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51.
HYPOTHESIS: This study reports on the use of the double posterior labyrinthotomy surgical technique and a custom-designed electrode to ensure better positioning of stimulating electrodes within the common cavity and thus demonstrate suitable outcomes in patients. BACKGROUND: Cochlear implantation has proven beneficial for numerous children with congenital malformations of the inner ear. Several studies show good auditory perception outcomes in children with common cavity. However, there have been risks involved with surgical techniques used in the actual implantation. These include possible aberrant facial nerve and the strong potential for a cerebrospinal fluid gusher. Improved surgical techniques and electrode design could allow for better electrode contact and avoid electrode placement in the internal auditory meatus. METHOD: The double posterior labyrinthotomy technique was carried out in three cases using a custom made MED-EL COMBI 40+ electrode. RESULTS: Surgery was carried out with no complications and is no more technically demanding than other standard surgical approaches. The speech processor program remains stable over time, and auditory perception results are similar to those obtained from children with no cochlear abnormalities. CONCLUSION: These results demonstrate the success of the double posterior labyrinthotomy approach with modified cochlear implant, and this could be recommended as the procedure of choice in children presenting to an implant team with a common cavity.  相似文献   
52.
Intracranial administration of -arginine causes a reduction of the water intake induced by water deprivation or by intracerebroventricular (i.c.v.) injection of angiotensin II (angiotensin II), through the release of nitric oxide (NO) in the central nervous system. We studied the effects of i.c.v. angiotensin II (120 ng/rat) in association with i.c.v. -arginine (2.5–10 μg/rat) on blood pressure. We also studied the effects of both peripheral and central angiotensin II injection (1.5–6 mg kg−1 i.p. and 30–120 ng rat−1 i.c.v., respectively) on NO synthase activity in the cortex, diencephalon and brainstem, after water deprivation (24 h), conditions producing activation of the renin-angiotensin system. -arginine dose dependently antagonized the increase in blood pressure induced by i.c.v. angiotensin II (P<0.001). Peripheral administration of angiotensin II produced a dose-dependent reduction of NO synthase activity in the brainstem and cortex (P<0.001), but not in the diencephalon. Water deprivation produced similar effects on brain NO synthase activity. Angiotensin II i.c.v. injection caused NO synthase activity reduction in all brain regions studied (P<0.001). Our findings suggest that NO and angiotensin II could play opposite roles in brain regulation of blood pressure and drinking behaviour.  相似文献   
53.
There is experimental evidence of an interaction between the angiotensin system and lipid metabolism. The aim of this study was to evaluate whether a block of the angiotensin system achieved both by ACE inhibition and angiotensin II-AT1 receptor blockade could affect the plasma lipid profile and, if so, what relationship exists between these possible changes and glucose metabolism and blood pressure. In 50 patients with type 2 diabetes and hypertension, treated with diabetes drugs and enalapril, we evaluated the glycemic and lipid profile together with the HOMA insulin-resistance index, blood pressure and microalbuminuria at baseline and 3 months after the addition of valsartan. At the second evaluation, blood pressure was reduced as expected, whereas the glycemic profile, the HOMA index, and the body mass index were unchanged. Total cholesterol, LDL-c, and apoprotein B were reduced during combination therapy (P = 0.003, P = 0.001, and P = 0.004, respectively), plasma HDL-c was slightly though significantly increased (P = 0.024), whereas apoprotein A and triglyceride levels did not change. After adjustment for the insulin resistance index and for blood pressure, the reduction of LDL-c and apoprotein B and the increase in HDL-c remained significant. The variation in lipid profile was not related to the changes in blood pressure. Moreover, the addition of valsartan to enalapril was associated with a reduction in microalbuminuria, which remained significant after adjustment for LDL-c or blood pressure changes. Thus, the greater degree of renin-angiotensin system blockade or specific pharmacodynamic effects of valsartan could account for the changes in plasma lipid profile observed in this study.  相似文献   
54.
55.
Familial Mediterranean fever is an autosomal recessive disorder characterized by transient attacks of fever and polyserositis with substantial risk of developing amyloidotic nephropathy over time. We report an Italian child with familial Mediterranean fever presenting with hematuria during attacks in whom kidney biopsy documented the presence of mesangial IgA deposits and the absence of amyloidosis. Kidney biopsy should be performed in patients showing microscopic or gross hematuria during attacks of familial Mediterranean fever in order to gain additional epidemiological data about specific features of renal involvement and to allow adequate treatment.  相似文献   
56.
The aim of this retrospective study was to evaluate the use of digital videofluorography in the preoperative and postoperative management of esophageal achalasia surgical treatment. From 1990 to 2004, 25 patients with achalasia, diagnosed by digital videofluorography and confirmed by motility studies and endoscopy, underwent surgery. All patients underwent digital videofluorography at 1, 6 and 12 months in order to evaluate the completeness of the myotomy and the efficacy of the antireflux procedures. At postoperative videofluorography esophageal transit time was decreased in all patients (100%); esophageal motor activity was unchanged in 23 (92%), and modified in two patients (8%) with onset of peristaltic-like motor activity; 8 patients (35%) presented decreased preoperative dilatation; all patients had a WST negative for post-myotomy reflux. On the basis of our experience and the advantages of the procedure we suggest videofluorography as a first-approach diagnostic examination useful for surgical indications and postoperative follow-up in achalasic patients.  相似文献   
57.
58.
The aim of the study was to report our experience with the use of radiology in functional disorders of the cricopharyngeal muscle and their surgical therapy using digital cineradiology. Five-hundred and seventy dysphagic patients underwent dynamic study of the oral and pharyngeal phases of swallowing (Videofluoroscopic Swallowing Study, VFSS). A motor disorder of the cricopharyngeal muscle was diagnosed by videofluorography in 19 patients: the disorder was mild in 8, moderate in 7 and severe in 4. Two of these underwent cricopharyngeal myotomy, with an improvement in their dysphagia and swallowing mechanisms. VFSS provides a morphological and functional view of the aero-digestive tracts: this is essential in the diagnosis of cricopharyngeal dysfunction and is capable of revealing the related laryngeal penetration and tracheal aspiration. VFSS must always include an oesophageal phase study because of the known clinical and physico-pathological correlations between the gastro-oesophageal junction and the upper oesophageal sphincter. On the basis of our experience we believe that VFSS could be used as a primary investigation, followed by motility studies, and that it may be a useful complementary procedure both in the diagnosis of pharyngo-oesophageal junction motor disorders and with a view to surgical indications.  相似文献   
59.
1. The aim of this study was to investigate the effect of GW274150, a novel, potent and selective inhibitor of inducible nitric oxide synthase (iNOS) activity in a model of lung injury induced by carrageenan administration in the rats. 2. Injection of carrageenan into the pleural cavity of rats elicited an acute inflammatory response characterized by: fluid accumulation in the pleural cavity which contained a large number of polymorphonuclear cells (PMNs) as well as an infiltration of PMNs in lung tissues and subsequent lipid peroxidation, and increased production of nitrite/nitrate (NO(x)), tumour necrosis factor alpha (TNF-alpha) and interleukin-1beta (IL-1beta). 3. All parameters of inflammation were attenuated in a dose-dependent manner by GW274150 (2.5, 5 and 10 mg x kg(-1) injected i.p. 5 min before carrageenan). 4. Carrageenan induced an upregulation of the intracellular adhesion molecules-1 (ICAM-1), as well as nitrotyrosine and poly (ADP-ribose) (PAR) as determined by immunohistochemical analysis of lung tissues. 5. The degree of staining for the ICAM-1, nitrotyrosine and PAR was reduced by GW274150. These results clearly confirm that NO from iNOS plays a role in the development of the inflammatory response by altering key components of the inflammatory cascade. 6. GW274150 may offer a novel therapeutic approach for the management of various inflammatory diseases where NO and related radicals have been postulated to play a role.  相似文献   
60.
BACKGROUND: Splenic marginal zone lymphoma (SMZL) is a well defined pathologic entity. However, questions regarding the bone marrow infiltration rate, the minimal diagnostic data set, and therapy remain unanswered. METHODS: Clinical-pathologic features and outcomes of 57 consecutive patients who had splenomegaly with no clinically significant lymphadenomegaly and who were diagnosed with SMZL with or without (+/-) villous lymphocytes (VL) were reviewed. RESULTS: SMVL +/- VL occurred mostly in elderly males (median age, 62 years +/- 10 years; male-to-female ratio, (1.85). Anemia was recorded in 49% of patients, and 30% of patients had moderate thrombocytopenia. Leukocytosis and leukopenia were found in 33% and 14% of patients, respectively, and typical VL were found in 84% of patients. Serology for hepatitis C virus infection was positive in 16% of patients, and a small monoclonal component was detected in 36% of patients. The bone marrow was infiltrated with an intrasinusoidal component in all patients. Thirteen patients were monitored using a watch-and-see policy, and they remained alive 1-5 years after diagnosis. Overall, 21 patients (36%) underwent splenectomy; and, in all patients, the diagnosis of SMZL was confirmed histologically in the surgical specimens. Twenty-five patients received single-agent therapy, which included either alkylators or pentostatine, and they achieved an overall response rate (ORR) of 65% and 87%, respectively: Polychemotherapy was administered to 6 patients (ORR, 83%). The median survival for all patients in the series was not reached, and it is expected that 70% of patients will be alive at 5 years. CONCLUSIONS: Up to 20% of patients who had SMZL +/- VL could be monitored using a watch-and-wait policy. The bone marrow intrasinusoidal infiltration pattern may be a valuable diagnostic hallmark, thus obviating diagnostic splenectomy. The issues regarding prognostic stratification and the best therapeutic strategy need to be addressed in properly designed, prospective trials.  相似文献   
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