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31.
S. H. Kim J. W. Milsom J. M. Church K. A. Ludwig A. Garcia-Ruiz J. Okuda V. W. Fazio 《Surgical endoscopy》1997,11(10):1013-1016
Background: Because of the inability to palpate colonic tumors during laparoscopy, their location must be precisely identified before
resection is undertaken.
Method: A retrospective study was performed of 58 patients in order to be able to describe our methods of tumor localization for
laparoscopic colorectal operations and to review their effectiveness.
Results: In all patients, the entire colon was examined preoperatively by colonoscopy. In one patient, preoperative colonoscopic localization
was inaccurate. In 31 patients, tumors were easily detectable at surgery. In five patients with the tumor in the right colon,
even though the lesion was not detectable at surgery, right colectomy was performed without marking because preoperative colonoscopy
reliably identified the lesion adjacent to the ileocecal valve. Twenty-two patients required some type of procedure to localize
the tumor. The procedures and their problems were as follows: preoperative tattoo (five)—tattoo not visualized (one); intraoperative
colonoscopy alone (six), combined with intraoperative tattoo (four) or clip (three)—poor operative exposure due to bowel distension
(nine), hard to see the clip (three), dislodged clip (two), inadequate resection margin (one); intraoperative proctoscopy
alone (two), combined with laparoscopic stitch (two)—no problems. In no patient was tumor present at a resection line and
in no patient was the wrong segment resected.
Conclusions: Reliable preoperative identification of the tumor adjacent to the ileocecal valve can permit right colectomy without marking.
Lesions in the upper rectum can be approached via intraoperative proctoscopy ± suture placement. If the surgeon anticipates
intraoperative localization may be difficult, lesions other than rectal or cecal ones should probably be marked by preoperative
tattooing. Further studies regarding the technique of tattooing are warranted.
Received: 18 July 1996/Accepted: 10 March 1997 相似文献
32.
The ability to compare various results that measure clinical deficits and outcome is a necessity for successful worldwide
discussion about cervical spondylogenic myelopathy (CSM) and its treatment. There is hardly any information in literature
how to value and compare outcome assessed by different scores. In a retrospective study we objectively evaluated the Nurick-score,
Japanese-orthopaedic-association-score (JOA-Score), Cooper-myelopathy-scale (CMS), Prolo-score and European-myelopathy-score
(EMS) using the data of 43 patients, all of whom showed clinical and morphological signs of CSM and underwent operative decompression.
The scores were assessed pre- and postoperatively. The correlation between the score-results, anamnesis, clinical and diagnostic
data was investigated. All the scores show a statistically significant correlation and measure postoperative improvement.
With exception of the Prolo-score all scores reflect clinical deficits of CSM. The Prolo-score rates the severity of CSM on
the state of the economic situation above clinical symptoms. The main differences of the scores are shown in the number of
patients showing postoperative improvement, varying between 33% (Nurick-score) and 81% (JOA-score). The recovery-rates, as
a measure of the cumulative improvement of all the symptoms, show less variation (23–37%). The differences of the recovery-rate
were only statistically significant between JOA-score, Nurick-score and EMS (P < 0.05), whereas all the other scores showed no significant differences. To assess the postoperative successes, the evaluation
of the recovery-rate is essential. There is no significant difference in the recovery-rate amongst the majority of the scores,
which allows a good comparison of the results from different studies. Nevertheless, it is always important to differentiate
the therapy results of CSM published worldwide. 相似文献
33.
Ivan Bednar Xiao Zhang Ramez Dastranj-sedghi Agneta Nordberg 《International journal of developmental neuroscience》1998,16(7-8):661-668
The basal forebrain cholinergic neurons are implicated in the pathogenesis ofneurodegenerative diseases including Alzheimerfn2s disease (AD). The nicotinic acetylcholine receptors (nAChRs) have been found to besignificantly afflicted in AD. To study the underlying mechanisms for dysfunction of the basalforebrain cholinergic neurons development of suitable animal models is warranted. In this studywe investigated the effects of bilateral lesions of the nucleus basalis magnocellularis on nAChRs inthe rat brain using the cholinergic system selective immunotoxin 192-IgG saporin andnon-selective excitotoxin ibotenic acid. Changes in nAChRs were measured by 3H-cytisineand 3H-epibatidine, two ligands with different selectivity for nAChRs subtypes. Inthe parietal cortex of ibotenic acid lesioned rates, the choline acetyltransferase activity (ChAT)was decreased by 24% while no changes were detected in the frontal cortex or hippocampus.Similarly, a 40% decrease was observed in the number of nAChRs labelled by 3H-cytisine,but not by 3H-epibatidine, in the parietal cortex, while no changes were found in thefrontal cortex or hippocampus. Although the 192-IgG saporin induced lesions reduced the ChATactivity in the frontal cortex, parietal cortex and hippocampus by 77, 50 and 21%, respectively, nochanges were observed in the number of nAChRs as studied by 3H-cytisine or 3H-epibatidine. The results indicate a difference in vulnerability of the cortical nAChRsubtypes to experimental lesions of the nucleus basalis magnocellularis. The findings in this studysuggest that a major portion of the nAChRs might be located on non-cholinergic neurons in thebrain. 相似文献
34.
Digital subtraction arthrography in preoperative evaluation of painful total hip arthroplasty 总被引:1,自引:0,他引:1
A. Z. Ginai F. C. van Biezen P. A. M. Kint H. Y. Oei W. C. J. Hop 《Skeletal radiology》1996,25(4):357-363
Objective. The objective of this clinical study was to define the diagnostic value of plain radiography, digital subtraction arthrography
and two-phase bone scintigraphy in patients with clinically loose or infected hip prostheses. Design. Digital subtraction arthrograms, scintigrams and plain radiographs of 70 consecutive patients who underwent revision hip arthroplasty
were scored individually and in masked fashion for the presence or absence of features indicating loosening of femoral and/or
acetabular components. The operative findings acted as the gold standard. Results. Digital subtraction arthrography was best (P<0.001) for predicting a loose acetabular component, while no significant additional predictive value was found for plain
radiographs (P=0.24) and scintigraphy (P=0.27). Digital subtraction arthrography was also the most important modality for predicting a loose femoral component (P=0.001), while the plain radiograph was of significant (P=0.04) additional value and scintigraphy was of no additional value (P=0.13) on multivariate analysis. Conclusion. Digital subtraction arthrography gives the best results in the prediction of loosening of acetabular and femoral components.
Plain radiographs give additional information on loosening of the femoral component, but scintigraphy offers no additional
advantage. 相似文献
35.
Many eukaryotic cells depend on proper cell polarization for their development and physiological function. The establishment of these polarities often involve the subcellular localization of a specific subset of proteins, RNAs and organelles. In Drosophila, the microtubule-dependent BicD (BicaudalD) localization machinery is involved in the proper localization of mRNA during oogenesis and embryogenesis and the proper positioning of the oocyte and photoreceptor nuclei. BicD acts together with the minus-end directed motor dynein as well as Egl and Lis-1. The finding that the mammalian homologs of BicD function in retrograde Golgi-to-ER transport has supported the view that BicD may be part of a repeatedly used and evolutionary conserved localization machinery. In this review we focus on the various processes in which BicD is involved during Drosophilian development and in mammals. In addition, we evaluate the interactions between BicD, the dynein localization machinery and associated factors. 相似文献
36.
Porcine circovirus type 1 (PCV1) encodes two major ORFs. The cap gene comprises the major structural protein of PCV, the rep gene specifies Rep and Rep', which are both essential for initiating the replication of the viral DNA. Rep corresponds to the full-length protein, whereas Rep' is a truncated splice product that is frame-shifted in its C-terminal sequence. In this study, the cellular localization of PCV1-encoded proteins was investigated by immune fluorescence techniques using antibodies against Rep, Rep' and Cap and by expression of viral proteins fused to green and red fluorescence proteins. Rep and Rep' protein co-localized in the nucleus of infected cells as well as in cells transfected with plasmids expressing Rep and Rep' fused to fluorescence proteins, but no signal was seen in the nucleoli. Rep and Rep' carry three potential nuclear localization signals in their identical N-termini, and the contribution of these motifs to nuclear import was experimentally dissected. In contrast to the rep gene products, the localization of the Cap protein varied. While the Cap protein was restricted to the nucleoli in plasmid-transfected cells and was also localized in the nucleoli at an early stage of PCV1 infection, it was seen in the nucleoplasm and the cytoplasm later in infection, suggesting that a shuttling between distinct cellular compartments occurs. 相似文献
37.
Yoshimitsu Fukushima Keiko Wakui Toshiro Nishida Yasuo Ueoka 《American journal of medical genetics. Part A》1991,40(4):485-487
We report on a boy with the blepharophimosis sequence and de novo, apparently balanced reciprocal translocation between 3q23 and 4p15.2 [46, XY,t(3;4)(q23;p15.2)de novo]. Possible assignment of this autosomal dominant disorder is discussed. A 3q23 band is a more preferable gene locus of the blepharophi mosis sequence, based on the comparison of clinical manifestations between 4p- and 3q-syndromes. 相似文献
38.
Summary The mitochondrial DNA from seven species of the aquatic phycomycete Allomyces has been isolated and characterized by restriction enzyme analysis. Comparison of the mitochondrial DNA restriction enzyme fragmentation patterns showed pronounced differences not only among species but also among four isolates of A. arbuscula. The mitochondrial DNAs range in size from 39 kbp in A. neo-moniliformis to 56 kbp in A. macrogynus.A physical map of the mitochondrial DNA of Allomyces arbuscula strain Costa Rica 21 has been constructed. The genome is circular and has a size of 49.2 kbp. The genes coding for the small and large ribosomal RNAs, cytochrome oxidase subunits 1, 2, and 3, apocytochrome b, and ATPase subunits 6 and 9 were localized in the mitochondria) DNA by heterologous hybridization with specific mitochondria) gene probes from Saccaromyces cerevisiae and Neurospora crassa. Comparison of the gene map of the closely related species Blastocladiella emersonii with that of A. arbuscula indicates a similar gene order in the two organisms. 相似文献
39.
SH2A 基因对细胞信号转导的影响及其亚细胞定位 总被引:3,自引:0,他引:3
目的 研究Src同源域2(src homology 2,SH2)A基因在细胞信号转导中的作用并进行亚细胞定位。方法 通过RT—PCR方法扩增SH2A cDNA编码序列,构建真核重组表达载体pcDNA3.1-SH2A,利用脂质体转染肝癌Bel7402细胞、COS7细胞,检测蛋白酶C(protein kinaseC,PKC)、酪氨酸蛋白激酶(tyrosine protein kinase,TPK)、丝裂原激活蛋白激酶(mitogen activated protein kinase,MAPK)活性的改变;另构建pEGEP—SH2A,转染同前,荧光显微镜观察荧光定位。结果 测序结果显示真核重组表达载体pcDNA3.1-SH2A及pEGFP—SH2A中均含有SH2AcDNA编码序列;肝癌Bel7402细胞、COS7细胞转染pcDNA3.1-SH2A后,胞浆PKC的活性下降了40%左右,MAPK和TPK活性未见明显改变。荧光显微镜观察发现SH2A基因在细胞质中表达。结论 SH2A基因编码蛋白在PKC信号转导通路中起抑制作用;SH2A基因编码蛋白定位于细胞质。 相似文献
40.
脑电(Electroencephalography, EEG)和功能磁共振(Functional magnetic resonance imaging, fMRI)技术的结合,可以实现两者优势的互补,获得更加合理的源定位结果.本文报道的是一种将fMRI先验信息结合到脑电源定位中的新方法.在该方法中,先利用SPM方法计算获得fMRI的统计映射参数,然后将基于计算获得的统计参数构造的权矩阵结合到FOCUSS的迭代过程中,对脑电的反演提供具有fMRI先验空间位置信息的约束,提高脑电的源空间定位精度,从而获得更加合理的定位结果.通过对一形状知觉实验fMRI和脑电数据的结合定位分析,结果初步证实了改进方法能获得和生理更加一致的结果. 相似文献