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101.
Maria?Rosaria?CardilloEmail author Vincenzo?Gentile Mauro?Ciccariello Laura?Giacomelli Silvio?Messinetti Franco?Di Silverio 《BMC cancer》2005,5(1):111
Background
The aim of the study was to investigate whether p503S, p504S and p510S gene expression in peripheral-blood be useful as a diagnostic or prognostic marker of prostatic cancer. 相似文献102.
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The prevalence of obesity has reached epidemic dimension in industrialized countries and it is known that obesity is associated with increased risk of cardiovascular morbidity and mortality. Commonly, obesity is defined by the Body Mass Index (BMI). However, BMI fails to consider body fat distribution. The relationship between the risk of metabolic-cardiovascular diseases and body fat distribution indices such as the waist-to-hip ratio (WHR) and the waist circumference, rather than measures of the degree of body fatness as expressed by BMI, has long been recognized. Recently, clinical and epidemiological research has found waist circumference to be the best anthropometric indicator of both total body fat and intra-abdominal fat mass. Android or visceral obesity is associated with metabolic syndrome and increased cardiovascular morbidity and mortality through a variety of molecular mechanisms possibly linking the metabolic syndrome to hemostatic and vascular abnormalities. Obesity guidelines suggest the need for weight reduction using behavioural change to reduce caloric intake and increasing physical activity. A realistic goal for weight reduction is to reduce body weight by 5% to 10% over a period of 6 to 12 months. Combined intervention of a low calories diet, increased physical activity, and behaviour therapy provides better outcomes for long-term weight reduction and weight maintenance than programs that use only one or two of these modalities. The drugs used to promote weight loss have been anorexic drugs or appetite suppressants. All classes of anorexic drugs affect neurotransmitters in the brain. The new agent sibutramine has norepinephrine and serotonin effects. Another new agent, orlistat, has a different mechanism of action, the reduction of fat absorption. Weight loss drugs approved by the FDA for long-term use may be useful as an adjunct to diet, physical activity and behaviour therapy for patients with a BMI of > or =30 with no concomitant obesity-related risk factors or diseases, and for patients with a BMI of > or =27 with concomitant obesity-related risk factors or diseases. 相似文献
105.
The effect of PD-168077 (N-methyl-4-(2-cyanophenyl)piperazynil-3-methylbenzamide maleate), a selective D4 dopamine receptor agonist, injected into the paraventricular nucleus of the hypothalamus on penile erection was studied in male rats. PD-168077 (1-200 ng) induced penile erection in a dose-dependent manner. The minimal effective dose was 50 ng, while the maximal response was found with 200 ng of the compound, which increased penile erection episodes from 0.3+/-0.03 to 1.7+/-0.21. The proerectile effect of PD-168077 was reduced almost completely by L-745,870 (3-(4-[chlorophenyl]piperazin-1-yl)-methyl-1H-pyrrolo[2,3-B]pyridine trihydrochloride), a selective D4 dopamine receptor antagonist, (1 microg) given into the paraventricular nucleus before the D4 dopamine agonist, and by other nonselective dopamine receptor antagonists, such as haloperidol (1 microg) and clozapine (1 microg), which block all dopamine receptor subtypes. The pro-erectile effect of PD-168077 was also reduced by the NO synthase inhibitor NG-nitro-L-arginine methylester (25 microg), but not by the oxytocin receptor antagonist d(CH2)5Tyr(Me)2-Orn8-vasotocin (1 microg), when given into the paraventricular nucleus. In spite of its inability to prevent the pro-erectile effect of PD-168077 when given in the paraventricular nucleus, d(CH2)5Tyr(Me)2-Orn8-vasotocin (1 microg) reduced almost completely PD-168077-induced penile erection when given into the lateral ventricles. The present results show that D4 dopamine receptors present in the paraventricular nucleus may influence penile erection by modulating the activity of paraventricular oxytocinergic neurons mediating erectile function. 相似文献
106.
Domenici MR Potenza RL Martire A Coccurello R Pèzzola A Reggio R Tebano MT Popoli P 《Journal of neuroscience research》2005,80(5):646-654
This study was designed to test whether chronic treatment with the metabotropic glutamate receptor 5 (mGlu5R) antagonist MPEP showed antiparkinsonian effects in rats unilaterally lesioned with 6-hydroxydopamine (6-OHDA) (a "classic" model of Parkinson's disease, PD), and to evaluate whether chronic MPEP influenced the functional properties and/or the expression of striatal mGlu5Rs. Wistar rats were lesioned with 6-OHDA and then treated with MPEP (3 mg/kg/day, i.p.) or its vehicle over 2 weeks. Chronic MPEP did not induce measurable antiparkinsonian effects, since no differences were found between MPEP- and vehicle-treated animals in the pattern of L-DOPA-induced contralateral rotations. In corticostriatal slices taken from animals chronically treated with MPEP, the functional effects of the mGlu5R agonist CHPG were significantly reduced in the lesioned vs. the intact side, while no changes were found in slices taken from vehicle-treated rats. The binding of [3H]MPEP to striatal membranes showed that neither the maximal number of binding sites (Bmax) nor the dissociation constant (Kd) were changed by the lesion and/or by chronic MPEP. While chronic MPEP did not potentiate L-DOPA-induced turning in a classical model of PD, its ability to reduce mGlu5R-associated signal could help to explain the neuroprotective/antiparkinsonian effects observed in other models of PD. 相似文献
107.
Comparative analysis of the neuronal activation and cardiovascular effects of nitroglycerin, sodium nitroprusside and L-arginine 总被引:1,自引:0,他引:1
In this study, we compare the biological effects, Fos expression and cardiovascular responses induced in the rat, of different nitric oxide modulators (nitroglycerin, sodium nitroprusside and L-arginine). Nitroglycerin and sodium nitroprusside induced a similar pattern of neuronal activation in several areas, which include the paraventricular and supraoptic nuclei of the hypothalamus, central nucleus of the amygdala, parabrachial nucleus, locus coeruleus, ventrolateral medulla and nucleus tractus solitarius. However, only nitroglycerin activated the periaqueductal grey and nucleus trigeminalis caudalis. L-arginine-induced neuronal activation was restricted to the paraventricular and supraoptic nuclei of the hypothalamus. As regards cardiovascular effect, both nitroglycerin and sodium nitroprusside induced moderate hypotension (nitroglycerin: -23.3%, sodium nitroprusside: -24.3%) that lasted 40 min in the case of sodium nitroprusside and 80 min in the case of nitroglycerin. L-arginine did not significantly influence blood pressure. These data suggest that nitroglycerin, sodium nitroprusside and L-arginine are associated with different biological effects on both the central nervous system and the cardiovascular system. Of the NO-related drugs tested in this study, only nitroglycerin confirmed its ability to activate brainstem areas implicated in nociception. 相似文献
108.
Lavezzi AM Ottaviani G Mingrone R Matturri L 《Brain research. Developmental brain research》2005,154(1):71-80
We investigated the immunohistochemical expression of the tyrosine hydroxylase (TH) enzyme and the morphometric parameters of the human locus coeruleus (LC) in the brainstems of 32 subjects aged from 17 gestational weeks to 12 postnatal month, died of unknown (sudden unexplained perinatal and infant deaths) and known causes. The goals of this study were: (1) to obtain basic information about the structure and physiology of the LC during the first phases of human nervous system development; (2) to evaluate whether there is altered expression of TH and/or structural alterations of the LC in cases of sudden perinatal and infant death; and (3) to verify if morphological and/or physiological abnormalities of the LC could be related to maternal cigarette smoking. Morphometric analysis showed homogeneous data in cases of sudden perinatal and infant death and in age-matched controls who had died of known aetiology. However, immunohistochemistry demonstrated in a wide subset of sudden and unexplained deaths a negativity or low positivity of TH. High distribution of TH protein were instead detectable in the LC neurons of foetuses aged 17-18 gestational weeks who had died of known causes. Therefore, we postulate the functional importance of the LC in the early phases of central nervous system development. Besides, the observation of a significant correlation between sudden unexplained death, negativity of TH staining and maternal smoking, prompted us to suppose a close relation between smoking in utero and a decrease of the noradrenergic activity of the LC, leading to sudden death in the last part of pregnancy and in the first year of life. 相似文献
109.
110.
Monaco G Montevecchi M Bonetti GA Gatto MR Checchi L 《Journal of the American Dental Association (1939)》2004,135(3):312-318
BACKGROUND: The authors conducted a study to evaluate the predictive value of five radiographic markers on the panoramic radiograph, or PR, to point out the relationship between the mandibular canal and the impacted third molar. METHODS: The authors evaluated the accuracy of the radiographic markers by comparing the PR with an axial computed tomographic, or CT, scan. They identified a sample of 73 third molars that showed a close relationship between the tooth roots and the mandibular canal on the PR, and then classified them on the basis of five radiographic markers. They also detected contact between the third molar and the mandibular canal on the CT scan. RESULTS: The distribution of the five radiographic markers was as follows: 37 teeth exhibited increased radiolucency, 13 exhibited superimposition, 14 exhibited interruption of the radiopaque border, 14 exhibited narrowing of the canal and seven exhibited diversion of the canal. In 11 cases, two or more markers were recognizable. The predictive values of a positive test result were as follows: increased radiolucency, 73 percent; superimposition, 38.5 percent; interruption of the radiopaque border, 71.4 percent; narrowing, 78.6 percent; and diversion, 100 percent. The authors detected contact in all of the cases that exhibited two or more markers. CONCLUSION: Increased radiolucency, narrowing and interruption of the radiopaque border, as well as the concomitant presence of two or more radiographic markers, on the PR were highly predictive of contact between the third molar and the mandibular canal. An axial CT scan probably is indicated in such cases. CLINICAL IMPLICATIONS: The results of this study may lead to some guidelines for oral surgeons evaluating whether to obtain an axial CT scan for further investigation after examining an impacted mandibular third molar via PR. 相似文献