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101.
Sara Villa Marco Vighi Antonio Finizio Graziella Bolchi Serini 《Ecotoxicology (London, England)》2000,9(4):287-297
A method for assessing the risk for honeybees from pesticide exposure via pollen is proposed. Four pesticides, selected as markers, were monitored in pollen samples collected in two sampling areas, one located in an intensive agricultural area and the other far from direct pesticide impact. Analytical results were consistent with use patterns of the chemicals and their physico-chemical and persistence properties. For a preliminary estimate of bee exposure via pollen, both by ingestion and by contact, an exposure index was developed, based on physico-chemical properties, persistence and application rates. On the basis of the exposure estimates and acute toxicological data (ingestion and contact LD50), Toxicity Exposure Ratios (TERs) were calculated as indicators of the risk for honeybees due to this particular exposure route. TER values were compared to Hazard Quotient (HQ), calculated as the ratio between application rate and the LC50 value, according to European guidelines, showing a satisfactory agreement. The advantage of the above described procedures is that the environmental fate of the chemicals, and not only application rates, are taken into account. This approach may represent a preliminary tool for a comparative screening of the risk for pollinator insects due to this particular exposure route. 相似文献
102.
Marco Gessi Emanuela Maderna Sara Guzzetti Graziella Cefalo Maura Massimino Carlo L. Solero Gaetano Finocchiaro Bianca Pollo 《Neuropathology》2008,28(6):633-639
We report a case of glioblastoma (GBM) occurring 8 years after radiation therapy for a medulloblastoma. A 15‐year‐old boy underwent surgery and radiotherapy for a medulloblastoma and 8 years later he developed a second tumor at the same site. The second lesion showed different histological and molecular features, was diagnosed as a glioblastoma and fulfilled the criteria of radiation‐induced neoplasm. Mutational analysis of the p53 gene showed a C to G transition at codon 176 in tumor DNA. LOH was detected at 17p and 19q. The tumor also showed O6‐methylguanine‐DNA methyl‐transferase (MGMT) promoter methylation and no amplification of EGF receptor. In conclusion, the radiation‐induced MGMT hyper‐methylation and p53 mutations may have a role in the development of a subgroup of radio‐induced glioma (RIG), suggesting that these molecular alterations directly cooperate in the genesis of the post‐irradiation GBM. Moreover RIGs seem to be a heterogeneous group of tumors that may resemble either primary or secondary GBM. 相似文献
103.
Gino Serra Maria Collu Paolo S. D'Aquila Graziella M. De Montis Gian Luigi Gessa 《Brain research》1990,527(2)
The effect of chronic treatment with antidepressants (ADs) on the behavioral responses to LY 171555, a selective D2 receptor agonist, SKF 38393, a selective D1 receptor agonist, and B-HT 920, a selective DA autoreceptor agonist, was studied in rats. In normal rats small, intermediate and high doses of LY 171555 produced hypomotility, hyperactivity and stereotypies, respectively. Chronic but not acute pretreatment with imipramine (IMI) greatly potentiated the motor stimulant effect of LY 171555, but failed to modify its stereotypic and sedative effect. The potentiation of the motor stimulant effect of LY 171555 was observed also after chronic, but not acute, treatment with desmethylimipramine (DMI), mianserin (MIA) or repeated electroconvulsive shock (ECS). Chronic treatment with IMI failed to modify the effect of SKF 38393 (motor stimulation, grooming and penile erection), but reversed the sedative effect of B-HT 920 into a motor stimulant response. The motor stimulant response to LY 171555 in IMI-pretreated animals was suppressed byl-sulpiride, a D2 antagonist, and by a combination of reserpine with α-methyltyrosine (α-MT), but it was only partially antagonized by high doses of SCH 23390, a selective D1 antagonist. The results indicate that chronic treatment with ADs potentiates the behavioural responses mediated by the stimulation of postsynaptic D2 receptors in the mesolimbic system and suggest that this behavioural supersensitivity is due to enhanced neurotransmission at the D1 receptor level. 相似文献
104.
Usefulness of the BACTEC MGIT 960 system for isolation of mycobacterium tuberculosis from sputa subjected to long-term storage
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Pardini M Varaine F Bonnet M Orefici G Oggioni MR;LONG-DRUG Study Group Fattorini L 《Journal of clinical microbiology》2007,45(2):575-576
The recovery of Mycobacterium tuberculosis from sputa positive or negative for acid-fast bacilli that were stored for 17 +/- 7 days and inoculated in the BACTEC MGIT 960 system (MGIT) was higher than that from sputa inoculated in Lowenstein-Jensen medium. MGIT is useful for isolation of M. tuberculosis from sputa subjected to long-term storage. 相似文献
105.
Bruno G Runzo C Cavallo-Perin P Merletti F Rivetti M Pinach S Novelli G Trovati M Cerutti F Pagano G;Piedmont Study Group for Diabetes Epidemiology 《Diabetes care》2005,28(11):2613-2619
OBJECTIVE: Incidence of type 1 diabetes is considered to be low in adults, but no study has been performed in Mediterranean countries. RESEARCH DESIGN AND METHODS: We extended the study base of the registry of the province of Turin, Italy, to subjects aged 30-49 years in the period 1999-2001 to estimate the incidences of type 1 and type 2 diabetes. Diagnosis of type 1 diabetes was based on permanent insulin treatment or a fasting C-peptide level < or =0.20 nmol/l or islet cell (ICA) or GAD (GADA) antibody positivities. RESULTS: We identified 1,135 case subjects with high completeness of ascertainment (99%), giving an incidence rate of 58.0 per 100,000 person-years (95% CI 54.7-61.5). The incidence of type 1 diabetes was 7.3 per 100,000 person-years (6.2-8.6), comparable with the rates in subjects aged 0-14 and 15-29 years (10.3 [9.5-11.2] and 6.8 [6.3-7.4]). Male subjects had a higher risk than female subjects for both type 1 (rate ratio [RR] 1.70 [95% CI 1.21-2.38]) and type 2 (2.10 [1.84-2.40]) diabetes. ICA and/or GADA positivities were found in 16% of the cohort. In logistic regression, variables independently associated with autoimmune diabetes were age 30-39 years (odds ratio [OR] 2.39 [95% CI 1.40-4.07]), fasting C-peptide <0.60 nmol/l (3.09 [1.74-5.5]), and BMI <26 kg/m2 (2.17 [1.22-3.85]). CONCLUSIONS: Risk of type 1 diabetes between age 30 and 49 years is similar to that found in the same area between age 15 and 29 years. Further studies are required to allow geographical comparisons of risks of both childhood and adulthood autoimmune diabetes, the latter being probably higher than previously believed. 相似文献
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109.
Bellan E Ferretti A Capirci C Grassetto G Gava M Chondrogiannis S Virdis G Marzola MC Massaro A Rubello D Nibale O 《Nuclear medicine communications》2012,33(5):516-520
In this paper, a new methodological approach to using PET information in radiotherapy treatment planning has been discussed. Computed tomography (CT) represents the primary modality to plan personalized radiation treatment, because it provides the basic electron density map for correct dose calculation. If PET scanning is also performed it is typically coregistered with the CT study. This operation can be executed automatically by a hybrid PET/CT scanner or, if the PET and CT imaging sets have been acquired through different equipment, by a dedicated module of the radiotherapy treatment planning system. Both approaches have some disadvantages: in the first case, the bore of a PET/CT system generally used in clinical practice often does not allow the use of certain bulky devices for patient immobilization in radiotherapy, whereas in the second case the result could be affected by limitations in window/level visualization of two different image modalities, and the displayed PET volumes can appear not to be related to the actual uptake into the patient. To overcome these problems, at our centre a specific procedure has been studied and tested in 30 patients, allowing good results of precision in the target contouring to be obtained. The process consists of segmentation of the biological target volume by a dedicated PET/CT console and its export to a dedicated radiotherapy system, where an image registration between the CT images acquired by the PET/CT scanner and a large-bore CT is performed. The planning target volume is contoured only on the large-bore CT and is used for virtual simulation, to individuate permanent skin markers on the patient. 相似文献
110.
Bruno G Merletti F Bargero G Melis D Masi I Ianni A Novelli G Pagano G Cavallo-Perin P 《Nutrition, metabolism, and cardiovascular diseases : NMCD》2008,18(1):39-45
Background and aimsIn this study we assessed the prevalence of diagnosed type 2 diabetes and the quality of care during the period 1988–2000 in an Italian population.Methods and resultsTwo population-based surveys, using similar methods and centralized measurements, were conducted in 1988 and 2000 in a representative Italian area to identify people with known diabetes. The adjusted prevalence (reference, 2001 Italian population) was computed. The age- and sex-adjusted prevalence rates of diabetes in the population of Casale Monferrato were 2.13% (2.05–2.22) in 1988 and 3.07% (2.97–3.17) in 2000. In comparison with diabetic persons recruited in 1988 and independently of age and sex, persons recruited in 2000 had a lower likelihood of having HbA1c ≥7.0% (OR = 0.48; 0.42–0.56), diastolic blood pressure ≥80 mmHg (OR = 0.61; 0.49–0.75), LDL cholesterol ≥2.59 mmol/l (OR = 0.77; 0.63–0.93) and AER ≥20 μg/min (OR = 0.53; 0.45–0.61; they had a higher likelihood of having BMI ≥25 kg/m2 (OR = 1.49; 1.2–1.74). However, 45.4% of patients still had HbA1c ≥7.0%, 80% blood pressure ≥130/80 mmHg and 79% LDL-cholesterol values ≥2.59 mmol/l.ConclusionMore than two-thirds of Italians with diabetes are now aged 65 years and more. The quality of control of glycemia, lipids and blood pressure improved and the prevalence of diabetic nephropathy decreased over time, although complete adherence to international guidelines has not yet been achieved. 相似文献