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41.
42.
食管腺癌淋巴结转移与肿瘤侵及食管壁深度的关系 总被引:1,自引:0,他引:1
目的 对腺癌侵及食管壁深度与淋巴结转移的关系以及淋巴结转移对预后的影响进行分析研究.方法 澳大利亚弗林德斯大学医学中心自1985年~2003年,手术治疗食管腺癌121例.其中男101例,女20例.年龄36~80岁,平均62岁.本组手术切除率为96.7%(117/121例).手术清扫淋巴结的数目每例为2~30个,平均8个.无淋巴结转移59例(48.8%)、有淋巴结转移62例(51.2%).本组病例全部得到随访.结果 当肿瘤位于黏膜层或黏膜下层(T1)时,淋巴结转移的发生率为22.2%(10/45例)、平均淋巴结转移的个数为0.3个、>4个淋巴结转移的比例为0(0/45例);当肿瘤侵及食管周围组织(T4)时,淋巴结转移的发生率为85.7%(6/7例)、平均淋巴结转移的个数为5.1个、>4个淋巴结转移的比例为71.4%(5/7例),P<0.05.无淋巴结转移组的5年生存率为52.9%、1~4个淋巴结转移组的5年生存率为11.5%、>4个淋巴结转移组的5年生存率为0,P<0.01.结论 肿瘤对食管壁侵及深度和淋巴结转移的发生率及淋巴结转移的数量之间存在正相关性.随着肿瘤对食管壁侵及深度的增加,淋巴结转移的发生率、平均淋巴结转移的数量和>4个淋巴结转移的比例均增加.有无淋巴结转移和淋巴结转移的数量是影响远期生存率的一个重要因素. 相似文献
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44.
Guidotti T. L.; Watson L.; Wheeler M.; Jhangri G. S. 《Occupational medicine (Oxford, England)》1996,46(4):265-274
This is the first round in a series of surveys conducted inFort McMurray as part of the Fort McMurray Demonstration Projectin social marketing. This component of the survey was intendedto focus on the most prominent group of employed workers inthe community and to compare their patterns of response withthe community as a whole. Respondents to the survey were overwhelminglymale (96%), married (72.9%) and living in households of twoto five persons (87.9%). They were predominantly aged 30–44(55%) and graduates of high school (53.5%). Younger male workers(below age 30) were more likely to have a high school diploma(78.3%) or some additional technical or vocational training(21.7% compared to 12.5% overall) and to be unmarried or separated.Attitudes toward safety-related behaviours were stronger thanfor respondents from the community as a whole. Approximately70–100% of all age groups and both sexes showed strongagreement with attitudes involving child car seats and the unacceptabilityof drinking and driving. These attitudes include strong advocacyof vigorous enforcement of occupational health and safety standards.However, they showed a variability similar to the communityas a whole in behaviour at home compared to work, generallyreporting more consistent use of personal protection on thejob than in their own homes, particularly hearing protection.Even so, they were much less likely to perform stretching andwarm-up exercises prior to exertion than community residentsin general. The potential may exist to transfer the technologyand attitudes from workplace health and safety to communitysafety. One possible strategy to accomplish this is to involveworkers in this industry directly in community initiatives.This strategy may be generalizable to any community in whichthere are major employers who place a heavy emphasis on riskcontrol and occupational health and safety. 相似文献
45.
M. K. Watson L. S. Jakobson 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1997,117(2):273-280
In the present study, a kinematic analysis was made of unconstrained, natural prehension movements directed toward an object
approaching the observer on a conveyor belt at one of three constant velocities, from one of three different directions (head-on
or along the fronto-parallel plane coming either from the subject′s left or right). Subjects were required to grasp the object
when it reached a target located 20 cm directly in front of the hand′s start position. The kinematic analysis revealed that
both the transport and grasp components of the movement changed in response to the experimental manipulations, but did so
in a manner that guaranteed that, for objects approaching from a given direction, hand closure would begin at a constant time
prior to object contact (regardless of the object’s approach speed). The kinematic analysis also revealed, however, that the
onset of hand closure began earlier with objects approaching from the right than from other directions – an effect which would
not be predicted if time to contact was the key variable controlling the onset of hand closure. These results, then, lend
only partial support to the theory that temporal coordination between the transport and grasp components of prehension is
ensured through their common dependence on time to contact information.
Received: 20 September 1996 / Accepted: 16 June 1997 相似文献
46.
D. Levy D. A. Deporter R. M. Pilliar P. A. Watson N. Valiquette 《Clinical oral implants research》1996,7(2):101-110
It has previously been reported that porous‐coated root form endosseous dental implants, became well integrated when used in the traditional 2‐stage surgical approach. In this study, the placement of the implant in a 1‐stage (non‐submerged)technique was to be explored. Implants were placed in the mandibles of dogs, and 2 designs were used differing only in that one (experimental) had a 3mm transgingival extension, permitting it to be exposed lo the oral cavity from the outset. 12 (3 per animal) non‐submerged implants were placed on I side of 4 beagle dogs and 12 control (submerged) implants were placed contralaterally. All implants were allowed to heal for 6 weeks, after which histological preparations were made. 2 of 12 non‐submerged implants were lost due to post‐operative complications: otherwise, all implants healed uneventfully. Histomorphometric analysis revealed bone‐implant contact, as assessed by absolute bone contact (ABC) and contact length fraction (CLF). to be greater for the submerged design, suggesting that bone healing may be delayed with the non‐submerged approach. As well. at this early stage of healing, for both implant designs, ABC and CLF were significantly greater on proximal than on buccal and lingual aspects. 相似文献
47.
Pupil-sparing oculomotor nerve palsy generally results from extraaxial lesions, but it has also been seen with intraaxial infarcts and tumors. This report of a midbrain hemorrhage in a 64-year-old man supports the idea of selective interference with widely separated oculomotor nerve fascicles as the mechanism for intraaxial pupil-sparing oculomotor nerve palsies. 相似文献
48.
Identification of a gene essential for piliation in Haemophilus influenzae type b with homology to the pilus assembly platform genes of gram-negative bacteria. 总被引:8,自引:3,他引:5
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W J Watson J R Gilsdorf M A Tucci K W McCrea L J Forney C F Marrs 《Infection and immunity》1994,62(2):468-475
Haemophilus influenzae type b (Hib) pili are complex filamentous surface structures consisting predominantly of pilin protein subunits. The gene encoding the major pilin protein subunit of Hib adherence pili has been cloned and its nucleotide sequence has been determined. In order to identify specific accessory genes involved in pilus expression and assembly, we constructed isogenic Hib mutants containing insertional chromosomal mutations in the DNA flanking the pilin structural gene. These mutants were screened for pilin production, pilus expression, and hemagglutination. Pili and pilin production were assessed by immunoassays with polyclonal antisera specific for pilin and pili of Hib strain Eagan. Hemagglutination was semiquantitatively evaluated in a microtiter plate assay. Six Hib mutants produced proteins immunoreactive with antipilin antiserum but no longer produced structures reactive with antipilus antiserum. In addition, the mutants were unable to agglutinate human erythrocytes. Nucleotide sequence analysis localized the insertion sites in the six mutants to 2.5-kb open reading frame upstream of the pilin structural gene and immediately downstream of an Hib pilin chaperone gene. The amino acid sequence encoded by this open reading frame has significant homology to members of the pilus assembly platform protein family, including FhaA of Bordetella pertussis, MrkC of Klebsiella pneumoniae, and the Escherichia coli assembly platform proteins FimD and PapC. This open reading frame, designated hifC, appears to represent a gene essential to Hib pilus biogenesis that has genetic and functional similarity to the pilus platform assembly genes of other gram-negative rods. 相似文献
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