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排序方式: 共有4132条查询结果,搜索用时 15 毫秒
91.
Antonio Eduardo Monteiro de Almeida Ricardo Stein Miguel Gus Jo?o Agnaldo Nascimento Karlyse Claudino Belli Jorge Rene Garcia Arévalo Flávio Dani Fuchs Jorge Pinto Ribeiro 《Arquivos brasileiros de cardiologia》2014,103(4):338-347
Background
The importance of measuring blood pressure before morning micturition and in the afternoon, while working, is yet to be established in relation to the accuracy of home blood pressure monitoring (HBPM). Objective: To compare two HBPM protocols, considering 24-hour ambulatory blood pressure monitoring (wakefulness ABPM) as gold-standard and measurements taken before morning micturition (BM) and in the afternoon (AM), for the best diagnosis of systemic arterial hypertension (SAH), and their association with prognostic markers.Methods
After undergoing 24-hour wakefulness ABPM, 158 participants (84 women) were randomized for 3- or 5-day HBPM. Two variations of the 3-day protocol were considered: with measurements taken before morning micturition and in the afternoon (BM+AM); and with post-morning-micturition and evening measurements (PM+EM). All patients underwent echocardiography (for left ventricular hypertrophy - LVH) and urinary albumin measurement (for microalbuminuria - MAU).Result
Kappa statistic for the diagnosis of SAH between wakefulness-ABPM and standard 3-day HBPM, 3-day HBPM (BM+AM) and (PM+EM), and 5-day HBPM were 0.660, 0.638, 0.348 and 0.387, respectively. The values of sensitivity of (BM+AM) versus (PM+EM) were 82.6% × 71%, respectively, and of specificity, 84.8% × 74%, respectively. The positive and negative predictive values were 69.1% × 40% and 92.2% × 91.2%, respectively. The comparisons of intraclass correlations for the diagnosis of LVH and MAU between (BM+AM) and (PM+EM) were 0.782 × 0.474 and 0.511 × 0.276, respectively.Conclusions
The 3 day-HBPM protocol including measurements taken before morning micturition and during work in the afternoon showed the best agreement with SAH diagnosis and the best association with prognostic markers. 相似文献92.
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95.
Nils Schweingruber Henrike J. Fischer Lisa Fischer Jens van den Brandt Anna Karabinskaya Verena Labi Andreas Villunger Benedikt Kretzschmar Peter Huppke Mikael Simons Jan P. Tuckermann Alexander Flügel Fred Lühder Holger M. Reichardt 《Acta neuropathologica》2014,127(5):713-729
Glucocorticoids (GCs) are the standard therapy for treating multiple sclerosis (MS) patients suffering from an acute relapse. One of the main mechanisms of GC action is held to be the induction of T cell apoptosis leading to reduced lymphocyte infiltration into the CNS, yet our analysis of experimental autoimmune encephalomyelitis (EAE) in three different strains of genetically manipulated mice has revealed that the induction of T cell apoptosis is not essential for the therapeutic efficacy of GCs. Instead, we identified the redirection of T cell migration in response to chemokines as a new therapeutic principle of GC action. GCs inhibited the migration of T cells towards CCL19 while they enhanced their responsiveness towards CXCL12. Importantly, blocking CXCR4 signaling in vivo by applying Plerixafor® strongly impaired the capacity of GCs to interfere with EAE, as revealed by an aggravated disease course, more pronounced CNS infiltration and a more dispersed distribution of the infiltrating T cells throughout the parenchyma. Our observation that T cells lacking the GC receptor were refractory to CXCL12 further underscores the importance of this pathway for the treatment of EAE by GCs. Importantly, methylprednisolone pulse therapy strongly increased the capacity of peripheral blood T cells from MS patients of different subtypes to migrate towards CXCL12. This indicates that modulation of T cell migration is an important mechanistic principle responsible for the efficacy of high-dose GC therapy not only of EAE but also of MS. 相似文献
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AM Hempel S Cantlay V Molle SB Wang MJ Naldrett JL Parker DM Richards YG Jung MJ Buttner K Flärdh 《Proceedings of the National Academy of Sciences of the United States of America》2012,109(35):E2371-E2379
In cells that exhibit apical growth, mechanisms that regulate cell polarity are crucial for determination of cellular shape and for the adaptation of growth to intrinsic and extrinsic cues. Broadly conserved pathways control cell polarity in eukaryotes, but less is known about polarly growing prokaryotes. An evolutionarily ancient form of apical growth is found in the filamentous bacteria Streptomyces, and is directed by a polarisome-like complex involving the essential protein DivIVA. We report here that this bacterial polarization machinery is regulated by a eukaryotic-type Ser/Thr protein kinase, AfsK, which localizes to hyphal tips and phosphorylates DivIVA. During normal growth, AfsK regulates hyphal branching by modulating branch-site selection and some aspect of the underlying polarisome-splitting mechanism that controls branching of Streptomyces hyphae. Further, AfsK is activated by signals generated by the arrest of cell wall synthesis and directly communicates this to the polarisome by hyperphosphorylating DivIVA. Induction of high levels of DivIVA phosphorylation by using a constitutively active mutant AfsK causes disassembly of apical polarisomes, followed by establishment of multiple hyphal branches elsewhere in the cell, revealing a profound impact of this kinase on growth polarity. The function of AfsK is reminiscent of the phoshorylation of polarity proteins and polarisome components by Ser/Thr protein kinases in eukaryotes. 相似文献
98.
Rossi F Botticelli D Pantani F Pereira FP Salata LA Lang NP 《Clinical oral implants research》2012,23(1):41-48
Objective: To describe the healing of marginal defects below or above 1 mm of dimension around submerged implants in a dog model. Material and methods: In 12 Labrador dogs, all mandibular premolars and first molars were extracted bilaterally. After 3 months of healing, full‐thickness flaps were elevated in the edentulous region of the right side of the mandible. Two recipient sites were prepared and the marginal 5 mm were widened to such an extent to obtain, after implant installation, a marginal gap of 0.5 mm at the mesial site (small defect) and of 1.25 mm at the distal site (large defect). Titanium healing caps were affixed to the implants and the flaps were sutured allowing a fully submerged healing. The experimental procedures were subsequently performed in the left side of the mandible. The timing of the experiments and sacrifices were planned in such a way to obtain biopsies representing the healing after 5, 10, 20 and 30 days. Ground sections were prepared and histomorphometrically analyzed. Results: The filling of the defect with newly formed bone was incomplete after 1 month of healing in all specimens. Bone formation occurred from the base and the lateral walls of the defects. A larger volume of new bone was formed in the large compared with the small defects. Most of the new bone at the large defect was formed between the 10‐ and the 20‐day period of healing. After 1 month of healing, the outline of the newly formed bone was, however, located at a similar distance from the implant surface (about 0.4 mm) at both defect types. Only minor newly formed bone in contact with the implant, starting from the base of the defects, was seen at the large defects (about 0.8 mm) while a larger amount was detected at the small defects (about 2.2 mm). Conclusion: Marginal defects around titanium implants appeared to regenerate in 20–30 days by means of a distance osteogenesis. The bone fill of the defects was, however, incomplete after 1 month. To cite this article: Rossi F, Botticelli D, Pantani F, Pereira FP, Salata LA, Lang NP. Bone healing pattern in surgically created circumferential defects around submerged implants: an experimental study in dog.Clin. Oral Impl. Res 23 , 2012; 41–48.doi: 10.1111/j.1600‐0501.2011.02170.x 相似文献
99.
Henn S de Carvalho RV Ogliari FA de Souza AP Line SR da Silva AF Demarco FF Etges A Piva E 《Clinical oral investigations》2012,16(2):531-536
This study evaluated the effect of zinc methacrylate (ZM) on the inhibition of matrix metalloproteinase 2 (MMP-2) and the
ultimate tensile strength (UTS) of an experimental polymer. Enzymes secreted from mouse gingival tissues were analyzed by
gelatin zymography in buffers containing 5 mM CaCl2 (Tris–CaCl2) in 50 mM Tris–HCl buffer with various concentrations of ZM (0.5, 1, 2, 4, 8, and 16 mM). The matrix metalloproteinases present
in the conditioned media were characterized by immunoprecipitation. The polymer UTS evaluation was performed in eight groups
with various concentrations of ZM (0, 0.5, 1, 2.5, 5, 10, 20, and 30 wt.%), in a mechanical testing machine. MMP-2 (62 kDa)
was detected in the zymographic assays and inhibited by ZM in all tested concentrations. UTS data were submitted to one-way
ANOVA and Tukey's test (α = 0.05), and no significant differences were observed among groups, except in the polymer containing 30% ZM, presenting a
significantly lower value when compared with the control group (p < 0.05). The results suggest that ZM inhibits MMP-2 expression in all concentrations tested, while small concentrations did
not affect the ultimate tensile strength of the polymer. Zinc methacrylate is a metalloproteinase inhibitor that can be copolymerized
with other methacrylate monomers. Yet, the addition of ZM did not affect the resin bond strength. Thus, in vivo tests should
be performed to evaluate the performance of this material. 相似文献
100.
Coelho-De-Souza FH Camargo JC Beskow T Balestrin MD Klein-Júnior CA Demarco FF 《Journal of applied oral science : revista FOB》2012,20(2):174-179