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1.
The last generation of mammographic equipment allows mammography to be performed with direct magnification techniques, thanks to such technical features as microfocus, high focus-film distance, high-power generators. The authors compared the diagnostic yield of two different equipment sets, with 1.4x and 2x magnification respectively, and verified the utility of magnification radiography. A significant reduction was obtained in questionable diagnoses (42 to 18) in a group of 63 patients, with no evidence of substantial differences in the diagnostic yield of the images obtained with different magnification ratios. An objective analysis of the system resolution power privileges 2x magnification ratio, which however implies an increase in the average dose to the breast. The use of faster recording systems reduces the dose by 50%, though maintaining good image quality.  相似文献   
2.
Sixty-six students were randomly assigned to a vigilance task during which observing responses produced targets according to either a fixed-interval or random-interval 90-sec schedule. During the task, interbeat interval, masseter (EMG) activity, blood pressure and digital blood volume pulse were monitored. Vasoconstriction was initiated within a 4 to 6-sec period following target detection for the majority of subjects assigned to each schedule. Vasomotor tone returned to prechange levels approximately 16 sec after target detection. Transient heart rate increases also occurred during the post-event period, but were more prevalent with subjects in the fixed than in the random-interval group. Post-event masseter activity was exhibited infrequently and only by subjects assigned to the fixed-interval group. The involvement of cardiovascular responsiveness with human schedule-induced behavior and the implications of this involvement for arousal theories of schedule-induced behavior are discussed.  相似文献   
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A 1H and 13C NMR study on the inclusion complex of paroxetine with β-cyclodextrin was carried out in order to define the stoichiometry of the association and its strength. Proton and carbon chemical shift measurements of paroxetine and β-cyclodextrin were performed at several molar ratios and temperatures, allowing the determination of a 1:1 stoichiometry and an association constant value of the order of 2 × 103 for the paroxetine–β-cyclodextrin complex. Overhauser effects in the rotating frame were also measured, and the experimental interproton distance constraints have been used for molecular model building of the complex. The obtained model indicates that the benzodioxolyl moiety of paroxetine is deeply inserted in the cavity of the cylindrical structure of β-cyclodextrin, while the fluoro-phenyl ring lays above the wider rim.  相似文献   
5.
Aims: Nestin (a neuronal stem cell/progenitor cell marker of central nervous system development), vimentin (which is ubiquitously expressed in mesenchymal cells), and the glucocorticoid receptor (GR, which is involved in the immune response, cell proliferation, and apoptosis) have been shown to interact in embryonic and undifferentiated tissues in modulating cell proliferation. The aim of this study was to analyse nestin, vimentin and GR expression in tumour tissue (melanoma), and their association with clinicopathological variables, to evaluate any effect on tumour progression. Methods and results: Immunohistochemistry, double‐label immunofluorescence and confocal laser scanning microscopy were performed on biopsy specimens of cutaneous melanoma from 81 patients. Fisher’s and Pearson’s tests showed a correlation between nestin, vimentin and subcellular GR location (P = 0.008). Their concomitant expression also correlated with Clark level and thickness (P = 0.02 and P = 0.029, respectively). Kaplan–Meier analysis revealed a poorer outcome for stage III and IV patients with associated expression of nestin, vimentin and cytoplasmic GR in tumour tissue (P = 0.02). Conclusions: These results suggest the presence in melanoma of growth mechanisms involving nestin, vimentin, and GR, similarly to that occurring in embryonic and undifferentiated cells, and may help in understanding tumour biology to provide a molecular basis for clinical therapies.  相似文献   
6.
Background:  Addictive drugs activate extracellular signal regulated kinase (ERK) in brain regions critically involved in their affective and motivational properties. The aim of this study was to demonstrate the ethanol-induced activation of ERK in the nucleus accumbens (Acb) and in the extended amygdala [bed nucleus of the stria terminalis lateralis (BSTL) and central nucleus of the amygdala (CeA)] and to highlight the role of dopamine (DA) D1 receptors in these effects.
Methods:  Ethanol (0.5, 1, and 2 g/kg) was administered by gavage and ERK phosphorylation was determined in the nucleus Acb (shell and core), BSTL, and CeA by immunohistochemistry. The DA D1 receptor antagonist, SCH 39166 (SCH) (50 μg/kg), was administered 10 minutes before ethanol (1 g/kg).
Results:  Quantitative microscopic examination showed that ethanol, dose-dependently increased phospho-ERK immunoreactivity (optical and neuronal densities) in the shell and core of nucleus Acb, BSTL, and CeA. Pretreatment with SCH fully prevented the increases elicited by ethanol (1 g/kg) in all brain regions studied.
Conclusions:  The results of this study indicate that ethanol, similar to other addictive drugs, activates ERK in nucleus Acb and extended amygdala via a DA D1 receptor-mediated mechanism. Overall, these results suggest that the D1 receptors/ERK pathway may play a critical role in the motivational properties of ethanol.  相似文献   
7.
Despite high rates of osseointegration in healthy patients, complex cases present an increased risk of osseointegration failure when treated with dental implants. Furthermore, if immediate loading of the implants is used, maximizing the response of the host organism would be desirable. Anabolic steroids, such as Nandrolone Decanoate (ND), are reported to have beneficial clinical effects on various bone issues such as osteoporosis and bone fractures. However, their beneficial effects in promoting osseointegration in dental implant placement have not been documented. The study aimed to examine histological changes induced by ND in experimental dental implants in rabbit models. Two dental implants were placed in the tibias of 24 adult rabbits. Rabbits were allocated to one of two groups: control group or test group. Rabbits in the latter group were given nandrolone decanoate (15 mg/kg, immediately after implant placement and after 1 week). Micro-radiographic and histological analyses were assessed to characterize the morphological changes promoted by the nandrolone decanoate use. Total bone volume and fluorescence were significantly higher in the control group after 2 weeks. Such a difference between the two groups might indicate that, initially, nandrolone lengthens the non-specific healing period characteristic of all bone surgeries. However, after the beginning of the reparative processes, the quantity of newly formed bone appears to be significantly higher, indicating a positive stimulation of the androgen molecule on bone metabolism. Based on micro-radiology and fluorescence microscopy, nandrolone decanoate influenced bone regeneration in the implant site. The anabolic steroid nandrolone decanoate affects the healing processes of the peri-implant bone and therefore has the potential to improve the outcomes of implant treatment in medically complex patients.  相似文献   
8.
The normal and abnormal aspects of the epitrochlear lymphatic station are not well known, mainly because the axillary basin is commonly regarded as the primary lymphatic target of all upper limb disorders. The purpose of this paper is to illustrate, through a review of specific cases, the normal and abnormal findings that can emerge during ultrasonographic (US) and color-Doppler US exploration of the epitrochlear region. We illustrate the normal anatomy and variations of the epitrochlear lymph nodes and highlight the functional role of this lymphatic station. Subsequently we describe the US and color-Doppler US findings. A number of different abnormalities are reviewed, including metastases (mainly from upper limb cutaneous melanomas), Hodgkin disease, and non-Hodgkin lymphoma, lymphadenitis (cat-scratch disease, foreign bodies, and IV drug abuse). Measures are suggested to avoid interpretative pitfalls and to carry out an effective differential diagnosis of elbow masses. This article represents a pictorial essay of the US and color-Doppler US features of various epitrochlear lymph node abnormalities that clinicians may not be familiar with.  相似文献   
9.
Since the immune response in older recipientsis weaker they should be less likely to rejecta transplanted organ and should need lessaggressive immunosuppressive treatment. Our aimwas to record the incidence and severity ofepisodes of acute rejection (AR), estimate theinfluence of these events on graft survival ofelderly recipients (60) and to comparethese with that in younger ones.We performed 363 kidney transplants between1/94 and 12/98, and recorded clinical andimmunological data, incidence-severity of ARand cause of graft loss. Patients were dividedinto two groups, according to the age attransplantation: A (<60, n = 281/77.4%) and B( 60, n = 82/22.6%). The percentage ofaging recipients and mean age of donors andrecipients increased throughout the period.Although the incidence of ATN was higher in theolder group (29% vs.19%, p < 0.0001) thenumber of graft biopsies was equal in bothgroups. The incidence of AR was similar, 33.4%vs. 26.8%, pNS. The number of AR episodes perpatient was 0.44 and 0.41 respectively. Theseverity of AR was: Banff grade I: A (40.3%)/B (45.7%) pNS; grade II: A (44.1%)/B(48.57) pNS; grade III: A (15.5%)/B (5.7%)pNS. Younger recipients presented a higherlevel of panel-reactive antibodies (PRA) (4.3%vs. 2.07%, p = 0.01). One-year patient survivalwas 96%/91% (p<0.05) and graft survivalwas 81%/78% (pNS) respectively.The age of recipient does not seem to haveinfluenced the incidence-severity of AR or thegraft survival. Thus immunosuppression shouldbe individualised for each patient and shouldnot depend on the age at transplantation.  相似文献   
10.
Proteinuria in the general population has been shown to be associated with cardiovascular disease, which is the main cause of death in renal transplantation. We investigated the effect of proteinuria on cardiovascular disease after renal transplantation in 532 renal transplant patients with functioning grafts for more than 1 year. Patients were classified into two groups depending on the presence of persistent proteinuria. We analyzed graft and patient survival, posttransplantation cardiovascular disease, and main causes of graft loss and death. Five- and 10-year graft and patient survival rates were lower in the group with proteinuria. The main cause of death was vascular disease in both groups. The presence of posttransplantation cardiovascular disease was higher in the group with proteinuria. Persistent proteinuria was associated with graft loss (RR=4.18), patient death (RR=1.92), and cardiovascular disease (RR=2.45). In conclusion, persistent proteinuria was an independent risk factor for increased cardiovascular morbidity and mortality in renal transplant patients.  相似文献   
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