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951.
Parotidectomy may be associated with a significant depression in the retromandibular region and a significant incidence of gustatory sweating (Frey's syndrome). Superiorly and inferiorly based sternocleidomastoid flaps and posterior plication of the superficial musculoaponeurotic system were evaluated for their ability to ameliorate both consequences. Sixteen patients with sternocleidomastoid flaps and 16 patients with superficial musculoaponeurotic system plication were compared to a control group of 104 patients. The incidence of Frey's syndrome was 47.1% in the control group, 12.5% (P = 0.025) in the sternocleidomastoid flap group, and 0% (P = 0.005) in the superficial musculoaponeurotic system plication group. The surgical techniques are described. The prevalence of Frey's syndrome is discussed with respect to age, sex, radiation therapy, and the type of parotidectomy performed. The indications and contraindications of the three surgical techniques are described. 相似文献
952.
Cellular mechanism of the conduction abnormalities induced by serum from anti-Ro/SSA-positive patients in rabbit hearts. 总被引:1,自引:1,他引:0
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S Garcia J H Nascimento E Bonfa R Levy S F Oliveira A V Tavares A C de Carvalho 《The Journal of clinical investigation》1994,93(2):718-724
In this study, IgG fractions from sera of SLE patients with anti-Ro/SSA or anti-Ro/SSA and anti-La/SSB activity were tested in Langendorff preparations of adult rabbit hearts, aiming to reproduce the cardiac manifestations observed in neonatal lupus in an experimental model. The hearts were perfused with normal Tyrode's solution for 30 min, followed by perfusion with Tyrode's containing 0.3 mg/ml of anti-Ro/SSA- (or anti-Ro/La-) positive IgG (nine sera), anti-ribonucleoprotein (RNP)-positive IgG (five sera), or IgG fractions from normal donors (five sera). In one third of the experiments done with anti-Ro/La-positive IgG, heart block was observed. With the remaining fractions, a decrease in heart rate of 17.1% was observed, but normal sinus rhythm was maintained. The IgG fractions with anti-RNP activity (five experiments) and from normal sera (six experiments) reduced heart rates by 12.9 and 3.3%, respectively, but heart block was not observed. To further characterize the cellular mechanisms involved in the conduction disturbances observed in the whole rabbit hearts, we conducted experiments with ventricular myocytes isolated from young rabbit hearts, studied by whole cell patch-clamp technique. In these experiments, the slow inward currents were analyzed during the superfusion of the cell with normal Tyrode's solution and 5 min after superfusion with Tyrode's solution containing 0.3 mg/ml of anti-Ro/SSA- (or anti-Ro/La-) positive IgG (five sera), anti-RNP-positive IgG (three sera), or IgG from normal donors (four sera). Resting and action potential amplitudes were not affected by any of the sera used. The anti-Ro/SSA IgG fraction induced a mean reduction in the peak slow inward current of 31.6%. IgG fractions with anti-RNP activity reduced slow inward current by 4.4%, whereas IgG fractions from normal donors increased this current by 3.3%. IgG-free fractions from sera of patients with anti-Ro/SSA activity did not alter the peak slow inward current. These results show, for the first time, that the presence of anti-Ro/SSA or anti-Ro/SSA and anti-La/SSB antibody activity in IgG fractions from lupus patients' sera can induce cardiac conduction disorders similar to those observed in neonatal lupus. 相似文献
953.
We examined ultrastructural correlates of synaptic plasticity in the hippocampus of young (3 months) vs aged (30 months) Wistar rats and established the effects of the calcium antagonist nimodipine in animals chronically treated from 24 to 30 months. The effects of nimodipine was studied since this compound improves hippocampal neuronal physiology and enhances cognitive function during aging. In the supragranular layer of the dentate gyrus we found a 24% decrease in synaptic density (Nv) in aged animals, while synaptic size (S) was not significantly altered. After nimodipine treatment Nv in aged rats was not significantly different from young adults, thus being significantly increased compared to age-matched controls. The size of synapses was not significantly altered after nimodipine administration. Total synaptic surface area (Sv) in nimodipine-treated animals was significantly increased compared to aged controls, however, Sv remained significantly lower than in young adults. These data indicate that chronic administration of nimodipine enables granular cells in the dentate gyrus to maintain its number of synaptic contacts during the aging process. Furthermore, the presented influence of nimodipine on synaptic plasticity processes may underlie previously reported improved cognitive functioning of aged animals treated similarly with nimodipine. 相似文献
954.
955.
Intracranial alveolar echinococcosis: CT and MRI 总被引:1,自引:0,他引:1
A. H. Bensaid J. L. Dietemann M. M. Filippi de la Palavesa A. Klinkert B. Kastler A. Gangi G. Jacquet F. Cattin 《Neuroradiology》1994,36(4):289-291
Intracranial alveolar echinococcosis is uncommon. We report a patient with right frontal lobe and palpebral lesions secondary to a primary hepatic focus with secondary lesion in the lung. The intracranial and palpebral cystic masses were totally removed and both proved to be alveolar hydatid cysts. An unusual feature in this case is CT and MRI demonstration of dural and bony extension. 相似文献
956.
Is colonoscopic screening appropriate in asymptomatic patients with family history of colon cancer? 总被引:1,自引:0,他引:1
Martin A. Luchtefeld M.D. Dale Syverson M.D. Mark Solfelt M.D. John M. MacKeigan M.D. Randall Krystosek M.D. James Waller M.D. Jeffrey W. Milsom M.D. 《Diseases of the colon and rectum》1991,34(9):763-768
Colonoscopy has been advocated by some investigators as the most appropriate means of screening asymptomatic patients with a positive family history of colorectal cancer. However, results of such screening have been widely disparate. The purpose of this study was to evaluate the yield of colonoscopy in a cohort of completely asymptomatic individuals with one or two first-degree relatives with a history of colorectal cancer and to compare this yield with that of colonoscopy in a group of patients with apparent anal bleeding. Patients with possible genetic disorders, such as familial polyposis, were excluded. A total of 160 asymptomatic patients and a comparison group of 137 patients with nonacute anorectal bleeding underwent colonoscopy. Colonoscopy was completed in 143 of the 160 study patients (89 percent) and in all of the comparison patients and did not result in any complications. Twenty-two adenomas were found in 17 study patients (10.6 percent); 16 of the 22 adenomas were less than 1 cm in size. In the comparison group, eight adenomas were identified (5.8 percent of patients). No cancers were identified. The difference in polyp frequency between groups was not significant. The relatively low yield of colorectal neoplasms discovered at colonoscopy in this study may in part be due to the small sample size or to the strict criteria used to define these asymptomatic patients but does not lend strong support to the notion that colonoscopy is an appropriate first step in screening the asymptomatic patient with one or two first-degree relatives with colon cancer. 相似文献
957.
958.
959.
Primary pregnancy in the liver. A case report 总被引:1,自引:0,他引:1
A de A Barbosa Júnior L A de Freitas M A Mota 《Pathology, research and practice》1991,187(2-3):329-31; discussion 332-3
A case of intra-hepatic pregnancy is reported. The patient was 32 years old and presented with an acute intra-abdominal hemorrhage. At surgery a spongy 3 x 2 x 1.5 cm mass was removed from the right liver lobe. Microscopically, well developed chorionic villi appeared invading the liver tissue. The patient had a relatively uneventful recovery. 相似文献
960.
Magruder C. Donaldson MD Michael Belkin MD Anthony D. Whittemore MD John A. Mannick MD Janina A. Longtine MD David M. Dorfman MD PhD 《Journal of vascular surgery》1997,25(6):1054-1060
Purpose: The prevalence of activated protein C resistance (APCR) and associated thrombotic morbidity among patients who undergo arterial reconstruction were investigated.Methods: Preoperative assays for functional APCR and factor V (Leiden) mutation were performed on 262 patients who underwent arterial reconstructions that consisted of cerebrovascular surgery (109), aortic or iliofemoral procedures (76), or infrainguinal bypass procedures (77). Patients were monitored for thrombotic complications during the postoperative period.Results: Depending on the stringency of the definition used, functional APCR was detected in 10.6% to 22.0% of patients tested. Factor V (Leiden) was found in 5.3% of patients. Thrombotic morbidity consisting of myocardial infarction, cerebrovascular event, or graft thrombosis occurred in 9.9% of patients, who were followed-up for a mean of 4.8 months. No significant overall correlations were found between APCR and thrombotic morbidity. Subgroup analysis revealed significant associations between functional APCR and total early postoperative thrombotic complications and early graft failure, and between factor V (Leiden) and early cerebrovascular events and late graft thrombosis (p < 0.03).Conclusions: Functional APCR is somewhat more prevalent among general vascular surgical patients than in the general population, but factor V (Leiden) is no more prevalent. APCR is not a prominent cause of thrombotic morbidity in contemporary vascular surgery. Nonetheless, it is a sufficiently important potential contributor to morbidity among some subgroups to warrant selective testing and directed therapy pending further study. (J Vasc Surg 1997;25:1054-60.) 相似文献