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101.
Seyed Vahid Hosseini Hamid Reza Abbasi Hamid Rezvani Mohammad Vasei Mohammad Javad Ashraf 《Journal of investigative surgery》2013,26(2):148-153
Background: One of the most challenging problems in clinical surgery is management of an extensive duodenal injury. In its management, there are limitations in using jejunal serosal patch and other conventional methods in specific conditions. This study was performed to compare treatment of large duodenal defects by a gallbladder serosal patch and the gallbladder mucosal patch in a dog as an animal model. Methods: A duodenal defect (2 cm, about 50% of the total circumference) was created in the second portion of the duodenum in eight dogs. The animals were divided into two equal groups, with group 1 undergoing serosal patch repair and group 2 undergoing mucosal patch repair. The macroscopic and microscopic healing features of the gallbladder serosal and mucosal patch were compared. Results: None of the dogs died due to surgical complications. The whole grafted area was covered by neomucosa at the end of the third week in all animals with the gallbladder serosal patch (group 1). In this group, the scar was small; no significant narrowing of lumen was noted and serosal healing was uniformly complete. In histological examination, a complete coverage of the gallbladder serosal patch by neomucosa consisting of columnar epithelium with short villous formations was observed. In mucosal patch models (group 2), complete epitheliazation, mild fibrosis, and incomplete repair were visible. In histological examination, severe inflammation was noticed too. Conclusion: In patients with multiple trauma affecting upper gastrointestinal tracts, use of the gallbladder serosal patch method is easy and reliable. So it may be considered in the surgical management of large duodenal defects, which cannot be repaired by available conventional methods. 相似文献
102.
The presubiculum (PrS) plays critical roles in spatial information processing and memory consolidation and has also been implicated in temporal lobe epileptogenesis. Despite its involvement in these processes, a basic structure–function analysis of PrS cells remains far from complete. To this end, we performed whole‐cell recording and biocytin labeling of PrS neurons in layer (L)II and LIII to examine their electrophysiological and morphological properties. We characterized the cell types based on electrophysiological criteria, correlated their gross morphology, and classified them into distinct categories using unsupervised hierarchical cluster analysis. We identified seven distinct cell types: regular‐spiking (RS), irregular‐spiking (IR), initially bursting (IB), stuttering (Stu), single‐spiking (SS), fast‐adapting (FA), and late‐spiking (LS) cells, of which RS and IB cells were common to LII and LIII, LS cells were specific to LIII, and the remaining types were identified exclusively in LII. Recorded neurons were either pyramidal or nonpyramidal and, except for Stu cells, displayed spine‐rich dendrites. The RS, IB, and IR cells appeared to be projection neurons based on extension of their axons into LIII of the medial entorhinal area (MEA) and/or angular bundle. We conclude that LII and LIII of PrS are distinct in their neuronal populations and together constitute a more diverse population of neurons than previously suggested. PrS neurons serve as major drivers of circuits in superficial (LII–III) entorhinal cortex (ERC) and couple neighboring structures through robust afferentation, thereby substantiating the PrS's critical role in the parahippocampal region. J. Comp. Neurol. 521: 3116–3132, 2013. © 2013 Wiley Periodicals, Inc. 相似文献
103.
104.
Muddassir Mehmood Stephanie A. Ambach Michael D. Taylor John L. Jefferies Subha V. Raman Robin J. Taylor Hemant Sawani Jacob Mathew Wojciech Mazur Kan N. Hor Hussein R. Al-Khalidi 《Pediatric cardiology》2016,37(5):878-883
The relationship between pulmonary function and right ventricle (RV) in Duchenne muscular dystrophy (DMD) has not been evaluated. Using cardiac magnetic resonance (CMR), we describe the relationship of RV size and function with spirometry in a DMD cohort. Fifty-seven boys undergoing CMR and pulmonary function testing within 1 month at a single center (2013–2015) were enrolled. Comparisons of RV ejection fraction (RVEF) and end-diastolic volume index (RVEDVI) were made across categories of percent forced vital capacity (FVC%), and relationships were assessed. Mean age was 15.5 ± 3.5 years. Spirometry and CMR were performed within 3.9 ± 4.1 days. Median FVC% was 92.0 % (67.5–116.5 %). Twenty-three (40 %) patients had abnormal FVC% (<80 %) of which 13 (57 %) had mild (FVC% 60–79 %), 6 (26 %) had moderate (FVC% 40–59 %), and 4 (17 %) had severe (FVC <40 %) reductions. Mean RVEF was 58.3 ± 3.7 %. Patients with abnormal FVC% were older and had lower RVEF and RVEDVI. Both RVEF and RVEDVI were significantly associated with FVC% (r = 0.31, p = 0.02 and r = 0.39, p = 0.003, respectively). In a large DMD cohort, RVEF and RVEDVI were related to FVC%. Worsening respiratory status may guide monitoring of cardiac function in these patients. 相似文献
105.
Smoking cessation is associated with improved survival in oropharynx cancer treated by chemoradiation 下载免费PDF全文
Alexis J. Platek BSc Vijayvel Jayaprakash MBBS PhD Mihai Merzianu MD Mary E. Platek PhD David M. Cohan MD Wesley L. Hicks MD Jr. Sathiya P. Marimuthu MBBS Timothy B. Winslow MS Vishal Gupta MD Hassan Arshad MD Moni A. Kuriakose MD Shiva Dibaj MS James R. Marshall PhD Mary E. Reid PhD Graham W. Warren MD PhD Anurag K. Singh MD 《The Laryngoscope》2016,126(12):2733-2738
106.
Mohammad Golriz Saroa El Sakka Ali Majlesara Arman Edalatpour Mohammadreza Hafezi Nahid Rezaei Camelia Garoussi Jalal Arwin Arash Saffari Hanna Raisi Arezou Abbasi Arianeb Mehrabi 《Journal of gastrointestinal surgery》2016,20(3):587-594
Aim
Extended liver resection has increased during the last decades. However, hepatic hemodynamic changes after resection and the consequent complications like post hepatectomy liver failure are still a challenging issue. The aim of this study was to systematically evaluate the role of stepwise liver resection on hepatic hemodynamic changes.Methods
To evaluate this effect we performed 25, 50, and 75 % sequential liver resections in 10 pigs. Before and after each resection, the hepatic artery flow and portal vein flow in relation to the remnant liver volume (RLV) as well as hepatic vascular pressures were measured and compared between the groups.Results
Following sequential liver resection, the hepatic artery flow /100 g decreases and the portal vein flow increases up to 17 and 167 % following extended liver resection (75 %), respectively. Also, during stepwise liver resection, the portal vein pressure increases gradually up to 33 % following extended hepatectomy (75 %).Conclusion
Sequential decrease in the RLV decreases the hepatic artery flow /100 g and increases the portal vein flow /100 g and portal vein pressure. As the consequence, the liver goes under more poor-oxygenated blood supply and higher pressure. This may be one of the most important mechanisms of the post hepatectomy liver failure in case of extended liver resection.107.
Sayyed Ehtesham Hussain Naqvi Azam Haseen Mohammed Haneef Beg Eram Ali Mohammed Arshad 《Indian Journal of Thoracic and Cardiovascular Surgery》2016,32(2):152-155
The term aneurysm is derived from the Greek word aneurysma, meaning “a widening.” In current vascular surgery practice, an aneurysm is defined as a permanent localized dilatation of any vessel, having at least a 50 % increase in diameter compared with the expected normal diameter (Suggested standards for reporting on arterial aneurysms; Johnston et al., J Vasc Surg, 13: 452–458, 1991). Generally, this term is used for arteries as it is more common in them, but it can also be used for veins which are extremely rare presentation. In our case, a middle-aged female presented with complaints of swelling over the right mid-forearm flexor aspect with difficulty in flexing her wrist and paraesthesia over the right index finger and thumb. The patient was examined and diagnosed as a case of cephalic vein aneurysm compressing the median nerve. She underwent surgical resection of the involved segment of the cephalic vein. Venous aneurysm is a rare disorder and till date only few cases have been reported in English literature; however, its possibility should be kept when dealing with a subcutaneous mass in upper limb. 相似文献
108.
Photodynamic therapy with 3‐(1′‐hexyloxyethyl) pyropheophorbide‐a for early‐stage cancer of the larynx: Phase Ib study 下载免费PDF全文
109.
110.
Saeed SA Shad KF Simjee SU 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》2007,178(4):560-564
Thromboxane A2 (TXA2) formed in damaged brain tissue and after thromboembolism and subarachnoid haemorrhage is responsible for cerebral vasospasm.
In the present study, we examined the effect of human cerebrospinal fluid (CSF) on the production of thromboxane-A2 (TXA2) and 12-hydroxy-eicosatetraenoic acid (12-HETE) by human blood platelets. CSF was drawn by lumbar puncture from normal healthy
volunteers (n = 17) and samples judged to be normal after routine examination in the clinical laboratories and were used fresh. We found
that CSF inhibited the production of TXA2 and 12-HETE by blood platelets incubated with C14 labelled arachidonic acid (AA) in a concentration-related manner. Further biochemical analysis using proteolytic enzymes,
gel filtration and membrane partition chromatography showed that the inhibitory activity was peptidic in nature and associated
with a peptide of low molecular weight (1,400 Da). This study is the first to demonstrate that human CSF contains a dual inhibitor
of cyclooxygenase (COX) and lipoxygenase enzymes in CSF. 相似文献