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1.
A case, referred to the Department of Stomatognathic Physiology, G?teborg, with an unstable occlusion is presented. There was a facial asymmetry and the bony morphology differed markedly between the sides. No EMG activity in the masticatory muscles could be detected on the left side. It was diagnosed as a probable sequela to poliomyelitis in the childhood. The impact of altered muscle function on the bony structures and dentition is discussed.  相似文献   
2.
Seventeen consecutive selected patients rehabilitated by means of a full maxillary bridge on osseointegrated implants ad modem Brånemark were evaluated over a 3-yr period. Besides a subjective evaluation by means of a questionnaire an examination of the occlusal relationship, chewing force, chewing efficiency and interocclusal threshold level was performed before, immediately after, 3–6 months after, and finally 3 yr after bridge installation. All subjects were very pleased with the oral rehabilitation. The chewing force and the chewing efficiency development increased over time, while the threshold level for interocclusal detection remained unchanged. The clinical dysfunction index according to Helkimo indicated that there was no marked change in signs of dysfunction of the patients' masticatory systems during the observation period. From the present longitudinal investigation one can conclude that the replacement of a full maxillary denture with a fixed prosthesis on osseointegrated implants, facing a natural dentition or an osseointegrated implant supported bridge in the opposite jaw, leads to a progressive increase of chewing efficiency and chewing force, and a constant subjective improvement of jaw function, while no masticatory dysfunction seems to occur during the observation period.  相似文献   
3.
The Navajo are the largest Indian tribe in the continental U.S. with a population in 1986 estimated at 171,097. The Navajo Nation (Reservation) is located along the borders where Arizona, New Mexico, Colorado and Utah meet. Social and economic changes have accrued among the Navajo at a rapid rate during this century. At present, revenues are derived from oil, coal and uranium and from federal grants and contracts. High unemployment rates have been a major problem among the Navajo.This article reviews health, disease and health care among the present day Navajo. Mortality rates from accidents and suicide are disproportionately high and have as their causes longstanding social and behavioral problems. Although there has been a sharp decline in morbidity and mortality from infectious diseases, there are still major environmental health problems.Sixten S.R. Haraldson, Dr. Med, M.P.H. is Professor of International Development, Clark University and a former Director of the Nordic School of Public Health, Sweden. Address request for reprints to: Dr. Sixten S.R. Haraldson P.O. Box 5, 432 03 Traslovslage, Sweden.The author made study visits to Indian reservations in Arizona in the U.S. in 1974, 1984 and 1985, and had valuable discussions with Catherine Fleshman, M.P.H., B.A. and Kenneth Fleshman, M.D. Both have extensively dealt with health problems among the Navajos and other Native Americans. Dr. Fleshman has practiced clinical medicine and public health with the Indian Health Service for thirty years. Ms. Fleshman is presently conducting health care management implementation studies for a southern Arizona tribe. I am most grateful for their assistance with statistical information and with their unique personal experience.  相似文献   
4.
Clozapine (3.8–60.0 µmol kg?1) did not produce any alterations in DOPA accumulation (following inhibition of cerebral aromaticl-amino acid decarboxylase) in the prefrontal cortex or in three regions of the neostriatum, i.e. the ventral, the dorso-lateral and the posterior regions, in the rat. In contrast, clozapine produced a reduction in the 5-HTP accumulation in all these brain areas, except for the prefrontal cortex. Raclopride (0.08–20.0 µmol kg?1) produced a marked increase in DOPA accumulation in all four brain regions and an increase in 5-HTP accumulation in the dorso-lateral neostriatum (2.5–20.0 µmol kg?1), but not in the other forebrain regions. Treatment with SCH-23390 (0.4–1.6 µmol kg?1) resulted in increased DOPA accumulation in the ventral and posterior parts of the neostriatum. No other changes in the DOPA or 5-HTP accumulation were seen with SCH-23390. Considering the doses of these three compounds needed for suppression of conditioned avoidance behavior and for the induction of cataleptic rigidity, it is concluded that raclopride produces an increased DA synthesis at much lower doses than those needed for behavioral effects. In contrast, the behavioral effects of SCH-23390 or clozapine precedes effects on brain DA synthesis on the dose-effect curve. In fact, the only biochemical effect of clozapine, which was observed in low, yet behaviorally active doses, was a decrease in forebrain 5-HTP accumulation. In conclusion, the present results demonstrate a mismatch, in different directions for raclopride and SCH-23390, as regards the doses needed to produce effects on brain dopamine synthesis and on behavior. Thus, the biochemical effects are seen with lower doses than the behavioral effects for the DA D2 receptor blocking agent, whereas the opposite relationship is the case for the DA D1 receptor antagonist. Taking these two DA receptor subtypes into consideration, the possibility should be considered that clozapine produces its antipsychotic-like behavioral effects on animal behavior primarily by a blockade of brain DA D1, rather than D2, receptors.  相似文献   
5.
The aim of the present study was to investigate whether amperozide, an antipsychotic drug which possesses anti-aggressive and anxiolytic-like properties, stimulates the secretion of oxytocin and if so, by which receptor mechanism. For this purpose, female or male Sprague Dawley rats were given amperozide (0.5, 2.5 and 5.0 mg/kg IP), ritanserin (5.0 mg/kg), raclopride (2.0 mg/kg) and prazosin (1.0 mg/kg) and were subsequently decapitated for collection of blood (30 and 120 min) after injection. Oxytocin levels were measured with radioimmunoassay. Amperozide 2.5 and 5 mg/kg increased plasma levels of oxytocin significantly (P<0.05 and <0.001). The effect appeared maximal about 30 min after injection of the drug and oxytocin levels were almost back to basal within 120 min. Similar effects were obtained in female and male rats as well as in animals that were freely fed or food deprived for 24 h. CSF levels of oxytocin were also increased. Ritanserin, a 5-HT2-receptor antagonist but not the D2 receptor antagonist raclopride or the 1-adrenoceptor antagonist prazosin stimulated oxytocin release. In addition, clozapine, a neuroleptic with potent HT2-antagonistic properties, was a potent releaser of oxytocin, whereas haloperidol was without effect. A possible role for oxytocin in the behavioural effects of amperozide and clozapine remains to be explored.  相似文献   
6.
Rats were treated subchronically (14 days) or acutely (single dose) with the 1-selective adrenoceptor antagonist metoprolol or the 2-selective adrenoceptor antagonist ICI 118,551. Metoprolol (350 mg/kg/day for 14 days, orally) significantly reduced the 5-hydroxytryptophan (5-HTP) accumulation when measured 30 min after inhibition of L-amino acid decarboxylase by NSD 1015 (100 mg/kg IP) in the limbic forebrain, the corpus striatum, the cerebral cortex, the brain stem, and in the cerebellum. ICI 118,551 (0.5 mg/kg, twice daily for 14 days, SC) also significantly reduced the 5-HTP accumulation in the same brain regions except in the corpus striatum and the brain stem. Simultaneously assayed tryptophan levels were largely unaffected. Thus sustained -adrenoceptor blockade causes a decrease in the in vivo rate of tryptophan hydroxylation in various rat brain regions. The subchronic treatments with metoprolol or ICI 118,551 also significantly reduced the endogenous levels of 5-hydroxytryptamine (5-HT) in the various rat brain regions studied. Acute treatment with either metoprolol (2 mg/kg SC) or ICI 118,551 (0.5 mg/kg SC) did not affect the 5-HTP accumulation or the endogenous 5-HT levels in the brain regions studied. This inhibitory effect on brain 5-HT systems produced by sustained -adrenoceptor blockade may be of significance both for the long-term cardiovascular action and for occasional neuropsychiatric side effects during -blocking therapy.  相似文献   
7.
PURPOSE: Renal cell carcinoma (RCC) is the most common malignancy of the kidney composed of specific tumor types. The sporadic conventional RCCs are, in contrast to the other RCC types, characterized by a high rate of von Hippel-Lindau (VHL) mutations and hypermethylation. The majority of these tumors lack functional VHL protein (pVHL) that leads to increased hypoxia-inducible factor 1alpha (HIF-1alpha) expression. The pVHL is the physiologic regulator of the activity of HIF-1alpha by targeting it to the proteasome for degradation under normoxia. Both pVHL and HIF-1alpha target other genes that are important for cancer survival and proliferation. Expression of HIF-1alpha has been linked to poor prognosis in different malignancies, although few studies have been done on the relation between HIF-1alpha and clinical variables in RCC. EXPERIMENTAL DESIGN: HIF-1alpha protein expression was analyzed in tumor tissue from 92 patients with RCC. HIF-1alpha was quantified by Western blot relative to a positive control. RESULTS: The HIF-1alpha protein was expressed as two bands which strongly correlated (r = 0.906, P < 0.001); therefore, they were added and the sum evaluated against clinicopathologic variables. There was no association between HIF-1alpha and gender, stage, grade, tumor size, or vein invasion. Conventional RCCs had significantly higher HIF-1alpha expression compared with papillary and chromophobe RCCs and kidney cortex. In conventional RCC, HIF-1alpha was an independent prognostic factor. CONCLUSION: HIF-1alpha levels varied significantly between the different RCC types. In conventional RCC, HIF-1alpha was an independent prognostic factor. These data indicate that HIF-1alpha is involved in tumorogenesis and progression of RCC. Evaluation of other HIF target gene products and correlation to angiogenesis seems warranted.  相似文献   
8.
OBJECTIVE: To evaluate serum parathyroid hormone-related protein (PTHrP) in relation to serum calcium and clinical outcome of patients with renal cell carcinoma. METHODS: Sera from 243 patients with renal cell carcinoma were collected prior to therapy. Serum PTHrP was analyzed using an immunoradiometric assay. Tumour stage, nuclear grade, corrected serum calcium, and survival were assessed. RESULTS: Serum PTHrP was detectable in 37/243 sera (15%) and hypercalcaemia (> or =2.60 mmol/l) in 32/220 (15%). A positive correlation between serum PTHrP and serum calcium was found (r = 0.326; p < 0.01). Following subdivision of the material, based on storage time, the frequency of detectable serum PTHrP seemed to decrease with time. Serum calcium, but not serum PTHrP, was correlated to tumour stage (p < 0.001). Survival was similar for patients with detectable and undetectable PTHrP, but those with hypercalcaemia had a significantly shorter survival time compared to those with normal serum calcium (p < 0.001). A multivariate analysis showed that tumour stage and serum calcium were independent prognostic factors, but not grade or PTHrP. CONCLUSIONS: A positive relation of serum PTHrP to serum calcium was demonstrated in patients with renal cell carcinoma. Hypercalcaemia but not serum PTHrP predicted a worse prognosis.  相似文献   
9.
Objective. To investigate the associations between oral sugar clearance and the prevalence of dental decay. Material and Methods. A total of 92 (44 F, 48 M) 71-year-old subjects in Göteborg, Sweden were consecutively chosen from a representative cohort study. The subjects were examined for: 1) caries-related status, 2) oral function, 3) salivary conditions, 4) cariogenic micro-organisms, and 5) oral sugar clearance. A factor analysis was used to investigate the possible existence of latent variables within these five areas. The latent variables from the factor analyses were used to study the associations between clearance and caries in multivariate regression models. Results. Only one latent variable relating to oral sugar clearance was found. In the regression model with the latent variable related to oral sugar clearance as a dependent variable and gender plus the latent variables related to oral function and salivary conditions as an independent variable, there were associations with gender and some latent variables reflecting oral function and one reflecting glucose in saliva (R2=0.20/0.17). Three latent variables relating to caries-related status were found and these were associated with the number of teeth, the percentage of filled tooth surfaces, and the percentage of decayed tooth surfaces (DS%). In the regression analysis using the latent variable associated with DS% as a dependent variable, this variable was related to the latent variables of oral sugar clearance and to some reflecting oral function, as well as glucose in saliva (R2=0.28). Conclusions: Oral sugar clearance appears to be independently associated with the prevalence of dental caries in the elderly.  相似文献   
10.
The findings that dopamine D3 and D4 receptors are highly expressed in limbic and cortical areas (D4 more than D3), and the fact that the atypical drug clozapine has preferential affinity for the D4 receptors have suggested an involvement of these receptors in schizophrenia. Subsequently, many pharmaceutical companies have pursued the approach of developing selective dopamine D3 or D4 antagonists as potential antipsychotics. This review will discuss the current status of selective dopamine D3 and D4 receptor antagonists for the treatment of schizophrenia.  相似文献   
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