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61.
Paolo Cossu Rocca Matteo Brunelli Stefano Gobbo Albino Eccher Emma Bragantini Maria M Mina Vincenzo Ficarra Filiberto Zattoni Alberto Zamò Maurizio Pea Aldo Scarpa Marco Chilosi Fabio Menestrina Franco Bonetti John N Eble Guido Martignoni 《Modern pathology》2007,20(7):722-728
S100A1 is a calcium-binding protein, which has been recently found in renal cell neoplasms. We evaluated the diagnostic utility of immunohistochemical detection of S100A1 in 164 renal cell neoplasms. Forty-one clear cell, 32 papillary, and 51 chromophobe renal cell carcinomas, and 40 oncocytomas, 164 samples of normal renal parenchyma adjacent to the tumors and 13 fetal kidneys were analyzed. The levels of S100A1 mRNA detected by quantitative RT-PCR analysis of frozen tissues from seven clear cell, five papillary, and six chromophobe renal cell carcinomas, four oncocytomas, and nine samples of normal renal tissues adjacent to neoplasms were compared with the immunohistochemical detection of protein expression. Clear cell and papillary renal cell carcinomas showed positive reactions for S100A1 in 30 out of 41 tumors (73%) and in 30 out of 32 (94%) tumors, respectively. Thirty-seven renal oncocytomas out of 40 (93%) were positive for S100A1, whereas 48 of 51 (94%) chromophobe renal cell carcinomas were negative. S100A1 protein was detected in all samples of unaffected and fetal kidneys. S100A1 mRNA was detected by RT-PCR in all normal kidneys and renal cell neoplasms, although at very different levels. Statistical analyses comparing the different expression of S100A1 in clear cell and chromophobe renal cell carcinomas observed by immunohistochemical and RT-PCR methods showed significant values (P<0.001), such as when comparing by both techniques the different levels of S100A1 expression in chromophobe renal cell carcinomas and oncocytomas (P<0.001). Our study shows that S100A1 protein is expressed in oncocytomas, clear cell and papillary renal cell carcinomas but not in chromophobe renal cell carcinomas. Its immunodetection is potentially useful for the differential diagnosis between chromophobe renal cell carcinoma and oncocytoma. Further, S100A1 protein expression is constantly detected in the normal parenchyma of the adult and fetal kidney. 相似文献
62.
Regional effect of estradiol on rat caudate-putamen dopamine receptors: lateral-medial differences 总被引:3,自引:0,他引:3
The effect of a chronic 17 beta-estradiol (10 micrograms, b.i.d.) treatment of 2 weeks to ovariectomized rats was investigated on lateral and medial caudate-putamen dopamine receptors. Dopamine D2 receptors were assayed with [3H]spiperone binding to caudate-putamen homogenates or by autoradiography of forebrain sections. Estradiol treatment leads to a significant increase in the density of lateral caudate-putamen dopamine receptors while for the medial dopamine receptors the increase is non-significant. This effect is observed when plasma levels of 17 beta-estradiol and prolactin are increased. These results indicate that the effect of estradiol on striatal dopamine receptors is heterogeneous and that those in the lateral part are more susceptible to this steroid. 相似文献
63.
Ovariectomized rats injected with progesterone (50 micrograms s.c.) showed a peak in striatum dopamine (DA) concentration after 15 min followed by a decrease at 60-75 min and a return to control values 90 min after the steroid injection. The DA metabolites dihydroxyphenylacetic acid (DOPAC) and homovanillic acid (HVA) were increased after the progesterone injection, with a peak at 45 min and a return to control values after about 2 h. Striatum serotonin (5-HT) concentrations remained unchanged after the progesterone injection while its metabolite 5-hydroxyindoleacetic acid (5-HIAA) was increased at 45 min and returned to control values after 2 h. The peak plasma progesterone concentration occurred 15-30 min after the steroid injection while estradiol concentrations were unchanged indicating no significant conversion of progesterone into estradiol. A similar experiment was performed in male rats. As with female rats, a progesterone injection led to a progesterone peak at 30 min while plasma estradiol levels remained unchanged. Male rats responded to the progesterone injection with a maximal increase of DA, DOPAC and HVA concentrations as soon as after 15 min and these amines remained elevated up to 75 min after the steroid injection. 5-HT and 5-HIAA remained unchanged after the progesterone injection. Thus, very small physiological doses of progesterone can increase striatum dopaminergic activity in rats of both sexes while serotonergic activity is influenced only in female rats. This effect is seen within minutes and is relatively short. It is probably non-genomic, presynaptic and similar to the effect of a small dose of a DA releasing agent. 相似文献
64.
Angelo Pan Placido Mondello Klara Posfay-Barbe Patrizia Catenazzi Annise Grandi Silvia Lorenzotti Andrea Patroni Nadia Poli Laura Soavi Giuseppe Carnevale 《Infection control and hospital epidemiology》2007,28(9):1099-1102
In an Italian hospital, we observed that hand hygiene was performed in 638 (19.6%) of 3,253 opportunities, whereas gloves were worn in 538 (44.2%) 1,218 of opportunities. We observed an inverse correlation between the intensity of care and the rate of hand hygiene compliance (R2=0.057; P<.001), but no such association was observed for the rate of glove use compliance (R2=0.014; P=.078). Rates of compliance with hand hygiene and glove use recommendations follow different behavioral patterns. 相似文献
65.
Imad Sheiban M. D. Dino Casarotto Giampaolo Trevi Paolo Benussi Alberto Marini Roberto Accardi Antonio Motta Massimo Brunelli Claudio Muneretto Alessandro Tenuti Ludovico Antonio Scuro 《Cardiovascular and interventional radiology》1987,10(3):157-161
The accuracy of two-dimensional echocardiography in the detection of intracardiac masses was verified in 334 patients who
underwent cardiac catheterization in our laboratory over 21 consecutive months. A complete two-dimensional echocardiographic
(2DE) examination was performed a day before catheterization. The presence or absence of a mass was verified at surgery in
77 patients who successively underwent mitral or aortic valve replacement (51), left ventricular aneurysmectomy with or without
myocardial revascularization (25), and resection of atrial myxoma (2). In 32 patients 2DE revealed the presence of a mass-left
or right atrial thrombi in 12, left atrial myxoma in 2, left ventricular thrombi in 16, and endocardial vegetations in 2.
The other 45 patients were free of intracardiac masses on 2DE. Anatomic verification at surgery revealed the presence of an
intracardiac mass in 34 patients. In 30 (true positives) of these, 2DE revealed the mass as well, and in 4 (false negatives)
the presence of a mass had not been identified by 2DE. In 2 patients (false positives) the predicted mass was not found at
surgery. Absence of a mass was correctly predicted by 2DE in 41 patients (true negatives). Thus 2DE detected intracardiac
masses with sensitivity of 88.2% and a specificity of 95.3%. We recommend that 2DE be performed in all patients prior to hemodynamic
study and/or cardiac surgery to enable safer management of patients with intracardiac masses during cardiac catheterization
and/or cardiac surgery. 相似文献
66.
Saiidy Hasham Paolo Matteucci Paul R W Stanley Nick B Hart 《British medical journal》2005,330(7495):830-833
67.
Giuseppe Galardi Silvestro Micera Jacopo Carpaneto Silvana Scolari Massimo Gambini Paolo Dario 《Movement disorders》2003,18(11):1358-1367
We developed an automated and objective method to measure posture and voluntary movements in patients with cervical dystonia using Fastrack, an electromagnetic system consisting of a stationary transmitter station and four sensors. The junction lines between the sensors attached to the head produced geometrical figures on which the corresponding aspects of the head were superimposed. The head position in the space was reconstructed and observed from axial, sagittal, and coronal planes. Four patients with cervical dystonia and 6 healthy subjects were studied. Each patient was representative of one of the typical patterns of cervical dystonia. The study allowed the authors to collect quantitative data on posture and range of motion of the head. This pilot study demonstrates the efficacy of the Fastrack system to objectively measure the head position in cervical dystonia patients. 相似文献
68.
Marina Quartu Maria Pina Serra Annalisa Manca Paolo Follesa Rossano Ambu Marina Del Fiacco 《International journal of developmental neuroscience》2003,21(6):309-320
The immunohistochemical occurrence of the high affinity neurotrophin (NT) receptors trkA, trkB, and trkC is shown in the pre-term newborn, infant, and adult human post-mortem cerebellum. Immunoreactive neuronal perikarya and processes were observed in all specimens examined, where they appeared unevenly distributed in the cerebellar cortical layers and deep nuclei, and showed regional differences among cerebellar lobules and folia. The trk receptor-antibodies, tested by Western blot on human cerebellum homogenates, revealed multiple immunoreactive bands for trkA and single bands for trkB and trkC. The results obtained show the tissue localization of the trk receptor-like immunoreactivity in the human cerebellum from prenatal to adult age. The analysis for codistribution of the receptors with the relevant ligand and among the receptors in discrete cortical and deep nuclei tissue fields shows a wide variety of conditions, from a good similarity in terms of type and density of labeled structures, to a lack of correspondence, and suggests the possibility of colocalization of trk receptors with the relevant neurotrophin and among them in the cerebellar cortex. These results sustain the concept that the neurotrophin trophic system participates in the development, differentiation, and maintenance of the human cerebellar connectivity and support the possibility of a multifactorial trophic support for the neurotrophins through target-derived and local mechanisms. 相似文献
69.
Liliane Diefenthaeler Herter Eliete Golendziner Jos Antnio Monteiro Flores Marcelo Moretto Kristhiane Di Domenico Eduardo Becker Poli Mara Spritzer 《Journal of ultrasound in medicine》2002,21(11):1237-46; quiz 1247-8
OBJECTIVE: To describe pelvic sonographic findings in girls as old as 7 years, to compare prepubertal girls with girls who had isolated thelarche or central precocious puberty, and to verify the accuracy of sonographic variables for distinguishing prepubertal girls from girls with central precocious puberty. METHODS: Ninety-six prepubertal girls and 2 reference groups (8 girls with isolated thelarche and 8 with idiopathic central precocious puberty) were included. Ovaries were classified morphologically as homogeneous, paucicystic, macrocystic, multicystic, and having isolated cysts. Receiver operating characteristic curves were used to choose the best cutoff points. RESULTS: Chronologic and bone age were correlated with uterine length, area, and volume and ovarian volume in prepubertal girls (P < .0001). Ovarian morphologic characteristics in prepubertal girls differed significantly from those of the reference groups (P < .0001). The best cutoff points were uterine length of 4.0 cm, uterine area of 4.5 cm2, uterine volume of 3.0 cm3, and ovarian volume of 1.0 cm3. CONCLUSIONS: Uterine and ovarian growth are proportional to age in prepubertal girls. Mean ovarian volume greater than 1 cm3 showed 100% sensitivity and specificity for discriminating between prepubertal girls and girls with central precocious puberty. Microcysts are common in prepubertal girls, but the presence of 6 or more follicles up to 10 mm in diameter may suggest central precocious puberty in girls younger than 8 years. 相似文献
70.