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61.
The endometrium is a highly regenerative tissue that plays a crucial role in implantation. We examined the clonal constitution of glandular cells as well as the luminal epithelium of this unique tissue. Using collagenase-based digestion techniques with microscopic manipulation, we isolated individual human endometrial glands and examined their clonality using a polymerase chain reaction-based assay for nonrandom X chromosome inactivation with an X-linked androgen receptor gene. Most of the glands analyzed were composed of monoclonal populations of epithelial cells and one of the glands exhibited a loss of heterogeneity in the androgen receptor gene. In addition, adjacent glands within a 1-mm(2) area shared clonality, suggesting that clonality of the luminal epithelium is regionally defined. The clonality of endometrium was further confirmed in a study of female mice that harbor the green fluorescent protein gene on either the maternal or paternal X chromosome. Fluorescent microscopy of uterine sections revealed that individual endometrial glands consisted completely of either fluorescent or nonfluorescent cells and that the surface epithelium exhibited a clear boundary between these cell types. These findings suggest that single or multiple stem cells with uniform clonality exist on the bottom of each endometrial gland and genetic alterations occurring in such cells may play a critical role in endometrial carcinogenesis. The possible association between area-specific X inactivation of the endometrial surface and the endometrial receptivity of embryo implantation remains to be clarified.  相似文献   
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63.
ObjectiveWe sought to identify heterogeneous nuclear ribonucleoprotein A3 (HNRNPA3) expression in bladder cancer and its relationship to clinicopathological findings and prognosis.MethodsImmunohistochemical staining for HNRNPA3 was performed on 122 archived radical cystectomy specimens, with immunoreactivity being stratified on a 0 to 3 scale. The percentage of HNRNPA3 expressing tumor cells was calculated and multiplied by the staining score over an average of 5 areas to obtain a semiquantitative H-score (maximum value: 300). HNRNPA3 expression was categorized as high (≥80) or low (<80).ResultsThe patients’ median age was 70 years, and the median follow-up period was 39.4 months. High HNRNPA3 expression was significantly associated with lymph node metastasis (P= 0.014) and S100A8, S100A9 and uroplakin III expression (P= 0.028, 0.002, and 0.047, respectively). Log-rank tests indicated that high HNRNPA3 expression was significantly associated with disease progression and cancer-specific death (P= 0.013 and 0.006, respectively). In the Cox proportional hazards regression analysis, only lymph node metastasis was associated with disease progression and cancer-specific survival.ConclusionHNRNPA3 may be a new biomarker to predict biologically aggressive cancers and determine the appropriate treatment modality in patients after radical cystectomy.  相似文献   
64.
Pharyngeal cancer patients treated with intensity-modulated proton therapy (IMPT) using a model-based approach were retrospectively reviewed, and acute toxicities were analyzed. From June 2016 to March 2019, 15 pharyngeal (7 naso-, 5 oro- and 3 hypo-pharyngeal) cancer patients received IMPT with robust optimization. Simulation plans for IMPT and intensity-modulated X-ray therapy (IMXT) were generated before treatment. We also reviewed 127 pharyngeal cancer patients with IMXT in the same treatment period. In the simulation planning comparison, all of the normal-tissue complication probability values for dysphagia, dysgeusia, tube-feeding dependence and xerostomia were lower for IMPT than for IMXT in the 15 patients. After completing IMPT, 13 patients completed the evaluation, and 12 of these patients had a complete response. The proportions of patients who experienced grade 2 or worse acute toxicities in the IMPT and IMXT cohorts were 21.4 and 56.5% for dysphagia (P < 0.05), 46.7 and 76.3% for dysgeusia (P < 0.05), 73.3 and 62.8% for xerostomia (P = 0.43), 73.3 and 90.6% for mucositis (P = 0.08) and 66.7 and 76.4% for dermatitis (P = 0.42), respectively. Multivariate analysis revealed that IMPT was independently associated with a lower rate of grade 2 or worse dysphagia and dysgeusia. After propensity score matching, 12 pairs of IMPT and IMXT patients were selected. Dysphagia was also statistically lower in IMPT than in IMXT (P < 0.05). IMPT using a model-based approach may have clinical benefits for acute dysphagia.  相似文献   
65.
Temperature changes and their distribution induced by 13.56-MHz radiofrequency (RF) heating of agar phantom and porcine and rabbit liver were investigated. It was possible to produce selective local heating of approximately 50 degrees C in the RF field of 2 x 2 x 2 cm(3) of the pig or rabbit liver. Coagulation necrosis after heating became pronounced and the margin between the coagulated lesion and normal tissue became clearer with time. Within 1 week after RF heating at 50 degrees C for 20 min, the coagulated area was replaced selectively and totally by necrotic tissue.  相似文献   
66.
This article describes the measurement of the frontal and prefrontal lobe volumes on three dimensional (3-D) MRI in 13 children aged 5 months to 14 years and in 3 adults aged 27 to 39 years. The 3-D MRI data were acquired by the fast spoiled gradient recalled (SPGR) sequence using a 1.5 T MR imager. The frontal and prefrontal lobe volumes were measured by the volume measurement function of the Workstation. We confirmed that this technique to analyze segmental brain volumes achieved acceptable levels of reliability and accuracy. There was an increase in the frontal and prefrontal lobe volumes with advancing age, being rapid between 8 and 15 years of age. The prefrontal to frontal lobe volume ratio also increased gradually, with spurts between 8 and 15 years of age. This approach may be particularly useful for studies on patients with frontal and prefrontal lobe dysfunctions.  相似文献   
67.
68.
Electrical field stimulation (EFS) caused contraction of isolated tail arteries of rats. The EFS-induced contraction showed frequency-dependence and was entirely abolished by the sodium channel blocker tetrodotoxin (1 x 10(-7) M). The EFS-induced (at 20 Hz) contraction was reduced by about 60% in the presence of phentolamine (1 x 10(-6) M). Therefore, later experiments were carried out in the presence of phentolamine. Pyridoxal-phosphate-6-azophenyl-2',4'-disulphonic acid (PPADS) (1 x 10(-8)-1 x 10(-6) M) and basilen blue E-3G (3 x 10(-5)-5 x 10(-5) M), P2-receptor antagonists, significantly inhibited the contraction evoked by EFS. In addition, PPADS significantly inhibited the contractions induced by ATP (1 x 10(-4) M) and a selective P2x-receptor agonist, alpha,beta-methylene ATP (1 x 10(-6) M). In contrast, basilen blue E-3G did not inhibit alpha,beta-methylene ATP-induced contraction. The ecto-ATPase activator apyrase (5 and 10 U/ml) significantly reduced the EFS-induced contractions. These findings suggest that endogenous ATP released by EFS causes contractions of rat tail artery via both the P2x-receptors and P2y-receptors.  相似文献   
69.
(E)-2-deoxy-2-(fluoromethylene)cytidine (FMdC), one of the most potent inhibitors of ribonucleoside diphosphate reductase, was selected for clinical development because of its novel mechanisms of action, and strong antitumor activity against experimental tumor models. This study was designed to determine the toxicities, maximum-tolerated dose (MTD), and pharmacokinetic profile of FMdC. FMdC was given orally for 5 consecutive days every 3 or 4 weeks in patients with advanced solid tumors. The starting dose was 8 mg/m2/day. Pharmacokinetic studies were carried out on days 1 through 5 of the first cycle. Ten patients with non-small cell lung cancer received 15 courses of FMdC at doses which were de-escalated from 8 mg/m2/day to 2 mg/m2/day because of unexpected severe toxicities at the starting dose level. Neutropenia was the dose-limiting toxicity. Thrombocytopenia and anemia were mild. Flu-like symptoms and fever were the common non-hematologic toxicities. The MTD was 4 mg/m2/day, since four of six patients developed grade 3–4 neutropenia. At the 4 mg/m2/day dose level, the mean terminal half-life, maximum plasma concentration (Cmax), plasma clearance, and mean residence time on day 1 were 3.20 h, 15.8 ng/ml, 2.91 l/h/kg, and 4.03 h, respectively. The recommended dose for phase II studies with this schedule is also 4 mg/m2/day for 5 days. Further investigations are necessary to establish optimal dosing schedules and routes for the administration of FMdC.  相似文献   
70.
The purpose of the study was to show whether it was possible to produce alcoholic cardiomyopathy by short-term alcohol ingestion combined with an infinitesimally low endotoxin injection. Wistar rats were fed an alcoholic liquid diet according to the formula of Lieber and Decarli, and challenged with an injection ofE. coli lipopolysaccharide (LPS) endotoxin (1.0 g/g body weight per day for ten weeks). After ten weeks alcohol diet combined with LPS challenge, light microscopical examination showed changes commonly seen in alcoholic cardiomyopathy such as hypertrophy, oedema and disarray of myofibers. By electron microscopy, degeneration of mitochondria and degeneration of myocardial fibers were observed, the latter showing disturbance of the myofibrilla arrangement and interstitial fibrosis. Rats on an alcoholic liquid diet and rats challenged with a single identical doses of LPS did not show characteristic histological findings of alcoholic cardiomyopathy. These results suggest that short-term alcohol ingestion combined with an infinitesimally low endotoxin injection experimentally produces alcoholic cardiomyopathy, and may support the idea that endotoxin plays an important role in the aetiology of alcoholic cardiomyopathy.  相似文献   
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