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71.
72.
To obtain a new model of chronic portal hypertension in the rat, two classical methods to produce portal hypertension, partial portal vein ligation and the oral administration of thioacetamide (TAA), have been combined. Male Wistar rats were divided into four groups: 1 (control; n?=?10), 2 [triple partial portal vein ligation (TPVL); n?=?9], 3 (TAA; n?=?11), and 4 (TPVL plus TAA; n?=?9). After 3 months, portal pressure, types of portosystemic collateral circulation, laboratory hepatic function tests (aspartate aminotransferase, alanine aminotransferase, bilirubin, alkaline phosphatase, and gamma-glutamyl transpeptidase) and liver histology were studied. The animals belonging to group 2 (TPVL) developed extrahepatic portosystemic collateral circulation, associated with mesenteric venous vasculopathy without hepatic destructurization or portal hypertension. Animals from group 3 (TAA) developed cirrhosis and portal hypertension but not extrahepatic portosystemic collateral circulation, or mesenteric venous vasculopathy. Finally, the animals from group 4 (TPVL?+?TAA) developed cirrhosis, portal hypertension, portosystemic collateral circulation, and mesenteric venous vasculopathy. The association of TPVL and TAA can be used to obtain a model of chronic portal hypertension in the rat that includes all the alterations that patients with hepatic cirrhosis usually have. This could, therefore, prove to be a useful tool to study the pathophysiological mechanisms involved in these alterations.  相似文献   
73.
PURPOSE: Temporomandibular joint (TMJ) arthroscopy has been considered a safe surgical procedure in the treatment of TMJ derangement. However, it is not exempt from complications. This study evaluates the complications of arthroscopy in patients with internal derangement of TMJ. PATIENTS AND METHODS: Five hundred consecutive patients (670 joints) with TMJ derangement who underwent arthroscopy between 1995 and 2004 were retrospectively analyzed. All the patients were classified as II to V in the Wilkes classification. Lysis and lavage, electrocautery of the posterior ligament, injection of corticoids, injection of ethanolamine, myotomy of lateral pterygoid muscle attachments, myotomy and electrocautery, motor debridement, injection of sodium hyaluronate, and meniscal suture were performed in different patients. RESULTS: Complications were recognized during or immediately after the surgery. They were observed in 5 of 341 (1.26%) arthroscopies of the right TMJ and 4 of 329 (1.21%) arthroscopies of the left TMJ. A 1.34% complication rate was found in the whole series. No blood clots within the external auditory canal were observed. Bleeding within the superior TMJ space was observed in 57 cases (8.5%), 36 of them in the right TMJ and 21 in the left TMJ, but they were not considered as true complications. Lacerations of the external auditory canal were found in 2 cases (0.3%), with no cases of perforation of the tympanic membrane. Lesion of the auriculotemporal nerve was observed in a case. Paresia of the facial nerve was found in 4 cases (0.6%). Alteration of visual accuracy of the ipsilateral eye was also observed in a patient immediately after the surgery. CONCLUSION: Special care must be taken to reduce complications within the upper joint space by means of an adequate instrumentation and by paying attention to essential points of the arthroscopic technique.  相似文献   
74.
75.
The objective of this study was to determine the presence of different species of the genus Malassezia in the healthy external auditory canal of wild felids maintained in captivity. One hundred and thirty-two adult animals (264 samples of cerumen), 77 males (58.3%) and 55 females (41.7%), were studied: large felids (55 animals) - 26 lions (Panthera leo), 13 tigers (Panthera tigris), 6 leopards (Panthera pardus), 6 jaguars (Panthera onca), 2 cheetahs (Acinonyx jubatus), 2 pumas (Puma concolor); small felids (77 animals) - 29 tiger cats (Leopardus tigrinus), 19 jaguarundis (Herpailurus yagouaroundi), 10 margays (Leopardus wiedii), 9 pampas cats (Oncifelis colocolo), 6 geoffroy's cats (Oncifelis geoffroyi), and 4 servals (Leptailurus serval). Samples were obtained by the introduction of a sterile swab into the ear canal after cleaning the auricle with an alcohol-ether solution. The swabs were seeded onto Petri dishes containing modified Mycosel agar and sterile olive oil was added to the surface of the medium before specimen seeding. The plates were incubated at 35oC for two weeks. The isolates were analyzed regarding macro-and micromorphology and identified through catalase tests and growth on Tween 20, 40, 60 and 80. Malassezia spp. were isolated from 58 of the felids studied (43.9%) and from 102 samples of cerumen (38.6%). Malassezia sympodialis was isolated exclusively in large felids (33 animals-56.9%), and Malassezia pachydermatis exclusively in smaller varieties (25 animals - 43.1%). The incidence of fungi was higher in lions, with yeast being isolated in 25 of 26 animals (96.2%). Forty-eight strains (47.1%) were isolated from the right ear canal and 54 (52.9%) from the left. Although M. pachydermatis is the species considered a member of the microbiota of the mammalian external ear canal these results suggest that M. sympodialis participates in the microbiota of large felids.  相似文献   
76.

Background  

Acromioclavicular injuries are common in sports medicine. Surgical intervention is generally advocated for chronic instability of Rockwood grade III and more severe injuries. Various methods of coracoclavicular ligament reconstruction and augmentation have been described. The objective of this study is to compare the biomechanical properties of a novel palmaris-longus tendon reconstruction with those of the native AC+CC ligaments, the modified Weaver-Dunn reconstruction, the ACJ capsuloligamentous complex repair, screw and clavicle hook plate augmentation.  相似文献   
77.
Coronary angioplasty is known to mediate an inflammatory response. Recently, we have characterized the transient systemic inflammatory response after coronary stent implantation in patients with unstable angina by measuring different soluble protein markers. In the present study we have characterized the expression of various cellular activation markers in neutrophils, monocytes and lymphocytes from the same group of patients. Peripheral blood samples were taken before and 24 h, 48 h and 7 days after successful coronary stenting in 58 patients. Cell surface markers (CD11b/CD18 and CD38) were analyzed by flow cytometry to determine the activation of neutrophils, monocytes and T lymphocytes. We found that coronary angioplasty with stent implantation produces an increase in the cell surface expression of CD11b/CD18 in neutrophils and CD38 in monocytes, following a similar time-course with a peak after 24 h, returning to basal levels after 48 h and a second peak after 7 days. However, T lymphocytes were not found to be activated. These results suggest that coronary stent implantation induces a different pattern inducing soluble and cellular inflammation markers, and therefore, they should be taken into account in patients undergoing stent implantation to study clinical correlations.  相似文献   
78.
Intramedullary epidermoid cysts of the spinal cord are rare tumors, especially those not associated with spinal dysraphism. About 50 cases have been reported in the literature. Of these, only seven cases have had magnetic resonance imaging (MRI) studies. We report two cases of spinal intramedullary epidermoid cysts with MR imaging. Both were not associated with spina bifida. In one patient, the tumor was located at D4 vertebral level; while in the other, within the conus medullaris. The clinical features, MRI characteristics and surgical treatment of intramedullary epidermoid cyst are presented with relevant review of the literature.  相似文献   
79.
Gastrogastric fistula: a possible complication of Roux-en-Y gastric bypass.   总被引:4,自引:0,他引:4  
BACKGROUND: Gastrogastric fistula is a communication between the proximal gastric pouch and the distal gastric remnant, rarely described in the realm of bariatric procedures. The aim of this study was to review the existing literature about this topic and to demonstrate its laparoscopic treatment. METHODS: An extensive literature review found several articles reporting this complication. However, no citation was found describing the steps of the laparoscopic management of this situation. RESULTS: Gastrogastric fistula occurs in up to 6% of Roux-en-Y gastric bypasses. Two theories exist for fistula formation: (1) it is a technical complication derived from the incomplete division of the stomach during the creation of the pouch, and (2) it occurs after a staple-line failure, developing a leak with an abscess, which then drains into the distal stomach forming the fistula. Early symptoms include fever, tachycardia, and abdominal pain. Failure in weight loss is a late clinical sign observed in these patients. Diagnosis is based on radiologic study, upper endoscopy and computed tomography. When identified in the acute postoperative course, laparoscopic treatment is easy. Chronic fistulas are difficult to manage, and the laparoscopic approach is an alternative to open surgery. CONCLUSIONS: Gastrogastric fistula is a possible complication of Roux-en-Y gastric bypass and its laparoscopic treatment is feasible.  相似文献   
80.
Hypoxia is related to poor prognosis because it is associated to chemo-and radioresistance. During recent years the evolution of imaging methods like PET/CT and MRI has meant the appearance of new perspectives with direct implications in radiation therapy. We discuss previous experiences in staging, planning and in the follow-up process with these techniques for measuring tumour hypoxia.  相似文献   
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