we assessed the diagnostic accuracy of imaging techniques (ultrasonography or radionuclide scanning) for preoperative localization of parathyroid adenomas. Altogether 86% of our patients had goiter, requiring thyroid resections in 37%. For 19 patients the parathyroid exploration was the second or third cervical operation, most of them due to goiter. We found that the overall rate of transient and permanent recurrent nerve paralysis is considerably increased in patients with previous neck surgery (26% vs. 7%). The combination of ultrasonography and radionuclide scanning can lead surgeons to the site of parathyroid lesions responsible for HPTH in 85% of cases, although frequent nodular goiters can produce pitfalls for correct imaging in iodine-deficient countries. In endemic goiter areas preoperative localization studies can be recommended in patients with primary HPTH--for evaluation of thyroid pathology possibly leading to resection or its accuracy in localizing parathyroid adenomas. These studies also seem justified in patients with previously unsuccessful neck explorations for HPTH. 相似文献
146.
The second epidermal growth factor (EGF)-like domain of human coagulation factor VII is a potent inhibitor of the FVIIa/tissue factor complex, the predominant initiator of coagulation in vivo. This domain has now for the first time been cloned and expressed in Escherichia coli as an affinity fusion protein. The fusion protein was secreted into the periplasm of E. coli and purified by affinity chromatography. The purified protein consisted of a fusion protein with the expected molecular weight, and in addition, a significant fraction of oligomers cross-linked by intermolecular disulfide bonds. Despite the presence of oligomers, the purified protein was a potent inhibitor of the extrinsic blood coagulation pathway with an IC50 value of about 20 microM. The biological activity was retained after liberation of the EGF domain by proteolytic cleavage. 相似文献
147.
148.
149.
G Velikova RE Banks A Gearing I Hemingway MA Forbes SR Preston NR Hall M Jones J Wyatt K Miller U Ward J Al-Maskatti SM Singh PJ Finan NS Ambrose JN Primrose PJ Selby 《Canadian Metallurgical Quarterly》1998,77(11):1857-1863
The concentrations of the soluble adhesion molecules E-cadherin, E-selectin, intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1) were investigated in 48 patients with colorectal cancer before treatment, and their relation to clinical, histological and routine laboratory parameters was examined. Data were collected on tumour stage at presentation, presence and sites of metastatic disease, tumour pathology and results of routine laboratory tests. Serum concentrations of ICAM-1 and VCAM-1 were significantly elevated in the patients with colorectal cancer in comparison with a group of healthy subjects (P < 0.00001). Levels of circulating ICAM-1 and VCAM-1 were increased both in patients with local and those with metastatic disease. Although elevated in some patients soluble E-cadherin and E-selectin concentrations were not significantly elevated compared with the control group (P = 0.71 and P = 0.052 respectively). The levels of circulating ICAM-1 were significantly correlated with those of VCAM-1 and E-selectin. A correlation was also found between the serum concentrations of E-selectin and ICAM-1 and alkaline phosphatase, total white cell count and platelet count. VCAM-1 was positively correlated with age and negatively with degree of tumour differentiation and haemoglobin concentration. The biological implications and possible clinical relevance of these findings are discussed. 相似文献
150.
AD Levi WG Choi PJ Keller JE Heiserman VK Sonntag CA Dickman 《Canadian Metallurgical Quarterly》1998,23(11):1245-50; discussion 1251
STUDY DESIGN: Seven cadaveric cervical spines were implanted with a porous tantalum spacer and a titanium alloy spacer, and their radiographic and imaging characteristics were evaluated. OBJECTIVE: To determine the radiographic characteristics of porous tantalum and titanium implants used as spacers in the cervical spine. SUMMARY OF BACKGROUND DATA: Anterior decompressive surgery of the disc space or the vertebral body creates a defect that frequently is repaired with autologous bone grafts to promote spinal fusion. Donor site morbidity, insufficient donor material, and additional surgical time have spurred the development of biomaterials to replace or supplement existing spinal reconstruction techniques. Although the promotion of a solid bony fusion is critical, the implanted biomaterial should be compatible with modern imaging techniques, should allow visualization of the spinal canal and neural foramina, and should permit radiographic assessment of bony ingrowth. METHODS: Cadaveric spines containing the implants were imaged with plain radiography, computerized tomography, and magnetic resonance imaging. The image distortion produced by the implants was determined qualitatively and quantitatively. RESULTS: The tantalum and titanium spacers were opaque on plain radiographic films. On computed tomographic scans, more streak artifact was associated with the tantalum implants than with the titanium. On magnetic resonance imaging, the porous tantalum implant demonstrated less artifact than did the titanium spacer on T1- and T2-weighted spin echo and on T2*-weighted gradient-echo magnetic resonance images. Overall, the tantalum implant produced less artifact on magnetic resonance imaging than did the titanium spacer and therefore allowed for better visualization of the surrounding bony and neural structures. CONCLUSION: The material properties of titanium and porous tantalum cervical interbody implants contribute to their differential appearance in different imaging methods. The titanium implant appears to image best with computed tomography, whereas the porous tantalum implant produces less artifact than does the titanium implant on several magnetic resonance imaging sequences. 相似文献