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11.
Giulio Balbontin Dario Dainelli Maurizio Galimberti Guglielmo Paganetto 《Macromolecular chemistry and physics.》1992,193(3):693-703
Thermal characterization was carried out on highly stereoregular and regioregular syndiotactic polypropene (sPP) obtained with isopropylidene(cyclopentadienyl)(9-fluorenyl)zirconium dichloride and methylaluminoxane. The influence of molecular weight and syndiotacticity degree on the thermodynamic melting point (T°m) of sPP were separately investigated by examining samples with a fully syndiotactic pentads content (rrrr) ranging from ca. 81% to ca. 94% and with an weight-average molecular weight (M?w) ranging from 9,6 · 104 to 17,3 · 104. Upon excluding any influence of the molecular weight, the correlation between the rrrr pentads content and the T°m of the samples led to the extrapolation of the thermodynamic melting point for a fully syndiotactic polypropene. 相似文献
12.
Hydrocephalus and cavernoma of the cauda equina 总被引:1,自引:0,他引:1
The association of a tumor of the cauda equina and hydrocephalus is unusual. We report a case of hydrocephalus with normal pressure associated with an equally rare affliction, a cavernous angioma of the cauda equina, which regressed after surgical ablation. The physiological mechanism involved is discussed. 相似文献
13.
F. M. González Valverde F. Mauri Barberá M. Molto Aguado N. Torregrosa A. Hernández Quiles F. Menárguez Pina M. J. Gómez Ramos M. García Real J. A. Barreras Mateos J. L. Vázquez Rojas 《European Surgery》2004,36(4):253-256
Summary BACKGROUND: Endometriosis is a relatively common pathology in women of childbearing age and of low parity but rarely shows
extraperitoneal involvement. The main aim of this paper is to raise the attention of specialists to the necessity of carrying
out penetrating diagnosis of nonspecific extraperitoneal masses occurring in women of reproductive age. METHODS: We performed
a retrospective review of six patients diagnosed with extraperitoneal endometriosis who were treated at the Vega Baja University
Hospital (Spain) during the last 5 years. RESULTS: Surgical treatment had positive results in five patients. The preoperative
diagnosis was correctly made in only two patients. The accurate aetiology of endometriosis remains unknown and diagnosis is
based on clinical and cytopathological findings. CONCLUSIONS: Surgical treatment of extraperitoneal endometriosis is recommended.
However, postoperative follow-up is obligatory and hormonal suppressive therapy may be necessary. Medical treatment with gestagens,
Danazol, or agonists of the gonadotropin-releasing hormone are ineffective in endometriomas which are bigger than 2 cm.
相似文献
14.
15.
Dario Giugliano Antonio Ceriello Katherine Esposito 《Journal of the American College of Cardiology》2006,48(4):677-685
Reducing the incidence of coronary heart disease with diet is possible. The main dietary strategies include adequate omega-3 fatty acids intake, reduction of saturated and trans-fats, and consumption of a diet high in fruits, vegetables, nuts, and whole grains and low in refined grains. Each of these strategies may be associated with lower generation of inflammation. This review examines the epidemiologic and clinical evidence concerning diet and inflammation. Dietary patterns high in refined starches, sugar, and saturated and trans-fatty acids, poor in natural antioxidants and fiber from fruits, vegetables, and whole grains, and poor in omega-3 fatty acids may cause an activation of the innate immune system, most likely by an excessive production of proinflammatory cytokines associated with a reduced production of anti-inflammatory cytokines. The whole diet approach seems particularly promising to reduce the inflammation associated with the metabolic syndrome. The choice of healthy sources of carbohydrate, fat, and protein, associated with regular physical activity and avoidance of smoking, is critical to fighting the war against chronic disease. Western dietary patterns warm up inflammation, while prudent dietary patterns cool it down. 相似文献
16.
Jorge Polónia Jo?o Maldonado Rui Ramos Susana Bertoquini Mary Duro Cristina Almeida Jo?o Ferreira Loide Barbosa José Alberto Silva Luís Martins 《Revista portuguesa de cardiologia》2006,25(9):801-817
BACKGROUND: Portugal has one of the highest mortality rates from stroke, a high prevalence of hypertension and probably a high salt intake level. AIM: To evaluate Portuguese salt intake levels and their relationship to blood pressure and arterial stiffness in a sample of four different adult populations living in northern Portugal. METHODS: A cross-sectional study evaluating 24-hour urinary excretion of sodium (24 h UNa+), potassium and creatinine, blood pressure (BP), and pulse wave velocity (PWV) as an index of aortic stiffness in adult populations of sustained hypertensives (HT), relatives of patients with previous stroke (Fam), university students (US) and factory workers (FW), in the context of their usual dietary habits. RESULTS: We evaluated a total of 426 subjects, mean age 50 +/- 22 years, 56% female, BMI 27.9+/-5.1, BP 159/92 mmHg, PWV 10.4+/-2.2 m/s, who showed mean 24h UNa+ of 202 +/- 64 mmol/d, corresponding to a daily salt intake of 12.3 g (ranging from 5.2 to 24.8). The four groups were: HT: n = 245, 49 +/- 18 years, 92% of those selected, 69% treated, BP 163/94 mmHg, PWV 11.9 m/s, 24 h UNa+ 212 mmol/d, i.e. 12.4 g/d of salt); Fam: n = 38, 64 +/- 20 years, 57 % of those selected, BP 144/88 mmHg, PWV 10.5 m/s, 24 h UNa+ 194 mmol/d, i.e. 11.1 g/d of salt; US: n = 82, 22 +/- 3 years, 57% of those selected, BP 124/77 mmHg, PWV 8.7 m/s, 24h UNa+ 199 mmol/d, i.e. 11.3 g/d of salt; FW: n = 61, 39 9 years, 47% of those selected, BP 129/79 mmHg, PWV 9.5 m/s, 24 h UNa+ 221 mmol/d, i.e. 12.9 g/d of salt. The ratio of urinary sodium/potassium excretion (1.9 (0.4) was significantly higher in HT than the other three groups. In the 426 subjects, 24h UNa+ correlated significantly (p < 0.01) with systolic BP (r = 0.209) and with PWV (r=0.256) after adjustment for age and BP. Multivariate analysis showed that BP, age and 24h UNa+ correlated independently with PWV taken as a dependent variable. CONCLUSIONS: Four different Portuguese populations showed similarly high mean daily salt intake levels, almost double those recommended by the WHO. Overall, high urinary sodium excretion correlated consistently with high BP levels and appeared to be an independent determining factor of arterial stiffness. These findings suggest that Portugal in general has a high salt intake diet, and urgent measures are required to restrict salt consumption in order to prevent and treat hypertensive disease and to reduce overall cardiovascular risk and events. 相似文献
17.
Adoniram M Figueiredo Renato S Poggetti Fabio G Quintavalle Belchor Fontes Moise Dalva Riad N Younes Fabio B Jatene Dario Birolini 《World journal of emergency surgery : WJES》2007,2(1):5
Background
Heart chambers rupture in blunt trauma is uncommon and is associated with a high mortality. The determinant factors, and the incidence of isolated heart chambers rupture remains undetermined. Isolated rupture of the right atrium appendage (RAA) is very rare, with 8 cases reported in the reviewed literature. The thin wall of the RAA has been presumed to render this chamber more prone to rupture in blunt trauma. 相似文献18.
A Rangel-Abundis R Olvera J Cordero E Cordero M A Ramos 《Gaceta médica de México》1991,127(3):253-256
The authors present the clinical case of a 31 year female with systemic vascular hypertension secondary to a 65 percent unilateral fibromuscular renal artery stenosis. The centellographic study demonstrated hypoperfusion on the right kidney and serious functional damage; the patient was subject to intraluminal renal angioplasty resulting in right renal arterial thrombosis, which was treated successfully with intra-arterial and intravenous streptokinase infusion. Following the thrombotic therapy, recanalization of the thrombosed artery and normal renal excretion of the contrast substance was observed. 相似文献
19.
Ilham Bettahi David Pozo Carmen Osuna Russel J. Reiter Dario Acuña-Castroviejo Juan M. Guerrero 《Journal of pineal research》1996,20(4):205-210
Abstract: In this report, rat hypothalamic nitric oxide synthase (NOS) activity is shown to be partially inhibited by physiological concentrations of the pineal hormone melatonin. In vitro studies demonstrate that 1 nM melatonin, which approximates the physiological concentration of the hormone at night, significantly inhibited NOS activity. In vivo studies show that administering melatonin or collecting the hypothalamus from animals at night, when endogenous melatonin levels are elevated, results in a significant decrease of NOS activity. Results also show that calmodulin may be involved in this process since its presence in the incubation medium prevents the inhibitory effect of melatonin on NOS activity. 相似文献
20.
A series of intradiscal injections of chondroitinase ABC was performed in 31 young adult rabbits. Roentgenograms were taken immediately postinjection and were repeated at two, three, five, six, seven, or nine days after injection. All had roentgenographic evidence of disc space narrowing at all stages after the injection. Histologic evaluation of safranin-O fast green-stained sections indicated degradation of proteoglycans in the annulus fibrosus of chondroitinase ABC-injected discs. The cells of the chondroitinase ABC-injected discs, the end plates, and the growth-plate areas of adjacent vertebral bodies appeared unaffected. 相似文献