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81.
Tetsuo Ichikawa  DDS  PhD    Osamu Ishida  DT    Megumi Watanabe  DDS  PhD    Yoritoi Tomotake  DDS  PhD    Hua Wei  DDS  PhD    & Chen Jianrong  DDS  PhD 《Journal of prosthodontics》2008,17(6):487-489
This article discusses two methods for improving the retrievability of cement-retained implant superstructures. One method involves incorporating a removal screw in the superstructure and the second method uses a small dimple on the abutment, accessed through a vent in the superstructure.  相似文献   
82.
BACKGROUND: Activin A is a member of the transforming growth factor-beta superfamily which is directly implicated in airway structural change and inflammation in asthma. In vitro, the biological effects of activin A are neutralized by the soluble binding protein follistatin. OBJECTIVE: To determine the potential of endogenous follistatin to suppress activin A in vivo by analysing their relative tissue and kinetic compartmentalization during the effector phase of subchronic Th2-driven mucosal inflammation in a murine model of allergic asthma. METHODS: Eosinophilic mucosal inflammation was elicited by triggering Th2 recall responses by antigen challenge in ovalbumin-sensitized BALB/c mice. The kinetics and distribution of activin A and follistatin protein were assessed in lung tissue and bronchoalveolar lavage fluid and measured in relation to airway eosinophilia, goblet cell metaplasia and Th2 cytokine production in mediastinal lymph nodes. RESULTS: Follistatin was released concurrently with activin A suggesting it acts as an endogenous regulator: peak BAL concentrations coincided with maximal airway eosinophilia, and frequency of IL-4, IL-5 and IL-13 producing cells in mediastinal lymph nodes but induction lagged behind the onset of inflammation. Follistatin and activin A immunoreactivity were lost in airway epithelial cells in parallel with goblet cell metaplasia. Exogenous follistatin inhibited the allergen-specific Th2 immune response in mediastinal lymph nodes and mucus production in the lung. CONCLUSION: Follistatin is preformed in the normal lung and released in concert with activin A suggesting it serves as an endogenous regulator. Disturbance of the fine balance between activin A and its endogenous inhibitor follistatin may be a determinant of the severity of allergic inflammation or tissue phenotypic shift in asthma.  相似文献   
83.
BACKGROUND: Identification of preoperative predictors of weight loss after laparoscopic Roux-en-Y gastric bypass (LRYGB) can lead to improved clinical outcomes. The purpose of this study was to determine whether preoperative weight loss was associated with improved percentage of excess weight loss (%EWL) 1 year after LRYGB. METHODS: A retrospective analysis was performed on the data from 295 patients who had undergone LRYGB at our institution from July 2004 to November 2005. Routine preoperative weight loss goals were implemented to facilitate the laparoscopic approach and ensure compliance with an appropriate nutritional and exercise program. Patients with an initial consultation BMI of <50, 50-59, and > or =60 kg/m(2) were given weight loss goals of 5 lb and 5% and 10% of body weight, respectively. RESULTS: The mean age was 45 +/- 10 years, and 89% were women and 70% were white. The mean BMI at the initial consultation was 51 +/- 7 kg/m(2). A significant inverse correlation was found between the preoperative BMI and %EWL at 1 year postoperative (P <.001). When controlling for BMI, no correlation was found between the %EWL and percentage of preoperative weight loss or attainment of the weight loss goals. The weight loss goals were met or surpassed by 79% of patients, and the mean %EWL at 1 year was 66%. Whites had greater %EWL at 1 year postoperatively compared with African Americans (67% versus 61%; P = .002). When controlling for age, gender, race, and consultation BMI, the preoperative weight loss did not predict for the %EWL at 1 year. CONCLUSION: The results of this study have shown that preoperative weight loss does not predict postoperative weight loss 1 year after LRYGB. A lower BMI, younger age, and white race predicted better %EWL.  相似文献   
84.
Two cases of leukaemic transformation are reported, one to acute lymphoblastic leukaemia associated with a 14q+ marker chromosome and the other to acute monocytic leukaemia, occurring 20 and 30 years, respectively, after the original diagnosis was made.  相似文献   
85.
The effects of single oral doses of bucindolol (50, 100, 200 and 400 mg), pindolol (10 mg), propranolol (160 mg) and placebo on arterial pressure and heart rate in the supine and standing positions and exercise heart rate were compared in 12 healthy male volunteers. Supine heart rate was significantly greater after all four doses of bucindolol and pindolol in comparison to propranolol. Bucindolol had no significant effect on standing heart rate which was significantly reduced by pindolol and propranolol. Bucindolol, pindolol and propranolol significantly reduced an exercise tachycardia for at least 24 h after drug administration. Supine systolic pressure was not affected by any treatment but supine diastolic pressure was significantly reduced by bucindolol (200 and 400 mg) and by pindolol. All doses of bucindolol, propranolol and pindolol significantly reduced standing systolic blood pressure. There was a significant linear trend for reductions in standing systolic blood pressure and increasing doses of bucindolol. Standing diastolic blood pressure was significantly reduced by bucindolol 200 and 400 mg. Faintness and light headedness occurred in 6 of 12 subjects after 200 mg bucindolol and in 8 of 10 subjects after 400 bucindolol. After bucindolol, analysis of plasma samples demonstrated the presence of bucindolol, 5-hydroxy and 6-hydroxy bucindolol and indolyl-t-butylamine. These observations indicate that in man, bucindolol is a beta-adrenoceptor blocking drug with hypotensive activity and probably partial agonist activity. It is unlikely that the hypotensive effects result from blockade of beta-adrenoceptors or from the drug's partial agonist activity.  相似文献   
86.
In women there is a gradual rise in the basal level of follicle stimulating hormone (FSH) in the years prior to the menopause (pre- menopause) which is thought to be due to a relative lack of ovarian factors reflecting the number of antral follicles present in the ovaries. Experimental animal models for this phenomenon, particularly in mono-ovulatory species, have been lacking due to most animals' relatively short life span. We have available a group of experimental ewes in which the right ovary was removed and the left ovary was autotransplanted to the neck at least 10 years previously, which have been maintained in good health until an age of 12-13 years. Two experiments were conducted with these animals to determine the endocrine and follicular effects of age: a retrospective experiment in the same Finn-Merino ewes (n = 5) when the animals were 6-7 or 12-13 years of age; and a cohort experiment in old (12-13 years, n = 6) and young (2 years, n = 5) ewes of the same breed. In both retrospective and cohort experiments, the concentrations of FSH were significantly higher (P < 0.05) in older animals during the luteal phase when oestradiol secretion was low. This increase in FSH was associated with a decrease in the concentration of inhibin A (P < 0.05) in older animals in both the follicular and luteal stages of the cycle but the concentrations of oestradiol were similar between ages. Although there were significantly fewer antral follicles (P < 0.05) available for development in older ewes during the early luteal phase of the cycle, the ovulation rate was similar to that observed in younger animals (2.0+/-0 vs 2.0+/-4; P > 0.05) but the interval from luteal regression to the onset of the LH surge was longer (P < 0.05) in older animals. In conclusion, the endocrine changes associated with increasing reproductive age in sheep are therefore similar to those observed in women, suggesting that the sheep could be a useful animal model to study the effect of age on human fertility.   相似文献   
87.
Three patients were found to have visual field defects which involved homonymous horizontal sectors of the visual fields, thus mimicking field defects associated with lesions of the lateral geniculate nucleus. Computed tomography provided anatomical evidence that the responsible lesion involved the optic radiations rather than the lateral geniculate nucleus.  相似文献   
88.
International Salmonella Typhimurium DT104 infections, 1992-2001   总被引:2,自引:0,他引:2  
The incidence of multidrug-resistant (MDR) Salmonella Typhimurium infections in humans, and in particular MDR definitive phage type 104 (DT104), has increased substantially in many countries in the last 2 decades, often associated with increased illness. To examine the magnitude of this problem, a survey was conducted among countries with available antimicrobial resistance or phage typing surveillance data. A total of 29, primarily industrialized, countries participated in the survey, which covered the years 1992-2001. Overall, the incidence of MDR S. Typhimurium and DT104 increased continuously during this period, although the problem affected primarily Europe and North America. The increase appeared to have peaked in the United Kingdom but not in other countries. Also, the incidence of quinolone-resistant S. Typhimurium was increasing. This survey implies that MDR S. Typhimurium constitutes an increasing public health problem in large parts of the world and emphasizes the importance of surveillance and control programs.  相似文献   
89.
Sets of five photographs of faces and sets of five nonsense syllables were presented visually to hearing and deaf children. In one experiment sequential presentation of items was in five windows, and was arranged in such a way that the presentation was incongruent with a left to right order. In a second experiment all items were presented successively at the same location. After the presentation of a set of items, subjects were shown two of the set which had been temporally adjacent, and were asked which had come before the other. In both experiments hearing subjects remembered temporal order better for nonsense syllables than for faces but deaf children remembered the order of faces better than the order of syllables. The results suggest that information about sequential order can be retained in a post-iconic visual store independently of spatial cues.  相似文献   
90.
HLA antigens and uveitis.   总被引:6,自引:5,他引:1       下载免费PDF全文
We have studied the antigen frequencies in a group of adult patients with acute and chronic iridocyclitis and chronic, cyclitis. In patients with iridocyclitis a statistically significant increased incidence of HLA-B27 was noted, even in those patients without joint or systemic disease. Patients with chronic iridocyclitis also were noted to have an increased incidence of B27; however, those patients with chronic cyclitis did not. On the basis of HLA-B27 studies there appears to be a fundamental difference between adult and juvenile iridocyclitis.  相似文献   
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