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121.
122.
AP Mirra FA Justo JE Miziara CA Schneider N Trippe 《Canadian Metallurgical Quarterly》1995,41(4):277-283
OBJECTIVES: From 1947-1986 we reviewed a historical series of 1,900 cases of esophageal cancers registered at the A.C. Camargo Hospital, S?o Paulo, Brazil. Two hundred and thirty four cases were submitted to surgical resection. During these 4 decades the treatment philosophy of these tumors has changed. METHOD: Five different historical groups were identified and the results are presented. RESULTS: The first group (1947-60) consisted of 47 cases only submitted to surgical resection. The second group (1961-70) of 56 cases had pre and pos surgery radiotherapy in low doses and the reconstruction was made using subcutaneous colon. From 1971-75 the same approach was used except with high dose preoperative radiotherapy (31 cases). In the 4th group (1976-82) of 68 cases preoperative radiotherapy (high dose) and chemotherapy were used. In the last group (1983-86) composed of 32 cases the treatment was preoperative chemotherapy, surgical resection with gastric reconstruction followed with high doses radiotherapy in the surgical bed and chemotherapy. The only significant prognostic factors in the statistical analysis were tumor size and involvement peri-esophageal lymph nodes. CONCLUSION: A five year survival from 3.7% to 9.0% was obtained through the use of the fifth group treatment planning. 相似文献
123.
A highly specific anti-glutamate monoclonal antibody, mAb2D7, was used together with light and electron microscopy to elucidate the role played by the amino acid glutamate in the projection from the olfactory bulb to the piriform cortex in the rat. By light microscopy, glutamate-like immunoreactivity was observed in neuronal cell bodies and in the neuropil of the piriform cortex. Double labelling experiments which involved injections of wheat germ agglutinin-horse--radish peroxidase into the olfactory bulb and a post-embedding immunogold method for electron microscopy revealed anterogradely labelled terminals making asymmetric synaptic contacts on dendrites in the piriform cortex which contained high levels of glutamate as assessed by quantification. These results further support a role for glutamate as a neurotransmitter in the efferent pathway of the rat olfactory bulb. 相似文献
124.
JJ Hoorweg FJ Hilgers RB Keus FA Zoetmulder BM Loftus 《Canadian Metallurgical Quarterly》1998,24(5):452-455
BACKGROUND: This study evaluates the diagnosis and treatment of women with pathologic nipple discharge caused by ductal carcinoma in situ (DCIS). METHODS: Women with unilateral spontaneous bloody, serous, or brown nipple discharge who presented between January 1, 1988 and August 1, 1996 were identified by retrospective chart review. Women with nonspontaneous, physiologic discharge were excluded. RESULTS: Two hundred seventy-seven women with a mean age of 59.5 years (range, 24 to 88 years) underwent duct exploration and biopsy for pathologic discharge, with 43 (15.5%) found to have DCIS. The discharge was bloody in 29, clear in eight, and brown in six women. Seven of 12 (58%) women with an associated breast mass were found to have a microinvasive component with the DCIS. Discharge cytology showed malignant cells in only two of 12 (16%) women examined. A ductogram was performed on 20 women, with filling defects seen in 10, ectasia in 3, narrowing in 4, and normal ducts in 3. The DCIS included 17 (40%) specimens with cribriform pattern, 17 (40%) micropapillary, 8 (18%) comedo, and 2 (2%) solid. Twelve microinvasive cancers were found in combination with DCIS. After duct exploration, 37 (86%) patients were found to have extensive or multifocal DCIS to the margin, or both, with 32 (74%) patients requiring mastectomy to achieve free surgical margins. There was residual disease in 27 of 32 (84%) mastectomy specimens after initial biopsy. Breast conservation was possible in only 11 (26%) women. Forty of 43 (93%) are disease-free with a median follow-up of 37 months. CONCLUSION: Women presenting with pathologic nipple discharge require duct exploration regardless of cytologic or radiologic findings. When discharge is the result of DCIS, extensiveness of disease in relation to central location and intraductal spread may preclude breast conservation in as many as 27 of 43 (63%) cases. 相似文献
125.
Isolated resting platelets are able to limit neutrophil activation and then can control the tissue-damaging potential of activated neutrophils. In the present study, platelet-neutrophil interactions have been evaluated in 10 uremic patients; the blood samples have been collected before the hemodialysis session. Twelve normal subjects served as controls. Platelets and neutrophils have been isolated and recombined in an autologous ex vivo system. Anion superoxide production and chemiluminescence (which is related to hypochlorous acid production) have been evaluated after stimulation with N-formyl-methionyl-leucyl-phenylalanine. Coincubation of platelets from normal subjects with autologous neutrophils led to a dose-dependent inhibition of both superoxide anion generation induced by N-formyl-methionyl-leucyl-phenylalanine and chemiluminescence. Instead, platelets from uremic patients have not affected superoxide anion production by autologous neutrophils. The chemiluminescence was reduced by coincubation with autologous platelets only at the highest platelet-neutrophil ratio (100:1). In conclusion, the modulation exerted by platelets towards neutrophil activation can be impaired in chronic uremia. Therefore, the tissue-damaging potential of circulating neutrophils, due to toxicity by superoxide anion and hypochlorous acid, may be increased. 相似文献
126.
HA Kurvers MJ Jacobs RJ Beuk FA van den Wildenberg PJ Kitslaar DW Slaaf RS Reneman 《Canadian Metallurgical Quarterly》1994,87(6):663-669
1. To investigate the nature of sympathetic dysfunction in the pathogenesis of reflex sympathetic dystrophy, the microcirculatory vasoconstrictive responses to dependency were investigated in the skin of the hand of 76 reflex sympathetic dystrophy patients with unilateral disease by means of laser Doppler flowmetry (in perfusion units) and capillary microscopy. The patients were divided into three stages according to their perception of skin temperature (stage I in the case of a stationary warmth sensation, stage II in the case of an intermittent warmth and cold sensation, and stage III in the case of a stationary cold sensation). The vasoconstrictive responses were induced by lowering of the affected hand. 2. As compared to controls, the mainly sympathetically mediated vasoconstrictive response at thermoregulatory level of the skin microcirculation, as measured by laser Doppler flowmetry, was attenuated at stage I (1.82 versus 1.41, P < 0.05), stage II (1.82 versus 1.09, P < 0.0001) and stage III (1.82 versus 1.14, P < 0.01), suggesting the involvement of sympathetic denervation at all stages of the reflex sympathetic dystrophy syndrome. This sympathetic denervation may also account for the observed increase in thermoregulatory skin blood flow at stage I as compared to controls (152 versus 81, P < 0.01). 3. Since sympathetic denervation has been reported to cause increased sensitivity of vascular structures to catecholamines, the decrease in thermoregulatory skin blood flow at stages II (54 versus 81, P < 0.05) and III (31 versus 81, P < 0.05), both as compared to controls, may result from hypersensitivity to catecholamines of skin microvessels. 4. The sympathetically independent vasoconstrictive response at the nutritive level of skin microcirculation, as measured by capillary microscopy, was impaired only at stage III as compared to controls (1.04 versus 2.06, P < 0.05). This divergence in microvascular reactivity upon dependency of the nutritive and thermoregulatory subsystems also supports the hypothesis of sympathetic dysfunction.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
127.
JA Oliveira Filho AC Silva E Lira Filho B Luna Filho SH Covre FA Lauro MA Danucalov WA Leite S Tuffik JL Andrade AA de Paola E Martinez Filho 《Canadian Metallurgical Quarterly》1997,69(6):385-388
Nineteen children with congenital upper alimentary tract malformation were studied prospectively at the Department of Paediatrics, University College Hospital (UCH), Ibadan, over a period of 12 months. There were 20 cases, grouped into six types comprising congenital hypertrophic pyloric stenosis, seven; cleft lip and/or cleft palate, five; oesophagal atresia with or without tracheo-oesophageal fistula, four; jejunal atresia two and a case each of achalasia and annular pancreas. One patient had oesophageal atresia and congenital hypertrophic pyloric stenosis. The mortality rate was 31.51% (six out of nineteen). Low mortality was recorded in cases of cleft lip and/or palate, while mortalities of over 70% were recorded among cases of jejunal atresia, and oesophageal atresia with or without tracheo-oesophageal fistul. The common causes of death were milk feed aspiration (28.6%-two cases), purulent peritonitis (14.3%-one case), and probable septicaemia (14.3%-one case). The cause of death in two cases could not be determined. 相似文献
128.
R Plate MJ Plaum P Pintar CG Jans T de Boer FA Dijcks G Ruigt JS Andrews 《Canadian Metallurgical Quarterly》1998,6(9):1404-1420
A series of 1,6-dihydro-5-(4H)-pyrimidinone oxime derivatives I was synthesized (Scheme 1, Tables 1 and 2) and tested for muscarinic activity (Table 3) in receptor binding assays using [3H]-oxotremorine-M (Oxo-M) and [3H]-pirenzepine (Pz) as ligands. Potential muscarinic agonistic or antagonistic properties of the compounds were determined using binding studies that measured their potencies to inhibit the binding of Oxo-M and Pz. Preferential inhibition of Oxo-M binding was used as an indicator for potential muscarinic agonistic properties; this potential was confirmed in functional studies on isolated organs. The series produced a wide range of active compounds with differing degrees of selectivity in M1, M2, and M3 functional models. Several compounds that have mixed agonist/antagonist profiles were able to reduce cholinergic-related cognitive impairments in models of mnemonic function. Substitutions (I, e.g. R2 or R3 = Me) at the 1,6-dihydro-5-(4H)pyrimidine ring disrupted binding and efficacy, whereas systematic variation of the oximes substituent R1 resulted in various degrees of potency and selectivity dependent on the nature of the substitution. 相似文献
129.
FA Atik GJ Lopes Filho Mde M Linhares J Seda Neto NS Mansur 《Canadian Metallurgical Quarterly》1998,116(4):1781-1783
The authors report a case of a 25 year old Brazilian man with a history of crampy abdominal pain in the left iliac fossa for 2 weeks, abdominal distention, mucous diarrhea and anorexia. The patient presented signs of hemodynamic instability and a hard mass palpated in the left iliac fossa presented peritoneal irritation. At laparotomy, fecal peritonitis and a punched-out perforation of the midsigmoid colon were found. A left hemicolectomy was performed with terminal colostomy. Specimen examination revealed a thickened rectosigmoid wall, narrow lumen and multiple mucosal polyps. Microscopically, chronic granulomatous colitis with Schistosoma mansoni eggs confirmed the etiology. To the authors' knowledge, this is the first case of obstruction complicated with perforation due to mansoni schistosomiasis reported in the literature. 相似文献
130.
The N-methyl-D-aspartate R1 (NMDA R1), NMDA R2A, and NMDA R2C subunits were expressed transiently in double or triple combinations in human embryonic kidney (HEK) 293 cells. The biochemical and pharmacological properties of the cloned receptors were compared with those of adult mouse forebrain and cerebellum. Under conditions established for maximal expression, cotransfection of the NMDA R1 and R2C subunits yielded a protein detected immunologically with a molecular size of 780,000-850,000 daltons. No cell death was observed in the transfected cells, and the KD for [3H]MK801 binding to the NMDA R1/R2C receptor was 346 +/- 158 nM. This was in contrast to a value of KD = 22 +/- 9 nM found for native cerebellar receptors. Co-transfection with NMDA R1/R2A/R2C subunits with a DNA ratio, 1:3:3, resulted in the expression of a protein with a size similar to the NMDA R1/R2C combination, but the affinity of [3H]MK801 was now 22 +/- 5 nM, and the percentage cell death post-transfection was 89 +/- 17%. Immunoprecipitation assays of detergent-solubilized transfected cells with NMDA R1 subunit-specific antibodies co-precipitated the NMDA R2A and NMDA R2C subunits in 1/2A and 1/2C transfections, respectively. Similarly, immunoprecipitations with either NMDA R1 or NMDA R2C subunit-specific antibodies co-precipitated the NMDA R2A subunit in the R1/2A/2C triple transfections. These results show that the three NMDA receptor subunit types can co-assemble following their co-expression in mammalian cells with a pharmacological profile that is similar to that found for adult cerebellar NMDA receptors. 相似文献