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排序方式: 共有6878条查询结果,搜索用时 15 毫秒
31.
Roberta Giordano Rita Berardelli Ioannis Karamouzis Valentina D’Angelo Andreea Picu Clizia Zichi Beatrice Fussotto Maria Manzo Giulio Mengozzi Ezio Ghigo Emanuela Arvat 《Pituitary》2013,16(3):363-369
The purpose of this study is to verify whether acute pre-treatment with alprazolam (ALP), a benzodiazepine that inhibits HPA secretion in normal subjects, could better characterize patients with subclinical Cushing’s syndrome (SCS) than the 1-mg dexamethasone test (DST). In 22 patients with SCS, 10 with overt Cushing’s syndrome (CS), 11 with non-functioning adrenal incidentalomas (NF) and 14 normal subjects (NS) we studied the effect of ALP (1 mg, p.o. at 2300 hours) on cortisol levels after 1-mg DST. Cortisol levels (mean ± SEM) after DST were lower (P = 0.012) in SCS (3.9 ± 0.3 μg/dl) than in overt CS (10.4 ± 1.9 μg/dl), while they were higher (P = 0.0005) than in NF (1.1 ± 0.1 μg/dl) and NS (1.5 ± 0.1 μg/dl). After ALP pre-treatment, cortisol levels further decreased (P = 0.004) in SCS (3.0 ± 0.3 μg/dl), but neither in CS (9.3 ± 1.3 μg/dl) nor in NF (1.3 ± 0.1 μg/dl) and in NS (1.3 ± 0.1 μg/dl). In SCS, cortisol levels after ALP + 1-mg DST persisted lower (P = 0.0005) than those in CS, but higher (P = 0.0005) than those in NF and NS. Considering individual cases, ALP pre-treatment reduced cortisol levels <3 and <1.8 μg/dl in 50 and 23 % of SCS patients, respectively. ALP amplifies the cortisol inhibition exerted by 1-mg DST in patients with SCS but not in those with CS. The clinical usefulness of ALP to increase the sensitivity of 1-mg DST to identify true autonomous cortisol release in patients with adrenal incidentalomas as well as to predict different clinical outcomes remains to be clarified. 相似文献
32.
Dedepsidis E Karakasiliotis I Paximadi E Kyriakopoulou Z Komiotis D Markoulatos P 《Virus genes》2006,33(2):183-191
In the present study, a genomic analysis of full VP1 sequence region of 15 clinical re-isolates (14 healthy vaccinees and
one bone marrow tumor patient) was conducted, aiming to the identification of mutations and to the assessment of their impact
on virus fitness, providing also insights relevant with the natural evolution of Sabin strains. Clinical re-isolates were
analyzed by RT-PCR, sequencing and computational analysis. Some re-isolates were characterized by an unusual mutational pattern
in which non-synonymous mutations outnumbered the synonymous ones. Furthermore, the majority of amino-acid substitutions were
located in the capsid exterior, specifically in N-Ags, near N-Ags and in the north rim of the canyon. Also mutations, which
are well-known determinants of attenuation, were identified. The results of this study propose that some re-isolates are characterized
by an evolutionary pattern in which non-synonymous mutations with a direct phenotypic impact on viral fitness are fixed in
viral genomes, in spite of synonymous ones with no phenotypic impact on viral fitness. Results of the present retrospective
characterization of Sabin clinical re-isolates, based on the full VP1 sequence, suggest that vaccine-derived viruses may make
their way through narrow breaches and may evolve into transmissible pathogens even in adequately immunized populations. For
this reason increased poliovirus laboratory surveillance should be permanent and full VP1 sequence analysis should be conducted
even in isolates originating from healthy vaccinees. 相似文献
33.
Papathomas TG Venizelos I Dunphy CH Said JW Wang ML Campo E Swerdlow SH Chan JC Bueso-Ramos CE Weisenburger DD Medeiros LJ Young KH 《Human pathology》2012,43(4):467-480
Composite lymphoma is a rare circumstance in which 2 or more distinct types of lymphoma occur in a single anatomical location. Although composite lymphoma has been increasingly identified with the advent of molecular genetic techniques, this topic has only rarely been a specific focus of the medical scientific literature. In this review, we focus on mantle cell lymphoma occurring as a major pathologic component of composite lymphoma and emphasize the clinicopathologic features of these tumors and associated biologic implications. To date, 26 cases of composite lymphoma including a component of mantle cell lymphoma have been previously published. Issues of clonal relatedness between the individual lymphoma components and emerging biologic implications as well as potential diagnostic pitfalls are evaluated. 相似文献
34.
Vasileios Boulougouris Ioannis Malogiannis George Lockwood Iannis Zervas Giuseppe Di Giovanni 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》2013,230(4):605-624
Many studies have provided important information regarding the anatomy, development and functional organization of the 5-HT system and the alterations in this system that are present within the brain of the suicidal patient. There is also a growing interest in genetic factors associated with suicide, since these may lead to the emergence of personality traits that prove to be long-term predictors of suicidal behaviour. This review will focus on presenting the scientific literature on the role of the serotonergic system in suicidal behaviour as well as dysfunctional attitudes and personality traits associated with the suicidal patient. The association of the serotonin transporter gene, the 5-HT2 receptors and its metabolite 5-hydroxyindoleacetic acid with suicidal behaviour and animal models that may capture the complexity of suicidal behaviour will be discussed. Finally, the relationship between neurobiological models and psychotherapeutic interventions for suicide prevention will be considered with a focus on Schema Therapy (an approach that has shown particular promise in the treatment of suicidal individuals with personality disorders), aiming to invite the reader to integrate some aspects of the neurobiology of human suicidal behaviour into a model of suicide that can be used in a clinical encounter. 相似文献
35.
Emmanouil V. Dermitzakis Georgios Georgiadis Jobst Rudolf Dimitra Nikiforidou Panagiotis Kyriakidis Ioannis Gravas Chrysanthi Bouziani Iakovos Tsiptsios 《The journal of headache and pain》2010,11(2):123-128
The aim of this study was to record the demographic and epidemiological data on adult patients with headache who attend the emergency department (ED) and the diagnoses that made by the neurologists in the ED of a tertiary care hospital in metropolitan Thessaloniki (Greece). In an open prospective study, demographic and epidemiological data were collected on all patients who reported headache (as chief complaint or not) and presented to the ED of Papageorgiou Hospital between August 2007 and July 2008. Headache patients accounted for 1.3% of all ED patients and for 15.5% of patients primarily referred to the ED neurologist. Tension type headache was the most frequent diagnosis, followed by secondary headaches and migraine. The large number of patients without final ED diagnosis and ward admission for further evaluation sheds a light on the immense workload of Greek ED physicians. Furthermore, we found evidence for the misuse of Emergency Medical Services by chronic headache patients. These findings indicate shortcomings in the pre-hospital (primary care) management of headache patients in the Greek National Health System to an extent unreported so far. 相似文献
36.
Ioannis S Elefsiniotis Aikaterini Petrocheilou Nikolaos Scarmeas Ioannis Ketikoglou Konstantinos D Pantazis Marina Toutouza Epameinondas V Tsianos 《Journal of clinical virology》2006,37(4):329-331
OBJECTIVES: To evaluate the alterations of serum procalcitonin (PCT) levels in patients with chronic hepatitis C during pegylated interferon-alpha (PEG-IFNa) plus ribavirin (RIB) treatment and to correlate them with clinical and virological outcomes. STUDY DESIGN: Fifty-two consecutive patients (29 males, age=41.2+/-14.7 years) with chronic HCV-related liver disease (six cirrhotics) were evaluated for PCT levels at baseline and during the treatment course (at week 12, 24, 48 and 72) with PEG-IFNa plus RIB. Sustained virological response (SVR) was confirmed by undetectable serum HCV-RNA at the end of treatment and again 6 months after completion of treatment. RESULTS: Two patients exhibited culture-proved bacterial infections during the treatment course. Thirty-six patients (69.2%) exhibit SVR and 16 (30.8%) were non-responders. Serum PCT levels remained within normal limits (0.1-0.5 ng/mL) in all treated patients throughout the follow-up period except those two who exhibited bacterial infections during the treatment course. Virological responders exhibited significant decline of serum PCT levels over time compared to non-responders (p<0.001), even when adjusted for multiple baseline parameters (p=0.037). CONCLUSION: Serum PCT levels decline in chronic hepatitis C patients during PEG-IFNa plus RIB treatment, especially in the sustained virological responder group, while they elevate only when bacterial infections complicate the treatment course. 相似文献
37.
It is well known that magnetic susceptibility variations lead to signal voids in MRI. However, recent work has shown that positive-contrast imaging of susceptibility-induced field variations can provide signal enhancements rather than signal losses. In this paper, we propose a new method for generating positive contrast from off-resonant spins with steady-state free precession (SSFP) magnetic resonance imaging. Based on theory and experiments, we demonstrate that positive-contrast images can be acquired in the presence of susceptibility-shift media with low flip angle excitations that are determined by the spin relaxation time constants of the imaging medium. Compared to other techniques, this technique is substantially faster and has low specific absorption rates, permitting high-field imaging. In addition to acquiring positive-contrast images, we also show that it is possible to suppress the imaging medium to desired levels; thereby allowing for simultaneous registration of the background details surrounding the susceptibility-shift media. Among practical applications, we anticipate that the proposed technique can potentially facilitate high field magnetic-resonance-based molecular imaging. 相似文献
38.
Dimopoulou I Tsagarakis S Anthi A Milou E Ilias I Stavrakaki K Charalambidis C Tzanela M Orfanos S Mandragos K Thalassinos N Roussos C 《Critical care medicine》2003,31(4):1113-1117
OBJECTIVE: To investigate the adrenocortical function in brain-dead patients, potential organ donors. DESIGN: Prospective study. SETTING: Intensive care units in two teaching hospitals. PATIENTS: A total of 37 patients (28 men, nine women) with severe brain injury, having a mean age of 42 +/- 18 yrs, were included in the study. Group A consisted of 20 brain-injured patients who did not deteriorate to brain death. Group B included 17 brain-injured patients who were brain dead; of these, ten patients developed brain death during ICU stay and seven patients were admitted to the ICU after clinical brain death. INTERVENTIONS: In all patients (group A and group B), a morning blood sample was obtained at admission to the ICU to determine baseline plasma cortisol. Subsequently, 1 microg of corticotropin (adrenocorticotropic hormone, Synacthen) was administered intravenously, and a blood sample was taken 30 mins after the injection. In group B patients who became brain dead while being treated in the ICU (n = 10), the same procedure was repeated the morning after the confirmation of brain death. Patients having a cortisol level of at least 18 microg/dL after the administration of adrenocorticotropic hormone were defined as responders. MEASUREMENTS AND MAIN RESULTS: After the occurrence of brain death, group B patients had significantly lower values for baseline (8.5 +/- 6.2 vs. 17.0 +/- 6.6 microg/dL, p <.001) and stimulated (16.9 +/- 6.3 vs. 23.9 +/- 5.7 microg/dL, p =.001) plasma cortisol compared with group A patients. Thirteen group B patients (76%) and two group A patients (10%) were nonresponders to adrenocorticotropic hormone (p <.001). In group B patients, baseline and stimulated cortisol concentrations were significantly related (r =.71, p =.001), whereas there was no correlation between baseline cortisol and the increment in cortisol (r = -.37, p =.15). Mean hormonal data of the ten brain-dead patients studied at admission in the ICU and after the occurrence of brain death were the following: baseline plasma cortisol (23.5 +/- 11.4 vs. 6.8 +/- 4.2 microg/dL, p =.003) and stimulated serum cortisol (28.8 +/- 9.9 vs. 16.3 +/- 4.3 microg/dL, p =.008). CONCLUSIONS: Adrenal cortisol secretion after dynamic stimulation is deficient in a substantial proportion of brain-dead potential organ donors. 相似文献
39.
Characterization and clinical application of human CD34+ stem/progenitor cell populations mobilized into the blood by granulocyte colony-stimulating factor 总被引:13,自引:0,他引:13
Gordon MY Levicar N Pai M Bachellier P Dimarakis I Al-Allaf F M'Hamdi H Thalji T Welsh JP Marley SB Davies J Dazzi F Marelli-Berg F Tait P Playford R Jiao L Jensen S Nicholls JP Ayav A Nohandani M Farzaneh F Gaken J Dodge R Alison M Apperley JF Lechler R Habib NA 《Stem cells (Dayton, Ohio)》2006,24(7):1822-1830
40.
Nikolaos Koufos Despina Michailidou Ioannis D. Xynos Periclis Tomos Kalliopi Athanasiadou Christos Kosmas Nikolaos Tsavaris 《Journal of cancer research and clinical oncology》2013,139(12):1995-2003