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11.
Gianni Biolo Beniamino Ciocchi Manuela Stulle Arianna Piccoli Stefania Lorenzon Viviana Dal Mas Rocco Barazzoni Michela Zanetti Gianfranco Guarnieri 《Journal of renal nutrition》2005,15(1):49-53
Physical inactivity is associated with alteration of normal physiologic processes leading to muscle atrophy, reduced exercise capacity, insulin resistance, and altered energy balance. Bed rest studies in human beings using stable isotopes of amino acids indicate that muscle unloading decreases the turnover rates of muscle and whole-body proteins, with a prevailing inhibition of protein synthesis. In the fasting state, muscle and whole-body nitrogen loss was not accelerated during bed rest. In experimental postprandial states, the amino acid-mediated stimulation of protein synthesis was impaired, whereas the ability of combined insulin and glucose infusion to decrease whole-body proteolysis was not affected by muscle inactivity. Thus, an impaired ability of protein/amino acid feeding to stimulate body protein synthesis is the major catabolic mechanism for the effect of bed rest on protein metabolism. This suggests that a protein intake level greater than normal could be required to achieve the same postprandial anabolic effect during muscle inactivity. Metabolic adaptation to muscle inactivity also involves development of resistance to the glucoregulatory action of insulin, decreased energy requirements, and increased insulin and leptin secretion. These alterations may lead to the development of the metabolic syndrome that is defined as the association of hyperinsulinemia, dyslipidemia, hypertension, hyperglycemia, and abdominal obesity. This cluster of metabolic abnormalities is a risk factor for coronary artery disease and stroke. Evidence indicates that exercise training programs may counteract all of these abnormalities both in healthy sedentary subjects and in patients affected by a variety of chronic disease states. 相似文献
12.
Onelio Geatti Brahm Shapiro Pier Giuseppe Orsolon Gianni Proto Ugo Paolo Guerra Francesco Antonucci Daniele Gasparini 《European journal of nuclear medicine and molecular imaging》1994,21(1):17-22
Technetium-99m methoxyisobutylisonitrile (MIBI), like thallium-201, has recently been introduced as a myocardial perfusion agent and is now also showing very promising results in parathyroid scintigrapy. The results of 201Tl/99mTc-pertechnetate and 99mTc-MIBI/99mTc-pertechnetate subtraction scintigraphy, ultrasonography and computed tomography are presented in a series of 43 patients operated on for hyperparathyroidism. All four imaging modalities were confirmed to be reliable, scintigraphy being the most accurate. Sensitivities ranged from 81% to 95%, that of 99mTc-MIBI being the highest. Moreover this tracer, which has more favourable physical and also biochemical properties, yielded images of superior quality. This allowed localization of the lesion by visual inspection only in as many as 86% of the patients with positive 99mTc-MIBI/99mTc-pertechnetate subtraction scintigraphy. We believe that the higher sensitivity, superior image quality and lower cost of 99mTc-MIBI imaging will make 99mTc-MIBI the new radiopharmaceutical of choice for parathyroid scintigraphy (when one takes into account the stability of labelling with large activities it is possible to perform three or four cardiac studies together with one parathyroid scintigraphic examination using one lyophililzed vial). 相似文献
13.
Summary Primary colon tumors of different sizes and malignancy, chemically induced by methylazoxymethanol in outbred CF-1 mice, were used to investigate the antitumor effects of 5-Fluorouracil (5FU) and cis-diammine-dichloroplatinum (DDP), given weekly i.v. as single agents or in combination. When single-drug chemotherapy was tested, DDP showed higher efficacy than 5FU. In fact, in two separate experiments a significant reduction (P(0.05) of tumor number (TN) and tumor burden was obtained by treatment with the optimal dose of DDP (4.5 mg/kg per injection) and not by that of 5FU (52 mg/kg). When the two drugs were combined (24-h interval), studies carried out on healthy mice treated weekly i.v. showed a lower toxicity with the same doses given in the sequence 5FU-DDP than in the opposite sequence. The two drugs, delivered in the sequence 5FU followed by DDP, statistically reduced the TN and total tumor burden compared to control mice (P(0.05). On the other hand, the same doses in the sequence DDP followed by 5FU did not attain significant tumor reduction. The sequence dependence of the activity and toxicity of the 5FU and DDP combination observed in this experimental model should be taken into account in the design of clinical trials.Abbreviations used MAM
methylazoxymethanol acetate
- 5FU
5Fluorouracil
- DDP
cis-diamminedichloroplatinum
- TN
tumor number
- TTB
total tumor burden
- Ara-C
cytosine-arabinoside
This work was partially supported by Grant N. 84.00746.44 of Finalized Project Oncology of CNR (Rome, Italy) 相似文献
14.
C. Stellato A. de Paulis G. de Crescenzo F. Tatangelo O. Rickler G. Marone 《Inflammation research》1992,36(Z2):C195-C198
We investigated thein vitro effects of increasing concentrations (10–5–10–3
M) of four muscle relaxants (succinylcholine, d-tubocurarine, vecuronium and atracurium) on histamine release (HR) from human peripheral blood basophils and mast cells isolated from lung parenchyma (HLMC) and skin tissues (HSMC). Basophils released less than 5% of their histamine content when incubated with any one of the muscle relaxants. In contrast, mast cells showed a marked heterogeneity in their response. Succinylcholine did not induce HR from any type of mast cell, and only high concentrations of d-tubocurarine (10–3
M) caused HR from HSMC and HLMC. Vecuronium concentration-dependently induced HR from HLMC and HSMC. Atracurium concentration-dependently caused marked HR from HLMC and HSMC up to a maximum of 46.2±15.1% and 30.6±6.0%, respectively. From both HLMC and HSMC HR caused by atracurium and vecuronium was extremely rapid (t1/2<1 min).=" the=" releasing=" activity=" of=" atracurium=" and=" vecuronium=" on=" hlmc=" and=" hsmc=" was=" reduced,=" but=" not=" abolished,=" by=" lowering=" the=" temperature=" of=" the=" incubation=" buffer=" to=" 22°c=" and=" 4°c.=" these=" results=" confirm=" that=" there=" are=" functional=" differences=" between=" human=" basophils=" and=" mast=" cells=" and=" among=" mast=" cells=" isolated=" from=" different=" anatomical=" sites=" in=" response=" to=" the=" muscle=" relaxants=">1> 相似文献
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17.
Maria Rosaria Raspollini Gianni Amunni Alessandro Villanucci Francesca Castiglione Duccio Rossi Degl'Innocenti Gianna Baroni Milena Paglierani Gian Luigi Taddei 《Applied immunohistochemistry & molecular morphology》2006,14(2):181-186
The bcl-2 protein is a membrane protein involved in prolonging cell survival by inhibiting apoptosis. The HER-2 oncogene, which is located on chromosome 17 and encodes for a tyrosine-kinase growth factor receptor, is amplified and HER-2/neu is overexpressed in 25% to 30% of breast carcinomas. The authors analyzed the bcl-2 expression and the bcl-2 gene and HER-2/neu overexpression and amplification in FIGO stage IIIC, serous, G3, ovarian carcinomas obtained from living patients who had no evident disease 5 years after primary treatment compared with ovarian carcinomas obtained from patients, matched for stage, grade of differentiation, and treatment, who had died of progression of disease no later than 2 years after primary treatment. bcl-2 overexpression was statistically correlated with progression of disease during first-line chemotherapy (P=0.021). The HER-2/neu status was found not to correlate with progression of disease during first-line chemotherapy. Both bcl-2 and HER-2/neu expression were not statistically associated with the clinical outcome of ovarian cancer patients. Gene amplification of the HER-2/neu chromosome 17 was found in all the HER-2/neu, 3+ score, positive-staining ovarian carcinomas. None of the analyzed samples revealed a translocation t(14;18)(q32;q21) in the bcl-2 gene. The knowledge of additional prognostic or even predictive factors, such as bcl-2 expression, in patients with advanced ovarian carcinoma before the primary chemotherapeutic treatment may help in the management of patients who require a more tailored treatment. In addition, the gene amplification of the HER-2/neu suggests that HER-2 is a potential target for treatment in ovarian cancer. 相似文献
18.
Raspollini MR Castiglione F Garbini F Villanucci A Amunni G Baroni G Boddi V Taddei GL 《International journal of surgical pathology》2005,13(2):135-142
We analyzed in advanced ovarian serous G3 carcinoma the correlation between epidermal growth factor receptor (EGFR) overexpression and tumor angiogenesis and their relation with clinical outcome. Microvessel density (MVD) and vascular endothelial growth factor (VEGF) were statistically correlated with disease-free interval and death from disease both in univariate and multivariate analyses while EGFR expression was not correlated with clinical outcome. MVD was significantly associated with progression of disease during chemotherapy while VEGF and EGFR expression were not correlated with responsiveness to chemotherapy (Fisher's exact test). VEGF expression was correlated with MVD (Fisher's exact test). EGFR showed a trend to correlation with MVD. Further studies focusing on the use of angiogenesis inhibitors in addition to EGFR inhibitors on ovarian carcinoma cells may produce therapeutic strategies in the selection of tailored therapies in ovarian cancer patients. 相似文献
19.
A new one-step computational procedure is presented for estimating the parameters of the nonlinear three-element windkessel
model of the arterial system incorporating a pressure-dependent compliance. The data required are pulsatile aortic pressure
and flow. The basic assumptions are a steadystate periodic regime and a purely elastic compliant element. By stating two conditions,
zero mean flow and zero mean power in the compliant element, peripheral and characteristic resistances are determined through
simple closed form formulas as functions of mean values of the square of aortic pressure, the square of aortic flow, and the
product of aortic pressure with aortic flow. The pressure across as well as the flow through the compliant element can be
then obtained so allowing the calculation of volume variation and compliance as functions of pressure. The feasibility of
this method is studied by applying it to both simulated and experimental data relative to different circulatory conditions
and comparing the results with those obtained by an iterative parameter optimization algorithm and with the actual values
when available. The conclusion is that the proposed method appears to be effective in identifying the three-element windkessel
even in the case of nonlinear compliance. 相似文献