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991.
不同角度后倾曲对下颌第二磨牙作用力的三维有限元分析 总被引:1,自引:0,他引:1
目的:探讨0.018〞澳丝弯制的不同角度后倾曲对下颌第二磨牙作用力的情况。方法:应用CT扫描技术、Auto CAD及ANSYS相结合的建模程序,以中国人正常下颌骨为建模的实体参照,建立下颌第二磨牙及其牙周组织的三维有限元模型,同时建立用0.018〞澳丝弯制附5°、10°、15°、20°、25°、30°六个不同角度磨牙后倾曲唇弓的三维有限元模型,利用弯曲梁应变原理,计算出不同角度后倾曲作用下,下颌第二磨牙颊面管近中端及远中端力的大小及方向。结果:第二磨牙近中受到向伸长力,远中受到龈向压低力,其大小随着角度的增大而增大,近中力值大于远中力值。结论:后倾曲对第二磨牙产生远中倾斜力矩;随着后倾曲角度增大,磨牙呈现远中直立的趋势,同时牙冠舌向倾斜趋势加大。 相似文献
992.
J. R. Sa M. A. Alvarenga E. B. Rangel C. S. Melaragno A. M. Gonzalez M. M. Linhares A. Salzedas A. K. Carmona V. Tonetto-Fernandes M. A. Gabbay J. O. Medina Pestana S. A. Dib 《American journal of transplantation》2010,10(1):184-188
Diabetes mellitus with resistance to insulin administered subcutaneously or intramuscularly (DRIASM) is a rare syndrome and is usually treated with continuous intravenous insulin infusion. We present here two cases of DRIASM in 16 and 18 years female patients that were submitted to pancreas transplantation alone (PTA). Both were diagnosed with type 1 diabetes as young children and had labile glycemic control with recurrent episodes of diabetic ketoacidosis. They had prolonged periods of hospitalization and complications related to their central venous access. Exocrine and endocrine drainages were in the bladder and systemic, respectively. Both presented immediate graft function. In patient 1, enteric conversion was necessary due to reflux pancreatitis. Patient 2 developed mild postoperative hyperglycemia in spite of having normal pancreas allograft biopsy and that was attributed to her immunosuppressive regimen. Patient 1 died 9 months after PTA from septic shock related to pneumonia. In 8 months of follow-up, Patient 2 presented optimal glycemic control without the use of antidiabetic agents. In conclusion, PTA may be an alternative treatment for DRIASM patients. 相似文献
993.
目的探讨吡格列酮对脑缺血再灌注损伤家兔细胞凋亡的影响及其机制。方法40只雄性家兔随机分为5组:①假手术组(S组,n=8);②模型组(M组,n=8);③吡格列酮组(P组,n=8);(4)GW9662+吡格列酮组(GP组,n=8);(5)DMSO组(D组,n=8)。除S组外,其余各组均通过线栓法建立家兔大脑中动脉阻塞(MCAO)再灌注损伤模型。于术前30min分别给予相应处理。缺血120min再灌注24h后,对家兔进行神经功能评分;HE染色观察病理形态学。TUNEL检测神经细胞凋亡。结果①与S组比较,M组神经功能评分明显增加(P〈0.05);与M组比较,P组神经功能评分明显降低(P〈0.05)。②与S组比较,M组凋亡细胞明显增加(P〈0.05);与M组比较,P组凋亡细胞明显降低(P〈0.05)。结论吡格列酮可通过减轻形态学改变、抗神经细胞凋亡,对神经细胞发挥保护作用。 相似文献
994.
Ibuprofen-loaded polystyrene microparticles were prepared by the emulsionsolvent evaporation process from an aqueous system. The effects of different parameters on the drug content and on the release of the drug from the microparticles were investigated. The drug content, in all the formulations, was less than the theoretical drug loading. The lower drug content was due to drug partitioning to the external aqueous phase during formulation. Statistical analysis revealed that the variation in the concentrations of the emulsion stabilizer and the organic disperse phase volume did not significantly alter the release of the drug. Although an increase in drug loading increased drug release from the microparticles, a biphasic linear relationship was observed between the time required for 50% drug release and the drug loading. The effect of size of the microparticles on drug release was more important for the low drug-loaded microparticles than that for the high drug-loaded microparticles. Such release behaviour from the microparticles was explained on the basis of the morphological structure of the microparticles. 相似文献
995.
Peter Bytzer Anna Morocutti Peter Kennerly Miroslav Ravic Neil Miller ON BEHALF OF THE ROSE TRIAL INVESTIGATORS 《Scandinavian journal of gastroenterology》2013,48(10):1132-1140
Objective. Gastro-oesophageal reflux disease (GORD) symptoms have a significant impact on patients’ well-being. Onset of symptom relief is therefore an important consideration in GORD treatment. The primary objective was to compare the efficacy of rabeprazole (20?mg) and omeprazole (20?mg) regarding onset of heartburn control during the first 7 days of treatment in patients with erosive oesophagitis. Secondary objectives included maintenance of sustained heartburn control, control of other GORD symptoms (e.g. acid regurgitation, epigastric pain, dysphagia), effect on quality of life, patient satisfaction with treatment, and adverse events. Material and methods. In this multicentre, randomized, parallel-group, double-blind, comparative study, performed in Europe and Iceland, patients with endoscopically confirmed erosive oesophagitis were randomized to receive once-daily treatment with rabeprazole 20?mg (n=358) or omeprazole 20?mg (n=359) for 7 days. Symptoms were recorded (scored on a 5-point Likert scale) twice daily by the patients on their diary cards. Results. Median time to reach heartburn control was 1.5 days for both the rabeprazole and omeprazole groups (p<0.43). The results were similar between treatments for other study parameters. Both treatments were well tolerated. Conclusions. Unlike previous studies, no significant differences were found between treatments with rabeprazole (20?mg) and omeprazole (20?mg) in this study. Further studies are needed to evaluate the potential benefit of fast-acting proton-pump inhibitors, such as rabeprazole, with respect to onset of symptom control in erosive GORD. 相似文献
996.
RATIONALE: Puerto Ricans have the highest prevalence of asthma among all ethnic groups in the United States. There have been no studies that directly compare the burden of asthma between Puerto Ricans living in Puerto Rico and those living in the mainland United States. OBJECTIVE: To examine the relation between birthplace, area of residence, and asthma in Puerto Rican children. METHODS: Multistage population-based probability sample of children in the San Juan and Caguas metropolitan areas in Puerto Rico and in the Bronx, NY. Information was collected in a household survey of 2,491 children and their primary caretakers. RESULTS: The overall prevalence of asthma among Puerto Rican children in this study was very high (38.6%). Although children from Puerto Rico had higher socioeconomic status and lower rates of premature birth and prenatal smoke exposure, the prevalence of lifetime asthma was higher in Puerto Rican children living in Puerto Rico than in Puerto Rican children living in the South Bronx (41.3% vs 35.3%, p = 0.01). In multivariable analysis, residence in Puerto Rico was associated with increased odds of lifetime asthma (odds ratio [OR], 1.27; 95% confidence interval [CI], 1.03 to 1.57) and lifetime hospitalization for asthma (OR, 1.47; 95% CI, 1.04-2.07). CONCLUSIONS: Puerto Rican children in Puerto Rico had a higher risk of asthma than Puerto Rican children in the South Bronx, highlighting the need for further examination of the roles of migration, acculturation, and environmental and psychosocial factors on the development of asthma in this high-risk population. 相似文献
997.
Kisspeptin synchronizes preovulatory surges in cyclical ewes and causes ovulation in seasonally acyclic ewes 总被引:3,自引:0,他引:3
Caraty A Smith JT Lomet D Ben Saïd S Morrissey A Cognie J Doughton B Baril G Briant C Clarke IJ 《Endocrinology》2007,148(11):5258-5267
We determined whether kisspeptin could be used to manipulate the gonadotropin axis and ovulation in sheep. First, a series of experiments was performed to determine the gonadotropic responses to different modes and doses of kisspeptin administration during the anestrous season using estradiol-treated ovariectomized ewes. We found that: 1) injections (iv) of doses as low as 6 nmol human C-terminal Kiss1 decapeptide elevate plasma LH and FSH levels, 2) murine C-terminal Kiss1 decapeptide was equipotent to human C-terminal Kiss1 decapeptide in terms of the release of LH or FSH, and 3) constant iv infusion of kisspeptin induced a sustained release of LH and FSH over a number of hours. During the breeding season and in progesterone-synchronized cyclical ewes, constant iv infusion of murine C-terminal Kiss1 decapeptide-10 (0.48 mumol/h over 8 h) was administered 30 h after withdrawal of a progesterone priming period, and surge responses in LH occurred within 2 h. Thus, the treatment synchronized preovulatory LH surges, whereas the surges in vehicle-infused controls were later and more widely dispersed. During the anestrous season, we conducted experiments to determine whether kisspeptin treatment could cause ovulation. Infusion (iv) of 12.4 nmol/h kisspeptin for either 30 or 48 h caused ovulation in more than 80% of kisspeptin-treated animals, whereas less than 20% of control animals ovulated. Our results indicate that systemic delivery of kisspeptin provides new strategies for the manipulation of the gonadotropin secretion and can cause ovulation in noncyclical females. 相似文献
998.
Genetic study of variation in normal mouse iron homeostasis reveals ceruloplasmin as an HFE-hemochromatosis modifier gene 总被引:4,自引:0,他引:4
Gouya L Muzeau F Robreau AM Letteron P Couchi E Lyoumi S Deybach JC Puy H Fleming R Demant P Beaumont C Grandchamp B 《Gastroenterology》2007,132(2):679-686
BACKGROUND & AIMS: Genetic hemochromatosis is one of the most common genetic disorders, with progressive tissue iron overload leading to severe clinical complications. In Northern European populations, genetic hemochromatosis is usually caused by homozygosity for the C282Y mutation in the HFE protein. However, penetrance of this mutation is incomplete, suggesting that other genetic and environmental factors contribute to its differential biologic or clinical expression. METHODS: To identify genes modifying iron homeostasis, we screened the 27 recombinant congenic strains of the C3H/DiSnA-C57BL/10ScSnA/Dem series for tissue and serum iron indices and genotyped 18 microsatellite markers in (C3H/DiSnA x HcB-2) F2 hybrid mice. RESULTS: We identified 1 locus encompassing the Ceruloplasmin (Cp) gene with a strong linkage with liver iron, serum iron, and transferrin levels but not with spleen iron. Sequencing of Cp showed an R435X nonsense mutation in exon 7 in C3H/DiSnA mice. To evaluate whether Cp might act as a modifier gene of genetic hemochromatosis, we intercrossed C3H Hfe(-/-) and C3HDiSnA Cp(R435X/R435X) mice. As expected, we found that double-mutant mice deposited more iron in the liver than mice defective for either one or both genes. In contrast, Hfe(-/-) x Cp(R435/R435X) or Cp(R435X/R435X) x Hfe(+/-) showed 30% decrease in liver iron when compared with single mutant mice. CONCLUSIONS: This study highlights the existence of complex interactions between Cp and HFE and represents the first example of a modifier gene with a protective effect, in which heterozygosity reduces the iron load in the context of HFE deficiency. 相似文献
999.
1000.