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Clinical Oral Investigations - The aim of this study was to evaluate the quality, readability, and popularity of patient-oriented online information about peri-implantitis. The term...  相似文献   
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Employing 2 different coarse-grained models, we evaluated the effect of intramolecular domain-domain distances and hinge flexibility on the general solution structure of monoclonal antibodies (mAbs), within the context of protein-protein steric repulsion. These models explicitly account for the hinge region, and represent antibodies at either domain or subdomain levels (i.e., 4-bead and 7-bead representations, respectively). Additionally, different levels of mAb flexibility are also considered. When evaluating mAbs as rigid structures, analysis of small-angle scattering profiles showed that changes in the relative internal distances between Fc and Fab domains significantly alter the local arrangement of neighboring molecules, as well as the molecular packing of the concentrated mAb solutions. Likewise, enabling hinge flexibility in either of the mAb models led to qualitatively similar results, where flexibility increases the spatial molecular arrangement at elevated concentrations. This occurs because fluctuations in mAb quaternary structure are modulated by the close proximity between molecules at elevated concentrations (>50 mg mL?1), yielding an increased molecular packing and osmotic compressibility. However, our results also showed that the mechanism behind this synergy between flexibility and packing strongly depends on both the level of structural detail and the number of degrees-of-freedom considered in the coarse-grained model.  相似文献   
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The occurrence of a hepatoduodenal ligament teratoma is extremely rare,with only a few cases reported in the literature.This case report describes the discovery of a hepatoduodenal ligament lesion revealed during abdominal ultrasonography for cholelithiasis-related abdominal pain in a 27-year-old female.Cross-sectional imaging identified a 5 cm×4 cm heterogeneous mass of fat tissue with irregular calcification located in the posterior-superior aspect of the head of the pancreas.An encapsulated lesion showing no invasion to the common bile duct or adjacent organs and vessels was exposed during laparotomy and resected.Intraop-erative cholangiography during the cholecystectomy showed no abnormalities.The postoperative course was uneventful.Pathological analysis of the resected mass indicated hepatoduodenal ligament teratoma.This case report demonstrates that cross-sectional im-aging,such as computed tomography,can reveal sus-pected incidences of this rare type of teratoma,which can then be confirmed after pathologic analysis of the specimen.The prognosis after complete surgical resec-tion of lesions presenting with benign pathological fea-tures is excellent.  相似文献   
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The mechanisms by which neurons recognize the appropriate postsynaptic cells remain largely unknown. A useful approach to this problem is to use a system with a few identifiable neurons that form highly specific synaptic connections. We studied the development of synapses between two identified cercal sensory afferents and two giant interneurons (GIs) in the embryonic cockroach Periplaneta americana. By 46% of embryonic development, the axons of the filiform hair sensory neurons have entered the terminal ganglionic neuropil and grow alongside the GI primary dendrites, although they do not form synapses. From 50% of development, the GI dendrites grow outward from the center of the neuropil to contact the presynaptic axons and their branches. The sensory neurons begin to spike at 52% of development, and, from 55% of development, these action potentials evoked excitatory postsynaptic potentials in the GIs. Synaptic contacts were first seen at this time. The pattern of synaptic connections was highly specific from the outset. GI2 had strong input from the medial (M) afferent and had almost negligible input from the lateral (L) afferent, whereas GI3 had input from both. This specificity was present before bursts of spontaneous activity began in the sensory neurons at 59% of development. GI2 filopodia selectively formed synaptic contacts with the M axon rather than the L axon. The few contacts made by GI2 with the L axon had a normal morphology but fewer presynaptic densities. Filopodial insertions were not involved in selective synapse formation. In this system, highly specific synaptic recognition appears to be activity independent. © 1996 Wiley-Liss, Inc.  相似文献   
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We describe two infants suffering from severe pneumonia caused by respiratory syncytial virus (RSV) infection and needing mechanical ventilation with both high ventilator settings and a high fraction of inspired oxygen. The severity of the respiratory failure and the possibility of decreased and/or altered surfactant production led us to treat these infants with intratracheal instillation of natural surfactant. This resulted in an improvement of lung compliance and a decrease in the amount of oxygen required to maintain acceptable oxygen saturations. Intratracheal surfactant instillation might, therefore, be useful in the treatment of severe RSV pneumonia. Pediatr Pulmonol 1996; 22:412–415. © 1996 Wiley-Liss, Inc.  相似文献   
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Objective. To examine growth factor responses of human articular chondrocytes in aging and development. We have previously established a growth factor response profile for adult human articular chondrocytes and shown that transforming growth factor β (TGFβ) is the most potent mitogen among a variety of factors tested. Methods. Chondrocytes were isolated from human articular cartilage obtained from donors ages 11–83 years and tested in primary culture for proliferative responses to serum and recombinant preparations of the major chondrocyte growth factors. Proliferation was measured by 3H-thymidine incorporation and cell counting. Skeletal maturity of the young donors was determined by radiographic assessment of Risser's index. Results. Chondrocytes showed a continuous age-related decline in the proliferative response to serum. Analysis of recombinant growth factors showed that with increasing donor age, there was a decrease in the levels of DNA synthesis in response to all factors tested. In chondrocytes from adult donors, there was no change in the relative potencies of the different growth factors. The decrease in the levels of DNA synthesis as measured by 3H-thymidine incorporation corresponded to a reduced rate of in vitro cell replication with increasing donor age. In addition to the quantitative changes in the proliferative responses of chondrocytes with increasing age, there was a qualitative change in the pattern of growth factor responses during development. Cells from young donors (ages 10–20) responded better to platelet-derived growth factor, AA chain homodimer (PDGF-AA) than to TGFβ1, while the inverse pattern was seen in cells from adult donors. This decrease in the response to PDGF-AA was significantly correlated with increasing skeletal maturity. Conclusion. Chondrocyte growth factor responsiveness shows qualitative changes during development, and after skeletal maturity, there is a profound decline in the levels of DNA synthesis and cell replication in response to the known chondrocyte growth factors.  相似文献   
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