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排序方式: 共有1302条查询结果,搜索用时 15 毫秒
11.
Wollmer MA Papassotiropoulos A Streffer JR Grimaldi LM Kapaki E Salani G Paraskevas GP Maddalena A de Quervain D Bieber C Umbricht D Lemke U Bosshardt S Degonda N Henke K Hegi T Jung HH Pasch T Hock C Nitsch RM 《Psychiatric genetics》2002,12(3):155-160
Tissue inhibitor of metalloproteinases 1 (TIMP-1) inhibits several proteinases including a disintegrin and metalloproteinase 10 (ADAM10), a major alpha-secretase that cleaves the beta-amyloid precursor protein within its amyloidogenic Abeta domain. The gene encoding TIMP-1 (TIMP 1) maps to the short arm of the X chromosome, in a region previously suggested as conferring genetic susceptibility for Alzheimer's disease (AD). To determine whether genetic variability of TIMP 1 contributes to the pathogenesis of AD, we analysed one single nucleotide polymorphism within TIMP 1 and one single nucleotide polymorphism in the 5'-untranslated region of TIMP 1 in patients with AD and control subjects from two independent and ethnically different populations. We did not observe any association between TIMP 1 genotypes and the diagnosis of AD in men or women. We also measured TIMP-1 protein levels in the cerebrospinal fluid of patients with AD, healthy control subjects, and patients with other neurological disorders. TIMP-1 levels were similar in all groups. In addition, no significant differences were observed after stratification for TIMP 1 genotypes. Our data show that neither genetic variability nor protein levels of TIMP-1 are associated with AD. 相似文献
12.
Fausto Sessa Daniela Furlan Anna Genasetti Paola Billo Maddalena Feltri Carlo Capella 《Diagnostic molecular pathology》2003,12(2):96-102
We studied the MSI (microsatellite instability) status and p53 expression in a series of 71 gallbladder cancers (GCs) of different histologic type. All neoplasms were examined combining a microsatellite analysis at mononucleotide locus BAT-26 and an immunohistochemical study for hMSH2, hMLH1, and p53 proteins and markers of gastric and intestinal differentiation. All the 71 GCs were MSS (microsatellite stable). The p53 protein was found in 100% of undifferentiated GCs, 67% of conventional gallbladder adenocarcinomas, 50% of mucinous adenocarcinomas, and 20% GCs with squamous differentiation. All 71 MSS tumors showed presence of immunohistochemical expression of both hMLH1 and hMSH2 gene products. We concluded that microsatellite instability does not play a role in the developing of GC while p53 seems to be the most important alteration found in a large proportion of these cancers, with the only exception of mucinous and squamous gallbladder carcinomas. 相似文献
13.
Epidemiological and Environmental Investigations of Legionella pneumophila Infection in Cattle and Case Report of Fatal Pneumonia in a Calf
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Massimo Fabbi Maddalena Castellani Pastoris Eugenio Scanziani Simone Magnino Luigi Di Matteo 《Journal of clinical microbiology》1998,36(7):1942-1947
A fatal pneumonia due to Legionella pneumophila was diagnosed in a young calf reared in a dairy herd located in northern Italy. Clinical symptoms consisted of watery diarrhea, hyperthermia, anorexia, and severe dyspnea. The pathological and histological findings were very similar to those observed in human legionellosis. Legionella pneumophila serogroup 1 (SG1) and SG10 were isolated from the calf’s lung, and L. pneumophila SG1 was isolated from the calf’s liver. L. pneumophila SG1 was also demonstrated in the lung tissue by immunofluorescence and immunohistochemical examinations. Nine of 10 L. pneumophila SG1 isolates belonged to the Olda subtype, and 1 belonged to the Camperdown subtype. A very low prevalence of antibodies to Legionella was detected in cows and calves reared in the same herd. Cultures of aqueous sediment of an old electric water heater which supplied hot water for the feeding of the calves yielded L. pneumophila SG1. Four of the colonies tested belonged to the Olda subtype. Ten clinical and four environmental isolates were examined for the presence of plasmids. Nine of them were also examined by pulsed-field gel electrophoresis assay, and the same patterns were found for L. pneumophila SG1 Olda strains isolated from the calf and from the electric heater. This is the first report of a documented case of a naturally occurring Legionella pneumonia in an animal. Cattle probably act as accidental hosts for legionellae, much the same as humans. 相似文献
14.
Panu R Bo Minelli L Botti M Gazza F Acone F Ragionieri L Palmieri G 《The anatomical record. Part A, Discoveries in molecular, cellular, and evolutionary biology》2003,275(2):1102-1108
The aim of this study was to locate in male pigs the sensory and autonomic ganglia innervating the retractor penis muscle (RPM), which was taken as an experimental model of the genital smooth musculature. The retrograde neuronal tracers horseradish peroxidase (HRP), Fast Blue (FB), and diamidino yellow (DY) were injected into the bulbopenile portion of the left RPM. The tracers highlighted a different affinity for the neuronal structures, although labelled cells supplying the RPM were generally found in bilateral dorsal root ganglia (DRGs, S1-S3), in bilateral paravertebral ganglia (PaGs, L2-S3), and in the left and right caudal mesenteric ganglia (CMGs). The mean number of labelled FB cells was 795 (range, 645-952) in DRGs, 16046.25 (range, 10226-18742) in PaGs, and 635.25 (range, 333-786) in CMGs. The mean diameter of pseudounipolar DRG cells was 60-75 microm, while the multipolar neurons of PaGs and CMGs had dimensions varying between 20-50 microm and 20-30 microm, respectively. 相似文献
15.
Paolo E. Levi-Setti Giulia Rognoni Maddalena Bozzo Guglielmo Ragusa Patrizia Sulpizio Enrico Ferrazzi Giorgio Pardi 《Journal of assisted reproduction and genetics》1995,12(7):413-417
Objectives To evaluate uterine artery resistance during multiovulation induction in relation to the implantation rate in patients attendingin vitro fertilization (IVF) cycles.Patients Multiovulation induction for IVF was monitored by daily determination of the pulsatility index (PI) of the uterine arteries, obtained by a transvaginal probe (6.5 MHz) implemented with color-flow imaging. Doppler data were obtained from 5 days before hCG administration to the day of follicular aspiration. One IVF cycle was monitored in 70 patients. In 17 patients, 41 IVF cycles were monitored until a successful attempt occurred.Results In the 70 patients studied during one IVF attempt, the PI of the uterine arteries significantly varied (P < 0.001) in the different phases of the cycle. In the 24 patients who conceived, a significantly lower PI (P < 0.03) was found throughout the cycle. This result was mainly due to a highly significant difference of PI values observed the day after hCG administration (P < 0.005). In the 17 patients who conceived after 1 to 4 negativein vitro fertilizations, no significant difference in PI was observed in the uterine artery resistance in cycles in which implantation was or was not successful.Conclusions Uterine artery resistance varies significantly during phases of the induction therapy. Uterine artery resistance is lower throughout the course of multiovulation induction in patients with higher pregnancy rates. The PI on the day after hCG administration was the best index of pregnancy rate. Low uterine artery resistance was present even in negative attempts in patients who eventually achieved a successful implantation. PI values 3 can be considered a favorable prognostic factor for future IVF cycles.Presented at the 49th Annual Meeting of the American Fertility Society, Montreal, 1993 and the 50th Annual Meeting of the American Fertility Society, November 5–10, 1994, San Antonio, Texas. 相似文献
16.
17.
Canavese C Grill A Decostanzi E Maddalena E Barbieri S Martina G Fop F Buglione E Grechi D David O Saitta M Piccoli G 《Clinical nephrology》2000,53(1):42-47
BACKGROUND: In an attempt to find new parameters able to evaluate the actual iron availability by bone marrow cells, zinc protoporphyrin (ZnPP), a metabolic intermediate generated in the red blood cell by the incorporation of zinc instead of iron, has been proposed. ZnPP is a good marker of iron-deficiency anemia in non-uremic people, as red blood cell ZnPP concentration rises specifically (except for lead intoxication) in this condition. Existing data on ZnPP as a marker of iron deficiency in uremic patients comes mainly from cross sectional studies on chronic hemodialysis and has produced conflicting results. SUBJECTS AND METHODS: Therefore, we prospectively studied 42 HID patients, 28-88 years old, 13-346 months of dialysis age, beginning from a period of maximal iron deficiency, due to the lack of parenteral iron compounds (T0) up to the end of more than one year of follow-up with continuous parenteral iron supplementation (T4). ZnPP, hemoglobin, transferrin saturation and ferritin were serially determined before and after six weeks (T1), four months (T2), seven months (T3) and 14 months (T4) of parenteral iron supplementation at a maintenance dose of 0.5-1 mg/kg/week. RESULTS: In comparison with baseline values (95+/-37 micromol/mol heme) there were no significant changes in ZnPP levels at T1 and T2 despite a continuous increase in both transferrin saturation and ferritin values, while ZnPP significantly decreased at T4 (63+/-37 micromol/mol heme, p<0.001). There was no correlation between ZnPP and both transferrin saturation and ferritin at any time during the study, the same was true for ZnPP and zinc and lead serum concentration, fibrinogen and reactive C protein levels at T1 and T4, respectively. At T4, only 2/10 patients who still showed ZnPP levels >80 micromol/mol heme had absolute or functional iron deficiency, when the percentage of hypochromic red cells were measured. CONCLUSION: We conclude that ZnPP untimely parallels a change in iron balance in only a proportion of uremic people, in as much as confounding factors, such as chronic inflammation and uremia in itself may obscure its relationship with iron status. Therefore, ZnPP cannot be assumed to be a first-line diagnostic marker of iron balance in uremic patients. 相似文献
18.
Valentina Gizzonio Pietro Avanzini Maddalena Fabbri-Destro Cristina Campi Giacomo Rizzolatti 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》2014,232(7):2381-2390
The aim of the present study was to assess the cognitive profiles of children with autistic spectrum disorder and of their healthy siblings (Siblings). With the term cognitive profile, we indicate the relationship extant among the values of verbal and performance subtests of the Wechsler Intelligence Scale. The conducted statistical analyses indicated that, although siblings showed a normal intelligent quotient and did not differ in this aspect from typically developing group, their cognitive profile was amazingly similar to that of their relatives affected by autism. A k-means clustering analysis on the values of single subtests further confirmed this result, showing a clear separation between typically developing children on the one side, and autistics and their siblings on the other. We suggest that the common cognitive profile observed in autistic children and their siblings could represent a marker of liability to autism and, thus, a possible intermediate phenotype of this syndrome. 相似文献
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20.
Adele Tessitore Miriam Patella Mauro Giuliani Thomas Theologou Stefania Freguia Eleonora Maddalena Minerva Gregor Rugel Stefano Cafarotti 《Interactive Cardiovascular and Thoracic Surgery》2021,32(3):367
We report the first surgical series of patients developing pleural empyema after severe bilateral interstitial lung disease in confirmed severe acute respiratory syndrome coronavirus 2 infection. The empyema results in a complex medical challenge that requires combination of medical therapies, mechanical ventilation and surgery. The chest drainage approach was not successful to relieve the symptomatology and to drain the excess fluid. After multidisciplinary discussion, a surgical approach was recommended. Even though decortication and pleurectomy are high-risk procedures, they must be considered as an option for pleural effusion in Coronavirus disease-positive patients. This is a life-treating condition, which can worsen the coronavirus disease manifestation and should be treated immediately to improve patient’s status and chance of recovery. 相似文献