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排序方式: 共有666条查询结果,搜索用时 17 毫秒
1.
This study investigated the extent of impairment in functional parameters of liver mitochondria from rats treated for 60 days with hexachlorobenzene (HCB). A constant amount of mitochondrial uncoupling was found throughout the treatment period. At the same time a nearly constant amount of pentachlorophenol was detected in these mitochondria. In contrast, the level of mitochondrial porphyrins increased progressively. There was good correlation between the concentration of mitochondrial pentachlorophenol and the degree of uncoupling of oxidative phosphorylation. 相似文献
2.
Cell proliferation in breast cancer is a major determinant of clinical outcome in node-positive but not in node-negative patients. 总被引:2,自引:0,他引:2
Davide Treré Claudio Ceccarelli Mario Migaldi Donatella Santini Mario Taffurelli Elena Tosti Pasquale Chieco Massimo Derenzini 《Applied immunohistochemistry & molecular morphology》2006,14(3):314-323
The growth rate of a tumor cell population depends on two major factors: the percentage of proliferating cells (cell growth fraction) and the rapidity of their duplication (cell proliferation rate). The authors evaluated the prognostic and predictive value of both kinetics parameters in a large series of breast cancer patients (n=504). The cell growth fraction was determined by MIB-1 immunostaining, the cell proliferation rate by AgNOR analysis. Ki-67 LI (labeling index) and AgNOR area were significantly associated with histotype, histologic grade, tumor size, estrogen/progesterone receptor status, patient age, and lymph node involvement (P<0.005). In the entire series of patients, both kinetics variables were significantly and independently associated with the clinical outcome, but their prognostic relevance was quite different when node-negative and node-positive patients were considered separately. Although in node-positive patients Ki-67 LI and AgNOR area were the unique independent predictors of disease-free and overall survival, they were excluded by the multivariate Cox model in node-negative patients, where only tumor size and estrogen receptor status retained a significant P-value. These results show that in breast carcinoma the cell growth fraction and the cell proliferation rate have a different prognostic impact with respect to the lymph node status and are major determinants of clinical outcome in node-positive patients only. Within this subgroup, the rapidity of cell proliferation as assessed by AgNOR analysis also served as a sensitive predictor of the response to adjuvant treatments. 相似文献
3.
M P Foschini E Fulcheri P Baracchini C Ceccarelli C M Betts V Eusebi 《Human pathology》1990,21(8):859-865
Three cases of a squamous cell carcinoma with a prominent myxoid stroma are reported. One case in a 70-year-old woman had presented as a lump in the breast, the other two presented as polypoid lesions of the larynx and cervix uteri in a 65-year-old man and 61-year-old woman, respectively. The carcinomatous component was immersed in abundant extracellular mucosubstances. In addition to occasional squamous pearls, it displayed immunocytochemical evidence of high-weight keratin present in the neoplastic cells and, in one case, desmosomal attachment under electron microscopy. The extracellular mucosubstances proved to be similar to those seen in connective tissue. The differential diagnosis with histologically similar lesions has been taken into consideration, and it has been suggested that this newly described entity showing abundant myxoid stroma has to be distinguished from numerous benign and malignant myxoid soft tissue tumors. 相似文献
4.
BACKGROUND: The supply of high amounts of calcium (Ca) and phosphorus (P) during total parenteral nutrition (TPN) is matter of concern because of the risk associated with calcium phosphate precipitation. The in vitro Ca-P compatibility in ready-for-use TPN solutions after the addition of different concentrations of inorganic phosphate or d-fructose-1,6-diphosphate (FDP) and calcium chloride was evaluated. METHODS: Four series of experiments for each Ca + P couple were carried out by varying amino acid concentrations (2% or 4%), temperature (25 degrees C or 37 degrees C), and pH. The extent of precipitation was estimated by visual inspection and particle count. The areas of maximal compatibility (ie, areas showing the complete absence of precipitates) were drawn from the precipitation curves. RESULTS: The precipitation extent was considerably higher in conditions mimicking body environment for both Ca + P couples. The compatibility area at 37 degrees C and 2% amino acid for CaCl2 + Na2HPO4 admixtures was included within 2.50 mmol/L CaCl2 and 2.22 mmol/L Na2HPO4, whereas that for CaCl2 + FDP was within 33.3 mmol/L CaCl2 and 10.0 mmol/L FDP (20 mEq/L of P). Unlike inorganic calcium phosphate, FDP dicalcium salt precipitation was kinetically delayed and was only minimally enhanced by decreasing amino acid concentration. CONCLUSIONS: Our data indicated that the use of FDP as the P source in parenteral nutrition solutions was effective in avoiding the life-threatening calcium phosphate precipitation. Thus, the addition of FDP to TPN admixtures represents a safe choice, allowing the simultaneous administration of high amounts of Ca and P in restricted fluid volumes, even at low amino acid concentrations. 相似文献
5.
Once more, the authors are confronted with the difficult interpretation of senological images. When reviewing the radiologic features of a series including the symptomatic, the asymptomatic and the male breasts, the goal is to relate the patterns to clinical and histologic findings in order to improve the perception of the radiologist himself in transferring and integrating the information. The final conclusions, after reviewing the images, are: a) for the correct interpretation of senological images, the sign must be correlated with clinical findings and with data from other modalities; b) the radiologist's attitude must be always investigative and never exhaustive, due to the variability of all factors, which sometimes make a judgement of "radiological tranquility" in the breast impossible; c) the radiologist must, nowadays, improve his perception of senological images, thus becoming the one who knows how to correlate clinics to the images. By increasing his perception, his interpretation capabilities will certainly increase too. 相似文献
6.
7.
Ceccarelli P Bigatello LM Hess D Kwo J Melendez L Hurford WE 《Anesthesia and analgesia》2000,90(2):482-488
Inhaled nitric oxide (NO) is a selective pulmonary vasodilator used to treat intraoperative pulmonary hypertension and hypoxemia. In contrast to NO delivered by critical care ventilators, NO delivered by anesthesia machines can be complicated by rebreathing. We evaluated two methods of administering NO intraoperatively: via the nitrous oxide (N(2)O) flowmeter and via the INOvent (Datex-Ohmeda, Madison, WI). We hypothesized that both systems would deliver NO accurately when the fresh gas flow (FGF) rate was higher than the minute ventilation (VE). Each system was set to deliver NO to a lung model. Rebreathing of NO was obtained by decreasing FGF and by simulating partial NO uptake by the lung. At FGF > or = VE (6 L/min), both systems delivered an inspired NO concentration ([NO]) within approximately 10% of the [NO] set. At FGF < VE and complete NO uptake, the N(2)O flowmeter delivered a lower [NO] (70 and 40% of the [NO] set at 4 and 2 L/min, respectively) and the INOvent delivered a higher [NO] (10 and 23% higher than the [NO] set at 4 and 2 L/min, respectively). Decreasing the NO uptake increased the inspired [NO] similarly with both systems. At 4 L/min FGF, [NO] increased by 10%-20% with 60% uptake and by 18%-23% with 30% uptake. At 2 L/min, [NO] increased by 30%-33% with 60% uptake and by 60%-69% with 30% uptake. We conclude that intraoperative NO inhalation is accurate when administered either by the N(2)O flowmeter of an anesthesia machine or by the INOvent when FGF > or = VE. IMPLICATIONS: Inhaled nitric oxide (NO) is a selective pulmonary vasodilator. In a lung model, we demonstrated that NO can be delivered accurately by a N(2)O flowmeter or by a commercial device. We provide guidelines for intraoperative NO delivery. 相似文献
8.
Michele Arcangelo Verdano Andrea Pellegrini Giacomo Scita Cosimo Costantino Francesco Ceccarelli 《Musculoskeletal surgery》2013,97(1):51-56
The rotator cuff tear is one of the most frequent musculoskeletal disorders, but the real incidence is not clearly known because it’s usually asymptomatic, even if it’s more common in patients with shoulder pain (36 %). The prevalence of the complete tear among general population is estimated approximately around 20.7 % and it is more usual with the increasing of the age. The aim of this study is to evaluate a group of patients with any size of full-thickness cuff tear treated by arthroscopic technique, comparing the clinical and functional recovery (isokinetic, isotonic and isometric strength) with the un-operated side. Between October 2009 and June 2011, 74 patients, mean age 59 (20–72) years old, underwent arthroscopic treatment for rotator cuff tear. Forty-two patients were finally included in the study, 20 men and 22 women, mean age of 55 (20–68) years old. The mean follow-up was 12 months (6–23 months). The strength of each patient’s shoulder, both operated and un-operated, was evaluated using isokinetic, isotonic and isometric tests (BIODEX Medical System). The functional outcome showed no significant differences between operated and un-operated shoulder, confirmed by Constant–Murley score and DASH score. The isokinetic, isotonic and isometric tests are valid support to clinical evaluation in order to obtain an objective data on shoulder recovery. 相似文献
9.
Patrícia B. Cepeda Paulo S. Ceccarelli José L. Luque 《Acta parasitologica / Witold Stefański Institute of Parasitology, Warszawa, Poland》2011,56(3):270-273
A new species of Kritskyia Kohn, 1990 (Monogenea, Dactylogyridae, Ancyrocephalinae) is described from the urinary bladder of Salminus brasiliensis (Cuvier, 1816) (Characiformes, Characidae) from the Cuiabá River, the Pantanal wetlands, Brazil. The male copulatory apparatus
of the new species differs from those of other species of the genus by the presence of a bipartite accessory piece (distally
and proximally linked), one part grooved, serving as guide for distal portion of the MCO. Moreover, the vagina of the new
species differs from those of congeners by possessing distal digitiform processes. 相似文献
10.
L Chiovato P Vitti A Lombardi P Ceccarelli P Cucchi C Marcocci P Carayon A Pinchera 《Endocrinology》1988,123(2):1140-1146
The expression of the microsomal (M) antigen on the surface and in the cytoplasm of a strain of rat thyroid cells (FRTL-5) is under the regulation of TSH. In the present report the mechanism by which TSH induces such expression was investigated with the use of human microsomal antibody-positive serum and an indirect immunofluorescence technique. Studies were also performed to ascertain whether the M antigen of FRTL-5 cells could be identified with thyroid peroxidase (TPO), as suggested by recent data obtained in human thyroid tissue. Preabsorption experiments showed that, like solubilized human thyroid microsomes, purified human TPO completely abolished the binding of microsomal antibody to FRTL-5 cells. No inhibition was obtained by preabsorption with control human tissues (placenta, liver, and spleen) or human thyroglobulin, indicating that the antigen recognized by microsomal antibody in FRTL-5 cells was TPO. After 72 h of TSH withdrawal from the culture medium the M/TPO antigen disappeared from the surface and the cytoplasm of FRTL-5 cells. Readdition of TSH (250 microU/ml) to the culture medium of cells lacking the M/TPO antigen elicited its reappearance within 24-48 h. This effect of TSH was prevented by 10 microM cycloheximide or 0.5-5 micrograms/ml actinomycin D. Two well known stimulators of the adenylate cyclase-cAMP system, cholera toxin and forskolin, mimicked TSH in inducing the reappearance of the M/TPO antigen. A similar effect was observed with use of the phosphodiesterase inhibitor isobutylmethylxanthine. Reappearance of M/TPO antigen was also produced by the cAMP analog 8-bromo-cAMP. The tumor promoter 12-O-tetradecanoyl-phorbol 13-acetate, which stimulates thyroid cell growth through a cAMP-independent pathway, was ineffective in inducing the M/TPO antigen in FRTL-5 cells. The present data indicate that 1) thyroid peroxidase accounts for most, if not all, of the microsomal antigen of FRTL-5 cells; and 2) TSH modulates the expression of the M/TPO antigen in FRTL-5 cells by a mechanism that involves cAMP production and requires mRNA formation and subsequent protein synthesis. 相似文献