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71.

Objective

To examine the potential utility of 3D-reconstructed sonograms to distinguish cirrhotic from non-cirrhotic livers by demonstrating hepatic surface characteristics.

Materials and methods

A preliminary phantom study was performed to examine the potential resolution of 3D images, recognizing surface irregularities as a difference in height. In a prospective clinical study of 31 consecutive patients with ascites (21 cirrhosis, 10 non-cirrhosis), liver volume data were acquired by transabdominal mechanical scanning. The hepatic surface features of cirrhotic and non-cirrhotic patients were compared by 2 independent reviewers. Intra- and inter-operator/reviewer agreements were also examined.

Results

The phantom study revealed that 0.4 mm was the minimum recognizable difference in height on the 3D sonograms. The hepatic surface image was successfully visualized in 74% patients (23/31). Success depended on the amount of ascites; visualization was 100% with ascites of 10 mm or more between the hepatic surface and abdominal wall. The images showed irregularity of the hepatic surface in all cirrhotic patients. The surface appearance was confirmed as being very similar in 3 patients who had both 3D sonogram and liver resection for transplantation. The ability to distinguish cirrhotic liver from non-cirrhotic liver improved with the use of combination of 2D- and 3D-imaging versus 2D-imaging alone (sensitivity, p = 0.02; accuracy, p = 0.02) or 3D-imaging alone (sensitivity, p = 0.03). Intra-/inter-operator and inter-reviewer agreement were excellent (κ = 1.0).

Conclusion

3D-based sonographic visualization of the hepatic surface showed high reliability and reproducibility, acting as a virtual laparoscopy method, and the technique has the potential to improve the diagnosis of cirrhosis.  相似文献   
72.
Most karyophilic proteins are transported into the nucleus through the importin-mediated pathway. Importin alpha acts as a receptor for classical nuclear localization signal (NLS)-containing proteins. At present, the existence of several isoforms of importin alpha in mammals is known. In this study we report on the generation of a rat monoclonal antibody (MAb) 2D9 to importin alpha NPI-1 subfamily members (importin alpha5/NPI-1 and importin alpha7/S2) using the rat lymph node method and the characterization of this antibody. In several different cultured cell extracts, MAb 2D9 reacted to endogenous NPI-1 subfamily in Western blotting experiments. Epitope mapping using recombinant deletion mutants indicated that MAb 2D9 recognized arm motif in importin alpha5/NPI-1. Using immunofluorescence, MAb 2D9 detected NPI-1 subfamily in the cytoplasm of HeLa cells. Moreover, endogenous NPI-1 subfamily was dominantly localized in the nuclei of H(2)O(2)-treated HeLa cells, suggesting that NPI-1 subfamily accumulates in the nucleus in response to oxidative stress, like importin alpha1/Rch1.  相似文献   
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Patients who have been diagnosed as having acute pancreatitis should be, on principle, hospitalized. Crucial fundamental management is required soon after a diagnosis of acute pancreatitis has been made and includes monitoring of the conscious state, the respiratory and cardiovascular system, the urinary output, adequate fluid replacement and pain control. Along with such management, etiologic diagnosis and severity assessment should be conducted. Patients with a diagnosis of severe acute pancreatitis should be transferred to a medical facility where intensive respiratory and cardiovascular management as well as interventional treatment, blood purification therapy and nutritional support are available. The disease condition in acute pancreatitis changes every moment and even symptoms that are mild at the time of diagnosis may become severe later. Therefore, severity assessment should be conducted repeatedly at least within 48 h following diagnosis. An adequate dose of fluid replacement is essential to stabilize cardiovascular dynamics and the dose should be adjusted while assessing circulatory dynamics constantly. A large dose of fluid replacement is usually required in patients with severe acute pancreatitis. Prophylactic antibiotic administration is recommended to prevent infectious complications in patients with severe acute pancreatitis. Although the efficacy of intravenous administration of protease inhibitors is still a matter of controversy, there is a consensus in Japan that a large dose of a synthetic protease inhibitor should be given to patients with severe acute pancreatitis in order to prevent organ failure and other complications. Enteral feeding is superior to parenteral nutrition when it comes to the nutritional support of patients with severe acute pancreatitis. The JPN Guidelines recommend, as optional continuous regional arterial infusion and blood purification therapy.  相似文献   
76.
There are major differences in morphological detail after cutting the dentin surface among the methods commonly used to prepare dental cavities. The purpose of this study was to compare dentin permeability and the morphology of the dentin surfaces prepared with diamond and carbide steel burs after etching with 6% citric acid. Twenty-four freshly extracted human third molars were sectioned, mounted on plexiglass, and connected to the dentin-permeability measuring apparatus. The permeability of dentin was measured by fluid filtration and expressed as hydraulic conductance. There were two study groups of 12 teeth. Each tooth had one occlusal cavity preparation prepared but utilized three depths: the original was prepared just into the dentin, the second 0.5 mm deeper than the first, and the third 0.5 mm deeper than the second. One group had the first cavity prepared with a diamond, the second deepened using a steel bur, then the third depth was made by use of the diamond. The other group had the first cavity preparation prepared with a steel bur, deepened 0.5 mm again using a diamond, then deepened again using a steel bur. Dentin permeability was measured after cavity preparation, then after 2 minutes of acid etching. Analysis of variance and Duncan's multiple range test were used to establish whether differences were significant at the 0.05 confidence level. Prepared and acid-etched surfaces were characterized using a scanning electron microscope to identify any differences between the two groups. After acid etching with 6% citric acid, the permeability of dentin cavities prepared with diamond burs was significantly less than the permeability of cavities prepared with carbide steel burs. After etching, there were differences in the appearance of the dentin surfaces prepared with diamonds and steel burs. Dentin bonding agents may have their effectiveness reduced when placed following cavity preparation by use of a diamond.  相似文献   
77.
In colorectal cancer, to predict the response to chemo- and/or radio-therapy or the existence of lymph node metastasis preoperatively, a more competent diagnostic system is required, in addition to conventional diagnosis based on morphology and pathology. The application of gene expression profiling to preoperative cancer diagnosis using endoscopic biopsies could enable the selection of a more appropriate therapy for patients. In this study, we evaluated the feasibility of gene expression profiling using preoperative biopsies of colorectal tumors in a clinical setting, by investigating the influence of intra-tumor heterogeneity on the profiles and testing the prediction ability of tumor malignancy. Under endoscopic examination, two biopsies were sampled from each of 10 colorectal cancers and 10 adenomas, and their gene expression data were obtained using cDNA microarrays. The intra- and inter-tumor heterogeneities of the profiles were compared with unsupervised clustering analysis. Molecular prediction of tumor malignancy using biopsies was performed with the supervised classification algorithm. In clustering analysis, almost all paired biopsies from the same tumors joined each other. Pearson's correlation coefficients of the profiles between biopsies from the same tumors (mean, 0.83) were significantly greater than those of the profiles between biopsies from other cancers (mean, 0.58) (p<0.0001). In the supervised classification method, malignancy was correctly predicted in 39 out of 40 biopsies with 8-71 informative genes. Gene expression profiling using endoscopic biopsies of colorectal tumors revealed that the intra-tumor heterogeneity was smaller than the inter-tumor heterogeneity and tumor malignancy was correctly predicted. Our findings suggest that the technique of gene expression profiling accurately represents the biological properties of colorectal cancer and could help the preoperative diagnosis of this disease.  相似文献   
78.
The purpose of this study was to examine the efficacy of a combination treatment of sequential irinotecan and doxifluridine, an intermediate of capecitabine, evaluated by the response rate and safety in patients with metastatic colorectal cancer. In all, 60 metastatic colorectal cancer patients with measurable disease were enrolled. The schedule of the treatment consisted of a 90 min intravenous (IV) infusion of irinotecan 150 mg/m2 for on days 1 and 15, and 600–1,000 mg/body of oral doxifluridine on days 3–14 and 17–28. Cycles were repeated every 35 days. A median of three cycles of the combination therapy (range 1–14 cycles) was administered. A total of 57 patients (95%) completed at least two cycles of the therapy without any dose reductions. There was one complete response and 23 partial responses with an overall response rate of 40% [95% confidence interval (CI): 28–53%]. A total of 19 patients had stable disease, 43(72%) achieved disease control. The median time to progression was 5.9 months and the median overall survival was 20.5 months. Ten (17%) and 17 (28%) patients developed Grade 3–4 leukopenia and neutropenia, respectively. Grade 3–4 fatigue was observed in 7(12%) patients, nausea in five (8%), vomiting in four (7%), and diarrhea,in three (5%) patients. No treatment-related deaths were noted during the study. From these results, the combination of sequential irinotecan and doxifluridine is considered to be an effective, easy-to-administer regimen with acceptable tolerability.  相似文献   
79.
The relationship between nuclear DNA content determined by cytofluorometry in the primary focus of breast cancer and the survival rate was analyzed to clarify the prognostic significance of nuclear DNA content in breast cancer. The relationships of the ploidy pattern and the frequency of polyploid cells (4c or above) with the survival rate were studied in patients who underwent extended radical mastectomy and were comparable in the clinical stage and other prognostic factors. The survival rate was significantly lower in those of the non-diploid type showing no prominent peak at 2c or those in whom the frequency of polyploid cells was more than 30% than in those of the diploid type with a prominent peak at 2c or those showing few polyploid cells, even when the disease stage (Stage II by TNM classification and stage III by Tnm classification), histological lymph node metastasis (n (+), n1 beta), and histological type (papillotubular carcinoma, scirrhous carcinoma) were identical. From these findings, nuclear DNA content is considered to be a parameter of the malignancy of breast cancer and to have clinical significance as an important prognostic factor.  相似文献   
80.
Purpose

This study aimed to establish biomarkers to predict the progression of ossification by examining ossification volume and bone metabolism dynamics in patients with ossification of the posterior longitudinal ligament (OPLL).

Methods

We assessed OPLL progression using computed tomography-based three-dimensional (3D) image analysis and examined bone metabolism dynamics in 107 patients with OPLL (men, 72; women, 35; mean age, 63.6 years). The volume of OPLL was calculated twice during the follow-up period, and OPLL progression was evaluated by the annual rate of ossification increase. Bone metabolism dynamics were assessed by routine blood tests and analysis of various serum biomarkers (including 25-hydroxyvitamin D, intact parathyroid hormone, fibroblast growth factor 23, intact N-terminal propeptide of type 1, tartrate-resistant acid phosphatase isoform 5b, sclerostin, and Dickkopf-1) and bone mineral density (BMD). Patients were classified into the progression (P) or non-progression (NP) group according to the annual rate of increase in previous 3D image analyses, and associated factors between these groups were compared.

Results

The P and NP groups consisted of 29 patients (23 men and 6 women) and 78 patients (49 men and 29 women), respectively. Univariate analysis revealed significant differences in terms of age, body mass index, serum phosphorus, serum sclerostin, and BMD. In multivariate analysis, age, serum phosphorus, and serum sclerostin were identified as independent factors associated with OPLL progression.

Conclusion

Younger age, hypophosphatemia, and high serum sclerostin are risk factors for OPLL progression. Serum phosphorus and sclerostin could serve as important biomarkers for predicting ossification progression.

  相似文献   
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