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81.
While thyroglossal duct cysts are a frequent cause of cervical masses, carcinomas arising in thyroglossal duct remnants are rare. In this paper the Authors report a new case, which occurred in a young woman. The diagnosis of carcinomas in thyroglossal duct cysts almost always comes as a surprise upon pathologic examination. The type of neoplasia most frequently described in Literature is that of the papillary carcinoma (82%). Other types of carcinomas are also reported in Literature: mixed follicular-papillary carcinomas (9 cases), squamous cell carcinomas (10 cases) and follicular carcinomas (3 cases). There are different theories regarding the origin of and therapy for these malignancies. In the sixties some Authors thought that these carcinomas were metastases of thyroid carcinomas. Now, following demonstration of normal thyroid tissue occurrence in the wall of thyroglossal duct cysts, it is almost universally accepted that a carcinoma may arise from thyroglossal remnants. The foci of cancer found in the thyroid reported only infrequently in Literature are a result of the plurifocality of papillary carcinoma. The Authors suggest that the Sistrunk procedure is an adequate, sufficient treatment if the carcinoma is limited to the cyst's walls. They also recommend postoperative administration of substitution therapy of thyroid hormones. Indications for thyroidectomy are then discussed. 相似文献
82.
P Pfeiffer E Nex? SM Bentzen PP Clausen K Andersen C Rose 《Canadian Metallurgical Quarterly》1998,78(1):96-99
PURPOSE: Cyclosporine-A (CSA) combined with corticosteroid therapy was administered to 12 patients with severe Beh?et's uveitis who were resistant to colchicine or cytotoxic therapy. METHODS: Previous colchicine or cytotoxic therapies were tapered off one month before CSA therapy. All patients were started on an initial oral dose of 5 mg/kg/day of CSA. After the first three months, the CSA dose was reduced to a maintenance dose according to the intraocular inflammatory response. RESULTS: The average follow-up period was 20 (12-36) months. Visual acuity remained the same in 12 (%54.5) and improved in 8 (%36.4) eyes. There was a decrease in the frequency (p<0.01) and severity (p<0.01) of ocular attacks and in the maintenance steroid dose (p<0.01) when compared with conventional therapy. The frequent side effects were paraesthesia-hyperesthesia, fatigue, nausea, hirsutism and dose-related nephrotoxicity in one patient. CONCLUSION: The results of the study suggest that low dose CSA combined with low dose corticosteroid may be an effective therapeutic alternative in the treatment of severe refractory Beh?et's uveitis. 相似文献
83.
JL Pereira T Gómez-Cia M Garrido J Parejo E Jódar P Serrano H Romero J Fraile A Franco PP García-Luna 《Canadian Metallurgical Quarterly》1996,11(5):274-278
The objective of this study was to evaluate the effect of early enteral nutrition on the incidence of the septic syndrome as well as its tolerance, in patients with severe burns. We retrospectively studied 64 patients older than 15 years of age, with a greater than 20% burned body surface area. They were divided into 2 groups as a function of the time elapsed between the beginning of Enteral Nutrition and the time of the burning: 23 patients were given Enteral Nutrition within 24 hours after the burn, and in 41 patients the enteral nutrition was started later than 24 hours after sustaining the thermal injury. Both groups were similar with respect to age, sex, percentage of 2nd and 3rd degree burns, incidence of inhalation, and deaths. All patients received the Enteral Nutrition through a nasogastric tube, with administration of a polymeric, hyperprotein and hypocaloric formula through a continuous infusion pump. In our study we saw a reduction of the incidence of the septic syndrome in the patients who received early enteral Nutrition (26%; 6 patients of a total of 23), with respect to those who did non receive early Enteral Nutrition (54%; 22 patients of a total of 41), with a statistical significance of p > 0.05. There were no differences between both groups with respect to the digestive tolerance to Enteral Nutrition. From our study we can deduce that early Enteral Nutrition reduces the incidence of septic complications, without this increasing the digestive intolerance to the same. 相似文献
84.
AJ Sansum IP Chessell GA Hicks DJ Trezise PP Humphrey 《Canadian Metallurgical Quarterly》1998,37(7):875-885
Extracellular and whole-cell patch clamp recordings were used to study the excitatory responses elicited by purine nucleotides in pontine slices of the rat brain containing the locus coeruleus (LC). The P2 purinoceptor agonists, alphabeta-methyleneadenosine 5'-triphosphate (alphabetameATP) and adenosine 5'-O-(2-thiodiphosphate) (ADPalphabetaS), and a novel purinoceptor agonist, alphabeta-methyleneadenosine 5'-diphosphate (alphabetameADP), elicited concentration-dependent increases in the spontaneous firing rate over the concentration range (1-300 microM). On vagus nerve or dorsal root preparations alphabetameADP (100 microM) had no agonist activity. In the presence of both alphabetameATP (300 microM), ADPbetaS (300 microM) elicited a further and significant increase in the firing rate of the LC neurones, whilst neither alphabetameATP nor alphabetameADP (300 microM) elicited a further response. The P2 purinoceptor antagonists, suramin (100 microM) and pyridoxalphosphate-6-azophenyl-2',4'-disulphonic acid (PPADS; 30 microM), markedly attenuated responses to all three agonists. Whole-cell recording of membrane current showed that, at - 60 mV, alphabetameATP and alphabetameADP (both 100 microM) elicited inward currents of a similar magnitude, whilst the inward currents elicited by a lower concentration of ADPbetaS (30 microM) were larger and faded in the presence of this agonist. In the presence of tetrodotoxin and a combination of other neurotransmission blockers, both alphabetameATP and alphabetameADP still produced inward currents. Based on the known selectivity of the agonists used in this study, there appear to be two distinct P2 purinoceptor types present on neurones in the LC, which correspond to the P2X and P2Y types. The responses elicited by alphabetameADP appear to be mediated through a putative P2X purinoceptor, although further work is required to determine which P2X receptor subtype(s) are involved. 相似文献
85.
Retroperitoneal space is an exceptional location of extrauterine pregnancy (four cases have been previously reported). The authors report a case of retroperitoneal ectopic pregnancy. Pathogenesis is discussed. 相似文献
86.
NA Foudraine GJ Weverling T van Gool MT Roos F de Wolf PP Koopmans PJ van den Broek PL Meenhorst R van Leeuwen JM Lange P Reiss 《Canadian Metallurgical Quarterly》1998,12(1):35-41
The functional projection of the medial perforant path (MPP) to different CA3 subfields was studied in urethan-anesthetized rats using current source density analysis. MPP stimulation resulted in an early-latency (presumed monosynaptic) sink with onset of 2-3 ms at the distal apical dendritic layer of CA3 (stratum lacunosum molecule) and a long-latency (presumed disynaptic, >7 ms) sink at stratum lucidum and radiatum of CA3. The population spike (onset 5. 3-6.1 ms), a sink at CA3 pyramidal cell layer, was observed 67% of the time (12 of 18 rats) in CA3a, 44% (8 of 18) in CA3b and 58% (7 of 12 rats) in CA3c following MPP stimulation. Population spike was not observed during presumed disynaptic excitation of CA3. Both early-latency sink (excitatory postsynaptic potential) and population spike in CA3 revealed robust paired-pulse facilitation (PPF). In contrast, little PPF was found for the MPP-evoked excitatory sink at the middle molecular layer of the dentate gyrus. The data suggested that the entorhinal cortex provides a strong monosynaptic excitation of different subfields of CA3. A direct entorhinal to CA3 input bypasses the dentate gyrus and may play a role in normal hippocampal signal processing and neural plasticity. 相似文献
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