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81.
82.
Primary malignant melanoma arising in the oesophagus is a rare condition with a dismal prognosis. The diagnosis is often made following surgical resection even though the endoscopic features may be pathognomonic. The classical treatment is oesophagectomy even though the advanced disease stage at the time of presentation and aggressive biological behaviour of the tumour usually results in a fatal outcome. We report the case of a male patient initially diagnosed with squamous oesophageal carcinoma and treated with conventional neo-adjuvant chemo-radiotherapy. Poor clinical and radiological response resulted in a review of the original histology confirming a diagnosis of primary malignant melanoma of the oesophagus. The subsequent alteration in management conferred the patient an improved quality of life. A short review of the literature on primary malignant melanoma of the oesophagus supplements this case report. 相似文献
83.
Canan Ceran Rauf Tu?rul Aksoy ?zlem Gülbahar Figen ?ztürk 《Clinics (S?o Paulo, Brazil)》2013,68(2):239-244
OBJECTIVES:
In addition to its roles in the stimulation of growth hormone secretion and the regulation of appetite and metabolism, ghrelin exerts immunomodulatory, anti-inflammatory and antioxidant actions in several organ systems. In this study, we investigated the effects of ghrelin on the healing of experimental colonic anastomoses.METHODS:
Wistar rats were randomly divided into two groups (n = 10 in each). A segment of colon was excised, and an end-to-end anastomosis was performed in the distal colon. The Ghrelin Group received 10 ng/kg/day IP ghrelin for seven days postoperatively, whereas the Control Group received an identical volume of saline. On the seventh postoperative day, the anastomotic bursting pressures and hydroxyproline levels were measured, and adhesion formation around the anastomoses was examined. Histopathological analyses were performed to evaluate inflammatory cell infiltration, fibroblast infiltration, collagen density and neovascularization.RESULTS:
In the Ghrelin Group, the bursting pressure and hydroxyproline levels were significantly higher than in the Control Group. The adhesion formation scores were lower in the Ghrelin Group than in the Control Group. Although the inflammatory cell infiltration was diminished in the Ghrelin Group, the degrees of fibroblast infiltration, collagen density and neovascularization were not significantly different between the groups.CONCLUSION:
Our results indicate that ghrelin improves the healing of colonic anastomoses in rats. 相似文献84.
Suleyman Celebi Durdane Aksoy Betul Cevik Abdullah Yildiz Semiha Kurt Ali Ihsan Dokucu 《Journal of pediatric surgery》2013
Background
A prospective study was performed to evaluate the effect of inguinal hernia repairs on the genitofemoral nerve (GFN), and to compare postoperative electrophysiologic changes in the GFN of patients who had undergone either open or laparoscopic surgery.Methods
Seventy patients with a mean age of 6.48 ± 3.49 were enrolled in the study. Either open or laparoscopic techniques were used to operate on the patients' inguinal hernias. In all cases, bilateral GFN motor responses were investigated electrophysiologically using surface electrodes on three occasions: preoperatively, in the first month, and third month postoperatively. t-Tests were used to compare changes in the GFN.Results
Preoperative mean latency of the GFN in all groups was found to be significantly prolonged on the hernia side, compared with the non-hernia side (P = 0.01). Although no difference was observed in the latency levels of the GFN on the operated side at the preoperative and early postoperative stages, GFN latency levels decreased significantly in the late postoperative period in the laparoscopic group (P < 0.05). In the late postoperative period, amplitudes of GFN motor responses were significantly higher in the laparoscopic group than the open repair group (0.91 ± 0.11 mV and 0.57 ± 0.053 mV, respectively; P < 0.05).Conclusion
Preoperative prolonged latency of GFN on the hernia side is likely to occur due to the pressure on the nerve caused by the hernia mass. By surgically removing the hernia mass, this buildup of pressure is prevented, decreasing the latency of the GFN. The significantly higher motor response amplitudes and decreased latency in the late postoperative stage for the laparoscopic group may be due to the fact that this technique is less invasive. 相似文献85.
Long-term anticoagulation in patients with metallic prosthetic valve disease is required according to current guidelines. We describe a patient with a functioning mitral mechanical valve without anticoagulation for 27 years. A 46-year-old man admitted to the emergency department with complains of palpitation. The patient had a mitral valve replacement because of severe mitral stenosis. He discontinued warfarin treatment 1 month after surgery because of the unavailability of this drug in Turkey. Transthoracic echocardiography revealed functioning metalic mitral valve with a mean gradient of 9 mm Hg. Fluoroscopy showed normal excursions of the mechanical mitral valve. Transesophageal echocardiography was performed and revealed fresh thrombus formation in the left atrial appendix. Admission international normalized ration (INR) level was 1.79. Due to the higher INR level and long-term survival, genetic analysis of warfarin polymorphism was performed. There was a homozygous mutation in the vitamin K epoxide reductase complex 1 (VKORC1) 1173C>T and 1639G>A genotypes. The possible explanations of long-term survival and baseline higher INR level were linked to the mutation in warfarin metabolism. We also briefly review the literature. 相似文献
86.
87.
88.
The effects of aging on the central nervous system steroid profiles and myelin basic protein in rats
Ciftci G Yarim GF Yarim M Karayigit MO Cenesiz S Nisbet C Gultiken ME 《Aging clinical and experimental research》2012,24(2):117-124
The aim of this study was to investigate the effects of aging on the central nervous system steroid and myelin basic protein (MBP) profiles. Forty-seven male Sprague-Dawley rats (newborn, 1, 6, 12 and 24-monthsold) were studied. Tissues were obtained from the cerebellum and parietal, frontal, temporal cortex of the central nervous system of the rats for steroid extraction. The estradiol, progesteron, testosterone and dehydroepiandrosterone (DHEA) levels were measured by Enzyme Linked Immunosorbent Assay (ELISA). The average levels of estradiol (pg/g), progesteron (ng/g), DHEA (ng/g) and testosterone (ng/g) in the brain tissues were respectively 24.29, 4.59, 0.27, 0.92 in the newborn-rats; 4.18 ± 1.10, 1.54 ± 0.30, 0.28 ± 0.01, 0.57 ± 0.10 in the 1 month-old-rats; 11.02 ± 1.10, 2.96 ± 0.30, 0.27 ± 0.01, 0.61 ± 0.10 in the 6 month-old-rats; 15.80 ± 1.10, 4.80 ± 0.30, 0.28 ± 0.10, 0.67 ± 0.10 in the 12 monthold- rats; 20.07 ± 1.10, 4.12 ± 0.30, 0.28 ± 0.01, 0.55±0.10 in the 24 month-old-rats. The myelin basic protein levels were determined by immunohistochemical staining and an elevation was observed in conjunction with the aging process. The results of the study indicate that the alterations in MBP, DHEA, progesterone, testosterone and estrodiol concentrations in the central nervous system of the rats during aging can be considered fundamental for future animal and human studies. 相似文献
89.
Maha B. Abd Elhaleem Ahmed A. Farghali Ahmed. A. G. El-Shahawy Fatma I. Abo El-Ela Zienab E. Eldine Rehab Khalid Mahmoud 《RSC advances》2020,10(22):13196
Zn–Al layered double hydroxides (LDHs) were synthesized by a chemical method, while polyvinyl alcohol (PVA) nanofibers were fabricated by an electrospinning approach; we also synthesized Zn–Al LDH/cefotaxime (cefotax), Zn–Al LDH@PVA, and Zn–Al LDH/cefotax@PVA (LCP). Characterizations were performed by X-ray diffraction, Fourier transform infrared spectroscopy, field emission scanning electron microscopy, high-resolution transmission electron microscopy, energy dispersive X-ray spectroscopy, Brunauer–Emmett–Teller analysis, thermogravimetric-differential thermal analysis techniques, dynamic light scattering, X ray-florescence, and carbon, hydrogen, and nitrogen (CHN) analyses. The adsorption isotherm of cefotax and its entrapment percentage, release, and kinetics were also investigated. The results confirmed the elemental constituents of the mentioned formulas, which exhibited different degrees of crystallinity and different morphologies. Besides, these formulas were tested in vitro as antimicrobial agents and applied in vivo against second-degree wound burns induced in rats'' skin. The adsorption of cefotax occurred chemically, and the experimental data were fitted with different isotherm models, where the Freundlich and Toth models gave the best fits. The entrapment percentage in LDH/cefotax was 77.41% and in LDH/cefotax@PVA, it was 67.83%. The sustained release of cefotax from LDH and LCP was attainable; the release percentages were 89.31% and 81.55% in up to 12 h, respectively. The release kinetics of cefotax from LDH fitted well with first-order kinetics, while that for LCP was parabolic. The formulas showed uneven antimicrobial effects against Gram-positive and Gram-negative bacteria; the best effect was exhibited by Zn–Al LDH/cefotax@PVA due to its sustained release. Finally, investigating the possibility of using these formulas in the clinical setting should be considered.This study succeeded to formulate, characterize, and investigate cefotax release and kinetics, and to compare cetofax with other known antibacterial agents. 相似文献
90.
Huseyin Oflaz Fatma Sen Sengul Kavak Bayrakli Ali Elitok Arif Oguzhan Cimen Ebru Golcuk 《Renal failure》2013,35(9):914-920
Background. Increased cardiovascular disease risk is very well known in nephrotic syndrome. Coronary flow reserve measurement by trans-thoracic echocardiography reflects coronary microvascular and endothelial function. However, diastolic filling abnormalities by echocardiography may indicate diastolic dysfunction. Our aim was to evaluate endothelial and diastolic functions by trans-thoracic echocardiography in nephrotic syndrome. Methods. Eighteen patients with nephrotic syndrome (five females, 34 ± 17 years) and 30 controls (10 females, 35 ± 10 years) were evaluated in this cross-sectional observational study. Age, weight, lipid profile, glucose, blood urea nitrogen, creatinine, serum albumin, total protein, C-reactive protein, erythrocyte sedimentation rate, blood pressures, 24-hour urine volume, and protein were recorded. Glomerular filtration rate was estimated by Cockcroft-Gault Formula. Doppler flow and other echocardiographic parameters were measured by Vivid 7 echocardiography. Results. Coronary flow reserve was significantly lower in patients than controls (p < 0.001) and was negatively correlated with proteinuria (p < 0. 001), creatinine levels (p?=?0.03), total cholesterol (p?=?0.02), C-reactive protein (p?=?0.02), and erythrocyte sedimentation rate (p?=?0.005). E/A ratio was significantly lower in patients than in controls (p?=?0.005). DT was significantly higher in patients than in controls (p?=?0.01) and isovolumic relaxation time was similar in both groups. Conclusion. Coronary flow reserve and left ventricular diastolic filling are significantly impaired in nephrotic syndrome. Proteinuria, serum creatinine, total cholesterol and inflammation may have all contributory effects on endothelial dysfunction. Early evaluation of patients with nephrotic syndrome should include coronary flow and diastolic function by echocardiography. 相似文献