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排序方式: 共有1037条查询结果,搜索用时 15 毫秒
1.
Rolando Barbucci Mario Casolaro Mila Nocentini Gianna Reginato Paolo Ferruti 《Macromolecular chemistry and physics.》1986,187(8):1953-1962
Two linear vinyl polymers carrying amido and primary amino groups in the side chains were synthesized and characterized. Their behaviour in aqueous solution was investigated by potentiometric, viscometric and calorimetric techniques. In both cases, the basicity constants show a linear dependence on the degree of protonation α, while the enthalpy values of protonation do not. The thermodynamic results demonstrate the important role of hydrophobic interactions on the protonation process. 相似文献
2.
Antinori Andrea Cingolani Antonella Lorenzini Patrizia Giancola Maria Letizia Uccella Ilaria Bossolasco Simona Grisetti Susanna Moretti Francesca Vigo Beniamino Bongiovanni Marco Del Grosso Bruno Arcidiacono Maria Irene Fibbia Giovanni Carlo Mena Maurizio Finazzi Maria Grazia Guaraldi Giovanni Ammassari Adriana Monforte Antonella dArminio Cinque Paola De Luca Andrea 《Journal of neurovirology》2003,9(1):47-53
Human immunodeficiency virus (HIV)-associated progressive multifocal leukoencephalopathy (PML) remains a relevant clinical problem even in the era of highly active antiretroviral therapy (HAART). Aims of the study were to analyze clinical and treatment-related features and the survival probability of PML patients observed within the Italian Registry Investigative Neuro AIDS (IRINA) during a 29-month period of HAART. Intravenous drug use, the presence of focal signs, and the involvement of white matter at neuroradiology increased the risk of having PML. A reduced probability of PML was observed when meningeal signs were reported. Patients starting HAART at PML diagnosis and previously naïve for antiretrovirals showed significantly higher 1-year probability of survival (.58), compared to those continuing HAART (.24), or never receiving HAART (.00). Higher CD4 cell count were associated with a higher survival probability (.45). At multivariate analysis, a younger age, higher CD4, starting HAART at PML diagnosis, the absence of previous acquired immunodeficiency syndrome (AIDS)-defining events, and the absence of a severe neurologic impairment were all associated with a reduced hazard of death. The use of cidofovir showed a trend towards a reduced risk of death. 相似文献
3.
Malignant myoepitheliomas are rare tumors of salivary glands. Most occur in the parotid gland; few other sites of origin are described. Malignant myoepithelioma of the rhinopharynx has only been reported twice. Because the lesion is so rare, there are no specific indications for its treatment. We present a third case of malignant myoepithelioma in the rhinopharynx and discuss its diagnostic and therapeutic aspects. 相似文献
4.
5.
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
6.
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
7.
Inducible nitric oxide synthase expression in human colorectal cancer: correlation with tumor angiogenesis 总被引:15,自引:0,他引:15 下载免费PDF全文
Cianchi F Cortesini C Fantappiè O Messerini L Schiavone N Vannacci A Nistri S Sardi I Baroni G Marzocca C Perna F Mazzanti R Bechi P Masini E 《The American journal of pathology》2003,162(3):793-801
To investigate the potential involvement of the nitric oxide (NO) pathway in colorectal carcinogenesis, we correlated the expression and the activity of inducible nitric oxide synthase (iNOS) with the degree of tumor angiogenesis in human colorectal cancer. Tumor samples and adjacent normal mucosa were obtained from 46 surgical specimens. Immunohistochemical expression of iNOS, vascular endothelial growth factor (VEGF), and CD31 was analyzed on paraffin-embedded tissue sections. iNOS activity and cyclic GMP levels were assessed by specific biochemical assays. iNOS protein expression was determined by Western blot analysis. iNOS and VEGF mRNA levels were evaluated using Northern blot analysis. Both iNOS and VEGF expressions correlated significantly with intratumor microvessel density (r(s) = 0.31, P = 0.02 and r(s) = 0.67, P < 0.0001, respectively). A significant correlation was also found between iNOS and VEGF expression (P = 0.001). iNOS activity and cyclic GMP production were significantly higher in the cancer specimens than in the normal mucosa (P < 0.0001 and P < 0.0001, respectively), as well as in metastatic tumors than in nonmetastatic ones (P = 0.002 and P = 0.04, respectively). Western and Northern blot analyses confirmed the up-regulation of the iNOS protein and gene in the tumor specimens as compared with normal mucosa. NO seems to play a role in colorectal cancer growth by promoting tumor angiogenesis. 相似文献
8.
Eye movements induced by lateral acceleration steps
Effect of visual context and acceleration levels
C. C. Gianna Michael A. Gresty Adolfo M. Bronstein 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1997,114(1):124-129
Eye movement responses were obtained from six normal subjects exposed to randomly ordered rightwards/leftwards linear acceleration
steps of 0.05 g, 0.1 g or 0.24 g amplitude and 650 ms duration along the inter-aural axis. With the instruction to gaze passively into the darkness, compensatory nystagmus was evoked with slow-phase velocity sensitivity of 49° s−1
g
−1. When subjects viewed earth-fixed targets at 30 cm, 60 cm or 280 cm, eye movements at 130 ms from motion onset were proportional to acceleration and inversely proportional
to target distance, before the onset of visually guided eye movements. Our results show that a modulation with viewing distances
of the earliest human otolith-ocular reflexes occurs in the presence of pure linear acceleration. However, full compensation
was not attained for the nearer targets and higher accelerations.
Received: 31 January 1996 / Accepted: 30 September 1996 相似文献
9.
Tozzi V Balestra P Galgani S Narciso P Sampaolesi A Antinori A Giulianelli M Serraino D Ippolito G 《Journal of acquired immune deficiency syndromes (1999)》2001,28(1):19-27
OBJECTIVES: To describe changes in HIV-associated neurocognitive impairment in patients treated with highly active antiretroviral therapy (HAART) for at least 3 years. METHODS: Prospective, observational study of comprehensive neuropsychologic (NP) testing, neurologic examination, and laboratory measures before HAART and after 6, 15 and 45 months of HAART, on 28 consecutive patients seen in our department since April 1996. RESULTS: At baseline, 16 patients were neurocognitively impaired and 12 were not. Among the 16 impaired patients, 5 patients failed to meet the criteria for impairment after 6 months and 9 patients after both 15 and 45 months of HAART, respectively. Statistically significant improvements ( p < or =.01) were seen in two of six measures exploring the concentration and speed of mental processing, two of three measures exploring mental flexibility, in one of five measures exploring memory, and in two of two measures exploring fine motor functions. Unimpaired study subjects performed better than impaired ones in 10 of 17 measures at baseline, in eight of 17 after 6 months, in six of 17 after 15 months, and in seven of 17 after 45 months of HAART. CONCLUSIONS: During the course of HAART, patients experienced a positive and sustained improvement in their neurocognitive performance. However, the presence of 7 of 16 (43.7%) patients with neurocognitive impairment, and the persistence of statistically significant differences in the neurocognitive performance between impaired and unimpaired patients after more than 3 years of HAART, suggests that ongoing HIV-related neurologic damage can occur even during potent antiretroviral treatment. 相似文献
10.
Guido Monga Gianna Mazzucco Francesco Paolo Rossini Franco Presti 《Virchows Archiv : an international journal of pathology》1979,382(3):355-360
Summary An unusual form of colorectal polyposis is described displaying juvenile, adenomatous and mixed patterns in a 17-year-old girl. Although juvenile polyposis is generally considered to be non-neoplastic in nature, in both the present and in other case reports histological findings support a neoplastic nature. Since an increase in the incidence of large bowel carcinomas has been found in subjects with a previous diagnosis of juvenile polyposis, these patients should be considered to be at risk, and submitted to follow up. 相似文献