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11.
Mentally retarded adolescents and MA-matched nonretarded children participated in three experiments designed to examine differences in language-processing efficiency. A compressed speech technique was used in Experiments 1 and 2. Experiment 3 relied on a sentence-picture verification procedure. Our results suggest that retarded and nonretarded individuals differ in the speed with which they are able to execute the semantic-analytic processes but not necessarily the phonological encoding processes that are involved in auditory language comprehension. In addition, the data suggest a possible group difference in the quality of the semantic representation encoded during sentence processing. 相似文献
12.
Enrique Cases Luis Seijo Carlos Disdier María José Lorenzo Rosa Cordovilla Francisca Sanchis Marimar Lacunza Gregoria Sevillano Fátima Benito-Sendín 《Archivos de bronconeumologia》2009,45(12):591-596
IntroductionTo analyse the effectiveness and safety of the indwelling pleural catheter in the management of recurrent malignant pleural effusion.Patients and methodsA prospective multicentre study was performed in 63 consecutive outpatients from four Spanish hospitals. A total of 43 men and 20 women were included, with a median age of 67 years. In seven of the cases treatment with pleurodesis had failed; in five other cases their lung was trapped; in another five cases after repeat therapeutic thoracocentesis, and the rest of them as a preference choice to pleurodesis. All patients had an indwelling pleural catheter inserted (PleurX®, Denver Biomedical).ResultsMost of patients (94.5%) reported an improvement in their respiratory symptoms (cough and dyspnoea) and their ability to function independently. Average length of the catheterisation was 45 days (6-222). Average amount of drained pleural effusion was 75 ml, with a frequency of drainage of between 3 and 4 times per week and once fortnightly. Spontaneous pleurodesis was achieved following 34.9% of procedures. No complications occurred during the insertion of the catheter. The post-catheterisation complications were empyema (3 cases), chest pain (2 cases), and tumour metastasis (3 cases).ConclusionsThe use of an indwelling pleural catheter is an effective palliative treatment in the outpatient management for patients suffering malignant pleural effusion. It is also a simple treatment that can be easily applied, does not require hospitalisation and can be easily managed by the patient at home, with a low rate of complications. 相似文献
13.
14.
José Abal Arca Isaura Parente Lamelas Raquel Almazán Ortega José Blanco Pérez María Elena Toubes Navarro Pedro Marcos Velázquez 《Archivos de bronconeumologia》2009,45(10):502-507
Background and objectiveTo analyse frequency, characteristics and patient survival with lung cancer (LC) and Common Obstructive Pulmonary Disease (COPD), comparing them with patients that do not have COPD.Material and methodsA retrospective study, of patients diagnosed by means of cytohistology. Survival was estimated by the Kaplan-Meier method. Statistical analysis was carried out using SPSS 15.0.ResultsA total of 996 patients were diagnosed, 39.8% with COPD. Mean age70±9.19 years. GOLD stages: I 18.2%, II 53.6%, III 24%, IV 4.2%. The histological types: squamous cell carcinoma 48.2%, adenocarcinoma 22%, and small cell carcinoma 22.5%. Survival was longer in the COPD group.ConclusionsLC and COPD are combined in 39.8%. Squamous cell type is more frequent and survival was longer in the COPD group. 相似文献
15.
Plasma levels and vascular effects of vasopressin in patients undergoing coronary artery bypass grafting. 总被引:1,自引:0,他引:1
Susana Novella Ana Cristina Martínez Rosa María Pagán Medardo Hernández Albino García-Sacristán Angel González-Pinto José María González-Santos Sara Benedito 《European journal of cardio-thoracic surgery》2007,32(1):69-76
OBJECTIVE: Recent studies have suggested that endogenous vasopressin (AVP) acts as a spasmogen during coronary artery bypass grafting (CABG). Given that AVP could induce vasospasm in the grafted vessel, we assessed the release of this peptide during and after CABG, and explored ways of counteracting its contractile effect on the internal mammary artery (IMA). METHODS: Plasma levels of AVP were determined by radioimmunoassay in 16 patients before, during and after CABG. Using isometric force recording techniques, we also investigated the mechanisms involved in the contractile effect of AVP in ring preparations of IMA specimens taken from 95 patients. RESULTS: Plasma AVP levels peaked after the start of cardiopulmonary bypass (CPB) and correlated well with serum osmolality (Pearson's r=0.9490; P<0.0001; n=16). An inverse correlation was observed between plasma AVP levels recorded at this stage and the maximal contraction induced in vitro by AVP in vascular rings from the same patients (Pearson's r=-0.6968; P<0.01; n=16). No change in the AVP response was produced by endothelium removal, exposure to the NO precursor (3 x 10(-4)M L-arginine), inhibition of nitric oxide (NO) synthase (3 x 10(-5) M L-NAME) or soluble guanylate cyclase (3 x 10(-6) M 1H-[1,2,4]oxadiazol [4,3,-alpha]quinoxalin-1-one (ODQ)), removal of the superoxide anion (100 U/ml superoxide dismutase (SOD) plus 1200 U/ml catalase) or hydroxyl radical (10(-4) M deferoxamine), or specific alpha1 - (10(-6) M prazosin) or endothelin (10(-5) M bosentan) receptor antagonism. In contrast, adenylate cyclase activation (3 x 10(-8) M forskolin) reduced the contractile response to AVP, while prostanoid synthesis (3 x 10(-6) M indomethacin) inhibition and blockade of Ca2+ -activated potassium channels (KCa) (10(-3) M tetraethylammonium (TEA)) enhanced AVP contraction. Age, gender and smoking also modified the AVP response. CONCLUSION: Our findings suggest a role for AVP as a modulator of vascular tone in human IMA. The effect of AVP is dependent on prostanoids and Ca2+ -activated K+ channels, so its dysfunction in pathophysiological cardiovascular processes could mean that AVP, among other factors, produces vasospasm in IMA grafts. 相似文献
16.
Jose M. Fernández-Cebrián Peter Vorwald Kuborn Mar Pardo de Lama Alfonso Sanjuanbenito Dehesa Manuel Nevado Santos Pedro A. Pacheco Martínez Beatriz Fernández-Escudero 《Clinical & translational oncology》2005,7(3):101-109
Colorectal cancer is one of the best studied of all malignant diseases interms of genetics and/or molecular prognostic factors. These factors, and relationships with prognosis, may have important implications especially in the design of surgical and adjuvant chemo-radiotherapy options. However, the true prognostic significance of all known factors has yet to be realised. We have reviewed the literature with specific focus on the role of molecular markers involved in prognosis and the prediction of response to adjuvant treatment. 相似文献
17.
Carmen Guillén Ponce María Pilar Garrido López María José Molina Garrido Gema Muñoz Molina Alfredo Carrato 《Clinical & translational oncology》2007,9(1):53-55
Pituitary metastases of solid tumours are infrequent, specially as a first manifestation. When they happen, they are usually
due to breast or lung cancer and are asymptomatic or produce diabetes insipidus. It is very strange that they produce hormonal
deficiency.
We present a case report of a bronchogenic adenocarcinoma in a 65-year-old man which began with panhypopituitarism, diabetes
insipidus and visual alterations. Magnetic resonance imaging revealed a large sellar mass, with clivus infiltration and invading
the right cavernous sinus. The biopsy result was adenocarcinoma metastases from lung cancer. 相似文献
18.
José Ignacio Bilbao Mercedes Arias Jesús María Longo Pedro Luis Alejandre María Teresa Betés Arlette María Elizalde 《Cardiovascular and interventional radiology》1997,20(2):149-153
Percutaneous embolization of large portosystemic collaterals was performed in three patients following placement of a transjugular
intrahepatic portosystemic shunt in order to improve hepatopetal portal flow. Improved hepatic portal perfusion was achieved
in these cases, thereby theoretically reducing the risk of chronic hepatic encephalopathy. 相似文献
19.
Carlos Sala M.D. Eduardo García-Granero M.D. Ph.D. María J. Molina M.D. Jose V. García M.D. Salvador Lledo M.D. Ph.D. 《Diseases of the colon and rectum》1997,40(8):958-961
PURPOSE: Epidural anesthesia is believed to benefit colorectal anastomotic blood flow because of the sympathetic blockade it produces. Our purpose is to measure with tonometry the effect of epidural anesthesia on colorectal anastomotic oxygenation. PATIENTS AND METHODS: Fifteen patients operated on for rectal cancer (radical anterior resection) were monitored postoperatively using tonometers placed in the stomach (celiac trunk), transverse colon (superior mesenteric artery), and the anastomotic area during the operation. An epidural catheter was placed at L1-2, and on the first postoperative day, 8 ml of bupivacaine (0.25 percent) was administered. The anesthetic effect extended up to T-4. Intramucosal pH (pHi) at the three locations was measured before, during, and after the epidural blockade. RESULTS: Gastric and transverse colon pHi increased during the epidural blockade from 7.35±0.01 to 7.41±0.01 and from 7.34±0.02 to 7.40±0.02, respectively. The anastomotic pHi decreased from 7.3±0.02 to 7.24±0.03 under the epidural and increased up to 7.34±0.02 after withdrawal of the effect on the following day. All pHi variations were statistically significant (P<0.05, paired Student'st-test and Wilcoxon's test), because it was the comparison between gastric and transverse colon pHi with the anastomotic pHi during the epidural (P<0.05, one-way analysis of variance and Kruskal-Wallis tests). None of the patients developed anastomotic or other complications. CONCLUSIONS: Epidural anesthesia with bupivacaine causes a significant decrease in the oxygenation-perfusion state of colorectal anastomosis in comparison with the increase in other areas of the digestive tract. Further studies need to be done to see if other epidural anesthetic-analgesic protocols also worsen colorectal anastomotic blood flow.Supported in part by a grant from the Spanish Society of Digestive Diseases, Madrid, Spain. All tonometric catheters and drugs were donated by the Clinic University Hospital of Valencia, Spain.Read at the meeting of The American Society of Colon and Rectal Surgeons, Seattle, Washington, June 9 to 14, 1996. 相似文献
20.
M Marín-Padilla 《The Journal of comparative neurology》1992,321(2):223-240
The prenatal development of the mammalian neocortex has been analyzed, with the rapid Golgi method, in a variety of experimental animals (hamster, mouse, rat, and cat) and in humans. A new developmental conception of the structural organization of the mammalian neocortex is discussed. Neocortical development begins with the establishment of the primordial plexiform layer (PPL) which precedes and is a prerequisite for the subsequent formation of the cortical plate (CP). The formation of the CP occurs, in its entirety, within the PPL. During its development, three fundamental neuronal events occur: migration, early differentiation, and late maturation. All migrating neurons, travelling on radial glial fibers, reach layer I, develop an apical dendrite, and establish contacts with its elements. These newly differentiated neurons assume similar morphology resembling embryonic pyramidal cells. As such, an early differentiation stage common to all neurons of the CP is established. During the late maturation stage, all CP neurons acquire their specific phenotypic structural and functional features. Only pyramidal neurons retain and expand their original connections with layer I while other neuronal types lose these connections. The pyramidal cell is redefined in developmental terms: the neocortex's pyramidal cell is both structurally and functionally locked into position between layer I and the cortical depth of its soma. During mammalian evolution pyramidal cells are forced to structurally and functionally elongate their apical dendrite outwardly to accommodate an increasing amount of information without losing either their original anchorage to layer I or their cortical depth. This unique property of pyramidal neurons is considered to be a mammalian innovation. Based on these observations, a unifying developmental cytoarchitectonic theory applicable to all mammals is proposed. The theory considers the CP to be a mammalian innovation and to represent a single, stratified, and expanding telencephalic nucleus. The theory envisions the mammalian neocortex as an open biological system capable of progressive expansion by the recruitment and transformation of primitive neurons from upper layer II into pyramidal cells. Hence, the number of pyramidal cell strata increases over the course of mammalian phylogeny. The developmental roles of layer I in the migration of neurons, formation of the CP, unique morphology of pyramidal cells, and overall structural organization of the mammalian neocortex are emphasized. 相似文献