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141.
The authors report a case of mutism that was ultimately found to be associated with chronic cocaine use in an adult woman. Brain dysfunction was confirmed by SPECT scan, which revealed reduced cerebral blood perfusion and areas of infarction, presumably consequent to the cocaine addiction. This is the first reported case of such an association. 相似文献
142.
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
143.
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
144.
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
145.
146.
Evaluation and treatment of secondary tricuspid insufficiency. 总被引:1,自引:0,他引:1
A Pellegrini T Colombo F Donatelli M Lanfranchi E Quaini C Russo E Vitali 《European journal of cardio-thoracic surgery》1992,6(6):288-296
To define the role of functional tricuspid insufficiency and right ventricular (RV) failure in patients with mitral disease, the data of 121 patients with secondary tricuspid insufficiency that underwent mitral valve replacement (MVR) from January 1982 to December 1987 were analyzed. The mitral hemodynamic lesion was: stenosis in 41 patients (33.9%); insufficiency in 11 (9.1%) and mixed stenosis and insufficiency in 69 (57.0%). NYHA functional class was: II in 4 patients (3.3%), III in 78 (64.5%) and IV in 39 (32.2%). In 100 cases (group 1) with tricuspid insufficiency defined as moderate or severe, a De Vega annuloplasty was performed while in 21 (group 2) with mild tricuspid insufficiency, no tricuspid surgical procedure was performed. Hospital deaths occurred in 17 of 121 patients [14% (CL 10.8-17.0)]. There was no significant difference in hospital mortality between group 1 and group 2 (15% vs 9.5%; P = 0.75). Incremental risk factors for hospital mortality as determined by multivariate analysis, include: cardiothoracic ratio (P = 0.0016), total aortic cross-clamp time (P = 0.006), associated cardiac disease (P = 0.0209) and emergency operations (P = 0.0318). Mean follow-up of surviving patients was 50.1 +/- 28.1 months. Late deaths occurred in 16 patients [15.4% (CL 11.7-18.7)]. The actuarial survival rate was 85.6% and 73.8% at 5 and 9 years, respectively. Nine patients [8.6% (CL 5.9-11.3)] required reoperation. There was no significant difference between group 1 and group 2 in the rate of late cardiac related deaths (5.9% vs 5.3%, P = 0.66) and of tricuspid reoperations (4.7% vs 5.3%, P = 0.62).(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
147.
Usefulness of the BACTEC MGIT 960 system for isolation of mycobacterium tuberculosis from sputa subjected to long-term storage 下载免费PDF全文
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
148.
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
149.
The 1999-2000 avian influenza (H7N1) epidemic in Italy: veterinary and human health implications 总被引:3,自引:0,他引:3
From the end of March to the beginning of December 1999, 199 outbreaks of low pathogenicity avian influenza (LPAI) were diagnosed in the Veneto and Lombardia regions, which are located in the northern part of Italy. The virus responsible for the epidemic was characterized as a type A influenza virus of the H7N1 subtype of low pathogenicity. On the 17th of December, highly pathogenic avian influenza (HPAI) was diagnosed in a meat turkey flock in which 100% mortality was observed in 72 h. The infection spread to the industrial poultry population of northern Italy including chickens, guinea-fowl, quail, pheasants, ducks and ostriches for a total of 413 outbreaks. Over 13 million birds were affected by the epidemic, which caused dramatic economic losses to the Italian poultry industry with severe social and economic implications. The possibility of H7 virus transmission to humans in close contact with the outbreaks was evaluated through a serological survey. Seven hundred and fifty nine sera were collected and tested for the detection of anti-H7 antibodies by means of the micro-neutralization (MN) and single radial haemolysis (SRH) tests. All samples resulted negative. A limited number of clinical samples were also collected for attempted virus isolation with negative results. Current European legislation considers LPAI and HPAI as two completely distinct diseases, not contemplating any compulsory eradication policy for LPAI and requiring eradication for HPAI. Evidence collected during the Italian 1999-2000 epidemic indicates that LPAI due to viruses of the H7 subtype may mutate to HPAI, and, therefore, LPAI caused by viruses of the H5 or H7 subtypes must be controlled to avoid the emergence of HPAI. A reconsideration of the current definition of avian influenza adopted by the EU, could possibly be an aid to avoiding devastating epidemics for the poultry industry in Member States. 相似文献