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51.
G. Bersani A. Quartini G. Manuali A. Iannitelli D. Pucci F. Conforti C. Di Biasi G. Gualdi 《Neuroradiology》2009,51(6):363-371
Introduction The purpose of this study was to determine if a causal relationship exists between obstetric complications (OCs) severity
and linear magnetic resonance (MR) measurements of brain atrophy in patients with schizophrenia.
Materials and methods Linear measurements of ventricular enlargement (bifrontal span, Evans ratio, and bicaudate ratio) and hippocampal atrophy
(interuncal distance) were completed on MR images obtained in 47 patients with schizophrenia. Regression analysis was used
to look at association with OCs severity, assessed by the “Midwife protocol” of Parnas and colleagues. The relationship between
MR measurements and phenomenologic variables such as age at onset, illness duration, and exposure to antipsychotic medications
was explored. The relationship between MR measurements, OCs severity, and symptom presentation was also investigated.
Results OCs severity was significantly associated with MR measurements of ventricular enlargement (bifrontal span, Evans ratio). As
the severity of OCs increased, bifrontal span and Evans ratio increased. This effect was independent of age at onset, illness
duration, or even antipsychotic treatment. Interestingly, bifrontal span, Evans ratio, and OCs severity score all showed a
significant positive correlation with hallucinatory symptomatology.
Conclusion Although confirmatory studies are needed, our findings would support the idea that environmental factors, in this case severe
OCs, might partly contribute to ventricular abnormalities in schizophrenia. 相似文献
52.
Connor NP Conforti ML Heisey DM Vanderby R Kunz D Hartig GK 《Journal of rehabilitation research and development》2002,39(4):505-512
Reconstructive microsurgery is performed to reattach, transfer, or transplant body tissues. Venous congestion is a complication that threatens the viability of the affected tissue and is often treated with medicinal leeches. Leech therapy has two phases: active bloodletting and passive bleeding from the leech wound after detachment, which can last for several hours. Unfortunately, the small blood volumes removed by medicinal leeches are generally ineffective in decongesting tissue. Our goal was to develop a device to augment blood removal during the passive-bleeding phase of leech therapy with the use of a porcine model of venous congestion. Results indicated that the use of the device resulted in significant increases in blood retrieval relative to reports of passive bleeding alone (141%, 156%, and 155% in 1, 2, and 3 hours, respectively). These results are an encouraging first step toward development of a mechanical device that completely replaces the use of medicinal leeches in modern medicine. 相似文献
53.
Adverse drug reactions related to amoxicillin alone and in association with clavulanic acid: data from spontaneous reporting in Italy 总被引:1,自引:0,他引:1
Salvo F Polimeni G Moretti U Conforti A Leone R Leoni O Motola D Dusi G Caputi AP 《The Journal of antimicrobial chemotherapy》2007,60(1):121-126
OBJECTIVES: To analyse an Italian database of spontaneous reporting of suspected adverse drug reactions in order to compare the safety profile of amoxicillin and amoxicillin/clavulanic acid. METHODS: Data were retrieved from the spontaneous reports collected by six Italian regions (the GIF database) from January 1988 to June 2005. Drug utilization data were also available for the two drugs. The comparison between amoxicillin and amoxicillin/clavulanic acid was made using the chi(2) or Student's t-test, when appropriate. Disproportionality in reporting of adverse events was assessed using reporting odds ratio methodology. RESULTS: Up to June 2005, the GIF database collected 37 906 reports, of which 1088 were related to amoxicillin/clavulanic acid and 1095 to amoxicillin. The percentage of skin reactions was statistically higher for amoxicillin (82%) than for amoxicillin/clavulanic acid (76%); on the contrary, the percentage of gastrointestinal, hepatic and haematological reactions was significantly higher for amoxicillin/clavulanic acid (13%, 4% and 2%, respectively) than for amoxicillin (7%, 1% and 1%, respectively). Amoxicillin/clavulanic acid seems to be associated with a higher risk of Stevens-Johnson syndrome, purpura and hepatitis than amoxicillin alone. In particular, the reporting rate of hepatitis is on average 9-fold higher for amoxicillin/clavulanic acid than for amoxicillin. CONCLUSIONS: Analysis shows a different safety profile for the two selected drugs. The combination of amoxicillin/clavulanic acid has been increasingly used in Italy and now represents the most frequently antibiotic prescribed by Italian general practitioners. Given the documented level of inappropriate use of beta-lactams in Italy, these results should be taken into account by physicians before prescribing amoxicillin/clavulanic acid to patients. 相似文献
54.
Nitric oxide (NO) is a diatomic free radical produced from L-arginine by constitutive and inducible nitric oxide synthase (cNOS and iNOS) in numerous mammalian cells and tissues. Nitric oxide (NO), superoxide (O2-) and their reaction product peroxynitrite (ONOO-) may be generated in excess during the host response against viral and antibacterial infections and contribute to some pathogenesis by promoting oxidative stress, tissue injury and, even, cancer. Oxidative damage, caused by action of free radicals, may initiate and promote the progression of a number of chronic diseases, including cancer, cardiovascular diseases, Alzheimer's disease, diabetes and inflammation. The mechanism of inflammation injury is attributed, in part, to release of reactive oxygen species from activated neutrophils and macrophages. ROS propagate inflammation by stimulating release of mediators such as NO and cytokines. The interest of the research is motivated by the current need to find new substances of natural origin which have demonstrated effectiveness in the described fields of application and low degree of toxicity for humans. Natural products provide a vast pool of NO inhibitors that can possibly be developed into clinical products. This article reviews some plenolic secondary metabolites from plants with NO inhibitory properties and their structure-activity relationship studies that can be focused for drug development programs. 相似文献
55.
Bartoli F Angotti C Fatini C Conforti ML Guiducci S Blagojevic J Melchiorre D Fiori G Generini S Damjanov N Rednic S Pignone A Castellani S Abbate R Matucci Cerinic M 《Rheumatology (Oxford, England)》2007,46(5):772-775
OBJECTIVE: Systemic sclerosis (SSc) is characterized by microvascular and macrovascular alterations. The D allele of the ACE I/D polymorphism is known to be associated with an increased incidence of atherosclerosis and has been recently proposed as associated with increased risk of SSc. This study evaluates the relationship between intima-media thickness (IMT), ankle-brachial pressure measurements (ABPI) and ACE I/D polymorphism in SSc patients. METHODS: According to the presence of ACE D allele (analysed by PCR), 53 SSc patients (47 females and 6 males; median age was 60.4 +/- 10.68 yrs; range 40-75 yrs) were divided in carriers of the D allele (DD + ID) (n = 46) and carriers of the I allele (II) (n = 7). In these patients, IMT and ABPI [calculated as the posterior tibial artery pressure (mmHg) divided by the brachial pressure] were obtained. Forty-three healthy controls (40 women and 13 men; median age 56.3 +/- 10.23; range 40-70 yrs) of the same ethnicity were recruited. RESULTS: SSc patients had IMT significantly higher than controls (0.85 +/- 0.03 vs 0. 68 +/- 0.01; P < 0.03). No significant differences (P > 0.3) in ABPI values between patients (1.018 +/- 0.10) and controls (1.091 +/- 0.11) were found. SSc patients with ACE DD and ID genotype showed an IMT significantly greater (0.89 +/- 0.03) than those carrying the II genotype (0.61 +/- 0.01) (P < 0.04). ABPI was not different among ACE gene genotypes. CONCLUSION: Our findings confirm an increased prevalence of macrovascular disease in SSc patients and show that IMT is greater in patients carrying the ACE DD and ID genotype in comparison with II homozygotes. This suggests that, in SSc, the presence of ACE D allele may predispose to an involvement of the macrovascular system. 相似文献
56.
Neurodegenerative disorders involve death of cell bodies, axons, dendrites and synapses, but it is surprisingly difficult to determine the spatiotemporal sequence of events and the causal relationships among these events. Neuronal compartments often crucially depend upon one another for survival, and molecular defects in one compartment can trigger cellular degeneration in distant parts of the neuron. Here, we consider the novel approaches used to understand these biologically complex and technically challenging questions in amyotrophic lateral sclerosis, spinal muscular atrophy, glaucoma, Alzheimer's disease, Parkinson's disease and polyglutamine disorders. We conclude that there is partial understanding of what degenerates first and why, but that controversy remains the rule not the exception. Finally, we highlight strategies for resolving these fundamental issues. 相似文献
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