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1.
Lobar torsion is reported as very rare but sometimes catastrophic complication if overlooked during the early postoperative period following a lobectomy, though it is totally preventable. In this novel technique, a piece of parietal pleural flap is harvested from the posterior wall of the chest using a hook diathermy while keeping its upper border as close to the apex as possible. Finally, distal end of the flap is secured to the upper edge of the lobe using a fine monofilament absorbable suture. This procedure not only protects the lobe from rotation but also maintains continuous expansion of the lung in the early postoperative period and may, therefore, be a good option to prevent such a serious complication in selected patients following a lobectomy.  相似文献   
2.
Erythropoietin exerts hematopoietic effects by stimulating proliferation of early erythroid precursors. Nonhematopoietic effects of erythropoietin have also been shown. It may act as a new angiogenic factor in wound healing. This study aimed to investigate the effect of systemic administration of recombinant human erythropoietin on wound healing in mice. Dorsal incisional wounds were performed in mice, which were then divided into two groups; a group treated for 7 days with recombinant human erythropoietin, and a control group. Sacrificing animals on day 7, the wound tissues were collected for analysis of wound breaking strength, malondialdehyde, a marker of lipid peroxidation, hydroxyproline, an index of reparative collagen deposition, reduced glutathione levels, and for histological evaluation. The immunohistochemical determination of vascular endothelial growth factor (VEGF) which is believed to be the most prevalent angiogenic factor throughout the skin repair process, was also studied. The treatment significantly increased wound breaking strength by decreasing malondialdehyde and increasing hydroxyproline levels on day 7 after wounding. No statistically meaningful change was observed in reduced glutathione content. VEGF was immunostained significantly more on wound tissue of treated animals compared to the control group. Recombinant human erythropoietin treatment may be effective in wound healing due to inhibition of lipid peroxidation, deposition of collagen, and VEGF expression in wound area.  相似文献   
3.
We investigated the effects of activated protein C resistance (APCR), Factor V Leiden (FVL) mutation, and high lipoprotein (a) levels in 32 young patients with branch retinal vein occlusion (BRVO) vs 30 controls. No difference between patients with BRVO and controls was found with regard to APCR, FVL mutation, or lipoprotein (a) levels. These factors do not seem important in the etiology of BRVO. The authors have stated that they do not have a significant financial interest or other relationship with any product manufacturer or provider of services discussed in this article. The authors also do not discuss the use of off-label products, which includes unlabeled, unapproved, or investigative products or devices.  相似文献   
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The radial nerve's course from the axillary region, branch patterns and the relation of the nerve to fixed anatomical landmarks in the arm region were studied in 27 embalmed intact cadavers. The radial nerve and its relation with the sulcus nervus radialis (SNR) was analyzed. The direct contact of the nerve with humerus in SNR was observed during the dissections. The following measurements were made: the total length of the humerus (the palpable uppermost point of the tuberculum majus and the lateral epicondyle); proximal safe zone (the tuberculum majus and the proximal beginning of the SNR); distal safe zone (the intercondylar axis and the middle of SNR); lateral safe zone (the lateral epicondyle and the distal end of SNR). In conclusion, it was aimed to correlate the osseus palpable landmarks of humerus with the course of the radial nerve for a safe surgery as the sulcus nervi radialis region is one of the main risky areas for the radial nerve palsies.  相似文献   
7.
Diffuse optical tomography with a priori anatomical information   总被引:1,自引:0,他引:1  
Diffuse optical tomography (DOT) poses a typical ill-posed inverse problem with a limited number of measurements and inherently low spatial resolution. In this paper, we propose a hierarchical Bayesian approach to improve spatial resolution and quantitative accuracy by using a priori information provided by a secondary high resolution anatomical imaging modality, such as magnetic resonance (MR) or x-ray. In such a dual imaging approach, while the correlation between optical and anatomical images may be high, it is not perfect. For example, a tumour may be present in the optical image, but may not be discernable in the anatomical image. The proposed hierarchical Bayesian approach allows incorporation of partial a priori knowledge about the noise and unknown optical image models, thereby capturing the function-anatomy correlation effectively. We present a computationally efficient iterative algorithm to simultaneously estimate the optical image and the unknown a priori model parameters. Extensive numerical simulations demonstrate that the proposed method avoids undesirable bias towards anatomical prior information and leads to significantly improved spatial resolution and quantitative accuracy.  相似文献   
8.
We aimed to evaluate the learning curve of the surgically standardised ‘Omega Sign’ anatomical endoscopic enucleation (AEEP) of the prostate surgery technique for junior surgeons. This study is a retrospective comparison of cases that underwent AEEP by a mentor surgeon and three junior surgeons who have completed their learning curve. A video-based laser enucleation of the prostate assessment tool (LEAT) composed of 8 steps of the technique was used to assess a senior surgeon and junior surgeons’ surgical compatibility and consistency. The surgeon who defined Omega Sign technique was determined as group 1, and cases by three junior surgeons were identified as group 2. The end points were to assess the reproducibility and repeatability and operative post-operative outcomes of the technique. 55 patients’ videos were rated by five experienced endourologists. There was no significant difference in LEAT scores between the groups among all steps. The most symmetry was found in the 1st and 3rd steps. Inter-rater consistency was also high for each step, with no statistically significant difference between the evaluators. The standardised anatomical ‘Omega Sign’ technique is reproducible for the junior surgeons. The operative steps can be performed with high consistency, and the functional and perioperative outcomes are comparable with the senior surgeon.  相似文献   
9.
Placental site trophoblastic tumor is a rare neoplasm that arises from intermediate trophoblasts and shows diversity of biological behaviors, resulting in the absence of consistency in treatment modalities. A case of placental site trophoblastic tumor that extended to the cervix, with primary manifestation of amenorrhea and yellow foul-smelling vaginal discharge, is presented. Total abdominal hysterectomy was performed initially, and serial measurements of human chorionic gonadotropin levels were obtained. She was admitted with metastases to brain and lung 1.5 years after surgery. Combination chemotherapy (etoposide-methotrexate-dactinomycin/cyclophosphamide-vincristine) and radiotherapy were administered. There was no significant response to chemoradiotherapy. Despite changing chemotherapy regimen, she is still alive with progressive disease.  相似文献   
10.
HYPOTHESIS: The goal of this experimental study was to investigate the specific effect of myringosclerosis on tympanograms in the tympanic membranes of myringotomized rats by using otomicroscopy, tympanometry, and histopathology. BACKGROUND: Myringosclerosis is a common sequela of ventilation tube treatment of otitis media with effusion. The condition involves the hyalinization and calcification of the collagen layer in certain areas of the tympanic membrane. Previous animal experiments suggest an intimate relationship between the formation of myringosclerosis and an increased oxygen concentration in the environment of the wound after myringotomy. The result of a myringotomy therefore is an increased production of free oxygen radicals, initiating irreversible tissue damage involving fibrosis, hyalin degeneration, and finally apoptosis as observed in myringosclerosis. We propose an experimental model specific for creating sclerotic plaques solely on the tympanic membrane and for performing tympanometric measurements on this pure myringosclerosis model without creating any abnormality in the middle ear to test in what proportion myringosclerosis contributes to decrease of amplitude in tympanograms. METHODS: To assess the normal tympanometric values of Wistar albino rats, the pressure and peak admittance of the left middle ears were measured using a semiquantitative computerized clinical admittance meter using a sound frequency of 226 Hz. Twelve animals were randomly selected for the myringotomy group and perforations in the left ears were created. All tympanic membrane perforations in this group had healed and closed prior to the otomicroscopic examination and no pathologic reaction was observed in the external ear canals of rats. Otomicroscopic and tympanometric measurements were carried out on Day 15 and the degree of myringosclerosis was noted before the animals were killed. Twelve specimens in the myringotomy group were histopathologically examined for the presence of myringosclerotic plaques. RESULTS: Under light microscopy, extensive sclerotic lesions were found in the tympanic membranes of the myringotomy group, and these sclerotic deposits were located in the lamina propria. The myringosclerosis occurred predominantly adjacent to the handle of the malleus, but also near the annular region. In all ears with myringosclerosis, the magnitude of the maximum admittance reduced to approximately 50% of the Day-0 values, and this reduction was statistically significant (Z=-3.061, p=0.002). CONCLUSION: The present findings in this study are consistent with the fact that the movement of the tympanic membrane is hampered by lesions of sclerotic material, resulting in a decrease of amplitude in tympanograms (such as Type As) without any effusion or inflammation in the middle ear.  相似文献   
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