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81.
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83.
Chordoid glioma is a rare benign neoplasm of uncertain histogenesis occurring in the third ventricle/ /suprasellar region. Recently, data have emerged suggesting that chordoid glioma is a variant of ependymoma related to a specialised ependyma of the subcommisural organ or the lamina terminalis area. In this study, we report clinicopathological and ultrastructural findings in two chordoid glioma cases. In case 1, a tumour (1.5 cm in diameter) in a 62-year-old man invaded the anterior-basal part of the third ventricle in the lamina terminalis region. In case 2, a large tumour in a 51-year-old woman occupied the whole third ventricle. The tumour attached to the medio-basal hypothalamic region. Histologically, both cases revealed a distinct chordoma-like pattern and glial immunophenotype of tumour cells. Under the electron microscope the tumour cells exhibited microvilli, intercellular lumina, intermediate type junctions and focal basal lamina formations. These findings were similar to those previously reported in the chordoid glioma cases. Moreover, the intracytoplasmic cilia and subplasmalemmal pinocytic vesicles or caveoles were observed. The study supports the view of ependymal derivation of chordoid glioma. Its relation to lamina terminalis or infundibular/median eminence area presumably reflecting tumour origin from the modified ependyma of circumventricular organs of the third ventricle is discussed.  相似文献   
84.
Tympanic sinus is located at the medial wall of the tympanic cavity. It's visualisation is difficult from most of approaches. Tympanic sinus is often filled with cholesteatoma in course of chronic otitis. Intraoperative assessment of tympanic sinus was performed in 29 patients with facial recess cholesteatoma, and in 20 patients with acoustic neuroma operated with translabyrinthine approach. In the group of patients with cholesteatoma four patients underwent canal wall up tympanoplasty with posterior tympanotomy, 25 underwent canal wall down tympanoplasty. Tympanic sinus was assessed during surgery with 30 degrees endoscope. In all cases depth of the sinus was measured with the use of calibrated hook. In 11 patients depth of the sinus exceeded 4 mm. In 6 among these features of bone destruction was found.  相似文献   
85.
Human brain ageing is associated with reductions in a variety of nicotinic receptors subtypes, whereas changes in age-related disorders including Alzheimer's disease or Parkinson's disease are more selective. In Alzheimer's disease, in the cortex there is a selective loss of the alpha4 (but not alpha3 or 7) subunit immunoreactivity and of nicotine or epibatidine binding but not alpha-bungarotoxin binding. Epibatidine binding is inversely correlated with clinical dementia ratings and with the level of Abeta1-42, but not related to plaque or tangle densities. In contrast, alpha-bungarotoxin binding is positively correlated with plaque densities in the entorhinal cortex. In human temporal cortex loss of acetylcholinesterase catalytic activity is positively correlated with decreased epibatidine binding and in a transgenic mouse model over expressing acetylcholinesterase, epibatidine binding is elevated. In Parkinson's disease, loss of striatal nicotine binding appears to occur early but is not associated with a loss of alpha4 subunit immunoreactivity. Tobacco use in normal elderly individuals is associated with increased alpha4 immunoreactivity in the cortex and lower densities of amyloid-beta plaques, and with greater numbers of dopaminergic neurons in the substantia nigra pars compacta. These findings indicate an early involvement of the alpha4 subunit in beta-amyloidosis but not in nigro-striatal dopaminergic degeneration.  相似文献   
86.
Objective: Pulmonary resections after pneumonectomy due to metastases or metachronous non-small cell lung cancer (NSCLC) are rare because of the high potential risk of the second procedure and uncertain long-term results. On the basis of our series (largest in Europe) we tried to assess the long-term survival of patients treated in stage IV NSCLC. Methods: Retrospective analysis was carried out on 18 patients treated at our department by pneumonectomy followed by additional resection in the years 1981-2002 (15 males and 3 females, 44-69 years, mean 57). Eleven pneumonectomies were performed on the right side and seven on the left. Twelve squamous cell carcinomas and six adenocarcinomas were diagnosed. All patients were staged postoperatively as IIB-IIIA (four were N2). Their WHO status ranged between 0 and 1. The second surgical procedure (16 wedge resections, 2 chest wall resections) was performed 4-106 months later (mean 26). The patients staged N2 were radiated postoperatively. Results: There were no early postoperative deaths. The morbidity rate after second surgery was comparable to that observed after ordinary wedge resection. Histology of the lesions removed during the second operation was the same as after pneumonectomy in all patients. The pulmonary function tests (PFT) results worsened significantly but still reached 56-63% of the predicted values. Sixteen resected tumors of the remaining lung were staged T1 (<3cm), 2 - T3 (<3cm but infiltration of the parietal pleura on an area of 2-4cm(2)). Three patients revealed N2 disease (they were all N0 after pneumonectomy). All patients were considered M1 after second surgery. WHO status after the second procedure remained the same in 8 patients (44%) and worsened in 10 patients (56%). The survival rates were as follows: 11 patients survived 2 years (61%) while 8 patients survived 5 years (44%). The majority of patients died due to lung cancer (70%) but all the rest (30%) due to circulatory or respiratory insufficiency. There was a significant difference (p<0.05) in 5-year survival for N0-N1 vs N2 status (63% vs 14% - 1 patient) and also regarding the time interval between surgeries: less than 12 months vs more than 12 months (0% vs 63%). Conclusions: Pulmonary resections performed after pneumonectomy due to NSCLC are rare procedures but with an acceptable perioperative risk. The second procedure should be limited to wedge resection. The prognosis is poor for patients with N2 status and for those treated by second surgery earlier than 12 months after the first procedure.  相似文献   
87.
BackgroundFlavonoids are dietary plant compounds suspected to reduce the incidence of chronic diseases in several regions of the world. Due to anti-allergic and anti-inflammatory activities, apigenin (4’,5,7,-trihydroxyflavone) is thought to interfere with crucial events in the pathomechanism of asthma. However, the effect of apigenin on TGF-β-induced fibroblast-to-myofibroblast transition (FMT) in human lung fibroblast populations, a key event in asthma progression, has not yet been addressed.MethodsPrimary human bronchial fibroblasts (HBFs) propagated from ex vivo bronchial biopsies derived from patients with diagnosed asthma and human embryonic lung IMR-90 fibroblasts were cultured in vitro and treated with TGF-β1 and apigenin. The myofibroblast fraction in fibroblast populations was evaluated by immunocytochemistry. Expression of α-smooth muscle actin (α-SMA) and tenascin C were assessed at the mRNA and protein level by real-time RT-PCR and immunoblotting, respectively. Additionally, proliferation and viability tests and time lapse-monitoring ofmovement of individual HBFs and IMR-90 cellswere evaluated.ResultsWe show that apigenin attenuates TGF-β1-induced FMT in cultures of HBFs, and the magnitude of this attenuation was found to be similar to that observed in the established cell line of lung IMR-90 fibroblasts. Notably, FMT inhibition was observed at low (~10 μM), non-cytotoxic and non-cytostatic apigenin concentrations and could be correlated with the inhibition of α-SMA and tenascin C expression in HBFs at the mRNA level.ConclusionsOur data are the first to demonstrate that apigenin inhibits the TGF-β1-induced expansion of hyper-contractile, α-smooth muscle actin – positive myofibroblasts within populations of HBFs derived from asthmatic patients. They also indicate the possible interference of apigenin with bronchial wall remodeling during the asthmatic process in vivo.  相似文献   
88.
The aim of the study was to assess the effect of three different types of anaesthesia on perioperative bleeding control and to analyse the mean arterial blood pressure and heart rate in patients undergoing endoscopic paranasal sinus surgery. Ninety patients (30 women and 60 men, aged 18–85 years) scheduled to undergo functional endoscopic sinus surgery in the years 2008–2010 were identified as candidates for inclusion in the study. Patients were randomly assigned to one of three groups (30 patients each) according to the type of general anaesthesia to be administered. Groups I and II both received inhalation anaesthesia (sevoflurane for sedation) and intravenous anaesthesia (fentanyl in group I, remifentanil in group II). Anaesthesia was delivered solely via intravenous route (TIVA) in group III, with propofol used for sedation and remifentanil for analgesia. Blood pressure and heart rate were monitored during surgery and post-surgically for 4 h. Mean anaesthesia duration in groups I, II and III was 108.7 ± 20.8, 112.6 ± 22.2 and 103.7 ± 17.5 min and the surgery duration was 71.3 ± 16.7, 78.8 ± 24.2 and 66.5 ± 15.5 min, respectively. Mean blood loss during surgery was 365.0 ± 176.2, 340.0 ± 150.5 and 225.0 ± 91.7 ml, with a mean blood loss rate of 5.1 ± 2.4, 4.5 ± 2.2 and 3.4 ± 1.1 ml/min in groups I, II and III, respectively. Technologically advanced control of the drug dose with the TIVA technique allows for better control of perioperative bleeding.  相似文献   
89.
Sonoelastography is a novel technique, useful in a noninvasive assessment of lesions in multiple organs. The aim of the study was to examine whether the combination of conventional ultrasonography (US) with sonoelastography might improve the reliability of parotid tumor evaluation. Fourty-three consecutive patients with parotid tumors were surgically treated at a single tertiary center at the Department of Otolaryngology, Head and Neck Surgery. The sample included 27 women and 16 men, aged 15–80 (the mean age = 54 years). The reference group constituted of 54 healthy volunteers. High resolution grayscale ultrasonography (US) was performed preoperatively using a 15 MHz linear array transducer. Elastograms (ES) were scored by the conventional Ueno 5-point scale from ES1 (blue-soft) to ES5 (the entire lesion and surrounding area shaded red-stiff). In addition, detailed stiffness values in kPa were collected. The group consisted of 33 patients with benign and 10 patients with malignant tumors. The mean stiffness value was 146.6 kPa in 10 malignant tumors (mostly ES4) and 88.7 kPa in 33 benign tumors (mostly ES2 and ES3). The differences in tissue stiffness between normal parotid parenchyma in the reference group and the mean value for all tumors in the examined group were statistically significant (p < 0.001), and so was the case with the differences between the benign and malignant tumors (p < 0.001). Low stiffness scores (ES1,2) were found in 2 malignant and 15 benign tumors while high scores (ES3,4) were found in 8 malignancies and 18 benign tumors. Sonoelastography overlapping elasticity to the grayscale images supports additional informations. Preferential selection of the lesions characterized by high stiffness (ES4) improves the differential diagnosis of parotid tumors but the large degree of uncertainty of this method should also be pointed out.  相似文献   
90.
Most prior morphometry data regarding the A2 segment of the anterior cerebral artery (ACA) have been based on cadaveric measurements. With newer imaging modalities, surgical techniques, and minimally invasive procedures, new standards for the anatomy of this vessel are necessary. A novel computer‐based data system was used to analyze the three‐dimensional (3D) morphometry of 230 A2 segments. In addition, tortuosity (TI) and deviation indices (DI) for this segment were calculated. The mean internal diameter of the A2 segment was 1.86 mm, and segments tended to be larger in men and on left sides. A2 segments were asymmetrical in 43%, and this was more common in women. Lengths tended to be greater on right sides and in men. Volumes were greater in men and increased with age, which was statistically significant. These gender differences were found to be statistically significant (P < 0.05), for both volume and diameter. TI was equal among sides, but DI was more often greater on right sides. The correlation coefficient ratio for length and DI was statistically significant. It is important to understand various 3D morphometrical differences particularly between genders. By constructing blood flow simulation models and during revascularization procedures, surgeons are able to gain a better understanding of each patient's vascular anatomy. These additional 3D data regarding the anatomy of the postcommunicating parts of the ACA may be useful to the neurosurgeon and interventional neuroradiologist. These data may assist with an earlier diagnosis of pathologies affecting the 3D morphology of the ACA. Clin. Anat. 23:759–769, 2010. © 2010 Wiley‐Liss, Inc.  相似文献   
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