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81.
Human SART-1 ( hSART-1 ) gene encodes a 125 kD protein with a leucine-zipper motif expressed in the nucleus of all proliferating cells, and a 43 kD protein expressed in the cytosol of most epithelial cancers. In this study, two rodent genes ( rSART-1 and mSART-1 ) homologous to hSART-1 were cloned from cDNA libraries of murine brain and a rat tumor cell line, respectively. mSART-1 and rSART-1 were highly homologous to hSART-1 with 86% and 84% identity at the nucleotide level, and 95% and 91% at the protein level, respectively. The leucine zipper domain and two basic amino acid portions that bind DNA, as well as peptide sequences recognized by human cyto-toxic T lymphocytes (CTLs), were all conserved in these rodent genes. Nuclear protein homologous to the 125 kD hSART-1800 protein, but not to the 43 kD cytosol SART-1259 protein, was detectable with specific antibody in the nuclear fractions of rodent tumor cell lines, and normal rodent fetal liver and testis. These rodent genes should be a novel tool for studies on the biological roles of the SART-1 gene, and also in the construction of animal models of specific immuno-therapy using SART-1 gene products.  相似文献   
82.
The cytologic findings of the tumor cells characteristic of the stages of thymomas were investigated to assess the invasiveness of the tumors. Forty-six patients with thymoma who underwent extensive thymectomy without pre-operative corticosteroid therapy were included in this study. The histologic subtypes included 18 round/oval, 20 mixed, and 8 spindle type. The stages of thymoma classified according to Masaoka's clinicopathological classification included 16 stage I, 20 stage II, 6 stage III, 2 stage IVa, and 2 stage IVb, and myasthenia gravis was recognized in 5 patients. Cytologic findings were retrospectively analyzed in the Papanicolaou-stained stamp smears obtained from the cut surfaces of thymoma specimens. Morphometry of the epithelial tumor cells using Cosmozone-1A was performed to evaluate the validity of our cytologic categories. Compared with the cytologic findings of stage I or II thymomas, those of epithelial tumor cells in stage III or IV more frequently showed necrotic background (50.0%-stage III or IV vs 11.1%-stage I or II, p=0.006), large clusters of epithelial tumor cells (70.0% vs 36.1%, p=0.055), marked nuclear enlargement (90.0% vs 52.7%, p=0.033), marked anisokaryosis (100% vs 52.7%, p=0.006), marked nuclear polymorphism (40.0% vs 5.5%, p=0.004), hyperchromasia (50.0% vs 11.4%, p=0.007) and prominent nucleoli (50.0% vs 16.6%, p=0.028) whereas no significant correlation was observed between cytologic findings and tumor volume. Morphometric studies of thymoma tumor cells revealed that the nuclear size (mean values, 78.8 microm(3)-stage III or IV vs 58.2 microm(3)-stage I or II), the coefficient of variation of the nuclear size (0.326 vs 0.282), and the nuclear rotundity (0.849 vs 0.858) differed significantly between the two categories (p<0.05). Our findings demonstrated that there were significant differences between the cytologic findings of epithelial tumor cells of stage I or II thymomas and those of stage III or IV thymomas, and that the cytologic findings of thymoma tumor cells appear to be useful for distinguishing between non-invasive and invasive thymomas.  相似文献   
83.
84.
Aims: We aimed to determine the characteristics and vascular outcomes of stroke in renal transplant (RT) recipients and compare them with those in patients on hemodialysis (HD) and those with no renal replacement therapy (RRT). Methods: In this prospective observational study, 717 patients (mean age, 70.8 years; male, 60.5%) with acute ischemic stroke within one week of onset were consecutively enrolled and followed for one year. The patients were classified into three groups: (1) living donor RT recipients (n=27); (2) patients on maintenance HD before the index stroke (n=39); and (3) those with no history of RRT (n=651). The primary outcome was a composite of major adverse cardiovascular events (MACE). Results: Diabetic nephropathy was the most common reason for RRT in both RT and HD patients. RT patients were more likely to have embolic stroke of undetermined source (33.3%) than others, whereas HD patients more often had cardioembolism (51.3%). No difference was observed in the MACE risk between the patients in RT and non-RRT groups (annual rate, 11.3% vs. 13.1%; log-rankP=0.82; hazard ratio [95% confidence interval], 0.92 [0.29-2.98]). In contrast, HD patients had a greater risk of MACE than those with no RRT (annual rate, 28.2% vs. 13.1%; log-rankP=0.019; hazard ratio [95% confidence interval], 2.24 [1.16-4.3]). Conclusions: The underlying etiologies of stroke differed in RT and HD patients. The one-year risk of MACE for stroke patients who had received an RT was lower than that for patients undergoing HD and comparable with that of patients with no RRT.  相似文献   
85.
OBJECT: The effects of percutaneous transluminal angioplasty (PTA) and stent placement for stenosis of the petrous or cavernous portion of the internal carotid artery (ICA) were compared. METHODS: Twenty-four patients with symptomatic, greater than 60% stenosis of the petrous or cavernous portion of the ICA were treated using PTA or stent placement; 15 were treated with PTA and nine with stent insertion. Initial and follow-up results (> 3 months posttreatment) were compared in each group. Stenotic portions of the ICA were successfully opened in 13 of 15 patients in the PTA group, and in all nine patients in the stent-treated group. In one case in the PTA group stent delivery was attempted; however, the device could not pass through the vessel's tortuous curve, and PTA alone was performed in this case. Postoperatively, the mean stenotic ratio decreased from 72.1 to 29.6% in the PTA group, and from 75.6 to 2.2% in the stent-treated group. In four patients in the PTA group, stenoses greater than 50% were demonstrated on follow-up angiography performed at 3 to 6 months after PTA. In the stent-treated group, no restenosis was encountered, although in one case acute occlusion of the stent occurred; the device was recanalized with PTA and infusion of tissue plasminogen activator. This case was the only one of the 24 in which any neurological deficits related to the endovascular procedure occurred. Stent placement brought a greater gain in diameter than did PTA at the initial and late follow-up period; this gain was statistically significant. CONCLUSIONS: Stent placement is more effective than PTA for stenosis of the petrous or cavernous portion of the ICA from the viewpoint of initial and late gain in diameter.  相似文献   
86.
87.
AIM: To investigate and compare the efficacy of two machine-learning technologies with deep-learning (DL) and support vector machine (SVM) for the detection of branch retinal vein occlusion (BRVO) using ultrawide-field fundus images. METHODS: This study included 237 images from 236 patients with BRVO with a mean±standard deviation of age 66.3±10.6y and 229 images from 176 non-BRVO healthy subjects with a mean age of 64.9±9.4y. Training was conducted using a deep convolutional neural network using ultrawide-field fundus images to construct the DL model. The sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV) and area under the curve (AUC) were calculated to compare the diagnostic abilities of the DL and SVM models. RESULTS: For the DL model, the sensitivity, specificity, PPV, NPV and AUC for diagnosing BRVO was 94.0% (95%CI: 93.8%-98.8%), 97.0% (95%CI: 89.7%-96.4%), 96.5% (95%CI: 94.3%-98.7%), 93.2% (95%CI: 90.5%-96.0%) and 0.976 (95%CI: 0.960-0.993), respectively. In contrast, for the SVM model, these values were 80.5% (95%CI: 77.8%-87.9%), 84.3% (95%CI: 75.8%-86.1%), 83.5% (95%CI: 78.4%-88.6%), 75.2% (95%CI: 72.1%-78.3%) and 0.857 (95%CI: 0.811-0.903), respectively. The DL model outperformed the SVM model in all the aforementioned parameters (P<0.001). CONCLUSION: These results indicate that the combination of the DL model and ultrawide-field fundus ophthalmoscopy may distinguish between healthy and BRVO eyes with a high level of accuracy. The proposed combination may be used for automatically diagnosing BRVO in patients residing in remote areas lacking access to an ophthalmic medical center.  相似文献   
88.
Pure red cell aplasia (PRCA) associated with erythropoiesis-stimulating agents (ESAs), which were first reported in 1998, usually occurs with subcutaneous administration of epoetin alfa (Eprex). Improvements in ESA storage, handling, and administration methods have reduced the PRCA incidence. Continuous erythropoietin receptor activator (CERA) is a third-generation ESA that is rarely reported to induce PRCA. We herein report a case of CERA-induced PRCA presenting with positive anti-erythropoietin (EPO) and anti-CERA antibodies, which was successfully treated with prednisolone. Clinicians should be aware of the possibility of antibody-mediated PRCA induced by an ESA in CKD patients with anemia with reticulocytopenia and low serum EPO levels.  相似文献   
89.
We developed a sensitive, selective and accurate method based on liquid chromatography with tandem mass spectrometry (LC-MS/MS) to determine N-terminal thymosin-β peptides of Ac-SDKP and Ac-ADKP in human plasma samples. Quantification of Ac-SDKP and Ac-ADKP was performed using solid phase extraction (SPE) based on C(18), reversed phase LC separation, and stable isotope dilution electrospray ionization-MS/MS in multiple reaction-monitoring (MRM) mode. The Ac-SDKP-(13)C(6), (15)N(2) and Ac-ADKP-d(7) were synthesized for the internal standards. These MRM monitoring ions were m/z 488→129 (quantitative ion)/226 for Ac-SDKP, m/z 496→137 for Ac-SDKP-(13)C(6), (15)N(2), m/z 472→129 (quantitative ion)/226 for Ac-ADKP, and m/z 479→129 for Ac-ADKP-d(7), respectively. Lower limit of quantitation (LLOQ) of Ac-SDKP and Ac-ADKP was 0.1ng/mL in human plasma. Recovery values were ranged from 94.7% to 106.3% for inter- (RSD: 0.6-3.5%) and intra- (RSD: 0.4-4.9%) day assays. Plasma Ac-SDKP levels were significantly higher in hemodialyzed subjects treated with angiotensin-converting enzyme inhibitors of enalapril (27.3±24.6ng/mL, n=10) and trandolapril (12.3±16.9ng/mL, n=18) than healthy (0.4±0.2ng/mL, n=7) and hemodialyzed subjects (0.6±0.2ng/mL, n=34). This analytical method would be useful to measure N-terminal thymosin-β peptides in human plasma for the clinical study.  相似文献   
90.
Objectives: To clarify the clinical risk factors associated with poor neonatal outcomes due to umbilical cord prolapse (UCP).

Methods: A postal questionnaire survey was attempted in Japan. The clinical risk factors and managements associated with poor neonatal outcomes were analyzed in cases of UCP treated in Japan.

Results: A total of 267 cases of UCP (out of 2?037?460 total deliveries) were analyzed. The rates of intrauterine death, neonatal death and survival with disability were 3.4%, 5.6% and 7.1%, respectively. The multivariate regression analysis for these poor neonatal outcomes revealed that the significant risk factors included a prolapsed amniotic sac (adjusted odds ratio (aOR), 4.49), preterm labor (aOR, 2.99) and replacement of the prolapsed umbilical cord into the uterus (aOR, 2.87). However, UCP that occurred during labor (aOR, 0.28) and emergency cesarean section (aOR, 0.11) were associated with a reduction in the rates of poor outcomes. The interval between the diagnosis of UCP and delivery was significantly longer in the infants with a poor outcome than intact survival (median 30 versus 24?min, p?=?0.048).

Conclusion: An emergency cesarean section should be carried out immediately to ensure a better outcome for the infant.  相似文献   
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