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21.
Billette J; Janse MJ; van Capelle FJ; Anderson RH; Touboul P; Durrer D 《The American journal of physiology》1976,231(4):1129-1139
22.
From 1976 to June 1982, 237 patients with clinical suspicion of hepatic malignant disease underwent guided percutaneous fine-needle aspiration biopsy of the liver. Of these, 12 were diagnosed cytologically as "hepatocellular carcinoma" and this diagnosis was confirmed in the follow-up of all cases. On the basis of the cytomorphologic features observed in the aspirates, the tumor was subclassified into three types; well differentiated, pleomorphic large cell; and poorly differentiated. The various cytologic appearances of different types of hepatocellular carcinoma are presented and illustrated. Cytomorphologically, these three types of hepatocellular carcinoma were distinctly different and their cytomorphologic features were also sufficiently distinctive from those of secondary hepatic cancer to be diagnostic. Guided percutaneous fine-needle aspiration biopsy of the liver appears to be a definitive minimally invasive means of establishing the diagnosis of hepatocellular carcinoma, and promises to be a valuable diagnostic procedure for potentially resectable localized hepatocellular carcinoma. 相似文献
23.
Habib Ndema Steyn Petrus S. Boydell Victoria Cordero Joanna Paula Nguyen My Huong Thwin Soe Soe Nai Dela Shamba Donat Kiarie James 《Health services & outcomes research methodology》2021,21(2):188-205
Health Services and Outcomes Research Methodology - An interrupted time series with a parallel control group (ITS-CG) design is a powerful quasi-experimental design commonly used to evaluate the... 相似文献
24.
Daniel Viegas Pedro Batista Paulo Oliveira Carlos Silvestre 《Optimal control applications & methods.》2021,42(1):126-143
This article addresses the problem of distributed controller design for linear discrete‐time systems. The problem is posed using the classical framework of state feedback gain optimization over an infinite‐horizon quadratic cost, with an additional sparsity constraint on the gain matrix to model the distributed nature of the controller. An equivalent formulation is derived that consists in the optimization of the steady‐state solution of a matrix difference equation, and two algorithms for distributed gain computation are proposed based on it. The first method consists in a step‐by‐step optimization of said difference matrix equation, and allows for fast computation of stabilizing state feedback gains. The second algorithm optimizes the same matrix equation over a finite time window to approximate asymptotic behavior and thus minimize the infinite‐horizon quadratic cost. To assess the performance of the proposed solutions, simulation results are presented for the problem of distributed control of a quadruple‐tank process, as well as a version of that problem scaled up to 40 interconnected tanks. 相似文献
25.
A Silvestre García C Colomer Revuelta A Nolasco Bonmatí L González Sáez C Alvarez-Dardet Díaz 《Gaceta sanitaria / S.E.S.P.A.S》1990,4(20):189-192
The study of the determinants of disease-related lifestyles may be relevant for better understanding the potential of health policies. In the present work, results of the analysis of the Elche Healthy Cities Interview Survey prevalence of some disease related lifestyles (physical activity level, cigarette consumption, and alcohol intake) are presented according to economic level as measured by monthly family income, 573 people randomly selected from the town rolls were interviewed at home. No associations were found between economic level and alcohol intake or present smoking status. But, trying to stop smoking and regular exercise were more frequent behaviors in higher economic groups. The ratio of prevalence of regular exercise was 1.73 in favor of the highest economic levels. The gradient found was statistically significant (chi 2 for trend = 17.4, p less than 0.01). The results may be of relevance when implementing health policies to overcome inequalities in health: "unequal interventions" may be more adequate. 相似文献
26.
Ramn Alvarenga Ariadna Gonzlez del Angel Victoria del Castillo Silvestre García de la Puente Irene Mauln Alessandra Carnevale 《American journal of medical genetics. Part A》1995,56(2):173-175
Several patients with the Silver-Russell syndrome (SRS) attending our Genetics Clinic were diagnosed as having persistent metabolic acidosis. Since this abnormality has not been reported previously in the SRS, we reexamined 33 SRS patients to evaluate the frequency and type of metabolic acidosis, the clinical and laboratory findings, and the growth pattern in SRS patients with and without metabolic acidosis. Among them, 14 had a consistent decrease in HCO levels. Renal studies in acidotic patients showed urine pH of 5.8 and 24 h urine calcium of <2.4 mg/kg/24 h; serum creatinine, excretion of glucose, and aminoacids were normal, as were renal ultrasound and excretory urography findings. These data supported the diagnosis of renal tubular acidosis, probably type II; the patients were treated with oral bicarbonate and acidosis was corrected successfully. Clinical manifestations were similar in acidotic and non-acidotic patients. The nutritional indices at diagnosis and at last evaluation (at least 8 months after diagnosis) were abnormally low in all patients; however, acidotic patients, treated with bicarbonate, showed an improvement of nutritional status particularly in the weight/height index, although the difference between groups after follow-up did not reach statistical significance. We suggest that metabolic acidosis due to renal tubular acidosis, probably type II, may occur in children with the SRS and should be looked for and treated in all patients. © 1995 Wiley-Liss, Inc. 相似文献
27.
Quantitative nuclear morphometry (QNM) provides a reliable, reproducible method for measuring the degree of nuclear pleomorphism, a qualitative parameter widely incorporated into histopathological grading schemes. Nuclear shape has successfully been shown to predict primary prostate adenocarcinoma metastatic potential. This investigation utilized QNM to measure the nuclear pleomorphism of 50 patients with primary laryngeal squamous cell carcinoma to determine whether this computer-assisted method could discriminate between those patients with and without cervical metastases. Nuclear cross-sectional area and nuclear roundness as determined by QNM could not discriminate between patients with and without cervical metastases, though significant alterations in nuclear morphology exist between normal laryngeal squamous epithelium and laryngeal squamous cell carcinoma. 相似文献
28.
29.
J S Silvestre A G Fernández J M Palacios 《Journal of psychopharmacology (Oxford, England)》1999,13(3):274-277
The objective of the present study was to assess the behavioural effects of rolipram, a specific cAMP phosphodiesterase (PDE4) inhibitor, in the elevated plus-maze (EPM) test in rats. Results showed that rolipram at the highest dose tested (0.1 mg/kg) increased the percentage of both time spent and entries into open arms, although a decrease of locomotor activity in the EPM test was also observed. In contrast, diazepam (3.0 mg/kg) exhibited the typical profile of an anxiolytic in the EPM test, increasing the percentage of time spent and entries into open arms as well as locomotor activity. A posterior statistical analysis, however, established that the effects of both rolipram and diazepam on parameters denoting anxiolytic-like activity were statistically independent from those reflecting locomotor activity reduction. Furthermore, the effects of both rolipram and diazepam were shown to be distinct from those exhibited by tricyclic antidepressant imipramine which did not show any anxiolytic-like effects in the EPM test, although a reduction of locomotor activity was also detected. Although these preliminary results suggest that rolipram may have some anxiolytic-like properties on the EPM test in rats, such an interpretation should be taken cautiously due to the observed effects on locomotor activity, which could complicate the interpretation of results from rolipram and other PDE4 inhibitors in the current test and in other anxiety animal models. 相似文献
30.
R. Guitart X. Guerrero A. M. Silvestre J. M. Gutiérrez R. Mateo 《Archives of environmental contamination and toxicology》1996,30(1):79-83
A simple and rapid method was developed for the simultaneous determination of fatty acids, organochlorine pesticides, and polychlorinated biphenyl (PCB) congeners in the same sample in order to explore possible connections between levels of contaminants and fatty acid composition. The method was applied to samples of melon, cerebrum, cerebellum, lung, liver, kidneys, and skeletal muscle obtained from 5 male and 5 female striped dolphins (Stenella coeruleoalba) found stranded in 1990 in the northeastern Spanish coasts during the morbillivirus epizootic that affected this cetacean in the Mediterranean Sea. The results indicate that PCBs were dominant in all tissues, with the highest geometric mean concentration being found in melon (903 g g–1 wet wt); DDTs were also found at high concentrations (111 g g–1 wet wt, in melon). Statistical analysis indicate that organochlorine concentration was correlated with the fatty acid composition of tissues, although some of these variations can be interpreted as a consequence of a shift in the diet produced in the striped dolphin population. However, other changes such as the negative correlation with arachidonic acid may suggest that the eicosanoid production could have been affected by the extremely high concentrations of PCBs and DDTs. 相似文献