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141.
Forty-four normotensive females, who were selected on the basis of lower prevailing potassium intake, participated in a two-period crossover study to assess the effects of potassium supplementation on blood pressure. They were randomly allocated to one of two groups who took either 80 mmol/day of KCl (Slow-K, Ciba Geigy), or matching placebo, for the first of two 4-week treatment periods. The treatments were reversed during the second 4-week period. Despite significant increases in both urinary and plasma potassium no consistent fall in blood pressure was seen during 80 mmol/day potassium intake.  相似文献   
142.
Transgenic (TG) mice deficient in glucocorticoid receptors (GR) were used in order to study the effects of a reduced GR function on adrenocorticotropin hormone and corticosterone plasma levels and on serotonin metabolism in different brain areas under basal resting conditions, after a 30-min restraint stress and 60 min after the end of the restraint stress. There was no difference in basal or stress-induced levels of either adrenocorticotropin hormone or corticosterone in control and TG mice, but the return of adrenocorticotropin hormone to basal values after the end of the stress was delayed in TG mice. Under basal conditions, the ratio 5-hydroxyindoleacetic acid/5-hydroxytryptamine was decreased only in the hippocampus of TG mice compared to controls. In the brain stem, the ratio 5-hydroxyindoleacetic acid/5-hydroxytryptamine increased compared to basal values after a 30-min restraint stress and values were still high 60 min after the end of the restraint stress in both control and TG mice. In the hippocampus, the ratio 5-hydroxyindoleacetic acid/5-hydroxytryptamine increased at the end of the stress and returned to basal levels 60 min later in control mice, whereas there was no change at the end of the stress but an increase 60 min later in TG mice. Finally there was no change in serotonin metabolism in the cortex, striatum or hypothalamus in either group or situation. Our results support the hypothesis of a tonic activation of serotonin turnover by corticosterone through GR in the mouse hippocampus. Moreover, stress-induced stimulation of serotonin metabolism in the brain stem and hippocampus appears to be delayed in TG mice compared to control mice. These results are particularly relevant for mood disorders such as depression where alterations of serotoninergic transmission might be secondary to an impairment of GR functions.  相似文献   
143.
An assay for the binding of [(3)H]thyrotropin-releasing hormone ([(3)H]TRH) is described. Plasma membranes isolated from bovine anterior pituitary gland bind about 600 femtomoles of this hormone per mg of protein, as compared to 15 femtomoles per mg of protein in the total adenohypophyseal homogenate (40-fold purification). The equilibrium constant of membrane receptor-[(3)H]TRH binding at 0 degrees C is 4.3 x 10(7) L.M(-1), or a half-maximal binding of this hormone at 23 nM. The binding is time-dependent; addition of unlabeled hormone induces dissociation of the receptor-[(3)H]TRH complex with a half-life of 14 min. The binding of TRH is not altered by 10 muM melanocyte-stimulating hormone-release inhibiting hormone, lysine-vasopressin, adrenocorticotropin, growth hormone, prolactin, luteinizing hormone, insulin, glucagon, L-thyroxine, or L-triiodothyronine. K(+) and Mg(++) increase formation of the receptor-TRH complex at optimal concentrations of 5-25 mM and 0.5-2.5 mM, respectively, with inhibition at higher concentrations. Ca(++) inhibits binding of TRH at all concentrations tested.  相似文献   
144.
RATIONALE: We hypothesized that the epithelial reticular basement membrane (RBM) thickening and eosinophilic inflammation characteristic of asthma would be present in symptomatic infants with reversible airflow obstruction. METHODS: RBM thickness and numbers of inflammatory cells were determined in ultrathin sections of endobronchial biopsies obtained from 53 infants during clinical bronchoscopy for severe wheeze and/or cough. Group A: 16 infants with a median age of 12 months (range 3.4-26 months), with decreased specific airway conductance (sGaw) and bronchodilator reversibility; Group B: 22 infants with a median age of 12.4 months (5.1-25.9 months), with decreased sGaw but without bronchodilator reversibility; and Group C: 15 infants with a median age of 11.5 months (3.4-24.3 months) with normal sGaw. Additional comparisons were made with the following groups. Group D: 17 children, median age 10.3 years (6-16 years), with difficult asthma; Group E: 10 pediatric control subjects without asthma, median age 10 years (6-16 years); and Group F: nine adult normal, healthy control subjects, median age 27 years (21-42 years). MAIN RESULTS: There were no significant differences in RBM thickness or inflammatory cell number between the infant groups. RBM thickness was similar in the infants and Groups E and F. However, the RBM in all infant groups (Group A: median 4.3 microm [range 2.8-9.2 microm]; Group B: median 4.15 microm [range 2.7-5.8 microm]; Group C: median 3.8 microm [range 2.7-5.5 microm]) was significantly less thick than that in the older children with asthma (Group D: median 8.3 microm [range 5.3-12.7 microm]; p < 0.001). CONCLUSION: RBM thickening and the eosinophilic inflammation characteristic of asthma in older children and adults are not present in symptomatic infants with reversible airflow obstruction, even in the presence of atopy.  相似文献   
145.
Fifty-nine healthy omnivores volunteered for a randomized crossover trial with a lacto-ovo-vegetarian (L-O-V) diet. Twenty-one 1-day diet records were kept throughout the project as a means of assessing food and nutrient intakes, and samples of serum and urine were assayed to evaluate change in prostanoid metabolism. While on the L-O-V diet subjects ate more vegetable protein, wholegrain cereals, polyunsaturated oils, fruits and vegetables, and avoided eating meat, fish or poultry. The L-O-V diet contained significantly more polyunsaturated fatty acids, fibre, vitamin C, vitamin E, magnesium, calcium and potassium, and less total protein, saturated fat, monounsaturated fat and vitamin B12 than the control omnivore diet. Changes in nutrient intakes were subjected to principal components analysis to identify dimensions of change in nutrient intakes. Three Factors accounted for 83% of the total variation in dietary intake. Blood pressure changes were significantly and negatively (F = 17.4, P less than 0.001 for systolic; F = 6.09, P = 0.02 for diastolic pressure) related to individual scores for only one Factor--that representing an increase in intake of polyunsaturated fat, fibre, vitamin C, vitamin E, calcium and magnesium, and a fall in intake of protein and vitamin B12. Blood pressure changes were unrelated to change in body weight or sodium intake. Serum and urinary prostanoids were not affected by eating the L-O-V diet.  相似文献   
146.

Purpose

Bone loss following extraction is maximum in horizontal dimension. Height is also reduced which is pronounced on the buccal aspect. Various surgical procedures are available to correct the bone volume viz. GBR, onlay bone grafting, alveolar distraction and sandwich osteotomy. Sandwich osteotomy has been found to increase the vertical alveolar bone height successfully.

Objectives

The objective of the study was to assess the effect of alveolar segmental sandwich osteotomy on alveolar height and crestal width.

Materials and Methodology

A prospective study was undertaken from December 2012 to August 2014. Seven patients with 12 implant sites with a mean age of 36 years were recruited. All seven patients with 12 implant sites underwent alveolar segmental sandwich osteotomy and interpositional bone grafting. Alveolar bone height was assessed radiographically preoperatively, immediate post-op, and at 3 months post-op. Alveolar bone width was assessed radiographically preoperatively and at 3 months post-op. Statistical significance was inferred at p < 0.05.

Results

The mean vertical augmentation at immediate post-op was 6.58 mm (p = 0.001). The vertical augmentation that was achieved 3 months post-op was a mean of 3.75 mm which was statistically significant (p = 0.004). The change in alveolar height from immediate post-op to 3 month post-op was a mean 1.69 mm. The mean change in alveolar crestal width at 3 months was a mean of ?0.29 mm (p = 0.57).

Conclusion

Sandwich osteotomy can be used as an alternative technique to increase alveolar bone height prior to implant placement. Moderate alveolar deficiency can be predictably corrected by this technique.
  相似文献   
147.
The growth and maturity of the peripheral immune system and subsequent development of pulmonary immunity in early life is dictated by host, environmental and microbial factors. Dysregulation during the critical window of immune development in the postnatal years results in disease which impacts on lifelong lung health. Asthma is a common disease in childhood and is often preceded by wheezing illnesses during the preschool years. However, the mechanisms underlying development of wheeze and how and why only some children progress to asthma is unknown. Human studies to date have generally focused on peripheral immune development, with little assessment of local tissue pathology in young children. Moreover, mechanisms underlying the interactions between inflammation and tissue repair at mucosal surfaces in early life remain unknown. Disappointingly, mechanistic studies in mice have predominantly used adult models. This review will consider the aspects of the neonatal immune system which might contribute to the development of early life wheezing disorders and asthma, and discuss the external environmental factors which may influence this process.  相似文献   
148.
A positive relationship between alcohol consumption and blood pressure (BP) is well-established but the relative effect of specific alcoholic beverages is controversial. This study aimed to determine whether red wine may improve vascular function and have less of an impact on blood pressure because of its high content of antioxidant vasodilator polyphenolic compounds. Healthy normotensive men entered a 4-period crossover study comparing in random order 4 weeks of control-abstinence with similar periods of daily consumption of red wine (375 mL; 39 grams alcohol), de-alcoholized red wine (375 mL), or beer (1125 mL; 41 grams alcohol). Ambulatory systolic BP and diastolic BP and heart rate (HR) were measured together with vascular function as assessed by flow-mediated dilatation (FMD) and glyceryl trinitrate-mediated (GTNMD) dilatation of the brachial artery. The systolic and diastolic BP and HR were not different between control-abstinence and de-alcoholized red wine. However, compared with control-abstinence, both red wine and beer increased awake systolic BP (2.9 and 1.9 mm Hg, respectively; P<0.05) and asleep HR (5.0 and 4.4 bpm; P<0.05). There were no specific effects of red wine, de-alcoholized red wine, or beer on FMD or GTNMD. Daily consumption of approximately 40 grams alcohol as either red wine or beer for 4 weeks results in similar increases in systolic BP and HR. De-alcoholized red wine did not lower BP, and neither red wine nor de-alcoholized red wine influenced vascular function, suggesting that red wine polyphenolics do not have a significant role in mitigating the blood pressure-elevating effects of alcohol in men.  相似文献   
149.
This retrospective study compared the clinical outcomes of negative pressure wound therapy with reticulated open cell foam (NPWT/ROCF) as delivered by Vacuum‐Assisted Therapy® (V.A.C.® Therapy, KCI Licensing Inc., San Antonio, TX) to non‐NPWT/ROCF conventional therapy (CT) in split‐thickness skin graft (STSG) survival in all patients to determine whether NPWT/ROCF affects the outcome of the graft survival, in terms of overall graft take, duration of graft take, repeated grafts and complications. The authors conducted a 10‐year retrospective review of 142 patients admitted to a level I trauma centre and treated with an STSG in foot and ankle reconstructive surgeries. Demographic data, wound etiology, dressing type used, time to graft take, NPWT/ROCF duration, complications and outpatient treatments were analysed. There were significantly fewer repeated STSGs required in the NPWT/ROCF group compared to CT [n = 3 (3·5%) versus n = 9 (16%); P = 0·006]. In assessing safety, there were fewer complications in graft failure (seroma, hematoma and infection) in the NPWT/ROCF group as compared to the CT group at 8·9 months (range: 1–12 months). NPWT/ROCF is an excellent alternative for securing an STSG and is associated with improved graft survival as measured by a reduction in the number of repeated STSGs and graft failure complications.  相似文献   
150.
BACKGROUND: Studies on airway remodeling in children with cystic fibrosis (CF) may be hampered by difficulty in obtaining evaluable endobronchial biopsy specimens because of large amounts of mucus and inflammation in the CF airway. We prospectively assessed how the quality of biopsy specimens obtained from children with CF compare with those from children with other airway diseases. METHODS: Fiberoptic bronchoscopy with endobronchial biopsy was performed in 67 CF children (age range, 0.2 to 16.8 years), 34 children with wheeze/asthma (W/A), and 64 control children with chronic respiratory symptoms. Up to three biopsy specimens were taken and stained with hematoxylin and eosin. Biopsy specimen size and structural composition were quantified using stereology. RESULTS: At least one evaluable biopsy specimen was obtained in 72% of CF children, in 79% of children with W/A, and in 72% of control subjects (difference was not significant). The use of large biopsy forceps (2.0 mm) rather than small biopsy forceps (1.0 mm) [odds ratio (OR), 5.8; 95% confidence interval (CI), 1.1 to 29.8; p = 0.037] and the number of biopsy specimens taken (odds ratio, 2.6; 95% confidence interval, 1.3 to 5.2; p = 0.006) significantly contributed to the success rate. Biopsy size and composition were similar between groups, except that CF children and those patients with W/A had a higher percentage of the biopsy specimen composed of muscle than did control subjects (median 6.2% and 9.7% vs 0.9%, respectively; p = 0.002). CONCLUSIONS: Biopsy size and quality are adequate for the study of airway remodeling in CF children as young as 2 months of age. Researchers should use large forceps when possible and take at least two biopsy specimens per patient. An increased airway smooth muscle content of the airway mucosa may contribute to the pathophysiology of CF lung disease.  相似文献   
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