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41.
42.
Ultrastructural analysis of pancreatic acinar cells from mice fed on genetically modified soybean 下载免费PDF全文
Malatesta M Caporaloni C Rossi L Battistelli S Rocchi MB Tonucci F Gazzanelli G 《Journal of anatomy》2002,201(5):409-415
No direct evidence that genetically modified (GM) food may represent a possible danger for health has been reported so far; however, the scientific literature in this field is quite poor. Therefore, we investigated the possible effects of a diet containing GM soybean on mouse exocrine pancreas by means of ultrastructural, morphometrical and immunocytochemical analyses. Our observations demonstrate that, although no structural modification occurs in pancreatic acinar cells of mice fed on GM soybean, quantitative changes of some cellular constituents take place in comparison to control animals. In particular, a diet containing significant amount of GM food seems to influence the zymogen synthesis and processing. 相似文献
43.
Crotti D D'Annibale ML Ubaldi M Fonzo G Medori MC 《Le infezioni in medicina : rivista periodica di eziologia, epidemiologia, diagnostica, clinica e terapia delle patologie infettive》2002,10(4):213-219
During 2001 we analyzed 1730 pharyngeal swabs for S. pyogenes (SGA): 1142 children (0-10 years old), 132 adolescent subjects (11-17 years old), and 456 adults (18 or more years old). 994 subjects (664 children, 85 adolescent ones, 245 adults) had acute pharyngotonsillitis. In this last group we observed 321 positivities (32.3 %) for SGA: 40.4 % among children, 24.7 % among adolescent people, 13.1 % among adults. The pharyngotonsillitis prevailed during winter and spring. The resistances (R) towards erythromycin were 27.7 % (89 cases), and among children 30.6 % (82 cases), towards clyndamicin 15.3 % (49 cases, and 17.2 %, 46 cases, among children), towards rokytamicin 11.8 % (38 cases, and 13.1 %, 35 cases, among children). These were the phenotypes of R to erythromycin: 25.8 % M-phenotype, 19.1 % inducible (iMLS), 55.1 % constitutive (cMLS); among children respectively 25.6 %, 18.3 % and 53.7 %. Increased resistances towards 16-C macrolides, increased resistances of cMLS to erythromycin, and the persistence of R to 14-C macrolides around 30 % are discussed. 相似文献
44.
Cutaneous mucormycosis in a young, immunocompetent girl. 总被引:2,自引:0,他引:2
Manoel Paes de Oliveira-Neto Manuela Da Silva Paulo Cezar Fialho Monteiro Márcia Lazera Rodrigo de Almeida Paes Anna Beatriz Novellino Tulia Cuzzi 《Medical mycology》2006,44(6):567-570
We report a case of cutaneous mucormycosis in a healthy, immunocompetent young girl (age 14 years). The patient had a 5-year history of a slowly enlarging, erythematous plaque with slight elevated, scaling, circinate borders on the right thigh. Histopathology showed a granulomatous infiltrate with broad, pale, non-septate hyphae. Mycological study identified Mucor hiemalis (Wehmer). 相似文献
45.
Pietro Maria Donisi Nadia Di Lorenzo Manuela Riccardi Alessandro Paparella Claudia Sarpellon Simona Zupo Giovanni Bertoldero Claudia Minotto Vincenzo Stracca-Pansa 《Diagnostic molecular pathology》2006,15(4):206-215
We analyzed individual VH gene rearrangements in 55 consecutive B-chronic lymphocytic leukemia (B-CLL) patients collected from a northeastern region of Italy, stressing the possible differences related to geographic characteristics of the cohorts studied. Considering the percentage of somatic mutations present in the VH gene sequences and using the 98% cut-off value, 38 of the 55 B-CLL (69%) patients displayed somatic hypermutations and 17 (31%) had a germline configuration. Our results confirm and extend the observations of a bias in the use of certain VH, DH, and JH genes among B-CLL cells. The most frequently used VH genes were VH1-69 (12.7%) with VH3-23 (12.7%) and VH4-34 (10.9%). Collectively these genes accounted for 36.3% of the cases. In the mutated cases, the range of mutations varied from 2% to 15%, with a median of 6.5%. VH1-69 (7 cases, all unmutated) carried few mutations as opposed to VH3-23 (7 cases, 5 of which mutated), VH4-34 (6 cases, all mutated), and VH3-30 (5 cases, all mutated), which show a high load of mutations. D3 family genes were found frequently (38.1%) followed by D2 (27.2%) and D6 (18.1%). The individual D segment most frequently used was D3-3, which was present in 16.3% of cases. There was predominance of the JH4 gene (49%) followed by JH6 (40%). Analysis of the distribution of replacement and silent mutations in the mutated sequences using the method of Lossos showed in 39.4% of cases evidence of antigen selection in the framework region and/or complementary determining regions. In comparison with a recent study on B-CLL patients from the Mediterranean area, the VH4-34 gene was significantly overused in the mutated group at a percentage double that of the Italian cohort reported in this study (10.9% vs. 5%), but at a frequency similar to the entire Mediterranean region (10.7%). We also found an over-representation of VH1-69 usage in the germline group, at a frequency (12.7%) higher than previously described by the same authors (Italian 8%, Mediterranean 10.7%). On the contrary, VH3-07 and VH3-49 were not much used in our study (5.4% and 1.8%, respectively) compared with the Italian group (8% and 5.1%). In our study, VH3-23 gene segment was frequently expressed, at frequency as high as that of VH1-69, a finding in keeping with reported B-CLL Italian data, but higher than the entire series of the Mediterranean area (12.7% vs. 9.2%); VH3-21 gene, frequently expressed in northern European CLL but rarely in the Mediterranean area, was completely absent. This biased usage of VH family genes may reflect a geographic leukemic repertoire, perhaps owing to a peculiar genetic background, depending on variations in germline composition of the IgVH locus or to the effect of a potential environmental element less frequently encountered in different regions. 相似文献
46.
A MicroRNA signature associated with prognosis and progression in chronic lymphocytic leukemia 总被引:2,自引:0,他引:2
47.
Foxl2 disruption causes mouse ovarian failure by pervasive blockage of follicle development 总被引:6,自引:0,他引:6
Uda M Ottolenghi C Crisponi L Garcia JE Deiana M Kimber W Forabosco A Cao A Schlessinger D Pilia G 《Human molecular genetics》2004,13(11):1171-1181
FOXL2 mutations cause gonadal dysgenesis or premature ovarian failure (POF) in women, as well as eyelid/forehead dysmorphology in both sexes (the 'blepharophimosis-ptosis-epicanthus inversus syndrome', BPES). Here we report that mice lacking Foxl2 recapitulate relevant features of human BPES: males and females are small and show distinctive craniofacial morphology with upper eyelids absent. Furthermore, in mice as in humans, sterility is confined to females. Features of Foxl2 null animals point toward a new mechanism of POF, with all major somatic cell lineages failing to develop around growing oocytes from the time of primordial follicle formation. Foxl2 disruption thus provides a model for histogenesis and reproductive competence of the ovary. 相似文献
48.
Mancuso M Conforti FL Rocchi A Tessitore A Muglia M Tedeschi G Panza D Monsurrò M Sola P Mandrioli J Choub A DelCorona A Manca ML Mazzei R Sprovieri T Filosto M Salviati A Valentino P Bono F Caracciolo M Simone IL La Bella V Majorana G Siciliano G Murri L Quattrone A 《Neuroscience letters》2004,371(2-3):158-162
Mitochondrial impairment has been implicated in the pathogenesis of the amyotrophic lateral sclerosis (ALS). Furthermore, mitochondrial-specific polymorphisms were previously related to other neurodegenerative diseases, such as Parkinson, Friedreich and Alzheimer disease. To investigate if specific genetic polymorphisms within the mitochondrial genome (mtDNA) could act as susceptibility factors and contribute to the clinical expression of sporadic ALS (sALS), we have genotyped predefined European mtDNA haplogroups in 222 Italian patients with sALS and 151 matched controls. Individuals classified as haplogroup I demonstrated a significant decrease in risk of ALS versus individuals carrying the most common haplogroup, H (odds ratio 0.08, 95% confidence interval 0.04-0.4, p < 0.01). Further stratification of the dataset by sex, age and site of onset of disease and survival failed to reach significance for association. Our study provides evidence of the contribution of mitochondrial variation to the risk of ALS development in Caucasians. Further it may help elucidate the mechanism of the mitochondrial dysfunction detectable in ALS, and may be of relevance in development of strategies for the treatment of this disease. 相似文献
49.
Flight S Johnson L Trabi M Gaffney P Lavin M de Jersey J Masci P 《Pathophysiology of haemostasis and thrombosis》2005,34(4-5):188-193
Textilinin-1 (Q8008) was isolated from the venom of the Pseudonaja textilis and has a 47% sequence identity to the antihaemorrhagic therapeutic agent aprotinin. When equimolar concentrations of enzyme and aprotinin were pre-incubated, plasmin was inhibited 100%, plasma kallikrein 58%, and tissue kallikrein 99%. Under the same conditions, textilinin-1 inhibited plasmin 98%, plasma kallikrein 16% and tissue kallikrein 17%. Whole blood clot lysis was inhibited strongly by both aprotinin and textilinin-1, as shown by thrombelastography. At 2 microM inhibitor lysis initiated by t-PA was greater than 99% inhibited by aprotinin (LY60 = 0.4 +/- 0.1) whereas textilinin-1, inhibited lysis by 91% (LY60 = 8.9 +/- 0.7). The same trend was found with the lysis of euglobulin fractions. From these data textilinin-1 appears to be a more specific plasmin inhibitor than aprotinin but aprotinin inhibits clot lysis to a greater extent. 相似文献
50.
Indolent systemic mastocytosis with elevated serum tryptase, absence of skin lesions, and recurrent severe anaphylactoid episodes 总被引:2,自引:0,他引:2
Florian S Krauth MT Simonitsch-Klupp I Sperr WR Fritsche-Polanz R Sonneck K Födinger M Agis H Böhm A Wimazal F Horny HP Valent P 《International archives of allergy and immunology》2005,136(3):273-280
BACKGROUND: In contrast to aggressive mastocytosis, patients with indolent systemic mastocytosis (ISM) usually present with urticaria pigmentosa-like skin lesions. In those who lack skin lesions, mastocytosis is often overlooked or confused with endocrinologic, allergic, or other internal disorders. CASE REPORT AND RESULTS: We report on a 33-year-old male patient in whom severe hypotensive episodes occurred after contact with ants or yellow jackets. Since no specific IgE was detected, the serum tryptase concentration was measured and found to be clearly elevated (70 ng/ml). Consecutive staging and examination of the bone marrow revealed ISM. The patient was advised to circumvent insect contact, to take antihistamines on demand, and to carry an epinephrine self-injector for emergency events. In a retrospective analysis of 40 patients seen between 1988 and 2003, only 2 had a life-threatening mediator-related episode before ISM was diagnosed. CONCLUSIONS: Our report confirms the diagnostic value of tryptase in patients with suspected mastocytosis. In addition, the report suggests that the lack of typical skin lesions does not exclude an indolent form of mastocytosis even if the serum tryptase is clearly elevated. Finally, our case further shows that mastocytosis can be an important differential diagnosis to be considered in patients with unexplained anaphylactoid or other mediator-related symptoms. 相似文献