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81.
Riassunto Nell'ambito del progetto «Flora Palinologica Italiana» e proseguendo lo studio delle Corylaceae, è qui presentata la scheda diCarpinus betulus L., con alcune osservazioni sul numero/posizione delle aperture e sulle principali differenze tra polline «fresco» e polline acetolizzato.
Summary According to the program «Palynological Italian Flora», and continuing the study of the Italian Corylaceae, the palynological card ofCarpinus betulus L. is shown. The study is carried out on pollen coming from three different localities and regards both «fresh» and acetolyzed pollen. For each sample, measurements are carried out on 30 «fresh» pollen grains in glicerol jelly and on 30 acetolyzed pollen grains in water/glicerol 1/1; general observations regard 500 «fresh» and 500 acetolyzed pollen grain/sample. Some morphological observations on the aperture number/position and differencies between «fresh» and acetolized pollen are pointed out.
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82.
Previously it was demonstrated that thiopental in vivo anesthesia didn't affect the Na+/K(+)-ATPase activity of syncythiotrophoblast plasma membrane, while affecting other enzymatic activity. The aim of the present work was to investigate if this lack of effect of thiopental on the Na+/K+ ATPase activity might be due to its specificity of action on definite membrane proteins or if the binding sites of the anesthetic to this enzyme might be masked within the membrane. Temperature dependence of the Na+/K(+)-ATPase activity and of a spin label paramagnetic maleimide derivative (MSL,2,2,6,6-tetramethylpiperidin-1-oxyl-4-maleimide), which shows a selective binding to the reduced sulfhydryl groups of proteins were investigated. This report shows that a Na+/K(+)-ATPase membranous preparation obtained from placental tissue is strongly inhibited by thiopental.  相似文献   
83.
Aluminum (Al), oxidative stress and impaired cholinergic functions have all been related to Alzheimer's disease (AD). The present study evaluates the effect of aluminum on acetylcholinesterase (AChE) and lipid peroxidation in the mouse brain. Mice were loaded by gavage with Al 0.1 mmol/kg/day 5 days per week during 12 weeks. The mice were divided into four groups: (1) control; (2) 10 mg/mL of citrate solution; (3) 0.1 mmol/kg of Al solution; (4) 0.1 mmol/kg of Al plus 10 mg/mL of citrate solution. AChE activity was determined in the hippocampus, striatum, cortex, hypothalamus and cerebellum and lipid peroxidation was determined in the hippocampus, striatum and cortex. An increase of AChE activity was observed in the fourth group (Al + Ci) in the hippocampus (36%), striatum (54%), cortex (44%) and hypothalamus (22%) (p<0.01). The third group (Al) presented a decrease of AChE activity in the hypothalamus (20%) and an enhancement in the striatum (27%). Lipid peroxidation, measured by TBARS (thiobarbituric acid reactive substances), was elevated in the hippocampus and cerebral cortex when compared with the control (p < 0.01). The effect of aluminum on AChE activity may be due to a direct neurotoxic effect of the metal or perhaps a disarrangement of the plasmatic membrane caused by increased lipid peroxidation.  相似文献   
84.
Muscarinic cholinergic mechanisms play a key role in stimulating gastric pepsinogen secretion. Studies using antagonists suggested that the M3 receptor subtype (M3R) plays a prominent role in mediating pepsinogen secretion, but in situ hybridization indicated expression of M1 receptor (M1R) in rat chief cells. We used mice that were deficient in either the M1 (M1R-/-) or M3 (M3R-/-) receptor or that lacked both receptors (M(1/3)R-/-) to determine the role of M1R and M3R in mediating cholinergic agonist-induced pepsinogen secretion. Pepsinogen secretion from murine gastric glands was determined by adapting methods used for rabbit and rat stomach. In wild-type (WT) mice, maximal concentrations of carbachol and CCK caused a 3.0- and 2.5-fold increase in pepsinogen secretion, respectively. Maximal carbachol-induced secretion from M1R-/- mouse gastric glands was decreased by 25%. In contrast, there was only a slight decrease in carbachol potency and no change in efficacy when comparing M3R-/- with WT glands. To explore the possibility that both M1R and M3R are involved in carbachol-mediated pepsinogen secretion, we examined secretion from glands prepared from M(1/3)R-/- double-knockout mice. Strikingly, carbachol-induced pepsinogen secretion was nearly abolished in glands from M(1/3)R-/- mice, whereas CCK-induced secretion was not altered. In situ hybridization for murine M1R and M3R mRNA in gastric mucosa from WT mice revealed abundant signals for both receptor subtypes in the cytoplasm of chief cells. These data clearly indicate that, in gastric chief cells, a mixture of M1 and M3 receptors mediates cholinergic stimulation of pepsinogen secretion and that no other muscarinic receptor subtypes are involved in this activity. The development of a murine secretory model facilitates use of transgenic mice to investigate the regulation of pepsinogen secretion.  相似文献   
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Mild insulin resistance appears to be an early metabolic defect in girls with Turner syndrome (TS). Impaired glucose tolerance has been reported in 10-34% of patients with TS, and type 2 diabetes mellitus is 2-4 times more common and occurs at a younger age in girls with TS than in the general population. In a mixed longitudinal and cross-sectional study, we analysed carbohydrate tolerance and insulin sensitivity in 46 children and adolescents with TS who reached their final height after long-term treatment (mean 6.3 +/- 2.5 years) with growth hormone (GH: 0.33 mg/kg/week [0.05 mg/kg/day]), and in 36 of these patients who were followed-up after the cessation of GH therapy (mean follow-up, 2.6 +/- 2.5 years; range, 1-9.5 years). Patients with TS were compared with an age-matched female control group. Insulin sensitivity appeared to be lower in patients with TS than in controls, even before the start of GH therapy. As in controls, insulin sensitivity decreased with age in patients with TS, and levels were lower in those aged >12 years than in those aged <12 years. GH therapy resulted in good catch-up growth in patients with TS, with final height significantly higher than projected height evaluated before the initiation of GH therapy. Insulin sensitivity increased after 7-8 years of therapy and, on the cessation of GH therapy, returned to pre-treatment levels. The increase in insulin sensitivity seen on the cessation of GH therapy appeared to be influenced negatively by body mass index and triglyceride levels, and correlated positively with the number of years since cessation of GH therapy. As in the general population, excess weight and an abnormal lipid profile, in particular excess triglyceride levels, worsened insulin sensitivity. In conclusion, our study confirms that GH therapy reduces insulin sensitivity, but at its cessation there is a return to pre-therapy values. We therefore report a progressive improvement in carbohydrate tolerance and insulin function in patients with TS, despite an increase in age.  相似文献   
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89.
Previous studies have compared the immune systems of wild and of laboratory rodents in an effort to determine how laboratory rodents differ from their naturally occurring relatives. This comparison serves as an indicator of what sorts of changes might exist between modern humans living in Western culture compared to our hunter-gatherer ancestors. However, immunological experiments on wild-caught animals are difficult and potentially confounded by increased levels of stress in the captive animals. In this study, the humoral immune responses of laboratory rats in a traditional laboratory environment and in an environment with enriched biodiversity were examined following immunization with a panel of antigens. Biodiversity enrichment included colonization of the laboratory animals with helminths and co-housing the laboratory animals with wild-caught rats. Increased biodiversity did not apparently affect the IgE response to peanut antigens following immunization with those antigens. However, animals housed in the enriched biodiversity setting demonstrated an increased mean humoral response to T-independent and T-dependent antigens and increased levels of “natural” antibodies directed at a xenogeneic protein and at an autologous tissue extract that were not used as immunogens.  相似文献   
90.

Background

Bruxism is a parafunctional habit characterized by grinding and/or clenching of the teeth. It may happen while awake (awake bruxism) or while sleeping (sleep bruxism). In adults, the prevalence is 20% for the awake bruxism and 8% for the sleep bruxism. Peripheral, central, and psychosocial factors influence the disorder, which may predispose to pain in the masticatory muscles and neck, headache, decreased pain thresholds in the masticatory and cervical muscles, limitation mandibular range of motion, sleep disorders, stress, anxiety, depression, and overall impairment of oral health. The aim of this study is to compare two distinct physical therapy interventions with dental treatment in pain, mandibular range of motion, sleep quality, anxiety, stress, depression, and oral health in individuals with bruxism.

Methods/Design

Participants will be randomized into one of three groups: Group 1 (n?=?24) intervention will consist of massage and stretching exercises; Group 2 (n?=?24) will consist of relaxation and imagination therapies; and Group 3 (n?=?24) will receive dental treatment. The evaluations will be performed at baseline, immediately after treatment, and at 2-month follow-up. Pain intensity will be assessed using the visual analogical scale, while pain thresholds will be determined using dolorimetry. Mandibular range of motion will be assessed using digital pachymeter. Sleep quality will be assessed by the Pittsburgh Sleep Quality Index, anxiety by the State-Trait Anxiety Inventory, stress by the Perceived Stress Scale-10, depression by the Beck Depression Inventory, and oral health will be assessed using the Oral Health Impact Profile - 14. Significance level will be determined at the 5% level.

Discussion

This project describes the randomization method that will be used to compare two physical therapy interventions with dental treatment in the management of pain, mandibular range of motion, sleep quality, anxiety, stress, depression, and oral health in individuals with bruxism. The study will support the practice of evidence-based physical therapy for individuals with bruxism. Data will be published after study is completed.

Trial registration

ClinicalTrials.gov, NCT01778881  相似文献   
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