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71.
72.
Use of the optimum finishing technique for an amalgam restoration may enhance the marginal integrity of the restoration and discourage its unnecessary early replacement. Two hundred and twenty-eight high copper amalgam restorations in 56 patients were evaluated, using clinical assessment criteria, up to three years after placement. Each patient had received at least one carved-only amalgam, at least one immediately finished restoration, and at least one amalgam that was polished at a subsequent appointment. Regardless of the finishing technique, the restorations exhibited similar marginal integrity up to three years after placement. Polished restorations were found to have substantially superior surface texture and less likelihood of surface discoloration. No evidence was found to support the use of immediate finishing techniques. The clinical significance of these findings, with respect to the need to polish amalgam restorations, is discussed. 相似文献
73.
74.
Technical and biological factors in disease-free survival after hepatic resection for colorectal cancer metastases. 总被引:18,自引:0,他引:18
B Cady M D Stone W V McDermott R L Jenkins A Bothe P T Lavin E J Lovett G D Steele 《Archives of surgery (Chicago, Ill. : 1960)》1992,127(5):561-8; discussion 568-9
Careful patient selection for hepatic resection of colorectal cancer metastases is essential to improve current poor results. Carcinoembryonic antigen level and number of metastases were significant preoperative prognostic indicators of 5-year disease-free survival in patients selected clinically for hepatic surgery. Surgical margin, weight of hepatic tissue resected, carcinoembryonic antigen level, and flow cytometry were significant postoperative prognostic indicators. Patients with a carcinoembryonic antigen level less than 200 ng/mL, 1-cm surgical margins, and less than 1,000 g of liver tissue removed had a greater than 50% estimated 5-year disease-free survival rate. If the metastases were diploid on flow cytometry, an additional survival advantage may have been gained. Inadequate surgical margins led to high rates of liver-only recurrence. Nonhepatic recurrence was unrelated to surgical margins. Intraoperative liver examination by ultrasound during primary colon cancer resection and adjuvant chemotherapy may offer earlier selection of biologically appropriate patients and improved outcome; both recommendations require clinical trials. 相似文献
75.
Richard Simpson Catherine Kennedy Hugh Carmalt Brian McCaughan David Gillett 《ANZ journal of surgery》1997,67(10):717-719
Background : A patient with a solitary pulmonary metastasis who had breast cancer in the past may benefit from pulmonary resection. Methods : Between 1984 and 1996, 17 patients underwent metastatectomy for metastatic breast cancer. There were 15 females and two males whose average age was 59 (range: 40–74 years). The median tumour-free interval after the primary breast-cancer operation was 5.1 years (range: 8 months-18.2 years). Sixteen patients had complete resections, which included six lobectomies and 10 lesser resections. Results : The postoperative mortality was nil and the morbidity rate was 6%. Follow-up was complete in all patients. Recurrent disease developed in four patients and two patients died of their disease. The 5-year survival was 62%. Conclusion : An aggressive surgical approach is warranted in patients with isolated resectable pulmonary metastases from breast cancer. 相似文献
76.
77.
Isabelle Ville Jean-François Ravaud Catherine Diard Henri Paicheler 《Sociology of health & illness》1994,16(3):301-321
In this paper a social constructionist approach is used to frame an analysis of the effects of physical impairment on self-perception. The results are reported of a recent study in which questionnaires were mailed to 314 people who were paraplegic and 284 who were post-polio, as well as to a control group of 327 who had no visible physical impairments. While the people who were paraplegic and those who made up the control group gave similar answers to most of the survey questions, those who were post-polio displayed a consistent, but different, way of reporting on their self-representations. Moreover, this discourse, which included such self-described characteristics as self-control, a sense of duty, and a concern for meticulousness, was consistent in the post-polio group across sex and age. It is concluded that the date of onset of physical impairment is significant in influencing the self-representation of persons with physical impairments. The socio-historical evolution of social practices and cultural expectations and norms with respect to persons with disabilities in Western cultures were taken into account in interpreting the results of this survey. 相似文献
78.
Mapping of α- and β-globin genes on Antarctic fish chromosomes by fluorescence in-situ hybridization
Eva Pisano Ennio Cocca Federico Mazzei Laura Ghigliotti Guido di Prisco H. William Detrich III Catherine Ozouf-Costaz 《Chromosome research》2003,11(6):633-640
The pathways and mechanisms of genomic change that have led to the peculiar haemoglobinless phenotype of the white-blooded
Antarctic icefishes (16 species in the family Channichthyidae) constitute an important model for understanding the rapid diversification
of the Antarctic notothenioid fish flock. To provide complementary structural information on genomic change at globin-gene
loci in Antarctic fish species, cytogenetic studies and in-situ chromosomal mapping have been undertaken. Using a DNA probe containing one α- and one β-globin gene from the embryonic/juvenile
globin gene cluster of the red-blooded species Notothenia coriiceps, we mapped the cluster on the chromosomes of Antarctic teleosts by fluorescence in-situ hybridization. As anticipated on the basis of its molecular organization, the cluster was located on a single chromosome
pair in all of the red-blooded fish species probed (N. coriiceps, N. angustata, Trematomus hansoni, T. pennellii). In contrast, the α/β-globin probe did not recognize complementary sequences on the chromosomes of the white-blooded species
Chionodraco hamatus and Channichthys rhinoceratus. These results represent the first example of chromosomal mapping of embryonic/juvenile globin genes in teleostean fishes.
Beyond its relevance to the evolutionary history of Antarctic notothenioids, this work contributes to our understanding of
the evolution of the chromosomal loci of globin genes in fishes and other vertebrates.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
79.
Over the last 40 years, the prevalence of smoking in the United States has declined from a peak of approximately 40% in 1965
to 20.9% in 2005. However, the rate of decline has leveled in recent years such that between 2004 and 2005 there was no decline
in smoking prevalence. The prevalence of smoking varies across subpopulations. Among adults, smoking prevalence is currently
highest among those aged 18 to 24 years (24.4%) and those aged 25 to 44 years (24.1%). Women are less likely to smoke than
men; however, the gender gap has narrowed over time. In immigrant populations, smoking prevalence increases with acculturation.
Although smoking prevalence varies widely by state, most states have had a decline over time. Rural populations have a higher
smoking prevalence than urban populations. If further reductions in the prevalence of smoking are to occur, vigilance and
targeted interventions in specific subpopulations will be crucial. 相似文献
80.
A new technique for measuring intraosseous pressures involves inserting a miniature transducer directly into the intraosseous space. A high-performance, high-fidelity pressure transducer is easy to assemble and insert. The transducer permits dynamic studies of intraosseous pressure during gait, and constitutes a promising tool for detecting changes in intraosseous pressure in osteoarthritis and osteonecrosis. 相似文献