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21.
22.
Walter Devoto Davide Pansecchi 《Practical procedures & aesthetic dentistry》2007,19(8):465-70; quiz 472, 501
Composite resin has proven to be a predictable and reliable restorative material for the treatment of traumatized dentin or dental caries in the anterior region. Ongoing material advancements continue to contribute to favorable results in the treatment of the contemporary patient. In using a resin material, it is important for the dental professional to establish an appropriate clinical approach that will protect healthy tissues, while meeting the patient's expectations. This article presents a series of cases that encompass the clinical and aesthetic possibilities provided by modern composites. LEARNING OBJECTIVES: This article depicts the potential clinical and aesthetic results that can be achieved using contemporary composite resins. Upon reading this article, the reader should: 1) Understand operative techniques for obtaining aesthetic results in the anterior maxilla. 2) Become familiar with the importance of formulating a treatment strategy that combines minimum chairtime with a high-quality, aesthetic result. 相似文献
23.
Emanuele Lezoche M.D. Alessandro M. Paganini M.D. Ph.D. Francesco Carlei M.D. Francesco Feliciotti M.D. Davide Lomanto M.D. Ph.D. Mario Guerrieri M.D. 《World journal of surgery》1996,20(5):535-542
n
= 2), port site infection (
n
= 2), and subumbilical hematoma (
n
= 1). Major morbidity was bile leakage from the cystic duct stump in two cases due to clips or transcystic duct drainage displacement,
respectively. One elderly, high risk patient died after being referred for several failed attempts of endoscopic clearance;
she died from cardiogenic shock 3 days after successful laparoscopic treatment. Laparoscopic CBD exploration is feasible and
safe in most patients, with short-term results that compare favorably with the results of sequential ES/LC reported in the
literature. 相似文献
24.
Francesco Ferrozzi Davide Bova Fabio Campodonico 《Seminars in Ultrasound, CT and MRI》1997,18(2):115-121
Since the advent of CT, secondary neoplastic lesions of the kidneys have been detected with increasing frequency. After reviewing a large series of cases of renal metastases, we have been able to classify the CT findings into seven major categories that are discussed and illustrated in this article. The differential diagnoses between metastatic disease of the kidneys and other lesions such as renal infarctions, renal lymphoma, and primary malignancies are also considered. 相似文献
25.
Angelo Sghirlanzoni Davide Pareyson Claudio Benvenuti Giovanni Cei Vittorio Cosi Mariella Lombardi Mariaflavia Nicora Roberta Ricciardi Ferdinando Cornelio 《Journal of neurology》1992,239(3):165-169
Summary The efficacy of intranasally administered neostigmine was tested in 22 patients with generalized myasthenia gravis (MG). Topical therapy to the highly vascularized oropharynx proved to be quickly effective in 5–15 min both clinically and electrophysiologically. Twenty-eight MG patients were then recruited from different centres and their morning doses of oral pyridostigmine were substituted with intranasal neostigmine over a period of 2 or 3 weeks. Intranasal neostigmine proved to be equally efficacious in this regimen. No side-effect was noted even in 4 patients treated in this way for 1 year. Intranasal administration of anti-acetylcholinesterase may be very beneficial: (1) for patients with irregular absorption of oral doses; (2) early in the morning and every time a fast and temporary effect is needed; (3) in bulbar impairment and emergencies, in which a handy atomizer may be life-saving.Presented in part at the XIV World Congress of Neurology, New Delhi, 22–27 October 1989 相似文献
26.
Raffaella Marazzi Davide Pareyson Amerigo Boiardi Massimo Corbo Vidmer Scaioli Angelo Sghirlanzoni 《Journal of neurology》1992,239(6):317-321
Summary Peripheral neuropathy associated with bronchial asthma, multisystem organ dysfunction and idiopathic hypereosinophilia may be found in Churg-Strauss syndrome, hypereosinophilic syndrome and polyarteritis nodosa. Some authors have diagnosed their patients according to the presence in tissue biopsies of the three histological criteria of Churg and Strauss (necrotizing vasculitis, tissue eosinophilic infiltration, extravascular granulomas). We have observed three patients with a common history of a prodromal phase of allergic diseases (bronchial asthma and rhinitis) followed by a vasculitic phase with mononeuritis multiplex, purpura and arthritis, associated with hypereosinophilia of more than 1500 cells/mm3. All responded well to steroid treatment. Sural nerve biopsy revealed true vasculitis in two of these cases and a mild perivascular inflammatory infiltration in the other. On the basis of their characteristic clinical pattern, we think that our cases best fit the diagnosis of Churg-Strauss syndrome even though the typical histological features were not found in the sural nerves examined. 相似文献
27.
Negro R Mangieri T Coppola L Presicce G Casavola EC Gismondi R Locorotondo G Caroli P Pezzarossa A Dazzi D Hassan H 《Human reproduction (Oxford, England)》2005,20(6):1529-1533
BACKGROUND: Infertile women positive for thyroid antibodies suffer from a poor pregnancy/delivery outcome, although conflicting data have been published. Our objective was to investigate if levothyroxine (LT4) exerts any effect on pregnancy and/or delivery rates in thyroid peroxidase antibody (TPOAb)-positive (+) women undergoing assisted reproductive technologies. METHODS: Patients undergoing treatment were screened for TPOAb, thyroid-stimulating hormone (TSH) and free thyroxine (FT4). A total of 72 (15%) out of the 484 euthyroid women selected were TPOAb (+). These 72 patients were randomly divided into two groups: group A (n = 36) underwent LT4 treatment, group B (n = 36) placebo. Group C consisted of 412 women (85%) who were TPOAb negative (-). All patients received controlled ovarian stimulation. The endpoints of treatment were pregnancy rate, miscarriage rate and delivery rate. RESULTS: No differences in pregnancy rate were observed between the three groups. Miscarriage rate was higher in TPOAb (+) in comparison to TPOAb (-) [relative risk: 2.01 (95% CI = 1.13-3.56), P = 0.028]. CONCLUSIONS: The pregnancy rate is not affected either by presence of TPOAb or treatment with LT4. However, TPOAb (+) women show a poorer delivery rate compared to TPOAb (-). LT4 treatment in TPOAb (+) does not affect the delivery rate. 相似文献
28.
Genotypes and haplotypes in the IL-1 gene cluster: analysis of two genetically and diagnostically distinct groups of Alzheimer patients 总被引:5,自引:0,他引:5
Seripa D Matera MG Dal Forno G Gravina C Masullo C Daniele A Binetti G Bonvicini C Squitti R Palermo MT Davis DG Antuono P Wekstein DR Dobrina A Gennarelli M Fazio VM 《Neurobiology of aging》2005,26(4):455-464
Increased risk of Alzheimer's disease (AD) has been associated with polymorphisms in the IL-1 gene cluster, and in particular with the IL-1alpha-889 T/T genotype. However, this association is still unclear, and needs further investigation. In order to clarify the role of these polymorphisms in the complex pathogenesis of AD we examined genotype and haplotype frequencies of the two C-to-T SNPs at position -889 and -551 in the IL-1alpha and IL-1beta genes, respectively, and of the 86 bp VNTR intron-2 polymorphisms in the IL-1Ra gene. The analysis was performed in two genetically and diagnostically distinct groups of sporadic AD from Italy and the USA. In the Italian group a significant association between the IL-1alpha-889 T/T genotype and AD (OR=3.022, 95% CI: 1.001-9.119) was found, whereas no difference was found in the group from the USA. Results were also compared with previously published studies that analyzed the same IL-1 polymorphisms in AD. In both groups, the analysis of the estimated haplotypes shows that AD patients and controls who carry the IL-1beta-511 C allele, were also more frequently carriers of the IL-1Ra 1 allele (haplotypes -C-1). The total frequency of the two -C-1 haplotypes (C-C-1 plus T-C-1) was about one half of the total frequency of the eight estimated haplotypes. This was confirmed by significant linkage disequilibrium between these two loci in both the Italian and USA groups. In the Italian group a weak association of the T-C-2 haplotype with the disease (OR=1.648, 95% CI: 1.519-1.788) was also found, whereas in the USA group no difference was found. Although ours and other published data on different samples of Caucasian and non-Caucasian AD show a great heterogeneity in the frequencies of the IL-1alpha-889, the IL-1beta-511 and the IL-1Ra VNTR gene polymorphisms, we confirm the role of the IL-1alpha-889 T/T genotype as a risk factor for sporadic AD, and show the presence of an allelic association between IL-1beta C and IL-1Ra 1 alleles in both the Italian and the USA groups, confirmed by the presence of significant levels of linkage disequilibrium between these two loci. 相似文献
29.
Glycinergic synapses are implicated in the coordination of reflex responses, sensory signal processing and pain sensation. Their activity is pre- and postsynaptically regulated, although mechanisms are poorly understood. Using patch-clamp recording and Ca2 + imaging in hypoglossal motoneurones from rat and mouse brainstem slices, we address here the role of cytoplasmic Ca2 + (Cai ) in glycinergic synapse modulation. Ca2 + influx through voltage-gated or NMDA receptor channels caused powerful transient inhibition of glycinergic IPSCs. This effect was accompanied by an increase in both the failure rate and paired-pulse ratio, as well as a decrease in the frequency of mIPSCs, suggesting a presynaptic mechanism of depression. Inhibition was reduced by the cannabinoid receptor antagonist SR141716A and occluded by the agonist WIN55,212-2, indicating involvement of endocannabinoid retrograde signalling. Conversely, in the presence of SR141716A, glycinergic IPSCs were potentiated postsynaptically by glutamate or NMDA, displaying a Ca2 + -dependent increase in amplitude and decay prolongation. Both presynaptic inhibition and postsynaptic potentiation were completely prevented by strong Cai buffering (20 m m BAPTA). Our findings demonstrate two independent mechanisms by which Ca2 + modulates glycinergic synaptic transmission: (i) presynaptic inhibition of glycine release and (ii) postsynaptic potentiation of GlyR-mediated responses. This dual Ca2 + -induced regulation might be important for feedback control of neurotransmission in a variety of glycinergic networks in mammalian nervous systems. 相似文献
30.
The nonstructural protein 3 (NS3) of Dengue virus (DV) is a multifunctional enzyme carrying activities involved in viral RNA replication and capping: helicase, nucleoside 5'-triphosphatase (NTPase), and RNA 5'-triphosphatase (RTPase). Here, a 54-kDa C-terminal domain of NS3 (DeltaNS3) bearing all three activities was expressed as a recombinant protein. Structure-based sequence analysis in comparison with Hepatitis C virus (HCV) helicase indicates the presence of a HCV-helicase-like catalytic core domain in the N-terminal part of DeltaNS3, whereas the C-terminal part seems to be different. In this report, we show that the RTPase activity of DeltaNS3 is Mg2+-dependent as are both helicase and NTPase activities. Mutational analysis shows that the RTPase activity requires an intact NTPase/helicase Walker B motif in the helicase core, consistent with the fact that such motifs are involved in the coordination of Mg2+. The R513A substitution in the C-terminal domain of DeltaNS3 abrogates helicase activity and strongly diminishes RTPase activity, indicating that both activities are functionally coupled. DV RTPase seems to belong to a new class of Mg2+-dependent RTPases, which use the active center of the helicase/NTPase catalytic core in conjunction with elements in the C-terminal domain. 相似文献