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41.
The present work is a study of the plastic capacity of the peripheral nervous system subjected to different aggressions in the case of 28 rats of the Wistar breed. They were divided into four groups: 1) sympathetic deafness (n=9); 2) parasympathetic deafness (n=9); 3) evaluation of regeneration (n=9); 4) control group (n=5). An image analyser was used to study the acetylcholinesterase (AChE) and Tyrosine Hydroxylase (TH) positive ganglionic neurones of the pelvic ganglion (GP) as well as the dorsal ganglions (GRD) compared with the control group. With group 3 a study was also made of the possible plasticity of the transacted axons using a wheat germ agglutinin conjugated-horseradish peroxidase (WGA-HRP) neurotracer. The statistical study was carried out by means of the analysis of variance (ANOVA), Fisher test and Scheffe method, with a p<0.05 taken as significant. The results show the predominant role of the pelvic nerve in the modulation of the plastic changes produced at the ganglionic level, with a lesser influence of the hypogastric nerve. Further studies are needed in order to define the specific role of each of these in the act of miction. 相似文献
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R. Rodríguez-Puertas A. Pazos J. J. Zarranz J. Pascual 《Journal of neural transmission (Vienna, Austria : 1996)》1994,8(3):161-169
Summary
3H-hemicholinium-3 (3H-HC-3) binding, a marker of the presynaptic high-affinity choline uptake carrier (HACU), was measured by autoradiography in several brain regions of 17 Alzheimer's disease (AD) patients and of 11 matched controls. A significant decrease in the density of3H-HC-3 binding sites was found in entorhinal cortex, hippocampus and layers I–III of the frontal cortex. By contrast, in the caudate-putamen the number of3H-HC-3 binding sites in AD cases was comparable to that of control striata. These data concur with previous results using classical presynaptic markers and reflect the loss in the activity of HACU, and, hence, in the synthesis of acetylcholine, that selectively occurs in cortical areas of AD brains due to the degeneration of presynaptic cholinergic terminals arising from the basal forebrain. However, the relatively low mean reduction in HACU in cortical areas (–40%), together with the apparent indemnity of this marker in certain severely demented AD cases, suggest that AD dementia cannot be explained simply by the loss of presynaptic terminals originating in the basal forebrain. These data seem to be a good explanation for the poor response to cholinergic replacement in AD. 相似文献
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The clinical usefulness of the renal allograft biopsy in the cyclosporine era: a prospective study 总被引:9,自引:0,他引:9
Pascual M Vallhonrat H Cosimi AB Tolkoff-Rubin N Colvin RB Delmonico FL Ko DS Schoenfeld DA Williams WW 《Transplantation》1999,67(5):737-741
BACKGROUND: The renal allograft biopsy is generally accepted as the gold standard for clarifying the cause of renal dysfunction. However, the clinical usefulness of this procedure has rarely been studied prospectively, nor have most studies included follow-up of patients to delineate the influence of the biopsy on clinical outcome. In this study, we evaluated prospectively the clinical usefulness of the allograft biopsy in renal transplant recipients receiving cyclosporine (CyA). METHODS: During a 21-month period, 82 biopsies were performed. In 54 instances (47 patients), we outlined a presumed diagnosis and tentative treatment plan before the procedure. After the biopsy, a definitive diagnosis was made and an appropriate patient management approach was instituted. We analyzed the incidence of change in patient management that resulted from histological findings. All patients were followed to monitor their response to treatment and allograft survival. In cases of biopsy-proven acute cellular rejection (ACR) or cyclosporine (CyA) toxicity, clinical and laboratory data from the day of the biopsy were reviewed to determine their diagnostic value. RESULTS: One biopsy specimen was inadequate for definitive interpretation. The biopsy findings resulted in a change in patient management in 22 (41.5%) of the remaining 53 cases (change group). The incidence of altered patient management was 38.7% in biopsy specimens taken in the first month, 55.6% between 1 and 12 months, and 38.5% after 1 year posttransplantation. A change in management was required in 2 of 2 patients with chronic allograft dysfunction, in 44.4% of the 45 patients with acute allograft dysfunction, and in none of the patients with delayed graft function (n=6). Within the first week of treatment 19 of 22 (86.4%) in the change group and 25 of 31 (80.6%) in the no change group had a positive response to therapy. The 1-year allograft survival rate was also similar between the two groups. None of the clinical and laboratory data was useful in distinguishing ACR from CyA toxicity. CONCLUSIONS: Renal allograft biopsy findings alter patient management recommendations in approximately 40% of patients in whom a presumptive diagnosis had been made on the basis of clinical and laboratory findings. Patients who had a change in patient management because of biopsy findings demonstrated a response to therapy and allograft survival similar to those of patients who had no alteration in management plan after the biopsy. 相似文献
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48.
Gilbert JR Pascual M Schoenfeld DA Rubin RH Delmonico FL Cosimi AB 《Transplantation》1999,67(2):246-253
BACKGROUND: Due to the limited supply and increased demand for donor livers, waiting times are progressively lengthening, which may lead to transplantation at more advanced and less cost-effective stages of disease. The purpose of this study was to evaluate the outcomes and hospital charges of liver transplantation during two recent eras to identify areas for providing more cost-effective care. METHODS: A total of 144 primary liver allografts were performed from 1991 to 1996. Patient characteristics, outcome measures, and hospital charges were compared for patients receiving allografts between 1991 and 1993 (group A) versus those receiving grafts between 1994 and 1996 (group B) using unpaired Student t tests for continuous data and chi-squared tests for categorical data. RESULTS: In comparing groups A and B, no significant differences in patient demographics, relative contraindications, or indication for transplantation existed; median waiting time from date of listing until transplant increased from 88 days to 159 days; and a shift in UNOS priority status at time of transplantation occurred, as the percentage of patients requiring inpatient care increased from 58% to 75% (P=0.034). Despite this, patient hospital and 1-year survival significantly improved from 75.0% to 90.3% (P=0.016), and from 68.1% to 88.9% (P=0.002), respectively. Total hospital charges, without correction for inflation, were $174,908+/-16,388 in A and $193,525+/-14,444 in B (P=0.288). The increased charges were associated with longer inpatient length of stay (LOS) before transplant, resulting in increased pretransplant charges from $24,088+/-4134 (A) to $39,490+/-6,196 (B) (P=0.011). Room and service (54%) was the largest pretransplant contributor to charges, while blood products (23%), room and service (21%), organ acquisition (13%), and operating room charges (11%) contributed the most after transplant. CONCLUSIONS: Longer waiting times resulting in transplantation at later stages of disease have occurred, leading to longer pretransplant LOS and its associated charges. Despite more advanced disease, patient survival rates have significantly improved with fewer infection-related deaths. LOS pretransplant, blood products, and operating room services represent potential areas for providing more cost-effective care. 相似文献
49.
Antonio Melgarejo-Moreno José Galcerá-Tomás Arcadio García-Alberola Pascual Rodríguez-García Antonio González-Sánchez 《European journal of epidemiology》1999,15(7):621-629
Age and female gender have been associated with poor prognosis in acute myocardial infarction (AMI). Data currently available about the prognostic significance of gender in AMI might well have led to inappropriate/incomplete conclusions. A multicenter, prospective study on 1239 patients with AMI was conducted. Clinical characteristics, complications during the acute phase and one-year follow-up were monitored. Women constituted 24.1% of all patients. Female patients were older with more prevalence of diabetes, hypertension, and previous congestive heart failure. Compared with men, the following complications were more frequently found in women: heart failure, 43% vs. 22% (p<0.001); reinfarction, 5% vs. 2% (p<0.05); use of pacemaker, 7% vs. 4% (p<0.05). Women had higher mortality: early, during the first 24 hours post-admission, 10.7 vs. 3.1%; in-hospital, 23% vs. 8.1%; and 1-year, 33.7% vs. 16% (p<0.001 for all the 3 cases of mortality). In the age-groups considered (<65, 65–74, and 75 years), 1-year mortality increased exponentially with ageing in men: 7.8%, 21.3%, and 38.9%, whereas in women the figures were: 15.3%, 41.5%, and 38.8%. Multivariate analysis showed that, among other variables, age and female gender had independent prognostic value for in-hospital mortality whereas gender lost its prognostic significancy for 1-year mortality. Multivariate analysis restricted to those patients aged over 75 years showed that age but not gender had independent prognostic value. In conclusion, age and female sex have independent prognostic value for predicting mortality in patients with AMI. Mortality increases exponentially with ageing in men whereas it stabilises in the case of women over 65 years. Female gender loses its independent value for predicting mortality in patients over 75 years. 相似文献