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51.
Human intercommunication means transfer of information through many channels, with codes that have biological and socio-cultural determinism. The biological determinism is identifiable through the development of the phonetics and ergomotricity functions, through the possibility of perception of the sensorial organs. The channels of human intercommunication can be verbal, linguistic (the most specialised channel), and nonverbal, extralinguistic channels (mimics, written model, drawing, walking), that are effectively implicated in defining a direct dialogue between the dentist and the patient, completing and emphasising the communication. When the communication through the standard channels is disturbed, the dentist can't understand the patient's expectations, so the patient will not perceive the opportunity, the necessity and the efficiency of the complex oral rehabilitation. All these factors are contributing to the initiation of the iatrogeny through communication.  相似文献   
52.
BACKGROUND AND PURPOSE: The time courses of total creatine (Cr), N-acetylaspartate (NAA), choline (Cho), and myo-inositol have not previously been investigated in the follow-up of contrast-enhancing multiple sclerosis (MS) plaques. Therefore, over a period of 2 years, we compared the absolute concentrations of these metabolites between patients treated with a placebo or 15 +/- deoxyspergualin (DSG) and between clinical groups with relapsing-remitting or secondary-progressive MS. METHODS: Sixteen patients, recruited from a pharmacological study of DSG, and 11 healthy control subjects were investigated by a stimulated-echo acquisition mode sequence (TR/TE = 3000/20). The selected volume initially contained a contrast-enhancing plaque, which was followed up for a period of 2 years. RESULTS: In contrast-enhancing plaques, Cho was significantly elevated and showed a significant reduction after both 3 and 12 months. The initially normal Cr significantly increased between 3 and 12 months, and was negatively correlated with plaque volume on T1-weighted MR images. NAA initially showed normal values, a significant decrease at 1 month, and a slow recovery over 2 years. Myo-inositol did not show a clear tendency. The placebo group did not differ from the treated group, nor did the relapsing-remitting group differ from the secondary-progressive group. CONCLUSION: The contradictory time courses of Cr and NAA show that an absolute quantification in proton MR spectroscopy in MS is necessary to avoid a false interpretation of reduced NAA/Cr ratios. The increase in Cr is probably due to remyelination. The initial dip and later recovery of NAA seem to be related to diminishing edema and remyelination.  相似文献   
53.
Summary Background. The aim of this study is to assess the morbidity and mortality of meningioma surgery in patients over 70 years of age harbouring a tumour at the cerebellopontine angle as one representative location of the posterior fossa in comparison with a matched group of young patients.Method. A retrospective analysis based on clinical charts, surgical records, histological records, imaging studies and follow up records was conducted to select patients over 70 years who underwent surgery for cerebellopontine angle meningiomas. Tumours with comparable size and location were matched with the younger group.Findings. There were 421 meningiomas located in the cerebellopontine angle, 21 patients were older than 70 years (range 70–84). Median Karnofsky-Index at presentation was 80 (50–90), 16 patients had a physical status grading ASA 2 and 5 patients ASA 3. The average length of hospital stay was 22 days (7–99 days). The postoperative median Karnofsky score at time of discharge was 80 (50–90). The most common medical complication was postoperative pneumonia in 4 patients, among them 3 patients had lower cranial nerve disturbances postoperatively. There were 56 younger patients (mean age 52.4 years; range 24.5–69.75 years) with corresponding tumour size and location. Pre-op Karnofsky score was 80 (70–90), 53 patients were graded as ASA 2 and 3 patients as ASA 3. Length of hospital stay was 13.6 days (8–32 days). Post-op Karnofsky score was 80 (50–90). Among 5 patients with postoperative lower cranial nerve disturbances no patient had pneumonia postoperatively. There was no peri-operative mortality in either group.Conclusions. With modern neurosurgical techniques and neuro-anesthesia elderly patients with CPA meningiomas can be operated on with acceptable low morbidity and good neurological outcome but recovery from surgery lasts longer compared to younger patients. However, postoperative lower cranial nerve deficits in elderly patients may not be well tolerated compared with younger patients.  相似文献   
54.
55.
Background: Nonalcoholic fatty liver disease (NAFLD) and nonalcoholic steatohepatitis (NASH) are conditions gaining increasing recognition in hepatology as a potential cause of cirrhosis and end-stage liver disease. Obesity is one of the main risk factors. The aims of this study were to determine the frequency of NAFLD in obese patients and to identify variables that predict NASH. Methods: A prospective study was conducted of obese patients undergoing gastric bypass over a 20-month period. Assessment included liver function tests and evaluation of insulin resistance with the homeostatic model assessment (HOMA-IR). Liver biopsy was performed in all patients at the time of surgery. Clinical and biochemical variables were analyzed using a multivariate analysis to identify independent predictors of NASH. Results: 127 consecutive patients were included (62% female, 38% male, mean age 40±11 years, mean body mass index 42±6 kg/m2). Arterial hypertension was present in 52 patients (41%) and type 2 diabetes in 18 (14%). NAFLD was confirmed in 80 patients (63%), 47 (37%) had simple steatosis, and 33 (26%) had NASH. Cirrhosis was found in 2 patients corresponding to 1.6% of the total population. On multivariate analysis, AST >31 (IU/L) (OR 3.38, CI 1.17-9.8) and HOMA-IR >5.8 (OR 4.18, CI 1.39-12.49) independently predicted NASH. Conclusions: NAFLD is highly prevalent in morbidly obese patients. A high proportion of these patients exhibit NASH on histological examination. Insulin resistance represents the main predictor of NASH.  相似文献   
56.
Our experiments have provided additional data in support of the concept that different mast cell activators follow distinct biochemical pathways in the initiation of secretion and degranulation. To do this we have taken advantage of the observation that some serum proteins, and albumins in particular, have the capacity to inhibit selectively the release of amines from rat peritoneal mast cells initiated by some, but not all, stimuli. We show that the relative inhibition of release obtained is independent of the concentration of activator but dependent upon the concentration of albumin, indicating that the inhibitory process does not involve a direct activator-inhibitor interaction. Finally, our data demonstrate that the inhibition does not interfere with the ability of the activator to interact with the mast cell. Thus, cells incubated with activator in the presence of inhibitor become increasingly unresponsive, or desensitized, to subsequent challenge with activator in the absence of inhibitor. These combined data therefore provide evidence, that, in addition to a selectivity in the activation/desensitization process initiated by different mast cell stimuli, at least one of the biochemical steps subsequent to the activation step is also not shared by all mast cell stimuli.This is publication Number 1004 from the Department of Immunopathology, Scripps Clinic and Research Foundation, La Jolla, California. This research was supported by AI 07007 and HL 16411.Recipient of USPHS Research Career Development Award K-04 AI 00081.  相似文献   
57.
Susceptibility to some stress-induced pathologies may be strongly related to individual differences in the responsiveness of the hypothalamic-pituitary-adrenal (HPA) axis to stressors. However, there have been few attempts in rodents to study the reliability of the individual differences in the responsiveness of the HPA to stressors and the relationship to resting corticosterone levels. In the present work, we used a normal population of Sprague-Dawley rats, with a within-subject design. Our objectives were to study: (a) the reliability of the ACTH and corticosterone response to three different novel environments widely used in psychopharmacology and (b) the relationship between stress levels of HPA hormones and the daily pattern of corticosterone secretion (six samples over a 24-h-period). Animals were repeatedly sampled using tail-nick procedure. The novel environments were the elevated plus-maze, the hole-board and the circular corridor. Animals were sampled just after 15 min exposure to the tests and again at 15 and 30 min after the termination of exposure to them (post-tests). The hormonal levels just after the tests indicate that the hole-board seems to be more stressful than the circular corridor and the elevated plus-maze, the latter being characterized by the lowest defecation rate. Correlational analysis revealed that daily pattern of resting plasma corticosterone levels did not correlate to HPA responsiveness to the tests, suggesting no relationship between resting and stress levels of HPA hormones. In contrast, the present study demonstrates, for the first time, a good within-subject reliability of the ACTH and corticosterone responses to the three environments, suggesting that HPA responsiveness to these kind of stressors is a consistent individual trait in adult rats, despite differences in the physical characteristics of the novel environments.  相似文献   
58.
59.
Dumbbell shaped epidural cavernomas are uncommon lesions. Of these, the extraforaminal extension is usually limited, and the lesions are removed surgically by an extended laminectomy. We present two cases of dumbbell shaped epidural cavernomas with a considerable intrathoracic growth. They were resected through a combined thoracotomy and laminectomy. Only in the case in which a wide approach to the posterior mediastinum was performed it was possible to completely remove the lesion. Since it is possible to anticipate this histological diagnosis by the magnetic resonance imaging characteristics, we propose that a wide transthoracic approach should be performed associated to a laminectomy if a complete resection of the lesion is the goal.  相似文献   
60.
We used double-label in situ hybridization to examine the cellular localization of 5-ht(5B) receptor mRNA in relation to serotonin transporter mRNA in the rat dorsal raphe (DR) and central superior nucleus (CS, median raphe nucleus). 5-ht(5B) receptor mRNA hybridization signal was often found on serotonin transporter mRNA-positive neuron profiles. The degree of cellular colocalization of these mRNAs notably varied among the different regions of the raphe nuclei. In the DR, cell bodies showing 5-ht(5B) receptor mRNA expression were abundant in the medial portions of the nucleus, all of them being also labeled for serotonin transporter mRNA. In contrast, in the ventrolateral regions (lateral wings) of the DR, we observed serotonin transporter mRNA-positive cells, but they were devoid of 5-ht(5B) receptor mRNA signal. In the CS, the level of coexpression of 5-ht(5B) receptor mRNA with serotonin transporter mRNA was high in the intermediate portions of the nucleus; however, we were unable to detect specific 5-ht(5B) receptor mRNA hybridization signal in its caudal extent. Our results support the presence of 5-ht(5B) receptor in serotonergic neurons in the DR and CS, suggesting an autoreceptor role for this receptor subtype.  相似文献   
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